Although many pancreatic CSC markers have been reported, such as CD24, CD44, epithelial surface antigen (ESA) [112], CD133 [109], CD184 (C-X-C chemokine receptor type 4, CXCR4), side population (SP) [113], nestin [114], and c-Met [115], relatively few studies have determined the underlying mechanisms regarding how these CSC markers regulate the stemness or tumorigenicity of PC. This evidence concerns the gene CXCR4 and pachyonychia congenita.