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Initial symptoms of neurodegenerative diseases are often defined by the loss of the most vulnerable neural populations specific to each disorder. In the early stages of Alzheimer's disease, vulnerable circuits in the temporal lobe exhibit diminished activity prior to overt degeneration. It remains unclear whether these functional changes contribute to regional vulnerability or are simply a consequence of pathology. We previously found that entorhinal neurons in the temporal cortex undergo cell death following transient suppression of electrical activity, suggesting a causal role for activity disruption in neurodegeneration. Here we demonstrate that electrical arrest of this circuit stimulates the injury‐response transcription factor c‐Jun. Entorhinal silencing induces transcriptional changes consistent with c‐Jun activation that share characteristics of gene signatures in other neuronal populations vulnerable to Alzheimer's disease. Despite its established role in the neuronal injury response, inhibiting c‐Jun failed to ameliorate entorhinal degeneration following activity disruption. Finally, we present preliminary evidence of integrated stress response activity that may serve as an alternative hypothesis to what drives entorhinal degeneration after silencing. Our data demonstrate that c‐Jun is activated in response to neuronal silencing in the entorhinal cortex but is decoupled from subsequent neurodegeneration. [ABSTRACT FROM AUTHOR]

Background: Schwann cells (SCs) and their plasticity contribute to the peripheral nervous system's capacity for nerve regeneration after injury. The Egr2/Krox20 promoter antisense RNA (Egr2-AS) recruits chromatin remodeling complexes to inhibit Egr2 transcription following peripheral nerve injury. Methods: RNA-seq and ATAC-seq were performed on control cells, Lenti-GFP-transduced cells, and cells overexpressing Egr2-AS (Lenti-AS). Egr2 AS-RNA was cloned into the pLVX-DsRed-Express2-N1 lentiviral expression vector (Clontech, Mountain View, CA, USA), and the levels of AS-RNA expression were determined. Ezh2 and Wdr5 were immunoprecipitated from rat SCs and RT-qPCR was performed against AS-Egr2 RNA. ChIP followed by DNA purification columns was used to perform qPCR for relevant promoters. Hi-C, HiC-DC+, R, Bioconductor, and TOBIAS were used for significant and differential loop analysis, identifications of COREs and CORE-promotor loops, comparisons of TF activity at promoter sites, and identification of site-specific TF footprints. OnTAD was used to detect TADs, and Juicer was used to identify A/B compartments. Results: Here we show that a Neuregulin-ErbB2/3 signaling axis mediates binding of the Egr2-AS to YY1Ser184 and regulates its expression. Egr2-AS modulates the chromatin accessibility of Schwann cells and interacts with two distinct histone modification complexes. It binds to EZH2 and WDR5 and enables targeting of H3K27me3 and H3K4me3 to promoters of Egr2 and C-JUN, respectively. Expression of the Egr2-AS results in reorganization of the global chromatin landscape and quantitative changes in the loop formation and contact frequency at domain boundaries exhibiting enrichment for AP-1 genes. In addition, the Egr2-AS induces changes in the hierarchical TADs and increases transcription factor binding scores on an inter-TAD loop between a super-enhancer regulatory hub and the promoter of mTOR. Conclusions: Our results show that Neuregulin-ErbB2/3-YY1 regulates the expression of Egr2-AS, which mediates remodeling of the chromatin landscape in Schwann cells. [ABSTRACT FROM AUTHOR]

Abdominal aortic aneurysms (AAA) is a life-threatening disease and the incidence of AAA is still on the rise in recent years. Numerous studies suggest that dietary moderate consumption of polyphenol exerts beneficial effects on cardiovascular disease. Apigenin (API) is a promising dietary polyphenol and possesses potent beneficial effects on our body. Although our previous study revealed protective effects of API on experimental AAA formation, up till now few studies were carried out to further investigate its involved molecular mechanisms. In the present study, network pharmacology combined molecular docking and experimental validation was used to explore API-related therapeutic targets and mechanisms in the treatment of AAA. Firstly, we collected 202 API-related therapeutic targets and 2475 AAA-related pathogenetic targets. After removing duplicates, a total of 68 potential therapeutic targets were obtained. Moreover, 5 targets with high degree including TNF, ACTB, INS, JUN, and MMP9 were identified as core targets of API for treating AAA. In addition, functional enrichment analysis indicated that API exerted pharmacological effects in AAA by affecting versatile mechanisms, including apoptosis, inflammation, blood fluid dynamics, and immune modulation. Molecular docking results further supported that API had strong affinity with the above core targets. Furthermore, protein level of core targets and related pathways were evaluated in a Cacl2-induced AAA model by using western blot and immunohistochemistry. The experimental validation results demonstrated that API significantly attenuated phosphorylation of JUN and protein level of predicted core targets. Taken together, based on network pharmacological and experimental validation, our study systematically explored associated core targets and potential therapeutic pathways of API for AAA treatment, which could supply valuable insights and theoretical basis for AAA treatment. [ABSTRACT FROM AUTHOR]

Abstract Globoid cell leukodystrophy is a severe rare disorder characterized by white matter degradation, resulting in a progressive loss of physical and mental abilities and has extremely limited therapeutic interventions. Therefore, this study aimed to delve into the Globoid cell leukodystrophy associated intricate network of differentially expressed genes (p 1) to identify potential druggable targets and possible therapeutic interventions using small molecules. The disease-associated neuronal protein circuit was constructed and analyzed, identifying 53 nodes (minimum edge cutoff 1), among which five (FOS, FOSB, GDNF, GFRA1, and JUN) were discerned as potential core protein nodes. Although our research enumerates the potential small molecules to target various protein nodes in the proposed disease network, we particularly underscore T-5224 to inhibit c-Jun activity as JUN was identified as one of the pivotal elements within the disease-associated neuronal protein circuit. The evaluation of T-5224 binding energy (− 11.0 kcal/mol) from docking study revealed that the compound to exhibit a notable affinity towards Jun/CRE complex. Moreover, the structural integrity of complex was affirmed through comprehensive molecular dynamics simulations, indicating a stable hydrophilic interaction between T-5224 and the Jun/CRE complex, thereby enhancing protein compactness and reducing solvent accessibility. This binding energy was further substantiated by free binding analysis, revealing a substantial thermodynamics complex state (− 448.00 ± 41.73 kJ/mol). Given that this investigation is confined to a computational framework, we additionally propose a hypothetical framework to ascertain the feasibility of inhibiting the Jun/CRE complex with T-5224 against Globoid cell leukodystrophy, employing a combination of in vitro and in vivo methodologies as a prospective avenue of this study.

Filaggrin (FLG) is an essential structural protein expressed in differentiated keratinocytes. Insufficient FLG expression contributes to the pathogenesis of chronic inflammatory skin diseases. Saikosaponin A (SSA), a bioactive oleanane-type triterpenoid, exerts anti-inflammatory activity. However, the effects of topically applied SSA on FLG expression in inflamed skin remain unclear. This study aimed to evaluate the biological activity of SSA in restoring reduced FLG expression. The effect of SSA on FLG expression in HaCaT cells was assessed through various biological methods, including reverse transcription PCR, quantitative real-time PCR, immunoblotting, and immunofluorescence staining. TNFα and IFNγ decreased FLG mRNA, cytoplasmic FLG protein levels, and FLG gene promoter–reporter activity compared to the control groups. However, the presence of SSA restored these effects. A series of FLG promoter–reporter constructs were generated to investigate the underlying mechanism of the effect of SSA on FLG expression. Mutation of the AP1-binding site (mtAP1) in the −343/+25 FLG promoter–reporter abrogated the decrease in reporter activities caused by TNFα + IFNγ, suggesting the importance of the AP1-binding site in reducing FLG expression. The SSA treatment restored FLG expression by inhibiting the expression and nuclear localization of FRA1 and c-Jun, components of AP1, triggered by TNFα + IFNγ stimulation. The ERK1/2 mitogen-activated protein kinase signaling pathway upregulates FRA1 and c-Jun expression, thereby reducing FLG levels. The SSA treatment inhibited ERK1/2 activation caused by TNFα + IFNγ stimulation and reduced the levels of FRA1 and c-Jun proteins in the nucleus, leading to a decrease in the binding of FRA1, c-Jun, p-STAT1, and HDAC1 to the AP1-binding site in the FLG promoter. The effect of SSA was evaluated in an animal study using a BALB/c mouse model, which induces human atopic-dermatitis-like skin lesions via the topical application of dinitrochlorobenzene. Topically applied SSA significantly reduced skin thickening, immune cell infiltration, and the expression of FRA1, c-Jun, and p-ERK1/2 compared to the vehicle-treated group. These results suggest that SSA can effectively recover impaired FLG levels in inflamed skin by preventing the formation of the repressor complex consisting of FRA1, c-Jun, HDAC1, and STAT1. [ABSTRACT FROM AUTHOR]

TFEB and TFE3 (TFEB/3), key regulators of lysosomal biogenesis and autophagy, play diverse roles depending on cell type. This study highlights a hitherto unrecognized role of TFEB/3 crucial for peripheral nerve repair. Specifically, they promote the generation of progenitor-like repair Schwann cells after axonal injury. In Schwann cell-specific TFEB/3 double knock-out mice of either sex, the TFEB/3 loss disrupts the transcriptomic reprogramming that is essential for the formation of repair Schwann cells. Consequently, mutant mice fail to populate the injured nerve with repair Schwann cells and exhibit defects in axon regrowth, target reinnervation, and functional recovery. TFEB/3 deficiency inhibits the expression of injury-responsive repair Schwann cell genes, despite the continued expression of c-jun, a previously identified regulator of repair Schwann cell function. TFEB/3 binding motifs are enriched in the enhancer regions of injury-responsive genes, suggesting their role in repair gene activation. Autophagy-dependent myelin breakdown is not impaired despite TFEB/3 deficiency. These findings underscore a unique role of TFEB/3 in adult Schwann cells that is required for proper peripheral nerve regeneration. [ABSTRACT FROM AUTHOR]

