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1.
Proc Natl Acad Sci U S A ; 116(28): 14039-14048, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31239343

RESUMO

Most normal and tumor cells are protected from tumor necrosis factor α (TNFα)-induced apoptosis. Here, we identify the MAP3 kinase tumor progression locus-2 (TPL2) as a player contributing to the protection of a subset of tumor cell lines. The combination of TPL2 knockdown and TNFα gives rise to a synthetic lethality phenotype via receptor-interacting serine/threonine-protein kinase 1 (RIPK1)-dependent and -independent mechanisms. Whereas wild-type TPL2 rescues the phenotype, its kinase-dead mutant does not. Comparison of the molecular events initiated by small interfering RNA for TPL2 (siTPL2) ± TNFα in treatment-sensitive and -resistant lines revealed that the activation of caspase-8, downstream of miR-21-5p and cFLIP, is the dominant TPL2-dependent event. More important, comparison of the gene expression profiles of all of the tested cell lines results in the clustering of sensitive and resistant lines into distinct groups, providing proof of principle for the feasibility of generating a predictive tool for treatment sensitivity.


Assuntos
Carcinoma/genética , Inibidores de Caspase/farmacologia , MAP Quinase Quinase Quinases/genética , Proteínas Proto-Oncogênicas/genética , Fator de Necrose Tumoral alfa/genética , Apoptose/genética , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Caspase 8/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , Macrófagos/metabolismo , MicroRNAs/genética , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , RNA Interferente Pequeno/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais , Mutações Sintéticas Letais/genética
2.
J Biol Chem ; 290(10): 6130-40, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25572395

RESUMO

Recent studies using ClipR-59 knock-out mice implicated this protein in the regulation of muscle function. In this report, we have examined the role of ClipR-59 in muscle differentiation and found that ClipR-59 knockdown in C2C12 cells suppressed myoblast fusion. To elucidate the molecular mechanism whereby ClipR-59 regulates myoblast fusion, we carried out a yeast two-hybrid screen using ClipR-59 as the bait and identified Elmo2, a member of the Engulfment and cell motility protein family, as a novel ClipR-59-associated protein. We showed that the interaction between ClipR-59 and Elmo2 was mediated by the atypical PH domain of Elmo2 and the Glu-Pro-rich domain of ClipR-59 and regulated by Rho-GTPase. We have examined the impact of ClipR-59 on Elmo2 downstream signaling and found that interaction of ClipR-59 with Elmo2 enhanced Rac1 activation. Collectively, our studies demonstrate that formation of an Elmo2·ClipR-59 complex plays an important role in myoblast fusion.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Desenvolvimento Muscular/genética , Mioblastos/citologia , Animais , Diferenciação Celular , Humanos , Camundongos , Camundongos Knockout , Complexos Multiproteicos/genética , Mioblastos/metabolismo , Neuropeptídeos/metabolismo , Estrutura Terciária de Proteína/genética , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo
3.
Biochem Biophys Res Commun ; 460(3): 709-14, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25824042

RESUMO

Recently, we identified Glut4 as a palmitoylated protein in adipocytes. To understand the role of Glut4 palmitoylation in Glut4 membrane trafficking, a process that is essential for maintenance of whole body glucose homeostasis, we have characterized Glut4 palmitoylation. We found that Glut4 is palmitoylated at Cys223 and Glut4 palmitoylation at Cys223 is essential for insulin dependent Glut4 membrane translocation as substitution of Cys223 with a serine residue in Glut4 (C223S Glut4) diminished Glut4 responsiveness to insulin in membrane translocation in both adipocytes and CHO-IR cells. We have examined C223S Glut4 subcellular localization and observed that it was absence from tubular-vesicle structure, where insulin responsive Glut4 vesicles were presented. Together, our studies uncover a novel mechanism under which Glut4 palmitoylation regulates Glut4 sorting to insulin responsive vesicles, thereby insulin-dependent Glut4 membrane translocation.


