目的:探讨人工合成小分子双链RNA-625（double-stranded RNA-625，dsP21-625）对前列腺癌细胞P21 基因的激活作用及对细胞增殖的影响。方法: 将人工合成的dsP21-625（dsP21-625 组）和dsCtrl 质粒（dsCtrl 组）分别转染至前列腺癌细胞株PC-3 和DU-145。用实时荧光定量PCR和Western blotting 分别检测转染后各组前列腺癌细胞中P21、细胞周期素E（Cyclin E）和细胞周期蛋白依赖性激酶2（CDK2）mRNA及蛋白的表达水平，流式细胞术、MTT实验和克隆形成实验分别检测细胞周期分布、细胞增殖和克隆形成能力。结果: 与dsCtrl 组比较，dsP21-625 组PC-3 和DU-145 细胞中P21 mRNA水平升高(均P<0.01)，Cyclin E和CDK2 mRNA表达水平下调（均P<0.01）；dsP21-625 组PC-3 和DU-145 细胞中P21 蛋白表达上调(均P<0.01)，Cyclin E和CDK2 蛋白表达下调（均P<0.01）；dsP21-625 组细胞S 期和G2/M 期的细胞比例减少（均P<0.05），G0/G1 期的细胞比例增加（均P<0.01）；dsP21-625 组细胞增殖活力降低（均P<0.05）、克隆形成数减少（均P<0.05）。结论: dsP21-625 上调前列腺癌细胞中P21 mRNA及蛋白的表达，下调Cyclin E和CDK2 mRNA及蛋白的表达，抑制前列腺癌细胞的增殖能力。

Objective: To study the effects of synthetic small molecule double-stranded RNA-625（dsP21-625）on the activation of P21 gene in prostate cancer cells and its effect on cell proliferation. Methods: dsCtrl (control group) and dsP21-625（experimental group）were transfected into prostate cancer PC-3 and DU-145 cell lines. qPCR and Western blotting were used to detect the mRNA and protein expressions of P21, Cyclin E and cyclin dependent kinase 2（CDK2）in prostate cancer cells of each group after transfection. The cell cycle distribution, cell proliferation and clone formation were analyzed by flow cytometry, MTT assay and colony formation assay,respectively. Results: Compared with dsCtrl control group, P21 mRNA level was elevated in PC-3 cells and in DU-145 cells (all P<0.01) after transfection with dsP21-625; in the meanwhile, the expression of Cyclin E and CDK2 mRNA were down-regulated (P<0.01).The expression of P21 protein in PC-3 and DU-145 cells transfected with dsP21-625 was up-regulated (all P<0.01) while the expressions of Cyclin E and CDK2 proteins were down-regulated (all P<0.01); the proportion of cells in S phase and G2 / M phase decreased (all P<0.05), and the proportion of cells in G0/G1 phase increased (all P<0.01) after dsP21-625 transfection. The cell proliferation ability and colony formation were significantly decreased in dsP21-625 groups (all P<0.05). Conclusion: dsP21-625 can activate the expression of P21 mRNA and protein in prostate cancer cells, down-regulate the expression of Cyclin E and CDK2 protein, and significantly inhibit the proliferation of prostate cancer cells.

湖北省自然科学基金资助项目（No.2017CFB176）