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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]

Uveitis is a vision-threatening disease primarily driven by a dysregulated immune response, with retinal microglia playing a pivotal role in its progression. Although the transcription factor EGR2 is known to be closely associated with uveitis, including Vogt-Koyanagi-Harada disease and Behcet's disease, and is essential for maintaining the dynamic homeostasis of autoimmunity, its exact role in uveitis remains unclear. In this study, diminished EGR2 expression was observed in both retinal microglia from experimental autoimmune uveitis (EAU) mice and inflammation-induced human microglia cell line (HMC3). We constructed a mice model with conditional knockout of EGR2 in microglia and found that EGR2 deficiency resulted in increased intraocular inflammation. Meanwhile, EGR2 overexpression downregulated the expression of inflammatory cytokines as well as cell migration and proliferation in HMC3 cells. Next, RNA sequencing and ChIP-PCR results indicated that EGR2 directly bound to its downstream target growth differentiation factor 15 (GDF15) and further regulated GDF15 transcription. Furthermore, intravitreal injection of GDF15 recombinant protein was shown to ameliorate EAU progression in vivo. Meanwhile, knockdown of GDF15 reversed the phenotype of EGR2 overexpression-induced microglial inflammation in vitro. In summary, this study highlighted the protective role of the transcription factor EGR2 in AU by modulating the microglial phenotype. GFD15 was identified as a downstream target of EGR2, providing a unique target for uveitis treatment. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) is a serious health problem worldwide, which ultimately leads to end-stage renal disease (ESRD). Renal fibrosis is the common pathway and major pathological manifestation for various CKD proceeding to ESRD. However, the underlying mechanisms and effective therapies are still ambiguous. Early growth response 2 (EGR2) is reportedly involved in organ formation and cell differentiation. To determine the role of EGR2 in renal fibrosis, we respectively confirmed the increased expression of EGR2 in kidney specimens from both CKD patients and mice with location in proximal tubules. Genetic deletion of EGR2 attenuated obstructive nephropathy while EGR2 overexpression further promoted renal fibrosis in mice subjected to unilateral ureteral obstruction (UUO) due to extracellular matrix (ECM) deposition mediating by partial epithelial-mesenchymal transition (EMT) as well as imbalance between matrix metalloproteinases (MMPs) and tissue inhibitor of MMPs (TIMPs). We found that EGR2 played a critical role in Smad3 phosphorylation, and inhibition of EGR2 reduced partial EMT leading to blockade of ECM accumulation in cultured human kidney 2 cells (HK2) treated with transforming growth factor β1 (TGF-β1). In addition, the transcription co-stimulator signal transducer and activator of transcription 3 (STAT3) phosphorylation was confirmed to regulate the transcription level of EGR2 in TGF-β1-induced HK2 cells. In conclusion, this study demonstrated that EGR2 played a pathogenic role in renal fibrosis by a p-STAT3-EGR2-p-Smad3 axis. Thus, targeting EGR2 could be a promising strategy for CKD treatment. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cells are critical to the innate immune system, as they recognize antigens without prior sensitization, and contribute to the control and clearance of viral infections and cancer. However, a significant proportion of NK cells in mice and humans do not express classical inhibitory receptors during their education process and are rendered naturally "anergic", i.e., exhibiting reduced effector functions. The molecular events leading to NK cell anergy as well as their relation to those underlying NK cell exhaustion that arises from overstimulation in chronic conditions, remain unknown. Here, we characterize the "anergic" phenotype and demonstrate functional, transcriptional, and phenotypic similarities to the "exhausted" state in tumor-infiltrating NK cells. Furthermore, we identify zinc finger transcription factor Egr2 and diacylglycerol kinase DGKα as common negative regulators controlling NK cell dysfunction. Finally, experiments in a 3D organotypic spheroid culture model and an in vivo tumor model suggest that a nanoparticle-based delivery platform can reprogram these dysfunctional natural killer cell populations in their native microenvironment. This approach may become clinically relevant for the development of novel anti-tumor immunotherapeutic strategies. Synopsis: The mechanisms underlying naturally occurring "anergic" and overstimulation-induced "exhausted" states of natural killer (NK) cells remain unclear. This study identifies common functional and phenotypic characteristics of these two dysfunctional states, and identifies common regulators that can be targeted to reprogram dysfunctional NK cells. The transcription factor Egr2 and diacylglycerol kinase DGKα regulate both dysfunctional states of NK cells. Egr2 silencing rescues anergic NK cell cytotoxicity via the EGR2-DGKα-MAPK-pERK axis, potentially modulating SHP-1 activity and calcium levels. Naturally occurring anergic NK cells have functional, transcriptional, and phenotypic similarities to exhausted NK cells within the tumor microenvironment. A nanoparticle-based method can reprogram dysfunctional NK cells in their native milieu and increase their anti-tumor activity. Common intrinsic regulators of dysfunctional "anergic" and "exhausted" NK cells can be targeted to restore cytotoxicity. [ABSTRACT FROM AUTHOR]

Background: Immediate early genes (IEGs) are rapidly activated and initiate diverse cellular processes including neuroplasticity. We report the effect of psilocybin (PSIL), PSIL-containing psychedelic mushroom extract (PME) and 5-hydroxytryptophan (5-HTP) on expression of the IEGs, cfos, egr1, and egr2 in mouse somatosensory cortex (SSC). Methods: In our initial experiment, male C57Bl/6j mice were injected with PSIL 4.4 mg/kg or 5-HTP 200 mg/kg, alone or immediately preceded by serotonergic receptor modulators. IEG mRNA expression 1 hour later was determined by real time qPCR. In a replication study a group of mice treated with PME was added. Results: In our initial experiment, PSIL but not 5-HTP significantly increased expression of all three IEGs. No correlation was observed between the head twitch response (HTR) induced by PSIL and its effect on the IEGs. The serotonergic receptor modulators did not significantly alter PSIL-induced IEG expression, with the exception of the 5-HT2C antagonist (RS102221), which significantly enhanced PSIL-induced egr2 expression. 5-HTP did not affect IEG expression. In our replication experiment, PSIL and PME upregulated levels of egr1 and cfos while the upregulation of egr2 was not significant. Conclusions: We have shown that PSIL and PME but not 5-HTP (at a dose sufficient to induce HTR), induced a significant increase in cfos and egr1 expression in mouse SSC. Our findings suggest that egr1 and cfos expression may be associated with psychedelic effects. [ABSTRACT FROM AUTHOR]

Abstract Alzheimer’s disease (AD) is the major form of dementia prevalent in older adults and with a high incidence in females. Identification of early biomarkers is essential for preventive intervention to delay its progression. Furthermore, due to its multifactorial nature, a multi-target approach could be therapeutically beneficial. Our studies included 4- (pre-pathology) and 11-month (mild-pathology) TgF344-AD rats, a transgenic Alzheimer’s model that exhibits age-dependent AD progression. We identified two potential early biomarker genes for AD, early growth response 2 (EGR2) and histone 1H2AA (HIST1H2AA), in the hippocampus of 4-month females. Out of 17,168 genes analyzed by RNA sequencing, expression of these two genes was significantly altered in 4-month TgF344-AD rats compared to wild-type littermates. We also evaluated co-treatment with diazoxide (DZ), a potassium channel activator, and dibenzoylmethane (DIB), which inhibits eIF2α-P activity, on TgF344-AD and wild-type rats. DZ/DIB-treatment mitigated spatial memory deficits and buildup of hippocampal Aβ plaques and tau PHF in 11-month TgF344-AD rats but had no effect on wild-type littermates. To our knowledge, this preclinical study is the first to report EGR2 and HIST1H2AA as potential AD biomarkers in females, and the benefits of DZ/DIB-treatment in AD. Evaluations across multiple AD-related models is warranted to corroborate our findings.

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.