Assuntos
Transportador de Glucose Tipo 4/metabolismo , Lipoilação , Células 3T3-L1 , Animais , Membrana Celular/metabolismo , Transportador de Glucose Tipo 4/química , Camundongos , Transporte Proteico
4.
Proc Natl Acad Sci U S A ; 109(18): E1082-91, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22451924

RESUMO

To address the role of Tpl2, a MAP3K8 that regulates innate/adaptive immunity and inflammation, in intestinal tumorigenesis, we crossed a Tpl2 KO allele into the Apc(min/+) genetic background. Here, we show that Apc(min/+)/Tpl2(-/-) mice exhibit a fivefold increase in the number of intestinal adenomas. Bone marrow transplantation experiments revealed that the enhancement of polyposis was partially hematopoietic cell-driven. Consistent with this observation, Tpl2 ablation promoted intestinal inflammation. IL-10 levels and regulatory T-cell numbers were lower in the intestines of Tpl2(-/-) mice, independent of Apc and polyp status, suggesting that they were responsible for the initiation of the enhancement of tumorigenesis caused by the ablation of Tpl2. The low IL-10 levels correlated with defects in mTOR activation and Stat3 phosphorylation in Toll-like receptor-stimulated macrophages and with a defect in inducible regulatory T-cell generation and function. Both polyp numbers and inflammation increased progressively with time. The rate of increase of both, however, was more rapid in Apc(min/+)/Tpl2(-/-) mice, suggesting that the positive feedback initiated by inflammatory signals originating in developing polyps is more robust in these mice. This may be because these mice have a higher intestinal polyp burden as a result of the enhancement of tumor initiation.


Assuntos
Genes APC , Doenças Inflamatórias Intestinais/etiologia , Interleucina-10/biossíntese , Neoplasias Intestinais/etiologia , MAP Quinase Quinase Quinases/deficiência , Proteínas Proto-Oncogênicas/deficiência , Linfócitos T Reguladores/imunologia , Adenoma/etiologia , Adenoma/genética , Adenoma/imunologia , Animais , Transplante de Medula Óssea , Feminino , Expressão Gênica , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Neoplasias Intestinais/genética , Neoplasias Intestinais/imunologia , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Modelos Imunológicos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/imunologia
5.
J Biol Chem ; 288(15): 10902-13, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-23439647

RESUMO

Recent studies reveal that COP1 suppresses the expression of gluconeogenetic genes and prohibits hepatic glucose production. To get more insight into COP1 in hepatic cells, we examined the impact of COP1 on insulin-responsive genes and insulin signaling. We found that COP1 increased the responsiveness of insulin-modulated genes to insulin in that it promoted the expression of insulin-induced genes and inhibited that of insulin-suppressed genes and that COP1 enhanced insulin signaling as it promoted phosphorylation of Akt and ERK as well as tyrosine phosphorylation of IRß induced by insulin. To delineate the mechanism under which COP1 modulates insulin signaling, we examined the possibility that COP1 modulates the activity of PTP1B, the major insulin receptor tyrosine phosphatase. The results indicated that COP1 physically interacted with PTP1B and suppressed PTP1B phosphatase activity as well as the association of PTP1B with IRß. We suggest that COP1 is a positive regulator of hepatic insulin signaling.


Assuntos
Insulina/metabolismo , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Nucleares/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Ativação Enzimática/fisiologia , Células Hep G2 , Humanos , Insulina/genética , Camundongos , Proteínas Nucleares/genética , Fosforilação/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Ubiquitina-Proteína Ligases/genética
6.
J Biol Chem ; 287(32): 26890-900, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22689584

RESUMO

ClipR-59 is a membrane-associated protein and has been implicated in membrane signaling and vesicle trafficking. Recently, we have identified ClipR-59 as an Akt-interacting protein, and we have found that, by interacting with Akt, ClipR-59 modulates Akt subcellular compartmentalization and Akt substrate AS160 phosphorylation, thereby promoting Glut4 membrane translocation. Here, we have further investigated the regulatory effects of ClipR-59 on AS160 phosphorylation and subsequent adipocyte glucose transport. Our data showed that ClipR-59 interacted with AS160, which was mediated by the ankyrin repeats of ClipR-59 and regulated by insulin signaling. Moreover, the data also demonstrated that the interaction of ClipR-59 with AS160 was required for ClipR-59 to modulate Glut4 membrane translocation as ΔANK-ClipR-59, an AS160 interaction-defective mutant, failed to promote AS160 phosphorylation, Glut4 membrane translocation, and glucose transport induced by insulin in 3T3-L1 adipocytes. Because ClipR-59 also interacts with Akt and enhances the interaction between Akt and AS160, we suggest that ClipR-59 functions as a scaffold protein to facilitate Akt-mediated AS160 phosphorylation, thereby regulating glucose transport.


