Question

answer to:

a) How do viruses contribute to cancer? Use 2 examples of different viruses in your answer.

b) Some cancers are consistently associated with the deletion of a particular part of a chromosome. Does the deleted region contain an oncogene or a tumor-suppressor gene? Explain

Answer 1

a. Yes, viruses are known to cause cancer. The Human Papilloma Viruses (HPVs) are konwn to cause cervical cancer. Human Immunodeficiency Virus (HIV) is known to give rise to cancer and especially linked to central nervous system lymphomas.

b. The deleted gene consists of tumor-suppressor gene which inhibits cell proliferation. Deletion of a particular part of a chromosome which may contain the tumor-suppressor gene will cause the rapid proliferation of cells resulting in cancer. Oncogene facilitates cell division and their abnormal increase and thus their deletion in a chromosome will not result in cancer.