Inhibition of RelA-Ser536 phosphorylation by a competing peptide reduces mouse liver fibrosis without blocking the innate immune response

Subcellular Fractionation and Metaproteogenomic Identification and Validation of Key Differentially Expressed Molecular Targets for Keloid Disease

Keloid disease (KD) is a common connective tissue disorder of unknown aetiopathogenesis with ill-defined treatment. Keloid scars present as exophytic fibroproliferative reticular lesions postcutaneous injury, and even though KD remains neoplastically benign, keloid lesions behave locally aggressive, invasive and expansive. To date, there is limited understanding and validation of biomarkers identified through combined proteomic and genomic evaluation of KD. Therefore, the aim in this study was to identify putative causative candidates in KD by performing a comprehensive proteomics analysis of subcellular fractions as well as the whole cell, coupled with transcriptomics data analysis of normal compared with KD fibroblasts. We then applied novel integrative bioinformatics analysis to demonstrate that NF-kB-p65 (RELA) from the cytosolic fraction and CAPN2 from the whole-cell lysate were statistically significantly upregulated in KD and associated with alterations in relevant key signaling pathways, including apoptosis. Our findings were further confirmed by showing upregulation of both RELA and CAPN2 in KD using flow cytometry and immunohistochemistry. Moreover, functional evaluation using real-time cell analysis and flow cytometry demonstrated that both omeprazole and dexamethasone inhibited the growth of KD fibroblasts by enhancing the rate of apoptosis. In conclusion, subcellular fractionation and metaproteogenomic analyses have identified, to our knowledge, 2 previously unreported biomarkers of significant relevance to keloid diagnostics and therapeutics.

Two sides of the same coin: Non-alcoholic fatty liver disease and atherosclerosis

The prevalence of non-alcoholic fatty liver disease (NAFLD) and atherosclerosis remain high, which is primarily due to widespread adoption of a western diet and sedentary lifestyle. NAFLD, together with advanced forms of this disease such as non-alcoholic steatohepatitis (NASH) and cirrhosis, are closely associated with atherosclerotic-cardiovascular disease (ASCVD). In this review, we discussed the association between NAFLD and atherosclerosis and expounded on the common molecular biomarkers underpinning the pathogenesis of both NAFLD and atherosclerosis. Furthermore, we have summarized the mode of function and potential clinical utility of existing drugs in the context of these diseases.

Targeting CD301+ macrophages inhibits endometrial fibrosis and improves pregnancy outcome

Macrophages are a key and heterogeneous cell population involved in endometrial repair and regeneration during the menstrual cycle, but their role in the development of intrauterine adhesion (IUA) and sequential endometrial fibrosis remains unclear. Here, we reported that CD301+ macrophages were significantly increased and showed their most active interaction with profibrotic cells in the endometria of IUA patients compared with the normal endometria by single-cell RNA sequencing, bulk RNA sequencing, and experimental verification. Increasing CD301+ macrophages promoted the differentiation of endometrial stromal cells into myofibroblasts and resulted in extracellular matrix accumulation, which destroyed the physiological architecture of endometrial tissue, drove endometrial fibrosis, and ultimately led to female infertility or adverse pregnancy outcomes. Mechanistically, CD301+ macrophages secreted GAS6 to activate the AXL/NF-κB pathway, upregulating the profibrotic protein synthesis. Targeted deletion of CD301+ macrophages or inhibition of AXL by Bemcentinib blunted the pathology and improved the outcomes of pregnancy in mice, supporting the therapeutic potential of targeting CD301+ macrophages for treating endometrial fibrosis.

Active ingredients screening and pharmacological mechanism research of curcumae rhizoma-sparganii rhizoma herb pair ameliorates liver fibrosis based on network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Curcumae Rhizoma-Sparganii Rhizoma (CR-SR) is a classic herbal pair to promote blood circulation and remove blood stasis in ancient China. However, the molecular mechanism is still unclear.

AIM OF STUDY

To screen out the anti-liver fibrosis active ingredients in CR-SR. Moreover, preliminary exploration the molecular mechanism of CR-SR to ameliorates liver fibrosis.

MATERIALS AND METHODS

In this research, plant taxonomy has been confirmed in the "The Plant List" database (www.theplantlist.org). The chemical components of CR-SR were analysed by ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UPLC-Q/TOF-MS). "Component-Target-Pathway-Disease" network of CR-SR components were built by network pharmacology. Then, the interaction between primary components and predicted protein targets based on network pharmacology were validated by molecular docking. The pharmacological actions of CR-SR were verified by blood biochemical indexes, histopathologic examination of CCL₄ induced rats' model. The core protein targets were verified by Western blot. The effects of screened active components by molecular autodocking were verified by HSC-T6 cell experiment.

