Fig. 6

Effects of insulin on heregulin-1ß/HER3 signalling in HCC cell lines. a Hep3B cells were treated with insulin (left: increasing doses during 10 min; right: 10⁻⁸ M for different times) or with heregulin-1ß (HRG-1ß increasing doses during 10 min). Whole-cell lysates (20 µg) were analysed by Western blot for phosphorylation and expression of HER3, IR and/or AKT. b Hep3B cells were transiently transfected with a control (siCont) or siRNA directed against IR (siIR) and then treated with or without 10⁻⁸ M insulin for 10 min. Whole-cell lysates (20 μg) were analysed by Western blot for phosphorylation and expression of HER3 and/or IR. c Hep3B cells were treated or not with 2 uM gefitinib (left) or transiently transfected with control (siCont) or siRNA directed against EGFR (siEGFR) (right) and then treated with or without 10⁻⁸ M insulin for 10 min. Whole-cell lysates (20 µg) were analysed by Western blot for phosphorylation and expression of HER3, EGFR and/or IR. d Hep3B (left) and Huh7 (right) cells were transiently transfected with a control (siCont) or siRNA directed against IR (siIR) an then treated with or without increasing doses of heregulin-1ß for 10 min. Whole-cell lysates (20 µg) were analysed by Western blot for phosphorylation and expression of HER3, AKT and/or IR