The expression of FLT3-ITD-TKD dual mutants induces hyperactivation of STAT5 and up-regulation of Bcl-x(L) and RAD51. (A) The phosphorylation status of STAT5 in extracts of Ba/F3 FLT3WT, FLT3-ITD, and FLT3-ITD-D835Y/N cells was determined by Western blot analysis using the polyclonal anti-pSTAT5 antibody. The membrane was stripped and reproved with polyclonal anti-STAT5 antibody. Expression of Bcl-x(L) and RAD51 in the same lysates was analyzed by immunoblotting with monoclonal anti–Bcl-x(L) (B) and polyclonal anti-RAD51 (C) antibodies. Identical protein loading in all lanes was confirmed by immunoblotting using an anti–β-actin antibody.