Groups of 6 male rats were painted twice weekly with 1 ml of a 0.2% solution of an azo dye in acetone. The dyes used were aminoazobenzene, 4-monomethylaminoazobenzene, their 3methoxy analogs, and 4-dimethylaminoazobenzene. In each case, all rats developed multiple skin tumors of histologie types similar to those found in rats treated with other chemical classes of carcinogen. 3-Methoxy-4-monome...

The effects of sodium cyanate, tert-butyl isocyanate, and benzyl isothiocyanate on carcinogen-induced neoplasia were studied in experiments in which the test compound was fed starting 1 week following completion of carcinogen administrations. Under these conditions, all three test compounds exerted an inhibitory effect on the occurrence of 7,12-dimethylbenz(a)anthracene-induced neoplasia of the...

A marked and progressive decrease in epidermal hydroxyproline accompanied in duced epidermal carcinoma by methylcholanthrene in C3H mice. A decrease was also noted in the benzene-treated controls; but this was reversible, whereas the effect pro duced by the carcinogen was not. A progressive increase in epidermal tyrosine was ob served which was more marked in the carcinogen-treated animals than...

Diabetes mellitus and hepatocellular carcinoma both have detrimental impact on health worldwide. Type II diabetes and liver cancer share many causative factors, but biological correlation between the two diseases still remains elusive. The study was aimed to evaluate the effect of induction of diabetes during the development of hepatocarcinogenesis in rats. Rats were divided into four groups na...

Intragastric administration of 3-methylcholanthrene (MCA) has been reported by others to cause cancers of the glandular stomach and large intestines in an inbred strain of Syrian golden hamsters. In search of the molec ular basis of this process, this study examined the diver sity of the macromolecules and carcinogen-protein com plexes in colon and glandular stomach cytosols during the long-ter...

PURPOSE Nonsteroidal anti-inflammatory drugs (NSAID) are promising chemopreventive agents against colon and other cancers. However, the molecular basis mediated by NSAIDs for chemoprevention has not been fully elucidated. Environmental carcinogens induce DNA mutation and cellular transformation; therefore, we examined the effect of NSAIDs on carcinogenesis mediated by the aryl hydrocarbon recep...

There is much evidence suggesting a possible role of reactive oxygen-derived substances in the pathogenesis of both ulcerative colitis and colon cancer. The antioxidant effects of 5-aminosalicylic acid (the active moiety of olsalazine) on induction of colon cancer in an experimental model using 1,2-dimethylhydrazine were studied in male Wistar rats. The levels of reduced glutathione were signif...

The development of oral squamous cell carcinoma (SCC) shows a positive correlation with the carcinogen exposure that occurs during tobacco and alcohol use. The purpose of this study was to investigate whether the naturally occurring chemopreventive agent, curcumin, modulates expression and function of carcinogen- metabolizing enzymes in human keratinocytes isolated from oral SCC tumors. Dose-re...

In considering the explanation of the recognized influence of the solvent upon the carcinogenic effectiveness of a dissolved carcinogen we have focussed our attention upon the physical factors which affect the availability of the carcinogen to the tissues in situ. An attempted formulation (see Discussion) of a possible mechanism of transfer from the solvent to the nearby affected tissue suggest...