STI 571 inhibits SLF-dependent proliferation of M-07e cells.

Serum was withheld from M-07e cells overnight before they were used in proliferation assays. Cells were plated in a 96-well plate at a concentration of 50 000 cells/well and grown in RPMI-1640 supplemented with 10% fetal-calf serum (FCS) with and without 200 ng/mL SLF. STI 571 was added at the same time as SLF. Proliferation at 48 hours was measured with an XTT-based assay system. Results are expressed as the percentage of maximal proliferation (SLF only) (± SD). Representative results from 1 of 6 independent experiments are shown.