Ribonucleotide reductase (RNR) is the rate-limiting enzyme in the synthesis of deoxyribonucleotides and the target of multiple chemotherapy drugs, including gemcitabine. We previously identified that inhibition of RNR in Ewing sarcoma tumors upregulates the expression levels of multiple members of the activator protein-1 (AP-1) transcription factor family, including c-Jun and c-Fos, and downregulates the expression of c-Myc. However, the broader functions and downstream targets of AP-1, which are highly context- and cell-dependent, are unknown in Ewing sarcoma tumors. Consequently, in this work, we used genetically defined models, transcriptome profiling, and gene-set -enrichment analysis to identify that AP-1 and EWS-FLI1, the driver oncogene in most Ewing sarcoma tumors, reciprocally regulate the expression of multiple extracellular-matrix proteins, including fibronectins, integrins, and collagens. AP-1 expression in Ewing sarcoma cells also drives, concurrent with these perturbations in gene and protein expression, changes in cell morphology and phenotype. We also identified that EWS-FLI1 dysregulates the expression of multiple AP-1 proteins, aligning with previous reports demonstrating genetic and physical interactions between EWS-FLI1 and AP-1. Overall, these results provide novel insights into the distinct, EWS-FLI1-dependent features of Ewing sarcoma tumors and identify a novel, reciprocal regulation of extracellular-matrix components by EWS-FLI1 and AP-1. [ABSTRACT FROM AUTHOR]

Globoid cell leukodystrophy is a severe rare disorder characterized by white matter degradation, resulting in a progressive loss of physical and mental abilities and has extremely limited therapeutic interventions. Therefore, this study aimed to delve into the Globoid cell leukodystrophy associated intricate network of differentially expressed genes (p < 0.05, |Fc|> 1) to identify potential druggable targets and possible therapeutic interventions using small molecules. The disease-associated neuronal protein circuit was constructed and analyzed, identifying 53 nodes (minimum edge cutoff 1), among which five (FOS, FOSB, GDNF, GFRA1, and JUN) were discerned as potential core protein nodes. Although our research enumerates the potential small molecules to target various protein nodes in the proposed disease network, we particularly underscore T-5224 to inhibit c-Jun activity as JUN was identified as one of the pivotal elements within the disease-associated neuronal protein circuit. The evaluation of T-5224 binding energy (− 11.0 kcal/mol) from docking study revealed that the compound to exhibit a notable affinity towards Jun/CRE complex. Moreover, the structural integrity of complex was affirmed through comprehensive molecular dynamics simulations, indicating a stable hydrophilic interaction between T-5224 and the Jun/CRE complex, thereby enhancing protein compactness and reducing solvent accessibility. This binding energy was further substantiated by free binding analysis, revealing a substantial thermodynamics complex state (− 448.00 ± 41.73 kJ/mol). Given that this investigation is confined to a computational framework, we additionally propose a hypothetical framework to ascertain the feasibility of inhibiting the Jun/CRE complex with T-5224 against Globoid cell leukodystrophy, employing a combination of in vitro and in vivo methodologies as a prospective avenue of this study. [ABSTRACT FROM AUTHOR]

The Hippo pathway transducers yes-associated protein (YAP) and WW-domain containing transcription regulator 1 (WWTR1/TAZ) are key regulators of liver tumorigenesis, promoting tumor formation and progression. Although the first inhibitors are in clinical trials, targeting the relevant upstream regulators of YAP/TAZ activity could prove equally beneficial. To identify regulators of YAP/TAZ activity in hepatocarcinoma (HCC) cells, we carried out a proximity labelling approach (BioID) coupled with mass spectrometry. We verified CRK-like proto-oncogene adaptor protein (CRKL) as a new YAP-exclusive interaction partner. CRKL is highly expressed in HCC patients, and its expression is associated with YAP activity as well as poor survival prognosis. In vitro experiments demonstrated CRKL-dependent cell survival and the loss of YAP binding induced through actin disruption. Moreover, we delineated the activation of the JNK/JUN pathway by CRKL, which promoted YAP transcription. Our data illustrate that CRKL not only promoted YAP activity through its binding but also through the induction of YAP transcription by JNK/JUN activation. This emphasizes the potential use of targeting the JNK/JUN pathway to suppress YAP expression in HCC patients. [ABSTRACT FROM AUTHOR]

Brachial plexus root avulsion (BPRA) injury arises from challenging delivery during childbirth, sports-related incidents, or car accidents, leading to extensive loss of motor neurons (MNs) and subsequent paralysis, including both motor and sensory impairment. Surgical nerve re-implantation cannot effectively restore motor function, and the survival of injured MNs is vital for axon regeneration and re-innervating the target muscles. Therefore, identifying novel molecular targets to improve injured MNs survival is of great significance in the treatment of BPRA injuries. Endothelin-converting enzyme-like 1 (ECEL1), a membrane-bound metallopeptidase, was initially identified as a molecule associated with nerve injuries. Damaged neurons exhibit a significant increase in the expression of ECEL1 following various types of nerve injuries, such as optic nerve injury and sciatic nerve injury. This study aimed to investigate the relationship between ECEL1 overexpression and the survival of injured MNs following BPRA injury. Our results observed a significant elevation in ECEL1 expression in injured MNs and positively correlated with MNs survival following BPRA injury. The transcription of ECEL1 is regulated by the transcription factors c-Jun and ATF3 in the context of BPRA injury, which is consistent with previous other nerve injuries study. In addition, the expression of TrkA gradually decreases in ECEL1-positive MNs and ECEL1 possibly preserves the activity of downstream AKT-GSK3β pathway of TrkA in injured MNs. In conclusion, our results introduce a promising therapeutic molecular target to assist re-implantation surgery for the treatment of BPRA injury. [ABSTRACT FROM AUTHOR]

Background and aims: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. In this study, we aimed to investigate the role and regulatory mechanism of Annexin A2 (ANXA2) in the pathogenesis of NAFLD. Methods: Histological analyses and ELISA were used to illuminate the expression of ANXA2 in NAFLD and healthy subjects. The role of ANXA2 was evaluated using high-fat diet (HFD)-fed mice via vein injection of adeno-associated viruses (AAV) knocking down ANXA2 or non-targeting control (NC) shRNAs. Moreover, HepG2 and LO2 cells were employed as in vitro hepatocyte models to investigate the expression and function of ANXA2. Results: ANXA2 was confirmed to be one of three hub genes in liver injury, and its expression was positively correlated with NAFLD activity score (NAS) and macrophage infiltration in NAFLD. Moreover, ANXA2 was significantly upregulated in NAFLD patients and HFD-fed mice. LPS/TLR4 pathway strongly upregulated ANXA2 expression, which is mediated by direct ANXA2 promoter binding by TLR4 downstream NF-κB p65 and c-Jun transcription factors. Increased ANXA2 expression was correlated with decreased autophagy flux and autophagy was activated by the depletion of ANXA2 in the models of NAFLD. Furthermore, ANXA2 interference led to the activation of AMPK/mTOR signaling axis, which may play a causal role in autophagy flux and the amelioration of steatosis. Conclusions: ANXA2 is a pathological predictor and promising therapeutic target for NAFLD. ANXA2 plays a crucial role in linking inflammation to hepatic metabolic disorder and injury, mainly through the blockage of AMPK/mTOR-mediated lipophagy. [ABSTRACT FROM AUTHOR]

Nur77 belongs to the NR4A subfamily of orphan nuclear hormone receptors. It has been shown to play important roles in metabolism, cancer progression, cellular differentiation, and the regulation of immune process. However, there has yet to be research reporting on the role of Nur77 in allergic inflammations such as anaphylaxis. This study aimed to identify molecules that could mediate allergic inflammations. To this end, we performed RNA sequencing analysis employing bone marrow-derived mast cells (BMMCs). Antigen (DNP-HSA) stimulation increased the expression levels of transcription factors such as Nr4a3 (NOR1), Nr4a1 (Nur77), and Nr4a2 (Nurr1). We focused our study on Nur77. Antigen stimulation increased the expression of Nur77 in a time- and dose-dependent manner in rat basophilic leukemia cells (RBL2H3). The downregulation of Nur77 prevented both antigen-induced increase in β-hexosaminidase activity as well as hallmarks of allergic reactions such as HDAC3, COX2, and MCP1 in RBL2H3 cells. Nur77 was necessary for both passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis (PSA). TargetScan analysis predicted that miR-21a would be a negative regulator of Nur77. miR-21a mimic negatively regulated PCA and PSA by inhibiting the hallmarks of allergic reactions. ChIP assays showed that c-JUN could bind to the promoter sequences of Nur77. Antigen stimulation increased the expression of c-JUN in RBL2H3 cells. Altogether, our findings demonstrate the regulatory role played by Nur77-miR-21a loop in allergic inflammations such as anaphylaxis, making this the first report to present the role played by Nur77 in an allergic inflammation. Our results suggest that Nur77 and miR-21 might serve as targets for developing anti-allergy drugs.

