关键词： USP22   AP2   ATF3   NSCLC   Transcriptional regulation   Cell proliferation   Invasion   Malignancy   PROMOTES   TUMORIGENESIS   METASTASIS   ACTIVATION   RESISTANCE   CARCINOMA   SURVIVAL   MARKER   SIRT1  

摘要： Background: Ubiquitin-specific protease 22 (USP22), a putative cancer stem cell marker, is frequently upregulated in cancers, and USP22 overexpression is associated with aggressive growth, metastasis, and therapy resistance in various human cancers including lung cancer. However, USP22 gene amplification seldom occurs, and the mechanism underlying USP22 upregulation in human cancers remains largely unknown. Methods: A luciferase reporter driven by a promoter region of USP22 gene was selectively constructed to screen against a customized siRNA library targeting 89 selected transcription factors to identify potential transcription factors (TFs) that regulate USP22 expression in human non-small cell lung cancers (NSCLC). Association of identified TFs with USP22 and potential role of the TFs were validated and explored in NSCLC by biological assays and immunohistochemistry analysis. Results: Luciferase reporter assays revealed that SP1 and activating transcription factor 3 (ATF3) inhibit USP22 transcription, while transcription factor AP-2 Alpha/Beta (TFAP2A/2B) and c-Myc promote USP22 transcription. Binding site-directed mutagenesis and chromosome immunoprecipitation (ChIP) assays validated AP2a and AP213 are novel TFs of USP22. Furthermore, overexpression of AP2A and AP2B significantly upregulates USP22 expression, and its target: Cyclin D1, concurrently enhances the proliferation, migration, and invasion of NSCLC A549 and H1299 cells in a partially USP22-dependent manner. Moreover, AP2 protein level correlated with USP22 protein in human NSCLC tissues. Conclusion: Our findings indicate AP2 alpha and AP2 beta are important transcription factors driving USP22 gene expression to promote the progression of NSCLC, and further support USP22 as a potential biomarker and therapeutic target for lung cancer.

关键词： EXPRESSION   CNS   NEURONS   GROWTH   ANNEXIN-A3   MICROGLIA   SYSTEM   MARKER   ATF3  

摘要： Robust axon regeneration of motoneurons (MNs) occurs in rodent models upon peripheral nerve injury (PNI). However, genome-wide dynamic molecules and permissive microenvironment following insult in MNs remain largely unknown. Here, we firstly tackled by high-coverage and massive sequencing of laserdissected individual ChAT+ cells to uncover molecules and pro-regenerative programs of MNs from injury to the regenerating phase after PNI. ``Injured'' populations at 1d similar to 7d were well distinguished and three response phases were well defined by elucidating with several clues (Gap43, etc). We found remarkable changes of genes expressed by injured motoneurons to activate and enhance intrinsic axon regrowth or crosstalkwith other cellular or non-cellular counterpart in the activated regenerative microenvironment, specifically microglia/macrophage. We also identified an injury and regeneration-associated module and critical regulators including core transcription factors (Atf3, Arid5a, Klf6, Klf7, Jun, Stat3, and Myc). This study provides a vital resource and critical molecules for studying neural repair of axotomized motoneurons.

关键词： ADAPTIVE-RESPONSE   TUMOR   CELLS   SUMOYLATION   CHOLESTEROL   MODULATION   REPRESSION   EXCHANGE   ANTIGEN   INNATE  

摘要： Effector trogocytosis between malignant cells and tumor-specific cytotoxic T lymphocytes (CTLs) contrib-utes to immune evasion through antigen loss on target cells and fratricide of antigen-experienced CTLs by other CTLs. The mechanisms regulating these events in tumors remain poorly understood. Here, we demon-strate that tumor-derived factors (TDFs) stimulated effector trogocytosis and restricted CTLs' tumoricidal ac-tivity and viability in vitro. TDFs robustly altered the CTL's lipid profile, including depletion of 25-hydroxycholesterol (25HC). 25HC inhibited trogocytosis and prevented CTL's inactivation and fratricide. Mechanistically, TDFs induced ATF3 transcription factor that suppressed the expression of 25HC-regulating gene-cholesterol 25-hydroxylase (CH25H). Stimulation of trogocytosis in the intratumoral CTL by the ATF3-CH25H axis attenuated anti-tumor immunity, stimulated tumor growth, and impeded the efficacy of chimeric antigen receptor (CAR) T cell adoptive therapy. Through use of armored CAR constructs or pharmacologic agents restoring CH25H expression, we reversed these phenotypes and increased the efficacy of immuno-therapies.

