Fig. 4

EGFR is involved in ERK phosphorylation in EC cell lines. All EC cells were transfected with 10 nM of siRNA (control, EGFR, or HER-2). Cells were harvested 48 h after transfection to evaluate ERK phosphorylation after knockdown of EGFR (a) or HER-2 protein (b). Cells were incubated with EGF (1 ng/mL) for 10 min and harvested for western blot analysis. The detection of β-actin protein served as a loading control. The blot is representative of three independent experiments. The expression levels of phosphorylated ERK were quantified by scanning the digital image and digitized data were analyzed with the Image J. Data represent the means ± SEMs of three independent experiments. *, decreased compared to siRNA control transfection (NC), P < 0.05. c All EC cells were transfected with 10 nM of siRNA (control, EGFR or HER-2), and cell proliferation was monitored after 48 h using WST-1 assay. *, increased compared to no treatment cell, P < 0.05.**, decreased compared to siRNA control transfection (Negative Control), P < 0.05