Inhibition of polycyclic aromatic hydrocarbon-induced neoplasia by naturally occurring indoles.
Indole-3-carbinol, 3,3'-diindolylmethane, and indole-3-acetonitrile, three indoles occurring in edible cruciferous vegetables, have been studied for their effects on 7,12-dimethylbenz(a)anthracene-induced mammary tumor formation in female Sprague-Dawley rats and on benzo(a)pyrene-induced neoplasia of the forestomach in female ICR/Ha mice. When given by p.o. intubation 20 hr prior to 7,12-dimethylbenz(a)anthracene administration, indole-3-carbinol and 3,3'-diindolylmethane had an inhibitory effect on mammary tumor formation, but indole-3-acetonitrile was inactive. Indole-3-carbinol when added to the diet for 8 days prior to challenge with 7,12-dimethylbenz(a)anthracene inhibited mammary tumor formation, whereas indole-3-acetonitrile did not. Dietary administration of all three indoles inhibited benzo(a)pyrene-induced neoplasia of the forestomach in ICR/Ha mice. The identification of dietary constituents that can inhibit chemical carcinogens ultimately may be of value in understanding the balance of factors that determines the neoplastic response to these cancer-producing agents in the environment.
D015127:9,10-Dimethyl-1,2-benzanthracene; D000097:Acetonitriles / Q000494:pharmacology; D000818:Animals; D001551:Benz(a)Anthracenes; D004032:Diet; D005260:Female; D007211:Indoles / Q000494:pharmacology*; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000517:prevention & control*; D051379:Mice; D008813:Mice, Inbred ICR; D009374:Neoplasms, Experimental / Q000517:prevention & control; D051381:Rats; D013274:Stomach Neoplasms / Q000139:chemically induced / Q000517:prevention & control*
D000097:Acetonitriles; D001551:Benz(a)Anthracenes; D007211:Indoles; D015127:9,10-Dimethyl-1,2-benzanthracene; C016516:indole-3-acetonitrile; C016517:indole-3-carbinol; C016392:3,3'-diindolylmethane