TNF and renal fibrosis: Consistently, during the course of circUBXN7-induced renal fibrosis, we observed increasing inflammatory cytokines level of IL-6 and TNFα in macrophages cultured with HK-2 cells of circUBXN7 overexpression, suggesting macrophage activation might accelerate EMT and fibrosis HK-2 cells via inflammatory cytokines secretion.