RESULTS

The result shows that 57 chemical constituents in CR-SR herbal pair were identified by UPLC-Q/TOF-MS, in which, 27 compounds were closely connected with liver fibrosis related protein targets. 55 protein targets screened out by "component-target-pathway-disease network" maybe the underlying targets for CR-SR to cure liver fibrosis. Moreover, the 55 protein targets are mainly related to RNA transcription, apoptosis, and signal transduction. The molecular autodocking predicted that ten components can bond well with PTGS2 and RELA protein targets. The blood biochemical indexes, histopathologic examination of CCL₄ induced rats experiment showed that CR-SR has well intervention effect of liver fibrosis. The Western blot analysis indicated that CR-SR could significantly inhibit RELA, PTGS2, IL-6, SRC, and AKT1 protein expression to exert the anti-fibrosis effect. The HSC-T6 cell experiment indicated that both formononetin (FNT) and curdione could significantly inhibit the activation of HSC and reduce the expression of PTGS2, and p-AKT1 which was accordance with the molecular autodocking results.

CONCLUSION

This study proved the molecular mechanism of CR-SR multi-component and multi-target anti-liver fibrosis effect through mass spectrometry, network pharmacology, and western blotting technology. The research provides a theoretical evidence for the development and utilization of CR-SR herbal pair.

Defining the spatial-molecular map of fibrotic tendon healing and the drivers of Scleraxis-lineage cell fate and function

Tendon injuries heal via a scar-mediated response, and there are no biological approaches to promote more regenerative healing. Mouse flexor tendons heal through the formation of spatially distinct tissue areas: a highly aligned tissue bridge between the native tendon stubs that is enriched for adult Scleraxis-lineage cells and a disorganized outer shell associated with peri-tendinous scar formation. However, the specific molecular programs that underpin these spatially distinct tissue profiles are poorly defined. In the present study, we combine lineage tracing of adult Scleraxis-lineage cells with spatial transcriptomic profiling to define the overarching molecular programs that govern tendon healing and cell-fate decisions. Pseudotime analysis identified three fibroblast trajectories (synthetic, fibrotic, and reactive) and key transcription factors regulating these fate-switching decisions, including the progression of adult Scleraxis-lineage cells through the reactive trajectory. Collectively, this resource defines the molecular mechanisms that coordinate the temporo-spatial healing phenotype, which can be leveraged to inform therapeutic candidate selection.

Study on the Mechanism of Astragalus Polysaccharide in Treating Pulmonary Fibrosis Based on "Drug-Target-Pathway" Network

Pulmonary fibrosis is a chronic, progressive and irreversible heterogeneous disease of pulmonary interstitial tissue. Its incidence is increasing year by year in the world, and it will be further increased due to the pandemic of COVID-19. However, at present, there is no safe and effective treatment for this disease, so it is very meaningful to find drugs with high efficiency and less adverse reactions. The natural astragalus polysaccharide has the pharmacological effect of anti-pulmonary fibrosis with little toxic and side effects. At present, the mechanism of anti-pulmonary fibrosis of astragalus polysaccharide is not clear. Based on the network pharmacology and molecular docking method, this study analyzes the mechanism of Astragalus polysaccharides in treating pulmonary fibrosis, which provides a theoretical basis for its further clinical application. The active components of Astragalus polysaccharides were screened out by Swisstarget database, and the related targets of pulmonary fibrosis were screened out by GeneCards database. Protein-protein interaction network analysis and molecular docking were carried out to verify the docking affinity of active ingredients. At present, through screening, we have obtained 92 potential targets of Astragalus polysaccharides for treating pulmonary fibrosis, including 11 core targets. Astragalus polysaccharides has the characteristics of multi-targets and multi-pathways, and its mechanism of action may be through regulating the expression of VCAM1, RELA, CDK2, JUN, CDK1, HSP90AA1, NOS2, SOD1, CASP3, AHSA1, PTGER3 and other genes during the development of pulmonary fibrosis.

ZCL-082, a boron-containing compound, induces apoptosis of non-Hodgkin's lymphoma via targeting p90 ribosomal S6 kinase 1/NF-κB signaling pathway

INTRODUCTION

Despite the rapid progress in the diagnosis and treatment, the prognosis of some types of non-Hodgkin's lymphoma (NHL), especially those with double-hit or double-expressor genotypes, remains poor. Novel targets and compounds are needed to improve the prognosis of NHL.

METHODS

We investigated the effect of ZCL-082, a novel boron-containing compound with anti-proliferating activity against ovarian cancer cells, on NHL cells and human peripheral blood mononuclear cells by CCK-8 assay, Annexin V/PI double staining assay, RH123/PI double staining, Western blot, and immunohistochemistry. NF-κB pathway activity was analyzed using luciferase reporter gene assay and RT-PCR. The location of p65 was detected by immunofluorescence and nuclear/cytoplasmic fractionation assay. Immunoprecipitation and chromatin immunoprecipitation assays were used to detect the binding between p65 and p300. CETSA and molecular docking assay were carried out to test the interaction between ZCL-082 and p90 ribosomal S6 kinase 1 (RSK1). Kinase reaction was conducted to examine the inhibition of RSK1 kinase activity by ZCL-082.