Summary: During abscisic acid (ABA) signaling, reversible phosphorylation controls the activity and accumulation of class III SNF1‐RELATED PROTEIN KINASE 2s (SnRK2s). While protein phosphatases that negatively regulate SnRK2s have been identified, those that positively regulate ABA signaling through SnRK2s are less understood.In this study, Arabidopsis thaliana mutants of Clade E Growth‐Regulating 1 and 2 (EGR1/2), which belong to the protein phosphatase 2C family, exhibited reduced ABA sensitivity in terms of seed germination, cotyledon greening, and ABI5 accumulation. Conversely, overexpression increased these ABA‐induced responses. Transcriptomic data revealed that most ABA‐regulated genes in egr1 egr2 plants were expressed at reduced levels compared with those in Col‐0 after ABA treatment.Abscisic acid up‐regulated EGR1/2, which interact directly with SnRK2.2 through its C‐terminal domain I. Genetic analysis demonstrated that EGR1/2 function through SnRK2.2 during ABA response. Furthermore, SnRK2.2 de‐phosphorylation by EGR1/2 was identified at serine 31 within the ATP‐binding pocket. A phospho‐mimic mutation confirmed that phosphorylation at serine 31 inhibited SnRK2.2 activity and reduced ABA responsiveness in plants.Our findings highlight the positive role of EGR1/2 in regulating ABA signaling, they reveal a new mechanism for modulating SnRK2.2 activity, and provide novel insight into how plants fine‐tune their responses to ABA. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the major form of dementia prevalent in older adults and with a high incidence in females. Identification of early biomarkers is essential for preventive intervention to delay its progression. Furthermore, due to its multifactorial nature, a multi-target approach could be therapeutically beneficial. Our studies included 4- (pre-pathology) and 11-month (mild-pathology) TgF344-AD rats, a transgenic Alzheimer's model that exhibits age-dependent AD progression. We identified two potential early biomarker genes for AD, early growth response 2 (EGR2) and histone 1H2AA (HIST1H2AA), in the hippocampus of 4-month females. Out of 17,168 genes analyzed by RNA sequencing, expression of these two genes was significantly altered in 4-month TgF344-AD rats compared to wild-type littermates. We also evaluated co-treatment with diazoxide (DZ), a potassium channel activator, and dibenzoylmethane (DIB), which inhibits eIF2α-P activity, on TgF344-AD and wild-type rats. DZ/DIB-treatment mitigated spatial memory deficits and buildup of hippocampal Aβ plaques and tau PHF in 11-month TgF344-AD rats but had no effect on wild-type littermates. To our knowledge, this preclinical study is the first to report EGR2 and HIST1H2AA as potential AD biomarkers in females, and the benefits of DZ/DIB-treatment in AD. Evaluations across multiple AD-related models is warranted to corroborate our findings. [ABSTRACT FROM AUTHOR]

Pelvic organ prolapse (POP) is a common disorder among women that negatively affects women's quality of life. Early growth response 2 (EGR2) is a transcription factor that regulates cell growth. The present study aimed to explore the role of EGR2 in POP progression and provided a new target for the treatment and prevention of POP. Firstly, we extracted primary vaginal anterior wall fibroblasts from POP tissues and non-POP tissues and then constructed an EGR2-silencing lentivirus for further study. Immunoblotting, qPCR, TUNEL assay, CCK-8 assay, dual luciferase assay, and ELISA assay were carried out. EGR2 expression was much higher in POP tissues than in control tissues, and EGR2 expression positively correlated with cytokine signaling 3 (SOCS3) expression. Knockdown of EGR2 increased cell proliferation, upregulated PCNA expression, and reduced apoptosis in POP fibroblasts. Moreover, we found that the knockdown of EGR2 increased COL1A1, COL3A1, and Elastin expression and decreased MMP2 and MMP9 activities, and knockdown of EGR2 increased TGF-β/Smad pathway activity in POP fibroblasts. Interestingly, the results of dual luciferase assay demonstrated that EGR2 was able to increase SOCS3 transcriptional activity. EGR2 knockdown alleviated the apoptosis of POP fibroblasts by reducing SOCS3 expression and improving the proliferation and collagen synthesis of POP fibroblasts. Overall, our study illustrated that EGR2 was highly expressed in POP tissues, and knockdown of EGR2 alleviated apoptosis and reduced matrix degradation in POP fibroblasts. This study might provide a new insight into the pathogenesis of POP. [ABSTRACT FROM AUTHOR]

Senescence, a state of stable growth arrest, plays an important role in ageing and age-related diseases in vivo. Although the INK4/ARF locus is known to be essential for senescence programmes, the key regulators driving p16 and ARF transcription remain largely underexplored. Using siRNA screening for modulators of the p16/pRB and ARF/p53/p21 pathways in deeply senescent human mammary epithelial cells (DS HMECs) and fibroblasts (DS HMFs), we identified EGR2 as a novel regulator of senescence. EGR2 expression is up-regulated during senescence, and its ablation by siRNA in DS HMECs and HMFs transiently reverses the senescent phenotype. We demonstrate that EGR2 activates the ARF and p16 promoters and directly binds to both the ARF and p16 promoters. Loss of EGR2 down-regulates p16 levels and increases the pool of p16- p21- 'reversed' cells in the population. Moreover, EGR2 overexpression is sufficient to induce senescence. Our data suggest that EGR2 is a direct transcriptional activator of the p16/pRB and ARF/p53/p21 pathways in senescence and a novel marker of senescence.

Background: Mutations in the Early‐Growth Response 2 (EGR2) gene cause various hereditary neuropathies, including demyelinating Charcot–Marie‐Tooth (CMT) disease type 1D (CMT1D), congenital hypomyelinating neuropathy type 1 (CHN1), Déjerine–Sottas syndrome (DSS), and axonal CMT (CMT2). Methods: In this study, we identified 14 patients with heterozygous EGR2 mutations diagnosed between 2000 and 2022. Results: Mean age was 44 years (15–70), 10 patients were female (71%), and mean disease duration was 28 years (1–56). Disease onset was before age 15 years in nine cases (64%), after age 35 years in four cases (28%), and one patient aged 26 years was asymptomatic (7%). All symptomatic patients had pes cavus and distal lower limbs weakness (100%). Distal lower limbs sensory symptoms were observed in 86% of cases, hand atrophy in 71%, and scoliosis in 21%. Nerve conduction studies showed a predominantly demyelinating sensorimotor neuropathy in all cases (100%), and five patients needed walking assistance after a mean disease duration of 50 years (47–56) (36%). Three patients were misdiagnosed as inflammatory neuropathy and treated with immunosuppressive drugs for years before diagnosis was corrected. Two patients presented with an additional neurologic disorder, including Steinert's myotonic dystrophy and spinocerebellar ataxia (14%). Eight EGR2 gene mutations were found, including four previously undescribed. Interpretation.: Our findings demonstrate EGR2 gene‐related hereditary neuropathies are rare and slowly progressive demyelinating neuropathies with two major clinical presentations, including a childhood‐onset variant and an adult‐onset variant which may mimic inflammatory neuropathy. Our study also expands the genotypic spectrum of EGR2 gene mutations. [ABSTRACT FROM AUTHOR]

Summary: Our laboratory has a long‐standing research interest in understanding how lipid‐activated transcription factors, nuclear hormone receptors, contribute to dendritic cell and macrophage gene expression regulation, subtype specification, and responses to a changing extra and intracellular milieu. This journey in the last more than two decades took us from identifying target genes for various RXR heterodimers to systematically mapping nuclear receptor‐mediated pathways in dendritic cells to identifying hierarchies of transcription factors in alternative polarization in macrophages to broaden the role of nuclear receptors beyond strictly ligand‐regulated gene expression. We detail here the milestones of the road traveled and draw conclusions regarding the unexpectedly broad role of nuclear hormone receptors as epigenomic components of dendritic cell and macrophage gene regulation as we are getting ready for the next challenges. [ABSTRACT FROM AUTHOR]

