Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
10 Cards in this Set
- Front
- Back
|
Antimetabolties are CCS or CCNS?
|
CCS - target S phase
|
|
|
Methotrexate mechanism of action?
|
dihydrofolate reducatase inhibitor leads to decreased synthesis of thymidylate synthesis, purine nucleotides and amino acids.
|
|
|
Mercaptopurine and thioguanine mechanism of action?
|
Purine antagonists - prodrugs needs HPGRT to activate to cytotoxic form. inhibit denovo purine and pyrimdine synthesis
|
|
|
5-FU mechanism?
|
Pyrimidine antagonist - gets converted to FdUMP which inhibits thymidylate synthase (suicide inhibition)
|
|
|
methotrexate toxicity?
|
Myelosuppression, skin adn GI mucosa toxic reduced by folinic acid (leucovorin rescue). Pulmonary infiltrates.
|
|
|
leucovarin rescue with mtx?
|
Rescue with mtx - leucovorin needs to be actively tranported into cells to reduce mtx cytotoxicity. normal cells can transport it and cancer cells cannot.
|
|
|
Resistance to mercaptopurine?
|
Loss of HGPRT
|
|
|
Mercaptopurine toxicity?
|
Myelosuppression, cholestasis, pancreatitis, oral/GI ulcers. Allopurinol decreses tox. mostly well tolerated.
|
|
|
methotrexate resistance/
|
DHFR mutations and decreased polyglutamate formation
|
|
|
leucovorin and 5-FU/
|
enhances formation of ternary complex and thus efficacy of 5-FU. leads to increased toxicity in non-cancerous tissue.
|
