ERBB2 and breast neoplasm: A significant subpopulation of the ductal breast tumor collection [44% (21/48)] showed positive immunostain for nuclear KLF6 and ERBB2 overexpression (Chi-square and Fisher exact tests p values equal to 0.005 and 0.003, respectively; Fig. 4B); analysis of the tumor population overexpressing only ERBB2 revealed that the seventy-eight percent (21/27) of ductal breast tumor tissues expressed nuclear KLF6 (Table 3).