Biology - Cancer

Cancer Cells

Cancer cells have a number of abnormal characteristics that prevent them from functioning in the same manner as normal cells. They divide repeatedly and form tumors in the place of origin and in other parts of the body. Cancer is actually over a hundred different diseases. However, these characteristics are common to cancer cells.

Causes and Prevention of Cancer

Whether cancer develops is partially due to inherited genes, but exposure to carcinogens such as UV radiation, tobacco smoke, pollutants, industrial chemicals, and certain viruses play a significant role also.

Diagnosis of Cancer

Cancer is usually diagnosed by certain screening procedures and by imaging the body and tissues, utilizing various techniques.

Treatment of Cancer

Surgery involving bone marrow transplants followed by radiation and/or chemotherapy has now become fairly routine. Other methods are under investigation.

Characteristics of Cancer Cells

Cancer is a cellular disease. Cancer Cells Lack Differentiation Cancer cells are nonspecialized and do not contribute to the functioning of a body part. Cancer Cells Have Abnormal Nuclei The nuclei of cancer cells are enlarged and may contain an abnormal number of chromosomes. Cancer Cells Have Unlimited Potential to Replicate Cancer cells are immortal and keep on dividing for an unlimited number of times. Cancer Cells Form Tumors Cancer cells pile on top of one another and grow in multiple layers, forming a tumor. Cancer Cells Have No Need for Growth Factors (chemical signals) Cancer cells keep on dividing, even when stimulatory growth factors are absent, and they do not respond to inhibitory growth factors. Cancer Cells Gradually Become Abnormal The process of carcinogens is a multistage process that can be divided into three phases: initiation, promotion, and progression. Cancer Cells Undergo Angiogenesis and Metastasis Tumors require a well-developed capillary network to bring nutrients and oxygen. Angiogenesis is the formation of new blood vessels. When cancer cells begin new tumors far from the primary tumor, metastasis has occurred.

Cancer Results from Gene Mutation

Proto-oncogenes encode proteins that promote the cell cycle and prevent apoptosis. Tumor-suppressor genes encode proteins that inhibit the cell cycle and promote apoptosis.

Proto-Oncogenes Become Oncogenes

When proto-oncogenes mutate, they become cancer causing genes called oncogenes. These would be considered "gain of function" mutations. Some proto-oncogenes encode growth factors or growth factor receptors.

Tumor-Suppressor Genes Become Inactive

When tumor-suppressor genes mutate, their products no longer inhibit the cell cycle nor promote apoptosis. These mutations can be called "loss of function" mutations.

Types of Cancer

Oncology is the study of cancer. Tumors are classified according to their place of origin: carcinomas are cancers of epithelial cells, sarcomas are cancers that arise in muscles and connective tissue, leukemias are cancers of the blood, and lymphomas are tumors of lymphatic tissue. Common Cancers Cancer can occur in all parts of the body, but some organs, such as the lungs, the colon/rectum, the blood, breast, and skin are more susceptible than others.

Cancer is caused by a combination of heredity and environmental factors.

Heredity Certain cancers, such as breast, lung, and colon cancers, run in families. Some childhood cancers are inherited as a dominant gene. Environmental Carcinogens A mutagen is an agent that enhances the chance of a DNA mutation. A carcinogen is an environmental agent that can trigger cancer. Carcinogens are frequently mutagenic. Radiation Ultraviolet radiation in sunlight and tanning lamps triggers the development of skin cancers. Melanoma is the spreading form of skin cancer. Radon gas can lead to lung cancer. X rays and nuclear radiation can lead to cancer. Organic Chemicals Tobacco smoke contains numerous organic chemicals that can lead to cancers of the lung, mouth, larynx, bladder, kidney, and pancreas. Pollutants Exposure to pollutants such as metals, dust, chemicals, or pesticides can increase the risk of cancer. Viruses At least four types of DNA viruses, hepatitis B and C viruses, Epstein-Barr virus, and human papillomavirus, are directly believed to cause human cancers. Dietary Choices Nutrition is emerging as a way to help prevent cancer. The consumption of fruits and vegetables, whole grains instead of refined grains, and a limited consumption of red meats are recommended. Moderate exercise is also recommended.

The earlier a cancer is detected, the more likely it can be effectively treated.

Seven Warning Signs The seven warning signs of cancer spell the word CAUTION (change in bowel or bladder habits, a sore that does not heal, unusual bleeding or discharge, thickening or a lump in breast or elsewhere, indigestion or difficult in swallowing, obvious change in wart or mole, nagging cough or hoarseness.)

Routine Screening Tests

Pap smears for cervical cancer are an example of a routine screening test. For breast cancer, routine self-exam, exam by a doctor, and mammography are recommended. Colon cancer screening involves a digital rectal exam, sigmoidoscopy, a fecal occult blood test, and colonoscopy. Diagnosis of cancer in other parts of the body may involve other types of imaging. Tumor Marker Tests Blood tests for tumor antigens/antibodies produced against tumors are called tumor marker tests. They can be used to detect first-time cancer and cancer relapses. Genetic Tests When individuals test positive for the presence of marker genes, such as the BRCA1 breast cancer oncogene, they should be vigilant for signs of cancer. Microsatellite abnormalities and the presence of telomerase indicate that cancer is present.

Standard Therapies

Surgery Surgery is sufficient for cancer in situ. Surgery followed by radiation is recommended when cancer cells may have been left behind. Radiation Therapy Ionizing radiation causes chromosomal breakage and cell cycle disruption. Therefore, dividing cells, such as cancer cells, are more susceptible to its effects than other cells. Chemotherapy Chemotherapy is used for metastatic cancers that may have spread throughout the body. Chemotherapeutic drugs kill cells during cell division. Certain types of cancers are now successfully treated by combination chemotherapy alone. Bone marrow transplants are used when a patient is to receive high doses of radiation or chemotherapy.

Newer Therapies

Immunotherapy The use of monoclonal antibodies designed to combine with receptors on cancer cells is under investigation. A cancer vaccine that stimulates the body's immune system to attack cancer cells has promise but has yet to be highly effective. p53 Gene Therapy Adenoviruses are used to carry a normal copy of the p53 gene into cancerous tissues. Other Therapies Other therapies such as the use of antiangiogenic drugs are being investigated.

Characteristics

Lack differentiation and do not contribute to body functioning Have abnormal nuclei that are enlarged and may have an abnormal number of chromosomes Unlimited ability to divide one way is through turning on the telomerase gene that allows telomeres on chromosomes to continually be built thus allowing a cell to divide over and over again Form tumors Benign tumors are usually encapsulated and do not invade adjacent tissue while a cancerous tumor usually is not encapsulated and eventually invades surrounding tissue Can divide without growth factors Become abnormal gradually through a multistage process Undergo angiogenesis and metastasis

The 3 phases in the development of cancer cells

Initiation - a single cell undergoes a mutation that causes it to divide repeatedly Promotion - a tumor develops and cells within the tumor mutate Progression - a cell mutates in such a way that allows it to invade surrounding tissue

More characteristics

a. Cell (dark pink): acquires a mutation for repeated cell division. b. New mutations arise, and one cell (brown) has the ability to start a tumor. Cancer in situ. The tumor is at its place of origin. One cell (purple) mutates further. c. Cells have gained the ability to invade underlying tissues by producing a proteinase enzyme. d. Cancer cells now have the ability to invade lymphatic and blood vessels. e. New metastatic tumors are found some distance from the original tumor.

Angiogenesis

Angiogenesis: formation of new blood vessels to supply nutrients and oxygen to the tumor

Metastasis

Metastasis: cells move into the bloodstream or lymphatic vessels to make new tumors at distant sites from the primary tumor

Proto-oncogenes

products promote the cell cycle and prevent cell death (apoptosis

Tumor-suppressor genes

products inhibit the cell cycle and promote apoptosis

Mutations in the genes above can cause cancer, in fact proto-oncogenes that have mutated are cancer-causing genes called

oncogenes

Oncology

study of cancer

Carcinomas

Carcinomas: cancers of the epithelial tissue

Adenocarcinomas

Adenocarcinomas: cancers of glandular epithelial cells

Sarcomas

Sarcomas: cancers of muscle and connective tissues

Leukemias

Leukemias: cancers of the blood

Lymphoma

Lymphoma: cancers of lymphatic tissues

Causes of cancer

Genetics Environmental carcinogens Radiation Environmental carcinogens (tobacco smoke and pollutants) Viruses

Genetic causes of cancer

Examples of genes associated with cancer: BRCA1 and BRCA2 - tumor-suppressor genes that are associated with breast cancer RB - a tumor-suppressor gene that is associated with an eye tumor RET - proto-oncogene that is associated with thyroid cancer

mutations

Mutations of these genes predispose individuals to certain cancers but it takes at least one more acquired mutation during their lifetime to develop cancer

Environmental causes of cancer

Radiation: Environmental factors such as UV light (in sunlight or tanning lights) and x-rays can cause mutation in DNA Organic chemicals: Tobacco smoke: increases cancer of lungs, mouth, larynx and others Pollutants: substances such as metals, dust, chemicals and pesticides increase the risk of cancer Viruses: Hepatitis B & C: virus that can cause liver cancer Epstein-Barr virus: can cause Burkitt's lymphoma Human papillomavirus: can cause cervical cancer

Protective Behaviors

Don't use tobacco Don't sunbathe or use a tanning booth Avoid radiation Be tested for cancer Be aware of occupational hazards Be aware of postmenopausal hormone therapy Get vaccinated

The Right Diet

Avoid obesity Eat plenty of high-fiber foods Increase consumption of foods that are rich in vitamins A and C Reduce consumption of salt-cured, smoked, or nitrite-cured foods Include vegetables from the cabbage family in the diet Drink alcohol in moderation

Seven signs

Change in bowel or bladder habits A sore that does not heal Unusual bleeding or discharge Thickening or lump in breast or elsewhere Indigestion or difficulty in swallowing Obvious change in wart or mole Nagging cough or hoarseness CAUTION

Some routine screening tests for cancer

Self-examination - monthly exams of breasts and testicles starting at age 20 Colonoscopy - every 5 years starting at age 50 Mammogram - yearly after age 40 Pap smear - should begin these 3 years after vaginal intercourse or no later than age 21

Detecting melanoma skin cancer

A - asymmetry B - border is irregular C - color varies from one area to another D - diameter is larger than 6mm

A = Asymmetry,

A = Asymmetry, one half the mole does not look like the other half.

B = Border

B = Border, irregular scalloped or poorly circumscribed border.

C = Color

C = Color, varied from one area to another; shades of tan, brown, black, or sometimes white, red, or blue.

D = Diameter

D = Diameter, larger than 6 mm (the diameter of a pencil eraser).

