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Modular dynamic graph theory metrics effectively capture the patterns of dynamic information interaction during human brain development. While existing research has employed modular algorithms to examine the overall impact of dynamic changes in community structure throughout development, there is a notable gap in understanding the cross-community dynamic changes within different functional networks during early childhood and their potential contributions to the efficiency of brain information transmission. This study seeks to address this gap by tracing the trajectories of cross-community structural changes within early childhood functional networks and modeling their contributions to information transmission efficiency. We analyzed 194 functional imaging scans from 83 children aged 2 to 8 years, who participated in passive viewing functional magnetic resonance imaging sessions. Utilizing sliding windows and modular algorithms, we evaluated three spatiotemporal metrics-temporal flexibility, spatiotemporal diversity, and within-community spatiotemporal diversity-and four centrality metrics: within-community degree centrality, eigenvector centrality, between-community degree centrality, and between-community eigenvector centrality. Mixed-effects linear models revealed significant age-related increases in the temporal flexibility of the default mode network (DMN), executive control network (ECN), and salience network (SN), indicating frequent adjustments in community structure within these networks during early childhood. Additionally, the spatiotemporal diversity of the SN also displayed significant age-related increases, highlighting its broad pattern of cross-community dynamic interactions. Conversely, within-community spatiotemporal diversity in the language network exhibited significant age-related decreases, reflecting the network's gradual functional specialization. Furthermore, our findings indicated significant age-related increases in between-community degree centrality across the DMN, ECN, SN, language network, and dorsal attention network, while between-community eigenvector centrality also increased significantly for the DMN, ECN, and SN. However, within-community eigenvector centrality remained stable across all functional networks during early childhood. These results suggest that while centrality of cross-community interactions in early childhood functional networks increases, centrality within communities remains stable. Finally, mediation analysis was conducted to explore the relationships between age, brain dynamic graph metrics, and both global and local efficiency based on community structure. The results indicated that the dynamic graph metrics of the SN primarily mediated the relationship between age and the decrease in global efficiency, while those of the DMN, language network, ECN, dorsal attention network, and SN primarily mediated the relationship between age and the increase in local efficiency. This pattern suggests a developmental trajectory in early childhood from global information integration to local information segregation, with the SN playing a pivotal role in this transformation. This study provides novel insights into the mechanisms by which early childhood brain functional development impacts information transmission efficiency through cross-community adjustments in functional networks.
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Encéfalo , Imageamento por Ressonância Magnética , Rede Nervosa , Humanos , Pré-Escolar , Criança , Masculino , Feminino , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/crescimento & desenvolvimento , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Desenvolvimento Infantil/fisiologia , Rede de Modo Padrão/diagnóstico por imagem , Rede de Modo Padrão/fisiologia , Conectoma/métodosRESUMO
Constructing a built-in interfacial electric field (BIEF) is an effective approach to enhance the electrocatalysts performance, but it has been rarely demonstrated for electrochemical carbon dioxide reduction reaction (CO2RR) to date. Herein, for the first time, SnO2/LaOCl nanofibers (NFs) with BIEF is created by electrospinning, exhibiting a high Faradaic efficiency (FE) of 100% C1 product (CO and HCOOH) at -0.9--1.1 V versus reversible hydrogen electrode (RHE) and a maximum FEHCOOH of 90.1% at -1.2 VRHE in H-cell, superior to the commercial SnO2 nanoparticles (NPs) and LaOCl NFs. SnO2/LaOCl NFs also exhibit outstanding stability, maintaining negligible activity degradation even after 10 h of electrolysis. Moreover, their current density and FEHCOOH are almost 400 mA cm-2 at -2.31 V and 83.4% in flow-cell. The satisfactory CO2RR performance of SnO2/LaOCl NFs with BIEF can be ascribed to tight interface of coupling SnO2 NPs and LaOCl NFs, which can induce charge redistribution, rich active sites, enhanced CO2 adsorption, as well as optimized Gibbs free energy of *OCHO. The work reveals that the BIEF will trigger interfacial accumulation and stability enhancement effects in promoting CO2RR activity and stability of SnO2-based materials, providing a novel approach to develop stable and efficient CO2RR electrocatalysts.
