Suppression of Hela cell growth and increase in nuclear size by chemical carcinogens: a possible screening method.

HeLa cell monolayers were "pulse" treated with either carcinogenic or "non-carcinogenic" chemicals. Pre-carcinogens were added with a liver homogenate to provide an appropriate metabolizing system. All proximate carcinogens and a proportion of pre-carcinogens were able to inhibit cell division, and in all cases examined, this was accompanied by nuclear enlargement. Although several "non-carcinogenic" chemicals also arrested cell division, nuclear enlargment was not produced. The possibility that growth inhibition and nuclear enlargement in cells treated briefly with a chemical could provide a rapid indication of carcinogenic activity is discussed.