E = Elevated

E = Elevated above skin surface, and Evolving, or changing over time

Other ways to detect cancer

Tumor marker tests - blood tests for tumor antigens/antibodies CEA (carcinoembryonic antigen) antigen can be detected in someone with colon cancer PSA (prostate-specific antigen) test for prostate cancer Genetic tests - tests for mutations in proto-oncogenes and tumor-suppressor genes RET gene (thyroid cancer) P16 gene (associated with melanoma) BRCA1 (breast cancer) A diagnosis of cancer can be confirmed by performing a biopsy

Standard cancer treatments

Surgery - removal of small cancers Radiation therapy - localized therapy that causes chromosomal breakage and disrupts the cell cycle Chemotherapy - drugs that treat the whole body that kills cells by damaging their DNA or interfering with DNA synthesis Bone marrow transplants - transplant bone marrow from one individual to another

Newer cancer therapies

Immunotherapy - inject immune cells that are genetically engineered to bear the tumor's antigens Passive immunotherapy - antibodies that are linked to radioactive isotopes or chemotherapeutic drugs are injected into the body p53 gene therapy - a retrovirus in clinical trial that is injected into the body where it will infect and kill only tumor cells (cells that lack p53 = tumor cells) Angiogenesis inhibition - Angiostatin and endostatin are drugs in clinical trials that appear to inhibit angiogenesis

Immunotherapy

1. Antigen-presenting cells (APCs) are removed from the patient. 2. APCs are genetically engineered to have genes for tumor antigens. 3. APCs display tumor antigens at their surface. 4. Genetically engineered cells are returned to patient. 5. APCs present tumor antigen to cytotoxic T cells, and they attack tumor cells.

A ______ gene codes for a repressor protein.
A) promoter
B) operator
C) structural
D) regulator
E) transcription

d) regulator A regulator gene codes for a repressor protein.

The promoter is ___________.
A) a short sequence of DNA where the repressor binds, preventing RNA polymerase from attaching to the promoter
B) a short sequence of DNA where RNA polymerase first attaches when a gene is to be transcribed
C) one to several genes of a metabolic pathway that are transcribed as a unit
D) a gene that codes for a repressor protein
E) any dominant gene

D) a gene that codes for a repressor protein The promoter is a short sequence of DNA where RNA polymerase first attaches when a gene is to be transcribed.

Each cell contains a full complement of genes but only certain genes are active at any one time.
A) True
B) False

true

A regulator gene located inside the operon codes for a promoter protein that can bind to the operator and switch on the operon.
A) True
B) False

false

The operon model explains a means of transcriptional control in bacteria.
A) True
B) False

true

Which of the following is NOT true concerning control of gene expression in eukaryotic cells?
A) Transcriptional control is the most important factor.
B) Transcription factors help RNA polymerase bind to a promoter.
C) Transcription activators binding to enhancers can speed up transcription.
D) Part of transcriptional control includes the processing of mRNA before it leaves the nucleus.
E) All of the above are correct.

D) Part of transcriptional control includes the processing of mRNA before it leaves the nucleus. The processing of mRNA before it leaves the nucleus occurs after transcription has taken place.

All mRNA molecules exist for the same amount of time within a cell.
A) True
B) False

false

Which of the following is NOT true regarding protein activity?
A) All proteins are active immediately after being formed.
B) Proteasomes are protein complexes responsible for degrading proteins.
C) Proteins will fold into a three dimensional structure after being synthesized.
D) Some amino acids may need to be removed before a protein becomes functional.
E) Protein activity is usually controlled by feedback control.

A) All proteins are active immediately after being formed.

Ordinarily, cells with damaged DNA undergo ______ or programmed cell death.
A) apoptosis
B) tumor-suppression
C) differentiation
D) angiogenesis
E) metastasis

A) apoptosis

Cancer cells exhibit uncontrolled and disorganized growth.
A) True
B) False

true

Formation of new blood vessels is required to bring nutrients and oxygen to cancerous tumors.
A) True
B) False

true

Cancer cells cannot enter the cell cycle and therefore are mortal.
A) True
B) False

false cancer cells enter the cell cycle repeatedly, and in this way they are immortal.

______ are cancer-causing genes.
A) Metastases
B) Mutagens
C) Carcinogens
D) Oncogenes
E) Homozygous recessive genes

D) Oncogenes Oncogenes are cancer-causing genes. Metastases are clusters of cancerous cells that have broken away and settled elsewhere.

A cell contains many ___________ where one mutation can cause them to become oncogenes.
A) metastases
B) tumor-suppressor
C) benign tumors
D) proto-oncogenes
E) carcinogens

D) proto-oncogenes A cell contains many proto-oncogenes where one mutation can cause them to become oncogenes. Metastases are clusters of cancerous cells that have broken away and settled elsewhere.

Proto-oncogenes promote the cell cycle and _____ genes inhibit the cell cycle.
A) recessive
B) tumor-suppressor
C) benign
D) proto-oncogenes
E) carcinogens

B) tumor-suppressor Proto-oncogenes promote the cell cycle and tumor-suppressor genes inhibit the cell cycle.

Which of these characteristics is typical of cancer cell?
A) Cancer cells lack contact inhibition.
B) Cancer cells induce angiogenesis.
C) Cancer cells lack specialization.
D) Cancer cells can metastasize.
E) All of these are correct

E) All of these are correct Cancer cells lack contact inhibition, induce angiogenesis, lack specialization, and can metastasize.

A ________ is an environmental agent that can contribute to the development of cancer.
A) mutagen
B) fibrinogen
C) carcinogen
D) factor

A) mutagen A carcinogen is an environmental agent that can contribute to the development of cancer.

some examples of carcinogens are _________.
A) certain organic chemicals
B) radiation
C) viruses
D) All of these are correct

D) All of these are correct

Which DNA virus has been linked to a type of human cancer?
A) hepatitis B virus
B) human papillomavirus
C) Epstein-Barr virus
D) All of the above.

D) All of the above.

The pap smear is a test for ________ cancer.
A) colon
B) cervical
C) breast
D) ovarian
E) liver

B) cervical

The standard methods of treatment for cancer are _________.
A) surgery
B) radiation
C) chemotherapy
D) All of the above

D) All of the above Surgery, radiation, and chemotherapy are the standard methods of cancer therapy.

most chemotherapy drugs kill cells by damaging ___________.
A) DNA
B) protein
C) nearby blood vessels
D) the cell membrane
E) All of the above

A) DNA Most chemotherapy drugs kill cells by damaging their DNA or interfering with DNA synthesis.

angiogenesis

Formation of new blood vessels; one mechanism by which cancer spreads

apoptosis

Programmed cell death involving a cascade of specific cellular events leading to death and destruction of the cell.

carcinogen

Environmental agent that causes mutations leading to the development of cancer.

chemotherapy

way to catch cancer cells that have spread throughout the body; kills cells by damaging their DNA or interfering with DNA synthesis.

enhancer

Elements that regulate transcription from nearby genes. Function by acting as binding sites for transcription factors.

genetic test

Test that looks for genetic mutations in proto-oncogenes and tumor-suppressor genes; makes it possible to detect the likelihood of cancer.

growth factor

Chemical signal that regulates mitosis and differentiation of cells that have receptors for it; important in such processes as fetal development, tissue maintenance and repair, and hematopoiesis; sometimes a contributing factor in cancer.

leukemia

Cancer of the blood-forming tissues leading to the overproduction of abnormal white blood cells.

lymphoma

Cancer of lymphatic tissue. 5

metastasis

Formation of new tumors distant from the primary tumor.

oncogene

Cancer-causing gene.

operon

Cluster of bacterial genes along with the DNA sequences that control their transcription.

proto-oncogene

Encodes for proteins that promote the cell cycle and prevent apoptosis.

regulatory gene

An an operon, a gene that codes for a protein that regulates the expression of other genes.

repressor

In an operon, protein molecule that binds to an operator, preventing transcription of structural genes.

reproductive cloning

Fenetically identical to the original individual.

signal transduction pathway

Activation and inhibition of intracellular targets after binding of growth factors.

telomere

Sequence of bases at the end of chromosomes that keeps them from fusing with one another.

therapeutic cloning

Used to create mature cells of various cell types. Also, used to learn about specialization of cells and provide cells and tissue to treat human illnesses

transcription activator

Protein that speeds transcription.

transcription factor

Protein that initiates transcription by RNA polymerase and thereby starts the process that results in gene expression.

tumor marker test

Blood test for tumor antigens/antibodies.

tumor-suppressor gene

Gene that codes for a protein that ordinarily suppresses cell division; inactivity can lead to a tumor.

Sigmoidoscopy is a test for _______ cancer.

colon

Mutated tumor-suppressor genes cause _____.

d. Both a and b are correct.

Which of the following is a correct sign of possible malignant melanoma?

irregular border of a mole

_______ involves genetically engineered antigen-presenting cells that give tumor antigens to cytotoxic T-cells that kill the tumor cells.

Immunotherapy

Most chemotherapeutic drugs kill cells by damaging _______.

DNA

______ is an X-ray study of the breast used to detect tumors too small to be felt.

mammography

An agent that causes mutation is a/an:

mutagen

Which of the following is NOT a warning signal of possible cancer?

cold like symptoms

Which step in carcinogenesis is correctly matched with its description?

Initiation - a single cell has a mutation that allows it to divide repeatedly.

A _______ is an environmental agent that can contribute to the development of cancer.

carcinogen

Which cancer classification is NOT matched with its description?

sarcomas - cancer of the liver

What is the correct order of steps in carcinogenesis?

initiation, promotion, progression

The formation of new blood vessels is _________.

angiogenesis.

What DNA virus has been linked to a type of human cancer?

All of these are correct.

In cancer cells, oncogenes cause:

both A and B Oncogenes can cause both an excess of Cyclin D and an excess of p53 inhibitors

The most common cancer in males is:

prostate

What percent of all cancers are thought to be related to the usage of tobacco products?

80

___ is the study of cancer.

oncology

the most common cancer in females is:

breast

Cancer in situ _______.

is found in one place

Which of these characteristics is typical of cancer cells?

all

Cancer cells produce _____ enzymes that degrade membranes which allows movement into other tissues.

proteinase

The standard methods of treatment for cancer are _______.

All of these are correct.

Proto-oncogenes encode for proteins that _____.

Both a and b are correct. Answer Feedback: Proto-oncogenes encode for proteins that promote the cell cycle and prevent apoptosis

Which type of cancer causes the most deaths in both males and females?

lung

A(n) ______ is a cancer-causing gene.

oncogene

Oncogenes frequently involved in human cancers belong to the ______ gene family.

ras

Which of the following is NOT an environmental carcinogen?

high fiber food Answer Feedback: Examples of carcinogens include certain organic chemicals, radiation, and viruses

The PAP test is used to test for _____ cancer.

cervical

Tumors that fail to have cells undergoing apoptosis lack an active _________ gene.

p53

Identify the characteristics that are typical of cancer cells?
A) cancer cells lack contact inhibition
B) cancer cells induce angiogenesis
C) cancer cells lack differentiation
D) All of these are correct.

