The value of dysregulated miR-4492/TRAF6 in diagnosis and prognosis for patients with community-acquired pneumonia

Community-acquired pneumonia (CAP) poses a serious threat to the lives of adults. Differentially expressed miRNAs play a crucial regulatory role in CAP. This study aims to explore the diagnostic and prognostic significance of miR-4492 in CAP and its possible mechanism of action with tumor necrosis factor receptor-associated factor 6 (TRAF6) in human bronchial epithelial cells (HBEpCs). Differentially expressed miRNAs were screened from the GSE196399 dataset, and miR-4492 levels were collected and detected in the serum of CAP patients. The diagnostic and prognostic value of miR-4492 was evaluated using receiver operating characteristic (ROC) curve, Kaplan-Meier survival analysis, and multivariate Cox regression model. miR-4492-TRAF6 interaction was validated via dual-luciferase assays and Pearson correlation. Cell viability and inflammatory factor concentrations were assessed using the CCK-8 assay and ELISA. miR-4492 was downregulated in the serum of CAP patients. ROC analysis demonstrated that miR-4492 distinguished the CAP patients from healthy controls, and its expression was negatively correlated with the CURB-65 score severity. Low miR-4492 level was a predictor of poor prognosis in CAP. TRAF6 was the target gene of miR-4492. LPS inhibited the expression level of miR-4492 and cell viability, and promoted the expression of TRAF6 and inflammation in HBEpCs. Overexpression of miR-4492 enhanced cell viability and suppressed the inflammatory response of HBEpCs, while overexpression of TRAF6 partly reversed the effect of miR-4492. In conclusion, low serum miR-4492 serves as a diagnostic and prognostic biomarker for CAP. miR-4492 mitigated LPS-induced inflammation and cell damage in HBEpCs by targeting TRAF6.