Assuntos
Adipócitos/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Células 3T3 , Animais , Membrana Celular/metabolismo , Humanos , Camundongos , Fosforilação , Transporte Proteico , Transdução de Sinais , Regulação para Cima
7.
J Environ Radioact ; 246: 106848, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35219123

RESUMO

Uranium in coals is an environmental radionuclide with resource utilization value. To comprehensively understand the prevalence of uranium in Chinese coals, the concentration, spatial distribution, and modes of occurrence were analyzed based on the data acquired from 1326 coal samples. Chinese coals are relatively rich in uranium, with the arithmetic and weighted average concentrations of 3.08 and 2.38 mg/kg, respectively. The regions with high uranium enrichment in coals are Guizhou, Guangxi, Yunnan, Sichuan and Chongqing, which are mainly located in southwestern China. The uranium was more enriched in Late Permian coal and medium-to-high metamorphic coal. Organic matter is the main carrier of uranium in coals, followed by silicates and sulfides. The factors affecting uranium enrichment in coal at the national scale include magma intrusions, volcanic ash, seawater influence, low-temperature hydrothermal fluids, and paleoclimate. This paper provides a reference for further research on environmental management and resource utilization of uranium in Chinese coals.


Assuntos
Monitoramento de Radiação , Urânio , China , Carvão Mineral/análise
8.
Am J Physiol Lung Cell Mol Physiol ; 300(3): L486-97, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21186266

RESUMO

The serotonin transporter (SERT) and the platelet-derived growth factor receptor (PDGFR) have been implicated in both clinical and experimental pulmonary hypertension (PH) and the facilitation of pulmonary artery smooth muscle cell (PASMC) growth. To gain a better understanding of the possible relationship of these two cell surface molecules we have explored interactions between SERT and PDGFR. We have previously demonstrated that SERT transactivates PDGFRß in serotonin-stimulated PASMC proliferation. We now provide evidence for a role for SERT in PDGF-BB signaling and PASMC proliferation by using pharmacological inhibitors, genetic ablation, and construct overexpression of SERT. The results show that four tested SERT blockers dose dependently inhibit PDGF-stimulated human and bovine PASMC proliferation with comparable efficacy to that of PDGFR inhibitors, whereas 5-HT1B or 5-HT2A receptor inhibitors had no effect. Combinations of the SERT and PDGFR inhibitors led to synergistic/additive inhibition. Similarly, PDGF-induced PASMC proliferation was attenuated by small interfering RNA downregulation of SERT. Inhibition of SERT in PASMCs attenuated PDGF-induced phosphorylation of PDGFRß, Akt, and p38 but not Erk. Overexpression of SERT in HEK293 cells led to enhanced Akt phosphorylation by PDGF, which was blunted by a SERT PDZ motif mutant, indicating the mechanistic need for the PDZ motif of SERT in PDGF signaling. Furthermore, coimmunoprecipitation experiments showed that SERT and PDGFRß become physically associated upon PDGF stimulation. In total, the data show for the first time an important interactive relationship between SERT and the PDGFRß in the production of PASMC proliferation triggered by PDGF that may be important in PH.


Assuntos
Mitose/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Artéria Pulmonar/citologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Motivos de Aminoácidos , Animais , Becaplermina , Bovinos , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Mutação/genética , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/enzimologia , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-sis , RNA Interferente Pequeno/metabolismo , Ratos , Proteínas da Membrana Plasmática de Transporte de Serotonina/química , Relação Estrutura-Atividade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
Sci Total Environ ; 799: 149475, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34426324

