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1.
Food Funct ; 10(8): 4725-4738, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31304955

RESUMO

Antrodia camphorata is a well-known traditional Chinese mushroom used as a functional food and nutraceutical in Taiwan and China. The aim of this study was to explore the protective effects and mechanism(s) of the ethyl acetate crude extract of A. camphorata (EtOAc-AC) and its active constituent ergostatrien-7,9(11),22-trien-3ß-ol (EK100) in an acute ischemic stroke (AIS) murine model. Treating mice with induced AIS injury by using EtOAc-AC (0.3-0.6 g kg-1, p.o.) and EK100 (60 and 120 mg kg-1, p.o.) 2 h after AIS induction significantly increased the tracking distance and reduced brain infarction. Both EtOAc-AC and EK-100 reduced the expression levels of p65NF-κB and caspase 3 near the peri-infarct cortex and promoted the expression of neurogenesis-associated protein doublecortin (DCX) near the hippocampus, accompanied by glycogen synthase kinase 3 (GSK-3) inhibition and ß-catenin upregulation. Signaling pathway analysis revealed that the advantageous effects of EtOAc-AC and EK-100 involved triggering the activation of PI3K/Akt and inhibition of GSK-3. Our findings suggest that EtOAc-AC and its active constituent EK100 display anti-inflammatory and anti-apoptotic activities. Both EtOAc-AC and EK100 reduce ischemic brain injury by decreasing p65NF-κB and caspase 3 expression, and they promote neurogenesis (DCX) and neuroprotection (Bcl2) by activating the PI3k/Akt-associated GSK3 inhibition and ß-catenin activation.


Assuntos
Antrodia/química , Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Ergosterol/análogos & derivados , Neurogênese/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Apoptose/efeitos dos fármacos , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Caspase 3/genética , Caspase 3/metabolismo , Cateninas/genética , Cateninas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Ergosterol/administração & dosagem , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo
2.
Int J Mol Sci ; 20(12)2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208038

RESUMO

Hyperglycaemia and type 2 diabetes (T2D) are associated with impaired insulin secretion and/or insulin action. Since few studies have addressed the relation between DNA methylation patterns with elaborated surrogates of insulin secretion/sensitivity based on the intravenous glucose tolerance test (IVGTT), the aim of this study was to evaluate the association between DNA methylation and an insulin sensitivity index based on IVGTT (calculated insulin sensitivity index (CSi)) in peripheral white blood cells from 57 non-diabetic female volunteers. The CSi and acute insulin response (AIR) indexes, as well as the disposition index (DI = CSi × AIR), were estimated from abbreviated IVGTT in 49 apparently healthy Chilean women. Methylation levels were assessed using the Illumina Infinium Human Methylation 450k BeadChip. After a statistical probe filtering, the two top CpGs whose methylation was associated with CSi were cg04615668 and cg07263235, located in the catenin delta 2 (CTNND2) and lipoprotein lipase (LPL) genes, respectively. Both CpGs conjointly predicted insulin sensitivity status with an area under the curve of 0.90. Additionally, cg04615668 correlated with homeostasis model assessment insulin-sensitivity (HOMA-S) and AIR, whereas cg07263235 was associated with plasma creatinine and DI. These results add further insights into the epigenetic regulation of insulin sensitivity and associated complications, pointing the CTNND2 and LPL genes as potential underlying epigenetic biomarkers for future risk of insulin-related diseases.


Assuntos
Cateninas/genética , Metilação de DNA , Resistência à Insulina/genética , Insulina/metabolismo , Leucócitos/metabolismo , Lipase Lipoproteica/genética , Adulto , Fatores Etários , Biomarcadores , Ilhas de CpG , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Epigênese Genética , Feminino , Teste de Tolerância a Glucose , Humanos , Curva ROC , Fatores Sexuais , Transdução de Sinais , Adulto Jovem
3.
Dev Cell ; 49(1): 31-47.e9, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30853440

RESUMO

The mechanism of how organ shape emerges and specifies cell fate is not understood. Pancreatic duct and endocrine lineages arise in a spatially distinct domain from the acinar lineage. Whether these lineages are pre-determined or settle once these niches have been established remains unknown. Here, we reconcile these two apparently opposing models, demonstrating that pancreatic progenitors re-localize to establish the niche that will determine their ultimate fate. We identify a p120ctn-regulated mechanism for coordination of organ architecture and cellular fate mediated by differential E-cadherin based cell sorting. Reduced p120ctn expression is necessary and sufficient to re-localize a subset of progenitors to the peripheral tip domain, where they acquire an acinar fate. The same mechanism is used re-iteratively during endocrine specification, where it balances the choice between the alpha and beta cell fates. In conclusion, organ patterning is regulated by p120ctn-mediated cellular positioning, which precedes and determines pancreatic progenitor fate.