D

What is the function of telomerase?
A) rebuild telomere sequences
B) destroy telomere sequences
C) connect different telomere sequences
D) separate different telomere sequences

A) rebuild telomere sequences

A normal cells typically divides 60 to 70 times before it dies while cancer cells:
A) divide an unlimited number of times
B) divide twice that amount
C) may divide 60-70 times
D) are unable to divide

A) divide an unlimited number of times

When cancer cells undergo metastasis
A) tumors release growth factors.
B) tumors increase in size.
C) tumors have nondifferentiated cells.
D) cancer spreads throughout the body.

D) cancer spreads throughout the body.

Which of the following proteins acts as a transcription factor involved in turning on the expression of genes whose products are cell cycle inhibitors?
A) p14
B) p53
C) p76
D) p22

B) p53

Which of the following is not considered part of the process by which cancer cells gradually become abnormal?
A) Initiation
B) Promotion
C) Transcription
D) Progression

C) Transcription

A/an ________ tumor is usually encapsulated and noninvasive.
A) benign tumor
B) malignant tumor
C) neoplasm
D) proteolytic

A) benign tumor

The ________ predisposes an individual to thyroid cancer.
A) HOM
B) HOX
C) RB
D) RET

C) RET

___ is a type of skin cancer which tends to metastasize and can be fatal.
A) Basal cell carcinoma
B) Lymphoma
C) Sarcoma
D) Melanoma

D) Melanoma

Choose the following that is not associated with the American Cancer Society's caution warning signals.
A) thickening or lump in breast
B) indigestion or difficulty swallowing
C) obvious change in wart or mole
D) All of the choices are associated.

D

The PSA test is used to detect _____________.
A) colon cancer
B) liver cancer
C) prostate cancer
D) breast cancer

C) Prostate

Which of the following has been proposed as future cancer therapy?
A) monoclonal antibodies
B) p53 gene therapy/induced tumor apoptosis
C) angiogenesis inhibition
D) All of the choices are correct.

D All

Cancer cells have no need for growth factors

chemical signals between cells tell them whether or not they should be dividing. These chemical cells called growth factors are of two types: stimulator growth factors and inhibitory growth factors. Cancer cells keep dividing, even when stimulatory growth factors are absent and they do not respond to inhibitory growth factors

what are the four leading types of cancer in men and women?

Men: prostate, lung and bronchus, colon and rectum, urinary bladder Women: breast, colon and rectum, uterine corpus, non-hodgkin lymphoma

proto oncogenes become oncogenes

when proto oncogenes mutate, they become cancer causing genes called oncognes. Whatever a proto oncogene does an oncogene does better

whereas _____________ stimulates the cell cycle, ____________________ inhibit cell cycles

proto oncogenes, tumor suppressor genes

Growth factors lead to

increased cell division, the functioning of cyclin proteins, progression through the cell cycle

which of the following is not true of the gene p53

normally p53 functions to stop the cell cycle and initiate repair enzyes when necessary

which association is not correct?

mutated tumor suppressor genes - code for cyclin and proteins that inhibit the activity of p53

following each cell cycle, telomers

get shorter

cyclin

a protein molecule that hsas to be present for a cell to proceed from interphase to mitosis. When cancer develops, the cell cycle occurs repeatedly due to mutations in proto oncogenes and tumor suppressor genes

differentiation

the process of cellular development by which a cell acquires a specific structure and function. Cancer cells do not contribute to the functioning of the body like, for example, red cells that are differentiated cells in the circulatory system

nuclei of cancer cells

enlarged, contain abnormal number of chromosomes - the nuclei takes up most of the cell. The chromosomes are defective. Some chromosomes may be duplicated or deleted. Gene amplification are extra copies of specific genes. Usually damaged DNA cells undergo apoptosis, or programmed cell death. Cancer cells do not even though they are abnormal.

telomere proteins

chromosomes end with special repetitive DNA sequences called telomeres. Specific proteins bind in both normal and cancerous cells. They protect the ends of chromosomes from DNA repair enzymes. Enzymes effectively repair DNA in the center of the chromosome, they tend to bind together at the naked ends of chromosomes. In normal cells the telomeres get shorter after each cycle. Repair enzymes cause chromosome ends to bind together and apoptosis occurs causing the cell to die. Telomere is an enzyme. The gene that codes for telomere is constantly turned on in cancer and they constantly rebuild. The telomeres remain at constant length and keep dividing over and over.

tissues that divide frequently are more likely to become cancerous in the

respiratory and digestive tracts

initiation

a single cell undergoes a mutation that causes it to begin to divide repeatedly

promotion

a tumor develops and the tumor cells continue to mutate and divide

progression

one cell undergoes a mutation that gives it selective advantage over the other cells. The process is repeated until a cell has the ability to invade surrounding areas

angiogenesis and metastasis

angiogenesis the formation of new blood vessels - low oxygen content in the middle of a tumor turns on gene coding for angiogenic growth factors that diffuse into nearby tissues causing new vessels to form. To metastasize cancer cells make make their way across the basement membrane and invade a blood or lymphatic vessel - invasive cancer cells are sperm shaped and don't look normal.

Cancer cells produce proteinase enzymes

that degrade the basement membrane and allow them to invade underlying tissue. Not many cancer cells achieve metastasis, only 1 in 10,0000 - lowers prognosis

cyclin is a protein molecule that has to be present for a cell to proceed from interphase to mitosis

when cancer develops the cell cycle occurs repeatedly

proto oncogenes are proteins that inhibit the cell cycle and preent apopotosis

like the gas pedal on a car because they cause acceleration of the cell cycle

tumor suppressor genes code for proteins that inhibit the cell cycle and promote apopotosis

they are like the brakes on a car because they inhibit acceleration

several proto oncongenes code for Ras proteins that promote mitosis by activating cyclin

ras oncongenes are typically found in many different types of cancer. Cyclin D is a proto oncogene that codes for cyclin directly. When this gene becomes oncogne cyclin is readily available all the time

p53 is a protein that activates repair enzymes

p53 turns on genes that stop teh cell cycle from proceeding. If repair is impossible the p53 protein promotes apoptosis - programmed cell death. When the proto oncogene becomes an oncogene no p53 will be available regardless of how much is made. Many turos are lacing in p53 activity

Bax

promotes apoptosis. When Bax mutates, Bax protein is not present and apoptosis is less likely to occur. The bax gene contains a line of eight consecutive G bases in its DNA. When the same base molecules are lined up in this fashion the gene is more likely to be subject to mutation

1 in 3 americans will deal with cancer in their lifetime

carcinomas are cancers of the epithelial tissue - tumors are classified by their point of origin. Adenocarcinomas are cancers of glandular epitheilial cells. Carcinomas include skin, breast, liver, pancreas, intestines, lung, prostate and thyroid. Sarcomas are muscle and connective tissue. Leukemias are cancer of the blood. Lymphomas are cancers of lymphatic tissue. Blastoma is cancer composed of immature cells.

Transposons

small, mobile sequences of DNA that have the ability to move throughout the genome. They are closely related to retroviruses. Also known as jumping genes. our genome has over 3.4 billion nucleotides. There have been cases where a transposon has caused a loss of cell cycle control ad can be factor in development of cancer and other diseases such as hemophilia ad muscular dystrophy

radiation is localized therapy

ionizing radiation causes chromosomal breakage and cell cycle disruption. Cancer of the cervix, larynx and early stages of prostate & hodgkins disease are treated with radiation alone. Xrays and gamma rays are the mainstays of radiation therapy but protons and neutrons also work well. Proton beams can be aimed like a rifle. Side effects are weakness and fatique, dry mouth, nauseau, diarrhea affect digestive tract. Dry, red or irritated skin or burns, hair loss at the treatment site can be permanent, side effects usually temporary

chemotherapy used for cancer cells that have spread

treats entire body. Kills cells by damaging DNA or interfering with DNA synthesis.

alkylating agents

interfere with the growth of cancer cells by blocking the replication of DNA

antimetabolites

block enzymes needed by cancer cells to live and grow

antitumor antibiotics

different from those used to treat bacterial infections - interfere with DNA, blocking certain enzymes and cell division and changing cell membranes

mitotic inhibitors

inhibit cell division or hinder certain enzymes necessary in cell reproduction process

nitrosoureas

medications that impede the enzymes that help repair DNA

chemo is specifically designed for the particular cancer

in some cancers a small portion of chromosome 9 is missing, therefore, DNA metabolism differs in the cancerous cells compared with normal cells. Specific chemo for the cancer can exploit this metabolic difference and destroy the cancer cells

taxol

extracted from bark of the pacific yew tree is effective against ovarian, breast, head and neck tumors. It interferes with microtubules needed for cell division. Taxoids were developed by chemists may be more powerful and have fewer side effects than taxol

survival rate for leukemia

in children is 80%

hodgkins

used to kill 2 out of 3 patients, new medication combinations can wipe out the disease in a matter of months. 3 out of 4 patients achieve a cure

multidrug resistance

chemo can fail because cancer cells become resistant to one or several chemo meds because a plasma membrane carrier pumps the drug out of the cancer cell before it can be harmed.

bone marrow transplants

sometimes done along with chemo. Red bone marrow contains large populations of dividing cells. Red bone marrow is prone to destruction by chemo drugs. In bone marrow transplantation a patients stem cells are harvested and stored before chemo begins. high doses of radiation or chemo drugs are given in a relatively short time. This prevents multidrug resistance from occurring. Stored stem cells are returned to the patient by injection, they make they way to the bony cavities and resume blood cell formation

melacine

a vaccine contains broken melanoma cells from two differnt sources is under investigation for use against melanoma. another idea is to use immune cells genetically engineered to bear the tumor's antigens.When returned to the body they produce cytokines. Cytokines stimulate the body to attack tumors. Altered immune cells present the tumor antigen to cytotoxic T cells when then go forth and destroy tumor cells in the body.

