Statistical analysis of the immunohistochemical results revealed that nuclear, but not cytoplasmic or total, FOXK2 expression is marginally correlated with total FOXO3a expression (Pearson coefficient r=0.238, *P=0.054; *P⩽0.05=significant) in all the invasive ductal carcinoma cases (Figure 9a; Supplementary Figure S9). Here, FOXO3 is linked to invasive ductal breast carcinoma.