Figure 1. Rapamycin showed antitumor activity and reduced KIT expression in GIST430 and GIST48 cells.

GIST430 and GIST48 cells were treated with rapamycin at the indicated doses (A) and times (B) and analyzed by immunoblotting against phospho- and total KIT, RPS6KB1, MAPK1/3, AKT, or MAP1LC3 proteins. GIST430 and GIST48 cells were incubated with rapamycin at the indicated doses, and IC₅₀ was determined by the cell viability assay (C) and clonogenic assay (D). GIST430 and GIST48 cells were treated with 40 μM rapamycin from 12 to 48 h and then analyzed by Annexin V staining (E) or immunoblotting against PARP1 (F). All experiments were repeated at least three times. The data are expressed as the mean ± S.E. of two or more independent experiments.