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Indole-3-carbinol: Anticarcinogen or tumor promoter in brassica vegetables?

Department of Environmental Biochemistry, University of Hawaii, Honolulu 96822, USA.
Chemico-Biological Interactions (Impact Factor: 2.98). 04/1998; 110(1-2):1-5. DOI: 10.1016/S0009-2797(97)00115-4
Source: PubMed

ABSTRACT Indole-3-carbinol (I3C) is one of several compounds in brassica vegetables that demonstrate anticarcinogenic effects in experimental animals. A review of Medline and CancerLit databases indicated that interest in I3C, as a cancer chemopreventive agent, has increased significantly in the past 5-10 years. Whereas most studies report inhibitory or protective effects of I3C in vivo, a few provide clear evidence for promotion or enhancement of carcinogenesis, depending upon the initiator, exposure protocol and species. In the absence of detailed information on the inhibitory and in particular, promotional mechanisms, it would seem advisable to proceed with caution before including I3C in extensive human clinical trials.

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    • "This is in agreement with many studies reporting beneficial effects of vegetables and fruit consumption [15] [16]. Nevertheless, some animal experiments with I3C showed an increase in tumor formation after initiation with a carcinogen [17] and ICZ showed a TCDD-like inhibition of gap junction intercellular communication in vitro, indicative of a tumor promotive effect [18]. Also epidemiological studies are inconsistent as to the overall healthy effects of foods containing NAhRAs or vegetables and fruit in general [19] [20] [21]. "
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    • "could be prodrugs for cancer therapy (Chen et al., 2001; Dashwood, 1998; Edwards et al., 1999; Folkes and Wardman, 2001; Greco et al., 2002; Hong et al., 2002; Leong et al., 2001; Rossiter, 2002; Stresser et al., 1995; Wardman, 2002). BNOA has been categorised in the chemical group that demonstrated slightly acute toxicity by the Pesticide Action Network (PAN, 2009) but there are no data on its long-term effects in this site. "
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    • "CYP1A2 induction by concentrated food additives , also can initiate dioxin - like toxic pathways , especially when slow processes like tumor promotion are involved . Besides tumor suppressing capacity , high doses of NAhRAs given to laboratory animals have sometimes also shown tumor promoting capacity ( Dashwood 1998 ) , and the accumulation effect of persistent fat - soluble xenobiotic AhR agonists could be mimicked by constant or regular NAhRA exposure . "
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