Involvement of peanut agglutinin-binding sugar chains in experimental metastasis of B16 melanoma cells

Involvement of PNA (peanut agglutinin)-binding sugar chains in experimental metastasis of B16M4 cells and their metastatic variants (B16F1, B16F10, and B16BL6) was investigated by using ginsenoside Rh2 (Rh2), which increased PNA binding to the cell surface without increasing concanavalin A or wheat germ agglutinin binding. The PNA binding to cell surface increased in parallel with the experimental metastatic ability in Rh2-treated B16M4 cells, and this increase in metastatic ability was suppressed when the cells were treated with PNA before i.v. injection of cells. Concanavalin A and wheat germ agglutinin did not have such inhibitory effects. Increased PNA binding was observed on glycoproteins of M(r) 75,000-85,000, and was suggested to be due to reduced sialylation of PNA-binding sugar chains on these glycoproteins. In Rh2-treated B16F10 and B16BL6 cells, the increase in experimental metastatic ability was also associated with increased PNA binding to cell surface and M(r) 75,000-85,000 glycoproteins. Although the mechanisms of these effects of Rh2 are unknown, these results suggested that the reduced sialylation of PNA-binding sugar chains on M(r) 75,000-85,000 is related to the increased experimental metastatic ability of Rh2-treated B16 melanoma cells.