Methylation of <i style="">E-cadherin</i> and <i style="">hMLH1</i> genes in Indian sporadic breast carcinomas

Abstract

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 (<i style="">p16, hMLH1, MGMT</i> and <i style="">E-cadherin</i>) in sporadic breast carcinomas of Indian women. The present results indicated the absence of hypermethylation in promoter region of <i style="">p16</i> and <i style="">MGMT</i> genes.<i style=""> </i>However, 6 of the 19 (31.6%) sporadic breast carcinomas showed hypermethylation in the promoters of two of the genes analysed; three in <i style="">hMLH1</i> and another three in <i style="">E-cad</i>. Since our earlier studies have shown lack of genetic alterations such as missense mutations and deletions in the tumor associated genes-<i style="">p16, ras</i> and <i style="">p14^ARF</i> 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.