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The epoxy propanol molecular cage bonded silica stationary phase, RCC3-GLD@silica, synthesized through the ring-opening reaction of secondary amine with epoxy propanol using RCC3-R as the scaffold unit, was successfully prepared as confirmed by infrared spectroscopy, thermogravimetric analysis, and nitrogen adsorption-desorption characterization. This stationary phase demonstrated excellent separation performance in both reversed-phase and hydrophilic chromatography modes, effectively separating a wide variety of compounds including alkylbenzenes, polycyclic aromatic hydrocarbons, phenols, anilines, sulfonamides, nucleosides, amino acids, sugars, and acids. The development of RCC3-GLD@silica benefits from the synergistic effects of its hydrophobic and hydrophilic actions, as evidenced by the U-shaped characteristic of the retention factor for nucleoside compounds with changes in the aqueous content of the mobile phase, further confirming the simultaneous presence of reversed-phase and hydrophilic chromatography mechanisms. Not only did this stationary phase successfully separate 33 compounds in reversed-phase chromatography mode, but it also separated 54 compounds in hydrophilic interaction chromatography mode, showcasing its broad separation capability from weakly polar to strongly polar compounds on a single chromatographic column. This indicates a wide application prospect in the field of chromatographic analysis.
Assuntos
Cromatografia de Fase Reversa , Interações Hidrofóbicas e Hidrofílicas , Nucleosídeos , Dióxido de Silício , Dióxido de Silício/química , Cromatografia de Fase Reversa/métodos , Nucleosídeos/isolamento & purificação , Nucleosídeos/química , Compostos de Epóxi/química , Aminoácidos/isolamento & purificação , Aminoácidos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/química , Fenóis/isolamento & purificação , Fenóis/química , Cromatografia Líquida de Alta Pressão/métodosRESUMO
After the publication of the article, an interested reader drew to the authors' attention that, in the western blots shown in Fig. 5C and D, a pair of data panels were inadvertently duplicated comparing between panels (C) and (D); in addition, the cell migration data shown in Fig. 7F on p. 1852 were selected incorrectly. The authors have examined their original data, and realize that these errors arose inadvertently as a consequence of their mishandling of their data. The revised versions of Figs. 5 and 7, featuring the corrected data for the caspase-8 experiment in Fig. 5C and alternative data for the cell migration assay experiments in Fig. 7F, are shown on the next two pages. The revised data shown for these Figures do not affect the overall conclusions reported in the paper. All the authors agree to the publication of this corrigendum, and are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish this. Furthermore, the authors apologize to the readership for any inconvenience caused. [Oncology Reports 40: 1843-1854, 2018; DOI: 10.3892/or.2018.6593].
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The blood-brain barrier (BBB) serves as a defensive line protecting the central nervous system, while also maintaining micro-environment homeostasis and inhibiting harmful materials from the peripheral blood. However, the BBB's unique physiological functions and properties make drug delivery challenging for patients with central nervous system diseases. In this article, we briefly describe the cell structure basis and mechanism of action of the BBB, as well as related functional proteins involved. Additionally, we discuss the various mechanisms of BBB damage following the onset of an ischemic stroke, and lastly, we mention several therapeutic strategies accounting for impairment mechanisms. We hope to provide innovative ideas for drug delivery research via the BBB.
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PKM2 is an important regulator of the aerobic glycolysis that plays a vital role in cancer cell metabolic reprogramming. In general, Trib2 is considered as a "pseudokinase", contributing to different kinds of cancer. However, the detailed roles of TRIB2 in regulating cancer metabolism by PKM2 remain unclear. This study demonstrated that TRIB2, not a "pseudokinase", has the kinase activity to directly phosphorylate PKM2 at serine 37 in cancer cells. The elevated pSer37-PKM2 would subsequently promote the PKM2 dimers to enter into nucleus and increase the expression of LDHA, GLUT1, and PTBP1. The aerobic glycolysis is then elevated to promote cancer cell proliferation and migration in TRIB2- or PKM2-overexpressed cultures. The glucose uptake and lactate production increased, but the ATP content decreased in TRIB2- or PKM2-treated cultures. Experiments of TRIB2-/- mice further supported that TRIB2 could regulate aerobic glycolysis by PKM2. Thus, these results reveal the new kinase activity of TRIB2 and its mechanism in cancer metabolism may be related to regulating PKM2 to promote lung cancer cell proliferation in vitro and in vivo, suggesting promising therapeutic targets for cancer therapy by controlling cancer metabolism.
