A number of CRC biomarkers and cancer therapy target genes, such as carcinoembryonic antigen (CEA) [26], Coding Region Determinant-Binding Protein [27] and Cripto-1 [28], Trophoblast glycoprotein (5T4) [29] are shown to be regulated in such manner, i.e. expressed in tumors, whereas their expression in normal tissues is mainly limited to pre-natal period. This evidence concerns the gene CEACAM5 and cancer.