The PLCG2 Inhibits Tumor Progression and Mediates Angiogenesis by VEGF Signaling Pathway in Clear Cell Renal Cell Carcinoma.

Abstract

Background: Clear cell renal cell carcinoma (ccRCC) represents the most prevalent form of renal cell carcinoma. The management of early-stage ccRCC has a better prognosis, while patients with metastatic ccRCC have a lower five-year survival rate. Angiogenesis serves as the fundamental process underlying tumor metastasis. Therefore, it is crucial to discover new targets for angiogenesis to improve patient survival rates.

Methods: The Cancer Genome Atlas database, International Cancer Genome Consortium database, Clinical Proteomic Tumor Analysis Consortium database, and a gene set of the vascular endothelial growth factor (VEGF) signaling pathway were utilized to identify differentially expressed genes. Western blot (WB), quantitative real-time polymerase chain reaction, and immunohistochemistry were employed to validate the downregulation of phospholipase C gamma 2 (PLCG2) in ccRCC tissues and cells. Cell Counting Kit-8 (CCK-8) assays, transwell assays, tube formation assays, and oil-red staining were performed to elucidate the biological functions of PLCG2 in tumor cells. Gene set enrichment analysis was applied to explore the downstream pathway. Subcutaneous tumor models and live small animal fluorescent imaging assay were utilized for in vivo investigation of the roles played by PLCG2.

Results: Our study has identified a novel biomarker, PLCG2, for ccRCC. PLCG2 is a central gene in regulating angiogenesis in ccRCC, as validated by bioinformatics analysis. The findings revealed a diminished expression of PLCG2 in both ccRCC tissues and cells. Further experiments in vivo and in vitro have demonstrated the significant roles of PLCG2 in tumor proliferation, invasion, migration, and lipid accumulation. Results of tube formation assays and WB support the role of PLCG2 in regulating VEGFA expression and angiogenesis.

Conclusions: Our results show that PLCG2 functions as a potential biomarker and an independent prognostic indicator for ccRCC. PLCG2 may modulate angiogenesis by influencing the expression of VEGFA. Therefore, targeting PLCG2 could potentially lead to drug discovery and improved cancer treatment strategies.