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Ischemia-induced neuronal death leads to serious lifelong neurological deficits in ischemic stroke patients. Histone deacetylase 6 (HDAC6) is a promising target for neuroprotection in many neurological disorders, including ischemic stroke. However, the mechanism by which HDAC6 inhibition protects neurons after ischemic stroke remains unclear. Here, we discovered that genetic ablation or pharmacological inhibition of HDAC6 reduced brain injury after ischemic stroke by increasing macrophage migration inhibitory factor (MIF) acetylation. Mass spectrum analysis and biochemical results revealed that HDAC6 inhibitor or aspirin treatment promoted MIF acetylation on the K78 residue. MIF K78 acetylation suppressed the interaction between MIF and AIF, which impaired MIF translocation to the nucleus in ischemic cortical neurons. Moreover, neuronal DNA fragmentation and neuronal death were impaired in the cortex after ischemia in MIF K78Q mutant mice. Our results indicate that the neuroprotective effect of HDAC6 inhibition and aspirin treatment results from MIF K78 acetylation; thus, MIF K78 acetylation may be a therapeutic target for ischemic stroke and other neurological diseases.
Assuntos
Oxirredutases Intramoleculares , AVC Isquêmico , Fatores Inibidores da Migração de Macrófagos , Doenças do Sistema Nervoso , Neurônios , Acetilação , Animais , Aspirina/farmacologia , Desacetilase 6 de Histona/metabolismo , Humanos , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , AVC Isquêmico/genética , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Fatores Inibidores da Migração de Macrófagos/genética , Fatores Inibidores da Migração de Macrófagos/metabolismo , Camundongos , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , Neurônios/metabolismo , Neurônios/patologiaRESUMO
Non-coding RNAs (ncRNAs) involve in diverse biological processes by post-transcriptional regulation of gene expression. Emerging evidence shows that miRNA-4293 plays a significant role in the development of non-small cell lung cancer. However, the oncogenic functions of miR-4293 have not been studied. Our results demonstrated that miR-4293 expression is markedly enhanced in lung carcinoma tissue and cells. Moreover, miR-4293 promotes tumor cell proliferation and metastasis but suppresses apoptosis. Mechanistic investigations identified mRNA-decapping enzyme 2 (DCP2) as a target of miR-4293 and its expression is suppressed by miR-4293. DCP2 can directly or indirectly bind to WFDC21P and downregulates its expression. Consequently, miR-4293 can further promote WFDC21P expression by regulating DCP2. With a positive correlation to miR-4293 expression, WFDC21P also plays an oncogenic role in lung carcinoma. Furthermore, knockdown of WFDC21P results in functional attenuation of miR-4293 on tumor promotion. In vivo xenograft growth is also promoted by both miR-4293 and WFDC21P. Overall, our results establish oncogenic roles for both miR-4293 and WFDC21P and demonstrate that interactions between miRNAs and lncRNAs through DCP2 are important in the regulation of carcinoma pathogenesis. These results provided a valuable theoretical basis for the discovery of lung carcinoma therapeutic targets and diagnostic markers based on miR-4293 and WFDC21P.
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Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , Regulação para Cima/genética , Adulto , Idoso , Animais , Apoptose/genética , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Modelos Biológicos , Ligação Proteica , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/metabolismoRESUMO
Astrocytes have multiple functions in the brain, including affecting blood vessel (BV) homeostasis and function. However, the underlying mechanisms remain elusive. Here, we provide evidence that astrocytic neogenin (NEO1), a member of deleted in colorectal cancer (DCC) family netrin receptors, is involved in blood vessel homeostasis and function. Mice with Neo1 depletion in astrocytes exhibited clustered astrocyte distribution and increased BVs in their cortices. These BVs were leaky, with reduced blood flow, disrupted vascular basement membranes (vBMs), decreased pericytes, impaired endothelial cell (EC) barrier, and elevated tip EC proliferation. Increased proliferation was also detected in cultured ECs exposed to the conditioned medium (CM) of NEO1-depleted astrocytes. Further screening for angiogenetic factors in the CM identified netrin-1 (NTN1), whose expression was decreased in NEO1-depleted cortical astrocytes. Adding NTN1 into the CM of NEO1-depleted astrocytes attenuated EC proliferation. Expressing NTN1 in NEO1 mutant cortical astrocytes ameliorated phenotypes in blood-brain barrier (BBB), EC, and astrocyte distribution. NTN1 depletion in astrocytes resulted in BV/BBB deficits in the cortex similar to those in Neo1 mutant mice. In aggregate, these results uncovered an unrecognized pathway, astrocytic NEO1 to NTN1, not only regulating astrocyte distribution, but also promoting cortical BV homeostasis and function.
