ERBB2 and breast cancer: Although the findings of Bates et al. nicely fit our data, it is clear that PLC-γ1 is predominantly activated by RTKs in many cell types [44, 49, 50, 59, 65], particularly by EGFR homodimers and EGFR/HER2 heterodimers in MDA-NEO and MDA-HER2 breast cancer cells [3, 9, 12, 32, 52].