NF-κB Activation Research Articles

Radiosensitizing effects of CDK4/6 inhibitors in hormone receptor-positive and HER2-negative breast cancer mediated downregulation of DNA repair mechanism and NF-κB-signaling pathway

CDK4/6 inhibitors combined with endocrine therapy prolonged survival in hormone receptor (HR)-positive and HER2-negative advanced breast cancer. We investigated whether CDK4/6 inhibitors enhance radiosensitivity and their underlying mechanisms of this subtype of breast cancer. In vitro and in vivo experiments were conducted using two HR-positive and HER2-negative breast cancer cell lines (MCF-7 and T-47D), CDK4/6 inhibitors (ribociclib and palbociclib) and radiotherapy (RT) to assess the biological functions and mechanisms. The radiation-enhancing effect was assessed using clonogenic assays; γH2AX and 53BP1 levels were assessed by immunofluorescence to evaluate DNA damage. The levels of phospho (p)-ERK, c-Myc, and DNA-double strand break (DSB)-related molecules, p-DNA-PKcs, Rad51, and p-ATM, were assessed by western blotting. We used an NF-κB p65 transcription factor assay kit to evaluate NF-κB activity. We evaluated the antitumor effect of the combination of RT and ribociclib through the MCF-7 orthotopic xenograft model. The synergistic effects of combining RT with ribociclib and palbociclib pretreatment were demonstrated by clonogenic assay. CDK4/6 inhibitors synergistically increased the numbers of RT-induced γH2AX and 53BP1, downregulated the expression of p-DNA-PKcs, Rad51 and p-ATM activated by RT, and reduced RT-triggering p-ERK expression, NF-κB activation, and its down-streaming gene, c-Myc. Combined ribociclib and RT reduced the growth of MCF-7 cell xenograft tumors, and downregulated the immunohistochemical expression of p-ERK, p-NF-κB p65, and c-Myc compared to that in the control group. Combining CDK4/6 inhibitors enhanced radiosensitivity of HR-positive and HER2-negative breast cancer cells at least by reducing DNA-DSB repair and weakening the activation of ERK and NF-κB signaling by RT.

Heat-Processed Soybean Germ Extract and Lactobacillus gasseri NK109 Supplementation Reduce LPS-Induced Cognitive Impairment and Colitis in Mice.

Soybean alleviates cognitive impairment. In our preparatory experiment, we found that dry-heat (90 °C for 30 min)-processed soybean embryo ethanol extract (hSE) most potently suppressed lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α expression in BV2 cells among dry-heat-, steaming-, and oil exclusion-processed soybean embryo ethanol extracts (SEs). Heat processing increased the absorbable soyasaponin Bb content of SE. Therefore, we investigated whether hSE and its supplement could mitigate LPS-impaired cognitive function in mice. Among dry-heat-, steaming-, and oil exclusion-processed SEs, hSE mitigated LPS-impaired cognitive function more than parental SE. hSE potently upregulated LPS-suppressed brain-derived neurotropic factor (BDNF) expression in the hippocampus, while LPS-induced TNF-α and IL-1β expression in the hippocampus and colon were downregulated. Lactobacillus gasseri NK109 additively increased the cognitive function-enhancing activity of hSE in mice with LPS-induced cognitive impairment as follows: the hSE and NK109 mix potently increased cognitive function and hippocampal BDNF expression and BDNF-positive neuron cell numbers and decreased TNF-α expression and NF-κB-positive cell numbers in the hippocampus and colon. These findings suggest that hSE and its supplement may decrease colitis and neuroinflammation by suppressing NF-κB activation and inducing BDNF expression, resulting in the attenuation of cognitive impairment.

1,3-Disubstituted thiourea derivatives: Promising candidates for medicinal applications with enhanced cytotoxic effects on cancer cells

The distinct chemical structure of thiourea derivatives provides them with an advantage in selectively targeting cancer cells. In our previous study, we selected the most potent compounds, 2 and 8, with 3,4-dichloro- and 3-trifluoromethylphenyl substituents, respectively, across colorectal (SW480 and SW620), prostate (PC3), and leukemia (K-562) cancer cell lines, as well as non-tumor HaCaT cells. Our research has demonstrated their anticancer potential by targeting key molecular pathways involved in cancer progression, including caspase 3/7 activation, NF-κB (Nuclear Factor Kappa-light-chain-enhancer of activated B cells) activation decrease, VEGF (Vascular Endothelial Growth Factor) secretion, ROS (Reactive Oxygen Species) production, and metabolite profile alterations. Notably, these processes exhibited no significant alterations in HaCaT cells. The effectiveness of the studied compounds was also tested on spheroids (3D culture). Both derivatives 2 and 8 increased caspase activity, decreased ROS production and NF-κB activation, and suppressed the release of VEGF in cancer cells. Metabolomic analysis revealed intriguing shifts in cancer cell metabolic profiles, particularly in lipids and pyrimidines metabolism. Assessment of cell viability in 3D spheroids showed that SW620 cells exhibited better sensitivity to compound 2 than 8. In summary, structural modifications of the thiourea terminal components, particularly dihalogenophenyl derivative 2 and para-substituted analog 8, demonstrate their potential as anticancer agents while preserving safety for normal cells.