RESULTS

We found that ZCL-082 can induce the apoptosis of various NHL cell lines in vitro and in vivo. ZCL-082 significantly inhibits TNFα- or LPS-induced NF-κB activation without disturbing TNFα-induced IκBα degradation or the nuclear translocation and DNA-binding ability of p65. However, ZCL-082 markedly suppresses the phosphorylation of p65 on Ser536 and the interaction between p65 and p300. The overexpression of the phosphomimetic mutant of p65 at Ser536 partially abrogates ZCL-082-induced cell death. We further found that ZCL-082 directly binds to and inhibits the activity of RSK1. RSK1 can phosphorylate RelA/p65 on Ser536 and its overexpression is associated with the poor prognosis of lymphoma. The overexpression of RSK1 partially rescues ZCL-082-induced cell death. Molecular docking studies show that ZCL-082 fits well with the N-terminal kinase domain of RSK1. Furthermore, the combination of ZCL-082 and BCL-2 inhibitor ABT-199 has a synergistic apoptosis-inducing effect against double-hit lymphoma cell line OCI-Ly10.

DISCUSSION

We found that ZCL-082 is a highly promising anti-lymphoma compound that targets RSK1 and interferes with the RSK1/NF-κB signaling pathway. The combination of ZCL-082 with BCL-2 inhibitor may represent a novel strategy to improve the outcome of double-hit or double-expressor lymphoma.

Deciphering the Role of Innate Immune NF-ĸB Pathway in Pancreatic Cancer

Simple Summary

Chronic inflammation is a major mechanism that underlies the aggressive nature and treatment resistance of pancreatic cancer. In many ways, the molecular mechanisms that drive chronic inflammation in pancreatic cancer are very similar to our body’s normal innate immune response to injury or invading microorganisms. Therefore, during cancer development, pancreatic cancer cells hijack the innate immune pathway to foster a chronically inflamed tumor environment that helps shield them from immune attack and therapeutics. While blocking the innate immune pathway is theoretically reasonable, untoward side effects must also be addressed. In this review, we comprehensively summarize the literature that describe the role of innate immune signaling in pancreatic cancer, emphasizing the specific role of this pathway in different cell types. We review the interaction of the innate immune pathway and cancer-driving signaling in pancreatic cancer and provide an updated overview of novel therapeutic opportunities against this mechanism.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with no effective treatment option. A predominant hallmark of PDAC is the intense fibro-inflammatory stroma which not only physically collapses vasculature but also functionally suppresses anti-tumor immunity. Constitutive and induced activation of the NF-κB transcription factors is a major mechanism that drives inflammation in PDAC. While targeting this pathway is widely supported as a promising therapeutic strategy, clinical success is elusive due to a lack of safe and effective anti-NF-κB pathway therapeutics. Furthermore, the cell type-specific contribution of this pathway, specifically in neoplastic cells, stromal fibroblasts, and immune cells, has not been critically appraised. In this article, we highlighted seminal and recent literature on molecular mechanisms that drive NF-κB activity in each of these major cell types in PDAC, focusing specifically on the innate immune Toll-like/IL-1 receptor pathway. We reviewed recent evidence on the signaling interplay between the NF-κB and oncogenic KRAS signaling pathways in PDAC cells and their collective contribution to cancer inflammation. Lastly, we reviewed clinical trials on agents that target the NF-κB pathway and novel therapeutic strategies that have been proposed in preclinical studies.

MicroRNA-21-3p Engineered Umbilical Cord Stem Cell-Derived Exosomes Inhibit Tendon Adhesion

Purpose

As a common complication of tendon injury, tendon adhesion is an unresolved problem in clinical work. The aim of this study was to investigate whether human umbilical cord mesenchymal stem cell-derived exosomes (HUMSC-Exos), one of the most promising new-generation cell-free therapeutic agents, can improve tendon adhesion and explore potential-related mechanisms.

Methods

The rat Achilles tendon injury adhesion model was constructed in vivo, and the localization of HUMSC-Exos was used to evaluate the tendon adhesion. Rat fibroblast cell lines were treated with transforming growth factor β1 (TGF-β1) and/or HUMSC-Exos in vitro, and cell proliferation, apoptosis and gene expression were measured. MicroRNA (miRNA) sequencing and quantitative PCR (qPCR) analysis confirmed differential miRNAs. A specific miRNA antagonist (antagomir-21a-5p) was used to transform HUMSC-Exos and obtain modified exosomes to verify its efficacy and related mechanism of action.

Results

In this study, we found HUMSC-Exos reduced rat fibroblast proliferation and inhibited the expression of fibrosis genes: collagen III (COL III) and α-smooth muscle actin (α-SMA) in vitro. In the rat tendon adhesion model, topical application of HUMSC-Exos contributed to relief of tendon adhesion. Specifically, the fibrosis and inflammation-related genes were simultaneously inhibited by HUMSC-Exos. Further, miRNA sequencing of HUMSCs and HUMSC-Exos showed that miR-21a-3p was expressed at low abundance in HUMSC-Exos. The antagonist targeting miR-21a-3p was recruited for treatment of HUMSCs, and harvested HUMSC-Exos, which expressed low levels of miR-21a-3p, and expanded the inhibition of tendon adhesion in subsequent in vitro experiments.

