Retrospective Study on the Effect of Adipose-Derived Stem Cells on the Proliferation and Apoptosis of Keloid Fibroblasts Through the Suppression of ITGA2

Background: Keloid is characterized by excessive collagen accumulation and fibroblast growth, which are fibroproliferative disorders of injured skin, causing functional limitations. Studies have shown that adiposederived stem cells (ADSCs) inhibit the bioactivity and fibrosis of keloid fibroblasts. However, the molecular mechanism of this effect of ADSCs on keloid formation has not been fully elucidated. Methods: This in vitro study used fibroblasts obtained from keloids. A consensus gene co-expression network was constructed to focus on identifying consensus gene co-expression modules associated with keloid fibroblasts. Differentially expressed genes (DEGs) were identified between keloid fibroblasts and normal dermal fibroblasts. A functional enrichment analysis was also performed with the DAVID database. A weighted gene co-expression network analysis (WGCNA) was used to screen keloid-related modules using the "WGCNA" R package, followed by hub gene selection in modules from the Protein-protein interaction network through the STRING database. Keloid fibroblasts and ADSCs were extracted and cultured. Proliferation and apoptosis were examined using a 5-ethynyl-2-deoxyuridine (Edu) kit and flow cytometry. Results: We identified 302 DEGs overlapping with a consensus analysis of clusters and a differential expression analysis between keloid fibroblasts and normal dermal fibroblasts. Most of these were involved in collagen binding, extracellular matrix organization, and the PI3K-Akt signaling pathway. WGCNA analysis selected a keloid-associated brown module. ITGA2 was identified as a novel marker in hub genes from the PPI network based on the degree and function of collagen modulation. Furthermore, the proliferation ability of keloid fibroblasts cultured in ADSC medium was inhibited while apoptosis was dramatically increased. Overexpression of ITGA2 reversed the decrease in ADSC-induced apoptosis and increased ADSC-reduced proliferation. Conclusion: Our study demonstrated that activation of ITGA2 plays a crucial role in ADSC-induced keloid fibroblast apoptosis and anti-proliferation effects. These results also improved our understanding of the molecular mechanism of the pathogenesis of keloid in response to ADSCs and may contribute to the further development of keloid therapy.