miRNA-34a对胶质瘤SHG-44细胞增殖和凋亡的影响

Effects of miRNA-34a on proliferation and apoptosis of glioma SHG-44 cells

目的:研究微小RNA-34a(microRNA-34a,miR-34a)在人脑胶质瘤组织中的表达以及其对胶质瘤SHG-44细胞增殖和凋亡的影响。方法:20例胶质瘤组织标本均取自于青岛医学院附属医院神经外科(2007年01月至2010年12月),作为对照的正常脑组织取自5位重症脑外伤需行减压手术的患者。Real-time PCR检测胶质瘤组织中miR-34a的表达。体外转染miR-34a mimics至SHG-44细胞中,MTT实验、流式细胞术检测SHG-44细胞的增殖、细胞周期及凋亡。结果:miR-34a在人脑胶质瘤组织中的表达量明显低于正常脑组织,其在Ⅲ、Ⅳ期胶质瘤组织中表达量明显低于Ⅰ、Ⅱ期胶质瘤组织。miR-34amimics体外转染组与空白组相比,其细胞增殖抑制率明显提高[(37.24±5.72)%vs(4.19±0.63)%,P<0.01];miR-34amimics转染组SHG-44细胞G1期比例明显高于空白对照组[(61.78±2.01)%vs(50.91±1.19)%,P<0.05];且miR-34a转染组细胞凋亡率与空白组细胞相比显著升高[(15.28±3.65)%,vs(2.07±0.84)%,P<0.01]。结论:miR-34a在人脑胶质瘤组织中低表达,miR-34a可抑制SHG-44细胞的增殖、诱导细胞周期阻滞和细胞凋亡。

Objective： To investigate the expression levl of microRNA-34a （miR-34a） in human glioma tissues, and fur- ther explore the role of miR-34a on proliferation and apoptosis of glioma SHG-44 cells. Methods： Twenty glioma samples were collected from the Department of Neurosurgery, Affiliated Hospital of Qingdao Medical College （January 2007 to De- cember 2010）. The normal brain tissues were obtained from 5 patients with severe traumatic brain injury who required post- trauma surgery. The expression level of MiR-34a in glioma tissues was detected by real-time PCR. After transfection of miR- 34a mimics into SHG-44 cells, the proliferation, cell cycle and apoptosis were measured by MTY and flow cytometry, respec- tively. Results ： The expression level of miR-34a was lower in the glioma tissues compared with the normal brain tissues, and miR-34a expression level was lower in the glima tissues of phase Ill/IV than in phase 1/11. The cell proliferation inhibitory rate increased signficantly in the miR-34a transfected group compared to the blank group （[37.24±5.72] % vs [4.19 ±0. 63 ] %, P 〈 0.01 ）, the ratio of cells arrest at G1 phase was significantly higher in the miR-34a mimics transfected group compared to the blank group （ [61.78 ±2.011% vs [50.91 ±1. 191%, P 〈0.05）, and the cell apoptosis in the miR-34a transfected group was significantly increased compared to the blank group （ [ 15.28 ± 3.65 ] % vs [ 2.07 ± 0.84 ] %, P 〈 0. 01 ）. Conclusion ： MiR-34a was lowly expressed in human glioma tissues. MiR-34a can inhibit SHG-44 cell proliferation, thus inducing SHG-44 cell cycle arrest and promoting SHG-44 cell apoptosis.