Zhang Song, Guo Changkai, Kong Weijia, Liu Zheng
Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
J Huazhong Univ Sci Technolog Med Sci. 2006;26(1):101-4. doi: 10.1007/BF02828051.
The relationship between hypermethylation of CpG islands in the promoter regions of O6-methylguanine DNA methyltransferase (MGMT) genes and laryngeal squamous cell carcinoma was explored. Methylation-specific PCR and semi-quantitative RT-PCR were used to study the promoter methylation and mRNA expression of the MGMT gene in laryngeal carcinoma tissues, tissues adjacent to the tumor and normal laryngeal tissues. Hypermethylation of MGMT gene was detected in 16 samples of 46 (34.8%) laryngeal squamous cell carcinoma samples. However, the MGMT hypermethylation was not detected in all tissues adjacent to the tumors and normal tissues. No significant difference in MGMT gene hypermethylation was found in samples with different histological grades (chi2 = 3.130, P = 0.077) or in samples from patients with different TNM status (chi2 = 3.957, P = 0.138). No expression of MGMT mRNA was detected in all hypermethylated laryngeal carcinoma tissues. The expression of MGMT mRNA was detected in all unmethylated laryngeal carcinoma tissues, tissues adjacent to the tumors and normal tissues. It suggests that MGMT gene promoter hypermethylation is associated with MGMT gene transcription loss in laryngeal carcinoma tissues and possibly plays an important role in carcinogenesis of laryngeal tissues.
探讨了O6-甲基鸟嘌呤DNA甲基转移酶（MGMT）基因启动子区域CpG岛的高甲基化与喉鳞状细胞癌之间的关系。采用甲基化特异性PCR和半定量RT-PCR研究MGMT基因在喉癌组织、癌旁组织及正常喉组织中的启动子甲基化及mRNA表达情况。在46例喉鳞状细胞癌样本中的16例（34.8%）检测到MGMT基因高甲基化。然而，在所有癌旁组织和正常组织中均未检测到MGMT高甲基化。不同组织学分级的样本（χ2 = 3.130，P = 0.077）或不同TNM分期患者的样本（χ2 = 3.957，P = 0.138）中，MGMT基因高甲基化无显著差异。在所有高甲基化的喉癌组织中均未检测到MGMT mRNA表达。在所有未甲基化的喉癌组织、癌旁组织及正常组织中均检测到MGMT mRNA表达。这表明MGMT基因启动子高甲基化与喉癌组织中MGMT基因转录缺失相关，可能在喉组织癌变过程中起重要作用。
