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目的:探讨O6-甲基鸟嘌呤-DNA甲基转移酶(MGMT)在脑膜瘤组织中的甲基化状态及其对人脑膜瘤细胞系IOMM-Lee细胞生长和转移的作用。方法:收集本院34例脑膜瘤患者的标本，甲基化特异的PCR(MSP)法检测脑膜瘤组织和正常脑组织中MGMT甲基化水平，免疫组织化学染色检测脑膜瘤组织和正常脑组织中MGMT表达。将培养的人胶质瘤细胞系IOMM-Lee细胞分为空白对照组(正常培养的IOMM-Lee细胞)、阴性对照组(空载体病毒转染IOMM-Lee细胞)和RNAi慢病毒转染组(转染RNAi慢病毒载体下调MGMT表达的IOMM-Lee细胞)，通过RNAi技术沉默IOMM-Lee细胞中MGMT的表达，实时荧光定量PCR和Western blot检测细胞中MGMT mRNA与蛋白表达水平，CCK-8实验检测细胞增殖活性，细胞克隆形成实验检测细胞克隆形成能力，Transwell实验和细胞划痕实验分别检测各组细胞侵袭与迁移能力。结果:脑膜瘤组织中MGMT甲基化达到88.23%(30/34)，正常脑组织中未检测到MGMT甲基化；脑膜瘤组织中MGMT染色强度较正常脑组织明显增加。与空白对照组和阴性对照组比较，RNAi慢病毒转染组IOMM-Lee细胞中MGMT mRNA和蛋白相对表达量均显著下降(均n P<0.05)，转染24、48和72 h后IOMM-Lee细胞增殖活性显著下降(均n P<0.05)，细胞克隆形成数目、细胞侵袭数目显著下降(均n P<0.05)，同时，细胞划痕愈合率显著降低(n P<0.05)。n 结论:MGMT在人脑膜瘤组织中多呈高甲基化，沉默脑膜瘤细胞中MGMT表达可抑制脑膜瘤细胞生长与转移。“,”Objective:To investigate the methylation status of O6-methylguanine-DNA methyltransferase (MGMT) in meningioma tissue and its effect on the growth and metastasis of human meningioma cell line IOMM-Lee cells.Methods:The specimens of 34 patients with meningioma were collected. Methylation-specific polymerase chain reaction (MSP) method was used to detect MGMT methylation in meningioma tissue and normal brain tissue; immunohistochemical staining was used to detect the expression of MGMT in meningioma tissue and normal brain tissue. The cultured human glioma cell line IOMM-Lee cells were divided into blank control group (normal cultured IOMM-Lee cells), negative control group (empty vector virus transfected IOMM-Lee cells) and RNAi lentivirus transfection group (transfected with RNAi lentivirus vector to down-regulate the expression of MGMT). The expression of MGMT in IOMM-Lee cells was silenced by RNAi technology. The expression levels of MGMT mRNA and protein in cells were detected by real-time fluorescence quantitative PCR and Western blot. The proliferation activity of cells was detected by cell counting kit-8 (CCK-8) test, the colony forming ability was detected by cell clone formation test, and the invasion and migration ability of cells in each group were detected by Transwell test and cell scratch test.Results:The methylation of MGMT in meningioma tissue reached 88.23% (30/34). MGMT methylation was not detected in normal brain tissue; the staining intensity of MGMT in meningioma tissue was significantly higher than that in normal brain tissue. Compared with the blank control group and the negative control group, the relative expression of MGMT mRNA and protein in IOMM-Lee cells of the RNAi lentiviral transfection group were significantly decreased (all n P<0.05). After 24, 48 and 72 hours of transfection, the proliferation activity of IOMM-Lee cells decreased significantly (alln P<0.05), with reduced number of cell clone formation and cell invasion (alln P<0.05). The rate of scar healing decreased significantly (n P<0.05).n Conclusions:MGMT is mostly hypermethylated in human meningiomas. Silencing the expression of MGMT in meningiomas can inhibit the growth and metastasis of meningiomas.