GROWTH-SUPPRESSIVE ACTIVITIES OF SERINE-PROTEASE INHIBITORS, FOY-305,ONO-3403 AND FO-349 TOWARD HUMAN CARCINOMA-CELLS

FOY-305 is a synthetic serine protease inhibitor and ONO-3403 and FO-3 49 are its derivatives. The effects of these compounds on the prolifer ation of several human carcinoma cell lines were investigated in vitro by MTT colorimetric assay. ONO-3403 showed the most potent growth-inh ibitory activity among these protease inhibitors. The half maximum inh ibition concentrations of ONO-3403 toward BxPC-3 pancreatic carcinoma, T24 bladder carcinoma and A431 epidermoid carcinoma cells were 20-30 mu g/ml whereas those toward pancreatic carcinomas, PANC-1 and Mia PaC a-2, were 60-80 mu g/ml. Since FOY-305 has been shown to be effective in chemotherapy for human oral cancer, ONO-3403 is expected to be a mo re effective anticancer drug.