Passive immunotherapy

monoclonal antibodies have the same structure because they are produced by the same plasma cells. some monoclonal antibodies are designed to zero in on the receptor proteins of cancer cells. To increase the killing power of monoclonal antibodies they are linked to radioactive isotopes or chemotherapeutic drugs

gene therapy

p53 gene expression is neeed for only 19 hours to trigger apoptosis, programmed cell death. the p53 gene seems to trigger cell death only in cancer cells. elevating p53 levels in normal cells doesn't do any harm, because apoptosis requires extensive DNA damage

adenoviruses

when adenoviruses infect a cell they produce a protein that inactivates p53. In a cleverly designed procedure, investigators genetically engineered an adenovirus that lacks the gene for this protein. Now the adenovirus can infect and kill only cells that lack a p53 gene - tumor cells. Injected adenovirus spreads through the cancer killing tumor cells as it goes - clinical trials have begun

Antiangiogenic drugs

confine tumors by breaking up the network of new capillaries in the vicinity of the tumor. Two drugs called angiostatin and endostatin inhibit angiogenesis in laboratory animals

cancer cells tend to be motile

they have a disorganized internal cytoskeleton and lack intact actin filament bundles.

to grow larger than about a billion cells (about the size of a pea)

a tumor must have a well developed capillary network to bring it nutrients and oxygen - angiogenesis is the formation of new blood vessels.

to lesson side effects of chemo

nausea, vomiting, diarrhea, weight loss, hair loss, anxiety, depression, extreme fatigue. Antiemetic drugs alleviate nausea and vomiting. Genetically engineered erythropoietin helps stimulate red blood cell production to reduce fatigue. Marinol (like marijuana) stimulates appetite and helps with weight loss. Hair loss can be minimized by cryotherapy - applying cold packs on the scalp during treatment. Cold slow the metabolic rate of hair follicles so more follicles survive the treatment. Antidepressants and anti anxiety medications for depression. Yoga, meditation and tai chi help to relax. Hypnosis can be tried. Aromatherapy, massage and music ease tension and stress by stimulating pleasure centers in the brain. Exercise produces endorphins, the brain's pain relieving neurotransmitters

leukemia, lymphomas and testicular cancer

are successfully treated with chemo alone

routine screen testing

self examination followed by physician exam (ABCDE) pap test for cervical cancer - examine cells under microscope for abnormalities colon cancer - digital rectal exam, flexible ssigmoidoscopy with a thin, pliable, lighted tube, stool blood test, colonoscopy - polyps are destroyed by lasers blood tests detect leukemia urinalysis diagnosis bladder cancer breast - mamography Computerize axial tomography (CAT scan) to locate size and location of tumors MRI useful for analyzing tumors in tissues surrounded by bone, brain or spinal cord radioactive scan after a radioactive isotope is administered can reveal abnormal isotope accumulation due to a tumor ultrasound confirm tumors of stomach, prostate, pancreas, kidney, uterus and ovary biopsy laparoscopy - permits viewing of body parts

tumor marker tests

blood tests for antigens and/or antibodies. Tumors release substances that provoke antibody response - if a patient has colon cancer, it is possible to use the presence of an antigen called carcinoembryonic antigen (CEA) to detect relapses. When CEA levels rise, tumor growth has occurred Tumor marker tests can be used for early cancer diagnosis Prostate specific antigen - PSA CA-125 test for ovarian cancer Alpha fetoprotein (AFP) test for liver tumors

Genetic tests

tests are available that signal the liklihood of cancer. Tests are available for colon, bladder, breast, thyroid and melanoma. A mutated RET gene means that thyroid cancer is present or may appear in the future. Mutated p16 gene is associated with melanoma. Breast cancer gene 1 = presence of BRCA1 Microsatellites are small regions of DNA that always have two (di-), three (tri-) or four (tetra-) nucleotide repeats. They compare the number of nucleotide DNA repeats in a lymphocyte microsateelite with the number ina microsatelite of a cell found in urine - the number of repeats is less in the cell from urine, a bladder tumor is suspected

telomerase

the enzyme that keeps telomeres a constant length in cells. The gene that codes for telomerase is turned off in normal cells but is active in cancer cells, if the test for the presence of telomerase is positive the cell is cancerous

Why is it important to catch cancer growths so soon?
A.
To interrupt initiation.
B.
To stop benign cells turning to malignant cells.
C.
To interrupt promotion of altered cells.
D.
To increase the metasis profile.

C. To interrupt promotion of altered cells.

Which are sites of Metastasis?
A.
Lungs
B.
Brain
C.
Bone
D.
Liver
E.
All the above.

All the above.

More abnormal, moderately differentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade II

Tom's growth has come back. The lab report shows that the growth is encapsulated and partially differentiated. There is no metasis and is rather large. What type of growth does Tom most likely have?
A.
Benign
B.
Malignant

Benign

Naturally occurring in protein used to prevent cancer cells from proliferating; interferes with the ability of cancer cells to replicate.
A.
Interferons
B.
Interleukins
C.
Attached radioactive substances

Interferons

Mindy has had radiation for a tumor on her tibia. What can she expect?
A.
Nausea
B.
Diarrhea
C.
Myelosuppression
D.
Cystitis

Myelosuppression

The maximum time a nurse should be in a room of a pt with internal radiation is:
A.
30 min/shift
B.
1 hr/shift
C.
30 min/4 hrs
D.
no time limit if shielding is in place

30 min/shift

What is the cause of generalized weakness and anorexia after being treated with radiation?
A.
Destruction of normal cells
B.
Waste products of cell destruction.
C.
Toxins released from cancer cells trying to survive.
D.
Natural effects of radiation exposure.

Waste products of cell destruction.

When a pt is given unsealed sources of radiation, what principles should be followed?
A.
Distance
B.
Shielding
C.
Time
D.
All the above

all

Mindy is a 5 year old girl with cancer. What is the best way to talk to her about her treatment?
A.
With objects or drawings to illustrate.
B.
Conversation about what is happening as she can handle concepts.
C.
Discussing peer status and body imagine is important.

With objects or drawings to illustrate.

Cancer cells do not have the ability to develop new blood vessels and don't need oxygen but needs nutrients to survive.
A.
True
B.
False

false

When should a pt be given Zofran?
A.
30 minutes before a meals and at bedtime
B.
30 minutes after meals and at bedtime
C.
30 minutes before chemortherapeutic agents.
D.
30 minutes after giving chemotherapeutic agents.

30 minutes after giving chemotherapeutic agents.

Cancer cells can easily survive in the blood and attach to body cavities.
A. True(Your Answer)
B. False(Missed)
Explanation
The turbulent blood flow must be survived by the cancer cell.

false

The pt understands cancer cells when the pt states:
A. Cancer cells uncontrollably dived.(Missed)
B. Cancer is a death sentence.
C. Mature cells function until they die.
D. Cancer cells are more cohesive than normal cells.

Cancer cells uncontrollably dived

Mucositis is:
A.
very painful
B.
ulceration of the tongue, mouth, esophogeal, GI tract
C.
disruption of bone tissue
D.
A&B
E.
All the above

A&B

Slightly different from normal cells, well differentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade I

Solid tumors from muscle, bone, fat and other connective tissue
A.
Carcinoma
B.
Sarcoma
C.
Lymphoma
D.
Leukemia

Sarcoma

Mary is on chemotherapy. Her labs come back with a WBC of 2000 and her neutrophils are 20%. She has a fever of 100.6. Is this a medical emergency?
A.
Yes
B.
No

yes

Solid tumors from epithelial tissue
A.
Carcinoma
B.
Sarcoma
C.
Lymphoma
D.
Leukemia

Carcinoma

Matt has had radiation therapy for a tumor in his neck. What can Matt expect?
A.
Change in taste
B.
Increased saliva production
C.
Hair Loss
D.
Dyspnea

hair loss

In order for metastasis to take place, cells must stop and adhere at a secondary to proliferate.
A.
True
B.
False

true

Very abnormal, poorly differentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade III

The nurse understands the side effects of Zofran when the nurse states:
A.
Insomnia
B.
Constipation/Diarrhea
C.
Restlessness
D.
Must be assessed for extrapyramidial effects

Constipation/Diarrhea

side effects of Reglan

B. Drowsiness

Primitive and undifferentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade IV

Carry's lab report came back with a poorly differentiated growth that is encapsulated. There is a marked increase in vascularity and is infiltrating. What type of growth is this most likely?
A.
Benign
B.
Malignant

malignant

TNM Classification System refers to:
A.
Tumor (primary)
B.
Lymph Node involvement
C.
Metastasis
D.
All the above.

all

Nick has had radiation treatment for a tumor in his lung. What can Nick expect?
A.
Asthma
B.
Bronchitits
C.
Dyspnea
D.
Pneumonitis

Dyspnea

Lori is talking with her nurse about factors that promote cancer. Lori weighs 245 lbs and eats a lot of fast food. She is on large doses of estrogen for another condition and is 45 years old. Lori understands her risks when she states:
A.
My diet and weight predispose me to cancer.
B.
My parents didn't have cancer so I won't have it.
C.
Self examination is important for finding and changes.
D.
It's too late to make lifestyle changes because of my age, the damage is done.

My diet and weight predispose me to cancer.

Which is the most common route of metastasis?
A.
Blood
B.
Lymph System
C.
Surgery
D.
Trauma to a tumor

lymph

Chemotherapy usually kills 100% of a tumor.
A.
True
B.
False

false

Increased growth of tumor including invasion and metasis is called:
A.
Initiation
B.
Promotion
C.
Progression

progression

The nurse understands Decadron when the nurse states:
A.
Can cause euphoria
B.
Can cause insomnia
C.
Can cause mild fluid retention
D.
Monitor electrolytes and glucose
E.
All the above.

all

Colony Stimulating Factors (CSF) do what?
A.
Stimulates blood cell production by the bone marrow
B.
Stimulates NK cell production
C.
Stimulates T4 cell production
D.
Stimulates non proliferation agents in cancer cells.

Stimulates blood cell production by the bone marrow

The lab report comes back on the pt showing a non encapsulated growth that is poorly differentiated. The growth also shows that they are unlike the parent cell. What type of growth is this most likely?
A.
Benign
B.
Malignant

malignant

Naturally occuring but not at therapeutic levels. Enhances natural killer cell activity.
A.
Interferons
B.
Interleukin
C.
Attached radioactive substances

Interleukin

What does it mean to treat a disease partially and insofar as possible, but not cure it completely?
A. Control
B. Palliation(Your Answer)
C. Stay
D. Long Term Viability

. Palliation(Your Answer)

Radiation therapy is used to treat a tumor before a surgery to decrease the chance of seeding.
A. True(Your Answer)
B. False(Missed)
Explanation
It is used postop to destroy remaining cells.

false

It is possible to reverse changes in cell's genetic structure upon initiation?
A. True
B. False(Your Answer)

false

What is the difference between Stage III and Stage IV?
A. Limited to tissue of origin vs limited to local spread
B. Cancer in situ vs limited to local spread
C. Extensive local and regional spread vs metastasis(Your Answer)
D. Limited to tissue of orgin vs metastasis

Extensive local and regional spread vs metastasis(Your Answer)

Biology - Cancer - Subjecto.com

Biology – Cancer

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Cancer Cells

Cancer cells have a number of abnormal characteristics that prevent them from functioning in the same manner as normal cells. They divide repeatedly and form tumors in the place of origin and in other parts of the body. Cancer is actually over a hundred different diseases. However, these characteristics are common to cancer cells.

