EFFECT OF O-GLYCOSYLATED MUCIN ON INVASION AND METASTASIS OF HM7 HUMAN COLON-CANCER CELLS

Mucinous colorectal cancers have a poorer prognosis than colorectal ca ncers which produce a low amount of mucin, but the exact mechanism is not well understood. The present study was undertaken to elucidate the possible mechanisms of invasion and metastasis of colon cancer cells producing high levels of mucin using mucin glycosylation inhibitor, be nzyl-alpha-N-acetylgalactosamine. The binding activity of treated HM7 cells to endothelial leukocyte adhesion molecule (ELAM-1) was signific antly decreased and fixed cell binding of MoAb SNH-3 and 19-9 (specifi c for sialyl Le(x) and sialyl Le(a) respectively) was also significant ly decreased. Metalloproteinase activity in conditioned medium and inv asion of matrigel-coated porous filters by treated HM7 cells were decr eased. However, there was no difference between control and treated HM 7 cells in terms of matrix protein binding. These results suggest that O-glycosylated mucin is important in the invasive and metastatic prop erties of HM7 human colon cancer cells. (C) 1996 Academic Press, Inc.