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BACKGROUND: Breast cancer (BC) is a prevalent malignancy affecting women, characterized by a substantial occurrence rate. Squalene epoxidase (SQLE) is a crucial regulator of ferroptosis and has been associated with promoting cell growth and invasion in different types of human cancers. This study aimed to investigate the functional significance of SQLE in BC and elucidate the underlying molecular mechanisms involved. METHODS: SQLE expression levels in BC tissues were evaluated using quantitative real-time polymerase chain reaction, western blotting, and immunohistochemistry. Cell viability, invasion, migration, and cell cycle distribution were assessed using a combination of assays, including the Cell Counting Kit-8, EdU, colony formation, Transwell, and wound healing assays and flow cytometry analysis. Measurement of intracellular reactive oxygen species (ROS), malondialdehyde assay, and glutathione assay were utilized to investigate ferroptosis. Furthermore, co-immunoprecipitation and immunofluorescence assays were conducted to explore the correlation between SQLE and CCNB1. The in vivo tumor growth was evaluated by conducting a xenograft tumorigenicity assay to investigate the impact of SQLE. RESULTS: SQLE expression was significantly increased in BC, and higher SQLE expression levels were significantly associated with an unfavorable prognosis. In vitro functional assays revealed that the overexpression of SQLE markedly enhanced the proliferation, migration, and invasion capacities of BC cells. Furthermore, SQLE overexpression facilitated tumor growth in nude mice. Mechanistically, SQLE alleviated the ubiquitination modification of CCNB1, leading to enhanced stability of the CCNB1 protein and decreased intracellular ROS levels. Ultimately, this inhibited ferroptosis and facilitated the progression of BC. Our findings have provided insights into a crucial pathway by which elevated SQLE expression confers protection to BC cells against ferroptosis, thus promoting cancer progression. SQLE may serve as a novel oncological marker and a potential therapeutic target for BC progression. CONCLUSIONS: In conclusion, this study provides evidence that SQLE plays a regulatory role in BC progression by modulating CCNB1 and ferroptosis. These findings offer valuable insights into the role of SQLE in the pathogenesis of BC and demonstrate its potential as a therapeutic target for treating BC.
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Gemcitabine resistance is a frequently occurring and intractable obstacle in pancreatic cancer treatment. However, the underlying mechanisms require further investigation. Adaptive regulation of oxidative stress and aberrant activation of the NF-κB signaling pathway are associated with resistance to chemotherapy. Here, we found that gemcitabine upregulated the expression of CASC9 in a dose-dependent manner, partially via induction of reactive oxygen species, whereas inhibition of CASC9 expression enhanced gemcitabine-induced oxidative stress and apoptosis in pancreatic cancer cells. Furthermore, suppression of CASC9 level inhibited the expression of NRF2 and the downstream genes NQO1 and HO-1, and vice versa, indicating that CASC9 forms a positive feedback loop with NRF2 signaling and modulates the level of oxidative stress. Silencing CASC9 attenuated NF-κB pathway activation in pancreatic cancer cells and synergistically enhanced the cytotoxic effect of gemcitabine chemotherapy in vivo. In conclusion, our findings suggest that CASC9 plays a key role in driving resistance to gemcitabine through a reciprocal loop with the NRF2-antioxidant signaling pathway and by activating NF-κB signaling. Our study reveals potential targets that can effectively reverse resistance to gemcitabine chemotherapy.
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Gencitabina , Neoplasias Pancreáticas , Humanos , NF-kappa B/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Transdução de Sinais , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Linhagem Celular Tumoral , Neoplasias PancreáticasRESUMO
BACKGROUND: Pancreatic endocrine insufficiency is more likely to occur after acute pancreatitis (AP), but the risk factors affecting pancreatic endocrine function remain controversial. Therefore, exploring the incidence and risk factors of fasting hyperglycaemia following first-attack AP is important. METHODS: Data were collected from 311 individuals with first-attack AP without previous diabetes mellitus (DM) or impaired fasting glucose (IFG) history treated in the Renmin Hospital of Wuhan University. Relevant statistical tests were performed. A two-sided p-value < 0.05 was considered statistically significant. RESULTS: The incidence of fasting hyperglycaemia in individuals with first-attack AP was 45.3%. Univariate analysis showed that age (χ2 = 6.27, P = 0.012), aetiology (χ2 = 11.184, P = 0.004), serum total cholesterol (TC) (χ2 = 14.622, P < 0.001), and serum triglyceride (TG) (χ2 = 15.006, P < 0.001) were significantly different between the hyperglycaemia and non-hyperglycaemia groups (P < 0.05). The serum calcium concentration (Z=-2.480, P = 0.013) was significantly different between the two groups (P < 0.05). Multiple logistic regression analysis showed that age- ≥60 years (P < 0.001, OR = 2.631, 95%Cl = 1.529-4.527) and TG ≥ 5.65 mmol/L (P < 0.001, OR = 3.964, 95%Cl = 1.990-7.895) were independent risk factors for fasting hyperglycaemia in individuals with first-attack AP (P < 0.05). CONCLUSIONS: Old age, serum triglycerides, serum total cholesterol, hypocalcaemia, and aetiology are associated with fasting hyperglycaemia following first-attack AP. Age ≥ 60 years and TG ≥ 5.65 mmol/L are independent risk factors for fasting hyperglycaemia following first-attack AP.
