Lysosomal-associated membrane protein 1 (LAMP-1) also known as lysosome-associated membrane glycoprotein 1 and CD107a (Cluster of Differentiation 107a), is a protein that in humans is encoded by the LAMP1 gene. The LAMP-1 glycoprotein is a type I transmembrane protein which is expressed at high or medium levels in at least 76 different normal tissue cell types. It resides primarily across lysosomal membranes, and functions to provide selectins with carbohydrate ligands. LAMP1 expression on the surface of tumor cells has been observed for a number of different cancer types, particularly in highly metastatic cancers such as pancreatic cancer, colon cancer and melanoma. The structure of LAMP1 correlates with differentiation and metastatic potential of tumor cells as it is thought to help mediate cell-cell adhesion and migration.