P-Selectin on platelets and endothelium binds cell surface chondroitin sulfate (CS) proteoglycans, which are abundantly and stably expressed on the surface many cancer cells. Binding of the cancer cells through the CS moieties may be blocked to inhibit the interaction of cancer cells with platelets and endothelium. The present inventors disclose compositions and methods for the inhibition of cancer metastasis.
1. A method of treating breast cancer comprising: administering to a patient an antibody against Melanoma Chondroitin Sulfate Proteoglycan (MCSP), wherein the antibody specifically recognizes MCSP in its form with chondroitin sulfate (CS) attached to MCSP and does not bind to MCSP in its form without CS attached to MCSP and reduces interaction between P-selectin and cells expressing MCSP and comprising chondroitin sulfate (CS).