CEACAM5 and neoplasm: In one of the most comprehensive studies, Garnett et al. (2004) analyzed a panel of 23 human tumor cell lines of colon, lung, and prostate origin for the effect of radiation on expression of MHC-I, Fas, ICAM-1, and two tumor-associated antigens, carcinoembryonic antigen (CEA) and mucin-1 (MUC-1).