中文摘要：

目的探讨敲低miR-2，表达抑制裸鼠皮下荷U87人脑胶质瘤生长的疗效和机制。方法原位注射miR-21反义寡聚核苷酸（AS—miR-2I）台疗裸鼠皮下荷U87人脑胶质瘤，定时测量肿瘤大小评估原位注射AS—miR-21的治疗效果，使用RT—PCR和原位杂交方法鉴定治疗后miR-2，表达水平．采用HE染色和免疫组织化学染色（增殖细胞核抗原、细胞周期抑制因子-21、基质金属蛋白酶-9和隔蛋F1—7）评价治疗后肿瘤生物学性状的变化，TUNEL法检测肿瘤细胞凋亡。结果肿瘤生长曲线显示AS—miR-21治疗组肿瘤生长速度及体积明显小于对照组与无义序列治疗组，差异有统计学意义（F=6．056．P=0．007）；RT—PCR检测显示AS—miR-21治疗组miR-21表达下调为对照组的（0．031±0．008）％：原位杂交硅示AS—miR-21治疗组miR-21表达水平较对照组与无义序列治疗组下调：组织病理学检测表明AS—miR-21治疗后肿瘤恶性度降低；TUNEL法检测可见AS—miR-21治疗组细胞凋广数明显高于对照组与无义序列治疗组．差异有统计学意义（F=141．021．P=0．0001。结论 以miR-21作为靶点治疗异种移植U87人脑胶质瘤效果令人满意．miR-21可作为人脑胶质瘤基因治疗的侯选靶点。

英文摘要：

Objective To study the suppressive effect of knockdown ofmiR-21 on the U87 human glioma xenografl growth and the possible mechanism. Methods Nude mice bearing U87 human glioblastoma subcutaneously were treated with miRNA-21 antisense oligonucleotides （AS-miR- 21） intratumorally every 3 d until the observation period ended. The tumor volume of the mice treated with AS-miR-21 was measured regularly as compared with that in the control untreated mice and in the mice treated with scramble oligonucelotides （ODN）. Finally, the tumors were removed from nude mice for the examination, ln-situ hybridization and real-time PCR were conducted to detect the miRNA expression of miR-21. The biological characteristics of the tumors were evaluated by HE and immunohistochemical staining, and the cell apoptosis was detected by TUNEL method. Results During the observation period, the tumor growth was delayed and the final tumor volume of AS-miR-21 treated group was smaller than that in the control and scramble ODN treated group （F=6.056, P=0.007）. The expression of miRNA precursor was knocked down in As-miRNA treated tumors compared with that in untreated or scramble ODN treated tumors. Histopathological examination exhibited the appearance of degraded malignancy. The expressions of PCNA and MMP-9 were down-regulated while Septin-7 and P21 were up-regulated and apoptotic index was increased significantly （F=141.021, P=-0.000） as well. Conclusion The suppressive effect of anti-miR-21 ODNs on the growth of U87 human glioma xenografts is significant and miR-21 can be taken as a candidate for gene therapy of human glioma.