Effects of FGFR1 siRNA on the KG-1 cell line. (A) siRNA-induced silencing of FGFR1 was assessed by immunoblots of whole-cell lysates 48 hours after siRNA transfection. Down-regulation of the FGFR1OP2-FGFR1 fusion resulted in decreased phosphorylation of STAT5, STAT3, ERK, Shc, PLC-γ1, PLCγ2, and SHIP1. NP and FGFR1 indicate siControl nontargeting siRNA pool and FGFR1 SMARTpool siRNA, respectively. (B) Electroporation with FGFR1 siRNA into KG-1 cells resulted in a decrease of proliferation. Mean value plus SD of experiments performed in duplicate is represented. (C) Induction of apoptosis. Percentage of total population is indicated.