Regular Articles Fas Signaling Is Involved in the Control of Hair Follicle Response to Chemotherapy Andrei A. Sharov1, Frank Siebenhaar1,2, Tatyana Y. Sharova1, Natalia V. Botchkareva1, Barbara A. Gilchrest1 and Vladimir A. Botchkarev1 1 Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts; and 2 Department of Dermatology, Johannes Gutenberg-University, Mainz, Germany Chemotherapeutic agents induce p53-dependent apoptosis in the hair follicle (HF) resulting in hair loss, a common side effect of cancer therapy. Here, we show that Fas as a p53 target plays important role in the HF response to cyclophosphamide. Specifically, we demonstrate that Fas is up-regulated in HF keratinocytes after cyclophosphamide treatment, Fas ligand–neutralizing antibody partially inhibits HF response to cyclophosphamide in wild-type mice, and Fas knockout mice show significant retardation of cyclophosphamide-induced HF involution associated with reduced Fas-associated death domain and caspase-8 expression. These data raise a possibility to explore blockade of Fas signaling as a part of complex local therapy for inhibiting keratinocyte apoptosis and hair loss induced by chemotherapy. Cancer Research 64, 6266-6270, September 1, 2004 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.