A-B. Relative mRNA level of HER2 in MCF-7 and MCF-7R cells transfected with Beclin 1 siRNA or control siRNA in the presence of tamoxifen was determined by real time qPCR. β-actin gene was used as an endogenous control for normalization. Results showed were means ± S.D. of three independent reactions. **p < 0.01, two-way ANOVA. C-D. Western blotting analysis of the protein levels of HER2, phosphorylated Akt, total Akt, phosphorylated ERK1/2 and total ERK1/2 in MCF-7 cells and MCF-7R cells transfected with Beclin 1 siRNA or control siRNA in the presence of tamoxifen. GAPDH was used as the loading control. All experiments were repeated at least three times. The representative results were shown in the upper panels, and the quantitative results analyzed by Image J software were shown in the lower panels. **p<0.01, Student's t-test.