MOLECULAR BIOLOGY OF CANCER Question Papers (Supple, 2008)

SET : 1

1. Cell fusion studies indicated the following :

a) Experiment 1 – G1 cells fused with S cells entered into S – Phase.

b) Experiment 2 – G2 cells fused with S cells did not enter into S – Phase.

Provide a correct explanation for the results observed in the two experiments.

2. Name any three DNA viruses that induce cancers.

Discuss the mechanism of induction of cancers.

3. Why Rb gene is called a tumor suppressor gene? Support your answer.

4. Which chemical carcinogens are involved in the induction of skin cancers? Name the source of these carcinogens.

5. Write short notes on any two of the following :

a) UV – A light and the carcinogenic activity.

b) UV – B light and the carcinogenic activity.

c) UV – C light and the carcinogenic.

6. List the food components that could associated with carcinogenic activity.

List the food components that could give protection against carcinogenic activity of other compounds.

7. Compare the two techniques – Biopsy & Papsmear with reference to technical ease, results obtained, tissues to be screened and risk factors. Are they mutually exclusion techniques?

8. What properties of the tumors are considered in planning radiation dose? Why are radiation doses split over a period of time including the daily dose also being fractionated?

SET : 2

1. Rb along with E2F acts as a molecular switch critically regulating gene expression and cell cycle regulation. Describe the mechanism.

2. How does Ras protein control cell cycle? Majority of C – Ras oncogenes obtained from cancerous tissue have mutations in codon 12, 13, 59 or 61 in the coding sequence. Suggest an explanation.

3. Define familial retinob;astoma.

4. What are xenobiotics? Describe the mecganism involved in metabolism of xenobiotics.

5. Discuss in detail the role of DNA repair enzyme in repairing mutagenic damage induced by carcinogenic agents.

6. The American Cancer Society has listed some very common warning signals as cautions. List these signals. Why is it important to check for these signals? Discuss.

7. On what principles does ultrasonography work?

Cancers in which suspected parts of the body are screened by ultrasonography?

8. Name the major conventional therapies for cancer. Summarize the role of each in cancer treatment.

SET : 3

1. Define and differentiate START and Restriction Point.

What are the factors and mechanisms controlling passage of cells through these points?

2. How does Ras protein control cell cycle? Majority of C – Ras oncogenes obtained from cancerous tissue have mutations in codon 12, 13, 59 or 61 in the coding sequence. Suggest an explanation.

3. Why Rb gene is called a tumor suppressor gene? Support your answer.

4. Discuss the role of deletion and duplication in cancer induction.

Taking a specific example, show the mechanism involved in induction of deletion and duplication.

5. What are sunscreens made of and what potential do they pose in terms of cancer induction? What role does P53 gene play in removing UV induced damage in skin?

6. Write short notes on any two of the following :

a) invasion

b) Intravasion

c) Metastatic colonization.

7. Write short notes on the usefulness of the following in cancer diagnosis :

a. anisography

b. isotope Scan

c. ultrasonography

d. mammogram.

8. Describe the 2 main types of radiation treatments, their source and the conditions that are considered for their implantation.

SET : 4

1. Describe the molecular mechanism of CdK regulation. Suppourt your answer with a diagram.

2. Name any 3 oncogenes which function as receptors and the protein encoded by their protooncogene. Discuss the role of one oncogene in inducing cancer.

3. Name the 2 different types of Retinoblastomas. Discuss the genetic basis for each.

4. Describe Ames Test in detail. Which chemicals are subjected to this test?

5. Name the different units that measure radiation energy.

Describe the rate of release of energy and its biological effects.

6. Cancer development is a multistep process. Discuss a specific example to support this concept.

7. Tumors of which part of the body can be diagnosed by endoscopy? Can any other techniques be used for diagnosis of tumor in these parts of the body? Comment.

8. Name the major conventional therapies for cancer. Summarize the role of each in cancer treatment.