Assuntos
Padronização Corporal/genética , Cateninas/genética , Pâncreas/crescimento & desenvolvimento , Ductos Pancreáticos/crescimento & desenvolvimento , Animais , Caderinas/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Movimento Celular/genética , Desenvolvimento Embrionário/genética , Citometria de Fluxo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Ilhotas Pancreáticas/crescimento & desenvolvimento , Ilhotas Pancreáticas/metabolismo , Camundongos , Pâncreas/metabolismo , Receptores Notch/genética , Transdução de Sinais/genética , Células-Tronco/metabolismo
4.
Mol Med Rep ; 19(1): 541-548, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30431117

RESUMO

At present, the mechanisms underlying intracranial aneurysm (IA) development remain unclear; however, hemodynamics is considered a crucial factor in the induction of IA. To elucidate the association between hemodynamics and endothelial cell (EC) functions, a modified T chamber system was designed to simulate the adjustable hemodynamic conditions of an artery bifurcation. Normal human umbilical vein ECs (HUVECs) and HUVECs with P120 catenin (P120ctn) knockdown were cultured on coverslips and placed in the chamber. A flow rate of 250 or 500 ml/min impinged on the cell layer. Subsequently, the expression levels of P120ctn and other proteins, and EC morphological alterations, were examined. In normal HUVECs, after 3 h under a flow rate of 500 ml/min, the expression levels of P120ctn, vascular endothelial (VE)­Cadherin, Kaiso and α­catenin were decreased, whereas matrix metalloproteinase­2 (MMP­2) was increased. In HUVECs with P120ctn knockdown, the period during which ECs adhered to the coverslip was reduced to 1 h under a flow rate of 500 ml/min. In addition, the expression levels of VE­Cadherin, Kaiso and α­catenin in ECs were decreased, whereas those of MMP­2 were increased after 1 h; more prominent alterations were detected under a 500 ml/min flow rate compared with a 250 ml/min flow rate. Adherens junctions (AJs) are critical to the maintenance of normal morphology and EC functioning in the vascular wall, and P120ctn is an important regulator of AJs. Loss of P120ctn may be induced by hemodynamic alterations. In response to changes in hemodynamic conditions, a loss of P120ctn may aggravate AJs between ECs, thus inducing inflammation in the vascular wall. Clinically, hemodynamic alterations may result in a loss of P120ctn and endothelial injury; therefore, P120ctn may have a critical role in inducing intracranial aneurysms.


Assuntos
Junções Aderentes/genética , Cateninas/genética , Células Endoteliais/patologia , Proteína p120 Ativadora de GTPase/genética , Caderinas/genética , Catequina/genética , Linhagem Celular , Hemodinâmica/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Aneurisma Intracraniano/genética , Aneurisma Intracraniano/patologia , Metaloproteinase 2 da Matriz/genética , Fatores de Transcrição/genética
5.
Proc Natl Acad Sci U S A ; 116(2): 546-555, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30584103

RESUMO

SENCR is a human-specific, vascular cell-enriched long-noncoding RNA (lncRNA) that regulates vascular smooth muscle cell and endothelial cell (EC) phenotypes. The underlying mechanisms of action of SENCR in these and other cell types is unknown. Here, levels of SENCR RNA are shown to be elevated in several differentiated human EC lineages subjected to laminar shear stress. Increases in SENCR RNA are also observed in the laminar shear stress region of the adult aorta of humanized SENCR-expressing mice, but not in disturbed shear stress regions. SENCR loss-of-function studies disclose perturbations in EC membrane integrity resulting in increased EC permeability. Biotinylated RNA pull-down and mass spectrometry establish an abundant SENCR-binding protein, cytoskeletal-associated protein 4 (CKAP4); this ribonucleoprotein complex was further confirmed in an RNA immunoprecipitation experiment using an antibody to CKAP4. Structure-function studies demonstrate a noncanonical RNA-binding domain in CKAP4 that binds SENCR Upon SENCR knockdown, increasing levels of CKAP4 protein are detected in the EC surface fraction. Furthermore, an interaction between CKAP4 and CDH5 is enhanced in SENCR-depleted EC. This heightened association appears to destabilize the CDH5/CTNND1 complex and augment CDH5 internalization, resulting in impaired adherens junctions. These findings support SENCR as a flow-responsive lncRNA that promotes EC adherens junction integrity through physical association with CKAP4, thereby stabilizing cell membrane-bound CDH5.