Causes and Prevention of Cancer

Whether cancer develops is partially due to inherited genes, but exposure to carcinogens such as UV radiation, tobacco smoke, pollutants, industrial chemicals, and certain viruses play a significant role also.

Diagnosis of Cancer

Cancer is usually diagnosed by certain screening procedures and by imaging the body and tissues, utilizing various techniques.

Treatment of Cancer

Surgery involving bone marrow transplants followed by radiation and/or chemotherapy has now become fairly routine. Other methods are under investigation.

Characteristics of Cancer Cells

Cancer is a cellular disease. Cancer Cells Lack Differentiation Cancer cells are nonspecialized and do not contribute to the functioning of a body part. Cancer Cells Have Abnormal Nuclei The nuclei of cancer cells are enlarged and may contain an abnormal number of chromosomes. Cancer Cells Have Unlimited Potential to Replicate Cancer cells are immortal and keep on dividing for an unlimited number of times. Cancer Cells Form Tumors Cancer cells pile on top of one another and grow in multiple layers, forming a tumor. Cancer Cells Have No Need for Growth Factors (chemical signals) Cancer cells keep on dividing, even when stimulatory growth factors are absent, and they do not respond to inhibitory growth factors. Cancer Cells Gradually Become Abnormal The process of carcinogens is a multistage process that can be divided into three phases: initiation, promotion, and progression. Cancer Cells Undergo Angiogenesis and Metastasis Tumors require a well-developed capillary network to bring nutrients and oxygen. Angiogenesis is the formation of new blood vessels. When cancer cells begin new tumors far from the primary tumor, metastasis has occurred.

Cancer Results from Gene Mutation

Proto-oncogenes encode proteins that promote the cell cycle and prevent apoptosis. Tumor-suppressor genes encode proteins that inhibit the cell cycle and promote apoptosis.

Proto-Oncogenes Become Oncogenes

When proto-oncogenes mutate, they become cancer causing genes called oncogenes. These would be considered "gain of function" mutations. Some proto-oncogenes encode growth factors or growth factor receptors.

Tumor-Suppressor Genes Become Inactive

When tumor-suppressor genes mutate, their products no longer inhibit the cell cycle nor promote apoptosis. These mutations can be called "loss of function" mutations.

Types of Cancer

Oncology is the study of cancer. Tumors are classified according to their place of origin: carcinomas are cancers of epithelial cells, sarcomas are cancers that arise in muscles and connective tissue, leukemias are cancers of the blood, and lymphomas are tumors of lymphatic tissue. Common Cancers Cancer can occur in all parts of the body, but some organs, such as the lungs, the colon/rectum, the blood, breast, and skin are more susceptible than others.

Cancer is caused by a combination of heredity and environmental factors.

Heredity Certain cancers, such as breast, lung, and colon cancers, run in families. Some childhood cancers are inherited as a dominant gene. Environmental Carcinogens A mutagen is an agent that enhances the chance of a DNA mutation. A carcinogen is an environmental agent that can trigger cancer. Carcinogens are frequently mutagenic. Radiation Ultraviolet radiation in sunlight and tanning lamps triggers the development of skin cancers. Melanoma is the spreading form of skin cancer. Radon gas can lead to lung cancer. X rays and nuclear radiation can lead to cancer. Organic Chemicals Tobacco smoke contains numerous organic chemicals that can lead to cancers of the lung, mouth, larynx, bladder, kidney, and pancreas. Pollutants Exposure to pollutants such as metals, dust, chemicals, or pesticides can increase the risk of cancer. Viruses At least four types of DNA viruses, hepatitis B and C viruses, Epstein-Barr virus, and human papillomavirus, are directly believed to cause human cancers. Dietary Choices Nutrition is emerging as a way to help prevent cancer. The consumption of fruits and vegetables, whole grains instead of refined grains, and a limited consumption of red meats are recommended. Moderate exercise is also recommended.

The earlier a cancer is detected, the more likely it can be effectively treated.

Seven Warning Signs The seven warning signs of cancer spell the word CAUTION (change in bowel or bladder habits, a sore that does not heal, unusual bleeding or discharge, thickening or a lump in breast or elsewhere, indigestion or difficult in swallowing, obvious change in wart or mole, nagging cough or hoarseness.)

Routine Screening Tests

Pap smears for cervical cancer are an example of a routine screening test. For breast cancer, routine self-exam, exam by a doctor, and mammography are recommended. Colon cancer screening involves a digital rectal exam, sigmoidoscopy, a fecal occult blood test, and colonoscopy. Diagnosis of cancer in other parts of the body may involve other types of imaging. Tumor Marker Tests Blood tests for tumor antigens/antibodies produced against tumors are called tumor marker tests. They can be used to detect first-time cancer and cancer relapses. Genetic Tests When individuals test positive for the presence of marker genes, such as the BRCA1 breast cancer oncogene, they should be vigilant for signs of cancer. Microsatellite abnormalities and the presence of telomerase indicate that cancer is present.

Standard Therapies

Surgery Surgery is sufficient for cancer in situ. Surgery followed by radiation is recommended when cancer cells may have been left behind. Radiation Therapy Ionizing radiation causes chromosomal breakage and cell cycle disruption. Therefore, dividing cells, such as cancer cells, are more susceptible to its effects than other cells. Chemotherapy Chemotherapy is used for metastatic cancers that may have spread throughout the body. Chemotherapeutic drugs kill cells during cell division. Certain types of cancers are now successfully treated by combination chemotherapy alone. Bone marrow transplants are used when a patient is to receive high doses of radiation or chemotherapy.

Newer Therapies

Immunotherapy The use of monoclonal antibodies designed to combine with receptors on cancer cells is under investigation. A cancer vaccine that stimulates the body’s immune system to attack cancer cells has promise but has yet to be highly effective. p53 Gene Therapy Adenoviruses are used to carry a normal copy of the p53 gene into cancerous tissues. Other Therapies Other therapies such as the use of antiangiogenic drugs are being investigated.

Characteristics

Lack differentiation and do not contribute to body functioning Have abnormal nuclei that are enlarged and may have an abnormal number of chromosomes Unlimited ability to divide one way is through turning on the telomerase gene that allows telomeres on chromosomes to continually be built thus allowing a cell to divide over and over again Form tumors Benign tumors are usually encapsulated and do not invade adjacent tissue while a cancerous tumor usually is not encapsulated and eventually invades surrounding tissue Can divide without growth factors Become abnormal gradually through a multistage process Undergo angiogenesis and metastasis

The 3 phases in the development of cancer cells

Initiation – a single cell undergoes a mutation that causes it to divide repeatedly Promotion – a tumor develops and cells within the tumor mutate Progression – a cell mutates in such a way that allows it to invade surrounding tissue

More characteristics

a. Cell (dark pink): acquires a mutation for repeated cell division. b. New mutations arise, and one cell (brown) has the ability to start a tumor. Cancer in situ. The tumor is at its place of origin. One cell (purple) mutates further. c. Cells have gained the ability to invade underlying tissues by producing a proteinase enzyme. d. Cancer cells now have the ability to invade lymphatic and blood vessels. e. New metastatic tumors are found some distance from the original tumor.

Angiogenesis

Angiogenesis: formation of new blood vessels to supply nutrients and oxygen to the tumor

Metastasis

Metastasis: cells move into the bloodstream or lymphatic vessels to make new tumors at distant sites from the primary tumor

Proto-oncogenes

products promote the cell cycle and prevent cell death (apoptosis

Tumor-suppressor genes

products inhibit the cell cycle and promote apoptosis

Mutations in the genes above can cause cancer, in fact proto-oncogenes that have mutated are cancer-causing genes called

oncogenes

Oncology

study of cancer

Carcinomas

Carcinomas: cancers of the epithelial tissue

Adenocarcinomas

Adenocarcinomas: cancers of glandular epithelial cells

Sarcomas

Sarcomas: cancers of muscle and connective tissues

Leukemias

Leukemias: cancers of the blood

Lymphoma

Lymphoma: cancers of lymphatic tissues

Causes of cancer

Genetics Environmental carcinogens Radiation Environmental carcinogens (tobacco smoke and pollutants) Viruses

Genetic causes of cancer

Examples of genes associated with cancer: BRCA1 and BRCA2 – tumor-suppressor genes that are associated with breast cancer RB – a tumor-suppressor gene that is associated with an eye tumor RET – proto-oncogene that is associated with thyroid cancer

mutations

Mutations of these genes predispose individuals to certain cancers but it takes at least one more acquired mutation during their lifetime to develop cancer

Environmental causes of cancer

Radiation: Environmental factors such as UV light (in sunlight or tanning lights) and x-rays can cause mutation in DNA Organic chemicals: Tobacco smoke: increases cancer of lungs, mouth, larynx and others Pollutants: substances such as metals, dust, chemicals and pesticides increase the risk of cancer Viruses: Hepatitis B & C: virus that can cause liver cancer Epstein-Barr virus: can cause Burkitt’s lymphoma Human papillomavirus: can cause cervical cancer

Protective Behaviors

Don’t use tobacco Don’t sunbathe or use a tanning booth Avoid radiation Be tested for cancer Be aware of occupational hazards Be aware of postmenopausal hormone therapy Get vaccinated

The Right Diet

Avoid obesity Eat plenty of high-fiber foods Increase consumption of foods that are rich in vitamins A and C Reduce consumption of salt-cured, smoked, or nitrite-cured foods Include vegetables from the cabbage family in the diet Drink alcohol in moderation

Seven signs

Change in bowel or bladder habits A sore that does not heal Unusual bleeding or discharge Thickening or lump in breast or elsewhere Indigestion or difficulty in swallowing Obvious change in wart or mole Nagging cough or hoarseness CAUTION

Some routine screening tests for cancer

Self-examination – monthly exams of breasts and testicles starting at age 20 Colonoscopy – every 5 years starting at age 50 Mammogram – yearly after age 40 Pap smear – should begin these 3 years after vaginal intercourse or no later than age 21

Detecting melanoma skin cancer

A – asymmetry B – border is irregular C – color varies from one area to another D – diameter is larger than 6mm

A = Asymmetry,

A = Asymmetry, one half the mole does not look like the other half.

B = Border

B = Border, irregular scalloped or poorly circumscribed border.

C = Color

C = Color, varied from one area to another; shades of tan, brown, black, or sometimes white, red, or blue.

D = Diameter

D = Diameter, larger than 6 mm (the diameter of a pencil eraser).