[ Objective]The study aimed to clone the CDS region of EGR2 gene transcript XI (EGR2-XI) of bovine, detect the expression patterns of EGR2-XI in different tissues and preadipocytes of different differentiation degrees, and predict the structure and function of its encoded protein. [Method] CDS region of EGR2-XI gene was cloned by PCR and sequencing techniques. Then, preadipocytes were isolated by collagenase digestion. In addition, the expression level of EGR2-XI gene was detected in 7 tissues ( heart, liver, spleen, lung, kidney, muscle and back fat) and during preadipocytes differentiation by RT-qPCR. At the same time, the physicochemical properties and protein structures of EGR2-XI were analyzed by ProtParam, Phyre2, NetPhos 3.1 and other software. [Result]The CDS region of bovine EGR2-XI was successfully cloned and it was 1458 hp in length. It encoded an unstable 485 amino acid hydrophilic protein without transmembrane structures and signal peptides. The protein contained three typical zinc finger domains, and its amino acids were mainly composed of irregular coiled and extended chains, which mainly played roles in the nucleus. At the same time, the prediction of protein interaction network found that EGR2-Xl may interact with SOXI0, EGRl, EGR3 and other proteins. Phylogenetic tree analysis showed that the genetic relationship between bovine and buffalo was the closest, and zebrafish was the farthest. It was indicated that EGR2-Xl protein was highly conserved among different species. EGR2-Xl gene was expressed in heart, liver, spleen, lung, kidney, muscle and back fat, with the highest expression in the lung, followed by back fat and liver, and the lowest in kidney. The expression level of EGR2-Xl gene was the highest on the 3nl day, then gradually decreased, and the lowest on the 7th day. [ Conclusion]EGR2-XJ plays an important role in regulating the proliferation, differentiation and lipid metabolism of bovine adipocytes. [ABSTRACT FROM AUTHOR]

Alternative polarization of macrophages induced by IL-4 is important for homeostasis and tissue repair. Downstream from IL-4 receptor signaling, STAT6 activation is transient, but induces stable transcriptional changes. These data suggest that STAT6 induces second messengers to carry out the alternative transcriptional program. In this issue of Genes & Development, Daniel and colleagues (pp. 1474-1492) identify EGR2 as a downstream regulator of STAT6 with broad functionality that further induces many transcription factors associated with alternative polarization. Identification of high EGR2 expression in a subset of mouse and human alveolar macrophages further highlights EGR2 as a conserved marker of alternatively activated macrophages.

Introduction: Macrophages significantly contribute to the regulation of vessel formation under physiological and pathological conditions. Although the angiogenesis-regulating role of alternatively polarized macrophages is quite controversial, a growing number of evidence shows that they can participate in the later phases of angiogenesis, including vessel sprouting and remodeling or regression. However, the epigenetic and transcriptional regulatory mechanisms controlling this angiogenesis-modulating program are not fully understood. Results: Here we show that IL-4 can coordinately regulate the VEGFA-VEGFR1 (FLT1) axis via simultaneously inhibiting the proangiogenic Vegfa and inducing the antiangiogenic Flt1 expression in murine bone marrow-derived macrophages, which leads to the attenuated proangiogenic activity of alternatively polarized macrophages. The IL-4-activated STAT6 and IL-4-STAT6 signaling pathway-induced EGR2 transcription factors play a direct role in the transcriptional regulation of the Vegfa-Flt1 axis. We demonstrated that this phenomenon is not restricted to the murine bone marrow-derived macrophages, but can also be observed in different murine tissue-resident macrophages ex vivo and parasites-elicited macrophages in vivo with minor cell type-specific differences. Furthermore, IL-4 exposure can modulate the hypoxic response of genes in both murine and human macrophages leading to a blunted Vegfa/VEGFA and synergistically induced Flt1/FLT1 expression. Discussion: Our findings establish that the IL-4-activated epigenetic and transcriptional program can determine angiogenesis-regulating properties in alternatively polarized macrophages under normoxic and hypoxic conditions. [ABSTRACT FROM AUTHOR]

Although T cells can develop into an exhausted state in the tumour microenvironment, tumour infiltrating T cells (TILs) are important to control tumour growth. By analysing single cell RNA-sequencing data from human tumours, we found that the transcription factors Early Growth Response 2 (EGR2) and 3 were highly induced in TILs, but not peripheral CD8 + T cells, in multiple patient cohorts. We found that deficiency of Egr2 and 3 in T cells resulted in enhanced tumour growth and fewer TILs in mouse models. Egr2 is highly expressed together with checkpoint molecules in a proportion of CD8 + TILs and Egr2high cells exhibit better survival and proliferation than Egr2-/-Egr3-/- and Egr2low TILs. Anti-PD-1 treatment increases Egr2 expression in CD8 + TILs and reduces tumour growth, while anti-PD-1 efficacy is abrogated in the absence of Egr2 and 3. Thus, Egr2 and 3 are important for maintaining anti-tumour responses of exhausted CD8 + TILs. [ABSTRACT FROM AUTHOR]

Abstract Background Myocardial infarction (MI) is characterized by coronary artery occlusion, ischemia and hypoxia of myocardial cells, leading to irreversible myocardial damage. Therefore, it is urgent to explore the potential mechanism of myocardial injury during the MI process to develop effective therapies for myocardial cell rescue. Methods We downloaded the GSE71906 dataset from GEO DataSets, and the R software was used to identify the differentially expressed genes (DEGs) in mouse heart tissues of MI and sham controls. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were performed to understand the significantly activated signaling pathways in MI. Protein–protein interaction (PPI) network was constructed to highlight the hub genes in DEGs. The Western Blot, qRT-PCR and TUNEL staining were used to explore the function of hub gene in hypoxia-induced cardiomyocytes in vitro. Results A total of 235 DEGs were identified in GSE71906 dataset. Functional enrichment analysis revealed that the upregulated genes were primarily associated with the inflammatory response and apoptosis. 20 hub genes were identified in PPI network, and the early growth response 2 (EGR2) was highlighted. In vitro. We confirmed the EGR2 was upregulated induced by hypoxia and revealed the upregulated EGR2 aggravates pro-inflammation and pro-apoptotic genes expression. In addition, EGR2 knockout mitigates hypoxia-induced inflammation and apoptosis in cardiomyocytes. Conclusion The present study identified the EGR2 was a hub gene in myocardial damage during MI process, the excessive EGR2 aggravates hypoxia-induced myocardial damage by accelerating inflammation and apoptosis in vitro. Therefore, targeting EGR2 offers a potential pharmacological strategy for myocardial cell rescue in MI.

Rett syndrome (RTT) is a severe neurodevelopmental disease caused almost exclusively by mutations to the MeCP2 gene. This disease may be regarded as a synaptopathy, with impairments affecting synaptic plasticity, inhibitory and excitatory transmission and network excitability. The complete understanding of the mechanisms behind how the transcription factor MeCP2 so profoundly affects the mammalian brain are yet to be determined. What is known, is that MeCP2 involvement in activity-dependent expression programs is a critical link between this protein and proper neuronal activity, which allows the correct maturation of connections in the brain. By using RNA-sequencing analysis, we found several immediate-early genes (IEGs, key mediators of activity-dependent responses) directly bound by MeCP2 at the chromatin level and upregulated in the hippocampus and prefrontal cortex of the Mecp2-KO mouse. Quantification of the IEGs response to stimulus both in vivo and in vitro detected an aberrant expression pattern in MeCP2-deficient neurons. Furthermore, altered IEGs levels were found in RTT patient's peripheral blood and brain regions of post-mortem samples, correlating with impaired expression of downstream myelination-related genes. Altogether, these data indicate that proper IEGs expression is crucial for correct synaptic development and that MeCP2 has a key role in the regulation of IEGs. [ABSTRACT FROM AUTHOR]

Exosomes generated by BMSCs contribute to functional recovery in ischemic stroke. However, the regulatory mechanism is largely unknown. Exosomes were isolated from BMSCs. Tube formation, MTT, TUNEL, and flow cytometry assays were applied to examine cell angiogenesis, viability, and apoptosis. Protein and DNA interaction was evaluated by ChIP and luciferase assays. LDH release into the culture medium was examined. Infarction area was evaluated by TTC staining. Immunofluorescence staining was applied to examine CD31 expression. A mouse model of MCAO/R was established. BMSC-derived exosomes attenuated neuronal cell damage and facilitated angiogenesis of brain endothelial cells in response to OGD/R, but these effects were abolished by the knockdown of Egr2. Egr2 directly bound to the promoter of SIRT6 to promote its expression. The incompetency of Egr2-silencing exosomes was reversed by overexpression of SIRT6. Furthermore, SIRT6 inhibited Notch signaling via suppressing Notch1. Overexpression of SIRT6 and inhibition of Notch signaling improved cell injury and angiogenesis in OGD/R-treated cells. BMSC-derived exosomal Egr2 ameliorated MCAO/R-induced brain damage via upregulating SIRT6 to suppress Notch signaling in mice. BMSC-derived exosomes ameliorate OGD/R-induced injury and MCAO/R-caused cerebral damage in mice by delivering Egr2 to promote SIRT6 expression and subsequently suppress Notch signaling. Our study provides a potential exosome-based therapy for ischemic stroke. [ABSTRACT FROM AUTHOR]

