Exam 1- Antimetabolites/Alkylating agents/Platinum Flashcards
What phase of the cell cycle do antimetabolites primarily work in?
S phase
Pyrimidine analogs
5-fluorouracil, capecitabine (uracil)
Cytarabine, gemcitabine (cytosine)
Purine analogs
6-mercaptopurine
Why is allopurinol contraindicated in patients taking 6-mercaptopurine?
Allopurinol is a xanthine oxidase inhibitor, which is the enzyme that breaks down 6-mercaptopurine
What is the MOA of cytarabine?
competitively inhibits DNA polymerase and also incorporates into DNA to further inhibit DNA synthesis
Are alkylating agents considered cell-cycle specific or non-cell cycle specific?
NON cell-cycle specific
What is the most commonly used alkylating agent?
cyclophosphamide
Which alkylating agent has more modest side effects than others?
cyclophosphamide
Why does cyclophosphamide have only mild bone marrow toxicity?
high levels of aldehyde dehydrogenase in bone marrow, the enzyme that inactivates it
Since cyclophosphamide is a prodrug, it requires _______________ by _____________
hydroxylation by cytochrome P450
What is mesna used for?
mesna is used to inactivate acrolein metabolites (from cyclophosphamide) in the bladder
Mitomycin C has _________ myelosuppression than cyclophosphamide
higher
Why does cisplatin form intrastrand crosslinks, as opposed to interstrand?
The bond lengths and angles from cisplatin’s cis geometry
Cisplatin has dose-limiting __________________
nephrotoxicity