E = Elevated

E = Elevated above skin surface, and Evolving, or changing over time

Other ways to detect cancer

Tumor marker tests – blood tests for tumor antigens/antibodies CEA (carcinoembryonic antigen) antigen can be detected in someone with colon cancer PSA (prostate-specific antigen) test for prostate cancer Genetic tests – tests for mutations in proto-oncogenes and tumor-suppressor genes RET gene (thyroid cancer) P16 gene (associated with melanoma) BRCA1 (breast cancer) A diagnosis of cancer can be confirmed by performing a biopsy

Standard cancer treatments

Surgery – removal of small cancers Radiation therapy – localized therapy that causes chromosomal breakage and disrupts the cell cycle Chemotherapy – drugs that treat the whole body that kills cells by damaging their DNA or interfering with DNA synthesis Bone marrow transplants – transplant bone marrow from one individual to another

Newer cancer therapies

Immunotherapy – inject immune cells that are genetically engineered to bear the tumor’s antigens Passive immunotherapy – antibodies that are linked to radioactive isotopes or chemotherapeutic drugs are injected into the body p53 gene therapy – a retrovirus in clinical trial that is injected into the body where it will infect and kill only tumor cells (cells that lack p53 = tumor cells) Angiogenesis inhibition – Angiostatin and endostatin are drugs in clinical trials that appear to inhibit angiogenesis

Immunotherapy

1. Antigen-presenting cells (APCs) are removed from the patient. 2. APCs are genetically engineered to have genes for tumor antigens. 3. APCs display tumor antigens at their surface. 4. Genetically engineered cells are returned to patient. 5. APCs present tumor antigen to cytotoxic T cells, and they attack tumor cells.

A ______ gene codes for a repressor protein.
A) promoter
B) operator
C) structural
D) regulator
E) transcription

d) regulator A regulator gene codes for a repressor protein.

The promoter is ___________.
A) a short sequence of DNA where the repressor binds, preventing RNA polymerase from attaching to the promoter
B) a short sequence of DNA where RNA polymerase first attaches when a gene is to be transcribed
C) one to several genes of a metabolic pathway that are transcribed as a unit
D) a gene that codes for a repressor protein
E) any dominant gene

D) a gene that codes for a repressor protein The promoter is a short sequence of DNA where RNA polymerase first attaches when a gene is to be transcribed.

Each cell contains a full complement of genes but only certain genes are active at any one time.
A) True
B) False

true

A regulator gene located inside the operon codes for a promoter protein that can bind to the operator and switch on the operon.
A) True
B) False

false

The operon model explains a means of transcriptional control in bacteria.
A) True
B) False

true

Which of the following is NOT true concerning control of gene expression in eukaryotic cells?
A) Transcriptional control is the most important factor.
B) Transcription factors help RNA polymerase bind to a promoter.
C) Transcription activators binding to enhancers can speed up transcription.
D) Part of transcriptional control includes the processing of mRNA before it leaves the nucleus.
E) All of the above are correct.

D) Part of transcriptional control includes the processing of mRNA before it leaves the nucleus. The processing of mRNA before it leaves the nucleus occurs after transcription has taken place.

All mRNA molecules exist for the same amount of time within a cell.
A) True
B) False

false

Which of the following is NOT true regarding protein activity?
A) All proteins are active immediately after being formed.
B) Proteasomes are protein complexes responsible for degrading proteins.
C) Proteins will fold into a three dimensional structure after being synthesized.
D) Some amino acids may need to be removed before a protein becomes functional.
E) Protein activity is usually controlled by feedback control.

A) All proteins are active immediately after being formed.

Ordinarily, cells with damaged DNA undergo ______ or programmed cell death.
A) apoptosis
B) tumor-suppression
C) differentiation
D) angiogenesis
E) metastasis

A) apoptosis

Cancer cells exhibit uncontrolled and disorganized growth.
A) True
B) False

true

Formation of new blood vessels is required to bring nutrients and oxygen to cancerous tumors.
A) True
B) False

true

Cancer cells cannot enter the cell cycle and therefore are mortal.
A) True
B) False

false cancer cells enter the cell cycle repeatedly, and in this way they are immortal.

______ are cancer-causing genes.
A) Metastases
B) Mutagens
C) Carcinogens
D) Oncogenes
E) Homozygous recessive genes

D) Oncogenes Oncogenes are cancer-causing genes. Metastases are clusters of cancerous cells that have broken away and settled elsewhere.

A cell contains many ___________ where one mutation can cause them to become oncogenes.
A) metastases
B) tumor-suppressor
C) benign tumors
D) proto-oncogenes
E) carcinogens

D) proto-oncogenes A cell contains many proto-oncogenes where one mutation can cause them to become oncogenes. Metastases are clusters of cancerous cells that have broken away and settled elsewhere.

Proto-oncogenes promote the cell cycle and _____ genes inhibit the cell cycle.
A) recessive
B) tumor-suppressor
C) benign
D) proto-oncogenes
E) carcinogens

B) tumor-suppressor Proto-oncogenes promote the cell cycle and tumor-suppressor genes inhibit the cell cycle.

Which of these characteristics is typical of cancer cell?
A) Cancer cells lack contact inhibition.
B) Cancer cells induce angiogenesis.
C) Cancer cells lack specialization.
D) Cancer cells can metastasize.
E) All of these are correct

E) All of these are correct Cancer cells lack contact inhibition, induce angiogenesis, lack specialization, and can metastasize.

A ________ is an environmental agent that can contribute to the development of cancer.
A) mutagen
B) fibrinogen
C) carcinogen
D) factor

A) mutagen A carcinogen is an environmental agent that can contribute to the development of cancer.

some examples of carcinogens are _________.
A) certain organic chemicals
B) radiation
C) viruses
D) All of these are correct

D) All of these are correct

Which DNA virus has been linked to a type of human cancer?
A) hepatitis B virus
B) human papillomavirus
C) Epstein-Barr virus
D) All of the above.

D) All of the above.

The pap smear is a test for ________ cancer.
A) colon
B) cervical
C) breast
D) ovarian
E) liver

B) cervical

The standard methods of treatment for cancer are _________.
A) surgery
B) radiation
C) chemotherapy
D) All of the above

D) All of the above Surgery, radiation, and chemotherapy are the standard methods of cancer therapy.

most chemotherapy drugs kill cells by damaging ___________.
A) DNA
B) protein
C) nearby blood vessels
D) the cell membrane
E) All of the above

A) DNA Most chemotherapy drugs kill cells by damaging their DNA or interfering with DNA synthesis.

angiogenesis

Formation of new blood vessels; one mechanism by which cancer spreads

apoptosis

Programmed cell death involving a cascade of specific cellular events leading to death and destruction of the cell.

carcinogen

Environmental agent that causes mutations leading to the development of cancer.

chemotherapy

way to catch cancer cells that have spread throughout the body; kills cells by damaging their DNA or interfering with DNA synthesis.

enhancer

Elements that regulate transcription from nearby genes. Function by acting as binding sites for transcription factors.

genetic test

Test that looks for genetic mutations in proto-oncogenes and tumor-suppressor genes; makes it possible to detect the likelihood of cancer.

growth factor

Chemical signal that regulates mitosis and differentiation of cells that have receptors for it; important in such processes as fetal development, tissue maintenance and repair, and hematopoiesis; sometimes a contributing factor in cancer.

leukemia

Cancer of the blood-forming tissues leading to the overproduction of abnormal white blood cells.

lymphoma

Cancer of lymphatic tissue. 5

metastasis

Formation of new tumors distant from the primary tumor.

oncogene

Cancer-causing gene.

operon

Cluster of bacterial genes along with the DNA sequences that control their transcription.

proto-oncogene

Encodes for proteins that promote the cell cycle and prevent apoptosis.

regulatory gene

An an operon, a gene that codes for a protein that regulates the expression of other genes.

repressor

In an operon, protein molecule that binds to an operator, preventing transcription of structural genes.

reproductive cloning

Fenetically identical to the original individual.

signal transduction pathway

Activation and inhibition of intracellular targets after binding of growth factors.

telomere

Sequence of bases at the end of chromosomes that keeps them from fusing with one another.

therapeutic cloning

Used to create mature cells of various cell types. Also, used to learn about specialization of cells and provide cells and tissue to treat human illnesses

transcription activator

Protein that speeds transcription.

transcription factor

Protein that initiates transcription by RNA polymerase and thereby starts the process that results in gene expression.

tumor marker test

Blood test for tumor antigens/antibodies.

tumor-suppressor gene

Gene that codes for a protein that ordinarily suppresses cell division; inactivity can lead to a tumor.

Sigmoidoscopy is a test for _______ cancer.

colon

Mutated tumor-suppressor genes cause _____.

d. Both a and b are correct.

Which of the following is a correct sign of possible malignant melanoma?

irregular border of a mole

_______ involves genetically engineered antigen-presenting cells that give tumor antigens to cytotoxic T-cells that kill the tumor cells.

Immunotherapy

Most chemotherapeutic drugs kill cells by damaging _______.

DNA

______ is an X-ray study of the breast used to detect tumors too small to be felt.

mammography

An agent that causes mutation is a/an:

mutagen

Which of the following is NOT a warning signal of possible cancer?

cold like symptoms

Which step in carcinogenesis is correctly matched with its description?

Initiation – a single cell has a mutation that allows it to divide repeatedly.

A _______ is an environmental agent that can contribute to the development of cancer.

carcinogen

Which cancer classification is NOT matched with its description?

sarcomas – cancer of the liver

What is the correct order of steps in carcinogenesis?

initiation, promotion, progression

The formation of new blood vessels is _________.

angiogenesis.

What DNA virus has been linked to a type of human cancer?

All of these are correct.

In cancer cells, oncogenes cause:

both A and B Oncogenes can cause both an excess of Cyclin D and an excess of p53 inhibitors

The most common cancer in males is:

prostate

What percent of all cancers are thought to be related to the usage of tobacco products?

80

___ is the study of cancer.

oncology

the most common cancer in females is:

breast

Cancer in situ _______.

is found in one place

Which of these characteristics is typical of cancer cells?

all

Cancer cells produce _____ enzymes that degrade membranes which allows movement into other tissues.

proteinase

The standard methods of treatment for cancer are _______.

All of these are correct.

Proto-oncogenes encode for proteins that _____.

Both a and b are correct. Answer Feedback: Proto-oncogenes encode for proteins that promote the cell cycle and prevent apoptosis

Which type of cancer causes the most deaths in both males and females?

lung

A(n) ______ is a cancer-causing gene.

oncogene

Oncogenes frequently involved in human cancers belong to the ______ gene family.

ras

Which of the following is NOT an environmental carcinogen?

high fiber food Answer Feedback: Examples of carcinogens include certain organic chemicals, radiation, and viruses

The PAP test is used to test for _____ cancer.

cervical

Tumors that fail to have cells undergoing apoptosis lack an active _________ gene.

p53

Identify the characteristics that are typical of cancer cells?
A) cancer cells lack contact inhibition
B) cancer cells induce angiogenesis
C) cancer cells lack differentiation
D) All of these are correct.