关键词： Myocardial ischemia   reperfusion   ATF3   Ferroptosis   FANCD2   ACTIVATING TRANSCRIPTION FACTOR-3   ACUTE MYOCARDIAL-INFARCTION   STRESS-INDUCIBLE GENE   MECHANICAL COMPLICATIONS   CELL-DEATH   EXPRESSION   INJURY   PROTECTS   FAILURE   BIOLOGY  

摘要： Introduction: Ferroptosis, a newly identified type of programmed cell death type, has been proven to contribute to the progression of myocardial ischemia/reperfusion (I/R) injury. However, little is known about ferroptosis regulation in I/R ***: We identified activating transcription factor 3 (ATF3) as a vital regulator of I/R induced ferroptosis and investigated the effects and potential mechanism of ATF3 in cardiac ***: In this study, the dynamic RNA-sequencing (RNA-seq) analysis were performed on mouse hearts exposed to different I/R schedules to identify that ATF3 represents an important modulatory molecule in myocardial I/R injury. Then knockout, rescue and overexpression methods were used in mice and neonatal mouse cells (NMCs) to illustrate the effect of ATF3 on myocardial I/R injury. Loss/gain of function techniques were used both in vivo and in vitro to explore the effects of ATF3 on ferroptosis in I/R injury. Furthermore, chromatin immunoprecipitation sequence (ChIP-seq) analysis was performed in the AC16 human cardiomyocyte cell line to investigate potential genes regulated by ***: ATF3 expression reached highest level at early stage of reperfusion, knockout of ATF3 significantly aggravated I/R injury, which could be rescued by ATF3 re-expression. Knockout and the re-expression of ATF3 changed the transcription levels of multiple ferroptosis genes. In addition, results showed that overexpression of ATF3 inhibits cardiomyocyte ferroptosis triggered by erastin and RSL3. Lastly, ChIP-seq and dual luciferase activity analysis revealed ATF3 could bind to the transcription start site of Fanconi anaemia complementation group D2 (FANCD2) and increased the FANCD2 promoter activity. Furthermore, we first demonstrated that overexpression of FANCD2 exerts significant anti-ferroptosis and cardioprotective effect on AC16 cell H/R ***: ATF3 inhibits cardiomyocyte ferroptotic death in I/R injury, which might be related

关键词： Nonalcoholic steatohepatitis (NASH)   Metabolic dysfunction-associated steatohepatitis (MASH)   Overnutrition   Type-2 diabetes mellites   Steatosis   High-fat diet   Fructose   Inflammation   Mitochondria   Mitochondrial dysregulation   Oxidative stress   Reactive oxygen species   Redox signalling   Endoplasmic reticulum stress   Apoptosis   Iron overload   Insulin resistance   Lipotoxicity   Fatty acid beta-oxidation   Nrf2   Glutathione   Thioredoxin   Detoxification   Autophagy   Keap1   beta-TrCP   Hrd1/SYVN1   JNK   p38(MAPK)   GSK-3   ATF3   Bach1   FOSL1/Fra1   TGF-beta   FATTY LIVER-DISEASE   ENDOPLASMIC-RETICULUM STRESS   UNFOLDED PROTEIN RESPONSE   NF-KAPPA-B   INDUCED OXIDATIVE STRESS   NUCLEAR FACTOR-E2-RELATED FACTOR-2   THIOREDOXIN-INTERACTING PROTEIN   ADIPOSE TRIGLYCERIDE LIPASE   SUBSTRATE ADAPTER PROTEIN   HEME OXYGENASE-1 GENE  