Origin recognition complex subunit 6 (ORC6) is a key mediator of LPS-induced NFκB activation and the pro-inflammatory response

Lipopolysaccharide (LPS)-activated pro-inflammatory responses play a critical role in sepsis, a life-threatening condition. This study investigates the role of origin recognition complex subunit 6 (ORC6) in LPS responses in macrophages and monocytes. Silencing ORC6 using targeted shRNA significantly reduced LPS-induced expression and production of IL-1β (interleukin-1 beta), TNF-α (tumor necrosis factor alpha), and IL-6 (interleukin-6) in THP-1 human macrophages, peripheral blood mononuclear cells (PBMCs), and bone marrow-derived macrophages (BMDMs). Additionally, ORC6 knockout (KO) via the CRISPR/Cas9 method in THP-1 macrophages inhibited LPS-induced pro-inflammatory responses, while ectopic overexpression of ORC6 enhanced LPS-induced expression and production of pro-inflammatory cytokines. ORC6 is crucial for the activation of the nuclear factor kappa B (NFκB) signaling cascade in macrophages and monocytes. LPS-induced NFκB activation was largely inhibited by ORC6 silencing or KO, but potentiated following ORC6 overexpression. Mechanistically, ORC6 associated with nuclear p65 after LPS stimulation, an interaction necessary for NFκB activation. Overexpression of ORC6 did not recover the reduced pro-inflammatory response to LPS in THP-1 macrophages with silenced p65. Furthermore, the NFκB inhibitor BMS-345,541 nearly eliminated the pro-inflammatory response enhanced by ORC6 overexpression in response to LPS. Further studies revealed that ORC6 depletion inhibited NFκB activation induced by double-stranded RNA (dsRNA) and high mobility group box 1 (HMGB1) in THP-1 macrophages. In vivo experiments demonstrated that macrophage-specific knockdown of ORC6 protected mice from LPS-induced septic shock and inhibited LPS-stimulated production of IL-1β, TNF-α, and IL-6 in mouse serum. ORC6 silencing also inhibited LPS-induced NFκB activation in ex vivo cultured PBMCs following macrophage-specific knockdown of ORC6. These findings highlight ORC6 as a pivotal mediator in LPS-induced NFκB activation and the pro-inflammatory response in sepsis, suggesting that targeting ORC6 could be a novel therapeutic strategy for managing sepsis and related inflammatory conditions.

PRELP inhibits the progression of oral squamous cell carcinoma via inactivation of the NF-κB pathway

ObjectivesThe aim of this study was to investigate the role and molecular mechanism of proline/arginine-rich end leucine-rich repeat protein (PRELP), a secreted protein in extracellular matrix, in oral squamous cell carcinoma (OSCC) progression. DesignPRELP expression in OSCC was analyzed in the Gene Set Enrichment (GSE) 138206, GSE37991, and GSE23558 datasets as well as cell lines. Also, PRELP expression and its relationship with prognosis and immune infiltration in head and neck squamous cell carcinoma (HNSCC) were confirmed by bioinformatics analysis. The proliferation, apoptosis, invasion, epithelial-to-mesenchymal transition (EMT) and NF-κB activation were detected after alteration of PRELP expression in OSCC cells using CCK-8, EdU, flow cytometry, Transwell, real-time PCR, immunofluorescence and Western blot. Additionally, an NF-κB inhibitor PDTC was used to confirm the regulation mechanism of PRELP. ResultsThe expression of PRELP in OSCC tissues, cells and in HNSCC samples was low. HNSCC patients with higher PRELP expression was associated with longer overall survival. A positive correlation between PRELP expression and immune cell infiltration was found in HNSCC. Upregulation of PRELP inhibited, whereas PRELP silencing promoted, the proliferation, invasion and EMT of OSCC cells. Also, overexpression of PRELP promoted cell apoptosis. Mechanistically, PRELP suppressed p65 phosphorylation and nuclear translocation. And PDTC treatment partially reversed the influences of PRELP knockdown on the malignant behaviors in OSCC cells. ConclusionPRELP suppressed OSCC progression via inactivation of the NF-κB pathway. Targeting PRELP may be a potential approach for OSCC treatment.