Fat mass and obesity-associated protein (FTO) is a demethylase and plays a vital role in various cancers. However, the regulation mechanism of FTO in prostate cancer (PCa) remains unclear. This study aimed to elucidate the mechanism of FTO in PCa. The function and mechanism of FTO-mediated in PCa were determined by gain-of-function assays and RNA-seq. We found that FTO expression in PCa tissues and two PCa cell lines were significantly lower than that in adjacent tissues and normal cell line. PCa cells after overexpression of FTO showed a significant lower in proliferation, migration, and invasion capabilities. RNA-seq displayed that FTO overexpression altered transcriptome landscape in Du145 and PC-3 cells, particularly upregulating EGR2 expression. FTO overexpression induced differential expression genes, including MYLK2, DNA2, CDK, and CDC (6, 7, 20, 25, and 45), which were mainly enriched in adjustment of cell cycle and growth pathways. Furthermore, FTO overexpression significantly reduced the EGR2 methylation level. Arresting the proliferation, migration, and invasion of Du145 cells induced by FTO overexpression was significantly rescued by EGR2 knockdown. FTO overexpression also significantly inhibited tumor growth and promoted EGR2 protein expression. Taken together, FTO suppresses PCa progression by regulating EGR2 methylation. We uncovered a novel regulatory mechanism of FTO in PCa and provide a new potential therapeutic target for PCa. [ABSTRACT FROM AUTHOR]

Pathogen-induced memory Tfh cells are important to maintain high-affinity antibodies against pathogens. We have now discovered Tfh cells with a similar memory phenotype (MP) that develop in pathogen-free conditions. These MP Tfh cells are similar to pathogen-induced memory Tfh in both phenotype and function. They express FR4 and Egr2, which are both found in pathogen-induced memory Tfh cells. FR4 + Egr2 + CD4 MP cells express genes involved in the development of Tfh cells and homeostatic proliferation, as well as key metabolic pathways discovered in pathogen-induced memory Tfh cells. MP Tfh cells can support B cell-mediated IgG production in vitro and induce germinal center formation and anti-viral antibodies in response to virus infection. These mouse MP Tfh cells share a similar phenotype to human circulating Tfh cells that are increased in Sjögren's syndrome patients. Although Foxp3-positive circulating T follicular regulatory (Tfr) cells are normal, a proportion of circulating Tfh cells from patients express increased levels of T-bet, which is associated with high levels of inflammatory pathology. Thus, although they do not require overt infection for their development, MP Tfh cells are important for protective immune responses, and dysregulated MP Tfh responses may play a role in autoimmunity., (© 2024 The Author(s). European Journal of Immunology published by Wiley‐VCH GmbH.)

Autologous macrophage transfer is an emerging platform for cell therapy. It is anticipated that conventional macrophage reprogramming based on ex vivo polarization using cytokines and ligands of TLRs may enhance the therapeutic effect. We describe an alternative approach based on small interfering RNA (siRNA) knockdown of selected molecular cues of macrophage polarization, namely EGR2, IRF3, IRF5, and TLR4 in Raw264.7 monocyte/macrophage cell line and mouse-bone-marrow-derived macrophages (BMDMs). The impact of IRF5 knockdown was most pronounced, curtailing the expression of other inflammatory mediators such as IL-6 and NOS2, especially in M1-polarized macrophages. Contrary to IRF5, EGR2 knockdown potentiated M1-associated markers while altogether abolishing M2 marker expression, which is indicative of the principal role of EGR2 in the maintenance of alternative phenotypes. IRF3 knockdown suppressed M1 polarization but upregulated Arg 1, a canonical marker of alternative polarization in M1 macrophages. As anticipated, the knockdown of TLR4 also attenuated the M1 phenotype but, akin to IRF3, significantly induced Arginase 1 in M0 and M1, driving the phenotype towards M2. This study validates RNAi as a viable option for the alteration and maintenance of macrophage phenotypes. [ABSTRACT FROM AUTHOR]

Background: Myocardial infarction (MI) is characterized by coronary artery occlusion, ischemia and hypoxia of myocardial cells, leading to irreversible myocardial damage. Therefore, it is urgent to explore the potential mechanism of myocardial injury during the MI process to develop effective therapies for myocardial cell rescue.Methods: We downloaded the GSE71906 dataset from GEO DataSets, and the R software was used to identify the differentially expressed genes (DEGs) in mouse heart tissues of MI and sham controls. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were performed to understand the significantly activated signaling pathways in MI. Protein-protein interaction (PPI) network was constructed to highlight the hub genes in DEGs. The Western Blot, qRT-PCR and TUNEL staining were used to explore the function of hub gene in hypoxia-induced cardiomyocytes in vitro.Results: A total of 235 DEGs were identified in GSE71906 dataset. Functional enrichment analysis revealed that the upregulated genes were primarily associated with the inflammatory response and apoptosis. 20 hub genes were identified in PPI network, and the early growth response 2 (EGR2) was highlighted. In vitro. We confirmed the EGR2 was upregulated induced by hypoxia and revealed the upregulated EGR2 aggravates pro-inflammation and pro-apoptotic genes expression. In addition, EGR2 knockout mitigates hypoxia-induced inflammation and apoptosis in cardiomyocytes.Conclusion: The present study identified the EGR2 was a hub gene in myocardial damage during MI process, the excessive EGR2 aggravates hypoxia-induced myocardial damage by accelerating inflammation and apoptosis in vitro. Therefore, targeting EGR2 offers a potential pharmacological strategy for myocardial cell rescue in MI. [ABSTRACT FROM AUTHOR]

Fibrotic diseases contribute to 45% of deaths in the industrialized world, and therefore a better understanding of the pathophysiological mechanisms underlying tissue fibrosis is sorely needed. We aimed to identify novel modifiers of tissue fibrosis expressed by myofibroblasts and their progenitors in their disease microenvironment through RNA silencing in vivo. We leveraged novel biology, targeting genes upregulated during liver and kidney fibrosis in this cell lineage, and employed small interfering RNA (siRNA)-formulated lipid nanoparticles technology to silence these genes in carbon-tetrachloride-induced liver fibrosis in mice. We identified five genes, Egr2, Atp1a2, Fkbp10, Fstl1, and Has2, which modified fibrogenesis based on their silencing, resulting in reduced Col1a1 mRNA levels and collagen accumulation in the liver. These genes fell into different groups based on the effects of their silencing on a transcriptional mini-array and histological outcomes. Silencing of Egr2 had the broadest effects in vivo and also reduced fibrogenic gene expression in a human fibroblast cell line. Prior to our study, Egr2, Atp1a2, and Fkbp10 had not been functionally validated in fibrosis in vivo. Thus, our results provide a major advance over the existing knowledge of fibrogenic pathways. Our study is the first example of a targeted siRNA assay to identify novel fibrosis modifiers in vivo.

Abstract Background Asthma is a heterogeneous chronic inflammatory disease of the airway, involving reversible airflow limitation and airway remodeling. T helper 17 (Th17) cells play an important role in the pathogenesis of allergic asthma. However, there is limited understanding of the signaling pathways controlling Th17 cell differentiation in asthma. The aim of this study was to investigate if the Yes-associated protein (YAP)/hypoxia inducible factor-1α (HIF-1α)/microRNA-182 (miR-182)/early growth response 2 (EGR2) axis is involved in mediating Th17 cell differentiation and disease severity in asthma. Methods The study included 29 pediatric patients with asthma, 22 healthy volunteers, ovalbumin-induced murine asthma models, and mouse naive CD4+ T cells. The subpopulation of Th17 cells was examined by flow cytometry. The levels of interleukin-17A were determined by enzyme linked immunosorbent assay. Chromatin immunoprecipitation-quantitative polymerase chain reaction assays and dual-luciferase reporter gene assays were performed to examine interactions between HIF-1α and miR-182, and between miR-182 and EGR2. Results YAP, HIF-1α, and miR-182 were upregulated but EGR2 was downregulated in human and mouse peripheral blood mononuclear cells from the asthma group. Abundant expression of YAP and HIF-1α promoted miR-182 expression and then inhibited EGR2, a target of miR-182, thus enhancing Th17 differentiation and deteriorating asthma and lipid metabolism dysfunction. In addition, in vivo overexpression of EGR2 countered the promoting effect of the YAP/HIF-1α/miR-182 axis on asthma and lipid metabolism dysfunction. Conclusion These results indicate that activation of the YAP/HIF-1α/miR-182/EGR2 axis may promote Th17 cell differentiation, exacerbate asthma development, and aggravate lipid metabolism dysfunction, thus suggesting a potential therapeutic target for asthma.

