Question 1

Which of the following best describes the difference between solid cancers and blood cancers (hematological malignancies)?

Accepted Answer

Solid cancers start in organs or tissues and form tumors, while blood cancers start in bone marrow or immune system and spread through blood and lymph without forming solid tumors.

Question 2

Which mechanism is NOT considered a hallmark of cancer development?

Accepted Answer

Enhanced photosynthesis

Question 3

A patient is found to have a gain-of-function mutation in a proto-oncogene. What is the most likely consequence of this mutation?

Accepted Answer

Uncontrolled cell proliferation due to oncogene activation

Question 4

According to Knudson’s Two-Hit Hypothesis, what is required for a tumor suppressor gene to lose its function and contribute to cancer?

Accepted Answer

Both alleles of the gene must be inactivated by mutations

Question 5

Which gene is known as the 'guardian of the genome' and is commonly mutated in many cancers, leading to defective DNA damage response and apoptosis?

Accepted Answer

TP53

Question 6

A genetic test reports a mutation as 123A\u003eT. What does this notation mean?

Accepted Answer

A substitution of adenine (A) with thymine (T) at the 123rd position of the coding DNA sequence

Question 7

Which of the following statements about somatic and germline mutations is correct?

Accepted Answer

Germline mutations are inherited and present in all cells, while somatic mutations occur after birth and are not passed to offspring.

Question 8

Which of the following is an example of a hereditary cancer syndrome caused by a germline mutation?

Accepted Answer

Familial adenomatous polyposis (FAP) due to APC gene mutation

Question 9

What is the role of apoptosis in normal cells, and how is it altered in cancer cells?

Accepted Answer

Apoptosis is a process of programmed cell death that removes damaged cells; in cancer cells, apoptosis is often evaded, allowing survival of abnormal cells.

Question 10

Which of the following best explains the concept of 'driver mutations' in cancer genetics?

Accepted Answer

Mutations that provide a growth advantage to tumor cells and contribute directly to cancer development

Question 11

A patient with retinoblastoma is found to have inherited one mutated RB1 allele. According to the Two-Hit Hypothesis, what must occur for the cancer to develop?

Accepted Answer

A second mutation must occur in the remaining normal RB1 allele in a somatic cell

Question 12

Which of the following is a common mechanism by which oncogenes are activated in cancer cells?

Accepted Answer

Gene amplification, such as HER2 in breast cancer

Question 13

If a tumor biopsy reveals thousands of somatic mutations, but only a few contribute to the cancer phenotype, what are the remaining mutations called?

Accepted Answer

Passenger mutations

Question 14

Which equation best represents the probability $$P$$ that both alleles of a tumor suppressor gene are inactivated, given the mutation rate per allele is $$\mu$$?

Accepted Answer

$$P = \mu^2$

Question 15

A patient’s genetic test for hereditary cancer risk is negative. What does this result most likely indicate?

Accepted Answer

The patient does not carry the tested germline mutations, but may still develop cancer due to somatic mutations

Question 16

Which of the following best describes the function of tumor suppressor genes?

Accepted Answer

They inhibit cell growth and division, preventing tumor formation

Question 17

In a family with Lynch Syndrome, which gene is most likely mutated, and what type of inheritance does this syndrome follow?

Accepted Answer

MLH1 or MSH2; autosomal dominant inheritance

Question 18

Which of the following is a real-world example of gene amplification in cancer?

Accepted Answer

Amplification of HER2 gene in breast cancer

Question 19

Which process allows cancer cells to survive and proliferate despite severe DNA damage?

Accepted Answer

Evasion of apoptosis

Question 20

A tumor is found to have double minute chromosomes containing amplified MYCN and MDM2 genes. What is the significance of this finding?

Accepted Answer

It suggests aggressive tumor growth due to oncogene amplification

Cancer Genetics: Mechanisms and Genetic Basis

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