Succinic dehydrogenase and cytochrome oxidase in epidermal carcinogenesis induced by methylcholanthrene in mice.

The role of the alkalies, alkaline earths, and of iron, copper, and zinc in epidermal carcinogenesis in mice has been described (4) and the integration of the chemical, physical, and histological changes in mouse epidermis undergoing carcinogenesis has been reviewed by Cowdry (7). The investigations on the minerals revealed that the calcium, iron, zinc, and copper contents of hyperplastlc (methylcholanthrene-treated) epidermis were significantly less than that of normal epidermis, and furthermore the content of these metals in the squamous cell carcinoma was reduced to even lower values. Since calcium may be associated with the succinic dehydrogenase system ( 15, 21, 27), and copper and iron with cytochrome oxidase (20), experimen:s were undertaken to study these enzymes in the epiderntis of mice under the carcinogenic influence of methylcholanthrene.