IL-7R Expression Correlates with Prognosis in Breast Cancer

Background: The tumor microenvironment (TME) exerts a significant influence on the development, invasion, metastasis, and drug resistance of breast cancer. Therefore, this study sought to investigate potential prognostic factors and markers indicative of TME remodeling in breast cancer, utilizing data from the TCGA database. Methods: In this study, transcriptome RNA-seq data from 1222 breast cancer samples were processed using CIBERSORT and ESTIMATE algorithms. We conducted a differential gene expression analysis utilizing COX regression analysis and constructed protein-protein interaction (PPI) networks for enhanced visualization. Through univariate COX analysis and cross-analysis within PPI networks, the Interleukin-7 receptor (IL-7R) emerged as a potential predictor. Subsequently, we performed a comprehensive investigation encompassing single-gene survival analysis, clinical correlation assessment, and GSEA enrichment analysis targeting IL-7R as a core gene associated with prognosis. We examined the expression of IL-7R in human breast cancer and normal breast tissue through clinical studies and cytology experiments, followed by an indepth analysis of the relationship between IL-7R and breast cancer. Results: The survival analysis revealed that breast cancer patients with elevated IL-7R expression experienced prolonged survival compared to those with lower IL-7R levels. Results obtained from the Wilcoxon rank-sum test, along with clinical and cellular experiments, indicated higher IL-7R expression in tumor samples compared to normal samples. Correlation tests conducted between IL-7R expression and clinicopathological stage characteristics highlighted statistically significant associations between IL-7R expression and the T and M stages. Additionally, cell classification analysis of tumor-infiltrating immune cells (TIC) proportion showed that activated CD4+ T cells and CD8 T cells of memory B cells were positively correlated with IL-7R expression. These findings further underscored the impact of IL-7R levels on the tumor microenvironment (TME). Conclusion: IL-7R emerges as a potential prognostic indicator for breast cancer patients, particularly in sustaining the immunoactive status of the tumor microenvironment (TME) and contributing to immune reconstitution. These findings offer novel insights into breast cancer treatment strategies.