D

What is the function of telomerase?
A) rebuild telomere sequences
B) destroy telomere sequences
C) connect different telomere sequences
D) separate different telomere sequences

A) rebuild telomere sequences

A normal cells typically divides 60 to 70 times before it dies while cancer cells:
A) divide an unlimited number of times
B) divide twice that amount
C) may divide 60-70 times
D) are unable to divide

A) divide an unlimited number of times

When cancer cells undergo metastasis
A) tumors release growth factors.
B) tumors increase in size.
C) tumors have nondifferentiated cells.
D) cancer spreads throughout the body.

D) cancer spreads throughout the body.

Which of the following proteins acts as a transcription factor involved in turning on the expression of genes whose products are cell cycle inhibitors?
A) p14
B) p53
C) p76
D) p22

B) p53

Which of the following is not considered part of the process by which cancer cells gradually become abnormal?
A) Initiation
B) Promotion
C) Transcription
D) Progression

C) Transcription

A/an ________ tumor is usually encapsulated and noninvasive.
A) benign tumor
B) malignant tumor
C) neoplasm
D) proteolytic

A) benign tumor

The ________ predisposes an individual to thyroid cancer.
A) HOM
B) HOX
C) RB
D) RET

C) RET

___ is a type of skin cancer which tends to metastasize and can be fatal.
A) Basal cell carcinoma
B) Lymphoma
C) Sarcoma
D) Melanoma

D) Melanoma

Choose the following that is not associated with the American Cancer Society’s caution warning signals.
A) thickening or lump in breast
B) indigestion or difficulty swallowing
C) obvious change in wart or mole
D) All of the choices are associated.

D

The PSA test is used to detect _____________.
A) colon cancer
B) liver cancer
C) prostate cancer
D) breast cancer

C) Prostate

Which of the following has been proposed as future cancer therapy?
A) monoclonal antibodies
B) p53 gene therapy/induced tumor apoptosis
C) angiogenesis inhibition
D) All of the choices are correct.

D All

Cancer cells have no need for growth factors

chemical signals between cells tell them whether or not they should be dividing. These chemical cells called growth factors are of two types: stimulator growth factors and inhibitory growth factors. Cancer cells keep dividing, even when stimulatory growth factors are absent and they do not respond to inhibitory growth factors

what are the four leading types of cancer in men and women?

Men: prostate, lung and bronchus, colon and rectum, urinary bladder Women: breast, colon and rectum, uterine corpus, non-hodgkin lymphoma

proto oncogenes become oncogenes

when proto oncogenes mutate, they become cancer causing genes called oncognes. Whatever a proto oncogene does an oncogene does better

whereas _____________ stimulates the cell cycle, ____________________ inhibit cell cycles

proto oncogenes, tumor suppressor genes

Growth factors lead to

increased cell division, the functioning of cyclin proteins, progression through the cell cycle

which of the following is not true of the gene p53

normally p53 functions to stop the cell cycle and initiate repair enzyes when necessary

which association is not correct?

mutated tumor suppressor genes – code for cyclin and proteins that inhibit the activity of p53

following each cell cycle, telomers

get shorter

cyclin

a protein molecule that hsas to be present for a cell to proceed from interphase to mitosis. When cancer develops, the cell cycle occurs repeatedly due to mutations in proto oncogenes and tumor suppressor genes

differentiation

the process of cellular development by which a cell acquires a specific structure and function. Cancer cells do not contribute to the functioning of the body like, for example, red cells that are differentiated cells in the circulatory system

nuclei of cancer cells

enlarged, contain abnormal number of chromosomes – the nuclei takes up most of the cell. The chromosomes are defective. Some chromosomes may be duplicated or deleted. Gene amplification are extra copies of specific genes. Usually damaged DNA cells undergo apoptosis, or programmed cell death. Cancer cells do not even though they are abnormal.

telomere proteins

chromosomes end with special repetitive DNA sequences called telomeres. Specific proteins bind in both normal and cancerous cells. They protect the ends of chromosomes from DNA repair enzymes. Enzymes effectively repair DNA in the center of the chromosome, they tend to bind together at the naked ends of chromosomes. In normal cells the telomeres get shorter after each cycle. Repair enzymes cause chromosome ends to bind together and apoptosis occurs causing the cell to die. Telomere is an enzyme. The gene that codes for telomere is constantly turned on in cancer and they constantly rebuild. The telomeres remain at constant length and keep dividing over and over.

tissues that divide frequently are more likely to become cancerous in the

respiratory and digestive tracts

initiation

a single cell undergoes a mutation that causes it to begin to divide repeatedly

promotion

a tumor develops and the tumor cells continue to mutate and divide

progression

one cell undergoes a mutation that gives it selective advantage over the other cells. The process is repeated until a cell has the ability to invade surrounding areas

angiogenesis and metastasis

angiogenesis the formation of new blood vessels – low oxygen content in the middle of a tumor turns on gene coding for angiogenic growth factors that diffuse into nearby tissues causing new vessels to form. To metastasize cancer cells make make their way across the basement membrane and invade a blood or lymphatic vessel – invasive cancer cells are sperm shaped and don’t look normal.

Cancer cells produce proteinase enzymes

that degrade the basement membrane and allow them to invade underlying tissue. Not many cancer cells achieve metastasis, only 1 in 10,0000 – lowers prognosis

cyclin is a protein molecule that has to be present for a cell to proceed from interphase to mitosis

when cancer develops the cell cycle occurs repeatedly

proto oncogenes are proteins that inhibit the cell cycle and preent apopotosis

like the gas pedal on a car because they cause acceleration of the cell cycle

tumor suppressor genes code for proteins that inhibit the cell cycle and promote apopotosis

they are like the brakes on a car because they inhibit acceleration

several proto oncongenes code for Ras proteins that promote mitosis by activating cyclin

ras oncongenes are typically found in many different types of cancer. Cyclin D is a proto oncogene that codes for cyclin directly. When this gene becomes oncogne cyclin is readily available all the time

p53 is a protein that activates repair enzymes

p53 turns on genes that stop teh cell cycle from proceeding. If repair is impossible the p53 protein promotes apoptosis – programmed cell death. When the proto oncogene becomes an oncogene no p53 will be available regardless of how much is made. Many turos are lacing in p53 activity

Bax

promotes apoptosis. When Bax mutates, Bax protein is not present and apoptosis is less likely to occur. The bax gene contains a line of eight consecutive G bases in its DNA. When the same base molecules are lined up in this fashion the gene is more likely to be subject to mutation

1 in 3 americans will deal with cancer in their lifetime

carcinomas are cancers of the epithelial tissue – tumors are classified by their point of origin. Adenocarcinomas are cancers of glandular epitheilial cells. Carcinomas include skin, breast, liver, pancreas, intestines, lung, prostate and thyroid. Sarcomas are muscle and connective tissue. Leukemias are cancer of the blood. Lymphomas are cancers of lymphatic tissue. Blastoma is cancer composed of immature cells.

Transposons

small, mobile sequences of DNA that have the ability to move throughout the genome. They are closely related to retroviruses. Also known as jumping genes. our genome has over 3.4 billion nucleotides. There have been cases where a transposon has caused a loss of cell cycle control ad can be factor in development of cancer and other diseases such as hemophilia ad muscular dystrophy

radiation is localized therapy

ionizing radiation causes chromosomal breakage and cell cycle disruption. Cancer of the cervix, larynx and early stages of prostate & hodgkins disease are treated with radiation alone. Xrays and gamma rays are the mainstays of radiation therapy but protons and neutrons also work well. Proton beams can be aimed like a rifle. Side effects are weakness and fatique, dry mouth, nauseau, diarrhea affect digestive tract. Dry, red or irritated skin or burns, hair loss at the treatment site can be permanent, side effects usually temporary

chemotherapy used for cancer cells that have spread

treats entire body. Kills cells by damaging DNA or interfering with DNA synthesis.

alkylating agents

interfere with the growth of cancer cells by blocking the replication of DNA

antimetabolites

block enzymes needed by cancer cells to live and grow

antitumor antibiotics

different from those used to treat bacterial infections – interfere with DNA, blocking certain enzymes and cell division and changing cell membranes

mitotic inhibitors

inhibit cell division or hinder certain enzymes necessary in cell reproduction process

nitrosoureas

medications that impede the enzymes that help repair DNA

chemo is specifically designed for the particular cancer

in some cancers a small portion of chromosome 9 is missing, therefore, DNA metabolism differs in the cancerous cells compared with normal cells. Specific chemo for the cancer can exploit this metabolic difference and destroy the cancer cells

taxol

extracted from bark of the pacific yew tree is effective against ovarian, breast, head and neck tumors. It interferes with microtubules needed for cell division. Taxoids were developed by chemists may be more powerful and have fewer side effects than taxol

survival rate for leukemia

in children is 80%

hodgkins

used to kill 2 out of 3 patients, new medication combinations can wipe out the disease in a matter of months. 3 out of 4 patients achieve a cure

multidrug resistance

chemo can fail because cancer cells become resistant to one or several chemo meds because a plasma membrane carrier pumps the drug out of the cancer cell before it can be harmed.

bone marrow transplants

sometimes done along with chemo. Red bone marrow contains large populations of dividing cells. Red bone marrow is prone to destruction by chemo drugs. In bone marrow transplantation a patients stem cells are harvested and stored before chemo begins. high doses of radiation or chemo drugs are given in a relatively short time. This prevents multidrug resistance from occurring. Stored stem cells are returned to the patient by injection, they make they way to the bony cavities and resume blood cell formation

melacine

a vaccine contains broken melanoma cells from two differnt sources is under investigation for use against melanoma. another idea is to use immune cells genetically engineered to bear the tumor’s antigens.When returned to the body they produce cytokines. Cytokines stimulate the body to attack tumors. Altered immune cells present the tumor antigen to cytotoxic T cells when then go forth and destroy tumor cells in the body.