Previous studies have reported that deletion of the transcription factor, early growth response protein 2 (EGR2), in normal C57BL/6 (B6) resulted in the development of lupus-like autoimmune disease. However, increased EGR2 expression has been noted in human and murine lupus, which challenges the notion of the autoimmune suppressive role of EGR2 in B6 mice. In this study, we derived both conditional EGR2-/-B6/ lpr and EGR2-/-B6 mice to elucidate the immune and autoimmune regulatory roles of EGR2 in autoinflammation (B6/lpr) versus physiologically normal (B6) conditions. We found that conditional EGR2 deletion increased spleen weight, enhanced T cell activation and IFNγ production, and promoted germinal center B cells and LAG3+ regulatory T cells development in both B6/lpr and B6 mice. Nevertheless, EGR2 deletion also showed strikingly differential effects in these two strains on T lymphocyte subsets profile, Foxp3+ Tregs and plasma cell differentiation, anti-dsDNA autoantibodies and immunoglobulins production, and on the induction of IL-17 in in vitro activated splenocytes. Specifically, EGR2 deletion in B6/lpr mice significantly decreased serum levels of anti-dsDNA autoantibodies, total IgG, IgM, IgG1, and IgG2a with reduced plasma cells differentiation. Furthermore, EGR2 deletion in B6/lpr mice had no obvious effect on IgG immunocomplex deposition, medium caliber vessel, and glomeruli inflammation but increased complement C3 immunocomplex deposition and large caliber vessel inflammation in the kidneys. Importantly, we demonstrated that EGR2 deletion in B6/lpr mice significantly reduced pathogenic CD4-CD8-CD3+B220+ double negative T cells, which correlated with the reduced anti-dsDNA autoantibodies in serum and decreased IL-17 production in splenocytes of EGR2-/-B6/lpr mice. Together, our data strongly suggest that the role of EGR2 is complex. The immunoregulatory role of EGR2 varies at normal or autoinflammation conditions and should not be generalized in differential experimental settings. [ABSTRACT FROM AUTHOR]

Previous studies have reported that deletion of the transcription factor, early growth response protein 2 (EGR2), in normal C57BL/6 (B6) resulted in the development of lupus-like autoimmune disease. However, increased EGR2 expression has been noted in human and murine lupus, which challenges the notion of the autoimmune suppressive role of EGR2 in B6 mice. In this study, we derived both conditional EGR2-/-B6/lpr and EGR2-/-B6 mice to elucidate the immune and autoimmune regulatory roles of EGR2 in autoinflammation (B6/lpr) versus physiologically normal (B6) conditions. We found that conditional EGR2 deletion increased spleen weight, enhanced T cell activation and IFNγ production, and promoted germinal center B cells and LAG3+ regulatory T cells development in both B6/lpr and B6 mice. Nevertheless, EGR2 deletion also showed strikingly differential effects in these two strains on T lymphocyte subsets profile, Foxp3+ Tregs and plasma cell differentiation, anti-dsDNA autoantibodies and immunoglobulins production, and on the induction of IL-17 in in vitro activated splenocytes. Specifically, EGR2 deletion in B6/lpr mice significantly decreased serum levels of anti-dsDNA autoantibodies, total IgG, IgM, IgG1, and IgG2a with reduced plasma cells differentiation. Furthermore, EGR2 deletion in B6/lpr mice had no obvious effect on IgG immunocomplex deposition, medium caliber vessel, and glomeruli inflammation but increased complement C3 immunocomplex deposition and large caliber vessel inflammation in the kidneys. Importantly, we demonstrated that EGR2 deletion in B6/lpr mice significantly reduced pathogenic CD4-CD8-CD3+B220+ double negative T cells, which correlated with the reduced anti-dsDNA autoantibodies in serum and decreased IL-17 production in splenocytes of EGR2-/-B6/lpr mice. Together, our data strongly suggest that the role of EGR2 is complex. The immunoregulatory role of EGR2 varies at normal or autoinflammation conditions and should not be generalized in differential experimental settings.

Abstract Background Recent studies have shown that early growth response 2 (EGR2) is highly induced in activated T cells and regulates T cell functions. In normal C57BL/6 (B6) mice, deletion of EGR2 in lymphocytes results in the development of lupus-like systemic autoimmune disease, which implies indirectly an autoimmune protective role of EGR2. Conversely, increased EGR2 gene expression is suggested to link with high risk of human lupus. In the present studies we sought to clarify the expression and inflammation regulatory role of EGR2 in murine lupus T cells directly. Results We performed RT-qPCR analysis and found a significant increase of EGR2 mRNA expression in human lupus PBMCs and in CD4+ T cells from three different murine lupus models including MRL-lpr, B6-lpr, and B6.sle123 mice at diseased stage when compared to age-matched control MRL or B6 mice. By performing intracellular flow cytometry analysis, we found that EGR2 protein expression was significantly increased in resting lupus (either MRL-lpr or B6.sle123) CD4+ T cells when compared to CD4+ T cells from their respective non-autoimmune controls. However, there was no difference of EGR2 protein expression in anti-CD3 and anti-CD28 stimulated control and lupus CD4+ T cells since there was a stronger induction of EGR2 in activated control CD4+ T cells. EGR2 expression was significantly increased in MRL-lpr mice at an age when lupus is manifested. To understand further the function of elevated EGR2 in lupus CD4+ T cells, we inhibited EGR2 with a specific siRNA in vitro in splenocytes from MRL-lpr and control MRL mice at 15 weeks-of-age. We found that EGR2 inhibition significantly reduced IFNγ production in PMA and ionomycin activated MRL-lpr lupus CD4+ T cells, but not control MRL CD4+ T cells. We also found that inhibition of EGR2 in vitro suppressed the Th1 differentiation in both MRL and MRL-lpr naïve CD4+ T cells. Conclusions EGR2 is highly upregulated in human and murine lupus cells. Our in vitro data suggest a positive role of EGR2 in the regulation of Th1 differentiation and IFNγ production in lupus effector CD4+ T cells.

Chronic kidney disease (CKD) is a serious health problem worldwide, which ultimately leads to end-stage renal disease (ESRD). Renal fibrosis is the common pathway and major pathological manifestation for various CKD proceeding to ESRD. However, the underlying mechanisms and effective therapies are still ambiguous. Early growth response 2 (EGR2) is reportedly involved in organ formation and cell differentiation. To determine the role of EGR2 in renal fibrosis, we respectively confirmed the increased expression of EGR2 in kidney specimens from both CKD patients and mice with location in proximal tubules. Genetic deletion of EGR2 attenuated obstructive nephropathy while EGR2 overexpression further promoted renal fibrosis in mice subjected to unilateral ureteral obstruction (UUO) due to extracellular matrix (ECM) deposition mediating by partial epithelial-mesenchymal transition (EMT) as well as imbalance between matrix metalloproteinases (MMPs) and tissue inhibitor of MMPs (TIMPs). We found that EGR2 played a critical role in Smad3 phosphorylation, and inhibition of EGR2 reduced partial EMT leading to blockade of ECM accumulation in cultured human kidney 2 cells (HK2) treated with transforming growth factor β1 (TGF-β1). In addition, the transcription co-stimulator signal transducer and activator of transcription 3 (STAT3) phosphorylation was confirmed to regulate the transcription level of EGR2 in TGF-β1-induced HK2 cells. In conclusion, this study demonstrated that EGR2 played a pathogenic role in renal fibrosis by a p-STAT3-EGR2-p-Smad3 axis. Thus, targeting EGR2 could be a promising strategy for CKD treatment., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