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Insuficiência Pancreática Exócrina , Hiperglicemia , Pancreatite , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Incidência , Alta do Paciente , Doença Aguda , Fatores de Risco , Jejum , ColesterolRESUMO
Adenosylmethionine decarboxylase 1 (AMD1) has been implicated in carcinogenesis and tumor progression. However, the potential biomechanism and biological implications of AMD1 in breast cancer (BC) remain unclear. The purpose of this study was to investigate the effect of abnormal expression of AMD1 in BC. The expression of AMD1 in different human BC cell lines was studied by using western blotting and qRT-PCR. In vitro cell proliferation, clone formation, cell cycle and apoptosis assays were performed to explore the effect of AMD1 on cellular proliferation. Xenograft mouse models were established to elucidate the role of AMD1 in BC growth. The expression profiles of AMD1 in 28 pairs of BC tissues and adjacent noncancerous tissues (ANTs) were investigated by using western blotting and immunohistochemistry. The clinical implication and prognostic evaluation of AMD1 in BC were examined by excavating the online database. We found that the expression levels of AMD1 in BC cell lines were significantly higher than those in the normal human breast epithelial cell line MCF-10A. In addition, AMD1 potentiated proliferation, induced cell cycle progression and inhibited apoptosis in BC cells. Subcutaneous tumor xenografts also supported the promotive role of AMD1 in BC growth. We discovered that the level of AMD1 in BC tissues was significantly higher than that in ANTs. Using the online database, increased AMD1 was found to be associated with clinical indicators and predicted a poor prognosis in patients with BC. Our findings indicate that AMD1 elicits potent oncogenic effects on the malignant progression of BC. AMD1 might serve as a promising diagnostic biomarker and therapeutic target for patients with BC.
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Neoplasias da Mama , MicroRNAs , Adenosilmetionina Descarboxilase/genética , Adenosilmetionina Descarboxilase/metabolismo , Animais , Neoplasias da Mama/metabolismo , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , PoliaminasRESUMO
Surface strains are necessary to optimize the oxygen adsorption energy during the oxygen reduction reaction (ORR) in the four-electron process, but the surface strains regulation for ORR in the two-electron process to produce hydrogen peroxide (H2 O2 ) is rarely studied. Herein, it is reported that the tensile strained B-doped Ni nanoparticles on carbon support (Ni-B@BNC) could enhance the adsorption of O2 , stabilize OO bond, and boost the electrocatalytic ORR to H2 O2 . Moreover, the Ni-B@BNC catalysts exhibit volcano-type activity for electrocatalytic ORR to H2 O2 as a function of the strain intensity, which is controlled by B content. Among them, Ni4 -B1 @BNC exhibits the highest H2 O2 selectivity of over 86%, H2 O2 yield of 128.5 mmol h-1 g-1 , and Faraday efficiency of 94.9% at 0.6 V vs reversible hydrogen electrode as well as durable stability after successive cycling, being one of the state-of-the-art electrocatalysts for two-electron ORR. The density functional theory calculations reveal that tensile strain introduced by doping B into Ni nanoparticles could decrease the state density of Ni-3d orbital and optimize the binding energy of OOH* during ORR. A new direction is provided here for the design of highly active and stable catalysts for potential H2 O2 production and beyond.
