A20 deficiency leads to angiogenesis of pulmonary artery endothelial cells through stronger NF-κB activation under hypoxia

TNFAIP3 mediates FGFR1 activation-induced breast cancer angiogenesis by promoting VEGFA expression and secretion

PURPOSE

To investigate the role and mechanism of TNF-inducible protein 3(TNFAIP3) in breast cancer angiogenesis induced by fibroblast growth factor receptor1 (FGFR1) activation.

METHODS

The immunohistochemical assay was used to detect the expression of vascular endothelial cell marker CD31 and CD105 in mice DCIS.COM-iFGFR1 transplanted tumor (previously established by our group). The effects of TNFAIP3 knockout/knockdown breast cancer cell lines on angiogenesis, migration, and invasion of Human Umbilical Vein Endothelial Cells (HUVEC) were detected by the tubulogenesis and Trewells assay. RNA-seq analysis of TNFAIP3 downstreams differential genes after TNFAIP3 knockdown. The expression and secretion of VEGFA after FGFR1 activation in breast cancer cells were detected by qPCR, Western blot, and ELISA.

RESULTS

Immunohistochemistry showed that TNFAIP3 knockout inhibited the expression of CD31 and CD105 in DCIS grafted tumors promoted by FGFR1 activation. Tubulogenesis and Trewells experiments showed that TNFAIP3 gene knockout/knockdown inhibited the angiogenesis, migration, and invasion of HUVEC cells promoted by FGFR1 activation. qPCR assay showed that VEGFA mRNA level in the TNFAIP3 knockdown cell line was significantly down-regulated (p < 0.05). qPCR, Western blot and ELISA results showed that TNFAIP3 gene knockout/knockdown could inhibit the expression and secretion of VEGFA in breast cancer cells induced by FGFR1 activation.

CONCLUSION

TNFAIP3 promotes breast cancer angiogenesis induced by FGFR1 activation through the expression and secretion of VEGFA.

Protective role of zinc in the pathogenesis of respiratory diseases

Respiratory diseases remain a major cause of morbidity and mortality worldwide. An imbalance of zinc, an essential trace element, is associated with a variety of lung diseases. We reviewed and summarized recent research (human subjects, animal studies, in vitro studies) on zinc in respiratory diseases to explore the protective mechanism of zinc from the perspective of regulation of oxidative stress, inflammation, lipid metabolism, and apoptosis. In the lungs, zinc has anti-inflammatory, antioxidant, and antiviral effects; can inhibit cancer cell migration; can regulate lipid metabolism and immune cells; and exerts other protective effects. Our comprehensive evaluation highlights the clinical and experimental effects of zinc in the pathogenesis of respiratory diseases. Our analysis also provides insight into the clinical application of zinc-targeted therapy for respiratory diseases.

Restricted Activation of the NF-κB Pathway in Individuals with Latent Tuberculosis Infection after HIF-1α Blockade

Tuberculous granuloma formation is mediated by hypoxia-inducible factor 1 alpha (HIF-1α), and is essential for establishing latent tuberculosis infection (LTBI) and its progression to active tuberculosis (TB). Here, we investigated whether HIF-1α expression and adjacent mechanisms were associated with latent or active TB infection. Patients with active TB, individuals with LTBI, and healthy controls were recruited, and the expression of cytokine genes IL15, IL18, TNFA, IL6, HIF1A, and A20 in peripheral blood mononuclear cells (PBMCs) and serum vitamin D (25(OH)D3) levels were evaluated. Additionally, nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α) levels were analyzed in PBMC lysates and culture supernatants, respectively, after HIF-1α blockade with 2-methoxyestradiol. We observed that IL-15 expression was higher in individuals with LTBI than in patients with active TB, while IL-18 and TNF-α expression was similar between LTBI and TB groups. Additionally, serum 25(OH)D3 levels and expression of IL-6, HIF1A, and A20 were higher in patients with active TB than in individuals with LTBI. Moreover, PBMCs from individuals with LTBI showed decreased NF-κB phosphorylation and increased TNF-α production after HIF-1α blockade. Together, these results suggest that under hypoxic conditions, TNF-α production and NF-κB pathway downregulation are associated with the LTBI phenotype.