BackgroundCannabidiol (CBD), the main non-psychoactive cannabinoid, has been previously shown by us to ameliorate clinical symptoms and to decrease inflammation in myelin oligodendrocyte glycoprotein (MOG)35-55-induced mouse experimental autoimmune encephalomyelitis model of multiple sclerosis as well as to decrease MOG35-55-induced T cell proliferation and IL-17 secretion. However, the mechanisms of CBD anti-inflammatory activities are unclear.MethodsHere we analyzed the effects of CBD on splenocytes (source of accessory T cells and antigen presenting cells (APC)) co-cultured with MOG35-55-specific T cells (TMOG) and stimulated with MOG35-55. Using flow cytometry, we evaluated the expression of surface activation markers and inhibitory molecules on T cells and B cells. TMOG cells were purified using CD4 positive microbead selection and submitted for quantitative PCR and microarray of mRNA transcript analyzes. Cell signaling studies in purified TMOG were carried out using immunoblotting.ResultsWe found that CBD leads to upregulation of CD69 and lymphocyte-activation gene 3 (LAG3) regulatory molecules on CD4(+)CD25(-) accessory T cells. This subtype of CD4(+)CD25(-)CD69(+)LAG3(+) T cells has been recognized as induced regulatory phenotype promoting anergy in activated T cells. Indeed, we observed that CBD treatment results in upregulation of EGR2 (a key T cell anergy inducer) mRNA transcription in stimulated TMOG cells. This was accompanied by elevated levels of anergy promoting genes such as IL-10 (anti-inflammatory cytokine), STAT5 (regulatory factor), and LAG3 mRNAs, as well as of several enhancers of cell cycle arrest (such as Nfatc1, Casp4, Cdkn1a, and Icos). Moreover, CBD exposure leads to a decrease in STAT3 and to an increase in STAT5 phosphorylation in TMOG cells, positive and negative regulators of Th17 activity, respectively. In parallel, we observed decreased levels of major histocompatibility complex class II (MHCII), CD25, and CD69 on CD19(+) B cells following CBD treatment, showing diminished antigen presenting capabilities of B cells and reduction in their pro-inflammatory functions.ConclusionsOur data suggests that CBD exerts its immunoregulatory effects via induction of CD4(+)CD25(-)CD69(+)LAG3(+) cells in MOG35-55-activated APC/TMOG co-cultures. This is accompanied by EGR2-dependent anergy of stimulated TMOG cells as well as a switch in their intracellular STAT3/STAT5 activation balance leading to the previously observed decrease in Th17 activity.

Gastric cancer is one of the most common malignancies harmful to human health. The search for effective drugs or gene therapy has aroused the attention of scientists. So far, microRNAs, as small non-coding RNAs, have the potential to be therapeutic targets for cancer. Herein, we found a highly expressed miR-25 in gastric cancer cell. However, the function of miR-25 for gastric cancer cell growth and apoptosis was unknown. Functionally, we used RT-qPCR, western blot, CCK-8, and flow cytometry to detect gastric cancer cell growth and apoptosis. The results indicated that miR-25 promoted gastric cancer cell growth and inhibited their apoptosis. Mechanistically, we found that a gene EGR2 was a potential target gene of miR-25. Further dual-luciferase results supported this prediction. Moreover, knockdown of EGR2 promoted gastric cancer cell growth and inhibited their apoptosis by flow cytometry detection. Altogether, these findings revealed miR-25 as a regulator of gastric cancer cell growth and apoptosis through targeting EGR2.

Gastric cancer is one of the most common malignancies harmful to human health. The search for effective drugs or gene therapy has aroused the attention of scientists. So far, microRNAs, as small non-coding RNAs, have the potential to be therapeutic targets for cancer. Herein, we found a highly expressed miR-25 in gastric cancer cell. However, the function of miR-25 for gastric cancer cell growth and apoptosis was unknown. Functionally, we used RT-qPCR, western blot, CCK-8, and flow cytometry to detect gastric cancer cell growth and apoptosis. The results indicated that miR-25 promoted gastric cancer cell growth and inhibited their apoptosis. Mechanistically, we found that a gene EGR2 was a potential target gene of miR-25. Further dual-luciferase results supported this prediction. Moreover, knockdown of EGR2 promoted gastric cancer cell growth and inhibited their apoptosis by flow cytometry detection. Altogether, these findings revealed miR-25 as a regulator of gastric cancer cell growth and apoptosis through targeting EGR2. [ABSTRACT FROM AUTHOR]

Background: Asthma is a heterogeneous chronic inflammatory disease of the airway, involving reversible airflow limitation and airway remodeling. T helper 17 (Th17) cells play an important role in the pathogenesis of allergic asthma. However, there is limited understanding of the signaling pathways controlling Th17 cell differentiation in asthma. The aim of this study was to investigate if the Yes-associated protein (YAP)/hypoxia inducible factor-1α (HIF-1α)/microRNA-182 (miR-182)/early growth response 2 (EGR2) axis is involved in mediating Th17 cell differentiation and disease severity in asthma. Methods: The study included 29 pediatric patients with asthma, 22 healthy volunteers, ovalbumin-induced murine asthma models, and mouse naive CD4+ T cells. The subpopulation of Th17 cells was examined by flow cytometry. The levels of interleukin-17A were determined by enzyme linked immunosorbent assay. Chromatin immunoprecipitation-quantitative polymerase chain reaction assays and dual-luciferase reporter gene assays were performed to examine interactions between HIF-1α and miR-182, and between miR-182 and EGR2. Results: YAP, HIF-1α, and miR-182 were upregulated but EGR2 was downregulated in human and mouse peripheral blood mononuclear cells from the asthma group. Abundant expression of YAP and HIF-1α promoted miR-182 expression and then inhibited EGR2, a target of miR-182, thus enhancing Th17 differentiation and deteriorating asthma and lipid metabolism dysfunction. In addition, in vivo overexpression of EGR2 countered the promoting effect of the YAP/HIF-1α/miR-182 axis on asthma and lipid metabolism dysfunction. Conclusion: These results indicate that activation of the YAP/HIF-1α/miR-182/EGR2 axis may promote Th17 cell differentiation, exacerbate asthma development, and aggravate lipid metabolism dysfunction, thus suggesting a potential therapeutic target for asthma. [ABSTRACT FROM AUTHOR]

Background: Bladder cancer is a prevalent malignancy with significant clinical implications. Small Ubiquitin-like Modifier (SUMO) pathway related genes (SPRG) have been implicated in the development and progression of cancer. Methods: In this study, we conducted a comprehensive analysis of SPRG in bladder cancer. We analyzed gene expression and prognostic value of SPRG and developed a SPRG signature (SPRGS) prognostic model based on four genes (HDAC4, TRIM27, EGR2, and UBE2I) in bladder cancer. Furthermore, we investigated the relationship between SPRGS and genomic alterations, tumor microenvironment, chemotherapy response, and immunotherapy. Additionally, we identified EGR2 as a key SPRG in bladder cancer. The expression of EGR2 in bladder cancer was detected by immunohistochemistry, and the cell function experiment clarified the effect of knocking down EGR2 on the proliferation, invasion, and migration of bladder cancer cells. Results: Our findings suggest that SPRGS hold promise as prognostic markers and predictive biomarkers for chemotherapy response and immunotherapy efficacy in bladder cancer. The SPRGS prognostic model exhibited high predictive accuracy for bladder cancer patient survival. We also observed correlations between SPRG and genomic alterations, tumor microenvironment, and response to chemotherapy. Immunohistochemical results showed that EGR2 was highly expressed in bladder cancer tissues, and its overexpression was associated with poor prognosis. Knockdown of EGR2 inhibited bladder cancer cell proliferation, invasion, and migration. Conclusion: This study provides valuable insights into the landscape of SPRGS in bladder cancer and their potential implications for personalized treatment strategies. The identification of EGR2 as a key SPRG and its functional impact on bladder cancer cells further highlights its significance in bladder cancer development and progression. Overall, SPRGS may serve as important prognostic markers and predictive biomarkers for bladder cancer patients, guiding treatment decisions and improving patient outcomes., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background and purpose: Mutations in the early growth response 2 gene (EGR2) cause demyelinating, but also axonal, neuropathies differing in severity and age of onset. Except for one family, all reported cases have autosomal dominant inheritance and mutations are localized within the three zinc finger (ZNF) DNA‐binding domain. The aim of this study was to provide a clinical and molecular analysis of a novel recessive mutation in EGR2. Methods: Clinical and electrophysiological assessments of three affected patients, from a consanguineous family, were performed. Genetic analyses of EGR2 were carried out by Sanger sequencing. Functional effects of clinical recessive mutations were assessed using a mammalian two‐hybrid assay. Results: A novel missense mutation (c.791C>T; p.P264L) in the homozygous state was detected outside the ZNF domains of the EGR2 gene. Three affected siblings presented with distal demyelinating polyneuropathy with severe sensory loss, progressive thoracolumbar scoliosis and trigeminal neuralgia. Respiratory compromise and cranial nerve dysfunction were also found. Our data indicate that the p.P264L mutation prevents interaction of EGR2 transcription factor with NAB corepressors, suggesting that a disruption of the NAB‐EGR2 protein interactions can result in dramatic neuropathy. Conclusion: Mutations in, or next to, the R1 domain of EGR2 should be considered with extreme caution for genetic counseling, since these could cause a severe neuropathy with an autosomal recessive manner of transmission. [ABSTRACT FROM AUTHOR]

