Abstract
Fibrotic diseases remain a major cause of morbidity and mortality, yet there are few effective therapies. The underlying pathology of all fibrotic conditions is the activity of myofibroblasts. Using cells from freshly excised disease tissue from patients with Dupuytren's disease (DD), a localized fibrotic disorder of the palm, we sought to identify new therapeutic targets for fibrotic disease. We hypothesized that the persistent activity of myofibroblasts in fibrotic diseases might involve epigenetic modifications. Using a validated genetics-led target prioritization algorithm (Pi) of genome wide association studies (GWAS) data and a broad screen of epigenetic inhibitors, we found that the acetyltransferase CREBBP/EP300 is a major regulator of contractility and extracellular matrix production via control of H3K27 acetylation at the profibrotic genes, ACTA2 and COL1A1 Genomic analysis revealed that EP300 is highly enriched at enhancers associated with genes involved in multiple profibrotic pathways, and broad transcriptomic and proteomic profiling of CREBBP/EP300 inhibition by the chemical probe SGC-CBP30 identified collagen VI (Col VI) as a prominent downstream regulator of myofibroblast activity. Targeted Col VI knockdown results in significant decrease in profibrotic functions, including myofibroblast contractile force, extracellular matrix (ECM) production, chemotaxis, and wound healing. Further evidence for Col VI as a major determinant of fibrosis is its abundant expression within Dupuytren's nodules and also in the fibrotic foci of idiopathic pulmonary fibrosis (IPF). Thus, Col VI may represent a tractable therapeutic target across a range of fibrotic disorders.
Highlights
Using a validated genetics-led target prioritization algorithm (Pi) of genome wide association studies (GWAS) data and a broad screen of epigenetic inhibitors, we found that the acetyltransferase CREBBP/EP300 is a major regulator of contractility and extracellular matrix production via control of H3K27 acetylation at the profibrotic genes, ACTA2 and COL1A1
To leverage the power of genetic variance in target discovery, we applied our recently developed prioritization “Pi” approach [21] to risk loci in Dupuytren’s disease (DD) GWAS data [12]. This validated approach allows us to prioritize genes from GWAS hits, not based on genomic proximity and including evidence from chromatin conformation and expression quantative trait loci mapping in immune cells, plus gene networks defined by the Search Tool for the Retrieval of Interacting Genes/Proteins database. This unsupervised network connectivity analysis identified FoxO and WNT signaling as highly ranked pathways that share CREBBP and EP300 member genes, as shown at the intersection of delineated pathways in blue and green, respectively (Fig. 1A and SI Appendix, Table S1), providing unbiased support for our hypothesis that epigenetic modulators are important in controlling disease processes in DD
We screened a focused library of 39 epigenetic inhibitors (SI Appendix, Table S2) to study their effect on the expression of key profibrotic genes (ACTA2, COL1A1, COL3A1, and TGFB1) on early passage myofibroblasts derived from nodules in patients with DD (Fig. 1B and SI Appendix, Fig. S1)
Summary
Genomic analysis revealed that EP300 is highly enriched at enhancers associated with genes involved in multiple profibrotic pathways, and broad transcriptomic and proteomic profiling of CREBBP/EP300 inhibition by the chemical probe SGC-CBP30 identified collagen VI (Col VI) as a prominent downstream regulator of myofibroblast activity. Targeted Col VI knockdown results in significant decrease in profibrotic functions, including myofibroblast contractile force, extracellular matrix (ECM) production, chemotaxis, and wound healing. We utilize Dupuytren’s disease (DD), a common localized fibrotic disorder, to evaluate the impact of epigenetic regulation of myofibroblasts and identify potential tractable targets in human fibrosis. We identify collagen VI to be a key downstream target of CREBBP/EP300 and reveal valuable insights in the role it plays in key profibrotic functions, including contractile force, chemotaxis, and wound healing, and its potential as a therapeutic target
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
