Temporal gene signature of myofibroblast transformation in Peyronie’s disease: first insights into the molecular mechanisms of irreversibility

Transformation of resident fibroblasts to pro-fibrotic myofibroblasts in the tunica albuginea is a critical step in the pathophysiology of Peyronie’s disease (PD). We have previously shown that myofibroblasts do not revert to fibroblast phenotype and suggested a point of no return at 36 hr after induction of the transformation. However, the molecular mechanisms that drive this proposed irreversibility are not known.

Aim: Identify molecular pathways that drive the irreversibility of myofibroblast transformation by analysing the expression of the genes involved in the process in a temporal fashion.

Methods: Human primary fibroblasts obtained from tunica albuginea of patients with Peyronie’s disease were transformed to myofibroblasts using TGF-β1. The mRNA of the cells was collected at 0, 24, 36, 48, and 72 hrs after stimulation with TGF-β1 and then analysed using Nanostring nCounter Fibrosis panel. The gene expression results were analysed using Reactome pathway analysis database and ANNi, a deep learning-based inference algorithm based on a swarm approach.

Outcomes: A time course of changes in gene expression during transformation of PD-derived fibroblasts to myofibroblasts.

Results: The temporal analysis of the gene expression revealed that the majority of the changes at gene expression level happened within the first 24 hours and remained so throughout the 72 hours period. At 36 hours, significant changes were observed in genes involved in MAPK-Hedgehog signalling pathways.

Clinical Translation: This study highlights the importance of early intervention in clinical management of PD and future potential of new drugs targeting the point of no return.

Strengths & Limitations: The use of human primary cells and confirmation of results with further RNA analysis are the strengths of this study. The study is limited to 760 genes rather than the whole transcriptome.

Conclusion: This is the first analysis of temporal gene expression associated with the regulation of the transformation of resident fibroblasts to pro-fibrotic myofibroblasts in PD. Further research is warranted to investigate the role of MAPK-Hedgehog signalling pathways in reversibility of PD.