P16070

CD44 also known as HCAM is a 742 amino acid single-pass type I membrane protein that plays a crucial role in cell adhesion and migration, functioning as a receptor for hyaluronic acid (HA) and interacting with ligands like osteopontin (OPN). This interaction is vital for mediating cell-cell and cell-matrix connections, which are essential during processes such as hematopoiesis, lymphocyte activation, and tumor metastasis. HCAM′s structure includes a Link domain and is subject to alternative splicing, resulting in multiple isoforms, including CD44R, CDw44, CD44S, CD44H (hematopoietic), and CD44E (epithelial). CD44H isoform shows high expression in cancer tissues, indicating significant involvement in tumor progression and highlighting HCAM′s importance in both normal physiological processes and pathological conditions.