The murine gastric carcinoma cell lines as well as the primary gastric carcinomas mimic closely human gastric carcinomas and derived cell lines in expressing CEA (when established from tumor-bearing CEA-transgenic mice)[29], upregulate CEACAM1[30], downregulate E-cadherin expression[31] and express EpCAM[32]. The gene discussed is CEACAM1; the disease is neoplasm.