多种siRNA的抗肿瘤作用研究

Study of the antitumor activities of siRNAs

目的:研究短干扰RNA(short interfering RNA,siRNA)的抗肿瘤作用。方法:采用MTT法检测siR-NA的生长抑制作用,H&E染色法观察细胞形态变化,TUNEL标记法检测核DNA断裂,Western Blot法分析蛋白表达水平变化和流式细胞法检测细胞周期分布变化。结果:siRNA-Bcl2,siRNA-MDM2,siRNA-CDK2和siRNA-HRas可以明显抑制人乳腺癌MCF-7等肿瘤细胞的生长;siRNA-MDM2和siRNA-Bcl2可以引起MCF-7细胞染色质凝集;siRNA-Bcl2,siRNA-MDM2,siRNA-CDK2和siRNA-HRas均可以明显降低靶基因的表达水平,同时诱导MCF-7细胞发生染色体DNA断裂;siRNA-MDM2还可以导致MCF-7细胞发生G1期阻滞。结论:siRNA可以明显抑制肿瘤细胞的生长,降低靶基因的表达水平,并诱导肿瘤细胞凋亡和周期阻滞,提示siRNA可能发展成为一类高效特异的新型抗肿瘤药物。

Objective:To study the antitumor activity of short interfering RNA (siRNA). Methods: The growth inhibitory effect of siRNA was measured by MTT assay. The cytomorphosis and DNA fragmentation of siRNA were respectively observed by H&E staining and TUNEL labeling method. The protein level and changes of cell cycle distribution were detected respectively by western blot assay and flow cytometry. Results:Data indicated that the growth of MCF-7 cells was obviously inhibited by siRNA-Bcl2, siRNA-MDM2, siRNA-CDK2 and siRNA-HRas and their chromatin conden-sation and DNA fragmentation could be induced by siRNA-MDM2 and siRNA-Bcl2; target gene ex-pression level could be significantly reduced by siRNA-Bcl2, siRNA-MDM2, siRNA-CDK2 or siRNA-HRas as well as GI phase arrest of MCF-7 cells could be blocked.Conclusion:That siRNA can inhibit the growth of tumor cells, suppress expression level of target genes, induce apoptosis and GI arrest of tumor cells may become a cancer gene therapy.