关键词： ACTIVATING TRANSCRIPTION FACTOR-3   TO-LUMINAL DIFFERENTIATION   ADAPTIVE-RESPONSE   CANCER   ESTROGEN   BASAL   PTEN   GROWTH   BETA   INFLAMMATION  

摘要： Steroid sex hormones can induce prostate carcinogenesis, and are thought to contribute to the development of prostate cancer during aging. However, the mechanism for hormone-induced prostate carcinogenesis remains elusive. Here, we report that activating transcription factor 3 (ATF3)-a broad stress sensor-suppressed hormone-induced prostate carcinogenesis in mice. Although implantation of testosterone and estradiol (T+E-2) pellets for 2 months in wild-type mice rarely induced prostatic intraepithelial neoplasia (PIN) in dorsal prostates (one out of eight mice), the loss of ATF3 led to the appearance of not only PIN but also invasive lesions in almost all examined animals. The enhanced carcinogenic effects of hormones on ATF3-deficient prostates did not appear to be caused by a change in estrogen signaling, but were more likely a consequence of elevated androgen signaling that stimulated differentiation of prostatic basal cells into transformation-preferable luminal cells. Indeed, we found that hormone-induced lesions in ATF3-knockout mice often contained cells with both basal and luminal characteristics, such as p63(+) cells (a basal-cell marker) showing luminal-like morphology, or cells double-stained with basal (CK5(+)) and luminal (CK8(+)) markers. Consistent with these findings, low ATF3 expression was found to be a poor prognostic marker for prostate cancer in a cohort of 245 patients. Our results thus support that ATF3 is a tumor suppressor in prostate cancer.

关键词： Activating transcription factor-3   Berberine   Inflammation   Lipopolysaccharide   Macrophage   NITRIC-OXIDE SYNTHASE   PROTEIN-KINASE   RESPIRATORY-CHAIN   GENE-EXPRESSION   ADIPOSE-TISSUE   CELLS   MECHANISM   METFORMIN   ATF3   INHIBITION  

摘要： Berberine is an isoquinoline alkaloid found in Rhizoma coptidis, and elicits anti-inflammatory effects through diverse mechanisms. Based on previous reports that activating transcription factor-3 (ATF-3) acts as a negative regulator of LPS signaling, the authors investigated the possible involvement of ATF-3 in the anti-inflammatory effects of berberine. It was found berberine concentration-dependently induced the expressions of ATF-3 at the mRNA and protein levels and concomitantly suppressed the LPS-induced productions of proinflammatory cytokines (TNF-alpha, IL-6, and IL-1 beta). In addition, ATF-3 knockdown abolished the inhibitory effects of berberine on LPS-induced proinflammatory cytokine production, and prevented the berberine-induced suppression of MAPK phosphorylation, but had little effect on AMPK phosphorylation. On the other hand, the effects of berberine, that is, ATF-3 induction, proinflammatory cytokine inhibition, and MAPK inactivation, were prevented by AMPK knockdown, suggesting ATF-3 induction occurs downstream of AMPK activation. The in vivo administration of berberine to mice with LPS-induced endotoxemia increased ATF-3 expression and AMPK phosphorylation in spleen and lung tissues, and concomitantly reduced the plasma and tissue levels of proinflammatory cytokines. These results suggest berberine has an anti-inflammatory effect on macrophages and that this effect is attributable, at least in part, to pathways involving AMPK activation and ATF-3 induction.

关键词： glomerular mesangial cells   sublytic C5b-9   Thy-1 nephritis   transcription factor   acetylation   apoptosis  

摘要： The apoptosis of glomerular mesangial cells(GMCs)is considered to be an important contributor to the initiation and development of rat Thy-1 nephritis(Thy-1N)and is accompanied by sublytic C5b-9 ***,the mechanism by which sublytic C5b-9 triggers GMC apoptosis has not been *** this study,functional and histological examinations were performed on GMCs treated with sublytic C5b-9(in vitro)and renal tissues of Thy-1N rats(in vivo).The in vitro studies found that sublytic C5b-9 could trigger GMC apoptosis through upregulating Egr-1,ATF3,and Gadd45 ***-1-mediated post-transcriptional modulation of ATF3,Egr-1/ATF3-enhanced Gadd45 promoter activity,and p300-mediated ATF3 acetylation were all involved in GMC *** importantly,the effective binding elements for Egr-1 and ATF3 to Gadd45β/γpromoters and the ATF3 acetylation site were *** vivo,silencing renal p300,Egr-1,ATF3,and Gadd45β/γsignificantly decreased GMC apoptosis,secondary GMC proliferation,and urinary protein secretion in Thy-1N ***,these findings implicate that sublytic C5b-9-induced activation of Egr-1/p300–ATF3/Gadd45 axis plays a critical role in GMC apoptosis in Thy-1N rats.

