B / 29 : Drugs used in cancer treatment I (antimetabolites)

Question 1

What are cytotoxic and cytostatic agents?

Answer 1

• Cytotoxic : act on cell proliferation - kills cells
• Cytostatic : act on cellular systems of proliferation - just stops growth

Question 2

What are antimetabolites?

Answer 2

Molecules that interfere with the availability of normal purine or pyrimidine nucleotide precursors by inhibiting their synthesis or competing with them

Question 3

When do metabolites have the biggest effect?

Answer 3

During the S-phase

Question 4

What are the types of antimetabolites?

Answer 4

• Folate antimetabolites
• Pyrimidine antimetabolites
• Purine antimetabolites

Question 5

What are the 2 folate antimetabolites?

Answer 5

• Methotrexate
• Pemetrexed

Question 6

Methotrexate
- MOA
- Effect
- Indication
- SE
- ROA

Answer 6

• Folate antimetabolite
• Inhibits dihydrofolate reductase : decreased purine and thymidine synthesis
• For breast, ovarian, stomach, colon cancer + CNS lymphoma, osteosarcoma
• BM suppression, alopecia, GI disturbances
• Oral, parenteral

Question 7

Pemetrexed
- MOA
- Indication
- SE

Answer 7

• Folate antimetabolite
• For non-small cell lung carcinoma, mesothelioma
• BM suppression, nausea, vomiting, hand foot syndrome

Question 8

What are 3 examples of pyrimidine antimetabolites?

Answer 8

• 5-fluorouracil
• Capecitabine
• Cytarabine

Question 9

5-fluorouracil
- MOA
- Effect
- Indication
- SE
- ROA

Answer 9

• Pyrimidine antimetabolite
• Inhibition of DNA synthesis
• For colorectal cancer
• BM suppression, alopecia, GI disturbances, hand-foot syndrome
• IV

Question 10

Capecitabine
- MOA
- Effect
- Indication
- SE
- ROA

Answer 10

• Pyrimidine antimetabolite
• Inhibition of DNA synthesis
• Metastatic breast cancer, colon cancer
• BM suppression, alopecia, GI, hand foot syndrome
• Oral

Question 11

Cytarabine
- MOA
- Effect
- Indication
- SE

Answer 11

• Pyrimidine antimetabolite
• converted to ara-CTP : inhibition of both DNA and RNA synthesis + inhibition of DNA polymerase
• AML, non-hodgkin lymphoma
• BM suppression, GI, hepatotoxic

Question 12

What is an example of a purine antimetabolite?

Answer 12

6-merkaptopurine

Question 13

6-merkaptopurine
- MOA
- Effect
- Indication
- SE

Answer 13

• Purine antimetabolite
• Inhibits enzymes involved in purine metabolism
• For acute leukemia in children
• BM suppression, GI disturbances, anorexia