Consistent with the observations in breast cancer tissues (Figure 1), there was an inverse association between expression level of CRB3 protein and expression levels of β‐catenin protein, β‐catenin downstream factors (CD44 and cMyc) and cancer stem cell‐associated transcription factors (OCT4 and NANOG) (Figure 5A). This evidence concerns the gene POU5F1 and breast carcinoma.