Folate and B12 Inhibitors--Fitz Flashcards
Folate donates ___________ to pyrimidine/purine synthesis
carbons, both pyrimidine and purine synthesis
Leucovorin is used in _________ therapy to allow normal cells with ___________ to get adequate amounts of ________
rescue therapy
normal reduced folate carrier
folate
2 carriers of folate into cells:
reduced folate carrier
folate transporter
This is the most important folate mover in physiologically normal cells
folate receptor
This is the most important folate mover in neoplastic cells
reduced folate carrier
This receptor is usually overexpressed in cancerous cells, leading to differential sensitivity of cancerous tissue to methotrexate
reduced folate carrier
This receptor is usually underexpressed in cancerous cells, making it a difficult way to get folate into a cell
reduced folate transporter
This process keeps folate in cells
polyglutamination
Why is folate supplementation in commercial products a bad idea?
it covers B12 deficiency by hiding megaloblastic anemia and therefore ensuing neurological disease (subacute combined degeneration of spinal cord)–but protects against other folate-deficiency diseases. what are you gonna do.
How do purine analogs inhibit the purine salvage pathway?
inhibit GPAT because of GMP buildup
This drug has a total lifetime cap on lifetime limit?
doxorubicin
Why is there a lifetime cap on doxorubicin?
chronic use can lead to CHF
What is the rate-limiting step in DNA synthesis?
thymidylate synthase
This antineoplastic has the most marrow therapeutic index
5-FU
This increases in B12 deficiency
homocysteine