Tumorigenic compound

The relative stability of l, 2 -epoxyvinylbital, and the great instability of its diol, can be gainfully compared with the fate of the corresponding metabolites of phenyl vinyl ether (10.69, R = H) and 4-nitrophenyl vinyl ether (10.69, R = N02), two mutagenic and tumorigenic compounds [144] [145]. Their primary metabolic route is by vinyl epoxidation to the corresponding... 

In the laboratory of S. Kumar, the synthesis of phenolic derivatives of frans-7,8-dihydroxy -7,8-dihydrobenzo[a]pyrene, a highly tumorigenic compound, was accomplished. The frans-vicinal diol functionality was introduced by using the "dry" Prevost conditions. The alkene was subjected to a mixture of iodine and silver benzoate in dry refluxing benzene to give a good yield of the corresponding frans-7,8-dibenzoate derivative. 

In their review of tumorigenic aromatic amines in which fused ring polycychc amines are discussed. Gamer et al. (1275a) neither mention nor hst quinoline as a tumorigenic compound... 

It is not appropriate to generali2e the carcinogenicity of this class of compounds. Nitrofura2one appears to increase the incidence of benign mammary tumors in rats. The tumorigenic activity of fura2ohdone is expressed by an increase in the incidence of spontaneous tumors in both mice and rats. Bioassays of nitrofurantoin in several species of mice and rats failed to reveal any evidence of direct tumorigenic activity. Ovarian tumors have been reported in B C F mice, but these are beheved due to an indirect expression of toxicity (14,15). 

Some laboratory studies with rats and mice have linked trichloroethylene exposure to various types of cancers. Several of these studies, however, should be viewed cautiously, since the tumorigenic activity might be influenced by the presence of direct-acting compounds, namely the epoxides (e.g., epichlorohydrin) added as stabilizers in trichloroethylene. Epoxides are known to be very reactive, and some, such as epichlorohydrin, are potent carcinogens themselves. 

As safe nutrient ingredients in many food systems, as well as available from commercial synthesis, the combination of vitamins C and E represents very useful compounds for the nutritional inhibition of formation of tumorigenic N-nitroso compounds. 

Carcinogenesis research has demonstrated the tumorigenic activities of a large number of chemical substances in experimental animals. These include molecules of diverse chemical classes, organic and inorganic, and natural products as well as compounds synthesized in the laboratory or produced by industry. 

Inhibition of tumorigenicity by peri methyl substitution. The methylated PAH shown are less tumorigenic than other methyl isomers in the same series or than their parent compounds. References 5,12-dimethylchrysene (14) 4,9-dimethylphenanthrene... 

Comparative tumorigenicity on mouse skin of 5-MeC, 5,11-dimethyl-chrysene, and 5,12-dimethylchrysene. Each compound (5 pg) was applied to mouse skin 3 times weekly for 50 weeks. 

Computerized data-base versions of RTECS give the capability of extracting substance lists by "Classification Codes." For example, one might ask the system to search for all compounds with classification Code of TUMORIGEN. How many users will have read the user s guide carefully enough to know that this means only that these compounds may have been reviewed by IARC or NTP but NOT that they have been indicted as tumorigenic ... 

Not all of the biochemical events in this complex pathway from PPAR-alpha activation to tumors are completely understood, but much is known. It seems that at least some peroxisome-proliferating chemicals that also produce tumors in rodent livers do so through this pathway. If it can be demonstrated that such a mechanism is at work, then it seems that the risk of tumorigenicity for such compounds would be limited to doses that are sufficient to activate PPAK-alpha sufficiently to initiate the dangerous cascade of events within the cell. Experts have developed a number of experimental criteria that should be met if a compound is to be put in this class of carcinogens. Study of P PAR-alpha activation as a route of carcinogensis is an extremely active area of research. 

AAF is classified as a cytotoxic teratogen. Because of demonstrated carcinogenicity in animals, contact by all routes should be avoided. In recent years this compound has been used only in laboratories as a model of tumorigenic activity in animals. It is of little occupational health importance. 

The 16(17)-ene compounds 10 and 13 were protonated at the D-ring double-bond to form stable a-Phe-substituted carbocations. Although the ease of formation and stability of both carbocations lOH" " and 13H+ implicated their potency, compound 13 is a stronger tumorigen than 10, which led to the suggestion of an additive effect. 

A series of thieno[2,3- ]pyridine derivatives has been studied as cytotoxic agents against a tumorigenic cell line. Compound 156 is found to be the most potent derivative in the series <2004BML3411>. 

Another health hazard associated with exposure to UV radiation is the potential cocarcinogenic activity of UV light with the contaminant on the skin. Past studies have found that exposure to UV radiation results in a significant enhancement of the effects of chemical carcinogens such as 7,12-dimethyl benzanthracene (13) and benzo[a]pyrene (14). Even normally innocuous compounds such as anthracene, n-decane and n-tetradecane can develop tumorigenic activity in mice under irradiation with long-wavelength (>350 nm)... 

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