ASAH1 and cancer: Previous studies by other groups demonstrated that DNA damaging agents also increase the expression of the acid ceramidase gene (ASHA1) [27, 40, 41] or transiently increase its activity in certain cancer cell lines through a post-translational modification [26] whereas Uchida et al. [29] showed that DNA damage by ultraviolet radiation (UVR) decreases ASHA1 and ASHA2 (the neutral ceramidase) activity in epidermal keratinocytes.