Identification and histological validation of autophagy-related core genes ADRB2 and PLK2 in keloids, with integrated immune infiltration analysis

Introduction: Keloids are pathological fibroproliferative scars characterized by excessive collagen deposition and a lack of effective targeted therapies. Autophagy dysregulation has been linked to keloid pathogenesis, but the underlying molecular mechanisms remain unclear. Methods: Transcriptomic datasets were integrated and analyzed using differential expression analysis and weighted gene co-expression network analysis. Three machine learning algorithms-least absolute shrinkage and selection operator (LASSO), support vector machine-recursive feature elimination (SVM-RFE), and random forest-were applied to identify autophagy-related hub gene candidates in keloids. Immune infiltration and functional analyses were conducted to explore immune microenvironment alterations. Histological staining (H&E and Masson), immunohistochemistry, and Western blotting were used for tissue-level validation, while cellular experiments were performed in keloid fibroblasts with autophagy modulation. Results: ADRB2 and PLK2 were consistently identified as key autophagy-related candidate genes. Immune-related analyses suggested that these genes may be involved in remodeling the keloid immune microenvironment by influencing the abundance and functional status of multiple immune cell subsets. Histological and protein-level assays demonstrated significantly higher expression of ADRB2 and PLK2 in keloid tissues compared with adjacent normal skin. In keloid fibroblasts, fibrotic markers (COL1/COL3) and autophagy-related markers (LC3-II/LC3-I and p62) were upregulated concomitantly with ADRB2 and PLK2 at baseline. Autophagy modulation altered ADRB2 expression (decreased with EBSS and increased with chloroquine), whereas PLK2 expression remained largely unchanged. Discussion: These findings identify ADRB2 and PLK2 as under-recognized autophagy- andimmunity-related candidate biomarkers in keloids, highlighting their potential relevance asdiagnostic indicators and future therapeutic research targets.