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Astrócitos/metabolismo , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Homeostase , Proteínas de Membrana/metabolismo , Neovascularização Fisiológica , Netrina-1/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Netrina-1/genéticaRESUMO
BACKGROUND: Dendritic cell-associated C-type lectin-1 (Dectin-1) receptor has been reported to be involved in neuroinflammation in Alzheimer's disease and traumatic brain injury. The present study was designed to investigate the role of Dectin-1 and its downstream target spleen tyrosine kinase (Syk) in early brain injury after ischemic stroke using a focal cortex ischemic stroke model. METHODS: Adult male C57BL/6 J mice were subjected to a cerebral focal ischemia model of ischemic stroke. The neurological score, adhesive removal test, and foot-fault test were evaluated on days 1, 3, 5, and 7 after ischemic stroke. Dectin-1, Syk, phosphorylated (p)-Syk, tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) expression was analyzed via western blotting in ischemic brain tissue after ischemic stroke and in BV2 microglial cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) injury in vitro. The brain infarct volume and Iba1-positive cells were evaluated using Nissl's and immunofluorescence staining, respectively. The Dectin-1 antagonist laminarin (LAM) and a selective inhibitor of Syk phosphorylation (piceatannol; PIC) were used for the intervention. RESULTS: Dectin-1, Syk, and p-Syk expression was significantly enhanced on days 3, 5, and 7 and peaked on day 3 after ischemic stroke. The Dectin-1 antagonist LAM or Syk inhibitor PIC decreased the number of Iba1-positive cells and TNF-α and iNOS expression, decreased the brain infarct volume, and improved neurological functions on day 3 after ischemic stroke. In addition, the in vitro data revealed that Dectin-1, Syk, and p-Syk expression was increased following the 3-h OGD and 0, 3, and 6 h of reperfusion in BV2 microglial cells. LAM and PIC also decreased TNF-α and iNOS expression 3 h after OGD/R induction. CONCLUSION: Dectin-1/Syk signaling plays a crucial role in inflammatory activation after ischemic stroke, and further investigation of Dectin-1/Syk signaling in stroke is warranted.
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Inflamação/metabolismo , Lectinas Tipo C/metabolismo , Acidente Vascular Cerebral/metabolismo , Quinase Syk/metabolismo , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/fisiologia , Acidente Vascular Cerebral/patologiaRESUMO
Neogenin is a transmembrane receptor critical for multiple cellular processes, including neurogenesis, astrogliogenesis, endochondral bone formation, and iron homeostasis. Here we present evidence that loss of neogenin contributes to pathogenesis of persistent hyperplastic primary vitreous (PHPV) formation, a genetic disorder accounting for ~ 5% of blindness in the USA. Selective loss of neogenin in neural crest cells (as observed in Wnt1-Cre; Neof/f mice), but not neural stem cells (as observed in GFAP-Cre and Nestin-Cre; Neof/f mice), resulted in a dysregulation of neural crest cell migration or delamination, exhibiting features of PHPV-like pathology (e.g. elevated retrolental mass), unclosed retinal fissure, and microphthalmia. These results demonstrate an unrecognized function of neogenin in preventing PHPV pathogenesis, implicating neogenin regulation of neural crest cell delamination/migration and retinal fissure formation as potential underlying mechanisms of PHPV.
