中文摘要：

目的研究miR-378对骨髓增生异常综合征SKM-1细胞凋亡和增殖的影响。方法我们分别用miR-378重组慢病毒和阴性对照病毒感染SKM-1细胞。然后采用CCK-8检测miR-378对SKM-1细胞生长的影响,流式细胞仪检测各实验组细胞凋亡和周期情况,并用Western blot检测凋亡过程中的关键因子cleaved-caspase-3蛋白的表达。用生物信息学方法预测miR-378可能的靶基因,用PCR和Western blot进行初步验证。结果 miR-378慢病毒转染组的细胞增殖活性明显降低,流式细胞术检测miR-378组的细胞凋亡率为（12.90±3.72）%,明显高于阴性对照病毒转染组和空白对照组[（3.21±1.91）%、（2.78±1.04）%,P〈0.01];miR-378组的G0/G1期细胞增多,S期细胞减少。同时,Western blot结果显示miR-378过表达引起了cleaved-caspase-3的表达升高。用生物信息学方法预测抗凋亡蛋白基因BCL2L2为miR-378潜在的靶基因,并发现miR-378可以抑制BCL2L2蛋白的表达。结论 miR-378可以通过引起细胞凋亡和细胞周期阻滞来抑制SKM-1细胞的增殖,并降低BCL2L2蛋白的表达。

英文摘要：

Objective To investigate the effect of miR-378 on apoptosis and proliferation in myelodysplastic syndrome SKM-1 cells. Methods SKM-1 cells were divided into 3 groups： SKM-1 cells transfected with lentiviral vector over-expressing miR-378 （miR-378 group）, SKM-1 cells transfected with empty lentiviral vector （negative control group） and normal SKM-1 （blank control group）. CCK-8 assay and Annexin V/7-AAD staining were conducted to detect the effect of miR-378 on the proliferation and apoptosis of SKM-1 cells. Then, Western blotting was performed to detect the expression of cleaved-capase-3 protein. Bioinformatics analysis was conducted to predict the potential target gene of miR-378, and quantitative reverse transcriptase-polymerase chain reaction and Western blotting were further confirm the target gene. Results After transfection with lentiviral vector over-expressing miR-378, the growth of SKM-1 cells in the miR-378 group was inhibited obviously. The apoptotic rate [（12.90 ± 3.72）%] in the miR-378 group was significantly higher than [（3.21 ± 1.91）%] in the negative control group and [（2.78 ± 1.04）%] in the blank control group （P〈0.01）. The percentage of SKM-1 cells in G0/G1 phase was increased and the percentage in S phase was decreased. Western blotting showed that overexpression of miR-378 resulted in up-regulation of cleaved-caspase-3. Moreover, BCL2L2 gene was predicted as potential target gene of miR-378, and overexpression of miR-378 reduced the expression of BCL2L2 protein. Conclusion miR-378 can inhibit proliferation of SKM-1 cells by inducing apoptosis and cell cycle arrest, and it also down-regulates the expression of BCL2L2 protein.