Quiz | CancerQuest

Which of the following statements about Ras is FALSE?

A.

It binds GTP in performing its normal function.

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B.

In a healthy cell it breaks up and releases GTP, allowing the cell to stop dividing.

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C.

It is involved in many types of cancer, including pancreatic, colon and ovarian.

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D.

Overexpression and amplification of ras can lead to decreased cell proliferation.

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E.

The most common transition from proto-oncogene to oncogene occurs through a point mutation.

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Which of the following is a similarity between oncogenes and tumor suppressors?

A.

They both control cell division.

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B.

The loss of function of a single copy of either leads to problems.

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C.

One mutant copy of either will cause problems.

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D.

Both include growth factors that promote cell division.

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E.

All of the above.

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Common functions for tumor suppressors include which of the following?

A.

DNA damage repair, prevention of apoptosis, and transmission of nervous impulses

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B.

Promotion of apoptosis, DNA damage repair, and control of transcription factors

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C.

Prevention of apoptosis, control of transcription factors, and DNA damage repair

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D.

Transmission of nervous impulses, promotion of apoptosis, and DNA damage repair

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E.

Transmission of nervous impulses, control of transcription factors, and DNA damage repair

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Which of the following is NOT a tumor suppressor gene?

A.

Rb

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B.

p53

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C.

APC

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D.

myc

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E.

BRCA

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Mutations in tumor suppressor genes cause problems by ______.

A.

Causing the protein products to lose function

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B.

Causing the protein products to gain functions

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C.

Causing the gene to produce too much protein product

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D.

Causing the gene to produce oncogene products

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E.

Preventing the genes from activating proto-oncogenes

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The tumor suppressor, p53, is involved in all the following cellular processes EXCEPT:

A.

Promoting transcription of certain genes, including p21

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B.

Triggering programmed cell death

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C.

Monitoring the health of a cell and its DNA

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D.

Preventing cell proliferation

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E.

p53 is involved in all of the above

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Which of the following statements about p53 is FALSE?

A.

Mutations in it are always sporadic, and never inherited.

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B.

It is normally present in every cell type.

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C.

It can be inactivated by some viruses.

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D.

It is one of the most commonly mutated genes in tumors.

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E.

It is one of the many genes that controls the cell cycle.

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Which of the following oncogenes (encoding for a tyrosine kinase) was first identified in an acutely transforming chicken retrovirus?

A.

Src

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B.

Myc

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C.

Ras

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D.

Bcl-2

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E.

h-Tert

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Mutations in the APC gene are most commonly associated with what type of cancer?

A.

Skin

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B.

Brain

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C.

Breast

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D.

Pancreatic

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E.

Colon

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Which of the following genes is often defective (mutated) in individuals with a genetic predisposition to forming colorectal cancer?

A.

BRCA1 gene

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B.

hTERT gene

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C.

APC gene

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D.

BRCA2 gene

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E.

p53 gene

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___________ is a type of familial colorectal cancer associated with the formation of numerous colonic polyps.

A.

Hereditary Non-Polyposis Colorectal Cancer (HNPCC)

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B.

Gene Linked Colorectal Cancer (GLCC)

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C.

Multiple Polyp Colorectal Cancer (MPCC)

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D.

Juvenile Polyposis

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E.

Familial Adenomatous Polyposis (FAP)

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Cancer is caused by mutations in genes, tumor suppressors and proto-oncogenes, that are normally involved in:

A.

Regulation of cell division.

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B.

Transmission of nervous impulses.

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C.

Production of antibodies.

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D.

Excretion of waste products.

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E.

Digestion of excess proteins.

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Cancer Genes

Which of the following are NOT found in genetically normal cells?

A.

Tumor suppressors

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B.

Proto-oncogenes

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C.

Oncogenes

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D.

Proteins that stimulate cell division

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E.

Proteins that inhibit cell division

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Cancer Genes

Oncogenes are genes whose protein products ______.

A.

Are involved in DNA repair

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B.

Enhance the viability/mitosis of cells

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C.

Cause cells to stop dividing

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D.

Prevent the action of tumor suppressors by inhibiting transciption

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E.

