Carcinogens inhibition

The impact of xenobiotics on health can occur in a number of ways. As we have noted, the xenobiotic can be a carcinogen, be metabolized to a carcinogen, inhibit the detoxification of... 

Tetrachlorodibenzo-/ - mental toxic, carcinogenic inhibition (at l-10nM)]... 

Forty-eight derivatives of berberine-type alkaloids were examined for their inhibition activity against the induction of mouse ear edema via application of 12-O-tetradecanoylphorbol-13-acetate (TPA). Berberrubine chloride displayed inhibitory effects (ED50 1.3 pmol/ear 52% inhibition). Berberine derivatives had stronger inhibitory activity than palmatine derivatives. Since berberine and some of its derivatives are present in Chinese traditional drugs, which are used in combined Kampo prescriptions, it is important to determine if such alkaloids possess carcinogenic inhibiting properties [221]. 

CLAs reportedly suppress carcinogens, inhibiting proliferation of leu-... 

Carotenoids, mainly lycopene, have been used in the treatment of cardiovascular and degenerative diseases, besides prostate, stomach, and lung cancers acting on possible modulation mechanisms of carcinogens, inhibition of cell proliferation, increase of cell differentiation by retinoids, stimulation of intercellular... 

Acrylonitrile is beheved to behave similarly to hydrogen cyanide (enzyme inhibition of cellular metaboHsm) (150) and is befleved to be a potential carcinogen (151). It can also affect the cardiovascular system and kidney and Hver functions (150). Eurther information on the toxicology and human exposure to acrylonitrile is available (152—154) (see Acrylonitrile). 

Interferons (lENs) (52,53), a family of species-specific vertebrate proteins, confer nonspecific resistance to a broad range of viral infections, affect cell proliferation, and modulate immune responses. AH three principal interferons, a-interferon (lEN-a) produced by blood leucocytes, P-interferon (lEN-P) by fibroblasts, and y-interferon (lEN-y) by lymphocytes, also have antiviral activity. The abiUty of interferons to inhibit growth of transplantable and carcinogen-induced tumor led to research showing the direct antiproliferative and indirect immune-mediated antitumor activities (see Chemotherapeutics, anticancer). IENs have been found to be efficacious in certain malignancies and viral infections, eg, hairy cell leukemia (85% response) and basal cell carcinoma (86% response). However, the interferons do have adverse side effects (54). 

Vinyl chloride -78 (Chloroethene) CH2 CHCI 472 4.0-22.0 1.0 2.1 -14 Colourless, sweet smelling liquefiable gas Polymerizes with light, heat, air or catalysts Normally inhibited Human carcinogen... 

A scientifically evaluated and fully referenced data bank, developed and maintained by the National Cancer Institute (NCI). It contains some 8,000 chemical records with carcinogenicity, mutagenicity, tumor promotion, and tumor inhibition test results. Data are derived from studies cited in primaiy journals, current awareness tools, NCI reports, and other special sources. Test results have been reviewed by experts in carcinogenesis and mutagenesis. 

Human data as well as studies in animals have provided negative evidence of carcinogenicity for endosulfan (Hack et al. 1995 Hoechst 1988b, 1989a). However, endosulfan promoted the development of altered hepatic foci in rats initiated with nitrosodiethylamine (Fransson-Steen et al. 1992). Although the mechanism of tumor promotion of endosulfan is not known, it has been suggested that it involves inhibition of cellular communication (Kenne et al. 1994). A brief discussion of this topic is provided in Section 2.5 under Cancer Effects. 

Must be inhibited Colourless, partially water soluble liquid Experimental carcinogen Polymerizes violently with organic peroxides or concentrated caustic alkalis... 

The mechanism of action for liver toxicity and carcinogenicity may involve the formation of reactive products (Bonse and Henschler 1976 Bonse et al. 1975 Fisher et al. 1991 Larson and Bull 1992b). Methods for reducing the destructive damage caused by these intermediates, or for blocking their formation through inhibition of metabolic pathways may prove effective in reducing hepatic toxicity but are not currently available for clinical use. 

WATTENBERG L (1981) Inhibition of carcinogen-induced neoplasia by sodiiun cyanate, tert-butylisocyanate and benzyl isothiocyanate administered subsequent to carcinogen exposure . Cancer Res, 41, 2991-4. 

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