MiR-21在大肠癌中的表达及其对SW480细胞增殖侵袭的影响

Expression of miR-21 in colorectal cancer and the effects of miR-21 on invasion and migration in SW480 cell line

目的检测microRNA-21(miR-21)在大肠癌患者中的表达情况,并探讨miR-21对大肠癌SW480细胞增殖和侵袭的影响。方法收集大肠癌患者标本32例,同时收取癌组织及相应的癌旁组织。通过荧光定量PCR(qRT-PCR)方法检测各组织中miR-21的表达水平。以脂质体为载体将miR-21抑制剂转染至SW480细胞,分别用MTT方法与Transwell实验检测转染后SW480细胞的增殖侵袭能力变化,利用qRT-PCR和免疫印迹实验检测第10号染色体同源缺失的磷酸酶及张力蛋白同源的基因(PTEN)mRNA和蛋白水平的改变。结果 miR-21在32例患者癌组织及正常黏膜组织中的表达量分别为(1.57±0.79)与(0.56±0.32),差异有统计学意义(P<0.01)。下调miR-21的表达能够显著抑制SW480细胞的增殖和侵袭能力,PTEN mRNA和蛋白的表达水平均显著升高(P<0.01)。结论 microRNA-21在大肠癌中高表达,下调microRNA-21表达抑制大肠癌SW480细胞增殖和侵袭可能与上调PTEN表达相关。

Objective To examine the expression of microRNA-21（miR-21） in colorectal cancer, and to investigate the effects of miR-21 on the proliferation and invasion of SW480 cell line. Methods The expression of miR-21 was detected by quantitative real-time PCR（qRT-PCR） in 32 colorectal cancer tissues and their corresponding adjacent tissues. The miR-21 inhibitor was transfected into SW480 cells with Lipofectamine, and then proliferation and invasion ability of SW480 ceils were detected by MTT method and transwell cell invasion assay, qRT-PCR and Western blot were used to examine the mRNA and protein expression of phosphatase and tensin homolog deleted on chromosome ten gene （PTEN） respectively. Results The expression level of miR-21 in the carcinoma tissues and normal tissues of 32 patients were （1.57± 0.79） and （0.56± 0.32） respectively,and with significant difference statistically（P〈0.01）, the proliferation and invasion ability of SW480 cells were markedly inhibited by the inhibition of miR-21, and the mRNA and protein expression of PTEN was upregulated significantly too（P〈0.01）. Conclusion miR-21 was overexpressed in colorectal cancer, the inhibition effect of miR-21 inhibitor on the proliferation and invasion ability of SW480 ceils might be related to the upregulation of PTEN expression.