关键词： 非小细胞肺癌   ATF3   免疫组化   RT-PCR  

摘要： 目的：初步探讨非小细胞肺癌中ATF3表达与临床特征及预后的关系。方法：回顾分析我院选取98例术后病理诊断为非小细胞肺癌的患者,于2007年1月-2009年5月在我院行肺癌根治术,选取同一患者距离肺癌组织≥5 cm切缘的正常肺组织作为对照组,同时分别选取正常肺组织30例及炎性肺组织30例分别进行检测。采用免疫组化法及RT-PCR检测肺组织中ATF3表达水平,并结合肺癌患者随访数据运用Kaplan-Meier方法进行生存期分析。结果：ATF3在非小细胞肺癌中呈高表达率,ATF3表达与淋巴结转移及TNM分期有显著差异性（P〈0.05）。生存分析提示ATF3的阳性组的生存期较ATF3阴性组的低（P〈0.001）。结论：ATF3蛋白在非小细胞肺癌表达水平与癌旁组、正常肺组织组及炎性肺组织的表达水平有显著差异性;且ATF3蛋白表达在淋巴结转移情况和TNM分期中有相关性;ATF3表达水平可作为肺癌患者术后预后判断的指标之一。

关键词： ACTIVATING TRANSCRIPTION FACTOR-3   NUCLEOTIDE EXCISION-REPAIR   INDUCED APOPTOSIS   HISTONE ACETYLTRANSFERASE   DNA-REPAIR   ACETYLATION   DEGRADATION   BINDING   IRRADIATION   SUPPRESSES  

摘要： The response to UV irradiation is important for a cell to maintain its genetic integrity when challenged by environmental genotoxins. An immediate early response to UV irradiation is the rapid induction of activating transcription factor 3 (ATF3) expression. Although emerging evidence has linked ATF3 to stress pathways regulated by the tumor suppressor p53 and the histone acetyltransferase Tip60, the role of ATF3 in the UV response remains largely unclear. Here, we report that ATF3 mediated dichotomous UV responses. Although UV irradiation enhanced the binding of ATF3 to Tip60, knockdown of ATF3 expression decreased Tip60 stability, thereby impairing Tip60 induction by UV irradiation. In line with the role of Tip60 in mediating UV-induced apoptosis, ATF3 promoted the death of p53-defective cells in response to UV irradiation. However, ATF3 could also activate p53 and promote p53-mediated DNA repair, mainly through altering histone modifications that could facilitate recruitment of DNA repair proteins (such as DDB2) to damaged DNA sites. As a result, ATF3 rather protected the p53 wild-type cells from UV-induced apoptosis. Our results thus indicate that ATF3 regulates cell fates upon UV irradiation in a p53-dependent manner.

关键词： ACTIVATED PROTEIN-KINASE   MACROPHAGE INHIBITORY CYTOKINE-1   ADAPTIVE-RESPONSE GENE   MESENCHYMAL TRANSITION   TRANSCRIPTION FACTOR-3   DRUG-RESISTANCE   STEM-CELLS   P53   APOPTOSIS   ATF3  

摘要： Colorectal cancer (CRC) as an environmental disease is largely influenced by accumulated epithelial stress from diverse environmental causes. We are exposed to ribosome-related insults, including ribosome-inactivating stress (RIS), from the environment, dietary factors, and medicines, but their physiological impacts on the chemotherapy of CRC are not yet understood. Here we revealed the effects of RIS on chemosensitivity and other malignancy-related properties of CRC cells. First, RIS led to bidirectional inhibition of p53-macrophage inhibitory cytokine 1 (MIC-1)-mediated death responses in response to anticancer drugs by either enhancing ATF3-linked antiapoptotic signaling or intrinsically inhibiting MIC-1 and p53 expression, regardless of ATF3. Second, RIS enhanced the epithelial-mesenchymal transition and biogenesis of cancer stem-like cells in an ATF3-dependent manner. These findings indicate that gastrointestinal exposure to RIS interferes with the efficacy of chemotherapeutics, mechanistically implying that ATF3-linked malignancy and chemoresistance can be novel therapeutic targets for the treatment of environmentally aggravated cancers.

