Two-stage mouse skin model

Phenol was tested for carcinogenicity by oral administration in drinking-water in one strain of mice and one strain of rats. No treatment-related increase in the incidence of tumours was observed in mice or in female rats. In male rats, an increase in the incidence of leukaemia was observed at the lower dose but not at the higher dose. Phenol was tested extensively in the two-stage mouse skin model and showed promoting activity (lARC, 1989). 

Singh A, Shukla Y. Antitumor activity of diallyl sulfide in two-stage mouse skin model of carcinogenesis. Biomed Environ Sci 1998 11 258-263. 

Figure 2 Inhibitory effect of topical application of rooibos and honeybush extracts on skin tumor development over a 20 week period in a two-stage mouse skin carcinogenesis model (Data are from reference 54)...

As already shown, tubeimoside 1 (5) from Bobolstemma paniculatum exhibited a strong anti-tumor activity, but had intriguingly a potent antitumor-promoting effect in two-stage mouse skin tumor formation induced by DMBA+TPA [38]. Its natural analog, tubeimoside III showed also a potent anti-tumor-promoting effect in the same model after topical administration but not after oral administration [39]. 

Azuine MA, Tokuda H, Takayasu J, et al. (2004) Cancer chemopreventive effect of phenothiazines and related tri-heterocyclic analogues in the 12-O-tetradecanoyl-phorbol-13-acetate promoted Epstein-Barr virus early antigen activation and the mouse skin two-stage carcinogenesis models. Pharmacology Research 49 161-169. 

Caffeic acid phenethyl ester (CAPE), an active component extracted from honeybee propolis, blocks tumorigenesis in a two-stage model of mouse skin cancer that was promoted by treatment with TP A (49). The anti-cancer or antitumor promotion effects of CAPE may be based on their ability to induce apoptosis. We foimd that CAPE suppresses TPA-induced cell transformation and induced apoptosis in mouse epidermal JB6 Cl 41 cells (50). No difference in induction of apoptosis was observed between normal lymphoblasts and sphingomyelinase-deficient cell lines. Although CAPE treatment of two p53 mutant tumor cell lines, NCI-H358 and SK-OV-3, and p53 cells caused... 

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