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Movimento Celular/genética , Proteínas de Membrana/genética , Crista Neural/metabolismo , Vítreo Primário Hiperplásico Persistente/metabolismo , Animais , Desenvolvimento Embrionário/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microftalmia/genética , Microftalmia/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Vítreo Primário Hiperplásico Persistente/genética , Fenótipo , GravidezRESUMO
Lung cancer is the most common cause of cancerassociated mortality. MicroRNAs (miRNAs), as oncogenes or tumor suppressor genes, serve crucial roles not only in tumorigenesis, but also in tumor invasion and metastasis. Although miRNAlet7a (let7a) has been reported to suppress cell growth in multiple cancer types, the biological mechanisms of let7a in lung adenocarcinoma are yet to be fully elucidated. In the present study, the molecular roles of let7a in lung adenocarcinoma were investigated by detecting its expression in lung adenocarcinoma tissues and exploring its roles in the regulation of lung cancer cell proliferation. Let7a expression was identified to be downregulated in lung adenocarcinoma tissues compared with normal tissues. Overexpression of let7a effectively suppressed cancer cell proliferation, migration and invasion in H1299 and A549 cells. Let7a also induced cell apoptosis and cell cycle arrest. Furthermore, let7a significantly inhibited cell growth by directly regulating cyclin D1 signals. This novel regulatory mechanism of let7a in lung adenocarcinoma provides possible avenues for future targeted therapies of lung cancer.
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Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Ciclina D1/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Apoptose , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Pontos de Checagem do Ciclo Celular , Movimento Celular , Ciclina D1/genética , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Transdução de Sinais , Taxa de Sobrevida , Células Tumorais CultivadasRESUMO
Adult neurogenesis in hippocampal dentate gyrus (DG) is a complex, but precisely controlled process. Dysregulation of this event contributes to multiple neurological disorders, including major depression. Thus, it is of considerable interest to investigate how adult hippocampal neurogenesis is regulated. Here, we present evidence for neogenin, a multifunctional transmembrane receptor, to regulate adult mouse hippocampal neurogenesis. Loss of neogenin in adult neural stem cells (NSCs) or neural progenitor cells (NPCs) impaired NSCs/NPCs proliferation and neurogenesis, whereas increased their astrocytic differentiation. Mechanistic studies revealed a role for neogenin to positively regulate Gli1, a crucial downstream transcriptional factor of sonic hedgehog, and expression of Gli1 into neogenin depleted NSCs/NPCs restores their proliferation. Further morphological and functional studies showed additional abnormities, including reduced dendritic branches and spines, and impaired glutamatergic neuro-transmission, in neogenin-depleted new-born DG neurons; and mice with depletion of neogenin in NSCs/NPCs exhibited depressive-like behavior. These results thus demonstrate unrecognized functions of neogenin in adult hippocampal NSCs/NPCs-promoting NSCs/NPCs proliferation and neurogenesis and preventing astrogliogenesis and depressive-like behavior, and suggest neogenin regulation of Gli1 signaling as a possible underlying mechanism.
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Transtorno Depressivo/prevenção & controle , Proteínas de Membrana/genética , Neurogênese , Animais , Proliferação de Células , Células Cultivadas , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Giro Denteado/patologia , Transtorno Depressivo/patologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Hipocampo/citologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Proteínas de Membrana/deficiência , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurogênese/efeitos dos fármacos , Tamoxifeno/farmacologia , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismoRESUMO
BACKGROUND AND PURPOSE: Lrp4 (low-density lipoprotein receptor-related protein 4) is predominantly expressed in astrocytes, where it regulates glutamatergic neurotransmission by suppressing ATP release. Here, we investigated Lrp4's function in ischemia/stroke-induced brain injury response, which includes glutamate-induced neuronal death and reactive astrogliosis. METHODS: The brain-specific Lrp4 conditional knockout mice (Lrp4GFAP-Cre), astrocytic-specific Lrp4 conditional knockout mice (Lrp4GFAP-creER), and their control mice (Lrp4f/f) were subjected to photothrombotic ischemia and the transient middle cerebral artery occlusion. After ischemia/stroke, mice or their brain samples were subjected to behavior tests, brain histology, immunofluorescence staining, Western blot, and quantitative real-time polymerase chain reaction. In addition, primary astrocytes and neurons were cocultured with or without oxygen and glucose deprivation and in the presence or absence of the antagonist for adenosine-A2AR (adenosine A2A receptor) or ATP-P2X7R (P2X purinoceptor 7) signaling. Gliotransmitters, such as glutamate, d-serine, ATP, and adenosine, in the condition medium of cultured astrocytes were also measured. RESULTS: Lrp4, largely expressed in astrocytes, was increased in response to ischemia/stroke. Both Lrp4GFAP-Cre and Lrp4GFAP-creER mice showed less brain injury, including reduced neuronal death, and impaired reactive astrogliosis. Mechanistically, Lrp4 conditional knockout in astrocytes increased ATP release and the production of ATP derivative, adenosine, which were further elevated by oxygen and glucose deprivation. Pharmacological inhibition of ATP-P2X7R or adenosine-A2AR signaling diminished Lrp4GFAP-creER's protective effect. CONCLUSIONS: The astrocytic Lrp4 plays an important role in ischemic brain injury response. Lrp4 deficiency in astrocytes seems to be protective in response to ischemic brain injury, likely because of the increased ATP release and adenosine-A2AR signaling.
