CpG retrieval of DNA from formalin-fixed pathology specimen for promoter methylation analysis

摘要

The present invention provides a method, referred to as CpG retrieval, to overcome incomplete bisulfite modification of DNA recovered from formalin-fixed tissue samples. The method involves boiling deparaffinized tissue samples in citrate buffer, followed by DNA extraction for promoter methylation analysis. In general, the extracted DNA is further modified by sodium bisulfite and then subjected to a method of promoter methylation analysis. The present invention also reports that hypermethylation of ataxia-telangiectasia-mutated gene promoter is correlated with decreased overall survival in patient with head and neck squamous cell carcinoma.