This may occur partly because an increased HA-rich matrix may support invasion by providing cancer cells with a suitable microenvironment (Knudson et al, 1989), stimulate cell motility via interactions of HA with cell-surface receptors (Yang et al, 1993), or form a barrier for cancer cells against host immunocompetent cells (McBride and Bard, 1979). This evidence concerns the gene CD177 and cancer.