Figure 3

Suppressing JAK/STAT3 signaling enhanced gefitinib-induced apoptosis in human ovarian cancer cells. SKOV3 (A&B) and MDAH2774 (C&D) cells were treated with gefitinib, JAKi, either alone or together, for 48 h. Apoptosis was determined by flow cytometry using Annexin V and PI staining (A&C) or for cleaved poly-ADP ribose polymerase (PARP) and cleaved caspase-3 by Western blot (B&D). **, P < 0.005; ***, P < 0.005, combination vs. JAKi alone or gefitinib alone. (E) SKOV3 cells were transfected with siRNA against STAT3, JAK1, or control siRNA and treated with gefitinib or (F) transfected with siRNA against EGFR and treated with JAKi. After 48 h, cells were harvested and evaluated for apoptosis using Annexin V staining. *, P < 0.05; **, P < 0.005, vs. control siRNA.