KRT18 and carcinoma: Post-translational down-regulation of intracellular CK18 protein revealed by phenotypic immunostaining was found to promote cell migration [20] and progression of breast [19] and colon cancers [48], whereas up-regulated CK18 protein was reported to correlate to poor differentiation and advanced stage in lung [49], renal cell [50], oral cavity [51] and esophageal squamous cell [52] carcinomas.