Chapter 1 Questions

d. Induction of cell death and tumor-promoting inflammation..

(Evasion (and NOT induction) of cell death is a hallmark of cancer.

Tumor-promoting inflammation is an enabling characteristic, not a hallmark of cancer)

a. Growth signal autonomy and angiogenesis.
b. Reprogamming energy metabolism and invasion and metastasis.

c. Evasion of growth inhibitory signals and avoiding immune destruction.

d. Induction of cell death and tumor-promoting inflammation.

c. They cannot grow in low serum.

Correct., This is false – they can grow in low serum.

a. Incorrect. This is true – they are not flat and extended.

b. Incorrect. This is true – they can grow without attaching to a substrate.

c. Incorrect., This is true – they fail to exhibit contact inhibition.

Which one of the following statements regarding the phenotype of transformed cells is

false?

a. They adopt a round morphology.

b. They exhibit anchorage independence.

c. They cannot grow in low serum.

d. They grow as foci against a monolayer of normal cells.

b. People are living longer

Correct. Cancer is, most often, a multi-step process. Living longer means that we

are exposed to more carcinogens and there is increased time for mutations to accumulate.

a. Incorrect. The reason is that people are living longer.

c. Incorrect. The genes involved in cancer do not confer a survival advantage.

d. Incorrect. Although some cancers are due to long-term infection by specific

agents, most are not.

Which one of the following statements correctly describes why there has been an

increase in the number of cases of cancer in recent years?

a. People are making fewer visits to their doctors.

b. People are living longer.

c. The genes for cancer confer an advantage of survival and are being selected for during the evolution of the species.

d. The growth in the population and migration has enabled cancer to spread.

c. Phase III

a. Incorrect. Phase I trials examine dose responses for assessing drug safety. This

phase also obtains necessary parameters of the metabolism of the drug in humans.

b. Incorrect. Phase II trials examine the efficacy of the drug in question only.

d. Incorrect. A drug’s effectiveness and efficacy must be demonstrated before a drug

is approved

What phase of clinical trials of a new cancer drug examines a drug’s effectiveness and

compares its efficacy to conventional treatments?

a. Phase I

b. Phase II

c. Phase III

d. After approval of the drug.

c. Induction of apoptosis by DNA damage.

a. Incorrect. Cytostatic drugs inhibit tumor growth.

b. Incorrect. Most cytotoxic drugs do not use these mechanisms.

d. Poisoning of the mitochondria to reduce cell metabolism.

Which one of the following statements describes the effect of most cytotoxic

chemotherapies upon cancer cells?

a. Cessation of DNA replication.

b. Inhibition of translation and tumor suppressor production.

c. Induction of apoptosis by DNA damage.

d. Poisoning of the mitochondria to reduce cell metabolism.

d. It is the value of the difference between the maximum effective dose and the minimum tolerated dose

Correct. This is an incorrect definition. The correct definition is: It is the value of

the difference between the minimum effective dose and the maximum tolerated dose.

a. Incorrect. This is the definition of therapeutic index.

b. Incorrect. This is true.

c. Incorrect. This is true.

Which of the following statements regarding the “therapeutic index” is false?

a. It is the value of the difference between the minimum effective dose and the maximum

tolerated dose.

b. The larger the value, the safer the drug.

c. The therapeutic index for most chemotherapies is small compared to aspirin.

d. It is the value of the difference between the maximum effective dose and the minimum

tolerated dose

d. The ability to metastasize from a primary site to secondary sites and to invade other organs.

Correct. Metastasis poses a difficult clinical problem: cancer cells compete with

normal cells for oxygen and nutrients and can physically obstruct the function of organs.

a. Incorrect. This does not result in lethality.

b. Incorrect. This answer does not address the physiology of the patient.

c. Incorrect. Cancer cells activate angiogenesis.

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

a. The ability of cancer cells to change shape.

b. The ability to grow in low serum.
c. The ability to inhibit angiogenesis.

d. The ability to metastasize from a primary site to secondary sites and to invade other

organs.

c. The mechanism behind hereditary conditions that predispose individuals to an increased

risk of cancer.

correct. The “two- hit” hypothesis states that both alleles of a tumor suppressor

gene need to be mutated to trigger carcinogenesis and that a germline mutation in one allele

of a tumor suppressor results in a condition of an increased risk of cancer.

a. Incorrect. Oncogenes do result from mutated normal genes called proto- oncogenes, but the two-hit hypothesis does not explain this.ncorrect. Oncogenes do result from mutated normal genes called proto- oncogenes, but the two-hit hypothesis does not explain this.

b. Incorrect. This explains that a single cell containing mutations is all that is needed

for the development of cancer. The two-hit hypothesis does not explain this.

d. Incorrect. Haploinsufficiency explains an alternative mechanism for tumor

suppressor genes where one mutated allele leads to genetic instability.

Which one of the following concepts correctly describes what Knudson’s two-hit

hypothesis explains?

a. Proto-oncogenes can be mutated to become oncogenes.

b. The development of cancer is clonal.

c. The mechanism behind hereditary conditions that predispose individuals to an increased

risk of cancer.

d. Haploinsufficiency.

b. There are approximately ten types of cancer.

Correct. This is false. Over 100 types of cancer have been classified and subsets

are still being defined

a. Incorrect. This is true. Skin cancer is different from liver cancer.

c. Incorrect. This is true. A benign tumor does not constitute cancer.

d. Incorrect. This is true, because cancers of different origins have distinct features.

Which one of the following statements is false?

a. Cancer is considered as a group of diseases.

b. There are approximately ten types of cancer.

c. Cancer is diagnosed by the presence of a malignant tumor.

d. A cancer is described according to its cell of origin.

b. A mutated gene whose protein product is produced in increased quantities or has

increased activity and contributes to carcinogenesis

Correct. It acts in a dominant manner to initiate tumor formation.

a. Incorrect. This is a tumor suppressor gene.

c. Incorrect. An oncogene is a mutated gene and can cause of cancer.

d. Incorrect. An oncogene is produced in increased quantities or has increased

activity.

Which one of the following statements correctly describes an oncogene?

a. A gene that codes for a protein that helps inhibit tumor growth and formation.

b. A mutated gene whose protein product is produced in increased quantities or has

increased activity and contributes to carcinogenesis.

c. A type of cancer therapy.

d. A mutated gene whose protein product is produced in deficient quantities and contributes

to carcinogenesis

c. It provided the basis for whole-genomic sequencing of individual tumors and genome-wide association studies.

Correct. Work by Puente et al. (2011) and Wolpin et al. (2014) are examples. The

International Cancer Genome Consortium has been organized to characterize and sequence

several hundreds of tumors for 50 types of cancer.

a. Incorrect. The genomic profile of an individual’s tumor is unique and “personal”.

b. Incorrect. Next generation sequencing has been developed since The Human

Genome Project and has greatly advanced the speed at which genomes can be sequenced

d. Incorrect. This knowledge is not available.

What is the relevance of the Human Genome Project to cancer biology?

a. We now understand that the genomic profile of an individual’s tumor is not unique to that

patient but shared among all those with that type of cancer.

b. It has used technologies that are so efficient it will be a long time before improvements are

made.

c. It provided the basis for whole-genomic sequencing of individual tumors and genome-wide

association studies.

d. The completion of the Human Genome Project has allowed us to know who will get cancer

later in life.