Conclusion

Our results indicate that HUMSC-Exos may manipulate p65 activity by delivering low-abundance miR-21a-3p, ultimately inhibiting tendon adhesion. The findings may be promising for dealing with tendon adhesion.

The cellular and molecular basis of major depressive disorder: towards a unified model for understanding clinical depression

Major depressive disorder (MDD) is considered a serious public health issue that adversely impacts an individual's quality of life and contributes significantly to the global burden of disease. The clinical heterogeneity that exists among patients limits the ability of MDD to be accurately diagnosed and currently, a symptom-based approach is utilized in many cases. Due to the complex nature of this disorder, and lack of precise knowledge regarding the pathophysiology, effective management is challenging. The aetiology and pathophysiology of MDD remain largely unknown given the complex genetic and environmental interactions that are involved. Nonetheless, the aetiology and pathophysiology of MDD have been the subject of extensive research, and there is a vast body of literature that exists. Here we overview the key hypotheses that have been proposed for the neurobiology of MDD and highlight the need for a unified model, as many of these pathways are integrated. Key pathways discussed include neurotransmission, neuroinflammation, clock gene machinery pathways, oxidative stress, role of neurotrophins, stress response pathways, the endocannabinoid and endovanilloid systems, and the endogenous opioid system. We also describe the current management of MDD, and emerging novel therapies, with particular focus on patients with treatment-resistant depression (TRD).

Identification of a novel TIF-IA-NF-κB nucleolar stress response pathway

p53 as an effector of nucleolar stress is well defined, but p53 independent mechanisms are largely unknown. Like p53, the NF-κB transcription factor plays a critical role in maintaining cellular homeostasis under stress. Many stresses that stimulate NF-κB also disrupt nucleoli. However, the link between nucleolar function and activation of the NF-κB pathway is as yet unknown. Here we demonstrate that artificial disruption of the PolI complex stimulates NF-κB signalling. Unlike p53 nucleolar stress response, this effect does not appear to be linked to inhibition of rDNA transcription. We show that specific stress stimuli of NF-κB induce degradation of a critical component of the PolI complex, TIF-IA. This degradation precedes activation of NF-κB and is associated with increased nucleolar size. It is mimicked by CDK4 inhibition and is dependent upon a novel pathway involving UBF/p14ARF and S44 of the protein. We show that blocking TIF-IA degradation blocks stress effects on nucleolar size and NF-κB signalling. Finally, using ex vivo culture, we show a strong correlation between degradation of TIF-IA and activation of NF-κB in freshly resected, human colorectal tumours exposed to the chemopreventative agent, aspirin. Together, our study provides compelling evidence for a new, TIF-IA-NF-κB nucleolar stress response pathway that has in vivo relevance and therapeutic implications.

Context-Dependent Role of NF-κB Signaling in Primary Liver Cancer-from Tumor Development to Therapeutic Implications

Chronic inflammatory cell death is a major risk factor for the development of diverse cancers including liver cancer. Herein, disruption of the hepatic microenvironment as well as the immune cell composition are major determinants of malignant transformation and progression in hepatocellular carcinomas (HCC). Considerable research efforts have focused on the identification of predisposing factors that promote induction of an oncogenic field effect within the inflammatory liver microenvironment. Among the most prominent factors involved in this so-called inflammation-fibrosis-cancer axis is the NF-κB pathway. The dominant role of this pathway for malignant transformation and progression in HCC is well documented. Pathway activation is significantly linked to poor prognostic traits as well as stemness characteristics, which places modulation of NF-κB signaling in the focus of therapeutic interventions. However, it is well recognized that the mechanistic importance of the pathway for HCC is highly context and cell type dependent. While constitutive pathway activation in an inflammatory etiological background can significantly promote HCC development and progression, absence of NF-κB signaling in differentiated liver cells also significantly enhances liver cancer development. Thus, therapeutic targeting of NF-κB as well as associated family members may not only exert beneficial effects but also negatively impact viability of healthy hepatocytes and/or cholangiocytes, respectively. The review presented here aims to decipher the complexity and paradoxical functions of NF-κB signaling in primary liver and non-parenchymal cells, as well as the induced molecular alterations that drive HCC development and progression with a particular focus on (immune-) therapeutic interventions.

