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
Liu Yi*, Liu Liang, Hu Chenxi, Zhou Lihua, Qiao Yun, Wang Lei, Liu Bin, Chen Hui, Jiang Xiaodong
*Xuzhou Medical College Graduate Academy, Xuzhou 221000, China
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, ERK1/2, 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.
Liu Yi,Liu Liang,Hu Chenxi et al. 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[J]. Chinese Journal of Radiation Oncology, 2015, 24(6): 714-718.
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2015, Vol. 24 
