Inhibition of Metastatic Squamous Cell Carcinoma Development in Protein Kinase C Epsilon Transgenic Mice by Alpha-Difluoromethylornithine with Hair Follicle Degeneration and Hair Loss

The study investigated the effects of TPA-stimulated polyamine biosynthesis on metastatic squamous cell carcinoma (mSCC) development in protein kinase C epsilon (PKC epsilon) transgenic mice. It was found that TPA treatment significantly increased epidermal ornithine decarboxylase (ODC) activity and putrescine levels in these mice compared to wild-type littermates. The development of mSCC was completely prevented by administering alpha-difluoromethylornithine (DFMO), an ODC inhibitor, in the drinking water during TPA promotion. However, this treatment resulted in marked hair loss and a decrease in intact hair follicles in the transgenic mice. The findings suggested a link between TPA-induced ODC activity, putrescine accumulation, hair follicle maintenance, and mSCC development, with the observed hair loss being a novel side effect not previously reported in other cancer prevention models.