Additionally, when compared the prognosis relationship between SIRT1-low/N1IC-high and SIRT1-high/N1IC-high group, our results showed SIRT1-low/N1IC-high group had worse outcome than the SIRT1-high/N1IC-high group, which confirmed low expression of SIRT1 may be an important indicator for worse survival in N1IC high breast cancer. Here, SIRT1 is linked to breast cancer.