Transient receptor potential melastatin-8 (TRPM8) is a cation channel that is activated by cold and "cooling agents" such as menthol and icilin, which induce a cold sensation. The stimulation of TRPM8 activates an intracellular signaling cascade that ultimately leads to a change in the gene expression pattern of the cells. Here, we investigate the TRPM8-induced signaling pathway that links TRPM8 channel activation to gene transcription. Using a pharmacological approach, we show that the inhibition of phosphatidylinositol 4-phosphate 5 kinase α (PIP5K), an enzyme essential for the biosynthesis of phosphatidylinositol 4,5-bisphosphate, attenuates TRPM8-induced gene transcription. Analyzing the link between TRPM8 and Gq proteins, we show that the pharmacological inhibition of the βγ subunits impairs TRPM8 signaling. In addition, genetic studies show that TRPM8 requires an activated Gα subunit for signaling. In the nucleus, the TRPM8-induced signaling cascade triggers the activation of the transcription factor AP-1, a complex consisting of a dimer of basic region leucine zipper (bZIP) transcription factors. Here, we identify the bZIP protein c-Jun as an essential component of AP-1 within the TRPM8-induced signaling cascade. In summary, with PIP5K, Gq subunits, and c-Jun, we identified key molecules in TRPM8-induced signaling from the plasma membrane to the nucleus. [ABSTRACT FROM AUTHOR]

The effects of the enzyme N-acetylgalactosamine-4-sulfatase (Arylsulfatase B, ARSB), which removes the 4-sulfate group at the non-reducing end of chondroitin 4-sulfate, on the expression of PD-L1 were determined, and the underlying mechanism of PD-L1 expression was elucidated. Initial experiments in human melanoma cells (A375) showed that PD-L1 expression increased from 357 ± 31 to 796 ± 50 pg/mg protein (p < 10−11) when ARSB was silenced in A375 cells. In subcutaneous B16F10 murine melanomas, PD-L1 declined from 1227 ± 189 to 583 ± 110 pg/mg protein (p = 1.67 × 10−7), a decline of 52%, following treatment with exogenous, bioactive recombinant ARSB. This decline occurred in association with reduced tumor growth and prolongation of survival, as previously reported. The mechanism of regulation of PD-L1 expression by ARSB is attributed to ARSB-mediated alteration in chondroitin 4-sulfation, leading to changes in free galectin-3, c-Jun nuclear localization, HDAC3 expression, and effects of acetyl-H3 on the PD-L1 promoter. These findings indicate that changes in ARSB contribute to the expression of PD-L1 in melanoma and can thereby affect the immune checkpoint response. Exogenous ARSB acted on melanoma cells and normal melanocytes through the IGF2 receptor. The decline in PD-L1 expression by exogenous ARSB may contribute to the impact of ARSB on melanoma progression. [ABSTRACT FROM AUTHOR]

As an important protein encoded by hepatitis B virus (HBV), HBV X protein (HBx) plays an important role in the development of hepatocellular carcinoma (HCC). It has been shown that seven in absentia homologue 1 (SIAH1) could regulates the degradation of HBx through the ubiquitin‐proteasome pathway. However, as a member of SIAH family, the regulatory effects of SIAH2 on HBx remain unclear. In this study, we first confirmed that SIAH2 could reduce the protein levels of HBx depending on its E3 ligase activity. Moreover, SIAH2 interacted with HBx and induced its K48‐linked polyubiquitination and proteasomal degradation. Furthermore, we provided evidence that SIAH2 inhibits HBx‐associated HCC cells proliferation by regulating HBx. In conclusion, our study identified a novel role for SIAH2 in promoting HBx degradation and SIAH2 exerts an inhibitory effect in the proliferation of HBx‐associated HCC through inducing the degradation of HBx. Our study provides a new idea for the targeted degradation of HBx and may have great huge significance into providing novel evidence for the targeted therapy of HBV‐infected HCC. [ABSTRACT FROM AUTHOR]

This article explores the molecular mechanisms underlying early brain injury (EBI) following subarachnoid hemorrhage (SAH). The researchers found that inhibiting histone deacetylase 4 (HDAC4) decreased neuronal apoptosis and brain injury by suppressing the transcription of MKK7, an upstream kinase of the JNK/c-Jun pathway. The study suggests that targeting HDAC4 could be a potential strategy for preventing SAH-induced EBI. The article provides insights into the role of HDAC4 in regulating neuronal apoptosis and the JNK/c-Jun signaling pathway, offering potential therapeutic implications for neurodegenerative diseases and acute brain injuries. [Extracted from the article]

Introduction: Oral carcinogenetic is based on a variety of genomic imbalances (gross chromosome or specific gene alterations) that drive the normal oral mucosa to its neoplastic/dysplastic epithelial form and finally to a totally malignant tissue transformation. In this multi-step procedure, down-regulation of suppressor genes combined with overactivation of oncogenes are two crucial and partially early genetic events involved in the onset and progression of neoplastic/malignant epithelia transformation. More specifically, deregulation of strong transcription factors negatively affects the normal expression of a broad spectrum of genes that are involved in cell proliferation and signalling transduction to the nucleus. Objective: The purpose of the current molecular review was to explore the c-Jun (chromosome location: 1p32-p31) transcription factor transformation mechanisms to oncogene in oral squamous cell carcinoma (OSCC). Material and method: A systematic review of the literature was carried out by searching in PubMed international database. The year 2010 was set as a prominent time limit for the publication date of the articles in the majority of them, whereas specific references of great importance and historical value in the field of the c-Jun gene discovery and analysis were also included. The following keywords were used: c-Jun, oncogene, signaling pathway, oral, carcinoma, transcription. A pool of 45 important articles were selected for the present study at the basis of combining molecular knowledge with new targeted therapeutic strategies. Results: C-Jun -- as a part of the c-Jun/c-Fos transcription factors' complex --critically regulates the expression levels in a variety of genes inside the cellular microenvironment. A broad spectrum of malignancies, including OSCC, demonstrate c-Jun alterations driving the gene to its oncogenic phenotype. Interestingly, c-Jun oncogenic activation is mediated by high-risk human papilloma virus (HR-HPV) persistent infection in significant subsets of these malignancies. Conclusions: C-Jun was the first oncogene -- acting as a strong transcription factor -- that was discovered and cloned 35 years ago. C-Jun is the living history of oncogenes and its discovery marks a significant step in the evolution of molecular biology. [ABSTRACT FROM AUTHOR]

Diffuse large B-cell lymphoma (DLBCL) stands out as the most common type of malignant cancer, representing the majority of cases of non-Hodgkin's lymphoma. Ethyl pyruvate (EP) is a derivative of pyruvic acid and found to have potent anti-tumor properties. Despite its potential benefits, the impact of EP on DLBCL remains ambiguous. Our objective is to elucidate the role of EP in modulating the development of DLBCL. Analysis of cholecystokinin-8 (CCK-8) revealed that treatment with EP significantly diminished the viability of DLBCL cells. Furthermore, EP administration suppressed colony formation and hindered cell adhesion and invasion in DLBCL cells. Examination of cell cycle progression showed that EP treatment induced arrest at the G1 phase and subsequently reduced the S phase population in DLBCL cells. EP treatment consistently exhibited apoptosis-inducing properties in Annexin-V assays, and notably downregulated the expression of Bcl-2 while increasing levels of proapoptotic cleaved caspase 3 and BAX in DLBCL cells. Additionally, EP treatment decreased the overexpression of c-Jun in c-Jun-transfected DLBCL cells. Further, EP demonstrated DNA-damaging effects in TUNEL assays. In vivo, xenograft animal models revealed that EP treatment significantly mitigated DLBCL tumor growth and suppressed DLBCL cell adhesion to bone marrow stromal cells. In summary, these findings suggest that EP mitigates DLBCL progression by inducing apoptosis, inducing cell cycle arrest, and promoting DNA damage. [ABSTRACT FROM AUTHOR]

Background: Cholangiocarcinoma (CCA) is the second most common primary malignancy of the liver and is associated with poor prognosis. Despite the emerging role of glycine amidinotransferase (GATM) in cancer development, its function in CCA remains elusive. This study investigated the biological significance and molecular mechanisms of GATM in CCA. Method: GATM expression was measured using immunohistochemistry and western blotting. Cell proliferation, migration, and invasion were assessed through CCK-8, EdU, clone formation, wound healing, and Transwell assays. Rescue experiments were performed to determine whether the JNK/c-Jun pathway is involved in GATM-mediated CCA development. Immunoprecipitation and mass spectrometry were performed to screen for proteins that interact with GATM. The role of GATM in vivo was investigated according to the xenograft experiment. Result: GATM expression was downregulated in CCA tissues and cells (p

Abstract Background Bladder cancer is the second most common genitourinary malignancy worldwide. The death rate of bladder cancer has increased every year. However, the molecular mechanism of bladder cancer is not sufficiently studied. Deubiquitinating enzymes (DUBs) play an important role in carcinogenesis. Several studies have demonstrated that USP5 associated with malignancy and pathological progression in hepatocellular carcinoma, colorectal and non-small cell lung cancer. However, the role of USP5 in bladder cancer need to be explored. Methods The USP5 expression was analysed using the web server GEPIA. To explore USP5 function in bladder cancer, we constructed USP5-knockout cell lines in T24 cells. A FLAG-USP5 (WT USP5) plasmid and a plasmid FLAG-USP5 C335A (catalytic-inactive mutant) used to overexpress USP5 in EJ cells. CCK8, colony formation, transwell and scratch assays were used to assess cell viability, proliferation and migration. RNA sequencing (RNA-seq) and dual-luciferase reporter assays were performed to screen the pathway. Coimmunoprecipitation and immunofluorescence were used to explore the interaction between USP5 and c-Jun. Cycloheximide (CHX) chase assays were performed to establish the effect of USP5 on c-Jun stability. Xenograft mouse model was used to study the role of USP5 in bladder cancer. Results USP5 expression is increased in bladder cancer patients. Genetic ablation of USP5 markedly inhibited bladder cancer cell proliferation, viability, and migration both in vitro and in vivo. RNA-seq and luciferase pathway screening showed that USP5 activated JNK signalling, and we identified the interaction between USP5 and c-Jun. USP5 was found to activate c-Jun by inhibiting its ubiquitination. Conclusions Our results show that high USP5 expression promotes bladder cancer progression by stabilizing c-Jun and that USP5 is a potential therapeutic target in bladder cancer.

