cancer biology exam one

which of the following are NOT hallmarks of cancer?

induction of cell death and tumor promoting inflamation

which one of the following statements regarding the phenotype of transformed cells is false?

they cannot grow in low serum

which one of the following statements correctly describes why there has been an increase in the number of cases of cancer in recent years?

people are living longer

what phase of clinical trials of a new cancer drug examines a drug’s effectiveness and compares its efficacy to conventional treaments?

phase III

which one of the following statements describes the effect of most cytotoxic chemotherapies upon cancer cells?

induction of apoptosis by DNA damage

which of the following statements regarding the therapeutic index is false?

it is the value of the difference between the maximum effective dose and the minimum effective dose

which one of the following characteristics of cancer cells causes cancers to be lethal?

the ability to metastasize from a primary site to secondary sites and to invade other organs

which one of the following concepts correctly describes what Knudson’s two-hit hypothesis explains?

the mechanism behind hereditary conditions that predispose individuals to an increase risk of cancer

which one of the following statements is false?

there are approximately 10 types of cancer

which one of the following statements correctly describes an oncogene?

a mutated gene whose protein product is produced in increased quantities or has increased activity and contributes to carcinogenesis

what is the relevance of the human genome product to cancer biology?

it provided the basis for whole genomic sequencing of individual tumors and genome wide association studies

Although most cancers result from the accumulation of mutations over time, evidence suggests that a single catastrophic event may account for a small number of cancers. Which statement below is false?

Evidence for this event includes the identification of a characteristic translocation between two particular chromosomes in a cancer cell.

Which of the following intermediates is not formed during radiolysis?

water

Which one of the following statements is true?

The depth of transmission of UV light is dependent on the wavelength.

What unit is used to indicate the amount of biological damage by radiation?

sieverts

Which one of the following pairs of a class of chemical carcinogen and a corresponding

example is not correct?

Polyphenol: epigallocatechin-3-gallate (EGCG).

Which one of the following cancer drugs mimics an endogenous metabolite and interferes with nucleic acid synthesis?

Methotrexate.

Which of the following DNA repair mechanisms are incorrectly matched to the type of damage they repair?

Nucleotide excision repair: replication errors that have escaped editing by polymerases.

UV from the sun is carcinogenic and is the principal cause of skin cancer. Which type of UV light is the most effective carcinogen and what is the most common UV photoproduct?

UVB and cyclobutane pyrimidine dimers.

Which of the following statements about kataegis is false?

It may be caused by the shattering of a chromosome or chromosomes due to radiation.

Which statement about “synthetic lethal” combinations is false?

Poly (ADP-ribose) polymerase (PARP) inhibitors block a pathway involved in breast cell proliferation and can be used to treat breast cancer.

Which experimental method is not used to study transcription factor binding?

Sodium bisulphate treatment and methylation specific PCR

Which one of the following is false?

Hypermethylation of promoter regions activates gene expression.

Which of the following therapeutic strategies is incorrectly matched to a drug for cancer treatment?

HAT (histoine acetyltransferase) inhibitors: SAHA (vorinostat)

Which one of the following statements is false?

AP-1 is made of one component from either the Jun family or the Fos family.

Which one of the following enzymes is not associated with epigenetic carcinogenesis?

DNA polymerase

Which statement below about is false?

Telomeres induce mechanisms that repair DNA double-strand breaks.

Which one of the following statements is false?

Telomerase activity is decreased in 90% of tumors.

The majority of cancer-related single nucleotide polymorphisms are located in:

Intergenic (between genes) and introns of the genome

What is the role of histone acetyltransferases (HATs) in epigenetic regulation of transcription?

They add acetyl groups to histones and relax chromatin folding.

Which statement about microRNAs (miRNAs) is false?

They hybridize to the 5’ end of a specific mRNA and block the initiation of translation.

Which of the following is not a mechanism for termination of tyrosine kinase activity of EGFR?

Inhibition of receptor endocytosis and degradation.

Which one of the following is the molecular target of the therapeutic drug, Herceptin?

The extracellular domain of ErbB2

Which one of the following statements is false?

MAPKs function only in the cytoplasm

Which of the following therapeutic drugs target Raf tyrosine kinase activity?

Nexavar and Zelboraf

Which of the following statements is false, regarding the chronological sequence of events of the EGF signal transduction pathway?

…- SOS → RAS-GTP → RAS-GDP→ RAF → MEK …

Which one of the following statements is false?

Patients with KRAS mutations respond to Erbitux, a monoclonal antibody that targets EGFR.

Which one of the following statements is false?

Raf is activated by the kinsae activity of RAS.

Which one of the following statements is true?

Oncogenic activation of receptor tyrosine kinases may occur through specific mutations that lead to constitutive tyrosine activation.

Which one of the following statements about pharmacogenomics is true?

It is the study of the influence of the genome on an individual’s response to a drug.

Which of the following cancer drugs is not classified as a small molecule tyrosine kinase inhibitor?

Erbitux (cetuximab)

In relation to interacting transcription factors, which one of the following statements is false?

Upon interaction with Myc, MAX down regulates tumor growth and suppresses oncogene regulation.

The cyclin D-cdk4 complex phosphorylates C-terminal residues of pRB upon growth factor stimulation. Which one of the following events does this lead to?

The cyclin E gene is expressed upon release of HDAC from pRB.

The G1 checkpoint leads to which one of the following?

The arrest of the cell cycle in response to DNA damage to prevent its replication.

Which one of the following statements concerning the retinoblastoma protein (pRB) is false?

pRB phosphorylation is carried out in a single step reaction.

Which one of the following statements is false?

The pairing of cyclins to cdks is non-specific.

Which statement about the mechanisms of pRB action is true?

HDAC binds to the B-chain of pRB by an LXCXE motif.

What was the first cdk inhibitor to be tested in clinical trials?

Flavopiridol.

Which one of the following statements is false?

Experimental evidence suggests Cyclin D is a tumor suppressor gene.

Which one of the following statements about aneuploidy is false?

It may be caused by defects in apoptosis.

Which statement regarding Aurora kinases is true?

Aurora kinases are involved in many aspects of mitosis and chromosomal segregation,including regulation of the spindle

All of the following drugs interfere with microtubule and spindle formation except:

Tamoxifen.