Promoter methylation status of PTEN, SYK and survivin genes in breast cancer tissues derived from Chinese women

ABSTRACT

Background: Epigenetic mechanisms of gene transcription, including inactivation of tumor suppressor genes by hypermethylation and activation of oncogenes by hypomethylation, have been shown to contribute to breast tumorigenesis. Phosphatase and tensin homolog deleted on chromosome ten (PTEN) and Spleen tyrosine kinase (SYK) are both tumor suppressor genes and survivin is a novel member of the inhibitor of apoptosis (IAP) family which may promote tumorigenesis.Objective: To investigate the methylation status of PTEN, SYK, and survivin genes in breast cancer derived from Chinese women.Materials and methods: We examined the methylation status of these three genes in 52 paraffin-embedded breast cancer tissues using methylation-specific PCR (MSP) assay in conjunction with sequencing analysis.Results: PTEN and SYK were both methylated in 15.4% (8/52) of breast tumor tissues, while the survivin gene was all demethylated in the examined samples. Random selection of MSP products sequence analyses to three genes all revealed a homogenous methylation status in the CpG sites.Conclusion: The present study showed a moderate methylation status of PTEN and SYK, and an unmethylation status of survivin in breast tumor tissues derived from Chinese women, which suggested methylation mechanisms might be involved in the aberrant expression of these three genes in breast cancer development.