Oncogenic role of SIRT1 associated with tumor invasion, lymph node metastasis, and poor disease-free survival in triple negative breast cancer

The aim of this study is to evaluate the biological role and clinical implications of silent mating type information regulation 2 homolog 1 (SIRT1) as a novel candidate for target therapy in triple negative breast cancer (TNBC) for which there is no specific agent. 344 patients who received surgical resection for TNBC from January 2003 to December 2006 at Seoul National University Hospital were enrolled, and the role of SIRT1 protein was evaluated via immunohistochemistry on tissue samples. In vivo experiments to evaluate tumor invasiveness were carried out with three human TNBC cell lines following SIRT1-siRNA transfection. Expression of SIRT1 significantly correlated with lymph node metastasis (p = 0.008). In multivariate analysis, SIRT1 expression (p = 0.011), T stage (p = 0.014), and lymphatic invasion (p