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AIM: Given the fact that tumor-associated macrophage-derived extracellular vesicles (EVs) are attributable to tumor aggressiveness, this research intends to decode the mechanism of M2 macrophage-derived EVs in the differentiation and activities of pancreatic cancer (PaCa) stem cells via delivering microRNA (miR)-21-5p. METHODS: Polarized M2 macrophages were induced, from which EVs were collected and identified. miR-21-5p expression in M2 macrophage-derived EVs was tested. After cell sorting, CD24+CD44+EpCAM+ stem cells were co-cultured with M2 macrophages, in which miR-21-5p was upregulated or downregulated. The effects of M2 macrophage-derived EVs and miR-21-5p on Nanog/octamer-binding transcription factor 4 (Oct4) expression, sphere formation, colony formation, invasion and migration capacities, apoptosis, and in vivo tumorigenic ability were examined. Krüppel-like factor 3 (KLF3) expression and its interaction with miR-21-5p were determined. RESULTS: M2 macrophage-derived EVs promoted PaCa stem cell differentiation and activities. miR-21a-5p was upregulated in M2 macrophage-derived EVs. miR-21a-5p downregulation in M2 macrophage-derived EVs inhibited Nanog/Oct4 expression and impaired sphere-forming, colony-forming, invasion, migration, and anti-apoptosis abilities of PaCa stem cells in vitro and tumorigenic ability in vivo. miR-21-5p targeted KLF3 to mediate the differentiation and activities of PaCa stem cells, and KLF3 was downregulated in PaCa stem cells. CONCLUSION: This work explains that M2 macrophage-derived exosomal miR-21a-5p stimulates differentiation and activity of PaCa stem cells via targeting KLF3, paving a novel way for attenuating PaCa stemness.
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Vesículas Extracelulares , Fatores de Transcrição Kruppel-Like , Macrófagos , MicroRNAs , Células-Tronco Neoplásicas , Neoplasias Pancreáticas , Carcinogênese/metabolismo , Diferenciação Celular , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Macrófagos/metabolismo , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/genéticaRESUMO
How ion channels localize and distribute on the cell membrane remains incompletely understood. We show that interventions that vary cell adhesion proteins and cell size also affect the membrane current density of inward-rectifier K+ channels (Kir2.1; encoded by KCNJ2) and profoundly alter the action potential shape of excitable cells. By using micropatterning to manipulate the localization and size of focal adhesions (FAs) in single HEK293 cells engineered to stably express Kir2.1 channels or in neonatal rat cardiomyocytes, we establish a robust linear correlation between FA coverage and the amplitude of Kir2.1 current at both the local and whole-cell levels. Confocal microscopy showed that Kir2.1 channels accumulate in membrane proximal to FAs. Selective pharmacological inhibition of key mediators of protein trafficking and the spatially dependent alterations in the dynamics of Kir2.1 fluorescent recovery after photobleaching revealed that the Kir2.1 channels are transported to the cell membrane uniformly, but are preferentially internalized by endocytosis at sites that are distal from FAs. Based on these results, we propose adhesion-regulated membrane localization of ion channels as a fundamental mechanism of controlling cellular electrophysiology via mechanochemical signals, independent of the direct ion channel mechanogating.
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Integrinas/metabolismo , Ativação do Canal Iônico/fisiologia , Potenciais da Membrana/fisiologia , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Animais , Endocitose , Feminino , Células HEK293 , Humanos , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Breast cancer (BC) is one of the commonest female cancers, which is characterized with high incidence. Although treatments have been improved, the prognosis of BC patients in advanced stages remains unsatisfactory. Thus, exploration of the molecular mechanisms underneath BC progression is necessary to find novel therapeutic methods. Frizzled class receptor 2 (FZD2) belongs to Frizzled family, which has been proven to promote cell growth and invasion in various human cancers. The purpose of our current study was to detect the functions of FZD2 in BC and explore its underlying molecular mechanism. METHODS: The level of FZD2 was measured in BC tissues by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, immunohistochemistry (IHC), respectively. Cell Counting Kit-8 (CCK-8), colony formation assay, transwell assays, wound healing assay and flow cytometry analyses were separately conducted to detect cell viability, invasion, migration, apoptosis and cell cycle distribution. The levels of Epithelial-mesenchymal transition (EMT) biomarkers were examined by using Immunofluorescence assay. Xenograft tumorigenicity assay was performed to assess the effect of FZD2 on tumor growth in vivo. RESULTS: FZD2 mRNA and protein expression was abundant in BC tissues. Moreover, high level of FZD2 had significant correlation with poor prognosis in BC patients. In vitro functional assays revealed that silencing of FZD2 had suppressive effects on BC cell growth, migration and invasion. Animal study further demonstrated that FZD2 silencing inhibited BC cell growth in vivo. In addition, FZD2 induced EMT process in BC cells in a transforming growth factor (TGF)-ß1-dependent manner. Mechanistically, knockdown of FZD2 led to the inactivation of Notch signaling pathway. CONCLUSION: FZD2 facilitates BC progression and promotes TGF-ß1-inudced EMT process through activating Notch signaling pathway.
