Viswanathan M, Solomon S P R, Tsuchida N, Selvam G S, Shanmugam G
Department of Biochemistry, Centre for Advanced Studies in Functional Genomics, School of Biological Sciences, Madurai Kamaraj University, India.
Indian J Exp Biol. 2006 Feb;44(2):115-9.
Hypermethylation of promoter regions leading to inactivation of tumor suppressor genes is a common event in the progression of several tumor types. We have employed a novel restriction digestion based multiplex PCR assay to analyse the methylation status of promoter regions of tumor suppressor genes (p16, hMLH1, MGMT and E-cadherin) in sporadic breast carcinomas of Indian women. The present results indicated the absence of hypermethylation in promoter region of p16 and MGMT genes. However, 6 of the 19 (31.6%) sporadic breast carcinomas showed hypermethylation in the promoters of two of the genes analysed; three in hMLH1 and another three in E-cad. Since our earlier studies have shown lack of genetic alterations such as missense mutations and deletions in the tumor associated genes-p16, ras and p14ARF in sporadic breast tumors, the epigenetic alterations of the two genes reported in the present study could be of interest and might be among the events in the genesis/progression of sporadic breast carcinomas.
启动子区域的高甲基化导致肿瘤抑制基因失活，这在几种肿瘤类型的进展中是常见事件。我们采用了一种基于新型限制性消化的多重PCR检测方法，来分析印度女性散发性乳腺癌中肿瘤抑制基因（p16、hMLH1、MGMT和E-钙黏蛋白）启动子区域的甲基化状态。目前的结果表明，p16和MGMT基因的启动子区域不存在高甲基化。然而，19例散发性乳腺癌中有6例（31.6%）在所分析的两个基因的启动子中出现高甲基化；3例在hMLH1中，另外3例在E-cad中。由于我们早期的研究表明，散发性乳腺肿瘤中与肿瘤相关的基因——p16、ras和p14ARF缺乏错义突变和缺失等基因改变，本研究中报道的两个基因的表观遗传改变可能值得关注，并且可能是散发性乳腺癌发生/进展过程中的事件之一。
