Matrix Metalloproteinase-9 as a Potential Biomarker in 631 Human Implant-Induced Fibrotic Capsules: Analysis and Biomarker Study

Background:Capsular fibrosis (CF) often occurs around biomedical devices following implantation causing pain, discomfort, and device failure. Breast implantation remains among the most common medical procedures worldwide. Revealing specific genes that drive fibrotic deposition will help us to garner a better understanding of the pathophysiology of this disease and develop different strategies to combat it.Methods:The authors collected 631 capsules around breast implants and were able to connect clinical baseline characteristics with histopathologic findings. In addition, the authors were able to conduct the first large systematic analysis to identify differentially expressed genes in fibrotic human tissue samples, comparing the lowest form of fibrosis with the most aggravated one.Results:The authors identified 2559 differentially expressed genes on which they performed a knowledge-based network generation and pathway association study to identify putative novel biomarkers for CF. The authors were able to show changes of cellular influx during progression of CF and distinguish several genes as potential clinical biomarkers and drug targets. Among these, matrix metalloproteinase-9 was one of the most up-regulated (P = 0.006) and is attractive because of its wide detectability.Conclusions:Matrix metalloproteinase-9 seems to be a potential biomarker to detect capsular fibrosis. It is a measurable indicator that can easily be detected in blood, sputum, and urine. For the diagnosis of fibrosis, this biomarker might be exceedingly beneficial to developing novel screening methods and prophylaxes.Clinical Relevance Statement:Discovering biomarkers at the earliest and mildest stages for the diagnosis of fibrosis is clinically important. These results bring new hope for biomarker-based diagnosis for capsular fibrosis.CLINICAL QUESTION/LEVEL OF EVIDENCE:Diagnostic, V.