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1.
Sci Rep ; 12(1): 2928, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190588

RESUMO

Biomarkers for treatment sensitivity or drug resistance used in precision medicine include prognostic and predictive molecules, critical factors in selecting appropriate treatment protocols and improving survival rates. However, identification of accurate biomarkers remain challenging due to the high risk of false-positive findings and lack of functional validation results for each biomarker. Here, we discovered a mechanical correlation between leucine proline-enriched proteoglycan 1 (LEPRE1) and pelitinib drug sensitivity using in silico statistical methods and confirmed the correlation in acute myeloid leukemia (AML) and A549 lung cancer cells. We determined that high LEPRE1 levels induce protein kinase B activation, overexpression of ATP-binding cassette superfamily G member 2 (ABCG2) and E-cadherin, and cell colonization, resulting in a cancer stem cell-like phenotype. Sensitivity to pelitinib increases in LEPRE1-overexpressing cells due to the reversing effect of ABCG2 upregulation. LEPRE1 silencing induces pelitinib resistance and promotes epithelial-to-mesenchymal transition through actin rearrangement via a series of Src/ERK/cofilin cascades. The in silico results identified a mechanistic relationship between LEPRE1 and pelitinib drug sensitivity, confirmed in two cancer types. This study demonstrates the potential of LEPRE1 as a biomarker in cancer through in-silico prediction and in vitro experiments supporting the clinical development of personalized medicine strategies based on bioinformatics findings.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Aminoquinolinas/farmacologia , Compostos de Anilina/farmacologia , Antineoplásicos/farmacologia , Biomarcadores Tumorais , Transição Epitelial-Mesenquimal/genética , Regulação Leucêmica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Prolil Hidroxilases/genética , Prolil Hidroxilases/fisiologia , Proteoglicanas/genética , Proteoglicanas/fisiologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Leucemia Mieloide Aguda/diagnóstico , Neoplasias Pulmonares/diagnóstico
3.
Curr Opin Nephrol Hypertens ; 28(4): 328-335, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30985337

RESUMO

PURPOSE OF REVIEW: To summarize the role of hypoxia signaling in skeletal cells. RECENT FINDINGS: Hypoxia occurs at several stages during bone development. Skeletal cells, like chondrocytes and osteoblasts, respond to this challenge by stabilizing the hypoxia inducible transcription factor HIF, which induces the expression of angiogenic factors and promotes glycolysis. The increased delivery of oxygen and nutrients, together with metabolic adaptations, prevent chondrocyte cell death in the growth plate and promote bone formation by osteoblasts. However, excessive HIF levels have to be avoided during bone development as the resulting metabolic maladaptations cause skeletal dysplasia. Recent studies show that HIF also targets other genes to increase bone mass: it decreases osteoclastogenesis by increasing osteoprotegerin expression and represses sclerostin expression by epigenetic mechanisms, resulting in increased bone formation and decreased resorption. Moreover, increased HIF signaling in osteolineage cells promotes primary and metastatic breast tumor growth, and induces erythropoietin (EPO) production, resulting in polycythemia. Finally, HIF can directly or indirectly through increasing EPO levels, induce the expression and processing of FGF23 and may thereby affect mineral homeostasis and vitamin D metabolism. SUMMARY: HIF signaling in skeletal cells not only affects their behavior but also influences erythropoiesis and possibly mineral homeostasis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Desenvolvimento Ósseo/fisiologia , Homeostase , Hipóxia/fisiopatologia , Oxigênio/metabolismo , Prolil Hidroxilases/fisiologia , Animais , Fator de Crescimento de Fibroblastos 23 , Humanos , Osteoblastos/fisiologia , Transdução de Sinais/fisiologia
4.
Br J Cancer ; 119(12): 1518-1526, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30410060