Do not serve any function in cancer cells

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Cancer Genes

A defective oncogene is a damaged version of a ______ and is characterized by its ______.

A.

Proto-oncogene; inability to be transcribed into RNA

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B.

Genome; lack of protein production

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C.

Genome; unresponsiveness to deactivation signals

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D.

Proto-oncogene; unresponsiveness to deactivation signals

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E.

Proto-oncogene; lack of protein production

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Cancer Genes

What is a main function of Rb?

A.

Transcription factor for p21, a protein that stops cell proliferation

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B.

Binds and inhibits the activity of a transcription factor that, when not bound, stimulates cell division

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C.

Cell surface protein that binds growth factors and promotes the cell cycle

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D.

Pigment molecule that prevents eye cancers

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E.

Protein channel in the cell membrane that allows ATP to travel from one side to the other

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Which of the following statements about the Bcl-2 gene is FALSE?

A.

It is involved in B cell lymphoma.

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B.

It opposes myc''s pro-apoptotic action.

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C.

Overexpression of Bcl-2 can decrease the success of treatments that induce apoptosis.

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D.

Overexpression promotes metastasis of some cancers.

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E.

Its main oncogenic function is to promote DNA synthesis.

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Which of the following most appropriately describes the BRCA genes?

A.

They code for protein kinases that promote progression through the cell cycle

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B.

They are mutated only in inherited breast cancer

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C.

BRCA is another name for p53

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D.

They are involved in DNA repair

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E.

They code for transcription factors for genes that prevent apoptosis

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Which tumor suppressor gene is mutated in over 50% of cancers?

A.

p23

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B.

p33

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C.

p43

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D.

p53

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E.

p63

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The p53 gene has the important role of cellular homeostasis because it has the power to _________.

A.

Halt mitosis

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B.

Lead to repair of damaged DNA

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C.

Trigger cell death or apoptosis

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D.

A and B

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E.

All of the above are correct

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Retinoblastoma is a cancer of the _____.

A.

Kidneys

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B.

Eyes

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C.

Ears

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D.

Stomach

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E.

Lungs

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Which of the following statements about HER-2/neu is TRUE?

A.

It is involved in maintaining telomere length.

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B.

It is a tumor suppressor that prevents cell division by inducing apoptosis.

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C.

It codes for a cell-surface protein that interacts with growth factors and is thought to cause increased cell division.

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D.

It codes for a membrane-associated protein that helps to prevent apoptosis by activating caspases.

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E.

It codes for a transcription factor that is thought to promote the expression of genes that inhibit cell proliferation.

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Which enzyme is most directly involved in maintaining the ends of chromosomes?

A.

ATPase

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B.

Telomerase

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C.

Lactase

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D.

Senescase

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E.

Src tyrosine kinase

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In which of the following cells would you most expect telomerase to be expressed?

A.

Cancer cells and elderly individual's cells

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B.

Fetal cells and normal adult cells

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C.

Fetal cells and cancer cells

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D.

Normal adults cells and cancer cells

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E.

Normal adult cells and elderly individual cells

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Which of the following statements best describes hTert, the gene that codes for telomerase?

A.

Tumor suppressor, because maintaining chromosome length is necessary throughout a person's life.

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B.

Tumor suppressor, because there must be two mutant copies of it in a cell to cause cancer.

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C.

Proto-oncogene, because overexpression can lead to unregulated cell growth.

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D.

Proto-oncogene, because expression in fetal cells causes cancer.

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E.

Choices (a) and (b).

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Which of the following oncogenes is incorrectly paired with its function?

A.

hTERT : enzyme in DNA replication.

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B.

ras : transcription factor.

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C.

HER-2/neu : growth factor receptor.

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D.

src : receptor-associated tyrosine kinase.

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E.

Bcl-2 : membrane-associated protein involved in preventing apoptosis.

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All of the following are examples of oncogene functions EXCEPT:

A.

Preventing DNA synthesis.

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B.

Preventing apoptosis.

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C.

Helping cells divide by maintaining chromosome ends.

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D.

Receiving or passing on growth factor signals.

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E.

Acting as transcription factors.

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