PROMOTING ACTION OF CASHEW NUT SHELL OIL IN DMBA-INITIATED MOUSE SKIN TUMOR-MODEL SYSTEM

The commercially available oil derived from the shell of cashew nut (Anacardium occidentale) was tested for its potency in promoting the DMBA-initiated cells into papillomas in a murine two-stage skin tumorigenesis model system. Male Swiss albino mice (9 - 10-weeks-old) were assorted into different groups and treated topically with single sub-carcinogenic doses of DMBA (50-mu-g in 0.1 ml acetone) followed by application of 1 % and 2 % shell oil in acetone three times a week. Animals were sacrificed after 20 weeks from the commencement of the experiment. The results imply a weak tumour promoting effect of cashew nut shell oil as the mean tumour incidences were found to be 1.1 and 2.5 in 1 % and 2 % oil treatment groups, respectively, while the corresponding figure vas 6.6 in the positive control group (DMBA and 1 % croton oil in acetone). Few speculative mechanisms for the observed effect of cashew nut shell oil on initiated skin are discussed.