RESUMO

BACKGROUND: Extracellular matrix (ECM) plays a crucial role in tumour behaviour. Prolyl-4-hydroxlase-A2 (P4HA2) is a key enzyme in ECM remodelling. This study aims to evaluate the prognostic significance of P4HA2 in breast ductal carcinoma in situ (DCIS). METHODS: P4HA2 expression was assessed immunohistochemically in malignant cells and surrounding stroma of a large DCIS cohort comprising 481 pure DCIS and 196 mixed DCIS and invasive carcinomas. Outcome analysis was evaluated using local recurrence free interval (LRFI). RESULTS: High P4HA2 expression was detected in malignant cells of half of pure DCIS whereas its expression in stroma was seen in 25% of cases. Higher P4HA2 expression was observed in mixed DCIS cases compared to pure DCIS both in tumour cells and in stroma. High P4HA2 was associated with features of high risk DCIS including younger age, higher grade, comedo necrosis, triple negative and HER2-positive phenotypes. Interaction between P4HA2 and radiotherapy was also observed regarding the outcome. High P4HA2 expression was an independent prognostic factor in predicting shorter LRFI. CONCLUSION: P4HA2 plays a role in DCIS progression and can potentially be used to predict DCIS outcome. Incorporation of P4HA2 with other clinicopathological parameters could refine DCIS risk stratification that can potentially guide management decisions.


Assuntos
Neoplasias da Mama/enzimologia , Carcinoma Intraductal não Infiltrante/enzimologia , Prolil Hidroxilases/fisiologia , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Prolil Hidroxilases/análise
5.
J Pathol ; 242(3): 322-333, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28418093

RESUMO

Osteogenic-angiogenic coupling is promoted by the hypoxia-inducible factor 1-alpha (HIF-1α) transcription factor, provoking interest in HIF activation as a therapeutic strategy to improve osteoblast mineralization and treat pathological osteolysis. However, HIF also enhances the bone-resorbing activity of mature osteoclasts. It is therefore essential to determine the full effect(s) of HIF on both the formation and the bone-resorbing function of osteoclasts in order to understand how they might respond to such a strategy. Expression of HIF-1α mRNA and protein increased during osteoclast differentiation from CD14+ monocytic precursors, additionally inducing expression of the HIF-regulated glycolytic enzymes. However, HIF-1α siRNA only moderately affected osteoclast differentiation, accelerating fusion of precursor cells. HIF induction by inhibition of the regulatory prolyl-4-hydroxylase (PHD) enzymes reduced osteoclastogenesis, but was confirmed to enhance bone resorption by mature osteoclasts. Phd2+/- murine osteoclasts also exhibited enhanced bone resorption, associated with increased expression of resorption-associated Acp5, in comparison with wild-type cells from littermate controls. Phd3-/- bone marrow precursors displayed accelerated early fusion, mirroring results with HIF-1α siRNA. In vivo, Phd2+/- and Phd3-/- mice exhibited reduced trabecular bone mass, associated with reduced mineralization by Phd2+/- osteoblasts. These data indicate that HIF predominantly functions as a regulator of osteoclast-mediated bone resorption, with little effect on osteoclast differentiation. Inhibition of HIF might therefore represent an alternative strategy to treat diseases characterized by pathological levels of osteolysis. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Reabsorção Óssea/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Prolil Hidroxilases/fisiologia , Animais , Osso Esponjoso/fisiologia , Adesão Celular/fisiologia , Diferenciação Celular/fisiologia , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/deficiência , Leucócitos Mononucleares/patologia , Camundongos , RNA Mensageiro/metabolismo
6.
Biochim Biophys Acta ; 1866(2): 208-220, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27663420