A20 Is Increased in Fetal Lung in a Sheep LPS Model of Chorioamnionitis

Chorioamnionitis is associated with an increased risk of preterm birth and aggravates adverse outcomes such as BPD. Development of BPD is associated with chronic inflammatory reactions and oxidative stress in the airways which may be antenatally initiated by chorioamnionitis. A20 is an immunomodulatory protein involved in the negative feedback regulation of inflammatory reactions and is a possible regulator protein in oxidative stress reactions. The influence of chorioamnionitis on A20 gene regulation in the fetal lung is unknown. We characterized the influence of LPS and proinflammatory cytokines on A20 expression in human lung endothelial (HPMEC-ST1.6R) and epithelial (A549) cells in vitro by real-time PCR and/or western blotting and used a sheep model of LPS-induced chorioamnionitis for in vivo studies. To study the functional role of A20, endogenous A20 was overexpressed in HPMEC-ST1.6R and A549 cells. LPS induced proinflammatory cytokines in HPMEC-ST1.6R and A549 cells. Both LPS and/or proinflammatory cytokines elevated A20 at transcriptional and translational levels. Intra-amniotic LPS transiently increased IL-1β, IL-6, IL-8, and TNF-α mRNA levels in fetal lamb lungs, associated with an increase in A20 mRNA and protein levels. Overexpression of A20 reduced proinflammatory cytokines in vitro. Repeated LPS exposure induced LPS tolerance for proinflammatory cytokines and A20 in vitro and in vivo. Antenatal inflammation induced a transient increase in proinflammatory cytokines in the preterm fetal lung. The expression of proinflammatory cytokines increased expression of A20. Elevated A20 may have a protective role by downregulating chorioamnionitis-triggered fetal lung inflammation. A20 may be a novel target for pharmacological interventions to prevent chorioamnionitis-induced airway inflammation and lung damage, which can result in BPD later in life.

The prognostic evaluation of CA19-9, D-dimer and TNFAIP3/A20 in patients with pancreatic ductal adenocarcinoma

ABSTRACT

This study aimed to explore the significance and prognostic value of serum tumor-associated carbohydrate antigen 19-9 (CA19-9), D-dimer, and tumor necrosis factor alpha-induced protein 3 (TNFAIP3/A20) in patients with pancreatic ductal adenocarcinoma (PDAC).Our study included 148 patients treated for PDAC at Northern Jiangsu People's Hospital Affiliated to Yangzhou University from January 2012 to December 2016. Cutoff prognostic values were predicted using the receiver operating characteristic (ROC) curve. The Kaplan-Meier method was used to assess the survival rates of patients. Univariate and multivariate COX regression analyses were used to evaluate the prognostic factors.The recommended cutoff values of neutrophil-lymphocyte rate (NLR), platelet-lymphocyte rate (PLR), CA19-9, and D-dimer were 2.04 (sensitivity, 0.59; specificity, 0.9; area under the ROC curve [AUC], 0.749; P < .001), 52.94 (sensitivity, 0.73; specificity, 0.95; AUC, 0.829; P < .001), 176.66 U/mL (sensitivity, 0.7; specificity, 0.9; AUC, 0.794; P < .001), and 1.18 mg/L (sensitivity, 0.82; specificity, 0.9; AUC, 0.845; P < .001), respectively. Positive TNFAIP3/A20 expression was considered as an inclusion criterion. Serum CA19-9 expression was related with lymph node metastasis (P = .010), tumor-lymph node-metastasis (TNM) stage (P < .001), and survival rate (P < .001). D-dimer was correlated with tumor differentiation grade (P = .014), tumor size (P = .045), TNM stage (P < .001), and survival rate (P < .001). TNFAIP3/A20 was correlated with tumor differentiation grade (P < .001), body mass index (BMI) (P < .001), TNM stage (P = .014), and survival rate (P < .001). Kaplan-Meier curves showed that PDAC patients had significant differences in CA19-9, D-dimer, and TNFAIP3/A20 expressions (P < .05). CA19-9, D-dimer, TNM stage, tumor differentiation grade, and TNFAIP3/A20 were independent prognostic markers for PDAC in univariate and multivariate COX analyses.CA19-9, D-dimer, and TNFAIP3/A20 were found to be independent prognostic markers for PDAC patients.

p38/JNK Is Required for the Proliferation and Phenotype Changes of Vascular Smooth Muscle Cells Induced by L3MBTL4 in Essential Hypertension

Aim

Hypertension is a complicated disorder with multifactorial etiology and high heritability. Our previous work has identified L3MBTL4 as a novel susceptibility gene for the development of essential hypertension, accompanied with activation of p38/JNK. Yet, little evidence has been reported whether p38/JNK contributed directly to L3MBTL4-induced vascular remodeling and exploring the potential mechanism of L3MBTL4 in vascular smooth muscle cells (VSMCs).

Methods

We evaluated the contribution of L3MBTL4 on proliferation, migration, and phenotype changes of VSMCs and further explored the critical role of p38 and JNK signaling pathway underlying.

Results

In L3MBTL4 transgenic rats, we found that the elevated blood pressure, increased left ventricular hypertrophy, and thickened vascular media layer were significantly relieved by both p38 and JNK inhibitors. Meanwhile, increased cell proliferation, advanced cell cycle progression, greater migratory capability, and synthetic phenotype were observed in L3MBTL4 overexpressed VSMCs, which could be blocked by either p38 or JNK inhibitor.