Assuntos
Junções Aderentes/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Proteínas de Membrana/metabolismo , RNA Longo não Codificante/metabolismo , Junções Aderentes/genética , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Cateninas/genética , Cateninas/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Proteínas de Membrana/genética , Domínios Proteicos , RNA Longo não Codificante/genética , Resistência ao Cisalhamento/fisiologia
6.
Biol Res ; 51(1): 31, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30180910

RESUMO

BACKGROUND: miR-214 was demonstrated to be upregulated in models of renal disease and promoted fibrosis in renal injury independent of TGF-ß signaling in vivo. However, the detailed role of miR-214 in acute kidney injury (AKI) and its underlying mechanism are still largely unknown. METHODS: In this study, an I/R-induced rat AKI model and a hypoxia-induced NRK-52E cell model were used to study AKI. The concentrations of kidney injury markers serum creatinine, blood urea nitrogen, and kidney injury molecule-1 were measured. The expressions of miR-214, tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, were detected by RT-qPCR. The protein levels of Bcl-2, Bax, Dickkopf-related protein 3, ß-catenin, c-myc, and cyclinD1 were determined by western blot. Cell apoptosis and caspase 3 activity were evaluated by flow cytometry analysis and caspase 3 activity assay, respectively. Luciferase reporter assay was used to confirm the interaction between miR-214 and Dkk3. RESULTS: miR-214 expression was induced in ischemia-reperfusion (I/R)-induced AKI rat and hypoxic incubation of NRK-52E cells. Overexpression of miR-214 alleviated hypoxia-induced NRK-52E cell apoptosis while inhibition of miR-214 expression exerted the opposite effect. Dkk3 was identified as a target of miR-214. Anti-miR-214 abolished the inhibitory effects of DKK3 knockdown on hypoxia-induced NRK-52E cell apoptosis by inactivation of Wnt/ß-catenin signaling. Moreover, miR-214 ameliorated AKI in vivo by inhibiting apoptosis and fibrosis through targeting Dkk3 and activating Wnt/ß-catenin pathway. CONCLUSION: miR-214 ameliorates AKI by inhibiting apoptosis through targeting Dkk3 and activating Wnt/ß-catenin signaling pathway, offering the possibility of miR-214 in the therapy of ischemic AKI.


Assuntos
Lesão Renal Aguda/metabolismo , Cateninas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , MicroRNAs/metabolismo , Via de Sinalização Wnt/genética , Lesão Renal Aguda/induzido quimicamente , Animais , Cateninas/genética , Proliferação de Células , Quimiocinas , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley
7.
J Cancer Res Ther ; 14(Supplement): S680-S687, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30249887

RESUMO

Aim of Study: Recent studies have suggested neprilysin (NEP) play a key role in cigarette smoke-induced nonsmall-cell lung carcinoma; however, the detailed mechanism was still unclear. Here, we employed in vitro human bronchial epithelial BEAS-2B cells to investigate whether and how NEP involved in cigarette smoke condensate (CSC)-induced cancer occurrence. Materials and Methods: In vitro MTT and transwell assay was applied. Live cell imaging and staining were also employed. Results: In vitro data showed that CSC could increase BEAS-2B cell migration while NEP shRNA could block CSC-induced BEAS-2B cell hypermigration. By biotination and live cell staining, we found that after CSC treatment, cell surface NEP was increased while internalization trafficking was shifted from late endosome/lysosome pathway to recycling pathway. Finally, we found that surface NEP could bind to p120 catenin (p120ctn) for lysosome destination turnover while CSC treatment could change p120ctn membrane/cytosome distribution. Loss of p120ctn will subsequently change NEP trafficking and finally, increase its membrane distribution with a phenocopy manner as CSC. Conclusion: These data indicated under CSC treatment; losing of membrane p120ctn could upregulate surface NEP protein level and thus facilitate BEAS-2B cell migration.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Cateninas/genética , Movimento Celular/genética , Neprilisina/genética , Brônquios/efeitos dos fármacos , Brônquios/patologia , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Lisossomos/efeitos dos fármacos , RNA Interferente Pequeno/genética , Fumar/efeitos adversos , Tabaco/toxicidade , Produtos do Tabaco/toxicidade
8.
Biomed Pharmacother ; 106: 483-490, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29990836