RESUMO

Protein hydroxylation is a post-translational modification catalyzed by 2-oxoglutarate-dependent dioxygenases. The hydroxylation modification can take place on various amino acids, including but not limited to proline, lysine, asparagine, aspartate and histidine. A classical example of this modification is hypoxia inducible factor alpha (HIF-α) prolyl hydroxylation, which affects HIF-α protein stability via the Von-Hippel Lindau (VHL) tumor suppressor pathway, a Cullin 2-based E3 ligase adaptor protein frequently mutated in kidney cancer. In addition to protein stability regulation, protein hydroxylation may influence other post-translational modifications or the kinase activity of the modified protein (such as Akt and DYRK1A/B). In other cases, protein hydroxylation may alter protein-protein interaction and its downstream signaling events in vivo (such as OTUB1, MAPK6 and eEF2K). In this review, we highlight the recently identified protein hydroxylation targets and their pathophysiological roles, especially in cancer settings. Better understanding of protein hydroxylation will help identify novel therapeutic targets and their regulation mechanisms to foster development of more effective treatment strategies for various human cancers.


Assuntos
Prolil Hidroxilases/fisiologia , Proteínas/metabolismo , Animais , Humanos , Hidroxilação
7.
Cancer Res ; 76(19): 5845-5856, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27488520

RESUMO

Hypoxia is a common feature of solid tumors, which controls multiple aspects of cancer progression. One important function of hypoxia and the hypoxia-inducible factors (HIF) is the maintenance of cancer stem-like cells (CSC), a population of tumor cells that possess stem cell-like properties and drives tumor growth. Among the changes promoted by hypoxia is a metabolic shift resulting in acidification of the tumor microenvironment. Here, we show that glioma hypoxia and acidosis functionally cooperate in inducing HIF transcription factors and CSC maintenance. We found that these effects did not involve the classical PHD/VHL pathway for HIF upregulation, but instead involved the stress-induced chaperone protein HSP90. Genetic or pharmacologic inactivation of HSP90 inhibited the increase in HIF levels and abolished the self-renewal and tumorigenic properties of CSCs induced by acidosis. In clinical specimens of glioma, HSP90 was upregulated in the hypoxic niche and was correlated with a CSC phenotype. Our findings highlight the role of tumor acidification within the hypoxic niche in the regulation of HIF and CSC function through HSP90, with implications for therapeutic strategies to target CSC in gliomas and other hypoxic tumors. Cancer Res; 76(19); 5845-56. ©2016 AACR.


Assuntos
Acidose/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Neoplasias Encefálicas/patologia , Glioma/patologia , Proteínas de Choque Térmico HSP90/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Células-Tronco Neoplásicas/fisiologia , Prolil Hidroxilases/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/fisiologia , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Feminino , Glioma/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos
8.
Biochim Biophys Acta ; 1863(8): 2027-36, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27155083

RESUMO

Pharmacological inhibition of oxygen sensing prolyl hydroxylase domain enzymes (PHDs) has been shown to preserve renal structure and function in various models of kidney disease. Since transforming growth factor ß-1 (TGFß-1) is one of the major mediators of kidney injury, we investigated if inhibition of PHDs with subsequent stabilization of hypoxia inducible transcription factors (HIF) might interfere with TGFß-1 signaling with special emphasis on its target gene connective tissue growth factor (CTGF). Overnight incubation of human renal tubular cells, primary cells and cell lines, with the PDH inhibitor DMOG increased Smad3 expression, but barely affected Smad2. Both Smads were translocated into the nucleus upon activation of the cells with TGFß-1. Interestingly, Smad3 nuclear localization was enhanced upon pretreatment of the cells with DMOG for several hours, whereas nuclear Smad2 was reduced. This differential localization was independent of Smad2/3 phosphorylation. Reduced nuclear Smad2 correlated with impaired CTGF secretion in DMOG-treated cells and transient downregulation of Smad2 interfered with TGFß-1-induced CTGF synthesis. Furthermore, YAP was confirmed as indispensable transcription factor involved in CTGF synthesis. Nuclear localization of YAP and TAZ was reduced in DMOG-treated cells. Our data thus provide evidence for DMOG-mediated reduction of CTGF expression by regulating the nuclear localization of the transcription factors Smad2, YAP and TAZ. Prolonged inhibition of PHDs was necessary to achieve alterations in cellular localization suggesting an indirect HIF-mediated effect. This mechanism might be extended to other transcription factors and target genes, and may thus represent a novel mechanism of negative regulation of gene expression by PHD inhibition.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fator de Crescimento do Tecido Conjuntivo/biossíntese , Túbulos Renais/metabolismo , Fosfoproteínas/metabolismo , Prolil Hidroxilases/fisiologia , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular , Aciltransferases , Proteínas Adaptadoras de Transdução de Sinal/genética , Aminoácidos Dicarboxílicos/farmacologia , Hipóxia Celular/genética , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Fator de Crescimento do Tecido Conjuntivo/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Túbulos Renais/citologia , Oxigênio/metabolismo , Fosfoproteínas/genética , Cultura Primária de Células , Interferência de RNA , RNA Interferente Pequeno/genética , Proteína Smad2/genética , Fator de Crescimento Transformador beta1/fisiologia , Proteínas de Sinalização YAP
9.
Leukemia ; 29(6): 1366-78, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25578474

