DNA hypomethylation of CAGE promotors in squamous cell carcinoma of uterine cervix.

This study was performed to determine whether promotor hypomethylation of CAGE is involved in cervical carcinogenesis. The surgical specimens of 40 cervical squamous cell carcinoma patients treated at Seoul National University Hospital and those of 48 healthy controls were used, with informed consent. We investigated the promotor hypomethylation status of CAGE by methylation-specific polymerase chain reaction (MSP) using primers specific for unmethylated sequences, and found hypomethylation of CAGE promotor at a frequency approaching 90% in cervical squamous cell carcinomas (35/40, 87.5%), but at less than 4% in controls (P < 0.001). This finding provides experimental evidence of the frequent hypomethylation of normally methylated CAGE promotor CpG islands in cervical cancer, and indicates that this hypomethylation is likely to be a valuable surrogate marker for the expression of CAGE. It also provides a clue concerning the molecular mechanisms of carcinogenesis in cervical squamous cell carcinoma.