多发性骨髓瘤细胞和正常浆细胞miR-373表达水平及其对肿瘤生长的影响

Expression of miR-373 in multiple myeloma cells and normal plasma cells and its effect on tumor growth

目的分析多发性骨髓瘤细胞和正常浆细胞microRNA-373(miR-373)表达水平及其对肿瘤生长的影响。方法回顾性收集江苏大学附属句容医院收治的36例多发性骨髓瘤患者为病例组,另同期选取30例于该院健康体检者为对照组。采用实时荧光定量PCR法测定病例组细胞与对照组正常浆细胞中miR-373的表达量。通过Lipofectamine-2000将miR-373模拟物(转染miR-373组)或相应的阴性对照(阴性对照组)转染为H929细胞。分析H929细胞中细胞增殖、细胞周期和凋亡及肿瘤生长的情况。结果实时荧光定量PCR法检测结果显示,病例组细胞中miR-373的相对表达量(0.40±0.04)较对照组正常浆细胞的水平(1.02±0.05)显著下降(P <0.01)。细胞增殖实验表明,相比阴性对照转染的H929细胞,经转染miR-373模拟物的H929细胞中miR-373表达明显升高(P <0.01)。细胞周期实验结果发现,相比阴性对照组,转染miR-373组的H929细胞在S期的细胞百分比较低,而在G0/G1期的细胞百分比较高(P <0.01)。细胞凋亡实验结果发现,相比阴性对照组,转染miR-373组的H929细胞凋亡率明显增高(P <0.01)。小鼠成瘤实验表明,miR-373的过表达可通过下调叉头框蛋白M1(FOXM1)表达以明显阻滞肿瘤生长(P <0. 01)。结论 miR-373可通过调节FOXM1表达以发挥有效阻滞多发性骨髓瘤肿瘤生长的作用,提示其对多发性骨髓瘤的临床治疗具有重要意义。

Objective To analyze the expression level of microRNA-373( miR-373) in multiple myeloma cells and normal plasma cells and its effect on tumor growth. Methods Thirty-six patients with multiple myeloma in our hospital were selected as the case group,and 30 healthy persons in our hospital were selected as the control group at the same time. Real-time fluorescence quantitative polymerase chain reaction was used to detect the expression of miR-373 in plasma cells of case group and control group. The cell proliferation,cell cycle,apoptosis and tumor growth were analyzed by animal model. Results Real-time fluorescence quantitative PCR showed that the relative expression of miR-373 in the case group( 0. 40±0. 04) was significantly lower than that in the control group( 1.02±0.05)( P < 0.01). Compared with H929 cells transfected with negative control,the expression of microRNA-373 in H929 cells transfected with miR-373 was significantly increased( P <0.01). Compared with H929 cells transfected by negative control,the percentage of H929 cells transfected by miR-373 in S phase was decreased,while that in G0/G1 phase was increased( P < 0.01). Compared with H929 cells transfected by negative control,the apoptotic rate of H929 cells transfected by miR-373 was significantly increased( P < 0.01). Mice tumorigenesis experiment showed that the overexpression of miR-373 could significantly inhibit the growth of tumors by down-regulating the expression of fork-headed frame protein M1( FOXM1)( P <0.01). Conclusion miR-373 can effectively block the growth of multiple myeloma tumors by regulating the expression of FOXM1,suggesting that it is of great significance in the clinical treatment of multiple myeloma.