KRT14 and breast neoplasm: By staining a group of basal-like breast tumors for the basal cell cytokeratin K14, the luminal cytokeratin K18, and the mesenchymal marker vimentin (VIM), Granit found that there were three prominent subpopulations in the tumor samples of invasive TNBC: K14+K18+, K18+ and K18+VIM+, where the K14+K18+ subpopulation was luminal progenitor-like and highly tumorigenic.