TY - JOUR AU - Clocchiatti, Andrea AU - Ghosh, Soumitra AU - Procopio, Maria-Giuseppina AU - Mazzeo, Luigi AU - Bordignon, Pino AU - Ostano, Paola AU - Goruppi, Sandro AU - Bottoni, Giulia AU - Katarkar, Atul AU - Levesque, Mitchell AU - Kölblinger, Peter AU - Dummer, Reinhard AU - Neel, Victor AU - Özdemir, Berna C. AU - Dotto, G. Paolo T1 - Androgen receptor functions as transcriptional repressor of cancer-associated fibroblast activation PY - 2018/12/03/ AB - The aging-associated increase of cancer risk is linked with stromal fibroblast senescence and concomitant cancer-associated fibroblast (CAF) activation. Surprisingly little is known about the role of androgen receptor (AR) signaling in this context. We have found downmodulated AR expression in dermal fibroblasts underlying premalignant skin cancer lesions (actinic keratoses and dysplastic nevi) as well as in CAFs from the 3 major skin cancer types, squamous cell carcinomas (SCCs), basal cell carcinomas, and melanomas. Functionally, decreased AR expression in primary human dermal fibroblasts (HDFs) from multiple individuals induced early steps of CAF activation, and in an orthotopic skin cancer model, AR loss in HDFs enhanced tumorigenicity of SCC and melanoma cells. Forming a complex, AR converged with CSL/RBP-Jκ in transcriptional repression of key CAF effector genes. AR and CSL were positive determinants of each other’s expression, with BET inhibitors, which counteract the effects of decreased CSL, restoring AR expression and activity in CAFs. Increased AR expression in these cells overcame the consequences of CSL loss and was by itself sufficient to block the growth and tumor-enhancing effects of CAFs on neighboring cancer cells. As such, the findings establish AR as a target for stroma-focused cancer chemoprevention and treatment. JF - The Journal of Clinical Investigation JA - J Clin Invest SN - 0021-9738 DO - 10.1172/JCI99159 VL - 128 IS - 12 UR - https://doi.org/10.1172/JCI99159 SP - 5531 EP - 5548 PB - The American Society for Clinical Investigation ER -