Background: Schwann cells (SCs) and their plasticity contribute to the peripheral nervous system’s capacity for nerve regeneration after injury. The Egr2/Krox20 promoter antisense RNA (Egr2-AS) recruits chromatin remodeling complexes to inhibit Egr2 transcription following peripheral nerve injury. Methods: RNA-seq and ATAC-seq were performed on control cells, Lenti-GFP-transduced cells, and cells overexpressing Egr2-AS (Lenti-AS). Egr2 AS-RNA was cloned into the pLVX-DsRed-Express2-N1 lentiviral expression vector (Clontech, Mountain View, CA, USA), and the levels of AS-RNA expression were determined. Ezh2 and Wdr5 were immunoprecipitated from rat SCs and RT-qPCR was performed against AS-Egr2 RNA. ChIP followed by DNA purification columns was used to perform qPCR for relevant promoters. Hi-C, HiC-DC+, R, Bioconductor, and TOBIAS were used for significant and differential loop analysis, identifications of COREs and CORE-promotor loops, comparisons of TF activity at promoter sites, and identification of site-specific TF footprints. OnTAD was used to detect TADs, and Juicer was used to identify A/B compartments. Results: Here we show that a Neuregulin-ErbB2/3 signaling axis mediates binding of the Egr2-AS to YY1Ser184 and regulates its expression. Egr2-AS modulates the chromatin accessibility of Schwann cells and interacts with two distinct histone modification complexes. It binds to EZH2 and WDR5 and enables targeting of H3K27me3 and H3K4me3 to promoters of Egr2 and C-JUN, respectively. Expression of the Egr2-AS results in reorganization of the global chromatin landscape and quantitative changes in the loop formation and contact frequency at domain boundaries exhibiting enrichment for AP-1 genes. In addition, the Egr2-AS induces changes in the hierarchical TADs and increases transcription factor binding scores on an inter-TAD loop between a super-enhancer regulatory hub and the promoter of mTOR. Conclusions: Our results show that Neuregulin-ErbB2/3-YY1 regulates the expression of Egr2-AS, which mediates remodeling of the chromatin landscape in Schwann cells.

Cancer-induced bone pain (CIBP) is one of the most common and feared symptoms in patients with advanced tumors. The X-C motif chemokine ligand 12 (CXCL12) and the CXCR4 receptor have been associated with glial cell activation in bone cancer pain. Moreover, mitogen-activated protein kinases (MAPKs), as downstream CXCL12/CXCR4 signals, and c-Jun, as activator protein AP-1 components, contribute to the development of various types of pain. However, the specific CIBP mechanisms remain unknown. Esketamine is a non-selective N-methyl- d -aspartic acid receptor (NMDA) inhibitor commonly used as an analgesic in the clinic, but its analgesic mechanism in bone cancer pain remains unclear. We used a tumor cell implantation (TCI) model and explored that CXCL12/CXCR4, p-MAPKs, and p-c-Jun were stably up-regulated in the spinal cord. Immunofluorescence images showed activated microglia in the spinal cord on day 14 after TCI and co-expression of CXCL12/CXCR4, p-MAPKs (p-JNK, p-ERK, p-p38 MAPK), and p-c-Jun in microglia. Intrathecal injection of the CXCR4 inhibitor AMD3100 reduced JNK and c-Jun phosphorylations, and intrathecal injection of the JNK inhibitor SP600125 and esketamine also alleviated TCI-induced pain and reduced the expression of p-JNK and p-c-Jun in microglia. Overall, our data suggest that the CXCL12/CXCR4-JNK-c-Jun signaling pathway of microglia in the spinal cord mediates neuronal sensitization and pain hypersensitivity in cancer-induced bone pain and that esketamine exerts its analgesic effect by inhibiting the JNK-c-Jun pathway. [ABSTRACT FROM AUTHOR]

Breast cancer can perform metastasis to distant organs and cause more than 90% of malignancy-related deaths. The anti-metastasis potency of nanodiamondconjugated annonacin and squamocin against MCF-7 cells is currently studied. First, IC50 determination of both free annonacin and squamocin to evaluate their potency as cytotoxic agents. Upon getting the IC50 value, both compounds are conjugated into nanodiamonds. Drug loading efficiencies of nanodiamondconjugated annonacin and squamocin are 88.9% and 89.1%, respectively. Meanwhile, the ND-annonacin and ND-squamocin complex size is 150-300 nm based on SEM imaging. Subsequently, cell viability assessment of MCF-7 was performed with six cohort designs, namely, K (control cell), AN (annonacin), SQ (squamocin), NDAN (nanodiamond-conjugated annonacin), and NDSQ (nanodiamond-conjugated squamocin). Both IC50 and cell viability are assessed by MTT assay after 24 h incubation. All cohorts also underwent gene expression analysis subject to the metastasis markers CTNND1 (catenin delta 1), NOTCH4, and C-JUN. Here, the IC50 of both free annonacin (4.52 µg/ml) and squamocin (10.03 µg/ml) are more than IC50 of potent anticancer (< 4 µg/ml) for pure compounds. However, nanodiamond conjugation to both compounds can decrease cell viability better than free compounds. Compared to K, nanodiamond-conjugated annonacin and squamocin significantly decreases cell viability after 24 h incubation. Bioinformatics analysis confirmed significant prometastasis (C-JUN and NOTCH4) upregulation and anti-metastasis (CTNND1) downregulation in tumors compared to normal. Recent findings demonstrated that nanodiamond-conjugated annonacin can significantly upregulate CTNND1 and significantly downregulate C-JUN and NOTCH4. Even so, nanodiamondconjugated squamocin upregulate CTNND1 but not significantly and significantly downregulate C-JUN and NOTCH4. [ABSTRACT FROM AUTHOR]

Herpes simplex virus-1 (HSV-1) establishes a latent infection in peripheral neurons and periodically reactivates to permit transmission, which can result in clinical manifestations. Viral transactivators required for lytic infection are largely absent during latent infection, and therefore, HSV-1 relies on the co-option of neuronal host signaling pathways to initiate its gene expression. The activation of the neuronal c-Jun N-terminal kinase (JNK) cell stress pathway is central to initiating biphasic reactivation in response to multiple stimuli. However, how host factors work with JNK to stimulate the initial wave of gene expression (known as Phase I) or the progression to full Phase II reactivation remains unclear. Here, we found that c-Jun, the primary target downstream of neuronal JNK cell stress signaling, functions during reactivation but not during the JNK-mediated initiation of Phase I gene expression. Instead, c-Jun was required to transition from Phase I to full HSV-1 reactivation and was detected in viral replication compartments of reactivating neurons. Interestingly, we also identified a role for both c-Jun and enhanced neuronal stress during initial neuronal infection in promoting a more reactivation-competent form of HSV-1 latency. Therefore, c-Jun functions at multiple stages during the HSV latent infection of neurons to promote reactivation but not during the initial JNK-dependent Phase I. Importantly, by demonstrating that initial infection conditions can contribute to later reactivation abilities, this study highlights the potential for latently infected neurons to maintain a molecular scar of previous exposure to neuronal stressors. IMPORTANCE The molecular mechanisms that regulate the reactivation of herpes simplex virus-1 (HSV-1) from latent infection are unknown. The host transcription and pioneer factor c-Jun is the main target of the JNK cell stress pathway that is known to be important in exit of HSV from latency. Surprisingly, we found that c-Jun does not act with JNK during exit from latency but instead promotes the transition to full reactivation. Moreover, c-Jun and enhanced neuronal stress during initial neuronal infection promoted a more reactivation-competent form of HSV-1 latency. c-Jun, therefore, functions at multiple stages during HSV-1 latent infection of neurons to promote reactivation. Importantly, this study contributes to a growing body of evidence that de novo HSV-1 infection conditions can modulate latent infection and impact future reactivation events, raising important questions on the clinical impact of stress during initial HSV-1 acquisition on future reactivation events and consequences. [ABSTRACT FROM AUTHOR]

Oleanolic acid (OA) is a natural triterpenoid with therapeutic potential for a multitude of diseases. However, the precise mechanism by which OA influences stress‐induced apoptosis of intestinal epithelial cells remains elusive. Therefore, the effect of OA on intestinal diseases under stressful conditions and its possible mechanisms have been investigated. In a hydrogen peroxide (H2O2)‐induced oxidative stress model, OA attenuated H2O2‐induced apoptosis in a concentration‐dependent manner. To investigate the underlying mechanisms, the gene expression profile of OA on IPEC‐J2 cells was analyzed using an RNA sequencing system. Results from gene ontology and Kyoto encyclopedia of genes and genomes analysis confirmed that OA may mitigate the cytotoxic effects of H2O2 by downregulating gene expression through the MAPK signaling pathway. Furthermore, Quantitative real‐time polymerase chain reaction results validated the differentially expressed genes data. Western blot analysis further demonstrated that OA effectively suppressed the expression level of c‐Jun protein induced by H2O2 in IPEC‐J2 cells. Collectively, our results indicate that OA pretreatment significantly attenuated H2O2‐induced apoptosis in intestinal epithelial cells through suppressing c‐Jun and MAPK pathway. [ABSTRACT FROM AUTHOR]

Abstract Background Morbidity and mortality associated with cardiovascular diseases, such as myocardial infarction, stem from the inability of terminally differentiated cardiomyocytes to regenerate, and thus repair the damaged myocardial tissue structure. The molecular biological mechanisms behind the lack of regenerative capacity for those cardiomyocytes remains to be fully elucidated. Recent studies have shown that c-Jun serves as a cell cycle regulator for somatic cell fates, playing a key role in multiple molecular pathways, including the inhibition of cellular reprogramming, promoting angiogenesis, and aggravation of cardiac hypertrophy, but its role in cardiac development is largely unknown. This study aims to delineate the role of c-Jun in promoting early-stage cardiac differentiation. Methods The c-Jun gene in mouse embryonic stem cells (mESCs) was knocked out with CRISPR-Cas9, and the hanging drop method used to prepare the resulting embryoid bodies. Cardiac differentiation was evaluated up to 9 days after c-Jun knockout (ko) via immunofluorescence, flow cytometric, and qPCR analyses. Results Compared to the wild-type control group, obvious beating was observed among the c-Jun-ko mESCs after 6 days, which was also associated with significant increases in myocardial marker expression. Additionally, markers associated with mesoderm and endoderm cell layer development, essential for further differentiation of ESCs into cardiomyocytes, were also up-regulated in the c-Jun-ko cell group. Conclusions Knocking out c-Jun directs ESCs toward a meso-endodermal cell lineage fate, in turn leading to generation of beating myocardial cells. Thus, c-Jun plays an important role in regulating early cardiac cell development.

