ABSTRACT
Anti-double-stranded DNA (dsDNA) antibodies induce renal damage in patients with systemic lupus erythematosus by triggering fibrotic processes in kidney cells. However, the precise mechanism underlying penetration of anti-dsDNA immunoglubolin G (IgG) into cells remains unclear. This study was designed to investigate the effect of tumor necrosis factor-like weak inducer of apoptosis (TWEAK)/fibroblast growth factor inducible 14 (Fn14) signaling on anti-dsDNA IgG penetration into cells. Mesangial cells were cultured in vitro, and stimulated with TWEAK and anti-dsDNA IgG. The results revealed that TWEAK dose-dependently enhanced cellular internalization of anti-dsDNA IgG and the expression of high-mobility group box 1 (HMGB1). In addition, TWEAK and anti-dsDNA IgG synthetically downregulate suppressor of cytokine signaling 1, and induce the expression of various fibrotic factors. Furthermore, inhibition of HMGB1 attenuates the enhancement effect of TWEAK on anti-dsDNA IgG internalization. The TWEAK upregulation of HMGB1 involves the nuclear factor-κB and phosphatidylinositide 3-kinase/protein kinase B pathways. Therefore, TWEAK/Fn14 signaling contributes to the penetration of anti-dsDNA IgG and relevant fibrotic processes in mesangial cells.
Subject(s)
Antibodies/metabolism , DNA/metabolism , Mesangial Cells/metabolism , Signal Transduction/physiology , TWEAK Receptor/metabolism , Animals , Apoptosis/physiology , Down-Regulation/physiology , Fibrosis/metabolism , HMGB1 Protein/metabolism , Hep G2 Cells , Humans , Immunoglobulin G/metabolism , Kidney/metabolism , Mice , NF-kappa B/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Up-Regulation/physiologyABSTRACT
Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) engagement with the receptor Fn14 contributes to the fibrotic process of kidney cells in systemic lupus erythematosus. Downregulation of the protein suppressor of cytokine signaling 1 (SOCS1) correlates with amplified production of proinflammatory factors and cell apoptosis, which participate in the pathogenesis of lupus nephritis. To elucidate the potential role of SOCS1 in TWEAK/Fn14 signaling, we determined the SOCS1 levels in primary kidney cells from MRL/MpJ (control strain) or MRL/lpr (lupus-prone) mice. These cells (mesangial cells, glomerular endothelial cells, and tubular epithelial cells) were also evaluated after stimulation with TWEAK (0 to 250 ng/mL). The results showed that the lupus-prone cells exhibited reduced SOCS1 expression. TWEAK induced the production of profibrotic factors (laminin, fibronectin, (CC motif) ligand 20, etc.) in kidney cells from both mouse strains. TWEAK stimulation also decreased both the mRNA and protein levels of SOCS1 in all cells. Moreover, the effect of TWEAK on mesangial cells was amplified by pre-transfection of SOCS1 siRNA but was partly reduced with SOCS1 overexpression by adenoviral delivery. Therefore, TWEAK/Fn14 activation contributes to renal fibrosis in lupus nephritis involving the depression of SOCS1 function.
Subject(s)
Cytokine TWEAK/metabolism , Kidney/metabolism , Kidney/pathology , Signal Transduction , Suppressor of Cytokine Signaling 1 Protein/metabolism , TWEAK Receptor/metabolism , Animals , Down-Regulation , Female , Fibrosis , Inhibitor of Apoptosis Proteins/metabolism , Mesangial Cells/metabolism , Mice , NF-kappa B/metabolism , TNF Receptor-Associated Factor 2/metabolism , Up-RegulationABSTRACT
Recently, increasing evidence showed that circular RNAs (circRNAs) play critical roles in tumor progression. However, the roles of hsa_circ_0062389 in non-small cell lung cancer (NSCLC) development remain unclear. In the present study, hsa_circ_0062389 expression was significantly increased in NSCLC tissues and cell lines. High hsa_circ_0062389 expression was associated with advanced TNM stage and lymph-node metastasis. Function assays showed that hsa_circ_0062389 suppression reduced NSCLC cells proliferation and arrested cell cycle in G0/G1 phase. In mechanism, hsa_circ_0062389 directly interacted with miR-103a-3p in NSCLC, and CCNE1 acted as a target of miR-103a-3p. Furthermore, rescue assays showed that miR-103a-3p suppression or CCNE1 overexpression abolished the effects of hsa_circ_0062389 suppression on lung cancer cells progression. Therefore, our results showed that the hsa_circ_0062389/miR-103a-3p/CCNE1 axis might contribute to the tumorigenesis of NSCLC, which provided a new strategy for cancer treatment.