RESUMO

MicroRNAs (miRNAs) are solid factors involved in the initiation and progression of hepatocellular carcinoma (HCC). Recently, miR-298 is recognized as a cancer-associated miRNA in breast, gastric and ovarian cancer. However, the functional role of miR-298 and its underlying mechanism are rarely reported in HCC. Herein, we found that the expression of miR-298 was down-regulated in HCC tissues and cell lines. The in vitro experiments showed that miR-298 overexpression inhibited cell proliferation, migration and invasion, and induced G1 arrest and apoptosis of HCC cells. miR-298 knockdown exerted an opposite effect on these cellular behaviors of HCC cells. Moreover, miR-298 restoration suppressed HCC tumor growth and metastasis in vivo. Additionally, catenin delta 1 (CTNND1) was demonstrated to be a direct target of miR-298 in HCC cells. CTNND1 knockdown led to similar effects with miR-298 overexpression on HCC cell proliferation, cell cycle progression, apoptosis and mobility. CTNND1 restoration reversed miR-298-induced inhibitory effects on HCC cells. Mechanistically, both miR-298 overexpression and CTNND1 knockdown repressed Wnt/ß-catenin signaling and resulted in reduced expression of ß-catenin, WNT11, Cyclin D1 and MMP7 in HCCLM3 cells. While, CTNND1 restoration abolished miR-298-induced inactivation of Wnt/ß-catenin signaling. In conclusion, our findings provide the first evidence that miR-298 suppresses HCC progression at least partially by targeting CTNND1-mediated Wnt/ß-catenin signaling. MiR-298 may be a target for new therapies in HCC patients.


Assuntos
Carcinoma Hepatocelular/metabolismo , Cateninas/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Via de Sinalização Wnt , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/secundário , Cateninas/genética , Movimento Celular , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Progressão da Doença , Pontos de Checagem da Fase G1 do Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , MicroRNAs/genética , Invasividade Neoplásica , Fatores de Tempo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
9.
Cell Physiol Biochem ; 48(1): 237-250, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30007960

RESUMO

BACKGROUND/AIMS: Thermal injury causes pulmonary edema and can lead to death. Intercellular junctions are composed of adhesive (p120ctn, E-cadherin, α-catenin and ß-catenin) and compact (occludin and ZO-1) junctions. Heat deteriorates intercellular junctions and increases cell gaps to ultimately induce pulmonary edema, but the underlying mechanism remains elusive. METHODS: Mouse lung epithelial (MLE-12) cells pre-treated with the c-Src inhibitor PP2, p120ctn catenin (p120ctn) small interfering RNA and p120ctn catenin (p120ctn) complementary DNA were subjected to heat treatment. Western blotting and real-time polymerase chain reaction assays were used to evaluate junction protein expression changes after heat treatment, and co-immunoprecipitation was used to test the binding state of junction proteins. In addition, hematoxylin and eosin staining and immunohistochemistry were used to evaluate changes in junction protein expression and lung injury in a Wistar rat model of thermal inhalation injury. RESULTS: Heat increased cell permeability; induced ZO-1, occludin, α-catenin and ß-catenin degradation; and decreased E-cadherin distribution in cell membranes. Heat also activated c-Src and decreased both p120ctn expression levels and occludin and ZO-1 association. c-Src inhibitor (PP2) treatment and p120ctn overexpression reversed these effects and attenuated lung injury in vivo. CONCLUSION: Heat induces junction protein degradation and dissociation to increase membrane permeability and cause lung edema via c-Src kinase activation and p120ctn expression downregulation.


Assuntos
Cateninas/metabolismo , Quinases da Família src/metabolismo , Animais , Caderinas/metabolismo , Cateninas/antagonistas & inibidores , Cateninas/genética , Linhagem Celular , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Regulação para Baixo , Expressão Gênica/efeitos dos fármacos , Temperatura Alta , Pulmão/citologia , Pulmão/metabolismo , Masculino , Ocludina/metabolismo , Proteólise , Pirimidinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína da Zônula de Oclusão-1/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/genética
10.
J Cell Physiol ; 234(1): 427-432, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29923340

RESUMO

p120-catenin (p120) is an important regulator in the function and stability of E-cadherin. However, the role of p120 in the epidermis is unclear. Previous studies have shown that globally knockout of p120 caused increased epidermal proliferation but little changes in epidermal differentiation and permeability. In the present study, we generated a conditional knockout mouse model and examined epidermal proliferation, differentiation and permeability. The results showed that conditional knockout of p120 in the epidermis caused not only increased epidermal proliferation but also decreased epidermal differentiation and increased permeability. These data suggest that p120 is required for suppressing epidermal proliferation, promoting epidermal differentiation and maintaining permeability barrier function of the epidermis.