Abstract Background Ankyrin repeat domain 49 (ANKRD49) has been found to be highly expressed in multiple cancer including lung adenocarcinoma (LUAD) and lung squamous carcinoma (LUSC). However, the function of ANKRD49 in the pathogenesis of NSCLC still remains elusive. Previously, ANKRD49 has been demonstrated to promote the invasion and metastasis of A549 cells, a LUAD cell line, via activating the p38-ATF-2-MMP2/MMP9 pathways. Considering the heterogeneity of tumor cells, the function and mechanism of ANKRD49 in NSCLC need more NSCLC-originated cells to clarify. Methods Real-time qPCR was employed to test ANKRD49 expression levels in nine pairs of fresh NSCLC tissues and the corresponding adjacent normal tissues. The function of ANKRD49 was investigated using overexpression and RNA interference assays in lung adenocarcinoma cell line (NCI-H1299) and lung squamous carcinoma cell line (NCI-H1703) through gelatin zymography, cell counting kit-8, colony formation, wound healing, migration and invasion assays mmunoprecipitation was performed to in vitro. Immunoprecipitation was performed to test the interaction of c-Jun and ATF2. Chromatin immunoprecipitation was conducted to assess the transcriptional regulation of ATF2/c-Jun on MMP-2/9. Moreover, the tumorigenicity of ANKRD49 was evaluated in nude mice models and the involved signal molecular was also measured by immunohistochemical method. Results We found that the levels of ANKRD49 in cancerous tissues were higher than those in adjacent normal tissues. in vitro assay showed that ANKRD49 promoted the migration and invasion of NCI-H1299 and NCI-H1703 cells via enhancing the levels of MMP-2 and MMP-9. Furthermore, ANKRD49 elevated phosphorylation of JNK and then activated c-Jun and ATF2 which interact in nucleus to promote the binding of ATF2:c-Jun with the promoter MMP-2 or MMP-9. In vivo assay showed that ANKRD49 promoted lung metastasis of injected-NSCLC cells and the high metastatic rate was positively correlated with the high expression of ANKRD49, MMP-2, MMP-9, p-JNK, p-c-Jun and p-ATF2. Conclusion The present study indicated that ANKRD49 accelerated the invasion and metastasis of NSCLC cells via JNK-mediated transcription activation of c-Jun and ATF2 which regulated the expression of MMP-2/MMP-9. The molecular mechanisms of ANKRD49’s function is different from those found in A549 cells. The current study is a supplement and improvement to the previous research.

Abstract Background Maintaining the repair phenotype of denervated Schwann cells in the injured distal nerve is crucial for promoting peripheral nerve regeneration. However, when chronically denervated, the capacity of Schwann cells to support repair and regeneration deteriorates, leading to peripheral nerve regeneration and poor functional recovery. Herein, we investigated whether neurotrophin-3 (NT-3) could sustain the reparative phenotype of Schwann cells and promote peripheral nerve regeneration after chronic denervation and aimed to uncover its potential molecular mechanisms. Methods Western blot was employed to investigate the relationship between the expression of c-Jun and the reparative phenotype of Schwann cells. The inducible expression of c-Jun by NT-3 was examined both in vitro and in vivo with western blot and immunofluorescence staining. A chronic denervation model was established to study the role of NT-3 in peripheral nerve regeneration. The number of regenerated distal axons, myelination of regenerated axons, reinnervation of neuromuscular junctions, and muscle fiber diameters of target muscles were used to evaluate peripheral nerve regeneration by immunofluorescence staining, transmission electron microscopy (TEM), and hematoxylin and eosin (H&E) staining. Adeno-associated virus (AAV) 2/9 carrying shRNA, small molecule inhibitors, and siRNA were employed to investigate whether NT-3 could signal through the TrkC/ERK pathway to maintain c-Jun expression and promote peripheral nerve regeneration after chronic denervation. Results After peripheral nerve injury, c-Jun expression progressively increased until week 5 and then began to decrease in the distal nerve following denervation. NT-3 upregulated the expression of c-Jun in denervated Schwann cells, both in vitro and in vivo. NT-3 promoted peripheral nerve regeneration after chronic denervation, mainly by upregulating or maintaining a high level of c-Jun rather than NT-3 itself. The TrkC receptor was consistently presented on denervated Schwann cells and served as NT-3 receptors following chronic denervation. NT-3 mainly upregulated c-Jun through the TrkC/ERK pathway. Conclusion NT-3 promotes peripheral nerve regeneration by maintaining the repair phenotype of Schwann cells after chronic denervation via the TrkC/ERK/c-Jun pathway. It provides a potential target for the clinical treatment of peripheral nerve injury after chronic denervation.

Abstract Background c-Jun is a proto-oncogene functioning as a transcription factor to activate gene expression under many physiological and pathological conditions, particularly in somatic cells. However, its role in early embryonic development remains unknown. Results Here, we show that c-Jun acts as a one-way valve to preserve the primed state and impair reversion to the naïve state. c-Jun is induced during the naive to primed transition, and it works to stabilize the chromatin structure and inhibit the reverse transition. Loss of c-Jun has surprisingly little effect on the naïve to primed transition, and no phenotypic effect on primed cells, however, in primed cells the loss of c-Jun leads to a failure to correctly close naïve-specific enhancers. When the primed cells are induced to reprogram to a naïve state, these enhancers are more rapidly activated when c-Jun is lost or impaired, and the conversion is more efficient. Conclusions The results of this study indicate that c-Jun can function as a chromatin stabilizer in primed EpiSCs, to maintain the epigenetic cell type state and act as a one-way valve for cell fate conversions.

Filaggrin (FLG) is an essential structural protein expressed in differentiated keratinocytes. Insufficient FLG expression contributes to the pathogenesis of chronic inflammatory skin diseases. Saikosaponin A (SSA), a bioactive oleanane-type triterpenoid, exerts anti-inflammatory activity. However, the effects of topically applied SSA on FLG expression in inflamed skin remain unclear. This study aimed to evaluate the biological activity of SSA in restoring reduced FLG expression. The effect of SSA on FLG expression in HaCaT cells was assessed through various biological methods, including reverse transcription PCR, quantitative real-time PCR, immunoblotting, and immunofluorescence staining. TNFα and IFNγ decreased FLG mRNA, cytoplasmic FLG protein levels, and FLG gene promoter–reporter activity compared to the control groups. However, the presence of SSA restored these effects. A series of FLG promoter–reporter constructs were generated to investigate the underlying mechanism of the effect of SSA on FLG expression. Mutation of the AP1-binding site (mtAP1) in the −343/+25 FLG promoter–reporter abrogated the decrease in reporter activities caused by TNFα + IFNγ, suggesting the importance of the AP1-binding site in reducing FLG expression. The SSA treatment restored FLG expression by inhibiting the expression and nuclear localization of FRA1 and c-Jun, components of AP1, triggered by TNFα + IFNγ stimulation. The ERK1/2 mitogen-activated protein kinase signaling pathway upregulates FRA1 and c-Jun expression, thereby reducing FLG levels. The SSA treatment inhibited ERK1/2 activation caused by TNFα + IFNγ stimulation and reduced the levels of FRA1 and c-Jun proteins in the nucleus, leading to a decrease in the binding of FRA1, c-Jun, p-STAT1, and HDAC1 to the AP1-binding site in the FLG promoter. The effect of SSA was evaluated in an animal study using a BALB/c mouse model, which induces human atopic-dermatitis-like skin lesions via the topical application of dinitrochlorobenzene. Topically applied SSA significantly reduced skin thickening, immune cell infiltration, and the expression of FRA1, c-Jun, and p-ERK1/2 compared to the vehicle-treated group. These results suggest that SSA can effectively recover impaired FLG levels in inflamed skin by preventing the formation of the repressor complex consisting of FRA1, c-Jun, HDAC1, and STAT1.

Aims: Heme oxygenase (HO-1) affords protection against ischaemia/reperfusion (I/R) injury; however, its effects on testicular I/R injury remain poorly explored. Herein, we aimed to examine the effects of HO-1 on testicular I/R injury and elucidate the underlying mechanism. Methods: Using the TALEN technique, we knocked out the HO-1 gene from rats. In vivo: Thirty hmox+/+ and 30 hmox−/− rats were randomly assigned to six groups: sham-operated (sham), I/R (the left testicle torsion/detorsion) 0 d,I/R 1d, I/R 3d, I/R 7d and I/R 28d. In vitro: GC-1 were suffered from: control,H/R (oxygen-deprivation/reoxygenation),H/R + HO-1 siRNA,H/R + c-Jun siRNA or H/R + HO-1 siRNA + c-jun.We performed immunofluorescence and immunohistochemistry experiments to detect HO-1 nuclear translocation. Flow cytometry was used to detect cell apoptosis and analyse the cell cycle. High-resolution miRNA, mRNA sequencing, reverse transcription-quantitative PCR, and western blotting were performed to identify testicular I/R injury-related genes strongly conserved in HO-1 knockout rats. A double luciferase reporter assay was performed to verify the relationship between C-jun and miR-221/222. Main findings: In vivo, HO-1 improved the pathological damage induced by testicular I/R. In GC-1 cells, we confirmed the nuclear translocation of HO-1 and its protective effect against hypoxia/reoxygenation (H/R) damage. Accordingly, HO-1 protein itself, rather than heme metabolites, might play a key role in testicular I/R. Gene sequencing was performed to screen for miR221/222 and its downstream gene, thymocyte selection-associated high mobility group box (TOX). HO-1 increased c-Jun phosphorylation in the H/R group, knocked down c-Jun in GC-1 cells, and decreased miR-221/222 expression. Inhibition of HO-1 expression decreased the expression of c-Jun and miR-221/222, which was rescued by adding c-Jun. Dual-luciferase reporter assay confirmed the interaction between c-Jun and miR-221/222. Conclusions: HO-1 could exert a protective effect against testicular I/R via the phosphorylated c-Jun-miR-221/222-TOX pathway.