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BACKGROUND: Pancreatic cancer (PC), characterized with high growth rate and metastatic rate. It's urgently necessary to explore new mechanism of PC. Circular RNA/miRNA/mRNA network was widely reported to participate in the cancer progression. METHODS: In this research, circular RNA CDR1as (circCDR1as) was identified by microarray analysis and detected in pancreatic cancer (PC) tissues and cells. Transwell, colony-forming assay, nude mouse tumorigenicity assay were used to determine the function of circCDR1as in PC. Western blot, dual luciferase reporting test were applied to investigate the mechanism. RESULTS: We found that circCDR1as was highly expressed in PC tissues. The levels of circCDR1as in PC tissues and cells were higher than those in controls. CircCDR1as promoted the migration, invasion and proliferation of PC cells in vitro and tumor growth in vivo via mediating E2F3 expression by sponging miR-432-5p. CONCLUSIONS: In conclusion, circCDR1as could promote the development of PC and might be a novel diagnostic target for PC.
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Identification of proteins that interact with Cx43 has been instrumental in the understanding of gap junction (GJ) regulation. An in vitro phosphorylation screen identified that Protein tyrosine kinase 2 beta (Pyk2) phosphorylated purified Cx43CT and this led us to characterize the impact of this phosphorylation on Cx43 function. Mass spectrometry identified Pyk2 phosphorylates Cx43 residues Y247, Y265, Y267, and Y313. Western blot and immunofluorescence staining using HeLaCx43 cells, HEK 293 T cells, and neonatal rat ventricular myocytes (NRVMs) revealed Pyk2 can be activated by Src and active Pyk2 interacts with Cx43 at the plasma membrane. Overexpression of Pyk2 increases Cx43 phosphorylation and knock-down of Pyk2 decreases Cx43 phosphorylation, without affecting the level of active Src. In HeLaCx43 cells treated with PMA to activate Pyk2, a decrease in Cx43 GJ intercellular communication (GJIC) was observed when assayed by dye transfer. Moreover, PMA activation of Pyk2 could be inhibited by the small molecule PF4618433. This partially restored GJIC, and when paired with a Src inhibitor, returned GJIC to the no PMA control-level. The ability of Pyk2 and Src inhibitors to restore Cx43 function in the presence of PMA was also observed in NRVMs. Additionally, an animal model of myocardial infarction induced heart failure showed a higher level of active Pyk2 activity and increased interaction with Cx43 in ventricular myocytes. Src inhibitors have been used to reverse Cx43 remodeling and improve heart function after myocardial infarction; however, they alone could not fully restore proper Cx43 function. Our data suggest that Pyk2 may need to be inhibited, in addition to Src, to further (if not completely) reverse Cx43 remodeling and improve intercellular communication.
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Comunicação Celular , Conexina 43/metabolismo , Quinase 2 de Adesão Focal/antagonistas & inibidores , Junções Comunicantes/metabolismo , Quinases da Família src/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Linhagem Celular , Conexina 43/química , Modelos Animais de Doenças , Quinase 2 de Adesão Focal/metabolismo , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/patologia , Ventrículos do Coração/patologia , Humanos , Mutação/genética , Fosforilação , Ligação Proteica , Domínios Proteicos , Ratos , Acetato de Tetradecanoilforbol/farmacologia , Quinases da Família src/genética , Quinases da Família src/metabolismoRESUMO
Gap junctions are intercellular conduits that permit the passage of ions, small metabolites, and signaling molecules between cells. Connexin32 (Cx32) is a major gap junction protein in the liver and brain. Phosphorylation is integral to regulating connexin assembly, degradation, and electrical and metabolic coupling, as well as to interactions with molecular partners. Cx32 contains two intracellular tyrosine residues, and tyrosine phosphorylation of Cx32 has been detected after activation of the epidermal growth factor receptor; however, the specific tyrosine residue and the functional implication of this phosphorylation remain unknown. To address the limited available information on Cx32 regulation by tyrosine kinases, here we used the Cx32 C-terminal (CT) domain in an in vitro kinase-screening assay, which identified ephrin (Eph) receptor family members as tyrosine kinases that phosphorylate Cx32. We found that EphB1 and EphA1 phosphorylate the Cx32CT domain residue Tyr243 Unlike for Cx43, the tyrosine phosphorylation of the Cx32CT increased gap junction intercellular communication. We also demonstrated that T-cell protein-tyrosine phosphatase dephosphorylates pTyr243 The data presented above along with additional examples throughout the literature of gap junction regulation by kinases, indicate that one cannot extrapolate the effect of a kinase on one connexin to another.
