The present invention provides antibodies or antigen-binding fragments thereof that specifically bind the ENDO180 polypeptide and are internalized thereby, to conjugates comprising the molecules, to compositions comprising the antibodies and conjugates and to methods of using the same for delivery of therapeutic agents to cells that express the ENDO180 polypeptide on the surface of the cell for treating cell proliferative diseases or disorders and fibrosis, and for controlling (modulating) tumor progression.