RESUMO

Coal resource utilization and environmental protection is a critical global issue. This study aims to address the need for geochemical maps of harmful trace elements (HTEs) in Chinese coalfields and to extract scientific information from these maps. Based on data extracted from the Trace Elements in Coal of China database, geochemical maps of As, Cd, Cr, F, Hg, Ni, Pb, and Se in Chinese coalfields were generated, for the first time, using the ArcGIS platform. Differences in regional HTE concentrations were attributed to multiple factors, including the type of coal-forming environment, terrigenous debris, and groundwater effect. However, on a national scale, the spatial distribution pattern of HTEs in coal is affected by the abundance of elements in the earth's crust. Herein, the enrichment anomaly of HTEs in coal were found to be significantly correlated with fault locations, and hydrothermal fluid action was characterized as the primary causal factor. HTE abundance in coal is the result of geochemical cycles in the earth's crust. Additionally, stratum fracture zones may serve as conduits and material sources for the migration of HTEs from deep layers to shallow layers, including coal seams. This study provides an essential reference for extensive map applications and coal environmental management while advancing our understanding of the spatial distribution patterns of chemical elements in coal.


Assuntos
Água Subterrânea , Oligoelementos , China , Carvão Mineral/análise , Monitoramento Ambiental , Oligoelementos/análise
10.
Sci Total Environ ; 755(Pt 1): 142527, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33032133

RESUMO

Harmful trace elements in coal have caused serious damage to the environment and human health. Understanding their spatial distribution is helpful for environmental health assessment and for their effective control and utilization. To further explore the geospatial distribution of harmful trace elements found in Chinese coals, this work constructed the Trace Elements in Chinese Coals Database Management System (TECC), and analysed the spatial distribution of harmful trace elements by applying spatial data algorithms and visual technology of WebGIS. The main results are as follows: (1) The mean concentrations of 25 harmful trace elements (Ag, As, B, Ba, Be, Cd, Cl, Co, Cr, Cu, F, Hg, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Th, Tl, U, V, Zn) in Chinese coals are provided, using the "reserve-concentration" weighted calculation method; (2) Using As, Hg, F, and U as examples, the spatial distribution of harmful trace elements in Chinese coalfields is visually displayed; (3) Harmful trace elements are extremely unevenly distributed in Chinese coalfields; they are mainly concentrated in south China, especially in the southwest region, and some elements may also be concentrated in coals from northwest, northeast, and north China. The enrichment of harmful trace elements in Chinese coals is the result of a combination of multiple factors, such as the nature of the region the coal is sourced from, sedimentary facies, coal-forming plants, and magmatic hydrothermal processes. This work can serve as a reference for the study of harmful trace elements in coal, including assessment of their environmental and health impacts.

11.
FASEB J ; 23(7): 2299-306, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19244313

RESUMO

Serotonin (5-HT) stimulates pulmonary artery smooth muscle cell proliferation and has been associated with pulmonary arterial hypertension (PAH). Bone morphogenetic protein receptor 2 (BMPR2) mutations similarly have been linked to PAH. However, possible crosstalk between 5-HT and BMPR signaling remains poorly characterized. We report here that 5-HT activates Smads 1/5/8 in bovine and human pulmonary artery smooth muscle cells (SMCs) and causes translocation of these Smads from cytoplasm to the nucleus. DN BMPR1A blocked 5-HT activation of Smads 1/5/8 by 5-HT and BMPR1A overexpression enhanced it. Activation of Smads by 5-HT occurred through the 5-HT 1B/1D receptor as it was blocked with the inhibitor GR 55562 but unaffected by inhibitors of the 5-HT transporter and a variety of 5-HT receptors. Activation of the Smads by 5-HT depended on Rho/Rho kinase signaling as it was blocked by Y27632, but unaffected by inhibitors of PI3K or MAPK. Transfection of cells with BMPR1A and ligation of the BMP receptor with BMP-2 also activated GTP-Rho A of these SMCs, while DN BMPR1A blocked the activation. 5-HT stimulated an increase in serine/threonine phosphorylation of BMPR1A, supporting the activation of BMPR1A by 5-HT in SMCs. Infusion of 5-HT into mice with miniosmotic infusion pumps caused activation of Smads 1/5/8 in lung tissue, demonstrating the effect in vivo. The studies support a unique concept that 5-HT transactivates the serine kinase receptor, BMPR 1A, to activate Smads 1/5/8 via Rho and Rho kinase in pulmonary artery SMCs. Rho and Rho kinase also participate in the activation of Smads by BMP.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Miócitos de Músculo Liso/citologia , Artéria Pulmonar/citologia , Serotonina/farmacologia , Proteínas Smad Reguladas por Receptor/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Bovinos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Proteína Smad8/metabolismo , Ativação Transcricional
12.
Mol Cancer Res ; 18(1): 27-32, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31636091