Unveiling the Hidden Links: Periodontal Disease, Fusobacterium Nucleatum, and Cancers.

Fusobacterium nucleatum (F. nucleatum), an anaerobic, gram-negative microbe, commonly found in human dental biofilm and the gut flora. It has long been known to have a higher concentration in periodontal disease and has recently been implicated in bothoral and distant cancers such as colorectal,gastrointestinal, esophageal, breast, pancreatic hepatocellular,and genitourinary cancers.However, the mechanism of its involvement in the development of cancer has not been fully discussed. This review aims to cover biological molecular and clinical aspects of F. nucleatumand cancers. Studies indicate F. nucleatum promotes tumor development through chronic inflammation, immune evasion, cell proliferation activation, and direct cell interactions, as in oral squamous cell carcinoma (OSCC). In colorectal cancer (CRC), F. nucleatum contributes to tumorigenesis through β-catenin signaling and NF-κB activation. It also induces autophagy, leading to chemoresistance in CRC and esophageal cancers, and enhances tumor growth and metastasis in breast cancer by reducing T-cell infiltration. F. nucleatum is linked to carcinogenesis and increased bacterial diversity in OSCC, with improved oral hygiene potentially preventing OSCC. F. nucleatum triggers cancer by causing mutations and epigenetic changes through cytokines and reactive oxygen species. It also promotes chemoresistance in CRC. F. nucleatum may potentially serve as a diagnostic tool in various cancers, with non-invasive detection methods available. Further investigation is needed to discover its potential in the diagnosis and treatment of OSCC and other cancers.

Green Synthesis and Chemical Characterization of Silver Nanoparticles by Tribulus terrestris for the Treatment of Myocardial Infarction.

Silver nanoparticles (AgNPs) are commonly utilized in the medical sector, particularly in cardiovascular applications. Nevertheless, there is a studies scarcity examining the impact of AgNPs on myocardial infarction protection. A green formulation of AgNPs was documented in the research. Different spectroscopic methods were utilized to examine the AgNPs, and their potential for treating myocardial infarction was explored. The NPs exhibited a spherical morphology upon formation. Isoproterenol (85mg/kg) was administered to induce myocardial infarction in mice. The mice were categorized into four distinct groups (n = 15): (1) untreated; (2) normal; (3,4) AgNPs + isoproterenol at various doses (5 and 50µg/kg). The activation of PPAR-Υ/NF-κB and subsequent cytokine release induced by lipopolysaccharide were quantified using real-time PCR and western blot techniques. Subsequent to the administration of AgNPs at different doses, the evaluation of cardiac function was conducted through biochemical, histochemical, and electrocardiogram (ECG) analysis. AgNPs significantly inhibit the levels of myocardial injury markers, reduce the incidence of mortality, and improve the condition of ventricular wall infarction. In addition, the administration of AgNPs effectively prevents the characteristic ST segment depression when compared to animals with myocardial infarction. The positive effects of AgNPs could potentially be attributed to the restoration of normal gene expression in PPAR-Υ/NF-κB/ΙκB-α/ΙΚΚα/β and PPAR-Υ phosphorylation pathways. Additionally, the application of AgNPs led to a reduction in the levels of pro-inflammatory cytokines in the hearts of mice suffering from myocardial infarction. The expression suppression of inflammation cytokines and cell death was significantly reduced by AgNPs. Recent findings suggest that AgNPs possess cardioprotective properties on isoproterenol-induced myocardial infarction, possibly by the inhibition of NF-κB signaling and activation of PPAR-γ. To summarize, the present study introduces a contemporary therapeutic approach for treating myocardial infarction in clinical settings.

Evolutionary and functional analyses reveal a role for the RHIM in tuning RIPK3 activity across vertebrates.

Receptor interacting protein kinases (RIPK) RIPK1 and RIPK3 play important roles in diverse innate immune pathways. Despite this, some RIPK1/3-associated proteins are absent in specific vertebrate lineages, suggesting that some RIPK1/3 functions are conserved while others are more evolutionarily labile. Here, we perform comparative evolutionary analyses of RIPK1-5 and associated proteins in vertebrates to identify lineage-specific rapid evolution of RIPK3 and RIPK1 and recurrent loss of RIPK3-associated proteins. Despite this, diverse vertebrate RIPK3 proteins are able to activate NF-κB and cell death in human cells. Additional analyses revealed a striking conservation of the RIP homotypic interaction motif (RHIM) in RIPK3, as well as other human RHIM-containing proteins. Interestingly, diversity in the RIPK3 RHIM can tune activation of NF-κB while retaining the ability to activate cell death. Altogether, these data suggest that NF-κB activation is a core, conserved function of RIPK3, and the RHIM can tailor RIPK3 function to specific needs within and between species.