Conclusions

Our findings pinpointed that p38 and JNK were required for the proliferation and phenotype changes of VSMCs induced by L3MBTL4 in hypertension. These novel findings yield new insights into the genetic and biological basis of hypertension and are fundamental for further studies to explore the intervention strategies targeting L3MBTL4 and p38/JNK to counteract the progression of hypertension.

A20 inhibits osteoclastogenesis via TRAF6-dependent autophagy in human periodontal ligament cells under hypoxia

OBJECTIVES

A20 exerts an anti-osteoclastogenic effect through the inhibition of NF-κB signalling in periodontitis. It also regulates autophagy via ubiquitin modification. This study was aimed at exploring the relationship between A20 and autophagy in anti-osteoclastogenesis in human periodontal ligament cells (hPDLCs) under hypoxia.

MATERIALS AND METHODS

Real-time PCR and Western blot were used to detect relative mRNA and protein levels. The formation of autophagosomes was measured by TEM. Osteoclastic differentiation was assessed by TRAP staining and hydroxyapatite resorption assay. The interactions between different proteins were observed by co-IP.

RESULTS

Cells cultured under 2% O₂ exhibited decreased A20 expression and increased RANKL/OPG (R/O) ratio. There was a negative correlation between A20 and TRAF6, and similar results were found with autophagic flux. A20 delayed the increase in R/O ratio under hypoxia. Autophagy in hPDLCs and osteoclast differentiation and hydroxyapatite resorption areas in mouse bone marrow mononuclear cells (BMMCs) were inhibited by A20. Moreover, inhibition of autophagy using 3-MA resulted in increased expression of A20 and decreased number and function of osteoclasts. In addition, A20 inhibited polyubiquitination at K63 and enhanced that at K48 in TRAF6 to suppress autophagy under hypoxic conditions.

CONCLUSIONS

A20 inhibits osteoclastogenesis via inhibition of TRAF6-dependent autophagy in hPDLCs under hypoxia. These findings suggest that A20 may be a key gene target during bone loss in periodontitis via TRAF6-mediated inhibition of autophagy.

Endothelial microvesicles in hypoxic hypoxia diseases

Hypoxic hypoxia, including abnormally low partial pressure of inhaled oxygen, external respiratory dysfunction-induced respiratory hypoxia and venous blood flow into the arterial blood, is characterized by decreased arterial oxygen partial pressure, resulting in tissue oxygen deficiency. The specific characteristics include reduced arterial oxygen partial pressure and oxygen content. Hypoxic hypoxia diseases (HHDs) have attracted increased attention due to their high morbidity and mortality and mounting evidence showing that hypoxia-induced oxidative stress, coagulation, inflammation and angiogenesis play extremely important roles in the physiological and pathological processes of HHDs-related vascular endothelial injury. Interestingly, endothelial microvesicles (EMVs), which can be induced by hypoxia, hypoxia-induced oxidative stress, coagulation and inflammation in HHDs, have emerged as key mediators of intercellular communication and cellular functions. EMVs shed from activated or apoptotic endothelial cells (ECs) reflect the degree of ECs damage, and elevated EMVs levels are present in several HHDs, including obstructive sleep apnoea syndrome and chronic obstructive pulmonary disease. Furthermore, EMVs have procoagulant, proinflammatory and angiogenic functions that affect the pathological processes of HHDs. This review summarizes the emerging roles of EMVs in the diagnosis, staging, treatment and clinical prognosis of HHDs.

Ginsenoside F1 Ameliorates Endothelial Cell Inflammatory Injury and Prevents Atherosclerosis in Mice through A20-Mediated Suppression of NF-kB Signaling

Atherosclerosis (AS) is a chronic inflammatory disease and endothelial cell injury is the initial event. In this study, we investigated the protective effects of ginsenoside F1 (GF1) on AS and the potential molecular mechanisms of ox-LDL induced endothelial injury. ApoE-/- mice were fed a high fat diet and orally treated with GF1 (50 mg/kg/day) for 8 weeks. Atherosclerotic plaque and LOX-1, TLR4, NF-κB expression levels in the aortic root and inflammatory factor MPO in whole body were measured. The treatment with GF1 induced a remarkable reduction in the atherosclerotic lesion area, LOX-1, TLR4 expression and decreased the MPO distribution. Meanwhile, in vitro study, we confirmed that GF1 treatment greatly increased ox-LDL-injured endothelial cell viability, ameliorated LOX-1, TLR4 expression levels and reduced monocytes adhesion. Protein microarray demonstrated that GF1 significantly inhibited G-CSF, ICAM-1, MIP-1δ, IL-1α, IL-15, IL-16 levels. Mechanistically, the GF1 treatment suppressed the NF-κB nuclear translocation. Furthermore, our data indicated that GF1 significantly increased A20 expression level and A20 siRNA markedly abolished the attenuation of GF1 on NF-κB nuclear translocation and inflammatory factors expression. Our results suggest that the GF1 may be a potential drug for anti-atherosclerosis.