Analysis of Potential Genetic Biomarkers Using Machine Learning Methods and Immune Infiltration Regulatory Mechanisms Underlying Atrial Fibrillation Running Title: Identification of Biomarkers for Af via Machine Learning
Abstract Objective: We aimed to screen out biomarkers for atrial fibrillation (AF) based on machine learning methods and evaluate the degree of immune infiltration in AF patients in detail.Methods: Two datasets (GSE41177 and GSE79768) related to AF in GEO database were included. Differentially expressed genes (DEGs) were screened out using “limma” package. Candidate biomarkers for AF were identified using machine learning methods of the LASSO regression algorithm and SVM-RFE algorithm. Receiver operating characteristic (ROC) curve was employed to assess the diagnostic effectiveness of biomarkers, which was further validated in the GSE14795 dataset. Moreover, we used CIBERSORT to study the proportion of infiltrating immune cells in each sample, and the Spearman method was used to explore the correlation between biomarkers and immune cells.Results: 129 DEGs were identified, and CYBB, CXCR2, and S100A4 were identified as key biomarkers of AF using LASSO regression and SVM-RFE algorithm, and the diagnostic value was further validated in GSE14795. Immune infiltration analysis indicated that, compared with sinus rhythm (SR), the atrial samples of patients with AF contained a higher T cells gamma delta, neutrophils and mast cells resting, whereas T cells follicular helper were relatively lower. Correlation analysis demonstrated that CYBB, CXCR2, and S100A4 were significantly correlated with the infiltrating immune cells.Conclusions: In conclusion, this study suggested that CYBB, CXCR2, and S100A4 are key biomarkers correlated with infiltrating immune cells in AF, and infiltrating immune cells play pivotal roles in AF.