Cytotoxic Agents

Question 1

name alkylating agents

Answer 1

• cyclophosphamide

Question 2

what is the mechanism of action of cyclophosphamide?

Answer 2

• alkylating agent
• causes cross-linking in DNA

Question 3

what are the adverse effects of cyclophosphamide?

Answer 3

• haemorrhagic cystitis
• myelosuppression
• transitional cell carcinoma

Question 4

name cytotoxic antibiotics

Answer 4

• bleomycin
• anthracyclines (e.g. doxorubicin)

Question 5

what is the mechanism of action of bleomycin?

Answer 5

degrades preformed DNA

Question 6

what is the adverse effect of bleomycin?

Answer 6

• lung fibrosis

Question 7

what is the mechanism of action of anthracyclines?

e.g. doxorubicin

Answer 7

stabilises DNA-topoisomerase II complex inhibits DNA and RNA synthesis

Question 8

what is the adverse effect of anthracyclines?

e.g. doxorubicin

Answer 8

cardiomyopathy

Question 9

name antimetabolites

Answer 9

• methotrexate
• fluorouracil (5-FU)
• 6-mercaptopurine
• cytarabine

Question 10

what is the mechanism of action of methotrexate?

Answer 10

inhibits dihydrofolate reductase and thymidylate synthesis

Question 11

what are the adverse effects of methotrexate?

Answer 11

• myelosuppression
• mucositis
• liver fibrosis
• lung fibrosis

Question 12

what is the mechanism of action of fluorouracil?

Answer 12

pyrimidine analogue inducing cell cycle arrest and apoptosis by blocking thymidylate synthase

Question 13

what are the adverse effects of fluorouracil?

Answer 13

• myelosuppresion
• mucositis
• dermatitis

Question 14

what is the mechanism of action of 6-mercaptopurine?

Answer 14

purine analogue that is activated by HGPRTase, decreasing purine synthesis

Question 15

what is the adverse effect of 6-mercaptopurine?

Answer 15

myelosuppression

Question 16

what is the mechanism of action of cytarabine?

Answer 16

• pyrimidine antagonist
• interferes with DNA synthesis and inhibits DNA polymerase

Question 17

what are the adverse effects of cytarabine?

Answer 17

• myelosuppression
• ataxia

Question 18

name drugs which act on microtubules

Answer 18

• vincristine, vinblastine
• docetaxel

Question 19

what is the mechanism of action of vincristine and vinbalstine?

Answer 19

inhibits formation of microtubules

Question 20

what are the adverse effects of vincristine?

Answer 20

• peripheral neuropathy (reversible)
• paralytic ileus

Question 21

what is the adverse effect of vinblastine?

Answer 21

myelosuppression

Question 22

what is the mechanism of action of docetaxel?

Answer 22

prevents microtubule depolymerisation and disassembly, decreasing free tubulin

Question 23

what is the adverse effect of docetaxel?

Answer 23

neutropenia

Question 24

name topoisomerase inhibitors

Answer 24

• irinotecan

Question 25

what is the mechanism of action of irinotecan?

Answer 25

inhibtis topoisomerase I which prevents relaxation of supercoiled DNA

Question 26

what is the adverse effect of irinotecan?

Answer 26

myelosuppression

Question 27

what is the mechanism of action of cisplatin?

Answer 27

causes cross-linking in DNA

Question 28

what are the adverse effects of cisplatin?

Answer 28

* ototoxicity * peripheral neuropathy * hypomagnesaemia

Question 29

what is the mechanism of action of hydroxyurea (hydroxycarbamide)?

Answer 29

inhibits ribonucleotide reductase, decreasing DNA synthesis

Question 30

what is the adverse effect of hydroxyurea (hydroxycarbamide)?

Answer 30

myelosuppression

Question 31

what is the adverse effect of hydroxyurea (hydroxycarbamide)?

Answer 31

myelosuppression