Prevent DNA synthesis / Inhibitors of DNA synthesizing enzymes / Cytarabine
II. INHIBITORS OF DNA SYNTHESIZING ENZYMES
A. Antimetabolites
Mechanisms of Action
CYTARABINE
(arabinose analog of cytidine; also called cytosine arabinoside, AraC)
- pyrimidine analogue that is activated by conversion to AraCTP
- phosphorylated and competes with dCTP for incorporation into DNA
- once inserted into DNA, CYTARABINE blocks DNA elongation by inhibiting DNA polymerase
- also causes reiteration of DNA segments, increasing the probability of mutations
- induces terminal differentiation of leukemic cells