Role of Alkaline Ceramidase 1 in Regulating Epidermal Homeostasis and Tumorigenesis

The study investigated the role of alkaline ceramidase 1 (Acer1) in epidermal homeostasis and tumorigenesis using a mouse model deficient in the Acer1 gene. It was found that Acer1 is crucial for regulating the proliferation and differentiation of epidermal keratinocytes by controlling ceramide metabolism. Loss of Acer1 led to elevated ceramide levels, progressive hair loss, and widened follicular infundibulum due to reduced survival and stemness of hair follicle stem cells (HFSC). Additionally, Acer1 deficiency protected mice from chemical and UVB-induced skin carcinogenesis, suggesting its role in maintaining hair follicle structure and function and regulating skin tumorigenesis by controlling tumor-initiating cells.