Pumping the Brakes on Pulmonary Fibrosis: A New Role for Regulator of Cell Cycle

Penke et al discuss the study by Luzina and colleagues on protein RGCC (regulator of cell cycle) which is a novel suppressor of fibrotic signaling in fibroblasts. The authors demonstrate that expression of RGCC in whole lung tissue isolated from both murine models of pulmonary fibrosis and patients with IPF was decreased when compared with normal, donor controls. Although RGCC is expressed in various cells throughout the lung, the decrease in fibroblasts was most pronounced, leading the investigators to focus on the role of this protein in that cell population. Interestingly, mice deficient in RGCC had paradoxical reactions to bleomycin-induced pulmonary fibrosis with reduced collagen production when challenged with one dose of bleomycin and elevated collagen when challenged with multiple doses, inducing a chronic fibrotic model.