Quercetin reverses EGF-induced epithelial to mesenchymal transition and invasiveness in prostate cancer (PC-3) cell line via EGFR/PI3K/Akt pathway

Epidermal growth factor (EGF) plays an important role in metastasis and tumorigenesis of prostate cancer. Epithelial-mesenchymal transition (EMT) is a process in tumor progression during which cancer cells undergo dramatic changes acquiring highly invasive properties. The purpose of this study was to determine the effect of quercetin on EGF-induced EMT in prostate cancer (PC-3) cell line. Quercetin, a plant flavonoid, prevented EGF-induced invasion and migration of PC-3 cells. The protein and mRNA expressions of E-cadherin and N-cadherin were studied by immunocytochemistry, Western blotting and real-time polymerase chain reaction. Quercetin prevented EGF-induced expression of N-cadherin and vimentin and increased the expression of E-cadherin in PC-3 cells, therefore preventing EGF-induced EMT. EGF-induced cell adhesion proteins, intercellular adhesion molecule and vascular cell adhesion molecule were significantly decreased by quercetin treatment. Furthermore, mRNA and protein expressions of Snail, Slug and Twist showed that quercetin significantly decreased EGF-induced expressions of Snail, Slug and Twist. The protein expressions of epidermal growth factor receptor (EGFR)/phosphatidylinositide 3-kinases (PI3K)/Akt/extracellular signal-regulated kinase (ERK)1/2 pathway showed that quercetin prevents EGF-induced EMT via EGFR/PI3k/Akt/ERK1/2 pathway and by suppressing transcriptional repressors Snail, Slug and Twist in PC-3 cells. Thus, it is concluded from the present study that quercetin may prevent cancer metastasis by targeting EMT.