CD44 and colorectal carcinoma: The CD44+ CRC cells exhibit markedly increased invasion, migration, and tumor formation in vivo when compared to the CD44− CRC cells, which is mainly due to the downregulation of colonic epithelial markers (e.g., E-cadherin, CK20 and CDX1) and upregulation of EMT-associated transcriptional factors, including Snail, Twist and Slug.