The new pattern for dual NOTCH pathway involving nuclear transcription and mitochondrial regulation supports therapeutic mechanism of 4-butyl benzophenone derivatives against SIRS

The systemic inflammatory response syndrome (SIRS) represents a self-amplifying cascade of inflammatory reactions and pathophysiological states triggered by infectious or non-infectious factors. The identification of disease targets and differential proteins in the liver (the unique and important immune organ) of SIRS mice treated with the lead compound D1 was conducted using the Genecards database and proteomic analysis, respectively. Subsequently, NOTCH1 was identified as the potential hub target via an intersection analysis between the aforementioned differentially expressed proteins and disease targets. Based on our previous research on the structure-activity relationship, we designed and synthesized a series of SIRS-related derivatives, wherein butyl, halogen, and ester groups were incorporated into benzophenone, aiming at exploring the anti-inflammatory protective action from the perspective of macrophage polarization. Notably, these derivatives exhibited a direct binding capability to the O-glucosylation site (SER496) or its vicinities (such as SER492, VAL485) of NOTCH1 using docking, SPR, DARTS, and CETSA techniques. Mechanistically, derivative D6 exerted anti-inflammatory effects via the dual NOTCH pathway. Firstly, it could inhibit NOTCH1 nuclear transcriptional activity, attenuate the interaction between NICD and RBPJK, concurrently suppress NF-κB and NLRP3 inflammasome (NLRP3, ASC, and cleaved CASP1) activation, and promote NICD (NOTCH1 active fragments) ubiquitination metabolism (the nuclear transcriptional pathway). Secondly, it might possess the ability to increase PGC1α level, subsequently, enhance ATP and MMP levels, mitigate ROS production, increase mitochondrial numbers, and ameliorate mitochondrial inflammatory damage (the mitochondrial pathway). Importantly, the activator Jagged1 could effectively reverse the aforementioned effects, while the inhibitor DAPT exhibited a synergistic effect, suggesting that the nuclear transcriptional regulation and mitochondrial regulation were both in a NOTCH1-dependent manner. Subsequently, it effectively alleviated the inflammatory response and preserved organ function as evidenced by up-regulating M2-type macrophage-related anti-inflammatory cytokines (IL10, TGFβ, CD206, and ARG1) and down-regulating M1-type macrophage-related pro-inflammatory cytokines (NO, IL6, IL18, iNOS, TNFα, CD86, and IL1β). In a word, derivative D6 modulated macrophage polarization and effectively mitigated SIRS by targeting inhibition of the dual NOTCH pathway.

MicroRNA miR-27a-5p reduces intestinal inflammation induced by Clostridioides difficile flagella by regulating the NF-κB signaling pathway.

Clostridioides difficile is a major cause of nosocomial post-antibiotic infections, often resulting in severe inflammation and watery diarrhea. Previous studies have highlighted the role of C. difficile flagellin FliC in activating the TLR5 receptor and triggering NF-κB cell signaling, leading to the release of pro-inflammatory cytokines. However, the microRNAs (miRNAs) mediated regulatory mechanisms underlying the FliC-induced inflammatory response remain unclear. miRNA expression levels were analyzed in Caco-2 intestinal epithelial cells following FliC stimulation, infection with the epidemic C. difficile R20291 strain, or its unflagellated mutant by RT-qPCR. Chemical inhibitors were used to block NF-κB signaling, and their impact on miR-27a-5p expression was assessed. Knockdown and overexpression experiments with miRNA inhibitor and mimic were conducted to elucidate miR-27a-5p's functional role in FliC-induced inflammatory responses. Additionally, a mouse model of C. difficile infection was treated with miR-27a-5p to evaluate its therapeutic potential in vivo. miR-27a-5p showed significant FliC-dependent overexpression in Caco-2 cells. Inhibition of NF-κB signaling suppressed miR-27a-5p overexpression. Knockdown of miR-27a-5p increased NF-κB activation and TNF-α and IL-8 cytokine production, while its overexpression had the opposite effect. Moreover, miR-27a-5p was overexpressed in the caeca of C. difficile-infected mice, correlating with intestinal IL-8 levels. Treatment of infected mice with miR-27a-5p mimic reduced disease severity and intestinal inflammation. miR-27a-5p plays a crucial role in regulating C. difficile-induced inflammation, suggesting its potential as a therapeutic target for controlling severe infection. These findings offer valuable insights into potential therapeutic strategies for managing C. difficile infection and associated inflammatory complications.

