【摘要】 目的研究miR-33a对结直肠癌细胞增殖的影响及其作用机制。方法采用Real-time PCR检测miR-33a在人结直肠癌组织和细胞系中的表达。转染miR-33a抑制剂和类似物到人结直肠癌细胞中,通过CCK8实验检测结直肠癌细胞的增殖活性。通过Real-time PCR检测转染miR-33a抑制剂后结直肠癌细胞中SIRT6 mRNA的表达。采用双萤光素酶报告基因系统探索miR-33a与SIRT6的作用机制。结果 miR-33a在结直肠癌组织和结直肠癌细胞系HCT116中的表达均高于癌旁组织和对照细胞系(P<0.05)。转染miR-33a抑制剂后结直肠癌细胞的增殖活性显著低于对照细胞系(P<0.05)。结直肠癌组织和细胞中SIRT6的mRNA表达水平均低于癌旁组织和对照细胞系(P<0.05)。转染SIRT6后,结直肠癌细胞增殖活性被显著抑制。双萤光素酶报告基因结果显示,过表达miR-33a后,野生型3’-UTR报告载体的萤光素酶活性被明显抑制,而突变型3’-UTR报告载体的萤光素酶活性无明显变化。在HCT116细胞中抑制miR-33a的表达后,SIRT6 mRNA的水平显著升高(P<0.05)。结论miR-33a可以通过抑制SIRT6的表达来促进结直肠癌细胞的增殖。更多还原

【Abstract】 Objective To investigate the effect of miR-33a on proliferation of colorectal cancer cell line and its mechanism. Methods The expression of miR-33a in human colorectal cancer tissues and cells lines was detected by Real-time PCR. The miR-33a inhibitors and analogues were transfected to human colorectal cancer cells, the proliferative activity of colorectal cancer cells was examined by CCK8 assay. The expression of SIRT6 mRNA in colorectal cancer cells was detected by Real-time PCR, after colorectal cancer cells were transfected with miR-33a inhibitor. Double luciferase reporter gene system was used to investigate the mechanism of miR-33a and SIRT6. Results Compared with adjacent tissues and control cell line, miR-33a was higher expression in colorectal cancer tissues and colorectal cancer cell line(HCT116)( P<0.05). The proliferative activity of colorectal cancer cells after transfection with miR-33a inhibitors was significantly lower than that of the control cell line(P<0.05). The expression levels of SIRT6 mRNA in colorectal cancer tissues and cells after transfection of miR-33a inhibitors were lower than those in the adjacent tissues and control cell line( P < 0. 05), the proliferation of colorectal cancer cells was significantly inhibit after transfection with SIRT6. The results of double luciferase reporter gene showed that the SIRT6 3’-UTR reporter gene activity of the wild type 3’-UTR reporter vector was markedly inhibied, and of the mutant type 3’-UTR reporter vector had no significant change after miR-33a overexpression. After the inhibition expression of miR-33a in the HCT116 cell, the level of SIRT6 mRNA increased significantly(P<0.05). Conclusion miR-33a can promote the proliferation of colorectal cancer cells by inhibiting the expression of SIRT6.更多还原