Neutrophil extracellular traps promote clear cell renal cell carcinoma progression via TGFβ1-pSmad2-MMP9 signaling

Methods

The formation of NETs was evaluated in clinical ccRCC tissue samples and patient plasma using immunohistochemistry, immunofluorescence, and ELISA. The impacts of NETs on ccRCC cell proliferation, apoptosis, migration, and invasion were investigated through both in vitro and in vivo experimental models. To elucidate the molecular mechanisms, RNA sequencing, database analysis, chromatin immunoprecipitation (ChIP), luciferase reporter assays, and pharmacological inhibitors (DNase I and JNJ-0966) were employed.

Results: NETs levels were markedly elevated in patients with ccRCC, particularly in those with metastatic disease. NETs were found to promote ccRCC cell proliferation, inhibit apoptosis, and enhance migratory and invasive capabilities by activating the TGFβ1-pSmad2 signaling pathway, which subsequently led to the transcriptional upregulation of MMP9. Clinical data revealed that overexpression of TGFβ1 and MMP9 was associated with poorer overall survival.

In vivo studies demonstrated that degradation of NETs with DNase I or inhibition of MMP9 with JNJ-0966 significantly attenuated tumor metastasis. Conclusions: NETs contribute to ccRCC progression through the TGFβ1-pSmad2- MMP9 signaling axis. Targeting NETs or their downstream effector, MMP9, may offer a promising therapeutic approach for the treatment of advanced ccRCC.