Assuntos
Cateninas/genética , Diferenciação Celular/genética , Epiderme/crescimento & desenvolvimento , Animais , Caderinas/genética , Permeabilidade da Membrana Celular/genética , Proliferação de Células/genética , Células Epidérmicas/metabolismo , Células Epidérmicas/patologia , Epiderme/metabolismo , Epiderme/patologia , Humanos , Camundongos , Camundongos Knockout
11.
Am J Hum Genet ; 102(6): 1143-1157, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29805042

RESUMO

Non-syndromic cleft lip with or without cleft palate (NS-CL/P) is one of the most common human birth defects and is generally considered a complex trait. Despite numerous loci identified by genome-wide association studies, the effect sizes of common variants are relatively small, with much of the presumed genetic contribution remaining elusive. We report exome-sequencing results in 209 people from 72 multi-affected families with pedigree structures consistent with autosomal-dominant inheritance and variable penetrance. Herein, pathogenic variants are described in four genes encoding components of the p120-catenin complex (CTNND1, PLEKHA7, PLEKHA5) and an epithelial splicing regulator (ESRP2), in addition to the known CL/P-associated gene, CDH1, which encodes E-cadherin. The findings were also validated in a second cohort of 497 people with NS-CL/P, comprising small families and singletons with pathogenic variants in these genes identified in 14% of multi-affected families and 2% of the replication cohort of smaller families. Enriched expression of each gene/protein in human and mouse embryonic oro-palatal epithelia, demonstration of functional impact of CTNND1 and ESRP2 variants, and recapitulation of the CL/P spectrum in Ctnnd1 knockout mice support a causative role in CL/P pathogenesis. These data show that primary defects in regulators of epithelial cell adhesion are the most significant contributors to NS-CL/P identified to date and that inherited and de novo single gene variants explain a substantial proportion of NS-CL/P.


Assuntos
Caderinas/genética , Cateninas/genética , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Mutação/genética , Alelos , Sequência de Aminoácidos , Animais , Biotinilação , Epitélio/metabolismo , Epitélio/patologia , Feminino , Deleção de Genes , Humanos , Lactente , Recém-Nascido , Masculino , Camundongos , Palato/patologia , Linhagem , Síndrome , Sequenciamento Completo do Exoma
12.
Mol Cells ; 41(4): 320-330, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29629558

RESUMO

δ-Catenin, a member of the p120-catenin subfamily of armadillo proteins, reportedly increases during the late stage of prostate cancer. Our previous study demonstrates that δ-catenin increases the stability of EGFR in prostate cancer cell lines. However, the molecular mechanism behind δ-catenin-mediated enhanced stability of EGFR was not explored. In this study, we hypothesized that δ-catenin enhances the protein stability of EGFR by inhibiting its lysosomal degradation that is mediated by c-casitas b-lineage lymphoma (c-Cbl), a RING domain E3 ligase. c-Cbl monoubiquitinates EGFR and thus facilitates its internalization, followed by lysosomal degradation. We observed that δ-catenin plays a key role in EGFR stability and downstream signaling. δ-Catenin competes with c-Cbl for EGFR binding, which results in a reduction of binding between c-Cbl and EGFR and thus decreases the ubiquitination of EGFR. This in turn increases the expression of membrane bound EGFR and enhances EGFR/Erk1/2 signaling. Our findings add a new perspective on the role of δ-catenin in enhancing EGFR/Erk1/2 signaling-mediated prostate cancer.


Assuntos
Cateninas/metabolismo , Receptores ErbB/metabolismo , Sistema de Sinalização das MAP Quinases , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Cateninas/biossíntese , Cateninas/genética , Linhagem Celular Tumoral , Receptores ErbB/biossíntese , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Humanos , Masculino , Estabilidade Proteica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Transfecção , Ubiquitinação
13.
Eur J Hum Genet ; 26(2): 210-219, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29348693

RESUMO

Blepharocheilodontic syndrome (BCDS) consists of lagophthalmia, ectropion of the lower eyelids, distichiasis, euryblepharon, cleft lip/palate and dental anomalies and has autosomal dominant inheritance with variable expression. We identified heterozygous variants in two genes of the cadherin-catenin complex, CDH1, encoding E-cadherin, and CTNND1, encoding p120 catenin delta1 in 15 of 17 BCDS index patients, as was recently described in a different publication. CDH1 plays an essential role in epithelial cell adherence; CTNND1 binds to CDH1 and controls the stability of the complex. Functional experiments in zebrafish and human cells showed that the CDH1 variants impair the cell adhesion function of the cadherin-catenin complex in a dominant-negative manner. Variants in CDH1 have been linked to familial hereditary diffuse gastric cancer and invasive lobular breast cancer; however, no cases of gastric or breast cancer have been reported in our BCDS cases. Functional experiments reported here indicated the BCDS variants comprise a distinct class of CDH1 variants. Altogether, we identified the genetic cause of BCDS enabling DNA diagnostics and counseling, in addition we describe a novel class of dominant negative CDH1 variants.


