TGFB1 and breast cancer: Further analysis of three published microarray studies, including a 99 patient cohort with pathology subtype from Memorial Sloan-Kettering Cancer Center (hereafter MSKCC-99) [35], a 186 patient cohort with intrinsic subtype from University of North Carolina Chapel Hill (hereafter UNCCH-186) [30], and a 159 patient cohort also with intrinsic subtype from University Hospital, Stockholm, Sweden (hereafter Stockholm-159) [31], the only significant results were Wnt (p = 0.001) and TGF-β (p = 0.035) in the Stockholm-159 basal-like BC subtype (Additional file 3: Figure S2D-F).