Health / Medical Topics |
Cytarabine
Pronunciation
Definition 1
A drug used to treat certain types of leukemia and prevent the spread of leukemia to the meninges (three thin layers of tissue that cover and protect the brain and spinal cord). It is also being studied in the treatment of other types of cancer. Cytarabine blocks tumor growth by stopping DNA synthesis. It is a type of antimetabolite. (NCI Dictionary)
Definition 2
An antimetabolite analogue of cytidine with a modified sugar moiety (arabinose instead of ribose). Cytarabine is converted to the triphosphate form within the cell and then competes with cytidine for incorporation into DNA. Because the arabinose sugar sterically hinders the rotation of the molecule within DNA, DNA replication ceases, specifically during the S phase of the cell cycle. This agent also inhibits DNA polymerase, resulting in a decrease in DNA replication and repair. (NCI Thesaurus)