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 e pithelium 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 extr acts 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 ce lls but were without effect on quiescent cells. Comparison of the effe cts of the lipid extracts on the cells with that of bile acids, compou nds that have received much attention as potential regulators of proli feration, indicated that the effect of the lipid extracts could not so lely be attributed to bile acids. Conclusions: Lipid components of fec al water may also influence cell proliferation through mechanisms othe r than cytotoxicity.