Epstein-Barr virus tegument protein BGLF2 inhibits NF-κB activity by preventing p65 Ser536 phosphorylation

Epstein-Barr virus (EBV), a ubiquitous gammaherpesvirus, can regulate the antiviral response of NF-κB signaling, which is critical for cell survival, growth transformation, and virus latency. Here, we showed that tegument protein BGLF2 could inhibit TNF-α-induced NF-κB activity. BGLF2 was shown to interplay with the NF-κB subunits p65 and p50, and the Rel homology domain of p65 was the pivotal region to interact with BGLF2. Nonetheless, BGLF2 did not influence the development of p65-p50 dimerization. Yet, overexpression of BGLF2 inhibited the phosphorylation of p65 Ser536 (but not Ser276) and blocked the nuclear translocation of p65. In addition, knockdown of BGLF2 during EBV lytic replication elevated NF-κB activity and the phosphorylation of p65 Ser536. Taken together, these results suggest that the inhibition of NF-κB activation may serve as a strategy to escape the host's antiviral innate immunity to EBV during its lytic infection.-Chen, T., Wang, Y., Xu, Z., Zou, X., Wang, P., Ou, X., Li, Y., Peng, T., Chen, D., Li, M., Cai, M. Epstein-Barr virus tegument protein BGLF2 inhibits NF-κB activity by preventing p65 Ser536 phosphorylation.

MicroRNA-26a/Death-Associated Protein Kinase 1 Signaling Induces Synucleinopathy and Dopaminergic Neuron Degeneration in Parkinson's Disease

BACKGROUND

Death-associated protein kinase 1 (DAPK1) is a widely distributed serine/threonine kinase that is critical for cell death in multiple neurological disorders, including Alzheimer's disease and stroke. However, little is known about the role of DAPK1 in the pathogenesis of Parkinson's disease (PD), the second most common neurodegenerative disorder.

METHODS

We used Western blot and immunohistochemistry to evaluate the alteration of DAPK1. Quantitative polymerase chain reaction and fluorescence in situ hybridization were used to analyze the expression of microRNAs in PD mice and patients with PD. Rotarod, open field, and pole tests were used to evaluate the locomotor ability. Immunofluorescence, Western blot, and filter traps were used to evaluate synucleinopathy in PD mice.

RESULTS

We found that DAPK1 is posttranscriptionally upregulated by a reduction in microRNA-26a (miR-26a) caused by a loss of the transcription factor CCAAT enhancer-binding protein alpha. The overexpression of DAPK1 in PD mice is positively correlated with neuronal synucleinopathy. Suppressing miR-26a or upregulating DAPK1 results in synucleinopathy, dopaminergic neuron cell death, and motor disabilities in wild-type mice. In contrast, genetic deletion of DAPK1 in dopaminergic neurons by crossing DAT-Cre mice with DAPK1 floxed mice effectively rescues the abnormalities in mice with chronic MPTP treatment. We further showed that DAPK1 overexpression promotes PD-like phenotypes by direct phosphorylation of α-synuclein at the serine 129 site. Correspondingly, a cell-permeable competing peptide that blocks the phosphorylation of α-synuclein prevents motor disorders, synucleinopathy, and dopaminergic neuron loss in the MPTP mice.

CONCLUSIONS

miR-26a/DAPK1 signaling cascades are essential in the formation of the molecular and cellular pathologies in PD.

Transplantation of bone marrow mesenchymal stromal cells attenuates liver fibrosis in mice by regulating macrophage subtypes

Background

Liver fibrosis is a key phase that will progress to further injuries such as liver cirrhosis or carcinoma. This study aimed to investigate whether transplantation of bone marrow mesenchymal stromal cells (BM-MSCs) can attenuate liver fibrosis in mice and the underlying mechanisms based on the regulation of macrophage subtypes.

Methods

A liver fibrosis model was induced by intraperitoneal (i.p.) injection of CCl4 twice per week for 70 days, and BM-MSCs were intravenously transplanted twice on the 60th and 70th days. Immunohistology and gene expression of liver fibrosis and macrophage subtypes were analyzed. Mouse RAW264.7 cells and JS1 cells (hepatic stellate cell strain) were also used to explore the underlying mechanisms of the effects of BM-MSCs on liver fibrosis.

Results

After transplantation of BM-MSCs, F4/80⁺CD206⁺-activated M2 macrophages and matrix metalloproteinase 13 (MMP 13) expression were significantly increased while F4/80⁺iNOS⁺-activated M1 macrophages were inhibited in liver tissue. Gene expression of IL-10 was elevated while IL12b, IFN-γ, TNF-α, and IL-6 gene expression were decreased. ΤGF-β1 and collagen-1 secretions were reduced while caspase-3 was increased in JS1 cells treated with BM-MSC-conditioned media. BM-MSCs effectively suppressed the expression of α-SMA, Sirius red, and collagen-1 in the liver, which are positively correlated with fibrosis and induced by CCl4 injection.

Conclusions

Taken together, we have provided the first demonstration that BM-MSC transplantation can promote the activation of M2 macrophages expressing MMP13 and inhibition of M1 macrophages to further inhibit hepatic stellate cells (HSCs), which play synergistic roles in attenuating liver fibrosis.