关键词： ATF3   ChIP-seq   Enhancer   p300   H3K27ac   p53   PROTEIN SUPPRESSES   INDUCIBLE GENE   DNA-DAMAGE   HISTONE H3   CANCER   P53   ENHANCERS   METHYLATION   EXPRESSION   PATTERNS  

摘要： Background: Dysregulation of the common stress responsive transcription factor ATF3 has been causally linked to many important human diseases such as cancer, atherosclerosis, infections, and hypospadias. Although it is believed that the ATF3 transcription activity is central to its cellular functions, how ATF3 regulates gene expression remains largely unknown. Here, we employed ATF3 wild-type and knockout isogenic cell lines to carry out the first comprehensive analysis of global ATF3-binding profiles in the human genome under basal and stressed (DNA damage) conditions. Results: Although expressed at a low basal level, ATF3 was found to bind a large number of genomic sites that are often associated with genes involved in cellular stress responses. Interestingly, ATF3 appears to bind a large portion of genomic sites distal to transcription start sites and enriched with p300 and H3K27ac. Global gene expression profiling analysis indicates that genes proximal to these genomic sites were often regulated by ATF3. While DNA damage elicited by camptothecin dramatically altered the ATF3 binding profile, most of the genes regulated by ATF3 upon DNA damage were pre-bound by ATF3 before the stress. Moreover, we demonstrated that ATF3 was co-localized with the major stress responder p53 at genomic sites, thereby collaborating with p53 to regulate p53 target gene expression upon DNA damage. Conclusions: These results suggest that ATF3 likely bookmarks genomic sites and interacts with other transcription regulators to control gene expression.

关键词： 肝细胞癌   转录激活因子3   蛋白质类  

摘要： 目的筛选及验证肝癌细胞中与转录激活因子3（ATF3）相互结合的蛋白质，初步探讨在肝癌发生发展中协助ATF3发挥生物学功能的相关分子机制。方法应用免疫沉淀法沉淀出HepG2细胞中与ATF3相互结合的蛋白，经变性聚丙烯凝胶分析，与空载体组比对，挑选出差异性的电泳条带进行蛋白质谱分析，筛选出候选蛋白；再经免疫共沉淀验证二者是否相互结合；应用免疫组织化学及Westernblot检测并分析ATF3和候选蛋白在肝癌中的表达模式。结果过表达ATF3的HepG2实验组呈现出差异性表达的电泳条带；经质谱检测，Mascot软件分析及NCBI数据库检索，得到候选蛋白肽段信息，结合前期实验结果，PubMed文献报道，从中筛选出与ATF3最可能相关的蛋白gelsolin（GSN）；免疫共沉淀结果验证了ATI^3与GSN相互结合的关系，免疫组织化学及Westernblot检测出肝癌组织中ATF3与GSN的表达模式一致。结论ATF3可能通过与GSN蛋白之间的相互作用，在肝癌形成过程中协同发挥抑癌作用。

关键词： brain ischemia   MCAO   ATF3   lentiviral overexpression   glutamate neurotoxicity   reporter assay   CEREBRAL-ARTERY OCCLUSION   REACTIVE ASTROCYTOSIS   NMDA RECEPTORS   BRAIN-INJURY   EXPRESSION   DEATH   EXCITOTOXICITY   INHIBITION   APOPTOSIS   STRESS  

摘要： This study evaluates the pathological role of the stress sensor activating transcription factor-3 (ATF3) in ischemic neurotoxicity. Upregulation of the transcript and protein for ATF3 was seen 2-10 hr after reperfusion in the ipsilateral cerebral hemisphere of mice with transient middle cerebral artery occlusion for 2 hr. Immunohistochemical analysis confirmed the expression of ATF3 by cells immunoreactive for a neuronal marker in neocortex, hippocampus, and striatum within 2 hr after reperfusion. In murine neocortical neurons previously cultured under ischemic conditions for 2 hr, transient upregulation of both Atf3 and ATF3 expression was similarly found during subsequent culture for 2-24 hr under normoxia. Lentiviral overexpression of ATF3 ameliorated the neurotoxicity of glutamate (Glu) in cultured murine neurons along with a slight but statistically significant inhibition of both Fluo-3 and rhodamine-2 fluorescence increases by N-methyl-D-aspartate. Similarly, transient upregulation was seen in Atf3 and ATF3 expression during the culture for 48 hr in neuronal Neuro2A cells previously cultured under ischemic conditions for 2 hr. Luciferase reporter analysis with ATF3 promoter together with immunoblotting revealed the possible involvement of several transcription factors responsive to extracellular and intracellular stressors in the transactivation of the Atf3 gene in Neuro2A cells. ATF3 could be upregulated to play a role in mechanisms underlying mitigation of the neurotoxicity mediated by the endogenous neurotoxin Glu at an early stage after ischemic signal inputs. (c) 2016 Wiley Periodicals, Inc.

关键词： STAPHYLOCOCCUS aureus   LISTERIA monocytogenes  

摘要： A correction to the article 'ATF3 provides protection from Staphylococcus aureus and Listeria monocytogenes infections' that was published in the April 19, 2016 issue is presented.