A Combined Bioinformatics and Clinical Validation Approach Identifies CEACAM1 and RRAS2 as Key SASP-Related Biomarkers in Neuropathic Pain

Background: Neuropathic pain (NP) represents a persistent pain syndrome that develops following injury to or pathological alterations in the somatosensory pathways. Inflammatory signaling associated with cellular senescence has recently been proposed as an important factor in the development of NP. However, the precise molecular underpinnings of this relationship remain poorly defined. Methods: Differential gene expression analysis of the public dataset GSE150408 (dorsal root ganglia from a rodent neuropathic pain model) identified differentially expressed genes (DEGs). Candidate genes were identified through cross-referencing with the SASP gene collection documented in the SenMayo repository. Two computational approaches were employed for feature selection: the Least Absolute Shrinkage and Selection Operator (LASSO) regression model alongside Support Vector Machine-Recursive Feature Elimination (SVM-RFE) methodology, which collectively narrowed down the gene candidates. Subsequently, a comprehensive analytical framework was applied, which included constructing a diagnostic nomogram, performing gene set enrichment analysis (GSEA), profiling immune cell infiltration (via CIBERSORT), and conducting in silico drug prediction. Experimental verification of biomarker expression levels was conducted via quantitative reverse transcription polymerase chain reaction (RT-qPCR) analysis. The validation utilized peripheral blood mononuclear cells (PBMCs) obtained from an independent sample cohort consisting of five NP patients and five age-matched healthy individuals serving as controls. Between-group comparisons were performed through unpaired two-tailed Student's t-test to determine statistical significance. Results: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and Ras-related protein R-Ras2 (RRAS2) were identified as core SASP-related biomarkers for NP. A diagnostic nomogram incorporating these two genes exhibited strong discriminatory power, achieving an area under the curve (AUC) of 0.92. Subsequent experimental validation in human blood samples confirmed a significant upregulation of CEACAM1 and concomitant downregulation of RRAS2 in NP patients compared to healthy controls ( p <0.05), thereby corroborating our initial computational predictions. Conclusion: Combining computational biology with clinical validation, this study definitively identifies CEACAM1 and RRAS2 as robust SASP-associated biomarkers for NP. Our findings not only shed light on the intricate interplay between cellular senescence and neuroinflammation in NP pathogenesis but also provide a foundational framework for developing novel diagnostic strategies and targeted therapies. The identified biomarkers demonstrate considerable potential for enhancing diagnostic and therapeutic strategies in managing this clinically challenging condition.