RESUMO

Fibronectin-binding integrins α5ß1 and αv collaborate in prostate cancer-bone stromal interactions relevant to the colonization of the bone marrow microenvironment. Combinatorial inactivation of these integrins on prostate cancer cells was assessed. Monospecific antibodies to α5ß1and αv integrins alone (MAb) and in combination (cMAb), and a bispecific antibody that simultaneously targets α5ß1and αv integrins (BsAbα5ß1/αv) were compared in assays of chemotaxis, clonogenic survival, and induction of endothelial migration. Cellular expression of integrins, their transcription, translation, and degradation fate was compared. The BsAbα5ß1/αv was superior to MAbs and cMAbs in abrogating adhesion, migration, clonogenic survival, and induction of endothelial migration responses by prostate cancer cells. Integrin upregulation observed with MAbs or cMAbs was abrogated with the BsAbα5ß1/αv. Loss of integrin expression was uniquely induced by the BsAbα5ß1/αv and blocked by lysosomal inhibition. IMPLICATIONS: A novel and effective combinatorial strategy to target α5ß1and αv integrins is defined for translational studies. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/18/1/27/F1.large.jpg.


Assuntos
Anticorpos Biespecíficos/uso terapêutico , Integrina alfa5beta1/metabolismo , Integrinas/metabolismo , Neoplasias da Próstata/genética , Anticorpos Biespecíficos/farmacologia , Movimento Celular , Humanos , Masculino
13.
Transl Androl Urol ; 9(4): 1630-1638, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32944524

RESUMO

BACKGROUND: Collaborative signaling between fibronectin-binding αv and α5 integrins has been implicated in the lethal dissemination of prostate cancer in the bone-metastatic niche, the major source of morbidity and mortality in the disease. METHODS: We assessed the frequency and pattern of expression of these integrins in primary high-grade adenocarcinomas and bone metastases compared to the physiological gland. Formalin-fixed paraffin-embedded (FFPE) radical prostatectomy (RP) samples (n=25) containing ≥ Gleason grade 4 cancer and decalcified surgical or diagnostic bone metastatic samples from 10 patients were stained for integrin αv (ITGAV) and integrin α5 (ITGA5) expression. Antibody optimization and antigen-retrieval was performed beforehand. RESULTS: ITGAV was exclusively expressed in the basal layer of physiological prostate glands whereas αv expression was invariably recapitulated in the malignant gland and bone metastases (100%) in multiple distinct patterns: epithelial membranous, basilar/luminal membranous, punctate cytoplasmic, intense foci as single cells or clusters, and rim stromal layers. The luminal/basilar layer of ITGAV expression was striking in cribriform carcinomas, suggestive of a role in molecular pathogenesis. ITGA5 infrequently highlighted the basal layer of the physiological gland, was absent in primary adenocarcinoma, but was expressed with ITGAV exclusively in bone metastases (71%). CONCLUSIONS: We conclude that ITGAV expression is aberrantly expressed in high frequency in high-grade prostatic adenocarcinomas in patterns suggestive of recapitulated basal cell functions, consistent with a stem-regulatory role that has been proposed. Co-expression and enrichment of αv and α5 in osseous metastases supports their proposed collaborative role in colonization of the bone microenvironment and as candidate targets for therapy.

