Immunoblotting Analysis of Cellular Signaling

Whole cell lysates were prepared for immunoblotting as described previously [32 (link), 33 (link)]. Specific primary antibodies against PARP, Caspase 3, MCL1, XIAP, p-STAT3(Tyr705), STAT3, p-STAT1(Tyr701), STAT1, p-STAT5(Tyr694), STAT5, JAK2, p-Src(Ser17), c-Src, p-P38(Thr180/Tyr182), P38, p-ERK1/2(Thr202/Tyr204), ERK1/2, p-mTOR(Ser2448) and mTOR were purchased from Cell Signaling Technology (Danvers, MA); a specific primary antibody against p-JAK2(Tyr1007/Tyr1008) was purchased from Santa Cruz Biotechnology, Inc. (Santa Cruz, CA); anti-Flag and anti-Myc antibodies were purchased from Medical & Biological Laboratories (Tokyo, Japan). GAPDH and β-actin were purchased from Abgent (Suzhou, China). Anti–mouse immunoglobulin G (IgG) and anti–rabbit IgG horseradish peroxidase conjugated antibody were purchased from R&D Systems (Minneapolis, MN).