Cyld restrains the hyperactivation of synovial fibroblasts in inflammatory arthritis by regulating the TAK1/IKK2 signaling axis

TNF is a potent cytokine known for its involvement in physiology and pathology. In Rheumatoid Arthritis (RA), persistent TNF signals cause aberrant activation of synovial fibroblasts (SFs), the resident cells crucially involved in the inflammatory and destructive responses of the affected synovial membrane. However, the molecular switches that control the pathogenic activation of SFs remain poorly defined. Cyld is a major component of deubiquitination (DUB) machinery regulating the signaling responses towards survival/inflammation and programmed necrosis that induced by cytokines, growth factors and microbial products. Herein, we follow functional genetic approaches to understand how Cyld affects arthritogenic TNF signaling in SFs. We demonstrate that in spontaneous and induced RA models, SF-Cyld DUB deficiency deteriorates arthritic phenotypes due to increased levels of chemokines, adhesion receptors and bone-degrading enzymes generated by mutant SFs. Mechanistically, Cyld serves to restrict the TNF-induced hyperactivation of SFs by limiting Tak1-mediated signaling, and, therefore, leading to supervised NF-κB and JNK activity. However, Cyld is not critically involved in the regulation of TNF-induced death of SFs. Our results identify SF-Cyld as a regulator of TNF-mediated arthritis and inform the signaling landscape underpinning the SF responses.

The protective mechanism of sevoflurane in pulmonary arterial hypertension via downregulation of TRAF6

Pulmonary arterial hypertension (PAH) is an obstructive vasculopathy that, if not promptly treated, culminates in right heart failure. Therefore, pre-clinical studies are needed to support and optimize therapeutic approaches of PAH. Here, we explore a prospective function of sevoflurane in experimental PAH through regulating TRAF6. Monocrotaline (MCT)-induced PAH rats were subjected to sevoflurane inhalation and intratracheal instillation of lentivirus overexpressing TRAF6. Platelet-derived growth factor (PDGF)-treated pulmonary artery smooth muscle cells (PASMCs) were exposed to sevoflurane and genetically manipulated for TRAF6 overexpression. It was found that MCT and PDGF challenge upregulated the levels of TRAF6 in rat lung tissues and PASMCs, but sevoflurane treatment led to reduced TRAF6 expression. Sevoflurane inhalation in MCT-induced rats resulted in alleviative pulmonary vascular remodeling, mitigated right ventricular dysfunction and hypertrophy, improved mitochondrial function and dynamics, and inactivation of NF-κB pathway. In vitro studies confirmed that exposure to sevoflurane repressed PDGF-induced proliferation, migration, and phenotype switching of PASMCs, and suppressed mitochondrial dysfunction and NF-κB activation in PDGF-stimulated PASMCs. The beneficial impact of sevoflurane on pathological changes of lung and cell phenotype of PASMCs were reversed by overexpression of TRAF6. In summary, our study suggested the protective properties of sevoflurane in targeting PAH by downregulating TRAF6 expression, providing a novel avenue for the management of PAH.

Molecular Cloning, Tissue Distribution and Antiviral Immune Response of Duck Src.

As a founding member of the Src family of kinases, Src has been confirmed to participate in the regulation of immune responses, integrin signaling, and motility. Ducks are usually asymptomatic carriers of RNA viruses such as Newcastle disease virus and avian influenza virus, which can be deadly to chickens. The beneficial role of Src in modulating the immune response remains largely unknown in ducks. Here, we characterized the duck Src and found that it contains a 192-base-pair 5' untranslated region, a 1602-base-pair coding region, and a 2541-base-pair 3' untranslated region, encoding 533 amino acid residues. Additionally, duSrc transcripts were significantly activated in duck tissues infected by Newcastle disease virus compared to controls. The duSrc transcripts were notably widespread in all tissues examined, and the expression level was higher in liver, blood, lung, pancreas, and thymus. Moreover, we found the expression levels of IFN-β, NF-κB, IRF3, and Src were significantly increased in DEFs after infection with 5'ppp dsRNA, but there was no significant difference before and after treatment in DF1 cells. Furthermore, overexpression of duSrc followed by stimulation with 5'ppp dsRNA led to an elevation of IFN-β levels. The SH3 and PTKc domains of duSrc contributed to promoting the activity of IFN-β and NF-κB in DEFs stimulated by 5'ppp dsRNA.