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Trifosfato de Adenosina/metabolismo , Astrócitos/metabolismo , Lesões Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Receptor A2A de Adenosina/metabolismo , Receptores de LDL/metabolismo , Transdução de Sinais , Trifosfato de Adenosina/genética , Animais , Astrócitos/patologia , Lesões Encefálicas/genética , Lesões Encefálicas/patologia , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Proteínas Relacionadas a Receptor de LDL , Camundongos , Camundongos Knockout , Receptor A2A de Adenosina/genética , Receptores de LDL/genética , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismoRESUMO
OBJECTIVE: WW domain-containing protein 2 (WWP2) is an E3 ubiquitin ligase, which belongs to the NEDD4-like protein family. Recently, it is reported to play a key role in tumorigenesis and development of tumors such as prostate and lung cancer. However, there has been not related report on glioma until now. The aim of this study is to detect the expression of WWP2 and analyze its correlation to the pathological grade and tumor recurrence in patients with glioma. MATERIALS AND METHODS: Western blot and immunohistochemistry were separately used to detect the expression of WWP2 protein in 31 brain glioma tissue samples and 80 brain glioma paraffin specimens. The method of Kaplan-Meier was used to analyze the correlation between the WWP2 expression and glioma recurrence. RESULTS: The protein expression level of WWP2 in glioma tissue was significantly higher than that in nontumorous brain tissue (P < 0.05), and the protein expression level of WWP2 in high-grade glioma (Grade III-IV) was significantly higher than that in low-grade glioma (Grade I-II) (P < 0.05). Kaplan-Meier analysis indicated that the patients with high WWP2 expression had significantly shorter tumor recurrence time than the patients with low WWP2 expression (P < 0.05). CONCLUSION: Our study suggests that WWP2 may play a role in the genesis and development of glioma; it may be a potential biomarker to predict pathological grade and tumor recurrence in patients with glioma.
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Biomarcadores Tumorais/genética , Glioma/genética , Recidiva Local de Neoplasia/genética , Ubiquitina-Proteína Ligases/genética , Idoso , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologiaRESUMO
ß-transducin repeat-containing E3 ubiquitin protein ligase (ß-TrCP) serves as the substrate recognition subunit for the Skp1-Cullin1-F-box protein E3 ubiquitin ligase, which recognizes the double phosphorylated DSG (X)2+nS destruction motif in various substrates that are essential for numerous aspects of tumorigenesis and regulates several important signaling pathways. However, the biological significance of ß-TrCP in glioma progression remains largely unknown. A previous study by the authors demonstrated that the levels of ß-TrCP protein expression in brain glioma tissues were significantly lower compared with non-tumorous tissues and that higher grades of gliomas exhibited lower levels of ß-TrCP expression in comparison with lower glioma grades. In addition, low ß-TrCP expression was associated with poor prognosis in patients with glioma. Subsequently, the present study aimed to investigate the effect of ß-TrCP on migratory, invasive and proliferative abilities of glioma cells. ß-TrCP plasmids were transfected into cultured U251 and U87 glioma cells, and changes in migration, invasion and proliferation were analyzed using wound healing, Transwell and EdU assays. It was identified that the overexpression of ß-TrCP inhibited migration, invasion and proliferation in glioma cells. In summary, these results indicate that ß-TrCP may serve a protective role against the progression of glioma by suppressing cell migration, invasion and proliferation. The potential mechanism of ß-TrCP I glioma cells requires additional investigation.
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MicroRNAs play important roles in tumorigenesis of various types of cancers. MiR-320a can inhibits cell proliferation of some cancers, but the biologic roles of miR-320a in lung cancer need to be further studied. Here, we investigated the roles of miR-320a in suppressing the proliferation of lung adenocarcinoma cells. MiR-320a treatment was found to effectively suppress LTEP-a-2 and A549 cell proliferation, and induce more apoptotic cells with irradiation treatment compared with control treatment. Our results also showed that miR-320a, as a novel miRNA, directly regulated signal transducer and activator of transcription 3 (STAT3) and its signals, such as Bcl-2, Bax, and Caspase 3. The siRNA-inhibited STAT3 levels further proved its roles in regulating STAT3 signals. Moreover, miR-320a treatment effectively suppressed cancer cell growth in mice xenografts compared with controls, and significantly inhibited cell migration in vitro and in vivo. Our findings collectively demonstrated that miR-320a, by directly regulating STAT3 signals, not only suppressed cell proliferation and metastasis, but also enhanced irradiation-induced apoptosis of adenocarcinomia cells.