Background: Morbidity and mortality associated with cardiovascular diseases, such as myocardial infarction, stem from the inability of terminally differentiated cardiomyocytes to regenerate, and thus repair the damaged myocardial tissue structure. The molecular biological mechanisms behind the lack of regenerative capacity for those cardiomyocytes remains to be fully elucidated. Recent studies have shown that c-Jun serves as a cell cycle regulator for somatic cell fates, playing a key role in multiple molecular pathways, including the inhibition of cellular reprogramming, promoting angiogenesis, and aggravation of cardiac hypertrophy, but its role in cardiac development is largely unknown. This study aims to delineate the role of c-Jun in promoting early-stage cardiac differentiation. Methods: The c-Jun gene in mouse embryonic stem cells (mESCs) was knocked out with CRISPR-Cas9, and the hanging drop method used to prepare the resulting embryoid bodies. Cardiac differentiation was evaluated up to 9 days after c-Jun knockout (ko) via immunofluorescence, flow cytometric, and qPCR analyses. Results: Compared to the wild-type control group, obvious beating was observed among the c-Jun-ko mESCs after 6 days, which was also associated with significant increases in myocardial marker expression. Additionally, markers associated with mesoderm and endoderm cell layer development, essential for further differentiation of ESCs into cardiomyocytes, were also up-regulated in the c-Jun-ko cell group. Conclusions: Knocking out c-Jun directs ESCs toward a meso-endodermal cell lineage fate, in turn leading to generation of beating myocardial cells. Thus, c-Jun plays an important role in regulating early cardiac cell development. [ABSTRACT FROM AUTHOR]

Simple Summary: N7-methylguanosine (m7G) methylation plays an important role in the development of pancreatic adenocarcinoma (PDAC). Among the 29 regulatory genes of m7G methylation, they can be roughly divided into three categories: methyltransferase (writer), demethylase (eraser), and binding protein (reader) according to their functions. In this study, we explore the role of m7G reader NCBP2 in PDAC progression: NCBP2 activates MEK/ERK signaling by upregulating c-JUN, thereby promoting PDAC cell proliferation. In summary, we identify a novel potential therapeutic target for PDAC, which sheds new light on the treatment of PDAC patients. PDAC is one of the most common malignant tumors worldwide. The difficulty of early diagnosis and lack of effective treatment are the main reasons for its poor prognosis. Therefore, it is urgent to identify novel diagnostic and therapeutic targets for PDAC patients. The m7G methylation is a common type of RNA modification that plays a pivotal role in regulating tumor development. However, the correlation between m7G regulatory genes and PDAC progression remains unclear. By integrating gene expression and related clinical information of PDAC patients from TCGA and GEO cohorts, m7G binding protein NCBP2 was found to be highly expressed in PDAC patients. More importantly, PDAC patients with high NCBP2 expression had a worse prognosis. Stable NCBP2-knockdown and overexpression PDAC cell lines were constructed to further perform in-vitro and in-vivo experiments. NCBP2-knockdown significantly inhibited PDAC cell proliferation, while overexpression of NCBP2 dramatically promoted PDAC cell growth. Mechanistically, NCBP2 enhanced the translation of c-JUN, which in turn activated MEK/ERK signaling to promote PDAC progression. In conclusion, our study reveals that m7G reader NCBP2 promotes PDAC progression by activating MEK/ERK pathway, which could serve as a novel therapeutic target for PDAC patients. [ABSTRACT FROM AUTHOR]

Background: Ankyrin repeat domain 49 (ANKRD49) has been found to be highly expressed in multiple cancer including lung adenocarcinoma (LUAD) and lung squamous carcinoma (LUSC). However, the function of ANKRD49 in the pathogenesis of NSCLC still remains elusive. Previously, ANKRD49 has been demonstrated to promote the invasion and metastasis of A549 cells, a LUAD cell line, via activating the p38-ATF-2-MMP2/MMP9 pathways. Considering the heterogeneity of tumor cells, the function and mechanism of ANKRD49 in NSCLC need more NSCLC-originated cells to clarify. Methods: Real-time qPCR was employed to test ANKRD49 expression levels in nine pairs of fresh NSCLC tissues and the corresponding adjacent normal tissues. The function of ANKRD49 was investigated using overexpression and RNA interference assays in lung adenocarcinoma cell line (NCI-H1299) and lung squamous carcinoma cell line (NCI-H1703) through gelatin zymography, cell counting kit-8, colony formation, wound healing, migration and invasion assays mmunoprecipitation was performed to in vitro. Immunoprecipitation was performed to test the interaction of c-Jun and ATF2. Chromatin immunoprecipitation was conducted to assess the transcriptional regulation of ATF2/c-Jun on MMP-2/9. Moreover, the tumorigenicity of ANKRD49 was evaluated in nude mice models and the involved signal molecular was also measured by immunohistochemical method. Results: We found that the levels of ANKRD49 in cancerous tissues were higher than those in adjacent normal tissues. in vitro assay showed that ANKRD49 promoted the migration and invasion of NCI-H1299 and NCI-H1703 cells via enhancing the levels of MMP-2 and MMP-9. Furthermore, ANKRD49 elevated phosphorylation of JNK and then activated c-Jun and ATF2 which interact in nucleus to promote the binding of ATF2:c-Jun with the promoter MMP-2 or MMP-9. In vivo assay showed that ANKRD49 promoted lung metastasis of injected-NSCLC cells and the high metastatic rate was positively correlated with the high expression of ANKRD49, MMP-2, MMP-9, p-JNK, p-c-Jun and p-ATF2. Conclusion: The present study indicated that ANKRD49 accelerated the invasion and metastasis of NSCLC cells via JNK-mediated transcription activation of c-Jun and ATF2 which regulated the expression of MMP-2/MMP-9. The molecular mechanisms of ANKRD49's function is different from those found in A549 cells. The current study is a supplement and improvement to the previous research. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is one of the most common human malignancies due to its invasiveness and metastasis. Recent studies revealed the pivotal roles of long noncoding RNAs (lncRNAs) in tumorigenesis and progressions of various tumors. However, the biological roles and molecular mechanisms of long intergenic noncoding RNA 00174 (LINC00174) in human CRC remain unclear. Here, we report that LINC00174 expression was higher in human CRC tissues and cell lines than in adjacent normal tissues and a colon epithelial cell line (FHC). High expression of LINC00174 was positively correlated with poor overall and disease‐free survival in patients with CRC. Loss‐ and gain‐of‐function of LINC00174 demonstrated its critical roles in promoting cell proliferation, apoptosis resistance, migration, and invasion of CRC cells in vitro. Moreover, overexpression of LINC00174 enhanced tumor growth in vivo. Mechanistic experiments revealed that LINC00174 could bind to microRNA (miR)−2467‐3p and augment the expression and function of ubiquitin‐specific peptidase 21 (USP21). Rescue assays found that miR‐2467‐3p inhibition can offset the actions of LINC00174 or USP21 knockdown in CRC cells. Additionally, transcriptional factor c‐JUN transcriptionally activated LINC00174 expression and mediated LINC00174‐induced malignant phenotypes of CRC cell lines. Totally, our findings shed light on a new therapeutic strategy in modulating LINC00174/miR‐2467‐3p, which may interfere with the expression of USP21, and revealed that LINC00174 could be a new therapeutic target or prognostic marker in CRC. [ABSTRACT FROM AUTHOR]

Background: c-Jun is a proto-oncogene functioning as a transcription factor to activate gene expression under many physiological and pathological conditions, particularly in somatic cells. However, its role in early embryonic development remains unknown. Results: Here, we show that c-Jun acts as a one-way valve to preserve the primed state and impair reversion to the naïve state. c-Jun is induced during the naive to primed transition, and it works to stabilize the chromatin structure and inhibit the reverse transition. Loss of c-Jun has surprisingly little effect on the naïve to primed transition, and no phenotypic effect on primed cells, however, in primed cells the loss of c-Jun leads to a failure to correctly close naïve-specific enhancers. When the primed cells are induced to reprogram to a naïve state, these enhancers are more rapidly activated when c-Jun is lost or impaired, and the conversion is more efficient. Conclusions: The results of this study indicate that c-Jun can function as a chromatin stabilizer in primed EpiSCs, to maintain the epigenetic cell type state and act as a one-way valve for cell fate conversions. [ABSTRACT FROM AUTHOR]

Wound healing is a complex process to restore skin. Plant-derived bioactive compounds might be a source of substances for the treatment of wounds stalled in a non-resolving stage of wound healing. Oleanolic acid (OA), a pentacyclic triterpene, has shown favorable wound healing properties both in vitro and in vivo. Unfortunately, OA cannot be solubilized in aqueous media, and it needs to be helped by the use of dimethyl sulfoxide (DMSO). In this paper, we have shown that cyclodextrins (CDs) are a good alternative to DMSO as agents to deliver OA to cells, providing better features than DMSO. Cyclodextrins are natural macromolecules that show a unique tridimensional structure that can encapsulate a wide variety of hydrophobic compounds. We have studied the cyclodextrin-encapsulated form of OA with OA/DMSO, comparing their stability, biological properties for cell migration, and cell viability. In addition, detailed parameters related to cell migration and cytoskeletal reorganization have been measured and compared. Our results show that OA-encapsulateds compound exhibit several advantages when compared to non-encapsulated OA in terms of chemical stability, migration enhancement, and preservation of cell viability. [ABSTRACT FROM AUTHOR]

Abstract Background Articular injection of mesenchymal stem cells (MSCs) has been applied to treat knee osteoarthritis (kOA), but its clinical outcomes are controversial. This study investigated whether an articular inflammatory microenvironment (AIM) impacts MSC-based therapy in a rat model of kOA. Methods The biological change of MSCs and the functional change of MSCs on chondrocytes were evaluated under AIM. The key mediator and mechanism for the AIM impact on MSC therapy were explored via gain- and loss-of-function approaches. Results The results showed that MSCs exerted potent anti-kOA effects in vivo and in vitro, but that this therapy become chondrodestructive if a chronic AIM was present. Mechanistically, the overexpression of MMP13 in the injected MSCs via a MAPKs-AP1 signaling axis was revealed as the underlying mechanism for the detriment outcome. Conclusions This study thus clarifies recent clinical findings while also suggesting a means to overcome any detrimental effects of MSC-based therapy while improving its efficacy.