Scutellaria barbata D.Don and Scleromitrion diffusum (Willd.) R.J.Wang inhibits the progression of triple negative breast cancer though the activation inhibition of NF-κB triggered by CAFs-derived IL6

Ethnopharmacological relevanceThe treatment options for triple-negative breast cancer (TNBC) are limited. Traditional Chinese Medicine (TCM) plays an important role in the treatment of TNBC. The herb pair Scutellaria barbata D.Don and Scleromitrion diffusum (Willd.) R.J.Wang (SH) is commonly used in clinical practice for its anti-tumor properties. It has been proven to have good therapeutic effects on tumor-related diseases, but the underlying molecular mechanisms are not yet fully explained. Aim of studyThrough bioinformatics, it was validated that IL6, primarily derived from cancer-associated fibroblasts (CAFs), is associated with poor prognosis. Additionally, cell and animal experiments confirmed that SH inhibits tumor proliferation, migration, and growth in an orthotopic tumor model by suppressing the IL6/NF-κB pathway. Materials and methodsGEO, TCGA and HPA databases were used to analyze the prognostic value of CAFs and IL6, then IL6 resource was detected. After the bioinformatics, the influence of CAFs and CAFs-derived IL6 on TNBC was verified by experiments both in vitro and in vivo. Cell clone formation assay, wound-Healing assay, and Transwell assay were used to detect the promotion of CAFs and CAFs-derived IL6 and the inhibition of SH in vitro. TNBC model in mice was used to prove the promotion of CAFs and CAFs-derived IL6 and the inhibition of SH in vivo. The biological pathway of NF-κB was explored by western blotting through detecting unique molecules. ResultsBioinformatics analysis revealed that higher proportion of CAFs and elevated level of IL6 were significantly associated with poor prognosis in TNBC. At the same time, IL6 was proved predominantly derived from CAFs. After the indication of bioinformatics, experiments in vitro demonstrated that both CAFs and IL6 could enhance the clone formation and migration ability of MDA-MD-231 cells (231), furthermore, the promotion of CAFs was related with the level of IL6. Based on these data, mechanism was detected that CAFs-derived IL6 enhancement was closely related to the activation of NF-κB signaling pathway, while the activation can be reduced by SH. In the end, the promotion of CAFs/CAFs-derived IL6/NF-κB and the efficacy of SH inhibition were both confirmed by experiments in vivo. ConclusionsBioinformatics data indicates that higher proportion of CAFs and higher level of CAFs-derived IL6 are significantly related to poorer survival of TNBC. CAFs and CAFs-derived IL6 were proved to promote the progression of TNBC both in vitro and in vivo, and the process of which was significantly related to the activation of NF-κB. SH inhibited the progress of TNBC, which was proved to be closely related to CAFs/CAFs-derived IL6/NF-κB.

Divergent Processing of Cell Stress Signals as the Basis of Cancer Progression: Licensing NFκB on Chromatin.

Inflammation is activated by diverse triggers that induce the expression of cytokines and adhesion molecules, which permit a succession of molecules and cells to deliver stimuli and functions that help the immune system clear the primary cause of tissue damage, whether this is an infection, a tumor, or a trauma. During inflammation, short-term changes in the expression and secretion of strong mediators of inflammation occur, while long-term changes occur to specific groups of cells. Long-term changes include cellular transdifferentiation for some types of cells that need to regenerate damaged tissue, as well as death for specific immune cells that can be detrimental to tissue integrity if they remain active beyond the boundaries of essential function. The transcriptional regulator NFκB enables some of the fundamental gene expression changes during inflammation, as well as during tissue development. During recurrence of malignant disease, cell stress-induced alterations enable the growth of cancer cell clones that are substantially resistant to therapeutic intervention and to the immune system. A number of those alterations occur due to significant defects in feedback signal cascades that control the activity of NFκB. Specifically, cell stress contributes to feedback defects as it overrides modules that otherwise control inflammation to protect host tissue. NFκB is involved in both the suppression and promotion of cancer, and the key distinctive feature that determines its net effect remains unclear. This paper aims to provide a clear answer to at least one aspect of this question, namely the mechanism that enables a divergent response of cancer cells to critical inflammatory stimuli and to cell stress in general.

Extracellular RNA Induces Neutrophil Recruitment Via Toll-Like Receptor 3 During Venous Thrombosis After Vascular Injury.

Venous thromboembolism is associated with endothelial cell activation that contributes to the inflammation-dependent activation of the coagulation system. Cellular damage is associated with the release of different species of extracellular RNA (eRNA) involved in inflammation and coagulation. TLR3 (toll-like receptor 3), which recognizes (viral) single-stranded or double-stranded RNAs and self-RNA fragments, might be the receptor of these species of eRNA during venous thromboembolism. Here, we investigate how the TLR3/eRNA axis contributes to venous thromboembolism. Thrombus formation and size in wild-type and TLR3 deficient (-/-) mice were monitored by ultrasonography after venous thrombosis induction using the ferric chloride and stasis models. Mice were treated with RNase I, with polyinosinic-polycytidylic acid, a TLR3 agonist, or with RNA extracted from murine endothelial cells. Gene expression and signaling pathway activation were analyzed in HEK293T cells overexpressing TLR3 in response to eRNA or in human umbilical vein endothelial cells transfected with a small interference RNA against TLR3. Plasma clot formation on treated human umbilical vein endothelial cells was analyzed. Thrombosis exacerbated eRNA release invivo and increased eRNA content within the thrombus. RNase I treatment reduced thrombus size compared with vehicle-treated mice (P<0.05). Polyinosinic-polycytidylic acid and eRNA treatments increased thrombus size in wild-type mice (P<0.01 and P<0.05), but not in TLR3-/- mice, by reinforcing neutrophil recruitment (P<0.05). Mechanistically, TLR3 activation in endothelial cells promotes CXCL5 (C-X-C motif chemokine 5) secretion (P<0.001) and NFκB (nuclear factor kappa-light-chain-enhancer of activated B cells) activation (P<0.05). Finally, eRNA triggered plasma clot formation invitro (P<0.01). We show that eRNA and TLR3 activation enhance venous thromboembolism through neutrophil recruitment possibly through secretion of CXCL5, a potent neutrophil chemoattractant.

