RNA结合蛋白RBM38表达对胶质瘤细胞增殖、迁移、侵袭能力的影响

摘要

To investigate the expression level of RNA-binding motif protein 38 (RBM38) in glioma tissues and cells , and to identify its effects on the proliferation , migration, invasion and apoptosis of glioma cells.Methods RBM38 mRNA levels in glioma tissues and normal adjacent tissues were analyzed using qRT-PCR(quantitative real-time PCR).RBM38 levels in glioblastoma cell line U87, U251and human astrocyte HA1800 cells were detected using qRT-PCR and Western Blot.Additionally, the correlation between RBM38 expression in glioma tissues and the corresponding clinical pathological characteristics of the patients was explored , based on the IHC results of RMB38 expression in 59 human glioma tissues.Specific small interfering RNAs targeting RBM38 were transfected into glioma cell lines U87 and U251 using liposome-mediated transfection.The effects of RBM38 on the proliferation, migration, invasion and apoptosis of glioma cells were examined by CCK-8 proliferation assay , scratch assay , transwell chamber assay and flow cytometry assay respectively.The qRT-PCR was conducted to detect the P53 expression in the RBM38-depleted glioma cells.Results The expression of RBM38 in glioma tissues was significantly higher , in comparison with that of normal adjacent tissues ( P＜0.05).RBM38 levels were significantly up-regulated in glioma cell , compared with those in normal cells (all P＜0.001). Immunohistochemical results indicated RBM 38 expression was higher in high-grade gliomas compared with low-grade gliomas ( P ＜0.05 ).The inhibition of RBM38 expression resulted in significantly reduced proliferation rate of U 87 and U251 cells(P＜0.05), suppressed migration and invasion capacity of glioma cells ( P＜0.05), and significantly enhanced apoptosis rate of glioma cells(P ＜0.05 ).The expression level of P53 gene was significantly increased in the RBM 38-depleted glioma cells(P＜0.05).Conclusions RBM38 expression is remarkably high in glioma tissues and cell lines.The high expression level of RBM38 is closely related to the clinical grade of glioma.Down-regulation of RBM38 can inhibit the proliferation, migration, invasion of glioma cells, promote cellular apoptosis , and improve the expression of P53 gene.The data demonstrate that RBM38 can be used as novel target for the clinical diagnosis and intervention of glioma.%目的 探讨RNA结合蛋白RBM38(RNA结合基序蛋白38,RNA-binding motif protein 38)在胶质瘤组织和细胞中的表达水平及其对胶质瘤细胞增殖、迁移、侵袭和凋亡的调节作用.方法 采用实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)检测胶质瘤组织和瘤旁正常组织的RBM38表达水平.采用qRT-PCR和Western blot检测胶质瘤细胞U87、U251和正常星形胶质细胞HA1800的RBM38表达水平.用免疫组化染色检测59例胶质瘤组织的RBM38表达水平,并分析其与临床病理资料的关系.将靶向RBM38的特异性小干扰RNA运用脂质体介导转染法转染至胶质瘤细胞U87和U251.应用CCK-8(cholecystokinin-8)增殖实验、划痕实验、Transwell小室实验、流式细胞仪测凋亡细胞,检测RBM38对于胶质瘤细胞增殖、迁移、侵袭和凋亡能力的影响.采用qRT-PCR检测抑制RBM38表达后肿瘤细胞P53基因的表达水平.结果 相较于瘤旁的脑组织,胶质瘤组织RBM38的表达量明显升高(P＜0.05).胶质瘤细胞中的RBM38表达水平明显高于正常胶质细胞(均P＜0.001).免疫组化结果显示,与低级别胶质瘤相比,高级别胶质瘤的RBM38 表达水平更高(P＜0.05).抑制RBM38的表达后,胶质瘤细胞U87和U251的增殖速率明显下降、迁移距离变短、能透过生物膜的细胞数目明显下降(均P＜0.05).下调了RBM38的表达后胶质瘤细胞的凋亡比率升高(P＜0.05).被抑制了RBM38表达的胶质瘤细胞P53基因的表达水平升高(P＜0.05).结论 RBM38在胶质瘤组织及细胞系中呈高表达,RBM38的高表达与胶质瘤的临床分级密切相关.下调RBM38的表达后能抑制胶质瘤细胞的增殖、迁移、侵袭能力,促进细胞的凋亡,并使P53基因的表达水平增高;可能为临床诊断和治疗胶质瘤提供新的靶点.