ABSTRACT
Objective To observe the methylation and expression of 14-3-3 sigma gene in human breast cancer.Methods 40 breast cancer tissues and 18 mammary gland tissues with benign lesions were analyzed by methylation specific PCR(MSP),RT-PCR,and Western-blot(WB)so as to detect the methylation status and expression of 14-3-3 sigma mRNA or protein.Results Methylation of 14-3-3 sigma gene was detectable in 85%(34/40)of patients with breast cancers.RT-PCR showed negative in 12.5% of breast cancers(5/40),WB also indicated that 14-3-3 sigma was not detected in 32 of 40 breast carcinomas (80%).Furthermore,both RT-PCR and WB were negative in 30 of 34 positive cases by MSP.While methylation of 14-3-3 sigma was not detectable and its expression was demonstrated by RT-PCR and WB among 18 cases of benign breast diseases.These evidences proposed that methylation of 14-3-3 sigma gene had great relevance with its silence.Conclusion Methylation and loss of expression in 14-3-3 sigma gene were high frequent events in breast cancers.And methylation of 14-3-3 sigma gene might be related to its loss.