Leukotriene B4 receptor 2 correlates with prognosis and immune infiltration in clear cell renal cell carcinoma.

Background: Clear cell renal cell carcinoma (ccRCC) is the most common renal cancer. According to reports, leukotriene B4 receptor 2 (LTB4R2, also known as BLT2), a chemokine receptor, is upregulated in different tumors. However, the correlation between BLT2 expression and its prognostic value in ccRCC remains to be explored.
Methods: This study used the The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases to evaluate the association between BLT2 expression and the clinical outcome of ccRCC. Based on TIMER2.0, the correlation between BLT2 expression in ccRCC and tumor immune characteristics was evaluated.
Results: The expression of BLT2 in ccRCC was higher than that in 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, our findings revealed that there was no significant correlation between the M1 marker genes and the expression of BLT2 in ccRCC, while moderate correlations were observed between the BLT2 expression and the M2 marker genes. Tregs and T cell exhaustion marker genes were positively correlated with BLT2 expression in ccRCC (p < 0.001).
Conclusion: BLT2 may serve as a novel prognostic biomarker and is related to the shaping of tumor immune microenvironment in ccRCC. The expression of BLT2 potentially contributes to the regulation of TAMs, T cell exhaustion, and Tregs activation in ccRCC, providing new approaches to promote the development of new immunotherapeutic strategies for ccRCC.
(© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)