Tumors, Skin

Diacetylphloroglucinol and its homologues have been prepared and found to be inhibitors of the herpes vims (188). Syzygiol (50), a skin tumor promotion inhibitor, has been prepared from phloroglucinol (189). The first natural morphogen (cell-differentiation agent) (51) has also been identified as a phloroglucinol derivative (190). 

Melanoma A skin tumor containing dark pigment. 

Wattenberg EV (2007) Palytoxin exploiting a novel skin tumor promoter to explore signal transduction and carcinogenesis, Am J Physiol Cell Physiol 292 C24—C32... 

The main indications for deep chemical peel include dyschromia, wrinkles, premalignant skin tumors, and acne scars. 

LU Y p, LOU Y R, xiE J G, YEN p, HUANG M T and coNNEY A H (1997) Inhibitory effect of black tea on the growth of established skin tumors in mice effects on tumor size, apoptosis, mitosis and hromodeoxyuridine incorporation into DNA , Carcinogenesis, 18 (11), 2163-9. 

WEI H, TYE L, BRESMiK E and BiRT D F (1990) Inhibitory effect of apigenin, a plant flavonoid, on epidermal ornilthine decarboxylase and skin tumor promotion in mice . Cancer Res, 50, 499-502. 

Guyton, K. Z. Bhan, P. Kuppusamy, P. Zweier, J. L. Trush, M. A. Kensler, T. W. Free radical-derived quinone methide mediates skin tumor promotion by butylated hydroxytoluene hydroperoxide expanded role for electrophiles in multistage carcinogenesis. Proc. Natl. Acad. Sci. USA 1991, 88, 946-950. 

Guyton, K. Z. Thompson, J. A. Kensler, T. W. Role of quinone methide in the in vitro toxicity of the skin tumor promoter butylated hydroxytoluene hydroperoxide. Chem. Res. Toxicol. 1993, 6, 731-738. 

Mathews-Roth M. M. and Krinsky N. I. (1984). Effect of dietary fat level on UV-B induced skin tumors, and anti-tumor action of beta-carotene. Photochem Photobiol 40(5) 671-673. 

DiGiovanni, J. and T.J. Slaga. 1981a. Effects of benzo(e)pyrene [B(e)P] and dibenz(a,c)anthracene [DB(a,c)A] on the skin tumor-initiating activity of polycyclic aromatic hydrocarbons. Pages 17-31 in M. Cooke and A.J. Dennis (eds.). Chemical Analysis and Biological Fate Polynuclear Aromatic Hydrocarbons. Fifth International Symposium. Battelle Press, Columbus, OH. 

Nessel, C.S., et al., The role of dermal irritation in the skin tumor promoting activity of petroleum middle distillates, Toxicol. Sci., 49, 48, 1999. 

Kripke, M. L., Antigenicity of murine skin tumors induced by UV light, J. Natl. Cancer Inst. 53, 1333-1336, 1974. 

Section 8 of TSCA has made EPA and the industry aware of nitrosamine contamination in metalworking fluids. In one particular potentially significant notice of substantial risk (8E-1077-0 012), skin painting studies showed an increase above the expected normalincidence of tumors in the livers and lungs of mice with no unusual incidence of skin tumors. Due to the similarity between the observed effects and the mechanism of action of nitrosamines (i.e., the apparent systemic effect of the substance and organ specificity of the tumors), the company attributed the response to a nitrosamine contaminant in the fluid. 

Room temperature has been shown to influence the incidence of skin tumors in mice (Weisbrode and Weiss, 1981). Changes in relative humidity may alter food and water intake (Fox, 1977). Low humidity may cause ringtail, especially if animals are housed in wire mesh cages (Flynn, 1960). 

The initial studies at RIVM demonstrated that exposure of these mice to IV-B radiation or 7,12-dimethylbenz[a]anthracene resulted in the rapid induction of skin tumors. It was also shown that various internal tumors could be induced following... 

It is now widely recognized that age adjustment cannot properly be carried out unless the context of observation is taken into account. There are three relevant contexts, the first two relating to the situation where the condition is only observed at death (e.g., an internal tumor) and the third where it can be observed in life (e.g., a skin tumor). 

Clinical work from Slovenia94 involves treatment of five patients with melanoma skin tumors ECT was combined with systemic chemo- and/or immunotherapy. Tumor mass reductions were observed but no complete responses. 

A second study examined the effects of DMBA initiated mi rex-promoted tumors in female mice on ovarian hormones. This study found that the loss of ovary (OVX) protected the female mice (40%) from mirex tumor promotion. Tumor promotion was unaffected in DMBA-initiated OVX mice promoted with TPA. Based on the data, the authors also concluded that there is a structural specificity in the tumor-promoting ability of mirex in mouse skin and that mirex is a much more effective skin tumor promoter in female CD-1 mice than in male CD-1 mice or OVX mice (Meyer et al. 1994). 

In animal studies, mirex (a nonmutagenic hepatocarcinogen) promoted mouse skin squamous carcinomas and papillomas after initiation with 7,12-dimethyl-benz[a]anthracene (DMBA) for 1 week. Mirex, also, potentiated the promotional potency of the phorbol ester tumor promoter, 12-0 -tetradecanoylphorbol-13-acetate (TPA). There was a 90% incidence (activation) of the c-Ha-ras tumor gene in these co-promoted tumors. When both mirex and TPA gave a similar tumor yield, only the TPA response was associated with biochemical markers of enhanced cell proliferation, induction of epidermal ornithine decarboxylase activity and increased DNA synthesis, and hyperplasia. Thus, there is evidence for a dual effect of mirex during co-promotion first, as an independent tumor promoter with a mechanism different than that of phorbol esters and second, as a compound that also potentiates skin tumor promotion by TPA (Meyer et al. 1993, 1994 Moser et al. 1992, 1993). 

Meyer SA, Kim TW, Moser GL, et al. 1994. Synergistic interaction between the non-phorbol ester-type promoter mirex and 12-o-tetradecanoylphorbol-13-acetate in mouse skin tumor promotion. Carcinogenesis 15(1) 47-52. 

Moser GJ, Robinette CL, Smart RC. 1993. Characterization of skin tumor promotion by mirex structure-activity relationships, sexual dimorphism and presence of Ha-ras mutation. Carcinogenesis 14(6) 1155-1160. 

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