Assuntos
Antígenos CD/genética , Caderinas/genética , Cateninas/genética , Fenda Labial/genética , Fissura Palatina/genética , Ectrópio/genética , Mutação , Anormalidades Dentárias/genética , Adolescente , Adulto , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Cateninas/metabolismo , Adesão Celular , Criança , Pré-Escolar , Fenda Labial/patologia , Fissura Palatina/patologia , Ectrópio/patologia , Feminino , Humanos , Células MCF-7 , Masculino , Ligação Proteica , Anormalidades Dentárias/patologia , Peixe-Zebra
14.
Oncol Rep ; 39(2): 809-817, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29251319

RESUMO

δ-Catenin coded by gene CTNND2 has been found to be overexpressed in various types of cancers, including prostate, breast, lung and ovarian cancers. However, the function of δ-catenin in lung carcinoma remains largely unknown. In the present study, we revealed that δ-catenin acts as an oncogene promoting the malignancy of lung adenocarcinoma. When δ-catenin proteins of Lewis lung cells were depleted by knocking out Ctnnd2 via CRISPR/Cas9 technology, the cells lost the tumorigenic and metastatic abilities in vivo. Consistently, overexpression of Ctnnd2 enhances the subcutaneous tumorigenesis and distant metastasis of Lewis lung cells in vivo. However, δ-catenin promotes cell proliferation and cell cycle progression of Lewis lung cells. Mechanistically, δ-catenin enhances G1-S phase transition in cooperation with canonical Wnt signaling in Lewis lung cells. Moreover, δ-catenin promotes oncosphere formation of lung adenocarcinoma cells and is associated with the expression of cancer stem cell markers, which indicates δ-catenin enhances colonization and invasion via cancer stem cell maintenance. Taken together, our data suggest that δ-catenin may serve an important role in the malignancy of lung adenocarcinoma through activating canonical Wnt signaling and cancer stem cell maintenance. Our research indicates that δ-catenin can be a new potential target for the treatment of lung adenocarcinoma.


Assuntos
Adenocarcinoma/patologia , Cateninas/genética , Cateninas/metabolismo , Neoplasias Pulmonares/patologia , Células A549 , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Animais , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Técnicas de Inativação de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Metástase Neoplásica , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Via de Sinalização Wnt
15.
Appl Immunohistochem Mol Morphol ; 26(1): 64-70, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27299185

RESUMO

BACKGROUND: Previous research connects p120-catenin (p120ctn) with epidermal growth factor receptor (EGFR) signaling pathways, which presents a potential role for p120ctn in EGFR tyrosine kinase inhibitor (EGFR-TKIs) resistance. However, a direct correlation between the expression pattern of p120ctn in solid tumors and the therapeutic effect of EGFR-TKIs has not yet been demonstrated. METHODS AND RESULTS: In this study, the expression pattern of p120ctn was examined in patients with the EGFR gene mutation in lung adenocarcinoma, and p120ctn was found to have different patterns of expression even in the same mutation type. The therapeutic effect of EGFR-TKIs was investigated in these patients, and patients with an abnormal expression of p120ctn were found to be more likely to have drug resistance. A gefitinib-resistant lung cancer cell line was established and alterations in the p120ctn expression pattern were also observed in vitro. CONCLUSIONS: Therefore, this study demonstrates that the expression pattern of p120ctn is associated with acquired resistance to EGFR-TKIs in lung cancer, providing information toward addressing the problem of drug resistance in patients with non-small cell lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Cateninas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Proteínas Tirosina Quinases/antagonistas & inibidores , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Cateninas/metabolismo , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Receptores ErbB/genética , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Mutação , Transcriptoma
16.
Int J Mol Sci ; 18(12)2017 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-29207493

