Cell surface glycoprotein that plays a role in cell adhesion and tumor progression . Intercellular adhesion occurs in a calcium- and fibronectin-independent manner . Mediates homophilic and heterophilic cell adhesion with other carcinoembryonic antigen-related cell adhesion molecules, such as CEACAM5 and CEACAM8 . Heterophilic interaction with CEACAM8 occurs in activated neutrophils . Plays a role in neutrophil adhesion to cytokine-activated endothelial cells . Plays a role as an oncogene by promoting tumor progression; positively regulates cell migration, cell adhesion to endothelial cells and cell invasion .