Cytosine arabinoside in the treatment of T-cell acute lymphoblastic leukemia.

Abstract

The place of cytosine arabinoside (araC) in the treatment of T-cell acute lymphoblastic leukemia was studied by measuring nucleoside transport sites and the conversion of araC to its triphosphate (araCTP) in lymphoblasts from the peripheral blood of two patients, who were then treated with araC. Equilibrium binding of 3H-nitrobenzylmercaptopurine riboside (3H-NBMPR), a specific ligand of the nucleoside transporter, gave 16,510 to 29,400 sites/cell for T-lymphoblasts on presentation or early in relapse compared with 2730 +/- 1570 sites/cell for non-T-lymphoblasts. Accumulation of araCTP from 1 microM araC was four times greater in T-cell than non-T-cell lymphoblasts. One patient was treated w..