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Conexinas/metabolismo , Junções Comunicantes/metabolismo , Receptor EphA1/metabolismo , Receptor EphB1/metabolismo , Células CACO-2 , Conexina 43/genética , Conexina 43/metabolismo , Conexinas/genética , Junções Comunicantes/genética , Células HeLa , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 2 , Receptor EphA1/genética , Receptor EphB1/genética , Proteína beta-1 de Junções ComunicantesRESUMO
Breast cancer is the most common cancer in women worldwide and can be classified into multiple subtypes, including triple-negative breast cancer (TNBC). TNBC is more aggressive than other types of breast cancer and has a poor prognosis. However, excluding chemotherapy, the treatment of TNBC does not involve targeted therapy. The dysregulated expression of lncRNAs plays a vital role in the development of numerous cancers. Thus, the aim of this meta-analysis is to determine the functional roles of lncRNAs in TNBC. We performed a systematic search for articles related to TNBC using multiple online databases, including PubMed, EMBASE, Web of Science, and Science-Direct. We collated pooled hazard ratios with 95% confidence interval to estimate the prognostic value of lncRNAs. We assessed the quality of studies using the Newcastle-Ottawa scale. Data were collected from cohort studies that compared overall survival, disease-free survival, and relapse-free survival between patients with high and patients with low expression of lncRNAs. Using 2,192 samples from 21 studies, we observed a correlation between poor prognosis and the upregulation of 14 lncRNAs (LINC00173, HUMT, HOTAIR, LUCAT1, HIF1A-AS2, ZEB2-AS1, NAMPT-AS, DANCR, LINC01638, ZNF469-3, AFAP1-AS1, ANRIL, MALAT1, and HULC) and downregulation of four lncRNAs (MIR503HG, NEF, TC0NS_12_00002973, and GAS5). The pooled hazard ratios for the correlation between differentially expressed lncRNAs and overall, disease-free, and relapse-free survival were 2.38 (2.03-2.78), 2.19 (1.51-3.16), and 3.19 (0.81-12.53), respectively. This meta-analysis shows that the expression of candidate lncRNAs may reliably predict the prognosis of patients with TNBC.
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RNA Longo não Codificante/genética , Neoplasias de Mama Triplo Negativas/genética , Feminino , Humanos , Prognóstico , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
Phosphorylation regulates connexin43 (Cx43) function from assembly/disassembly to coupling at the plaque. Src is a tyrosine kinase known to both phosphorylate Cx43 (residues Y247 and Y265) and affect gap junction intercellular communication. However, the Cx43 carboxyl-terminal (CT) domain contains additional tyrosine residues and proteomic discovery mass spectrometry data identified Y313 as a potential phosphorylation target. Based upon the study of Lin et al. (2001) J. Cell Biol., which still observed tyrosine phosphorylation by Src when using a Cx43 Y247/Y265F mutant, we addressed the possibility of Y313 phosphorylation (pY313) by Src. In vitro Src phosphorylation of purified Cx43CT followed by mass spectroscopy revealed that Src also phosphorylates Y313. This observation was confirmed by repeating the in vitro phosphorylation using different combinations of Cx43CT Yâ¯ââ¯F mutants and a general anti-pTyr antibody. Next, a phospho-specific antibody was generated to help characterize the importance of pY313. We established an in cyto experimental system by stably expressing Cx43 WT and mutants (Y247F, Y265F, Y313F, Y247/265F, Y247/313F, Y265/313F, or Y247/265/313F) in Cx43-deficient HeLa cells. Cx43 WT and mutants, in the absence of v-Src, localized to the plasma membrane and formed gap junctions. When v-Src was over-expressed, Cx43 WT localized intracellularly, while all of the single and double mutants remained able to form plaques and transfer dye, albeit variable in number and amount, respectively. Complete Src-resistance was only achieved with the Cx43 Y247/265/313F mutant. Furthermore, Cx43 Y265F inhibited the ability of v-Src to phosphorylate Y247 and Y313 as well as phosphorylation at both Y265 and Y313 was necessary to inhibit the Cx43 interaction with Drebrin. Finally, we observed in diseased cardiac tissue, in which Src is active, an increase in intercalated disc and intracellular localized Cx43 pY313.
