EFFECT OF LIPID EXTRACTS OF FECAL WATER FROM COLORECTAL TUMOR PATIENTS ON DNA-SYNTHESIS IN SWISS 3T3 CELLS

Background: Alterations in the proliferative activity of the colonic epithelium play a central role in the development of human colon cancer. It has been suggested that crypt cell hyperproliferation may partly be due to cell regeneration after exposure to cytotoxic surfactants in fecal water. Methods: The present study determined whether lipid extracts of fecal water from colorectal tumor patients had the capacity to influence DNA synthesis in growing and quiescent Swiss 3T3 cells, at concentrations at which no cytotoxicity was evident. Results: Four of five such extracts significantly increased DNA synthesis in growing cells but were without effect on quiescent cells. Comparison of the effects of the lipid extracts on the cells with that of bile acids, compounds that have received much attention as potential regulators of proliferation, indicated that the effect of the lipid extracts could not solely be attributed to bile acids. Conclusions: Lipid components of fecal water may also influence cell proliferation through mechanisms other than cytotoxicity.