O6-甲基鸟嘌呤DNA转移酶在神经胶质瘤中的表达及其与亚硝脲耐药的关系

目的 :探讨O6 甲基鸟嘌呤DNA转移酶 (MGMT)在人脑神经胶质瘤中的表达情况及其与亚硝脲耐药之间的关系。方法 :采用免疫组化法对人脑神经胶质瘤石蜡标本中MGMT进行了检测 ,并与临床应用亚硝脲的疗效评价结果进行了比较。结果 :116例神经胶质瘤中MGMT阳性表达率为 6 7.2 %。MGMT阳性表达率最高者为髓母细胞瘤 (10 0 % ) ,表达率最低者为少枝胶质细胞瘤 (35 .7% )。在使用亚硝脲治疗的患者中 ,MGMT阳性表达与亚硝脲化疗效果呈显著负相关 (P <0 .0 5 )。肿瘤细胞的耐药程度与MGMT表达强度无关 ,只与其是否阳性有关。结论 :不同病理类型的神经胶质瘤对亚硝脲的耐药和敏感性明显不同。化疗前检测神经胶质瘤MGMT的表达情况 ,对预测化疗敏感性、指导临床使用亚硝脲化疗具有重要意义。

Expression of O6-methylguanine-DNA methltransferase in human gliomas and its relationship with nitrosourea resistance

Objective:To examine the expression of O 6-methylguanine-DNA methyltransferase (MGMT) in human gliomas and to investigate MGMT expression association with histopathologic type and nitrosourea resistance. Methods: 116 cases of brain glioma were detected with immunohistochemical staining for MGMT and compared these results with nitrosourea chemotherapy. Results: The positive rates for MGMT in gliomas were 67.2% and MGMT expression is different in different histopathologic types of glioma. The highest positive rate was medulloblastoma (100%) and the lowest was oligodendroglioma (35.7%). MGMT expression was inversely correlated with the effectiveness of nitrosourea chemotherapy in gliomas ( P <0.05). Conclusion: Nitrosourea resistance and sensitivity were significantly different in histopathologic type of gliomas. MGMT expression was correlated significantly with nitrosourea resistance. So it is important to detect MGMT before using nitrosourea chemotherapy.