The cirrhotic liver is depleted of docosahexaenoic acid (DHA), a key modulator of NF-κB and TGFβ pathways in hepatic stellate cells

Liver cirrhosis results from chronic hepatic damage and is characterized by derangement of the organ architecture with increased liver fibrogenesis and defective hepatocellular function. It frequently evolves into progressive hepatic insufficiency associated with high mortality unless liver transplantation is performed. We have hypothesized that the deficiency of critical nutrients such as essential omega-3 fatty acids might play a role in the progression of liver cirrhosis. Here we evaluated by LC-MS/MS the liver content of omega-3 docosahexaenoic fatty acid (DHA) in cirrhotic patients and investigated the effect of DHA in a murine model of liver injury and in the response of hepatic stellate cells (HSCs) (the main producers of collagen in the liver) to pro-fibrogenic stimuli. We found that cirrhotic livers exhibit a marked depletion of DHA and that this alteration correlates with the progression of the disease. Administration of DHA exerts potent anti-fibrogenic effects in an acute model of liver damage. Studies with HSCs show that DHA inhibits fibrogenesis more intensely than other omega-3 fatty acids. Data from expression arrays revealed that DHA blocks TGFβ and NF-κB pathways. Mechanistically, DHA decreases late, but not early, SMAD3 nuclear accumulation and inhibits p65/RelA-S536 phosphorylation, which is required for HSC survival. Notably, DHA increases ADRP expression, leading to the formation of typical quiescence-associated perinuclear lipid droplets. In conclusion, a marked depletion of DHA is present in the liver of patients with advanced cirrhosis. DHA displays anti-fibrogenic activities on HSCs targeting NF-κB and TGFβ pathways and inducing ADPR expression and quiescence in these cells.

Dysfunctional Mechanism of Liver Cancer Mediated by Transcription Factor and Non-coding RNA

Background:

There have been numerous experiments and studies on liver cancer by biomedical scientists, while no comprehensive and systematic exploration has yet been conducted. Therefore, this study aimed to systematically dissect the transcriptional and non-coding RNAmediated mechanisms of liver cancer dysfunction.

Method:

At first, we collected 974 liver cancer associated genes from the Online Mendelian Inheritance in Man (OMIM). Afterwards, their interactors were recruited from STRING database so as to identify 18 co-expression modules in liver cancer patient expression profile. Crosstalk analysis showed the interactive relationship between these modules. In addition, core drivers for modules were identified, including 111 transcription factors (STAT3, JUN and NFKB1, etc.) and 1492 ncRNAs (FENDRR and miR-340-5p, etc.).

Results:

In view of the results of enrichment, we found that these core drivers were significantly involved in Notch signaling, Wnt / β-catenin pathways, cell proliferation, apoptosis-related functions and pathways, suggesting they can affect the development of liver cancer. Furthermore, a global effect on bio-network associated with liver cancer has been integrated from the ncRNA and TF pivot network, module crosstalk network, module-function/pathways network. It involves various development and progression of cancer.

Conclusion:

Overall, our analysis further suggests that comprehensive network analysis will help us to not only understand in depth the molecular mechanisms, but also reveal the influence of related gene dysfunctional modules on the occurrence and progression of liver cancer. It provides a valuable reference for the design of liver cancer diagnosis and treatment.

Annexin A5 suppresses cyclooxygenase-2 expression by downregulating the protein kinase C-ζ-nuclear factor-κB signaling pathway in prostate cancer cells

Annexin A5 (ANXA5) is a member of the annexin protein family. Previous studies have shown that ANXA5 is involved in anti-inflammation and cell death. However, the detailed mechanism of the role of ANXA5 in cancer cells is not well understood. In this study, we investigated the inhibitory effect of ANXA5 on cyclooxygenase-2 (COX-2) in prostate cancer cells. Expression of COX-2 induced by TNF-α was inhibited by overexpression of ANXA5 and inhibition of COX-2 expression by auranofin, which could induce ANXA5 expression, was restored by ANXA5 knockdown. In addition, ANXA5 knockdown induces phosphorylation of NF-κB p65 in prostate cancer cells, indicating that ANXA5 causes COX-2 downregulation through inhibition of p65 activation. We also found that protein kinase C (PKC)-ζ protein levels were upregulated by the inhibition of ANXA5, although the mRNA levels were unaffected. We have shown that upregulated COX-2 expression by inhibition of ANXA5 is attenuated by PKC-ζ siRNA. In summary, this study demonstrates that downregulation of PKC-ζ-NF-κB signaling by ANXA5 may inhibit COX-2 expression in prostate cancer.

