title: Inhibition of methylcholanthrene-induced skin carcinogenesis in hairless mice by dimethyl sulfoxide.
abstract: Hairless mice were given 5 topical applications of 470 nmol 20-methylcholanthrene (MCA) at one week intervals. In one experimental group the MCA was dissolved in reagent grade acetone alone, in another group it was dissolved in a mixture consisting of 50% acetone and 50% dimethyl sulfoxide (DMSO). A control group received the mixed solvent alone. The animals were observed for development of papillomas and malignant tumors during 75 weeks. The group treated with MCA in acetone/DMSO had a higher mortality than the two other groups. The admixture of 50% DMSO to the solvent had a significant inhibitory effect on tumor and cancer rates and on cancer yield, whereas no effect could be observed on the tumor yield. Hence, 50% DMSO in the solvent has a moderate, but significant, inhibitor effect on MCA-induced skin carcinogenesis. Similar inhibitory effect of DMSO on the promotion phase in two stage-carcinogenesis protocols have been reported in the literature. The biochemical mechanisms behind this effect are unknown.
mesh_terms: D000818:Animals; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D005260:Female; D008297:Male; D008748:Methylcholanthrene / Q000037:antagonists & inhibitors*; D051379:Mice; D008812:Mice, Hairless; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000517:prevention & control; D012878:Skin Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D013997:Time Factors
chemical_list: D008748:Methylcholanthrene; D004121:Dimethyl Sulfoxide