Lecture 4: Oncogenic Viruses

Question 1

Oncogenic RNA viruses tend to induce cancer by…

Answer 1

Transmitting an oncogene.

Question 2

Oncogenic DNA viruses tend to induce cancer by…

Answer 2

T-antigen or equivalent. (SV40, adenovirus, papillomavirus)

Affecting the cell cycle; inactivating tumor suppressor proteins. Especially p53 and RB.

Question 3

What cancer does human T-cell leukemia virus cause?

Answer 3

Leukemias/lymphomas

HTLV-1 integrates, reduces expression of Tax, but HBZ persists.

Question 4

What cancer does papillomavirus cause?

Answer 4

Cervical cancer (and warts)
E6 binds p53
E7 binds Rb, prevent interaction with E2F
E2 expression inhibits ^, but is reduced on viral integration.

Question 5

What cancer does Epstein-Barr virus cause?

Where is it prevalent?

Answer 5

Burkitt’s Lymphoma: Africa
Naso-pharyngeal cancer: South China, Vietnam, Arctic Eskimos

(mononucleosis)

Question 6

What cancer can Hepatitis B cause?

Where is it prevalent?

Answer 6

Hepatocellular cancer. Vaccine present

Asia, Africa

Question 7

What cancer does HHV8 cause?

Where is it prevalent?

Answer 7

Kaposi’s Sarcoma

Africa.