Carcinoembryonic antigen‐related cell adhesion molecule 1 in cancer: Blessing or curse?

Abstract The Carcinoembryonic antigen‐related cell adhesion molecule 1 (CEACAM1, also CD66a), a transmembrane glycoprotein of the immunoglobulin superfamily, is a pivotal mediator of various physiological and pathological processes, including oncologic disorders. However, its precise role in tumorigenicity is contradictory discussed by several clinical studies. This review aims to elucidate the clinical significance of CEACAM1 in different cancer entities focusing on tumour formation, progression and metastasis as well as on CEACAM1‐mediated treatment resistance. Furthermore, we discuss the contribution of CEACAM1 to cancer immunity and modulation of the inflammatory microenvironment and finally provide a comprehensive review of treatment regimens targeting this molecule.