Quantitative detection of metastasis-associated 1 mRNA and protein expression in breast cancer

Objective Understanding the mechanism of breast cancer metastasis will benefit those patients in need of aggressive treatment and avoid side effects caused by chemotherapy over treatment.Recently,a potential metastasis-associated gene and its product,the metastasis-associated 1 (MTA1),were identified; this gene has been found to be overexpressed in a variety of cancers.Methods In the present study,therefore,the level of expression of MTA1 mRNA has been assessed by LightCycler quantitative real-time RT-PCR in 160 cases of invasive carcinoma of the breast.MTA1 protein expression level was also detected by immunohistochemistry from available paired tissues of 154 cases.Associations between MTA1 mRNA and protein expression and clinicopathological factors were analyzed.Results It was found that MTA1 mRNA was expressed at significantly higher levels in patients with negative lymph node status,with ER and PgR positive and HER2 negative tumor.No difference was found between patient age,tumor size and histological grade groups.Patients with high levels of expression of MTA1 mRNA had a better prognosis than those with low expression.However,no difference was found between the protein level and clinicopathological factors.Univariate and multivariate prognostic analysis did not demonstrate that MTA1 mRNA was an independent prognostic factor for breast cancer.Conclusion In breast cancer,inconsistent with other tumor types,MTA1 gene expression is correlated with non-invasive clinicopathological factors and longer survival,which might suggest MTA1 gene is a tumor type specific metastasis associated gene. Key words: Breast cancer ;  Estrogen receptor ;  MTA1 mRNA ;  Progesterone receptor ;  Prognosis ;  Real-time RT-PCR ;