摘要： Non-alcoholic steatohepatitis (NASH) represents a global health concern. It is characterised by fatty liver, hepatocyte cell death and inflammation, which are associated with lipotoxicity, endoplasmic reticulum (ER) stress, mitochondrial dysfunction, iron overload and oxidative stress. NF-E2 p45-related factor 2 (Nrf2) is a transcription factor that combats oxidative stress. Remarkably, Nrf2 is downregulated during the development of NASH, which probably accelerates disease, whereas in pre-clinical studies the upregulation of Nrf2 inhibits NASH. We now review the scientific literature that proposes Nrf2 downregulation during NASH involves its increased ubiquitylation and proteasomal degradation, mediated by Kelch-like ECH-associated protein 1 (Keap1) and/or beta-transducin repeat-containing protein (beta-TrCP) and/or HMG-CoA reductase degradation protein 1 (Hrd1, also called synoviolin (SYVN1)). Additionally, downregulation of Nrf2-mediated transcription during NASH may involve diminished recruitment of coactivators by Nrf2, due to increased levels of activating transcription factor 3 (ATF3) and nuclear factor-kappaB (NF-kappa B) p65, or competition for promoter binding due to upregulation of BTB and CNC homology 1 (Bach1). Many processes that downregulate Nrf2 are triggered by transforming growth factor-beta (TGF-beta), with oxidative stress amplifying its signalling. Oxidative stress may also increase suppression of Nrf2 by beta-TrCP through facilitating formation of the DSGIS-containing phosphodegron in Nrf2 by glycogen synthase kinase-3. In animal models, knockout of Nrf2 increases susceptibility to NASH, while pharmacological activation of Nrf2 by inducing agents that target Keap1 inhibits development of NASH. These inducing agents probably counter Nrf2 downregulation affected by beta-TrCP, Hrd1/SYVN1, ATF3, NF-kappa B p65 and Bach1, by suppressing oxidative stress. Activation of Nrf2 is also likely to inhibit NASH by ameliorating lipotoxicity, inflammation, ER

关键词： ATF3   山羊   肌内前体脂肪细胞   过表达   诱导分化  

摘要： 本研究旨在探究山羊转录激活因子3(activating transcription factor 3,ATF3)对肌内前体脂肪细胞分化的影响,并从分子水平阐明其可能作用途径。利用基因重组方法构建pEGFP-N1-ATF3过表达重组质粒,脂质体转染肌内前体脂肪细胞,通过油红O脂肪染色法从细胞形态学水平确定对分化的影响,利用实时荧光定量PCR(qRT-PCR)技术检测脂肪细胞分化标记基因相对表达水平,从分子水平确定对分化的影响。最终成功构建pEGFP-N1-ATF3过表达载体,转染山羊肌内前体脂肪细胞后发现脂滴积聚被抑制,qRT-PCR检测到脂肪细胞分化标志基因PPARγ、C/EBPα、SREBP1极显著下调(P<0.01),C/EBPβ、AP2显著下调(P<0.05),通过ALGGEN PROMO程序预测PPARγ、C/EBPα和AP2的启动子区域存在ATF3结合位点。研究表明,过表达山羊ATF3抑制肌内前体脂肪细胞脂滴积聚,这种作用通过下调PPARγ、C/EBPα和AP2来实现,研究结果为阐明山羊ATF3调控肌内前体脂肪细胞分化机制提供重要的基础数据。

关键词： brown adipose tissue   Adipocytes   Proteasome   Ubiquitin   Proteostasis   PSMB4   ATF3   BROWN ADIPOSE-TISSUE   SUBUNIT   LIPODYSTROPHY   NRF1  