RESUMO

Glycoprotein 90K (also known as LGALS3BP or Mac-2BP) is a tumor-associated protein, and high 90K levels are associated with poor prognosis in some cancers. To clarify the role of 90K as an indicator for poor prognosis and metastasis in epithelial cancers, the present study investigated the effect of 90K on an adherens junctional protein, E-cadherin, which is frequently absent or downregulated in human epithelial cancers. Treatment of certain cancer cells with 90K significantly reduced E-cadherin levels in a cell-population-dependent manner, and these cells showed decreases in cell adhesion and increases in invasive cell motility. Mechanistically, 90K-induced E-cadherin downregulation occurred via ubiquitination-mediated proteasomal degradation. 90K interacted with the E-cadherin-p120-catenin complex and induced its dissociation, altering the phosphorylation status of p120-catenin, whereas it did not associate with ß-catenin. In subconfluent cells, 90K decreased membrane-localized p120-catenin and the membrane fraction of the p120-catenin. Particularly, 90K-induced E-cadherin downregulation was diminished in p120-catenin knocked-down cells. Taken together, 90K upregulation promotes the dissociation of the E-cadherin-p120-catenin complex, leading to E-cadherin proteasomal degradation, and thereby destabilizing adherens junctions in less confluent tumor cells. Our results provide a potential mechanism to explain the poor prognosis of cancer patients with high serum 90K levels.


Assuntos
Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Proteínas de Transporte/metabolismo , Cateninas/metabolismo , Glicoproteínas/metabolismo , Neoplasias/metabolismo , Antígenos CD , Células CACO-2 , Cateninas/genética , Adesão Celular , Contagem de Células , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Células MCF-7 , Masculino , Invasividade Neoplásica , Fosforilação , Prognóstico , Proteólise
17.
BMC Cancer ; 17(1): 832, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-29216867

RESUMO

BACKGROUND: Despite recent advances in the diagnosis and treatment of breast cancer, metastasis remains the main cause of death. Since migration of tumor cells is considered a prerequisite for tumor cell invasion and metastasis, a pressing goal in tumor biology has been to elucidate factors regulating their migratory activity. Protein kinase C alpha (PKCα) is a serine-threonine protein kinase implicated in cancer metastasis and associated with poor prognosis in breast cancer patients. In this study, we set out to define the signaling axis mediated by PKCα to promote breast cancer cell migration. METHODS: Oncomine™ overexpression analysis was used to probe for PRKCA (PKCα) and FOXC2 expression in mRNA datasets. The heat map of PRKCA, FOXC2, and CTNND1 were obtained from the UC Santa Cruz platform. Survival data were obtained by PROGgene and available at http://www.compbio.iupui.edu/proggene . Markers for EMT and adherens junction were assessed by Western blotting and quantitative polymerase chain reaction. Effects of PKCα and FOXC2 on migration and invasion were assessed in vitro by transwell migration and invasion assays respectively. Cellular localization of E-cadherin and p120-catenin was determined by immunofluorescent staining. Promoter activity of p120-catenin was determined by dual luciferase assay using a previously validated p120-catenin reporter construct. Interaction between FOXC2 and p120-catenin promoter was verified by chromatin immunoprecipitation assay. RESULTS: We determined that PKCα expression is necessary to maintain the migratory and invasive phenotype of both endocrine resistant and triple negative breast cancer cell lines. FOXC2 acts as a transcriptional repressor downstream of PKCα, and represses p120-catenin expression. Consequently, loss of p120-catenin leads to destabilization of E-cadherin at the adherens junction. Inhibition of either PKCα or FOXC2 is sufficient to rescue p120-catenin expression and trigger relocalization of p120-catenin and E-cadherin to the cell membrane, resulting in reduced tumor cell migration and invasion. CONCLUSIONS: Taken together, these results suggest that breast cancer metastasis may partially be controlled through PKCα/FOXC2-dependent repression of p120-catenin and highlight the potential for PKCα signal transduction networks to be targeted for the treatment of endocrine resistant and triple negative breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Cateninas/metabolismo , Movimento Celular/genética , Fatores de Transcrição Forkhead/metabolismo , Proteína Quinase C-alfa/metabolismo , Neoplasias da Mama/genética , Cateninas/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Feminino , Fatores de Transcrição Forkhead/análise , Fatores de Transcrição Forkhead/genética , Perfilação da Expressão Gênica , Humanos , Invasividade Neoplásica/genética , Proteína Quinase C-alfa/análise , Proteína Quinase C-alfa/genética , Transdução de Sinais/genética
18.
Neurology ; 89(23): 2341-2350, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29127138