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Adenocarcinoma/genética , Adenocarcinoma/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , MicroRNAs/administração & dosagem , MicroRNAs/genética , Fator de Transcrição STAT3/metabolismo , Células A549 , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Adenocarcinoma de Pulmão , Animais , Proliferação de Células/genética , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
MicroRNAs (miRNAs) and Smad3, as key transcription factors in transforming growth factor-ß1 (TGF-ß1) signaling, help regulate various physiological and pathological processes. We investigated the roles of Smad3-regulated miRNAs with respect to lung adenocarcinoma cell apoptosis, proliferation, and metastasis. We observed that Smad3 and phospho-SMAD3 (p-Smad3) were decreased in miR-206- (or miR-140)-treated cells and there might be a feedback loop between miR-206 (or miR-140) and TGF-ß1 expression. Smad3-related miRNAs affected tribbles homolog 2 (TRIB2) expression by regulating trib2 promoter activity through the CAGACA box. MiR-206 and miR-140 inhibited lung adenocarcinoma cell proliferation in vitro and in vivo by suppressing p-Smad3/Smad3 and TRIB2. Moreover, lung adenocarcinoma data supported a suppressive role for miR-206/miR-140 and an oncogenic role for TRIB2-patients with higher TRIB2 levels had poorer survival. In summary, miR-206 and miR-140, as tumor suppressors, induced lung adenocarcinoma cell death and inhibited cell proliferation by modifying oncogenic TRIB2 promoter activity through p-Smad3. MiR-206 and miR-140 also suppressed lung adenocarcinoma cell metastasis in vitro and in vivo by regulating EMT-related factors.
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Adenocarcinoma/genética , Adenocarcinoma/patologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Oncogenes , Regiões Promotoras Genéticas/genética , Proteína Smad3/metabolismo , Células A549 , Adenocarcinoma de Pulmão , Animais , Sequência de Bases , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Camundongos , MicroRNAs/genética , Metástase Neoplásica , Ligação Proteica/genética , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/metabolismo , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Neurotransmission requires precise control of neurotransmitter release from axon terminals. This process is regulated by glial cells; however, the underlying mechanisms are not fully understood. We found that glutamate release in the brain was impaired in mice lacking low-density lipoprotein receptor-related protein 4 (Lrp4), a protein that is critical for neuromuscular junction formation. Electrophysiological studies revealed compromised release probability in astrocyte-specific Lrp4 knockout mice. Lrp4 mutant astrocytes suppressed glutamatergic transmission by enhancing the release of ATP, whose level was elevated in the hippocampus of Lrp4 mutant mice. Consequently, the mutant mice were impaired in locomotor activity and spatial memory and were resistant to seizure induction. These impairments could be ameliorated by blocking the adenosine A1 receptor. The results reveal a critical role for Lrp4, in response to agrin, in modulating astrocytic ATP release and synaptic transmission. Our findings provide insight into the interaction between neurons and astrocytes for synaptic homeostasis and/or plasticity.
