Effects of RNA interference-mediated silencing of vascular endothelial growth factor receptor-2 on proliferation, migration, invasion, and radiation-induced effects in Calu-1 cells / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate the effects of vascular endothelial growth factor receptor?2 ( VEGFR?2) on proliferation, migration, invasion, and apoptosis after radiotherapy in lung cancer cell line Calu?1, and to explore the probable mechanisms. Methods Small interference RNA ( siRNA )?mediated silencing of VEGFR?2 gene was performed on Calu?1 cells, and the mRNA and protein expression of VEGFR?2 was determined by quantitative real?time PCR and Western blot, respectively. The cells were divided into control group, vascular endothelial growth factor ( VEGF ) group, VEGFR?2 specific siRNA (siKDR) group, and siKDR+VEGF group. The changes in proliferation, migration, and invasion were evaluated by the CCK8 assay, cell scratch wound?healing assay, and transwell migration assay, respectively. The protein expression of VEGFR?2 and proteins in the related downstream signaling pathway was measured by Western blot. Apoptosis in each group was determined after radiotherapy. Results After RNA interference?mediated silencing of VEGFR?2, the mRNA and protein expression of VEGFR?2 was significantly reduced ( P=0. 001,P=0. 000);the proliferation, migration, and invasion of Calu?1 cells were also significantly reduced ( P=0. 000,P=0. 000,P=0. 000);the phosphorylation levels of AKT, ERK 1/2, and p38 were significantly reduced in Calu?1 cells ( P=0. 336,P=0. 986,P=0. 553);the apoptosis in Calu?1 cells was significantly elevated ( P=0. 0012);the protein expression of HIF?1α was significantly inhibited ( P= 0. 016 ) . Conclusions The VEGFR?2 gene silencing significantly inhibits several physiological functions of Calu?1 cells and elevates the apoptosis rate after radiotherapy.