Tumor microenvironmental prognosis analysis and molecular labeling of immune-related genes in Luminal B type breast cancer

Background: Tumor microenvironment (TME) cells is one of the important elements, constitute the tumor tissues and in predicting tumor clinical results and treatment effect has the important significance of clinical pathology. However, a detailed map for prognostic landscape of TME in Luminal B breast cancer is still lacking. Methods: ownloaded the expression profile and clinical follow-up information of luminal B breast cancer from TCGA and GEO, and used CIBERSORT to evaluate the infiltration mode of TME in 209 patients, and constructed the molecular subtype of luminal B breast cancer based on TME, further evaluated the relationship between molecular subtype and prognosis. DESeq2 was used to analyze the differentially expressed genes among molecular subtypes of luminal B breast cancer, and cox multivariate regression analysis was used for feature selection to construct TME signature. Results: ased on the median value of TMEscore, the samples were divided into High TMEscore and Low TMEscroe, and the relationship with prognosis, clinical features, immune gene expression and genomic variation was further evaluated. Different TME cells have significant correlation in luminal B breast cancer. These TME cells stratified different clinical results of luminal B breast cancer, and further TMEscore was established by Cox regression analysis. High TME score is associated with poor prognosis. Meanwhile, this study showed that CXCL10, CXCL9, GZMB and other immune activation genes and PDCD1LG2 and other immune checkpoint genes have higher expression levels in high TME score, and the mutation frequency of TP53 gene was lower in risk-H than that in risk-L. Conclusion: In this study, we systematically evaluated the TME infiltration patterns of 209 TCGA luminal B breast cancer patients and developed the TME score approach. It was found that TME score is a powerful prognostic biomarker and predictor of response to immunocheckpoint inhibitors and provides a new strategy for luminal B breast cancer immunotherapy.