Such changes include loss of CK7 and acquisition of CK20 in colorectal carcinoma (Park et al, 2002), acquisition of CK7 and loss of CK20 in gastric carcinoma (Park et al, 2002; Kim et al, 2004), or acquisition of CK 1, 5, 6, 8, 19 in squamous cell carcinoma (Xu et al, 1995; Chu and Weiss, 2002b; Ikeda et al, 2008). Here, KRT1 is linked to squamous cell carcinoma.