The role of nucleoside/nucleotide transport and metabolism in the uptake and retention of 3′-fluoro-3′-deoxythymidine in human B-lymphoblast cells

Initial rates of FLT uptake were a function of both concentrative and equilibrative transporters. TK1 activity was an absolute requirement for the accumulation of FLT. Retention was dependent on nucleoside/nucleotide efflux and retrograde metabolism of FLT nucleotides.