SDC1 and plasma cell myeloma: A potential difficulty in extending this mechanism to endothelial cells, however, is that endothelial Sdc1, unlike myeloma, is variably decorated with chondroitin sulfate (CS) at sites that either immediately flank (ExSG207) or are within (ExSG217) the VLA-4/VEGFR2 binding region and thus may prevent receptor capture (Figure 7d).