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Astrócitos/metabolismo , Hipocampo/metabolismo , Receptores de LDL/metabolismo , Transmissão Sináptica/fisiologia , Trifosfato de Adenosina/metabolismo , Agrina/genética , Agrina/metabolismo , Animais , Proteínas Relacionadas a Receptor de LDL , Camundongos Knockout , Junção Neuromuscular/metabolismo , Plasticidade Neuronal/fisiologia , Terminações Pré-Sinápticas/metabolismo , Receptores Colinérgicos/metabolismo , Receptores de LDL/genéticaRESUMO
UNLABELLED: Neogenin, a DCC (deleted in colorectal cancer) family receptor, is highly expressed in neural stem cells (NSCs). However, its function in NSCs remains to be explored. Here we provide in vitro and in vivo evidence for neogenin's function in NSCs to promote neocortical astrogliogenesis, but not self-renewal or neural differentiation. Mechanistically, neogenin in neocortical NSCs was required for BMP2 activation of YAP (yes associated protein). The active/nuclear YAP stabilized phospho-Smad1/5/8 and was necessary for BMP2 induction of astrocytic differentiation. Deletion of yap in mouse neocortical NSCs caused a similar deficit in neocortical astrogliogenesis as that in neogenin mutant mice. Expression of YAP in neogenin mutant NSCs diminished the astrocytic differentiation deficit in response to BMP2. Together, these results reveal an unrecognized function of neogenin in increasing neocortical astrogliogenesis, and identify a pathway of BMP2-neogenin-YAP-Smad1 for astrocytic differentiation in developing mouse neocortex. SIGNIFICANCE STATEMENT: Astrocytes, a major type of glial cells in the brain, play important roles in modulating synaptic transmission and information processing, and maintaining CNS homeostasis. The abnormal astrocytic differentiation during development contributes to dysfunctions of synaptic plasticity and neuropsychological disorders. Here we provide evidence for neogenin's function in regulation of the neocortical astrocyte differentiation during mouse brain development. We also provide evidence for the necessity of neogenin in BMP2/Smad1-induced astrocyte differentiation through YAP. Thus, our findings identify an unrecognized function of neogenin in mouse neocortical astrocyte differentiation, and suggest a signaling pathway, BMP2-neogenin-YAP-Smad1, underlying astrogliogenesis in developing mouse neocortex.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Astrócitos/fisiologia , Proteína Morfogenética Óssea 2/metabolismo , Proteínas de Membrana/metabolismo , Neocórtex/fisiologia , Fosfoproteínas/metabolismo , Proteína Smad1/metabolismo , Animais , Astrócitos/citologia , Proteínas de Ciclo Celular , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neocórtex/citologia , Neurogênese/fisiologia , Regulação para Cima/fisiologia , Proteínas de Sinalização YAPRESUMO
Vacuolar protein sorting-35 (VPS35) is a retromer component for endosomal trafficking. Mutations of VPS35 have been linked to familial Parkinson's disease (PD). Here, we show that specific deletion of the VPS35 gene in dopamine (DA) neurons resulted in PD-like deficits, including loss of DA neurons and accumulation of α-synuclein. Intriguingly, mitochondria became fragmented and dysfunctional in VPS35-deficient DA neurons, phenotypes that could be restored by expressing VPS35 wild-type, but not PD-linked mutant. Concomitantly, VPS35 deficiency or mutation increased mitochondrial E3 ubiquitin ligase 1 (MUL1) and, thus, led to mitofusin 2 (MFN2) degradation and mitochondrial fragmentation. Suppression of MUL1 expression ameliorated MFN2 reduction and DA neuron loss but not α-synuclein accumulation. These results provide a cellular mechanism for VPS35 dysfunction in mitochondrial impairment and PD pathogenesis.
Assuntos
Neurônios Dopaminérgicos/fisiologia , Dinâmica Mitocondrial , Proteínas de Transporte Vesicular/genética , Animais , Células Cultivadas , Potencial da Membrana Mitocondrial , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/fisiologia , Proteínas Mitocondriais/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Transporte Proteico , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Transporte Vesicular/metabolismo , alfa-Sinucleína/metabolismoRESUMO
ß-transducin repeat-containing E3 ubiquitin protein ligase (ß-TrCP) targets a number of substrates essential for specific aspects of tumorigenesis. In addition, ß-TrCP regulates various important signaling pathways. As ß-TrCP is involved in regulating the ubiquitination and degradation of multiple oncogenes and tumor suppressors, the function of ß-TrCP varies between cancer types. At present, the association between ß-TrCP expression and clinicopathological factors in glioma is unknown. Therefore, the current study used western blotting and immunohistochemistry to investigate the expression of ß-TrCP protein in glioma tissue specimens. It was identified that ß-TrCP protein expression levels were significantly lower in glioma compared with non-tumorous human brain tissues. Furthermore, the higher the grade of glioma, the lower the level of ß-TrCP expression. Kaplan-Meier analysis demonstrated that patients with low ß-TrCP expression experienced significantly worse overall survival compared with patients with high ß-TrCP expression. The results indicate that downregulation of ß-TrCP may be associated with poor survival in patients with glioma. Together, the current data indicates that ß-TrCP may be applied as a useful indicator of glioma prognosis and may serve as an anticancer therapeutic target for glioma, however further investigation is required.