Comprehensive Analysis of Clinical Prognosis and Molecular Characteristics of LTB4R2 in Clear Cell Renal Cell Carcinoma

Background: Clear cell renal cell carcinoma (ccRCC) is the most common renal cancer. LTB4 receptor 2 (LTB4R2, also called BLT2), as a chemokine receptor, has been reported to be upregulated in different tumors and associated with tumor cell proliferation and invasion. However, the correlation between BLT2 expression and its prognostic value in ccRCC remain to be explored.MethodsWe used the TCGA and GEO databases to evaluate the association between BLT2 expression and clinical outcome of ccRCC. The top 300 genes that most positively correlated with BLT2 were selected for functional enrichment analysis. Correlations between BLT2 expression and tumor immune characteristics in ccRCC were evaluated based on TIMER2.0.ResultsBLT2 expression was higher in ccRCC than normal tissues. Kaplan-Meier survival analysis indicated that high BLT2 expression was significantly correlated with poor overall survival (HR = 1.75, p＜0.001) and disease-specific survival (HR = 1.60, p＝0.014) for patients with ccRCC. In addition, the findings revealed that M1 marker genes had no significant correlations with BLT2 expression in ccRCC, while moderate correlations were observed between BLT2 expression and M2 marker genes. The marker genes of Tregs and T cell exhaustion positively correlated with BLT2 expression in ccRCC (p＜0.001). ConclusionBLT2 may serve as a novel prognostic biomarker and correlate with tumor immune microenvironment shaping in ccRCC. BLT2 expression potentially contributes to the regulation of TAMs, T cell exhaustion, and Tregs activation in ccRCC, providing new approaches to drive the development of new immunotherapeutic strategies for ccRCC.