A33R

Antigen 33 related protein (A33R), also named as CD227 or TACSTD2, is a transmembrane glycoprotein encoded by the TACSTD2 gene, predominantly expressed on epithelial cells. Initially identified for its high expression in colorectal cancer, A33R has been found in various epithelial tumors, including those of the breast and ovary. It plays diverse biological roles, including promoting cell adhesion and maintaining the structural integrity and polarity of epithelial tissues. A33R also regulates cell proliferation, differentiation, and signal transduction, with significant impacts on tumor development through interactions with the Wnt/β-catenin signaling pathway. By engaging specific ligands or cell surface molecules, A33R activates downstream signaling pathways that influence the cell cycle and apoptosis. Its high expression in tumor cells makes A33R an important cancer marker and a potential target for early diagnosis, prognosis evaluation, and targeted therapy.