Gelatinases of murine metastatic tumor cells.

The properties of gelatinases secreted in culture medium of murine fibroblasts, macrophages, colonic carcinoma, FBJ virus-induced osteosarcoma, Lewis lung carcinoma and mammary tumor cells were compared. Normal fibroblasts and macrophages secreted gelatinases of 60,000 and 95,000 molecular weights, respectively. Tumor cells secreted both of these gelatinases, although the relative amounts of the 60 kDa and 95 kDa gelatinases differed among the cell lines. The cell lines that had the greatest metastatic potential to the lung secreted the highest amount of 95 kDa gelatinase. The 95 kDa gelatinase produced by tumor cells had properties similar to that of macrophages.