(058) Evaluation of Pathway Expression Following Down-Regulation of NELL1, a Potential Gene of Interest in Peyronie’s Disease

Abstract

Abstract Introduction Peyronie’s Disease (PD) is a superficial fibrosing disorder characterized by inelastic fibrous plaques within the tunica albuginea. We previously performed high-resolution array comparative genomic hybridization analysis of genomic DNA from men with both PD and Dupuytren’s Disease (DD), yielding candidate genes, including NELL1, with potential involvement in these conditions. NELL1 is a secreted growth factor that enhances osteoblastic differentiation and chondrogenesis and may contribute to calcification and inflammation in fibrotic plaques via its interaction with bone morphogenetic protein (BMP) within the TGF-β signaling pathway. Here, we report on pathway analysis following up- and down-regulation of NELL1 using CRISPR modification in an in vitro setting. Objective This study aimed to investigate the influence of NELL1 modification on downstream gene regulation, focusing on pathways that were significantly regulated following NELL1 down-regulation. Methods For down-regulation of NELL1, gRNAs were delivered to HEK293 cells with a nuclease deficient (d) dCas9-KRAB system adapted from Streptococcus pyogenes. Gene regulation was assessed using qRT-PCR. Results For down-regulation of NELL1, PCR analysis confirmed a 95% reduction in expression. Non-target vectors did not change NELL1 expression levels. RNA sequencing results found over 5,000 differentially expressed genes between, with significant changes in multiple pathways, including the HIF-1α pathway, which promotes keloid development by activating the TGF-β/Smad pathways. Additionally, we identified pathways related to ECM-receptor interaction, inflammation, apoptosis, and cell cycle regulation that are mediated by TGF-β/Smad signaling, which plays a crucial role in fibrosis. Our analysis also demonstrated upregulation of the PI3K-Akt pathway, which is involved in regulating type I collagen expression in response to TGF-β1. These results highlight the significance of NELL1 in fibrotic regulation and suggest its potential involvement in the development of PD. Conclusions We have created guides for and successfully down-regulated the expression of NELL1, a gene of interest in Peyronie’s disease. We have also demonstrated, through RNA sequencing, that changes in NELL1 lead to large changes in gene and pathway expression. The identified modified pathways, including HIF-1α-mediated, TGF-β/Smad and PI3K-Akt, provide valuable insights into the potential molecular mechanisms underlying NELL1's role in regulation of fibrosis, and further investigation of these pathways may reveal potential therapeutic targets for fibrosis-related disorders. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Contraline, Techfields Inc, Alto Neurosciences, Curebase.