Exploration of CD2 and CD3D as potential immune-related biomarkers for IORT in breast cancer treatment

Breast cancer is a prevalent malignancy among women worldwide. Understanding its molecular mechanisms is crucial for prevention, early diagnosis, and treatment. Using a dataset of intraoperative radiotherapy (IORT) for breast cancer, we analyzed 21 breast tissue samples from patients who received IORT and 16 samples from those who did not. Principal component analysis was employed to reveal data structure, and differentially expressed genes (DEGs) were identified. We constructed a gene network using weighted gene co-expression network analysis and conducted functional enrichment analysis and gene set enrichment analysis. Immune infiltration analysis and protein-protein interaction network analysis were performed, resulting in gene expression heatmaps and Comparative Toxicogenomics Database analysis. Finally, regulatory microRNAs (miRNA) for core genes were predicted using miRNA prediction websites. A total of 2774 DEGs were identified. Principal component analysis demonstrated the differentiation between IORT and non-IORT samples. DEGs were enriched in key biological processes, such as T-cell receptor signaling, immunological synapse formation, and apoptosis. Gene set enrichment analysis validated the functional enrichment of DEGs. Weighted gene co-expression network analysis constructed 15 modules and identified hub genes. Protein-protein interaction network analysis revealed 4 core genes (CD2, CD3D, CD3G, and CD3E). miRNA prediction identified regulatory miRNAs for these core genes. Comparative Toxicogenomics Database analysis revealed that these core genes are associated with breast tumors and inflammation. Immune infiltration analysis showed a high proportion of Macrophages M0 and Macrophages M2 in the samples and revealed correlations between T cells and neutrophils. These findings suggest that the core genes may play key roles in the pathological changes and immune regulation of breast cancer tissues. CD2 and CD3D may serve as potential immune-related biomarkers for IORT in the treatment of breast cancer, influencing tissue pathological changes in breast cancer patients by regulating immune responses and cell signaling pathways.