Catabolic mediators from TLR2-mediated proteoglycan aggrecan peptide-stimulated chondrocytes are reduced by Lactobacillus-conditioned media

In osteoarthritis (OA), extracellular matrix (ECM) digestion by cartilage-degrading enzymes drives cartilage destruction and generates ECM fragments, such as proteoglycan aggrecan (PG) peptides. PG peptides have been shown to induce immunological functions of chondrocytes. However, the role of PG peptides in stimulating catabolic mediators from chondrocytes has not been investigated. Therefore, we aim to determine the effects and its mechanism by which PG peptides induce chondrocytes to produce catabolic mediators in OA. Human chondrocytes were stimulated with IFNγ and various PG peptides either (i) with or (ii) without TLR2 blockade or (iii) with Lactobacillus species-conditioned medium (LCM), a genus of bacteria with anti-inflammatory properties. Transcriptomic analysis, cartilage-degrading enzyme production and TLR2-intracellular signaling activation were investigated. Chondrocytes treated with PG peptides p16-31 and p263-280 increased expression levels of genes associated with chondrocyte hypertrophy, cartilage degradation and proteolytic enzyme production. TLR2 downstream signaling proteins (STAT3, IkBα and MAPK9) were significantly phosphorylated in p263-280 peptide-stimulated chondrocytes. MMP-1 and ADAMTS-4 were significantly reduced in p263-280 peptides-treated condition with TLR2 blockade or LCM treatment. Phosphorylation levels of IkBa, ERK1/2 and MAPK9 were significantly decreased with TLR2 blockade, but only phosphorylation levels of MAPK9 was significantly decreased with LCM treatment. Our study showed that PG peptide stimulation via TLR2 induced cartilage-degrading enzyme production via activation of MAPK, NFκB and STAT3 pathways.

Trifolirhizin reduces osteoclast formation and prevents inflammatory osteolysis by inhibiting RANKL-induced activation of NF-κB and MAPK signaling pathways and ROS.

Inflammatory osteolysis is often caused by the excessive activation of osteoclasts stimulated by bacterial products such as lipopolysaccharide. The natural flavonoid trifolirhizin (TRI) has anti-inflammatory properties; however, its function in inflammatory bone lysis remains unclear. This study aimed to elucidate the potential regulatory mechanisms of TRI in osteoclasts.Tartrate-resistant acid phosphatase (TRAP) staining, acid secretion assays, podosomal actin belt fluorescence staining, and bone resorption assays were used to investigate the effects of TRI on osteoclast differentiation and bone resorption. A reactive oxygen species (ROS) measurement kit was used to detect the effect of TRI on ROS levels in osteoclasts. The effects of TRI on genes and signaling pathways related to osteoclast differentiation were determined by quantitative polymerase chain reaction (qPCR) and western blotting. A mouse model of lipopolysaccharide-mediated inflammatory osteolysis was established, and the effects of TRI treatment on bone mass were observed using micro-CT and histological examination. Mechanistically, TRI reduced ROS production by inhibiting receptor activator of nuclear factor-κB ligand (RANKL)-induced activation of the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, and by upregulating the expression levels of the anti-ROS enzymes heme oxygenase-1 (HO-1) and catalase (CAT), which contributed to the degradation of ROS, ultimately leading to a decrease in osteoclastogenesis. TRI inhibited osteoclast formation and ameliorated lipopolysaccharide (LPS)-mediated inflammatory osteolysis. Thus, TRI may be a candidate agent for anti-inflammatory osteolysis.

Aromadendrin Inhibits Lipopolysaccharide-Induced Inflammation in BEAS-2B Cells and Lungs of Mice.