Abstract Background Globally, despite prostate cancer (PCa) representing second most prevalent malignancy in male, the precise molecular mechanisms implicated in its pathogenesis remain unclear. Consequently, elucidating the key molecular regulators that govern disease progression could substantially contribute to the establishment of novel therapeutic strategies, ultimately advancing the management of PCa. Methods A total of 49 PCa tissues and 43 adjacent normal tissues were collected from January 2017 to December 2021 at Zhongnan Hospital of Wuhan University. The advanced transcriptomic methodologies were employed to identify differentially expressed mRNAs in PCa. The expression of aspartoacylase (ASPA) in PCa was thoroughly evaluated using quantitative real-time PCR and Western blotting techniques. To elucidate the inhibitory role of ASPA in PCa cell proliferation and metastasis, a comprehensive set of in vitro and in vivo assays were conducted, including orthotopic and tumor-bearing mouse models (n = 8 for each group). A combination of experimental approaches, such as Western blotting, luciferase assays, immunoprecipitation assays, mass spectrometry, glutathione S-transferase pull-down experiments, and rescue studies, were employed to investigate the underlying molecular mechanisms of ASPA’s action in PCa. The Student’s t-test was employed to assess the statistical significance between two distinct groups, while one-way analysis of variance was utilized for comparisons involving more than two groups. A two-sided P value of less than 0.05 was deemed to indicate statistical significance. Results ASPA was identified as a novel inhibitor of PCa progression. The expression of ASPA was found to be significantly down-regulated in PCa tissue samples, and its decreased expression was independently associated with patients’ prognosis (HR = 0.60, 95% CI 0.40–0.92, P = 0.018). Our experiments demonstrated that modulation of ASPA activity, either through gain- or loss-of-function, led to the suppression or enhancement of PCa cell proliferation, migration, and invasion, respectively. The inhibitory role of ASPA in PCa was further confirmed using orthotopic and tumor-bearing mouse models. Mechanistically, ASPA was shown to directly interact with the LYN and inhibit the phosphorylation of LYN as well as its downstream targets, JNK1/2 and C-Jun, in both PCa cells and mouse models, in an enzyme-independent manner. Importantly, the inhibition of LYN activation by bafetinib abrogated the promoting effect of ASPA knockdown on PCa progression in both in vitro and in vivo models. Moreover, we observed an inverse relationship between ASPA expression and LYN activity in clinical PCa samples, suggesting a potential regulatory role of ASPA in modulating LYN signaling. Conclusion Our findings provide novel insights into the tumor-suppressive function of ASPA in PCa and highlight its potential as a prognostic biomarker and therapeutic target for the management of this malignancy.

Abstract The spinocerebellar ataxias (SCAs) are devastating neurological diseases characterized by progressive cerebellar incoordination. While neurons bear the brunt of the pathology, a growing body of evidence suggests that glial cells are also affected. It has, however, been difficult to understand the role of glia, given the diversity of subtypes, each with their individual contributions to neuronal health. Using human SCA autopsy samples we have discovered that Bergmann glia—the radial glia of the cerebellum, which form intimate functional connections with cerebellar Purkinje neurons—display inflammatory JNK-dependent c-Jun phosphorylation. This phosphorylation defines a signaling pathway not observed in other activated glial populations, providing an opportunity to isolate the role of Bergmann glia in SCA inflammation. Turning to an SCA1 mouse model as a paradigmatic SCA, we demonstrate that inhibiting the JNK pathway reduces Bergmann glia inflammation accompanied by improvements in the SCA1 phenotype both behaviorally and pathologically. These findings demonstrate the causal role for Bergmann glia inflammation in SCA1 and point to a novel therapeutic strategy that could span several ataxic syndromes where Bergmann glia inflammation is a major feature.

Abstract Background Chemoresistance is the main reason for the poor prognosis of pancreatic ductal adenocarcinoma (PDAC). Thus, there is an urgent need to screen out new targets and compounds to reverse chemotherapeutic resistance. Methods We established a bio-bank of human PDAC organoid models, covering a representative range of PDAC tumor subtypes. We screened a library of 1304 FDA-approved compounds to identify candidates efficiently overcoming chemotherapy resistance. The effects of the compounds were evaluated with a CellTiter-Glo-3D assay, organoid apoptosis assay and in vivo patient-derived xenograft (PDX), patient-derived organoid (PDO) and LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre (KPC) genetically engineered mouse models. RNA-sequencing, genome editing, sphere formation assays, iron assays and luciferase assays were conducted to elucidate the mechanism. Results High-throughput drug screening of chemotherapy-resistant PDOs identified irbesartan, an angiotensin ‖ type 1 (AT1) receptor antagonist, which could synergistically enhance the ability of chemotherapy to kill PDAC cells. In vitro and in vivo validation using PDO, PDX and KPC mouse models showed that irbesartan efficiently sensitized PDAC tumors to chemotherapy. Mechanistically, we found that irbesartan decreased c-Jun expression by inhibiting the Hippo/YAP1 pathway and further overcame chemotherapy resistance in PDAC. We also explored c-Jun, a potential target of irbesartan, which can transcriptionally upregulate the expression of key genes involved in stemness maintenance (SOX9/SOX2/OCT4) and iron metabolism (FTH1/FTL/TFRC). More importantly, we observed that PDAC patients with high levels of c-Jun expression demonstrated poor responses to the current standard chemotherapy regimen (gemcitabine plus nab-paclitaxel). Moreover, patients with PDAC had significant survival benefits from treatment with irbesartan plus a standard chemotherapy regimen in two-center retrospective clinical cohorts and patients with high c-Jun expression exhibited a better response to combination chemotherapy. Conclusions Irbesartan could be used in combination with chemotherapy to improve the therapeutic efficacy in PDAC patients with high levels of c-Jun expression. Irbesartan effectively inhibited chemotherapy resistance by suppressing the Hippo/YAP1/c-Jun/stemness/iron metabolism axis. Based on our findings, we are designing an investigator-initiated phase II clinical trial on the efficacy and safety of irbesartan plus a standard gemcitabine/nab-paclitaxel regimen in the treatment of patients with advanced III/IV staged PDAC and are hopeful that we will observe patient benefits.

Abstract Background Licorice (Glycyrrhiza uralensis Fisch.), a well-known traditional medicine, is traditionally used for the treatment of respiratory disorders, such as cough, sore throat, asthma and bronchitis. We aim to investigate the effects of liquiritin (LQ), the main bioactive compound in licorice against acute lung injury (ALI) and explore the potential mechanism. Methods Lipopolysaccharide (LPS) was used to induce inflammation in RAW264.7 cells and zebrafish. Intratracheal instillation of 3 mg/kg of LPS was used for induction an ALI mice model. The concentrations of IL-6 and TNF-α were tested using the enzyme linked immunosorbent assay. Western blot analysis was used to detect the expression of JNK/Nur77/c-Jun related proteins. Protein levels in bronchoalveolar lavage fluid (BALF) was measured by BCA protein assay. The effect of JNK on Nur77 transcriptional activity was determined by luciferase reporter assay, while electrophoretic mobility shift assay was used to examine the c-Jun DNA binding activity. Results LQ has significant anti-inflammatory effects in zebrafish and RAW264.7 cells. LQ inhibited the expression levels of p-JNK (Thr183/Tyr185), p-Nur77 (Ser351) and p-c-Jun (Ser63), while elevated the Nur77 expression level. Inhibition of JNK by a specific inhibitor or small interfering RNA enhanced the regulatory effect of LQ on Nur77/c-Jun, while JNK agonist abrogated LQ-mediated effects. Moreover, Nur77-luciferase reporter activity was suppressed after JNK overexpression. The effects of LQ on the expression level of c-Jun and the binding activity of c-Jun with DNA were attenuated after Nur77 siRNA treatment. LQ significantly ameliorated LPS-induced ALI with the reduction of lung water content and BALF protein content, the downregulation of TNF-α and IL-6 levels in lung BALF and the suppression of JNK/Nur77/c-Jun signaling, which can be reversed by a specific JNK agonist. Conclusion Our results indicated that LQ exerts significant protective effects against LPS-induced inflammation both in vivo and in vitro via suppressing the activation of JNK, and consequently inhibiting the Nur77/c-Jun signaling pathway. Our study suggests that LQ may be a potential therapeutic candidate for ALI and inflammatory disorders.

Transient receptor potential melastatin-8 (TRPM8) is a cation channel that is activated by cold and “cooling agents” such as menthol and icilin, which induce a cold sensation. The stimulation of TRPM8 activates an intracellular signaling cascade that ultimately leads to a change in the gene expression pattern of the cells. Here, we investigate the TRPM8-induced signaling pathway that links TRPM8 channel activation to gene transcription. Using a pharmacological approach, we show that the inhibition of phosphatidylinositol 4-phosphate 5 kinase α (PIP5K), an enzyme essential for the biosynthesis of phosphatidylinositol 4,5-bisphosphate, attenuates TRPM8-induced gene transcription. Analyzing the link between TRPM8 and Gq proteins, we show that the pharmacological inhibition of the βγ subunits impairs TRPM8 signaling. In addition, genetic studies show that TRPM8 requires an activated Gα subunit for signaling. In the nucleus, the TRPM8-induced signaling cascade triggers the activation of the transcription factor AP-1, a complex consisting of a dimer of basic region leucine zipper (bZIP) transcription factors. Here, we identify the bZIP protein c-Jun as an essential component of AP-1 within the TRPM8-induced signaling cascade. In summary, with PIP5K, Gq subunits, and c-Jun, we identified key molecules in TRPM8-induced signaling from the plasma membrane to the nucleus.

