Inhibition of methylcholanthrene-induced skin carcinogenesis in hairless mice by the membrane-labilizing agent DMSO.

The effects of dimethyl sulphoxide (DMSO) are in some respects similar to those of retinoids. DMSO has the ability to penetrate cellular membranes and to enhance the penetration of other molecules. It may be reasonable to assume that DMSO treatment results in differentiation of cells, possibly through membrane-mediated events. This may be of importance for the study of the carcinogenic process. The release of a certain amount of lysosomal enzymes to the extracellular space is a normal function of the cell (Hickman & Neufeld, 1972), and a certain release of the cytoplasmic and lysosomal enzymes to the extracellular space is not necessarily deleterious for the cells (Volden, Haugen & Skrede, 1980). The purpose of the present investigation was to study the possible effects of DMSO on methylcholanthrene-induced skin carcinogenesis. Since the uptake of lysosomal enzymes by cultured cells appears to involve a membrane receptor process, the effects of the carcinogen and the solvents on the rate of secretion of lysosomal enzymes and lactate dehydrogenase from HeLa cells were investigated.