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Conexina 43/metabolismo , Junções Comunicantes/metabolismo , Neuropeptídeos/metabolismo , Fosfotirosina/metabolismo , Quinases da Família src/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos/metabolismo , Especificidade de Anticorpos , Conexina 43/química , Células HeLa , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Fosforilação , Ligação Proteica , RatosRESUMO
Several studies have shown an important role for long non-coding RNA (lncRNA) in breast cancer progression. The present study investigated the role of lncRNA Opa interacting protein 5-antisense RNA 1 (OIP5-AS1) in the progression of breast cancer. OIP5-AS1 was significantly upregulated in breast cancer tissues and in breast cancer cell lines, and OIP5-AS1 downregulation inhibited the malignant behavior of breast cancer in vitro and in vivo. For in-depth exploration of the mechanism of OIP5-AS1 in breast cancer, we found that expression of microRNA-129-5p(miR-129-5p), which was found to bind sites in the sequence of OIP5-AS1, in breast cancer tissues was negatively correlated with OIP5-AS1. Also, luciferase assays indicated that OIP5-AS1 acted as a miR-129-5p sponge, resulting in upregulated expression of the sex-determining region Y-box 2 (SOX2) transcription factor. Our study showed that OIP5-AS1 plays a critical role in promoting breast cancer progression and that OIP5-AS1 downregulation targets SOX2 by miR-129-5p upregulation.
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Neoplasias da Mama/genética , Regulação para Baixo , MicroRNAs/genética , RNA Longo não Codificante/genética , Fatores de Transcrição SOXB1/genética , Regulação para Cima , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/metabolismo , Interferência de RNA , RNA Longo não Codificante/metabolismo , Terapêutica com RNAi/métodos , Fatores de Transcrição SOXB1/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Growth suppression mediated by connexin 37 (Cx37; also known as GJA4) requires interaction between its C-terminus and functional pore-forming domain. Using rat insulinoma cells, we show that Cx37 induces cell death and cell cycle arrest, and slowed cell cycling. Whether differential phosphorylation might regulate intramolecular interactions, and consequently the growth-suppressive phenotype, is unknown. Protein kinase C inhibition increased the open state probability of low-conductance gap junction channels (GJChs) and reduced GJCh closed state probability. Substituting alanine at serine residues 275, 302 and 328 eliminated Cx37-induced cell death, supported proliferation and reduced the GJCh closed state probability. With additional alanine for serine substitutions at residues 285, 319, 321 and 325, Cx37-induced cell death was eliminated and the growth arrest period prolonged, and GJCh closed state probability was restored. With aspartate substitution at these seven sites, apoptosis was induced and the open state probability of large conductance GJChs (and hemichannels) was increased. These data suggest that differential phosphorylation of the C-terminus regulates channel conformation and, thereby, cell cycle progression and cell survival.
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Ciclo Celular/fisiologia , Conexinas/metabolismo , Junções Comunicantes/metabolismo , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Conexinas/genética , Junções Comunicantes/genética , Mutação de Sentido Incorreto , Fosforilação , RatosRESUMO
BACKGROUND: Aged people all over the world are prone to fall down accidentally and be injured with fracture, such as the rib fracture. To protect the elderly, the safety vest has been developed to protect them from being injured when falling down. To effectively protect the elderly, more analysis on the protective capacity of a safety vest under different situation are needed. RESULTS: Herein, a finite element model based on the computed tomography CT scanning data of a Chinese old female was built, and then used to simulate the process of falling down at different velocities. Analysis and comparison were done on the maximum shear stress, kinetic energy curves and internal energy curves with and without safety vest. The maximum shear stress indicated that the Abbreviated Injury Scale (AIS) 2+ injury risks of rib were 8%, 100% and 100% at the velocities of 1.5 m/s, 2.0 m/s and 2.5 m/s, respectively. The corresponding risks were lowered to 0%, 0% and 60% by the vest, respectively. Furthermore, the vest could absorb the internal energy resulted by the deformation of the thoracic osseous tissue by about 20%, thus decreasing the shear stress and the injury risk. CONCLUSION: It is concluded that the safety vest decreases the injury risk when the elderly fall down, thus protects them from being injured.
