Topoisomerase Inhibitors

Question 1

Etoposide

Answer 1

Class: Epipodophyllotoxins

Mechanism of action: Inhibit topoisomerase II causing DNA damage in the form of dsDNA breaks

Therapeutic uses: Testicular, Lung, Non-Hodgkin’s lymphoma

Toxicity: DOSE-LIMITING MYELOSUPPRESSION (NEUTROPENIA)
oral mucositis

Question 2

Teniposide

Answer 2

Class: Epipodophyllotoxins

Mechanism of action: Inhibit topoisomerase II causing DNA damage in the form of dsDNA breaks

Therapeutic uses: ALL

Toxicity: DOSE-LIMITING MYELOSUPPRESSION (NEUTROPENIA)
oral mucositis

Question 3

Irinotecan

Answer 3

Class: Camptothecin Analog

Mechanism of Action: Inhibit topoisomerase I causing DNA damage in the form of ssDNA breaks.

Therapeutic uses: Advanced colorectal primarily, also lung, ovarian, cervical, and brain

Toxicities: Severe neutropenia, severe diarrhea

Question 4

Topotecan

Answer 4

Class: Camptothecin Analog

Mechanism of Action: Inhibit topoisomerase I causing DNA damage in the form of ssDNA breaks.

Therapeutic uses: Ovarian, small cell lung cancer

Toxicities: Severe neutropenia, severe diarrhea