14.
Cell Adh Migr ; 11(4): 305-315, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-27715399

RESUMO

The haematopoietic niche is contributed to by bone marrow-resident mesenchymal stromal cells (BM-MSCs) and subverted by prostate cancer cells. To study mechanisms by which BM-MSCs and prostate cancer cells may interact, we assessed the migration, invasion, adhesion and proliferation of bone-derived prostate cancer cells (PC-3) in co-culture with pluripotent human BM-MSCs. We observed a strong adhesive, migratory and invasive phenotype of PC-3 cells with BM- MSC-co-culture and set out to isolate and characterize the bioactive principle. Initial studies indicated that chemotaxis was secondary to a protein residing in the >100kDa fraction. Size-exclusion chromatography (SEC) recovered peak activity in a high-molecular weight fraction containing thrombospondin-1 (TSP1). While TSP1 immunodepletion decreased activity, put-back with purified TSP1 did not reproduce bioactivity. Further purification of the TSP1-containing high-molecular weight fraction of the BM-MSC secretome with heparin-affinity chromatography recovered bioactivity with highly restricted bands on polyacrylamide gel electrophoresis, determined by mass spectroscopy to be proteolytic fragments of fibronectin (FN). Put-back experiments with full-length FN permitted adhesion but failed to induce migration. Monospecific antibodies to FN blocked adhesion. Proteolytic cleavage of FN generated FN fragments which now induced migration. Neutralizing monoclonal antibodies to FN receptors α5 and ß1 integrins, and α5 knockdown specifically blocked migration and adhesion. CONCLUSION: Fibronectin fragments (FNFr) function as matrikines driving the chemotactic affinity of prostate cancer cells via the α5ß1 integrin. Taken together with the high-frequency of α5ß1 expression in disseminated prostate cancer cells in bone marrow aspirates from patients, the FNFr/FN-α5ß1 interaction warrants further study as a therapeutic target.


Assuntos
Quimiotaxia , Fibronectinas/metabolismo , Integrina alfa5beta1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteólise , Osso e Ossos/patologia , Adesão Celular , Linhagem Celular Tumoral , Cromatografia de Afinidade , Técnicas de Cocultura , Heparina , Humanos , Masculino , Invasividade Neoplásica , Proteoma/metabolismo , Proteômica , Trombospondina 1/metabolismo
15.
Mol Cancer Res ; 14(12): 1176-1181, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27590631

RESUMO

The bone-conserved metastatic phenotype of prostate cancer is a prototype of nonrandom metastatic behavior. Adhesion of prostate cancer cells to fibronectin via the integrin α5 (ITGA5) has been proposed as a candidate bone marrow niche localization mechanism. We hypothesized that the mechanisms whereby ITGA5 regulates the adhesion-mediated survival of prostate cancer cells will define novel therapeutic approaches. ITGA5 shRNA reduced expression of BCL-2 family members and induced apoptosis in PC-3 cells. In these PTEN-mutant cells, pharmacologic inhibition of the PI3K signaling pathway in combination with ITGA5 knockdown enhanced apoptosis. Chemical parsing studies with BH3 mimetics indicated that PI3K/Akt inhibition in combination with BCL-XL-specific inhibition induces synergistic apoptosis specifically in PTEN-mutant prostate cancer cells, whereas single-agent PI3K/Akt inhibitors did not. Given the importance of PTEN loss in the progression of prostate and other cancers, synthetic lethality induced by combinatorial PI3K/Akt and BCL-XL inhibition represents a valuable therapeutic strategy. IMPLICATIONS: Activation of the PI3K pathway through PTEN loss represents a major molecular pathway in the progression of prostate and other cancers. This study defines a synthetic lethal therapeutic combination with significant translational potential. OVERVIEW: Synthetic lethality in PTEN-mutant prostate cancer cells with combined PI3K/Akt and BCL-XL inhibition. PTEN-mutant prostate cancer cells expressing ITGA5 bind to fibronectin in the putative bone marrow niche and transduce survival signals to BCL-XL Additional PTEN-regulated signals independent of the PI3K/Akt pathway likely feed into the BCL-XL-regulated survival program to explain synthetic lethality observed with the combination.Visual Overview: http://mcr.aacrjournals.org/content/early/2016/12/02/1541-7786.MCR-16-0202/F1.large.jpg. Mol Cancer Res; 14(12); 1176-81. ©2016 AACR.