Background/aims: Hirschsprung's disease (HSCR) is the most common digestive disease caused by disorders of neural crest development. Despite the known involvement of miR-140-5p in many human diseases, its biological role in Hirschsprung's disease (HSCR) remains undefined. In this study, we sought to reveal the roles of miR-140-5p in the pathogenesis of HSCR. Methods: Quantitative real-time PCR and western blotting were used to measure the relative expression levels of miRNAs, mRNAs, and proteins in stenotic and dilated sections of the colon of 32 HSCR patients. Targets and proteins were evaluated by western blotting, and Transwell, CCK-8, and flow cytometry assays were adopted to detect the functional effects of miR-140-5p on SH-SY5Y cells. Results: miR-140-5p was significantly downregulated in HSCR tissue samples with increased expression of EGR2, and knockdown of miR-140-5p inhibited cell migration and proliferation and promoted apoptosis in SH-SY5Y cell lines. EGR2 expression was inversely correlated with that of miR-140-5p in cell lines. Conclusions: miR-140-5p may influence the pathogenesis of HSCR by targeting EGR2. [ABSTRACT FROM AUTHOR]

Background: Recent studies have shown that early growth response 2 (EGR2) is highly induced in activated T cells and regulates T cell functions. In normal C57BL/6 (B6) mice, deletion of EGR2 in lymphocytes results in the development of lupus-like systemic autoimmune disease, which implies indirectly an autoimmune protective role of EGR2. Conversely, increased EGR2 gene expression is suggested to link with high risk of human lupus. In the present studies we sought to clarify the expression and inflammation regulatory role of EGR2 in murine lupus T cells directly. Results: We performed RT-qPCR analysis and found a significant increase of EGR2 mRNA expression in human lupus PBMCs and in CD4+ T cells from three different murine lupus models including MRL-lpr, B6-lpr, and B6.sle123 mice at diseased stage when compared to age-matched control MRL or B6 mice. By performing intracellular flow cytometry analysis, we found that EGR2 protein expression was significantly increased in resting lupus (either MRL-lpr or B6.sle123) CD4+ T cells when compared to CD4+ T cells from their respective non-autoimmune controls. However, there was no difference of EGR2 protein expression in anti-CD3 and anti-CD28 stimulated control and lupus CD4+ T cells since there was a stronger induction of EGR2 in activated control CD4+ T cells. EGR2 expression was significantly increased in MRL-lpr mice at an age when lupus is manifested. To understand further the function of elevated EGR2 in lupus CD4+ T cells, we inhibited EGR2 with a specific siRNA in vitro in splenocytes from MRL-lpr and control MRL mice at 15 weeks-of-age. We found that EGR2 inhibition significantly reduced IFNγ production in PMA and ionomycin activated MRL-lpr lupus CD4+ T cells, but not control MRL CD4+ T cells. We also found that inhibition of EGR2 in vitro suppressed the Th1 differentiation in both MRL and MRL-lpr naïve CD4+ T cells. Conclusions: EGR2 is highly upregulated in human and murine lupus cells. Our in vitro data suggest a positive role of EGR2 in the regulation of Th1 differentiation and IFNγ production in lupus effector CD4+ T cells. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Various microRNAs (miRNAs) have been reported to be involved in the pathogenesis and development of human cancers, including papillary thyroid carcinoma (PTC). However, the role of miR-224-5p in PTC progression remains unclear. Therefore, the purpose of this study is to illuminate the function of miR-224-5p in PTC. PATIENTS AND METHODS: Expression of miR-224-5p and EGR2 was examined in PTC by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Transwell assay was used to detect cell migration and invasion. Western blot analysis was used to detect epithelial-mesenchymal transition (EMT). The relationship between miR-224-5p and EGR2 was confirmed by Dual-Luciferase assay. RESULTS: Upregulation of miR-224-5p and downregulation of EGR2 expression were detected in PTC tissues and cells. Upregulation of miR-224-5p was found to be associated with TNM stage and lymph node metastasis. Meanwhile, it also predicted poor prognosis in PTC patients. Functionally, upregulation of miR-224- 5p promoted cell metastasis and EMT in PTC. In addition, miR-224-5p was detected to directly target EGR2. EGR2 expression was negatively correlated with EGR2 expression in PTC. Of note, overexpression of EGR2 attenuated the carcinogenic effects of miR-224-5p in PTC. CONCLUSIONS: MiR-224-5p promotes cell migration, invasion, and EMT in PTC by targeting EGR2. [ABSTRACT FROM AUTHOR]

Precise regulation of Egr2 transcription is fundamentally important to the control of peripheral myelination. Here, we describe a long non-coding RNA antisense to the promoter of Egr2 (Egr2-AS-RNA). During peripheral nerve injury, the expression of Egr2-AS-RNA is increased and correlates with decreased Egr2 transcript and protein levels. Ectopic expression of Egr2-AS-RNA in dorsal root ganglion (DRG) cultures inhibits the expression of Egr2 mRNA and induces demyelination. In vivo inhibition of Egr2-AS-RNA using oligonucleotide GapMers released from a biodegradable hydrogel following sciatic nerve injury reverts the EGR2-mediated gene expression profile and significantly delays demyelination. Egr2-AS-RNA gradually recruits H3K27ME3, AGO1, AGO2, and EZH2 on the Egr2 promoter following sciatic nerve injury. Furthermore, expression of Egr2-AS-RNA is regulated through ERK1/2 signaling to YY1, while loss of Ser184 of YY1 regulates binding to Egr2-AS-RNA. In conclusion, we describe functional exploration of an antisense long non-coding RNA in peripheral nervous system (PNS) biology.

The development of CD1d-restricted invariant natural killer T (iNKT) cells, a population that is critical for both innate and adaptive immunity, is regulated by multiple transcription factors, but the molecular mechanisms underlying how the transcriptional activation of these factors are regulated during iNKT development remain largely unknown. We found that the histone acetyltransferase general control non-derepressible 5 (GCN5) is essential for iNKT cell development during the maturation stage. GCN5 deficiency blocked iNKT cell development in a cell-intrinsic manner. At the molecular level, GCN5 is a specific lysine acetyltransferase of early growth responsive gene 2 (EGR2), a transcription factor required for iNKT cell development. GCN5-mediated acetylation positively regulated EGR2 transcriptional activity, and both genetic and pharmacological GCN5 suppression specifically inhibited the transcription of EGR2 target genes in iNKT cells, including Runx1, promyelocytic leukemia zinc finger protein (PLZF), interleukin (IL)-2Rb, and T-bet. Therefore, our study revealed GCN5-mediated EGR2 acetylation as a molecular mechanism that regulates iNKT development.

