KRT18 and cancer: Hence, most of the tumors were basal‐like cancers, 15.625% (5/32) were luminal‐like K18+ only, and 18.75% (6/32) were both K14+ and K18+ (Figure 2B,D) and had mixed K14+ or K18+ cells or K14+/K18+ double‐positive cells (Figure S2A–C, Supporting Information), revealing their transition status.