Increased skin papilloma formation in mice lacking the sterol reductase activity codified by the Tm7sf2 gene

Tm7sf2 gene encodes 3b-hydroxysterol D14-reductase, which catalyzes the reduction of C14 unsaturated intermediates in the post-squalene segment of cholesterol biosynthesis. Cholesterol and its derivative cholesterol sulphate (CS) play a significant role in the proper functioning of the
stratum corneum in the skin. CS inhibits the  promotional phase of skin carcinogenesis mediating epidermal keratinocytes differentiation and
markedly suppresses tumour formation. The two-stage skin carcinogenesis (DMBA/TPA) protocol
is a well-established method to investigate skin tumor formation in mice, which mimics the multistage nature of human cancer development.