KRT5 and cancer: Intriguingly, we found that 55–98% of cancer cells simultaneously expressed classical marker genes (NKX2-1, KRT7, and NAPSA for ADC; TP63, KRT5, and KRT6A for SCC; CHGB, SYP, and NCAM1 for NET) for two or even three different histologic subtypes of NSCLC in the same individual cell (defined as a mixed-lineage cell) in six patients (P5, P10, P11, P13, P19, and P22).