RelA/p65 inhibition prevents tendon adhesion by modulating inflammation, cell proliferation, and apoptosis

Peritendinous tissue fibrosis which leads to poor tendon function is a worldwide clinical problem; however, its mechanism remains unclear. Transcription factor RelA/p65, an important subunit in the NF-κB complex, is known to have a critical role in many fibrotic diseases. Here, we show that RelA/p65 functions as a core fibrogenic regulator in tendon adhesion and that its inhibition exerts an anti-fibrogenic effect on peritendinous adhesion. We detected the upregulation of the NF-κB pathway in human tendon adhesion using a gene chip microarray assay and revealed the overexpression of p65 and extracellular matrix (ECM) proteins Collagen I, Collagen III, and α-smooth muscle actin (α-SMA) in human fibrotic tissues by immunohistochemistry and western blotting. We also found that in a rat model of tendon injury, p65 expression correlated with tendon adhesion, whereas its inhibition by small interfering (si)RNA prevented fibrous tissue formation and inflammatory reaction as evidenced by macroscopic, biomechanical, histological, immunohistochemical, and western blotting analyses. Furthermore, in cultured fibroblasts, p65-siRNA, p65-specific inhibitor, Helenalin and JSH23 suppressed cell proliferation and promoted apoptosis, whereas inhibiting the mRNA and protein expression of ECM components and cyclo-oxygenase-2, an inflammatory factor involved in tendon adhesion. Our findings indicate that p65 has a critical role in peritendinous tissue fibrosis and suggest that p65 knockdown may be a promising therapeutic approach to prevent tendon adhesion.

Negative regulation of NF-κB p65 activity by serine 536 phosphorylation

Nuclear factor κB (NF-κB) is a master regulator of inflammation and cell death. Whereas most of the activity of NF-κB is regulated through the inhibitor of κB (IκB) kinase (IKK)-dependent degradation of IκB, IKK also phosphorylates subunits of NF-κB. We investigated the contribution of the phosphorylation of the NF-κB subunit p65 at the IKK phosphorylation site serine 536 (Ser(536)) in humans, which is thought to be required for the activation and nuclear translocation of NF-κB. Through experiments with knock-in mice (S534A mice) expressing a mutant p65 with an alanine-to-serine substitution at position 534 (the murine homolog of human Ser(536)), we observed increased expression of NF-κB-dependent genes after injection of mice with the inflammatory stimulus lipopolysaccharide (LPS) or exposure to gamma irradiation, and the enhanced gene expression was most pronounced at late time points. Compared to wild-type mice, S534A mice displayed increased mortality after injection with LPS. Increased NF-κB signaling in the S534A mice was at least in part explained by the increased stability of the S534A p65 protein compared to that of the Ser(534)-phosphorylated wild-type protein. Together, our results suggest that Ser(534) phosphorylation of p65 in mice (and, by extension, Ser(536) phosphorylation of human p65) is not required for its nuclear translocation, but instead inhibits NF-κB signaling to prevent deleterious inflammation.

Molecular Pathways: The Balance between Cancer and the Immune System Challenges the Therapeutic Specificity of Targeting Nuclear Factor-κB Signaling for Cancer Treatment

The NF-κB signaling pathway is a complex network linking extracellular stimuli to cell survival and proliferation. Cytoplasmic signaling to activate NF-κB can occur as part of the DNA damage response or in response to a large variety of activators, including viruses, inflammation, and cell death. NF-κB transcription factors play a fundamental role in tumorigenesis and are implicated in the origination and propagation of both hematologic and solid tumor types, including melanoma, breast, prostate, ovarian, pancreatic, colon, lung, and thyroid cancers. On the other hand, NF-κB signaling is key to immune function and is likely necessary for antitumor immunity. This presents a dilemma when designing therapeutic approaches to target NF-κB. There is growing interest in identifying novel modulators to inhibit NF-κB activity as impeding different steps of the NF-κB pathway has potential to slow tumor growth, progression, and resistance to chemotherapy. Despite significant advances in our understanding of this pathway, our ability to effectively clinically block key targets for cancer therapy remains limited due to on-target effects in normal tissues. Tumor specificity is critical to developing therapeutic strategies targeting this antiapoptotic signaling pathway to maintain antitumor immune surveillance when applying such therapy to patients. Clin Cancer Res; 22(17); 4302-8. ©2016 AACR.

Developmental Biology and Regenerative Medicine: Addressing the Vexing Problem of Persistent Muscle Atrophy in the Chronically Torn Human Rotator Cuff

Persistent muscle atrophy in the chronically torn rotator cuff is a significant obstacle for treatment and recovery. Large atrophic changes are predictive of poor surgical and nonsurgical outcomes and frequently fail to resolve even following functional restoration of loading and rehabilitation. New insights into the processes of muscle atrophy and recovery gained through studies in developmental biology combined with the novel tools and strategies emerging in regenerative medicine provide new avenues to combat the vexing problem of muscle atrophy in the rotator cuff. Moving these treatment strategies forward likely will involve the combination of surgery, biologic/cellular agents, and physical interventions, as increasing experimental evidence points to the beneficial interaction between biologic therapies and physiologic stresses. Thus, the physical therapy profession is poised to play a significant role in defining the success of these combinatorial therapies. This perspective article will provide an overview of the developmental biology and regenerative medicine strategies currently under investigation to combat muscle atrophy and how they may integrate into the current and future practice of physical therapy.