Assuntos
Aminopiridinas/farmacologia , Compostos de Anilina/farmacologia , Integrina alfa5/genética , Morfolinas/farmacologia , PTEN Fosfo-Hidrolase/genética , Piperazinas/farmacologia , Neoplasias da Próstata/genética , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Masculino , Inibidores de Fosfoinositídeo-3 Quinase , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Mutações Sintéticas Letais , Proteína bcl-X/antagonistas & inibidores
16.
Adipocyte ; 2(1): 17-28, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23599907

RESUMO

Protein palmitoylation, by modulating the dynamic interaction between protein and cellular membrane, is involved in a wide range of biological processes, including protein trafficking, sorting, sub-membrane partitioning, protein-protein interaction and cell signaling. To explore the role of protein palmitoylation in adipocytes, we have performed proteomic analysis of palmitoylated proteins in adipose tissue and 3T3-L1 adipocytes and identified more than 800 putative palmitoylated proteins. These include various transporters, enzymes required for lipid and glucose metabolism, regulators of protein trafficking and signaling molecules. Of note, key proteins involved in membrane translocation of the glucose-transporter Glut4 including IRAP, Munc18c, AS160 and Glut4, and signaling proteins in the JAK-STAT pathway including JAK1 and 2, STAT1, 3 and 5A and SHP2 in JAK-STAT, were palmitoylated in cultured adipocytes and primary adipose tissue. Further characterization showed that palmitoylation of Glut4 and IRAP was altered in obesity, and palmitoylation of JAK1 played a regulatory role in JAK1 intracellular localization. Overall, our studies provide evidence to suggest a novel and potentially regulatory role for protein palmitoylation in adipocyte function.

17.
Mol Cell Biol ; 33(21): 4255-65, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24001771

RESUMO

ClipR-59 interacts with Akt and regulates Akt compartmentalization and Glut4 membrane trafficking in a plasma membrane association-dependent manner. The association of ClipR-59 with plasma membrane is mediated by ClipR-59 palmitoylation at Cys534 and Cys535. To understand the regulation of ClipR-59 palmitoylation, we have examined all known mammalian DHHC palmitoyltransferases with respect to their ability to promote ClipR-59 palmitoylation. We found that, among 23 mammalian DHHC palmitoyltransferases, DHHC17 is the major ClipR-59 palmitoyltransferase, as evidenced by the fact that DHHC17 interacted with ClipR-59 and palmitoylated ClipR-59 at Cys534 and Cys535. By palmitoylating ClipR-59, DHHC17 directly regulates ClipR-59 plasma membrane association, as ectopic expression of DHHC17 increased whereas silencing of DHHC17 reduced the levels of ClipR-59 associated with plasma membrane. We have also examined the role of DHHC17 in Akt signaling and found that silencing of DHHC17 in 3T3-L1 adipocytes decreased the levels of Akt as well as ClipR-59 on the plasma membrane and impaired insulin-dependent Glut4 membrane translocation. We suggest that DHHC17 is a ClipR-59 palmitoyltransferase that modulates ClipR-59 plasma membrane binding, thereby regulating Akt signaling and Glut4 membrane translocation in adipocytes.


Assuntos
Aciltransferases/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Membrana Celular/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Processamento de Proteína Pós-Traducional , Animais , Células COS , Chlorocebus aethiops , Transportador de Glucose Tipo 4/metabolismo , Células HEK293 , Humanos , Insulina/fisiologia , Lipoilação , Proteínas Associadas aos Microtúbulos/química , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
18.
J Dermatol Sci ; 69(2): 114-21, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23182477

