Fig. 2
From: Lack of interaction between ErbB2 and insulin receptor substrate signaling in breast cancer
Modulation of IRS1 and IRS2 levels in ErbB2 expressing mouse cells alters ErbB2 signaling but not cell growth. a BRI-JM04 mouse cells were starved overnight and then treated in the morning with either 60 ng/ul of heregulin (HRG) or 20 ng/ul of IGF1 for 15 mins and then harvested. Expression of ErbB2 signaling proteins was determined by immunoblotting. Blots are representative of 3 experiments. b BRI-JM04 cells were transfected with siRNA against IRS1, IRS2, or both IRS1 and IRS2. At 48 h post-transfection, cells were stimulated with 20 ng/ul heregulin (H) or 60 ng/ul EGF (E) for 15 min. Cells were then harvested and analyzed for ErbB2 signaling by immunoblotting. c After IRS1 or IRS2 knockdown, BRI-JMO4 cells were plated and maintained with or without serum for 4 days. Cell growth was determined by CyQuant. Graph is representative of 3 experiments. One-way Anova was applied. N.S. = not significant