INHIBITION OF POLYCYCLIC AROMATIC HYDROCARBON-INDUCED NEOPLASIA BY NATURALLY OCCURRING INDOLES

  • 1 January 1978
    • journal article
    • research article
    • Vol. 38  (5) , 1410-1413
Abstract
Indole-3-carbinol, 3,3''-diindolylmethane and indole-3-acetonitrile, 3 indoles occurring in edible cruciferous vegetables, were studied for their effects on 7,12-dimethylbenz(a)anthracene-induced mammary tumor formation in female Sprague-Dawley rats and benzo(a)pyrene-induced neoplasia of the forestomach in female ICR/Ha mice. When given by p.o. [oral] intubation 20 h 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 3 indoles inhibited benzo(a)pyrene-induced neoplasia of the forestomach in ICR/Ha mice. The identification of dietary constituents that can inhibit chemical carcinogens may be of value in understanding the balance of factors that determines the neoplastic response to these cancer-producing agents in the environment.