摘要目的:探讨miRNA-126-3p（miR-126-3p）对人单核细胞白血病THP-1细胞增殖和周期的影响。方法:采用实时荧光定量聚合酶链反应（PCR）检测miR-126-3p在THP-1细胞和从2022年5月至2023年1月山西省肿瘤医院收集的4名健康体检者外周血分离的单核细胞中的表达情况。构建过表达miR-126-3p载体，转染THP-1细胞（过表达miR-126-3p组），以转染空载体的THP-1细胞为对照。采用CCK-8法检测各组细胞增殖能力，采用流式细胞术检测细胞周期。应用TargetScan软件预测miR-126-3p靶基因为RGS3，通过双荧光素酶报告基因实验进行验证。采用蛋白质印迹法检测过表达miR-126-3p组THP-1细胞RGS3蛋白表达水平。结果:PCR检测结果显示，与健康人外周血分离的单核细胞相比，THP-1细胞miR-126-3p表达水平低（ P<0.05）。与对照组比较，过表达miR-126-3p组THP-1细胞在培养48 h和72 h后增殖能力均低（均 P<0.05），且细胞G 1期阻滞[G 1期细胞比例：（58.2±2.8）%比（44.1±2.4）%， P<0.05]。双荧光素酶报告基因实验结果显示miR-126-3p与RGS3的3'UTR结合。蛋白质印迹法检测显示，过表达miR-126-3p组THP-1细胞RGS3蛋白表达水平低于对照组。 结论:miR-126-3p可能通过抑制RGS3表达而抑制人单核细胞白血病THP-1细胞增殖和促进细胞G 1期阻滞。

abstractsObjective:To investigate the effects of miRNA-126-3p (miR-126-3p) on proliferation and cycle of human monocytic leukemia THP-1 cells.Methods:Real-time fluorescence quantitative polymerase chain reaction (PCR) was used to verify the expression of miR-126-3p in THP-1 cells and monocytes isolated from the peripheral blood of healthy check-ups collected from May 2022 to January 2023 in Shanxi Cancer Hospital. The miR-126-3p overexpression vector was constructed and transfected inyo THP-1 cells (miR-126-3p overexpression group), and THP-1 cells transfected with the empty vector were used as the control. The proliferative ability of cells in each group was detected by CCK-8 assay, and the cell cycle was detected by flow cytometry. TargetScan software was applied to predict the miR-126-3p target gene as RGS3, which was verified by dual luciferase reporter gene assay. The protein expression level of RGS3 in THP-1 cells of the miR-126-3p overexpression group was detected by Western blotting.Results:The results of PCR showed that the expression level of miR-126-3p in THP-1 cells was low compared with that in monocytes isolated from peripheral blood of healthy individuals ( P < 0.05). Compared with the control group, THP-1 cells in the miR-126-3p overexpression group had low proliferative capacity after 48 h and 72 h of culture (both P < 0.05), and the cells were blocked in G 1 phase [proportion of cells in G 1 phase: (58.2±2.8)% vs. (44.1±2.4)%, P < 0.05]. The results of dual luciferase reporter gene assay showed that miR-126-3p bound to the 3'UTR of RGS3. Western blotting assay showed that the RGS3 protein expression level in THP-1 cells of the miR-126-3p overexpression group was lower than that in the control group. Conclusions:miR-126-3p may inhibit proliferation of human monocytic leukemia THP-1 cells and promote G 1-phase blockade by inhibiting the expression of RGS3.