RASSF6介导凋亡与自噬提高奥沙利铂对胃癌细胞的化疗敏感性

RASSF6 plays a role in suppressing cancer and improving the sensitivity of oxaliplatin in gastric cancer cells

目的探讨RASSF6基因对胃癌细胞增殖、自噬、凋亡及对奥沙利铂化疗敏感性的影响。方法体外培养胃癌BGC823细胞,依据慢病毒基因表达分为正常对照组(control组)、RASSF6过表达组(Oe组)、RASSF6干扰组及慢病毒对照组。分别检测各组细胞增殖、细胞周期分布、细胞迁移、自噬、凋亡变化及对奥沙利铂化疗的敏感性,电镜观察各组细胞自噬小体数,荧光定量PCR(qRT-PCR)和蛋白免疫印迹(Western blotting)检测各组细胞凋亡和自噬相关基因的表达。结果 RASSF6基因表达对胃癌BGC823细胞生物学行为的影响,与control组相比,Oe组细胞G0/G1期细胞百分比升高,G2期、S期细胞百分比降低,差异有统计学意义(P<0.05);细胞凋亡率明显增加,差异有统计学意义(P<0.05);细胞划痕面积划痕愈合率显著下降,差异均具有统计学意义(P<0.05)。RASSF6基因表达对奥沙利铂药物敏感性的影响,与药物组(L-OHP组)相比,Oe+L-OHP组细胞凋亡率升高,差异有统计学意义(P<0.05);Western blotting检测示Oe+L-OHP组细胞抗凋亡蛋白Bcl-2表达下降,促凋亡蛋白Bax、Caspase-3表达升高,细胞自噬小体增多,自噬相关蛋白Beclin-1、P62表达及LC3-Ⅱ/LC3-Ⅰ比值升高(P<0.05)。结论 RASSF6过表达可抑制胃癌细胞增殖,促进细胞自噬和凋亡并提高胃癌细胞对奥沙利铂化疗敏感性。RASSF6基因可作为胃癌治疗新的靶点。

Objective To investigate the effects of RASSF6 gene on gastric cancer cells’ proliferation,autophagy,apoptosis,and sensitivity to oxaliplatin chemotherapy. Methods Gastric cancer BGC823 cells were cultured in vitro and divided into experimental control group(control group), RASSF6 overexpression group(Oe group), RASSF6 interference group, and lentivirus control group according to the expression effect of lentivirus gene. The changes in cell proliferation,cell cycle distribution,cell migration,autophagy,apoptosis and sensitivity to oxaliplatin in each group were detected, and the number of autophagy bodies in each group was detected by electron microscopy. Real-time PCR(qRTPCR)and Western blotting were used to detect the expression levels of apoptosis-and autophagy-related genes in each group. Results Studies on the biological behavior of gastric cancer BGC823 cells induced by RASSF6 gene expression showed that compared with the control group, the percentage of G0/G1 phase cells in the Oe group increased, while the percentage of G2 and S phase cells decreased,with statistical significance(P<0. 05). The apoptosis rate was significantly increased(P<0. 05). The cell scratch assay showed that the scratch healing rate was significantly decreased(P<0. 05).Studies on the sensitivity of RASSF6 gene expression to oxaliplatin showed that compared with the drug group(L-OHP group), the apoptosis rate of Oe+L-OHP group was increased significantly(P<0. 05). In the Oe+L-OHP group, the expression of anti-apoptotic protein Bcl-2 decreased,the expressions of Bax and Caspase-3 were increased;the expression of autophagosomes was increased;the expressions of Beclin-1 and P62 and the ratio of LC3-Ⅱ/LC3 were all increased(P<0. 05). Conclusion The RASSF6 gene plays a role in suppressing gastric cancer cell BGC823, which can increase the sensitivity to oxaliplatin chemotherapy by promoting apoptosis and autophagy.