RESUMO

BACKGROUND: In some psoriatic patients, impaired function of FOXP3+ regulatory T cells has been identified without well-uncovered mechanism(s). Meanwhile, dysregulation of FOXP3 nuclear translocation has been observed in some autoimmune syndromes and in some cancer cells. OBJECTIVE: To investigate whether there is dysregulation of FOXP3 nuclear translocation in some psoriatic patients and to explore the signal pathway responsible for FOXP3 nuclear translocation. METHODS: CD4+CD25+ T cells were purified from peripheral blood mononuclear cells by magnetic-bead-based method. FOXP3 expression pattern in psoriasis was analyzed by immunohistochemical staining. Transient and stable cell lines were established by exogenous construct transfection and retrovirus infection respectively. Cytoplasmic and nuclear FOXP3 was analyzed by immunoprecipitation, western blot and immunofluorescence. RESULTS: We observed that some psoriatic patients showed cytoplasmic retention of FOXP3 and these patients had higher serum IL-17 and disease severity. We found that c-Jun N-terminal kinase (JNK) was essential to FOXP3 nuclear translocation. Inhibition of JNK pathway caused cytoplasmic retention of FOXP3. This inhibition could also impair the promotion of FOXP3 nuclear translocation by UVB. Next we found that phospho-c-JUN (ser63/73), main downstream of JNK pathway, could interact with FOXP3 and promoted FOXP3 nuclear translocation. CONCLUSION: Our study demonstrated that JNK-phospho-c-JUN (ser63/73) pathway was essential for FOXP3 nuclear translocation in psoriasis. Our study suggested selective manipulation of JNK in Tregs seems to be a promising choice for the development of drugs in the treatment of autoimmune inflammatory diseases.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Psoríase/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/fisiologia , Transporte Ativo do Núcleo Celular/efeitos da radiação , Adolescente , Adulto , Idoso , Antracenos/farmacologia , Núcleo Celular/metabolismo , Criança , Citoplasma/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Interleucina-17/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Fosforilação/fisiologia , Psoríase/imunologia , Psoríase/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Raios Ultravioleta , Adulto Jovem
19.
Med Res Rev ; 23(4): 519-34, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12710022

RESUMO

Flavonoids are polyphenolic compounds that are ubiquitously in plants. They have been shown to possess a variety of biological activities at nontoxic concentrations in organisms. The role of dietary flavonoids in cancer prevention is widely discussed. Compelling data from laboratory studies, epidemiological investigations, and human clinical trials indicate that flavonoids have important effects on cancer chemoprevention and chemotherapy. Many mechanisms of action have been identified, including carcinogen inactivation, antiproliferation, cell cycle arrest, induction of apoptosis and differentiation, inhibition of angiogenesis, antioxidation and reversal of multidrug resistance or a combination of these mechanisms. Based on these results, flavonoids may be promising anticancer agents.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Antioxidantes/química , Apoptose , Ciclo Celular , Diferenciação Celular , Divisão Celular , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos , Humanos , Modelos Químicos , Neovascularização Patológica , Extratos Vegetais
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 12(4): 406-10, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15363120

RESUMO

This study was purposed to characterize the first case of acute promyelocitic leukemia (AML-M(3a)) with t(15;17), trisomy 8 and tetrasomy 8, and explore its characteristics of morphology, cytogenetics, molecular biology, immunology and clinical features. Morphological changes of peripheral blood and bone marrow smears were observed under microscope. Chromosome specimen was prepared by 24 h short-term culture of bone marrow cell, RHG-banding technique was used for karyotypic analysis. PML-RARa fusion gene transcript was detected by nested-reverse transcription-polymerase chain reaction (nested RT-PCR). Interphase fluorescence in situ hybridization (FISH) using chromosome 8 centromere specific probe were carried out to detect abnormal numbers of chromosome 8. Immunophenotypic analysis was performed by flow cytometry. The results showed that peripheral blood smear revealed 65% promyelocyte, and bone marrow aspirate was hypercellular with 72.4% promyelocyte, moderately basophilic cytoplasm with numerous azurophilic granules. Karyotype analysis demonstrated 48, XY, +8, +8, t(15;17)(q22;q12) [16]/47, XY, +8, t(15;17)(q22;q12) [3]/46, XY, t(15;17)(q22;q12) [1]. RT-PCR assay revealed PML-RARa fusion gene transcript (+). FISH showed that the percentages of cells exhibiting 1, 2, 3, 4, 5, 6 green fluorescence signals were 0.5, 7, 19, 55, 18 and 0.5, respectively. This confirmed the presence of tetrasomy 8 and trisomy 8 and also revealed a low percentage of a pentasomy 8 clone. Immunophenotypes of the blasts displayed that CD13 (96.2%), CD33 (55.9%), CYMPO (93.5%) were positive. All the lymphoid markers tested were negative. The patient survival time was just 10 days. It is concluded that tetrasomy 8 is secondary cytogenetic event after t(15;17) in this case. It may be a consequence of clonal evolution of trisomy 8. t(15;17) AML-M(3) with tetrasomy 8 heralds a poor prognosis.


Assuntos
Cromossomos Humanos Par 15 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 8 , Leucemia Promielocítica Aguda/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética , Trissomia , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
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