KRT5 and breast cancer: A rich repertoire of keratins is expressed in different epithelial cells, depending of cell type, period of embryonic development, stage of histological differentiation, cellular growth environment, disease state, etc. We screened our scRNA-seq data for expression of different keratins, besides KRT5 and KRT14, which are bona fide BC markers in the airways and lung, but also in bladder (Colopy et al., 2014), prostate (Hudson et al., 2001) and mammary gland (Jumppanen et al., 2007), or for KRT8, which is clearly associated with luminal cell types (Rock et al., 2009).