Cancer Pharmacology - Antimetabolites Flashcards
Are Antimetabolites cell cycle specific?
YES
Antimetabolites are cell cycle specific. Which phase do they work in?
S phase
Antimetabolites are cell cycle specific. Which phase do they work in?
S phase
What are Antimetabolites?
Structural analogs to compounds necessary for cell proliferation
– Block or subvert cell replication
What is a Folic Acid Analog?
Methotrexate
What is a Folic Acid Analog?
Methotrexate
MOA for Methotrexate?
(-) dihydrofolate reductase
= folic acid will not be converted to tetrahydrofolic acid
At low doses, what can Methotrexate treat?
RA and Psoriasis
At higher doses, what does Methotrexate do?
Causes injury to healthy tissues
At higher doses, Methotrexate causes injury to healthy tissues. What can prevent this?
Leucovorin
At higher doses, Methotrexate causes injury to healthy tissues. What can prevent this?
Leucovorin
What does Leucovorin do?
Allows thymidine synthesis to proceed
Leucovorin spares the patient what symptoms?
GI and bone marrow toxicity
What is a Pyrimidine Analog?
Fluorouracil
What is Pyrimidine Analog?
Fluorouracil
MOA for Fluorouracil?
Binds and (-) thymidylate synthetase = No DNA synthesis
Fluorouracil is pro-drug. What does it converted to?
5-FU –> FdUMP
Adverse effects of Fluorouracil?
Anorexia, nausea, diarrhea, stomatitis
Adverse effects of Fluorouracil?
Anorexia, nausea, diarrhea, stomatitis
What is a Purine Analog?
Mercaptopurine (6-MP)
What is a Purine Analog?
Mercaptopurine (6-MP)
MOA for Mercaptopurine?
(-) purine nucleotide synthesis by incorporating triphosphate
During Mercaptopurine’s biotransformation, it gets inactivated by?
Xanthine oxidase
Mercaptopurine’s effects can be diminished by xanthine oxidase. What can be added to therapy to prevent this?
A Xanthine oxidase inhibitor = Allopurinol!
Mercaptopurine’s effects can be diminished by xanthine oxidase. What can be added to therapy to prevent this?
A Xanthine oxidase inhibitor = Allopurinol!
