微RNA-198在结直肠癌中调控Elf3的表达并抑制细胞增殖

MicroRNA-198 regulates Elf3 expression and inhibits cell proliferation in colorectal cancer

目的 :分析并验证调控E74样因子3(E74-like factor 3,Elf3)表达的微RNA(microRNA,miRNA),并探索该miRNA对结直肠癌细胞功能的影响。方法 :运用数据库miRGen Targets、miRNA Viewer及MicroCosm Targets分析调控Elf3表达的miRNA。根据miRNA序列设计miRNA模拟物及抑制因子,应用miRNA转染技术改变结直肠癌SW1116细胞中该miRNA表达水平后,采用实时荧光定量-PCR法和蛋白质印迹法检测Elf3表达水平的变化。同时,提取30例结直肠癌组织及对应癌旁正常黏膜组织的RNA,反转录并实时荧光定量-PCR检测该miRNA和Elf3的表达水平。FCM和MTT法分别检测该miRNA模拟物转染对结直肠癌SW1116细胞周期、凋亡和增殖能力的影响。结果 :数据库分析显示,微RNA-198(microRNA-198,miR-198)可调控Elf3表达。应用其模拟物转染可显著提高结直肠癌SW1116细胞中miR-198水平(P<0.01),并下调Elf3表达(P<0.01);相反,miR-198抑制因子转染可显著降低miR-198的水平(P<0.01),并上调Elf3的表达(P<0.01)。同时,与癌旁正常黏膜组织相比,结直肠癌组织中miR-198表达水平降低(P<0.01),且与Elf3表达呈负相关(P<0.001,r2=0.697 3)。miR-198模拟物转染可抑制结直肠癌细胞增殖(P<0.01),但对细胞周期和凋亡没有明显影响(P>0.05)。结论 :miR-198在结直肠癌中可调控Elf3的表达,并抑制结直肠癌细胞增殖。

Objective： To analyze and validate a type of microRNA regulating the expression of E74- like factor 3 （Elf3）, and to investigate the effect of miRNA on the function of human colorectal cancer cells. Methods： Databases miRGen Targets, miRNA Viewer and MicroCosm Targets were used to detect the microRNA regulating Elf3 expression. MicroRNA analogues （mimics and inhibitor） transfection technique was applied to change the expression level of microRNA in colorectal cancer cell line SW1116. The expression of Elf3 after transfection with microRNA analogues was detected by real-time fuorescence quantitative-PCR （RFQ-PCR） and Western blotting. Total RNA was extracted from 30 cases of colorectal cancer tissues and corresponding adjacent normal mucosa tissues to detect the expressions of miRNA and Elf3 by RFQ-PCR. The biological effects of the microRNA mimics on the cell cycle distribution, apoptosis and proliferation of SWl 116 cells were detected by flow cytometric assay and MTT assay, respectively. Results： Database analysis showed that microRNA-198 （miR-198） regulated the expression of Elf3. miR-198 mimics transfection effectively up-regulated the miR-198 expression and down-regulated the Elf3 expression in colorectal cancer cells （P 〈 0.01）; while miR-198 inhibitor transfection effectively down-regulated the miR-198 expression and up-regulated the Elf3 expression （P 〈 0.01）. Compared with the corresponding adjacent normal mucosa tissues, miR-198 expression in colorectal cancer tissues was down-regulated （P 〈 0.01）, and negatively associated with Elf3 expression （P 〈 0.001, r2 = 0.697 3）. miR-198 mimics inhibited the proliferation of colorectal cancer SW1116 cells （P 〈 0.01）, but had no impact on cell cycle and apoptosis （P 〉 0.05）. Conclusion： miR-198 can regulate the expression of Elf3 in colorectal cancer, and suppress the proliferation of colorectal cancer cells.