Passive immunotherapy

monoclonal antibodies have the same structure because they are produced by the same plasma cells. some monoclonal antibodies are designed to zero in on the receptor proteins of cancer cells. To increase the killing power of monoclonal antibodies they are linked to radioactive isotopes or chemotherapeutic drugs

gene therapy

p53 gene expression is neeed for only 19 hours to trigger apoptosis, programmed cell death. the p53 gene seems to trigger cell death only in cancer cells. elevating p53 levels in normal cells doesn’t do any harm, because apoptosis requires extensive DNA damage

adenoviruses

when adenoviruses infect a cell they produce a protein that inactivates p53. In a cleverly designed procedure, investigators genetically engineered an adenovirus that lacks the gene for this protein. Now the adenovirus can infect and kill only cells that lack a p53 gene – tumor cells. Injected adenovirus spreads through the cancer killing tumor cells as it goes – clinical trials have begun

Antiangiogenic drugs

confine tumors by breaking up the network of new capillaries in the vicinity of the tumor. Two drugs called angiostatin and endostatin inhibit angiogenesis in laboratory animals

cancer cells tend to be motile

they have a disorganized internal cytoskeleton and lack intact actin filament bundles.

to grow larger than about a billion cells (about the size of a pea)

a tumor must have a well developed capillary network to bring it nutrients and oxygen – angiogenesis is the formation of new blood vessels.

to lesson side effects of chemo

nausea, vomiting, diarrhea, weight loss, hair loss, anxiety, depression, extreme fatigue. Antiemetic drugs alleviate nausea and vomiting. Genetically engineered erythropoietin helps stimulate red blood cell production to reduce fatigue. Marinol (like marijuana) stimulates appetite and helps with weight loss. Hair loss can be minimized by cryotherapy – applying cold packs on the scalp during treatment. Cold slow the metabolic rate of hair follicles so more follicles survive the treatment. Antidepressants and anti anxiety medications for depression. Yoga, meditation and tai chi help to relax. Hypnosis can be tried. Aromatherapy, massage and music ease tension and stress by stimulating pleasure centers in the brain. Exercise produces endorphins, the brain’s pain relieving neurotransmitters

leukemia, lymphomas and testicular cancer

are successfully treated with chemo alone

routine screen testing

self examination followed by physician exam (ABCDE) pap test for cervical cancer – examine cells under microscope for abnormalities colon cancer – digital rectal exam, flexible ssigmoidoscopy with a thin, pliable, lighted tube, stool blood test, colonoscopy – polyps are destroyed by lasers blood tests detect leukemia urinalysis diagnosis bladder cancer breast – mamography Computerize axial tomography (CAT scan) to locate size and location of tumors MRI useful for analyzing tumors in tissues surrounded by bone, brain or spinal cord radioactive scan after a radioactive isotope is administered can reveal abnormal isotope accumulation due to a tumor ultrasound confirm tumors of stomach, prostate, pancreas, kidney, uterus and ovary biopsy laparoscopy – permits viewing of body parts

tumor marker tests

blood tests for antigens and/or antibodies. Tumors release substances that provoke antibody response – if a patient has colon cancer, it is possible to use the presence of an antigen called carcinoembryonic antigen (CEA) to detect relapses. When CEA levels rise, tumor growth has occurred Tumor marker tests can be used for early cancer diagnosis Prostate specific antigen – PSA CA-125 test for ovarian cancer Alpha fetoprotein (AFP) test for liver tumors

Genetic tests

tests are available that signal the liklihood of cancer. Tests are available for colon, bladder, breast, thyroid and melanoma. A mutated RET gene means that thyroid cancer is present or may appear in the future. Mutated p16 gene is associated with melanoma. Breast cancer gene 1 = presence of BRCA1 Microsatellites are small regions of DNA that always have two (di-), three (tri-) or four (tetra-) nucleotide repeats. They compare the number of nucleotide DNA repeats in a lymphocyte microsateelite with the number ina microsatelite of a cell found in urine – the number of repeats is less in the cell from urine, a bladder tumor is suspected

telomerase

the enzyme that keeps telomeres a constant length in cells. The gene that codes for telomerase is turned off in normal cells but is active in cancer cells, if the test for the presence of telomerase is positive the cell is cancerous

Why is it important to catch cancer growths so soon?
A.
To interrupt initiation.
B.
To stop benign cells turning to malignant cells.
C.
To interrupt promotion of altered cells.
D.
To increase the metasis profile.

C. To interrupt promotion of altered cells.

Which are sites of Metastasis?
A.
Lungs
B.
Brain
C.
Bone
D.
Liver
E.
All the above.

All the above.

More abnormal, moderately differentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade II

Tom’s growth has come back. The lab report shows that the growth is encapsulated and partially differentiated. There is no metasis and is rather large. What type of growth does Tom most likely have?
A.
Benign
B.
Malignant

Benign

Naturally occurring in protein used to prevent cancer cells from proliferating; interferes with the ability of cancer cells to replicate.
A.
Interferons
B.
Interleukins
C.
Attached radioactive substances

Interferons

Mindy has had radiation for a tumor on her tibia. What can she expect?
A.
Nausea
B.
Diarrhea
C.
Myelosuppression
D.
Cystitis

Myelosuppression

The maximum time a nurse should be in a room of a pt with internal radiation is:
A.
30 min/shift
B.
1 hr/shift
C.
30 min/4 hrs
D.
no time limit if shielding is in place

30 min/shift

What is the cause of generalized weakness and anorexia after being treated with radiation?
A.
Destruction of normal cells
B.
Waste products of cell destruction.
C.
Toxins released from cancer cells trying to survive.
D.
Natural effects of radiation exposure.

Waste products of cell destruction.

When a pt is given unsealed sources of radiation, what principles should be followed?
A.
Distance
B.
Shielding
C.
Time
D.
All the above

all

Mindy is a 5 year old girl with cancer. What is the best way to talk to her about her treatment?
A.
With objects or drawings to illustrate.
B.
Conversation about what is happening as she can handle concepts.
C.
Discussing peer status and body imagine is important.

With objects or drawings to illustrate.

Cancer cells do not have the ability to develop new blood vessels and don’t need oxygen but needs nutrients to survive.
A.
True
B.
False

false

When should a pt be given Zofran?
A.
30 minutes before a meals and at bedtime
B.
30 minutes after meals and at bedtime
C.
30 minutes before chemortherapeutic agents.
D.
30 minutes after giving chemotherapeutic agents.

30 minutes after giving chemotherapeutic agents.

Cancer cells can easily survive in the blood and attach to body cavities.
A. True(Your Answer)
B. False(Missed)
Explanation
The turbulent blood flow must be survived by the cancer cell.

false

The pt understands cancer cells when the pt states:
A. Cancer cells uncontrollably dived.(Missed)
B. Cancer is a death sentence.
C. Mature cells function until they die.
D. Cancer cells are more cohesive than normal cells.

Cancer cells uncontrollably dived

Mucositis is:
A.
very painful
B.
ulceration of the tongue, mouth, esophogeal, GI tract
C.
disruption of bone tissue
D.
A&B
E.
All the above

A&B

Slightly different from normal cells, well differentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade I

Solid tumors from muscle, bone, fat and other connective tissue
A.
Carcinoma
B.
Sarcoma
C.
Lymphoma
D.
Leukemia

Sarcoma

Mary is on chemotherapy. Her labs come back with a WBC of 2000 and her neutrophils are 20%. She has a fever of 100.6. Is this a medical emergency?
A.
Yes
B.
No

yes

Solid tumors from epithelial tissue
A.
Carcinoma
B.
Sarcoma
C.
Lymphoma
D.
Leukemia

Carcinoma

Matt has had radiation therapy for a tumor in his neck. What can Matt expect?
A.
Change in taste
B.
Increased saliva production
C.
Hair Loss
D.
Dyspnea

hair loss

In order for metastasis to take place, cells must stop and adhere at a secondary to proliferate.
A.
True
B.
False

true

Very abnormal, poorly differentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade III

The nurse understands the side effects of Zofran when the nurse states:
A.
Insomnia
B.
Constipation/Diarrhea
C.
Restlessness
D.
Must be assessed for extrapyramidial effects

Constipation/Diarrhea

side effects of Reglan

B. Drowsiness

Primitive and undifferentiated
A.
Grade I
B.
Grade II
C.
Grade III
D.
Grade IV

Grade IV

Carry’s lab report came back with a poorly differentiated growth that is encapsulated. There is a marked increase in vascularity and is infiltrating. What type of growth is this most likely?
A.
Benign
B.
Malignant

malignant

TNM Classification System refers to:
A.
Tumor (primary)
B.
Lymph Node involvement
C.
Metastasis
D.
All the above.

all

Nick has had radiation treatment for a tumor in his lung. What can Nick expect?
A.
Asthma
B.
Bronchitits
C.
Dyspnea
D.
Pneumonitis

Dyspnea

Lori is talking with her nurse about factors that promote cancer. Lori weighs 245 lbs and eats a lot of fast food. She is on large doses of estrogen for another condition and is 45 years old. Lori understands her risks when she states:
A.
My diet and weight predispose me to cancer.
B.
My parents didn’t have cancer so I won’t have it.
C.
Self examination is important for finding and changes.
D.
It’s too late to make lifestyle changes because of my age, the damage is done.

My diet and weight predispose me to cancer.

Which is the most common route of metastasis?
A.
Blood
B.
Lymph System
C.
Surgery
D.
Trauma to a tumor

lymph

Chemotherapy usually kills 100% of a tumor.
A.
True
B.
False

false

Increased growth of tumor including invasion and metasis is called:
A.
Initiation
B.
Promotion
C.
Progression

progression

The nurse understands Decadron when the nurse states:
A.
Can cause euphoria
B.
Can cause insomnia
C.
Can cause mild fluid retention
D.
Monitor electrolytes and glucose
E.
All the above.

all

Colony Stimulating Factors (CSF) do what?
A.
Stimulates blood cell production by the bone marrow
B.
Stimulates NK cell production
C.
Stimulates T4 cell production
D.
Stimulates non proliferation agents in cancer cells.

Stimulates blood cell production by the bone marrow

The lab report comes back on the pt showing a non encapsulated growth that is poorly differentiated. The growth also shows that they are unlike the parent cell. What type of growth is this most likely?
A.
Benign
B.
Malignant

malignant

Naturally occuring but not at therapeutic levels. Enhances natural killer cell activity.
A.
Interferons
B.
Interleukin
C.
Attached radioactive substances

Interleukin

What does it mean to treat a disease partially and insofar as possible, but not cure it completely?
A. Control
B. Palliation(Your Answer)
C. Stay
D. Long Term Viability

. Palliation(Your Answer)

Radiation therapy is used to treat a tumor before a surgery to decrease the chance of seeding.
A. True(Your Answer)
B. False(Missed)
Explanation
It is used postop to destroy remaining cells.

false

It is possible to reverse changes in cell’s genetic structure upon initiation?
A. True
B. False(Your Answer)

false

What is the difference between Stage III and Stage IV?
A. Limited to tissue of origin vs limited to local spread
B. Cancer in situ vs limited to local spread
C. Extensive local and regional spread vs metastasis(Your Answer)
D. Limited to tissue of orgin vs metastasis

Extensive local and regional spread vs metastasis(Your Answer)

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