This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Parnaud, G. Articles by Corpet, D. E. Search for Related Content PubMed PubMed Citation Articles by Parnaud, G. Articles by Corpet, D. E.

Polyethylene-glycol Suppresses Colon Cancer and Causes Dose-dependent Regression of Azoxymethane-induced Aberrant Crypt Foci in Rats¹

Sécurité des Aliments, Institut National de la Recherche Agronomique, Ecole Nationale Vétérinaire de Toulouse, 31076 Toulouse, France

Dietary polyethylene-glycol (PEG) 8000, a nonfermented polymer laxative, strongly suppresses azoxymethane-induced aberrant crypt foci (ACF) in the colon of rats, as shown in a previous study (D. E. Corpet et al., Carcinogenesis (Lond.), 20: 915–918, 1999). In the present study, we tested the effect of PEG administered during either initiation or postinitiation, the dose-response effect of PEG, the regressive effect of PEG on established ACF, and the preventive effect of PEG on colon cancers in rats. The general design was to initiate carcinogenesis in F344 rats by a single injection of azoxymethane (20 mg/kg) and to randomize the animals 7 days later to AIN-76 diets containing 5% PEG or no PEG (control). At termination, ACF and tumors were scored blindly by a single observer. The administration of 5% PEG for 32 days to groups of 10 female rats in either food or drinking water reduced the number of ACF by a factor of 8 (P = 0.0002) and reduced the number of large ACF by a factor of 20–30 (P = 0.002). No protection was afforded when PEG was given only during the initiation phase. Diets containing 0%, 0.5%, 2%, or 5% PEG fed for 35 days to four groups of male rats inhibited ACF in a dose-dependent manner (P < 0.0001). The administration of a 5% PEG diet for 41 days, starting 42 days after carcinogen injection, led to a 73% decrease in the number of ACF (P < 0.0001). Dietary PEG thus caused the regression of established ACF. Macroscopic tumors were evaluated by histology in rats that had been fed a high-fat diet containing cooked casein to promote tumor growth for 81 days. In this accelerated model of carcinogenesis, dietary PEG suppressed the occurrence of colon adenomas and carcinomas: the incidence of tumors decreased from 70% to 10% (P = 0.005); and the multiplicity decreased from 2.1 to 0.1 tumor(s)/rat (P = 0.003). No cancer was detected in the PEG-fed rats. Taken together, these results suggest that PEG could be a potent anticancer agent in the postinitiation phase of carcinogenesis. Because PEG is a substance that is generally recognized as safe (GRAS list, Food and Drug Administration), its cancer-preventive features could be tested in humans.

This article has been cited by other articles:

				D. E. Corpet and F. Pierre Point: From Animal Models to Prevention of Colon Cancer. Systematic Review of Chemoprevention in Min Mice and Choice of the Model System Cancer Epidemiol. Biomarkers Prev., May 1, 2003; 12(5): 391 - 400. [Abstract] [Full Text] [PDF]

				D. Naigamwalla, M. C. Chia, T. T. Tran, A. Medline, K. Hay, S. Gallinger, and W. R. Bruce Polyethylene Glycol 8000 and Colon Carcinogenesis: Inhibition in the F344 Rat, Promotion in the Min Mouse Cancer Res., December 1, 2000; 60(24): 6856 - 6858. [Abstract] [Full Text]

				D. E. Corpet, G. Parnaud, M. Delverdier, G. Peiffer, and S. Taché Consistent and Fast Inhibition of Colon Carcinogenesis by Polyethylene Glycol in Mice and Rats Given Various Carcinogens Cancer Res., June 1, 2000; 60(12): 3160 - 3164. [Abstract] [Full Text]