Assuntos
Acidentes por Quedas , Análise de Elementos Finitos , Fenômenos Mecânicos , Roupa de Proteção , Segurança , Traumatismos Torácicos/etiologia , Traumatismos Torácicos/prevenção & controle , Idoso , Feminino , Humanos , Estresse Mecânico , Traumatismos Torácicos/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
Neuropathic pain is a complex, chronic pain condition and the treatment is a major clinical challenge. Recent studies have shown that two FDA approved drugs dexmedetomidine (DEX) and midazolam (MZL), may be useful in treating neuropathic pain, but the mechanism is not fully dementated. Here, we investigated the effects and mechanisms of DEX and MZL treatment in the peripheral nerve injury model. Intramuscular injection with DEX and MZL attenuated the development of mechanical allodynia and thermal hyperalgesia in rats with chronic constriction injury (CCI). Concurrently, the expression of NMDA receptor subunit 2B (NR2B), GABA (A) receptor subunit alpha1 (GABAA-α1), and Sonic Hedgehog (SHH) displayed different temporal patterns in the thalamus and the ipsilateral dorsal horn of the spinal cord after CCI. Such that (1) NR2B expression was decreased on day 1 and 14, whereas GABAA-α1 expression was increased on day 1 in the thalamus, and NR2B expression was decreased on day 1, whereas GABAA-α1 expression was increased on day 1 and day 30 in the ipsilateral spinal cord dorsal horn after DEX treatment. (2) NR2B expression was increased on day 1, then decreased on day 14 and returned to baseline on day30, whereas GABAA-α1 expression was no significant changes on day 1, 14, 30 in the thalamus, and NR2B expression was decreased on day 14 and 30, whereas GABAA-α1 expression was no changes on day 1 and 14 but increased on day 30 after MZL treatment. Furthermore, the mechanical allodynia was significantly attenuated after PUR administration. Meanwhile the expression of NR2B was significantly decreased, and the expression of GABAA-α1 was significantly increased, in the thalamus and in the ipsilateral spinal cord dorsal horn when detected on postoperative day 1, 7, and 14. Our findings indicate that DEX and MZL have different mechanisms in CCI rats, suggesting different strategies could be considered in managing neuropathic pain in different individuals. © 2018 IUBMB Life, 70(2):143-152, 2018.
Assuntos
Dexmedetomidina/farmacologia , Midazolam/farmacologia , Traumatismos dos Nervos Periféricos/tratamento farmacológico , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Modelos Animais de Doenças , Proteínas Hedgehog/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Masculino , Neuralgia/tratamento farmacológico , Traumatismos dos Nervos Periféricos/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Corno Dorsal da Medula Espinal/efeitos dos fármacos , Corno Dorsal da Medula Espinal/metabolismo , Tálamo/efeitos dos fármacos , Tálamo/metabolismoRESUMO
Adriamycin resistance is closely related to therapeutic efficacy in breast cancer patients and their prognosis. Increasing evidence has suggested that miRNA functions in Adriamycin resistance in various types of cancer. microRNA-129-5p (miR-129-5p) has been considered a tumor-suppressive miRNA in several cancers, but its potential role in Adriamycin resistance in breast cancer has not been fully elucidate. By qRT-PCR assay, we revealed that the expression of miR-129-5p was significantly decreased in breast cancer tissues and Adriamycin-resistant breast cancer cells (MDA-MB-231/ADR, MCF-7/ADR). CCK-8, colony formation, wound healing, Transwell invasion, and flow cytometric profiles were examined to determine the influence of miR-129-5p on Adriamycin-resistant breast cancer in vitro. The upregulation of miR-129-5p decreased the IC50 concentration of Adriamycin and invasion and promoted the apoptosis of MDA-MB-231/ADR cells in the presence of Adriamycin, whereas the upregulation of Sex-Determining Region Y-Box 2 (SOX2) reversed these effects. A luciferase reporter assay confirmed the binding of miR-129-5p to the 3'UTR of SOX2. Collectively, it was suggested that miR-129-5p suppresses Adriamycin resistance in breast cancer by directly targeting SOX2.