Therapy for fibrotic diseases: nearing the starting line.

Fibrosis, or the accumulation of extracellular matrix molecules that make up scar tissue, is a common feature of chronic tissue injury. Pulmonary fibrosis, renal fibrosis, and hepatic cirrhosis are among the more common fibrotic diseases, which in aggregate represent a huge unmet clinical need. New appreciation of the common features of fibrosis that are conserved among tissues has led to a clearer understanding of how epithelial injury provokes dysregulation of cell differentiation, signaling, and protein secretion. At the same time, discovery of tissue-specific features of fibrogenesis, combined with insights about genetic regulation of fibrosis, has laid the groundwork for biomarker discovery and validation, and the rational identification of mechanism-based antifibrotic drugs. Together, these advances herald an era of sustained focus on translating the biology of fibrosis into meaningful improvements in quality and length of life in patients with chronic fibrosing diseases.