salicylates and Cocarcinogenesis

The petroleum ether extract of cashewnut shell (Anacardium occidentale) was tested for its mutagenic, carcinogenic and cocarcinogenic potency. Mutagenicity tests using Salmonella typhimurium (Ame's test) Strains TA 1535, TA 100 and TA 98 showed that cashewnut shell liquid is non-mutagenic up to a concentration of 0.003% (in 0.1 ml DMSO) with and without metabolic activation (S 9 mixture). Carcinogenicity testing using murine (female Swiss albino mice) two stage skin tumourigenesis model revealed that cashewnut shell liquid has no tumour initiating potency at a concentration of 10% (in 0.2 ml acetone) while it may act as weak promoter (P < 0.05) at a concentration of 5% (in 0.2 ml acetone). Testing for cocarcinogenic potency of cashewnut shell liquid (2% and 5% in 0.2 ml acetone) demonstrated that it has no cocarcinogenic potency on mouse skin tumour model when applied along with 2 x 10(-6)% benzo(a)pyrene in acetone up to a period of 20 weeks.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Anacardic Acids; Animals; Carcinogenicity Tests; Carcinogens; Cocarcinogenesis; Female; Mice; Mutagenicity Tests; Neoplasms, Experimental; Plant Extracts; Plants, Toxic; Resorcinols; Salicylates; Salmonella typhimurium; Skin Neoplasms

The ability of a biomimetic superoxide dismutase agent, copper(II)(3,5-diisopropylsalicylate)2 (CuDIPS), to modulate benzoyl peroxide (BzPo)-induced tumor promotion and progression in mouse skin multistage carcinogenesis was evaluated. The results showed a significant inhibition of tumor incidence by CuDIPS pretreatment during promotion-progression. Different types of tumors were developed: papillomas, keratoacanthomas and squamous cell carcinomas. There was a significant increase in the keratoacanthoma-papilloma ratio when the period of treatment with BzPo was prolonged, which was inhibited by CuDIPS pretreatment. CuDIPS induced a significant inhibition of malignant conversion. Our results suggest that reactive oxygen species could be important in BzPo-induced promotion and progression.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Antineoplastic Agents; Benzoyl Peroxide; Carcinoma, Squamous Cell; Cocarcinogenesis; Female; Incidence; Keratoacanthoma; Mice; Papilloma; Salicylates; Skin Neoplasms

Cu(II) (3,5-diisopropyl salicylate)2 (CuDIPS) which is an anti-inflammatory copper coordination compound (mol. wt. 503) possessing superoxide dismutase (SOD) activity was tested to determine its effect on 7,12-dimethylbenz[a]anthracene (DMBA)-induced initiation of tumors in mouse skin and on mutagenicity to 6-thioguanine resistance in a mouse keratinocyte mediated Chinese hamster V-79 cell system. A single application of CuDIPS (0.4 mg/mouse) administered at a short interval before DMBA application when followed by 20 weeks of promotion by TPA reduced the mouse skin tumor yield by 55%. When DMBA-induced cell-mediated mutagenesis was tested in the presence of CuDIPS a significant reduction in the number of V-79 6-thioguanine resistant mutants was observed.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Benz(a)Anthracenes; Biotransformation; Cocarcinogenesis; Cricetinae; Female; Mice; Salicylates; Skin Neoplasms