Human carcinoembryonic antigen functions as a general inhibitor of anoikis

Human carcinoembryonic antigen (CEA), a widely used tumor marker, and CEACA M6 [formerly nonspecific cross-reacting antigen (NCA)] are up-regulated in many types of human cancers, whereas family member CEACAM1 [formerly biliar y glycoprotein (BCP)] is usually down-regulated, Deregulated overexpression of CEA/CEACAM6 but not CEACAM1 can inhibit the differentiation and disrupt the polarization and tissue architecture of man different types of cells. In this report, we show that CEA and CEACAM6, but not CEACAM1, markedly inh ibit the apoptosis of cells when deprived of their anchorage to the extrace llular matrix, a process known as anoikis. By blocking: this tissue archite cture surveillance mechanism, the architectural perturbation initiated by C EA/CEACAM6 can thus be maintained.