Background: Aristolochic acid nephropathy (AAN) is a rapidly progressive interstitial nephropathy caused by Aristolochic acid (AA). AAN is associated with the development of nephropathy and urothelial carcinoma. It is estimated that more than 100 million people worldwide are at risk of developing AAN. However, the underlying mechanisms driving renal deterioration in AAN remain poorly understood, and the treatment options are limited. Methods: We obtained GSE27168 and GSE136276 series matrix data from the Gene Expression Omnibus (GEO) related to AAN. Using the R Studio environment, we applied the limma package and WGCNA package to identify co-differently expressed genes (co-DEGs). By GO/KEGG/GSVA analysis, we revealed common biological pathways. Subsequently, co-DEGs were subjected to the String database to construct a protein-protein interaction (PPI) network. The MCC algorithms implemented in the Cytohubba plugin were employed to identify hub genes. The hub genes were cross-referenced with the transcription factor (TF) database to identify hub TFs. Immune infiltration analysis was performed to identify key immune cell groups by utilizing CIBERSORT. The expressions of AAN-associated hub TFs were verified in vivo and in vitro. Finally, siRNA intervention was performed on the two TFs to verify their regulatory effect in AAN. Results: Our analysis identified 88 co-DEGs through the “limma” and “WGCNA” R packages. A PPI network comprising 53 nodes and 34 edges was constructed with a confidence level >0.4. ATF3 and c-JUN were identified as hub TFs potentially linked to AAN. Additionally, expressions of ATF3 and c-JUN positively correlated with monocytes, basophils, and vessels, and negatively correlated with eosinophils and endothelial cells. We observed a significant increase in protein and mRNA levels of these two hub TFs. Furthermore, it was found that siRNA intervention targeting ATF3, but not c-JUN, alleviated cell damage induced by AA. The knockdown of ATF3 protects against oxidative stress and inflammation in the AAN cell model. Conclusion: This study provides novel insights into the role of ATF3 in AAN. The comprehensive analysis sheds light on the molecular mechanisms and identifies potential biomarkers and drug targets for AAN treatment.

Background: Maintaining the repair phenotype of denervated Schwann cells in the injured distal nerve is crucial for promoting peripheral nerve regeneration. However, when chronically denervated, the capacity of Schwann cells to support repair and regeneration deteriorates, leading to peripheral nerve regeneration and poor functional recovery. Herein, we investigated whether neurotrophin-3 (NT-3) could sustain the reparative phenotype of Schwann cells and promote peripheral nerve regeneration after chronic denervation and aimed to uncover its potential molecular mechanisms. Methods: Western blot was employed to investigate the relationship between the expression of c-Jun and the reparative phenotype of Schwann cells. The inducible expression of c-Jun by NT-3 was examined both in vitro and in vivo with western blot and immunofluorescence staining. A chronic denervation model was established to study the role of NT-3 in peripheral nerve regeneration. The number of regenerated distal axons, myelination of regenerated axons, reinnervation of neuromuscular junctions, and muscle fiber diameters of target muscles were used to evaluate peripheral nerve regeneration by immunofluorescence staining, transmission electron microscopy (TEM), and hematoxylin and eosin (H&E) staining. Adeno-associated virus (AAV) 2/9 carrying shRNA, small molecule inhibitors, and siRNA were employed to investigate whether NT-3 could signal through the TrkC/ERK pathway to maintain c-Jun expression and promote peripheral nerve regeneration after chronic denervation. Results: After peripheral nerve injury, c-Jun expression progressively increased until week 5 and then began to decrease in the distal nerve following denervation. NT-3 upregulated the expression of c-Jun in denervated Schwann cells, both in vitro and in vivo. NT-3 promoted peripheral nerve regeneration after chronic denervation, mainly by upregulating or maintaining a high level of c-Jun rather than NT-3 itself. The TrkC receptor was consistently presented on denervated Schwann cells and served as NT-3 receptors following chronic denervation. NT-3 mainly upregulated c-Jun through the TrkC/ERK pathway. Conclusion: NT-3 promotes peripheral nerve regeneration by maintaining the repair phenotype of Schwann cells after chronic denervation via the TrkC/ERK/c-Jun pathway. It provides a potential target for the clinical treatment of peripheral nerve injury after chronic denervation. [ABSTRACT FROM AUTHOR]

The development of effective therapies and biomarkers for pancreatic cancer is an unmet clinical need. To address this, we have developed an easy-to-use pancreatic cancer rat animal model via pancreas-targeted hydrodynamic gene delivery of human pancreatic cancer-related genes. Our study aimed to determine the molecular similarity between the pancreatic tumor in the rat model and human pancreatic cancer. KRAS G12D gene-expressing plasmid was delivered to the pancreas of wild type rats via pancreas-targeted hydrodynamic gene delivery as previously reported. Tissue samples were collected at 5 weeks after the first gene delivery. The tumors developed in the rats were assessed for the expression of oncogenic proteins that are involved in human pancreatic cancer development. The development of a tumor mimicking pancreatic ductal adenocarcinoma was confirmed. The expression levels of Cyclin D1, c-Jun, IL-33, and Zip4 proteins in the tumor were immunohistochemically assessed and the correlation of the proteins was confirmed. The expression pattern showed similarity to that of surgically resected human pancreatic cancer tissues. Our study findings showing a similar pattern of oncogenic protein expression in novel KRAS G12D gene-induced rat pancreatic cancer model and human pancreatic cancer will be useful for establishing novel tumor markers and therapeutic options for pancreatic cancer. [Display omitted] • Pancreas-targeted KRAS G12D gene delivery developed pancreatic cancer in rats. • The pancreatic tumors in the rats showed similar histological character to that of human pancreatic cancer. • Various oncogenic pathways are activated in the rats' pancreatic cancer similar to that of human pancreatic cancer. • Expressions of Cyclin D1, c-Jun, IL-33, and Zip4 protein showed significant correlation. [ABSTRACT FROM AUTHOR]

Pulmonary inflammation induced by cigarette smoke (CS) promoted the development of chronic obstructive pulmonary disease (COPD), and macrophage polarization caused by CS modulated inflammatory response. Previous studies indicated that salidroside exerted therapeutic effects in COPD, but the anti‐inflammatory mechanisms were not clear. This study aimed to explore the effects and mechanisms of salidroside on macrophage polarization induced by CS. Wistar rats received passively CS exposure and were treated intraperitoneally with salidroside at a low, medium or high dose. Lung tissues were stained with hematoxylin–eosin. Emphysema and inflammatory scores were evaluated by histomorphology. Lung function, cytokines, and cell differential counts in BALF were detected. The macrophage polarization was determined by immunohistochemistry in lung tissues. Alveolar macrophages (AMs) were isolated and treated with cigarette smoke extract (CSE), salidroside or inhibitors of relative pathways. The polarization status was determined by qPCR, and the protein level was detected by Western blotting. CS exposure induced emphysema and lung function deterioration. The inflammatory scores, cytokines level and neutrophils counts were elevated after CS exposure. Salidroside treatment partly ameliorated above abnormal. CS exposure activated M1 and M2 polarization of AMs in vivo and in vitro, and salidroside mitigated M1 polarization induced by CS. CSE activated the JNK/c‐Jun in AMs and the M1 polarization of AMs was inhibited by the inhibitors of JNK and AP‐1. Salidroside treatment deactivated the JNK/c‐Jun, which indicated that salidroside mitigated the M1 polarization of AMs induced by CS via inhibiting JNK/c‐Jun. Salidroside treatment ameliorated the pulmonary inflammation and M1 polarization of AMs induced by CS, and the process might be mediated by the deactivation of JNK/c‐Jun. [ABSTRACT FROM AUTHOR]

Background: Peritoneal fibrosis is a common complication of peritoneal dialysis, which may lead to ultrafiltration failure and ultimately treatment discontinuation. LncRNAs participate in many biological processes during tumorigenesis. We investigated the role of AK142426 in peritoneal fibrosis. Methods: The AK142426 level in peritoneal dialysis (PD) fluid was detected by quantitative real‐time‐PCR assay. The M2 macrophage distribution was determined by flow cytometry. The inflammatory cytokines of TNF‐α and TGF‐β1 were measured by ELISA assay. The direct interaction between AK142426 and c‐Jun was evaluated by RNA pull‐down assay. In addition, the c‐Jun and fibrosis related proteins were assessed by western blot analysis. Results: The PD‐induced peritoneal fibrosis mouse model was successfully established. More importantly, PD treatment induced M2 macrophage polarization and the inflammation in PD fluid, which might be associated with exosome transmission. Fortunately, AK142426 was observed to be upregulated in PD fluid. Mechanically, knockdown of AK142426 suppressed M2 macrophage polarization and inflammation. Furthermore, AK142426 could upregulate c‐Jun through binding c‐Jun protein. In rescue experiments, overexpression of c‐Jun could partially abolish the inhibitory effect of sh‐AK142426 on the activation of M2 macrophages and inflammation. Consistently, knockdown of AK142426 alleviated peritoneal fibrosis in vivo. Conclusions: This study demonstrated that knockdown of AK142426 suppressed M2 macrophage polarization and inflammation in peritoneal fibrosis via binding to c‐Jun, suggesting that AK142426 might be a promising therapeutic target for patients of peritoneal fibrosis. [ABSTRACT FROM AUTHOR]