Abstract Background Secreted frizzled-related protein 1 (SFRP1) expression is down-regulated in a multitude of cancers, including breast cancer. Loss of Sfrp1 also exacerbates weight gain as well as inflammation. Additionally, loss of SFRP1 enhances TGF-β signaling and the downstream MAPK pathway. TGF-β has been shown to increase the expression of Early Growth Response 2 (EGR2), a transcription factor implicated in immune function in a wide variety of cell types. The work described here was initiated to determine whether SFRP1 modulation affects TGF-β mediated EGR2 expression in mammary tissues as well as macrophage polarization. Methods Real-time PCR analysis was performed to examine EGR2 expression in human and murine mammary epithelial cells and tissues in response to SFRP1 modulation. Chemical inhibition was employed to investigate the roles TGF-β and MAPK signaling play in the control of EGR2 expression in response to SFRP1 loss. Primary murine macrophages were isolated from Sfrp1−/− mice and stimulated to become either M1 or M2 macrophages, treated with recombinant SFRP1, and real-time PCR was used to measure the expression of murine specific M1/M2 markers [Egr2 (M2) and Gpr18 (M1)]. Immunohistochemical analysis was used to measure the expression of human specific M1/M2 markers [CD163 (M2) and HLA-DRA (M2)] in response to rSFRP1 treatment in human mammary explant tissue. Results Knockdown of SFRP1 expression increases the expression of EGR2 mRNA in human mammary epithelial cells and addition of rSFRP1 decreases the expression of EGR2 when added to explant mammary gland tissues. Chemical inhibition of both TGF-β and MAPK signaling in Sfrp1−/− or knockdown mammary epithelial cells results in decreased expression of EGR2. Stimulated murine macrophages obtained from Sfrp1−/− mice and treated with rSFRP1 exhibit a reduction in Egr2 expression and an increase in Gpr18 mRNA expression. Human mammary explant tissue treated with rSFRP1 decreases CD163 protein expression whereas there was no effect on the expression of HLA-DRA. Conclusions Loss of SFRP1 likely contributes to tumor progression by altering the expression of a critical transcription factor in both the epithelium and the immune system.

Fibrotic diseases contribute to 45% of deaths in the industrialized world, and therefore a better understanding of the pathophysiological mechanisms underlying tissue fibrosis is sorely needed. We aimed to identify novel modifiers of tissue fibrosis expressed by myofibroblasts and their progenitors in their disease microenvironment through RNA silencing in vivo. We leveraged novel biology, targeting genes upregulated during liver and kidney fibrosis in this cell lineage, and employed small interfering RNA (siRNA)-formulated lipid nanoparticles technology to silence these genes in carbon-tetrachloride-induced liver fibrosis in mice. We identified five genes, Egr2, Atp1a2, Fkbp10, Fstl1, and Has2, which modified fibrogenesis based on their silencing, resulting in reduced Col1a1 mRNA levels and collagen accumulation in the liver. These genes fell into different groups based on the effects of their silencing on a transcriptional mini-array and histological outcomes. Silencing of Egr2 had the broadest effects in vivo and also reduced fibrogenic gene expression in a human fibroblast cell line. Prior to our study, Egr2, Atp1a2, and Fkbp10 had not been functionally validated in fibrosis in vivo. Thus, our results provide a major advance over the existing knowledge of fibrogenic pathways. Our study is the first example of a targeted siRNA assay to identify novel fibrosis modifiers in vivo.

Tendon cells exist in a dense extracellular matrix and mechanical loading is important for the strength development of this matrix. We therefore use a three‐dimensional (3D) culture system for tendon formation in vitro. The objectives of this study were to elucidate the temporal expression of tendon‐related genes during the formation of artificial tendons in vitro and to investigate if early growth response‐1 (EGR1), EGR2, FOS, and cyclooxygenase‐1 and ‐2 (PTGS1 and PTGS2) are sensitive to mechanical loading. First, we studied messenger RNA (mRNA) levels of several tendon‐related genes during formation of tendon constructs. Second, we studied the mRNA levels of, for example, EGR1 and EGR2 after different degrees of loading; dynamic physiologic‐range loading (2.5% strain), dynamic overloading (approximately 10% strain), or tension release. The gene expression for tendon‐related genes (i.e., EGR2, MKX, TNMD, COL3A1) increased with time after seeding into this 3D model. EGR1, EGR2, FOS, PTGS1, and PTGS2 did not respond to physiologic‐range loading. But overloading (and tension release) lead to elevated levels of EGR1 and EGR2 (p ≤ 0.006). FOS and PTGS2 were increased after overloading (both p < 0.007) but not after tension release (p = 0.06 and 0.08). In conclusion, the expression of tendon‐related genes increases during the formation of artificial tendons in vitro, including EGR2. Furthermore, the gene expression of EGR1 and EGR2 in human tendon cells appear to be sensitive to overloading and unloading but did not respond to the single episode of physiologic‐range loading. These findings could be helpful for the understanding of tendon tensional homeostasis. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:173–181, 2020 [ABSTRACT FROM AUTHOR]

OBJECTIVE: Long non-coding RNA (LncRNA) has been reported to play an important role in type 2 diabetes (T2D). We investigated the role of LncRNA maternally expressed gene 3 (MEG3) and its potential interaction with miR-185-5p in palmitate- induced hepatocyte insulin resistance. PATIENTS AND METHODS: High-fat diet (HFD) mice and insulin resistant hepatocyte were employed. Relative mRNA expressions of MEG3, miR-185-5p, and early growth response proteins-2 (Egr2) were measured by qRT-PCR. Western blot was performed to evaluate Egr2 protein expression levels. Glycogen contents and plasma insulin levels were tested by the corresponding assay. RESULTS: MEG3 and Egr2 were upregulated, but miR-185-5p was downregulated in palmitate- treated insulin resistance hepatocytes and HFD mice. MEG3 knockdown alleviated the influence of palmitate on insulin resistance in vitro and in vivo. miR-185-5p expression was upregulated upon MEG3 knockdown. Expression of Egr2 was positively correlated with MEG3 knockdown or overexpression, which could be negatively managed by abnormal expression of miR-185-5p. CONCLUSIONS: Our data demonstrated that LncRNA MEG3 aggravated palmitate-induced insulin resistance by regulating miR-185-5p/Egr2 axis, providing new insights into T2D therapeutic strategies. [ABSTRACT FROM AUTHOR]

• LAG3 upregulation inhibits effector function of CD4 T -cells from PCa. • Insufficiency expression of ATM upregulates LAG3 expression in PCa. • ATM dysfunction impairs AMPKα which enhances the binding of EGR2 and XBP1 to LAG3 promoters. • Blocking EGR2/XBP1 or restoring ATM-AMPKα aid in the cancer immunotherapy for PCa. Immunotherapy for prostate cancer (PCa) faces serious challenges. Therefore, the co-inhibitory receptors that regulate T cell function of PCa must be elucidated. Here we identified that the inhibitory receptor LAG3 was significantly induced in T cells from PCa patients. Gene array analysis revealed that insufficient ataxia telangiectasia mutated (ATM) gene expression in PCa T cells was responsible for the elevated LAG3 expression. Mechanistically, insufficient ATM expression impaired its ability to activate AMPKα signaling and CD4+ T cell functions, which further enhances the binding of the transcription factors XBP1 and EGR2 to LAG3 promoter. Reconstitution of ATM and inhibition of XBP1 or EGR2 in PCa T cells suppressed LAG3 expression and restored the effector function of CD4+ T cells from PCa. Our study revealed the mechanism of LAG3 upregulation in CD4+ T lymphocytes of PCa patients and may provide insights for the development of immunotherapeutic strategies for PCa treatment. [ABSTRACT FROM AUTHOR]

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic multisystem disease exhibiting a variety of symptoms and affecting multiple systems. Psychological stress and virus infection are important. Virus infection may trigger the onset, and psychological stress may reactivate latent viruses, for example, Epstein–Barr virus (EBV). It has recently been reported that EBV induced gene 2 (EBI2) was upregulated in blood in a subset of ME/CFS patients. The purpose of this study was to determine whether the pattern of expression of early growth response (EGR) genes, important in EBV infection and which have also been found to be upregulated in blood of ME/CFS patients, paralleled that of EBI2. EGR gene upregulation was found to be closely associated with that of EBI2 in ME/CFS, providing further evidence in support of ongoing EBV reactivation in a subset of ME/CFS patients. EGR1, EGR2, and EGR3 are part of the cellular immediate early gene response and are important in EBV transcription, reactivation, and B lymphocyte transformation. EGR1 is a regulator of immune function, and is important in vascular homeostasis, psychological stress, connective tissue disease, mitochondrial function, all of which are relevant to ME/CFS. EGR2 and EGR3 are negative regulators of T lymphocytes and are important in systemic autoimmunity.