RESUMO

OBJECTIVE: To identify the causative gene in a large Dutch family with familial cortical myoclonic tremor and epilepsy (FCMTE). METHODS: We performed exome sequencing for 3 patients of our FCMTE family. Next, we performed knock-down (shRNA) and rescue experiments by overexpressing wild-type and mutant human δ-catenin (CTNND2) proteins in cortical mouse neurons and compared the results with morphologic abnormalities in the postmortem FCMTE brain. RESULTS: We identified a missense mutation, p.Glu1044Lys, in the CTNND2 gene that cosegregated with the FCMTE phenotype. The knock-down of Ctnnd2 in cultured cortical mouse neurons revealed increased neurite outgrowth that was rescued by overexpression of wild-type, but not mutant, CTNND2 and was reminiscent of the morphologic abnormalities observed in cerebellar Purkinje cells from patients with FCMTE. CONCLUSIONS: We propose CTNND2 as the causal gene in FCMTE3. Functional testing of the mutant protein revealed abnormal neuronal sprouting, consistent with the abnormal cerebellar Purkinje cell morphology in patients with FCMTE.


Assuntos
Cateninas/genética , Epilepsias Mioclônicas/genética , Tremor Essencial/genética , Mutação de Sentido Incorreto/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Exoma , Família , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Neurônios/metabolismo , Neurônios/patologia , Linhagem , Células de Purkinje/patologia , RNA Interferente Pequeno , Adulto Jovem
19.
J Clin Invest ; 127(12): 4462-4476, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29130932

RESUMO

p120-Catenin (p120) functions as a tumor suppressor in intestinal cancer, but the mechanism is unclear. Here, using conditional p120 knockout in Apc-sensitized mouse models of intestinal cancer, we have identified p120 as an "obligatory" haploinsufficient tumor suppressor. Whereas monoallelic loss of p120 was associated with a significant increase in tumor multiplicity, loss of both alleles was never observed in tumors from these mice. Moreover, forced ablation of the second allele did not further enhance tumorigenesis, but instead induced synthetic lethality in combination with Apc loss of heterozygosity. In tumor-derived organoid cultures, elimination of both p120 alleles resulted in caspase-3-dependent apoptosis that was blocked by inhibition of Rho kinase (ROCK). With ROCK inhibition, however, p120-ablated organoids exhibited a branching phenotype and a substantial increase in cell proliferation. Access to data from Sleeping Beauty mutagenesis screens afforded an opportunity to directly assess the tumorigenic impact of p120 haploinsufficiency relative to other candidate drivers. Remarkably, p120 ranked third among the 919 drivers identified. Cofactors α-catenin and epithelial cadherin (E-cadherin) were also among the highest scoring candidates, indicating a mechanism at the level of the intact complex that may play an important role at very early stages of of intestinal tumorigenesis while simultaneously restricting outright loss via synthetic lethality.


Assuntos
Proteína da Polipose Adenomatosa do Colo , Cateninas , Haploinsuficiência , Neoplasias Intestinais , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Animais , Cateninas/genética , Cateninas/metabolismo , Neoplasias Intestinais/genética , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Camundongos , Camundongos Knockout , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
20.
Eur J Cell Biol ; 96(7): 695-704, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28818340

RESUMO

Lipopolysaccharide (LPS) is known to mediate angiogenic effects in endothelial cells. The underlying mechanisms, however, remain largely unknown. In this study, we showed that LPS induced high motility group box protein 1 (HMGB1) secretion in human pulmonary microvascular endothelial cells (HPMECs). Knockdown and overexpression of HMGB1 by adenoviral vectors effectively inhibited and promoted LPS-induced HPMEC migration and capillary-like tube formation, respectively. On the other hand, HMGB1 exerted an inhibitory effect on LPS-suppressed expression of platelet-endothelial cell adhesion molecule (CD31) and p120 catenin (p120); HMGB1 knockdown reversed this effect. These results suggest a functional synergy between LPS and HMGB1 in angiogenesis. Mechanistically, physical interaction of LPS with HMGB1 mediated dissociation of p120, ß-catenin, and γ-catenin from vascular endothelial cadherin (VE-cadherin), but without affecting VE-cadherin expression. The synergistic effect of LPS and HMGB1 was closely associated with ERK/P38/Src signaling pathway, as evidenced by the reduced degree of migration and capillary-like tube formation in HPMECs treated with signaling pathway inhibitor. Collectively, our study shows a novel mechanism whereby LPS and HMGB1 synergistically regulate the angiogenic behavior of endothelial cells.


Assuntos
Células Endoteliais/metabolismo , Proteína HMGB1/genética , Lipopolissacarídeos/metabolismo , Neovascularização Fisiológica/genética , Antígenos CD/genética , Caderinas/genética , Cateninas/genética , Cateninas/metabolismo , Movimento Celular/genética , Regulação da Expressão Gênica , Humanos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Transdução de Sinais
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