Aromadendrin is a phenolic compound with various biological effects such as anti-inflammatory properties. However, its protective effects against acute lung injury (ALI) remain unclear. Therefore, this study aimed to explore the ameliorative effects of aromadendrin in an experimental model of lipopolysaccharide (LPS)-induced ALI. In vitro analysis revealed a notable increase in the levels of cytokine/chemokine formation, nuclear factor kappa B (NF-κB) activation, and myeloid differentiation primary response 88 (MyD88)/toll-like receptor (TLR4) expression in LPS-stimulated BEAS-2B lung epithelial cell lines that was ameliorated by aromadendrin pretreatment. In LPS-induced ALI mice, the remarkable upregulation of immune cells (ICs) and IL-1β/IL-6/TNF-α levels in the bronchoalveolar lavage fluid (BALF) and inducible nitric oxide synthase (iNOS)/cyclooxygenase-2 (COX-2)/CD68 expression in lung was decreased by the oral administration of aromadendrin. Histological analysis revealed the presence of cells in the lungs of acute lung injury (ALI) mice, which was alleviated by aromadendrin. In addition, aromadendrin ameliorated lung edema. This in vivo effect of aromadendrin was accompanied by its inhibitory effect on LPS-induced NF-κB activation, MyD88/TLR4 expression, and signal transducer and activator of transcription 3 (STAT3) activation. Furthermore, aromadendrin increased the expression of heme oxygenase-1 (HO-1)/ NAD(P)H quinone dehydrogenase 1 (NQO1) in the lungs of ALI mice. In summary, the in vitro and in vivo studies demonstrated that aromadendrin ameliorated endotoxin-induced pulmonary inflammation by suppressing cytokine formation and NF-κB activation, suggesting that aromadendrin could be a useful adjuvant in the treatment of ALI.

Abstract Or110: Inflammation-induced endothelial cell activation and angiogenic sprouting are downmodulated by ubiquitin-specific peptidase 20

The deubiquitinase ubiquitin-specific peptidase 20 (USP20) reverses lysine-63 ubiquitination of the signaling adaptor TRAF6 and suppresses nuclear-factor-κB (NFκB) activation induced by proatherogenic stimuli in vascular smooth muscle cells (SMCs). Dephosphorylation of USP20 at Ser 334 augments USP20/TRAF6 binding and USP20-mediated TRAF6 deubiquitination, consequently decreasing NFκB signaling. SMC USP20 activity also attenuates atherosclerosis in Ldlr -/- mice. NFκB is a key mediator of vascular endothelial cell (EC) activation and inflammation-driven angiogenesis, which promotes growth and rupture of atherosclerotic plaques. We tested the hypothesis that USP20 attenuates EC NFκB signaling and decreases angiogenesis, with both in vitro and ex vivo models to study the role of USP20 in EC activation and ensuing angiogenesis. We analyzed experimental data by one-way ANOVA followed by Holm-Šídák's multiple comparisons test. Cytokine-induced NFκB activity was elevated in primary ECs isolated from Usp20 -/- mice as compared with ECs from congenic wild type (WT) mice (N=3, p&lt;0.001). Assessed by scratch-wound healing and spheroid assays, respectively, migration and angiogenesis of mouse coronary endothelial cells (MCECs) transduced with recombinant adenoviruses was (a) increased by inactive USP20 or phospho-mimetic USP20(S334D) (migration, N=4, P&lt;0.05; angiogenesis, N=6, P&lt;0.01), and (b) decreased by transduction with WT USP20 or phospho-resistant USP20(S334A) (migration, N=4, P&lt; 0.05; angiogenesis, N=6, P&lt;0.01). Additionally, chemical inhibition of NFκB activation with TPCA-1 (which inhibits the upstream kinase IKK-2) attenuated MCEC migration (N=4, P&lt;0.0001) and angiogenesis (N=6, P&lt;0.005), as compared with untreated cells. Angiogenesis assessed by aortic ring sprouting was increased in Usp20 -/- compared with WT specimens (males, N=3, P&lt;0.0001; females, N=2, P&lt;0.0001), and it was also suppressed by TPCA-1 (males, N=2, WT; N=3 Usp20 -/- , P&lt;0.0001; females, N=2 WT; N=3, Usp20 -/- P&lt;0.0005). Angiogenesis was enhanced in aortic rings from USP20(S334D) CRISPR/Cas9 gene-edited mice (males, N=3, P&lt;0.01; females, N=3 WT &amp; N=4, USP20(S334D) P&lt;0.0001), but reduced in aortic rings from USP20(S334A) mice (males, N=3, P&lt;0.05; females, N=3 WT &amp; N=5 USP20(S334A) P&lt;0.0001). We conclude that preserving EC USP20 activity by preventing phosphorylation of USP20 on Ser 334 diminishes endothelial activation and angiogenic sprouting, which can decrease atherosclerosis.