Heat shock protein 20 (HSPB6) regulates TNF-α-induced intracellular signaling pathway in human hepatocellular carcinoma cells

We previously demonstrated that the expression of HSP20, a small heat shock protein, is inversely correlated with the progression of HCC. Inflammation is associated with HCC, and numerous cytokines, including TNF-α, act as key mediators in the progression of HCC. In the present study, we investigated whether HSP20 is implicated in the TNF-α-stimulated intracellular signaling in HCC using human HCC-derived HuH7 cells in the presence of TNF-α. In HSP20-overexpressing HCC cells, the cell growth was retarded compared with that in the control cells under long-term exposure of TNF-α. Because NF-κB pathway is the main intracellular signaling system activated by TNF-α, we investigated the effects of HSP20-overexpression of this pathway. The protein levels of IKK-α, but not IKK-β, in the HSP20-overexpressing cells were decreased. Short-term exposure to TNF-α-induced phosphorylation and degradation of IκB, and the phosphorylation and transactivational activity of NF-κB were suppressed in the HSP20-overexpressing HCC cells. Furthermore, the increase in IKK-α levels was accompanied by a decrease in the HSP20 levels in human HCC tissues. These findings strongly suggest that HSP20 might decrease the IKK-α protein level and that it down-regulates the TNF-α-stimulated intracellular signaling in HCC, thus resulting in the suppression of HCC progression.

TET3 mediates the activation of human hepatic stellate cells via modulating the expression of long non-coding RNA HIF1A-AS1

Activated Hepatic stellate cells (HSCs) play a critical role in liver fibrosis and a lot of efforts have been made to dissect the underlying mechanism involved in activation of HSCs. However, the underlying mechanism remains douteux up to now. In the present study, we found that TET3, one member of ten-eleven translocation (TET) protein family, reduced significantly in HSCs LX-2 activated by TGF-β1. To study the function of TET3 in activation of HSCs, knockdown was performed by RNA interference. Results showed that cell proliferation rise significantly and cell apoptosis reduce obviously after knockdown of TET3. Meanwhile, IHC showed that the expression of α-SMA rise significantly compared to control. These results indicated that TET3 is closely associated with the activation of HSCs. Further studies found that long non-coding RNA HIF1A-AS1 was reduced significantly in LX-2 cell after treatment with siRNA for TET3. The result hinted that TET3 activate HSCs through modulating the expression of HIF1A-AS1. To confirm this hypothesis, RNA interference was performed to silence the HIF1A-AS1. Results showed that HIF1A-AS1 silencing lead to enhancing in cell proliferation and declining apoptosis. Taken together, TET3 can mediate the activation of HSCs via modulating the expression of the long non-coding RNA HIF1A-AS1.

Toll like receptor 2 knock-out attenuates carbon tetrachloride (CCl4)-induced liver fibrosis by downregulating MAPK and NF-κB signaling pathways

Innate immune signaling associated with Toll-like receptors (TLRs) is a key pathway involved in the progression of liver fibrosis. In this study, we reported that TLR2 is required for hepatic fibrogenesis induced by carbon tetrachloride (CCl4). After CCl4 treatment, TLR2(-/-) mice had reduced liver enzyme levels, diminished collagen deposition, decreased inflammatory infiltration and impaired activation of hepatic stellate cells (HSCs) than wild type (WT) mice. Furthermore, after CCl4 treatment, TLR2(-/-) mice demonstrated downregulated expression of profibrotic and proinflammatory genes and impaired mitogen-activated protein kinases (MAPK) and nuclear factor kappa B (NF-κB) activation than WT mice. Collectively, our data indicate that TLR2 deficiency protects against CCl4-induced liver fibrosis.

The c-Rel subunit of NF-κB regulates epidermal homeostasis and promotes skin fibrosis in mice

The five subunits of transcription factor NF-κB have distinct biological functions. NF-κB signaling is important for skin homeostasis and aging, but the contribution of individual subunits to normal skin biology and disease is unclear. Immunohistochemical analysis of the p50 and c-Rel subunits within lesional psoriatic and systemic sclerosis skin revealed abnormal epidermal expression patterns, compared with healthy skin, but RelA distribution was unaltered. The skin of Nfkb1(-/-) and c-Rel(-/-) mice is structurally normal, but epidermal thickness and proliferation are significantly reduced, compared with wild-type mice. We show that the primary defect in both Nfkb1(-/-) and c-Rel(-/-) mice is within keratinocytes that display reduced proliferation both in vitro and in vivo. However, both genotypes can respond to proliferative stress, with 12-O-tetradecanoylphorbol-13-acetate-induced epidermal hyperproliferation and closure rates of full-thickness skin wounds being equivalent to those of wild-type controls. In a model of bleomycin-induced skin fibrosis, Nfkb1(-/-) and c-Rel(-/-) mice displayed opposite phenotypes, with c-Rel(-/-) mice being protected and Nfkb1(-/-) developing more fibrosis than wild-type mice. Taken together, our data reveal a role for p50 and c-Rel in regulating epidermal proliferation and homeostasis and a profibrogenic role for c-Rel in the skin, and identify a link between epidermal c-Rel expression and systemic sclerosis. Modulating the actions of these subunits could be beneficial for treating hyperproliferative or fibrogenic diseases of the skin.