Effects of protease inhibitors on growth of hamster tumor cells in culture.

Abstract

Beef pancreas trypsin inhibitor has been shown to promote parallel alignment of hamster tumor cells in culture and to increase the adhesiveness of rounded cells. It has a slightly depressing effect upon cell proliferation. Soybean inhibitor depressed cell proliferation but had no effect upon cell alignment. Egg white inhibitor had no effect upon proliferation or cell alignment. The synthetic protease inhibitor N -α- p -tosyl-l-lysine chloromethyl ketone HCl had no effect upon cell alignment but depressed cell proliferation. It was toxic in concentrations in excess of 20 µm. Beef pancreas trypsin inhibitor had no effect upon cell proliferation or cell interaction of nontumorigenic hamster embryo cells in culture. The results suggest that some aspects of the morphology and social behavior of the tumor cells studied may be associated with protease activity that can be inhibited by beef pancreas trypsin inhibitor.