摘要： Objective: Regulation of proteasomal activity is an essential component of cellular proteostasis and function. This is evident in patients with mutations in proteasome subunits and associated regulators, who suffer from proteasome-associated autoinflammatory syndromes (PRAAS). These patients display lipodystrophy and fevers, which may be partly related to adipocyte malfunction and abnormal thermogenesis in adipose tissue. However, the cell-intrinsic pathways that could underlie these symptoms are unclear. Here, we investigate the impact of two proteasome subunits implicated in PRAAS, Psmb4 and Psmb8, on differentiation, function and proteostasis of brown adipocytes. Methods: In immortalized mouse brown pre-adipocytes, levels of Psmb4, Psmb8, and downstream effectors genes were downregulated through reverse transfection with siRNA. Adipocytes were differentiated and analyzed with various assays of adipogenesis, lipogenesis, lipolysis, inflammation, and respiration. Results: Loss of Psmb4, but not Psmb8, disrupted proteostasis and adipogenesis. Proteasome function was reduced upon Psmb4 loss, but partly recovered by the activation of Nuclear factor, erythroid-2, like-1 (Nfe2l1). In addition, cells displayed higher levels of surrogate inflammation and stress markers, including Activating transcription factor-3 (Atf3). Simultaneous silencing of Psmb4 and Atf3 lowered inflammation and restored adipogenesis. Conclusions: Our study shows that Psmb4 is required for adipocyte development and function in cultured adipocytes. These results imply that in humans with PSMB4 mutations, PRAAS-associated lipodystrophy is partly caused by disturbed adipogenesis. While we uncover a role for Nfe2l1 in the maintenance of proteostasis under these conditions, Atf3 is a key effector of inflammation and blocking adipogenesis. In conclusion, our work highlights how proteasome dysfunction is sensed and mitigated by the integrated stress response in adipocytes with potential relevance for PRAA

关键词： CIRCULAR RNA   CANCER PROGRESSION   BREAST-CANCER   CELL   GROWTH   GLIOMA   UPF1  

摘要： Glioblastoma multiforme (GBM) is the most lethal type of craniocerebral gliomas. Glioma stem cells (GSCs) are fundamental reasons for the malignancy and recurrence of GBM. Revealing the critical mechanism within GSCs' self-renewal ability is essential. Our study found a novel circular RNA (circRPPH1) that was up-regulated in GSCs and correlated with poor survival. The effect of circRPPH1 on the malignant phenotype and self-renewal of GSCs was detected in vitro and in vivo. Mechanistically, UPF1 can bind to circRPPH1 and maintain its stability. Therefore, more existing circRPPH1 can interact with transcription factor ATF3 to further transcribe UPF1 and Nestin expression. It formed a feedback loop to keep a stable stream for stemness biomarker Nestin to strengthen tumorigenesis of GSCs continually. Besides, ATF3 can activate the TGF-beta signaling to drive GSCs for tumorigenesis. Knocking down the expression of circRPPH1 significantly inhibited the proliferation and clonogenicity of GSCs both in vitro and in vivo. The overexpression of circRPPH1 enhanced the self-renewal of GSCs. Our findings suggest that UPF1/circRPPH1/ATF3 maintains the potential self-renewal of GSCs through interacting with RNA-binding protein and activating the TGF-beta signal pathway. Breaking the feedback loop against self-renewing GSCs may represent a novel therapeutic target in GBM treatment.

关键词： 三叉神经痛   眶下神经缩窄术   miR-30b   ATF3  

摘要： 目的探讨miR-30b在三叉神经痛(TN)模型大鼠三叉神经节(TG)中发挥的作用。方法采用眶下神经缩窄术(ION-CCI)构建大鼠TN模型。用Von Frey毛刷检测大鼠的机械痛阈。通过qRT-PCR及Western blot检测术侧TG内miR-30b和激活转录因子3(ATF3)表达变化。经眶下孔分别向ION-CCI大鼠的TG内定位注射miR-30b的类似物(agomir)和agomir的阴性对照(agomir NC),检测大鼠的机械痛阈及干预后ATF3表达的变化。结果ION-CCI组大鼠在术后第2~28天出现机械痛阈的降低(P<0.05)。ION-CCI组较假手术组(Sham组)术后TG中miR-30b表达降低,ATF3表达升高(P<0.05)。ION-CCI组过表达miR-30b后,大鼠机械痛阈升高,TG中ATF3表达降低(P<0.05)。结论miR-30b参与调控TN的发生、发展,miR-30b可能是TN潜在的治疗靶点。