Hypermethylation at CpG islands of GSTP1 gene’s promoter is the typical property of breast cancer in Vietnamese population

Abstract

The demand for biomarker that applied in prognosis, early diagnosis, predicting and/or monitoring the therapeutic response and detection of recurrent cancer is the worldwide expection. One of the biomarker, which the worldwide researches focused on, is the hypermethylation at CpG island of promoter which undergoes the DNA methylation changes in carcinogenesis. In current study, the target gene is GSTP1 (Glutathion-S-transferase pi 1 gene), with one of the most function is particularly involved in detoxification. Because of this function, GSTP1 (obviously based on the frequencies of methylation) has been chosen as a potential candidate gene for several clinical trials in predicting of the response to the demethylation drugs in several cancers, including breast cancer. In this study, we foscused on the evaluation of the methylation status of 115 biopsy specimens collected from university medical center HCMC, including 95 breast cancer specimens and 20 noncancerous breast tissue. The results showed that  41 of 95 (43.2 %) breast cancer specimens are hypermethylated, no methylation was found on the noncancerous breast tissue (p<0.01). These results allowed us to predict the totally corresponding to the application of the treatment, which based on the demethylation drug, one of the epi-drug line, in Vietnamese patients in the near future.