RESUMO

Many patients with hematological neoplasms fail to mobilize sufficient numbers of hematopoietic stem cells (HSCs) in response to granulocyte colony-stimulating factor (G-CSF) precluding subsequent autologous HSC transplantation. Plerixafor, a specific antagonist of the chemokine receptor CXCR4, can rescue some but not all patients who failed to mobilize with G-CSF alone. These refractory poor mobilizers cannot currently benefit from autologous transplantation. To discover alternative targetable pathways to enhance HSC mobilization, we studied the role of hypoxia-inducible factor-1α (HIF-1α) and the effect of HIF-1α pharmacological stabilization on HSC mobilization in mice. We demonstrate in mice with HSC-specific conditional deletion of the Hif1a gene that the oxygen-labile transcription factor HIF-1α is essential for HSC mobilization in response to G-CSF and Plerixafor. Conversely, pharmacological stabilization of HIF-1α with the 4-prolyl hydroxylase inhibitor FG-4497 synergizes with G-CSF and Plerixafor increasing mobilization of reconstituting HSCs 20-fold compared with G-CSF plus Plerixafor, currently the most potent mobilizing combination used in the clinic.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Prolil Hidroxilases/fisiologia , Animais , Fármacos Anti-HIV/farmacologia , Benzilaminas , Western Blotting , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclamos , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células-Tronco Hematopoéticas/metabolismo , Compostos Heterocíclicos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibidores de Prolil-Hidrolase/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/antagonistas & inibidores , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Autólogo
10.
J Neurosci ; 34(49): 16348-57, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25471573

RESUMO

Neuronal wiring during development requires that the growth cones of axons and dendrites are correctly guided to their appropriate targets. As in other animals, axon growth cones in Caenorhabditis elegans integrate information in their extracellular environment via interactions among transiently expressed cell surface receptors, their ligands, and the extracellular matrix (ECM). Components of the ECM undergo a wide variety of post-translational modifications that may affect efficacy of binding to neuronal guidance molecules. The most common modification of the ECM is prolyl 4-hydroxylation. However, little is known of its importance in the control of axon guidance. In a screen of prolyl 4-hydroxylase (P4H) mutants, we found that genetic removal of a specific P4H subunit, DPY-18, causes dramatic defects in C. elegans neuroanatomy. In dpy-18 mutant animals, the axons of specific ventral nerve cord neurons do not respect the ventral midline boundary and cross over to the contralateral axon fascicle. We found that these defects are independent of the known role of dpy-18 in regulating body size and that dpy-18 acts from multiple tissues to regulate axon guidance. Finally, we found that the neuronal defects in dpy-18 mutant animals are dependent on the expression of muscle-derived basement membrane collagens and motor neuron-derived ephrin ligands. Loss of dpy-18 causes dysregulated ephrin expression and this is at least partially responsible for the neurodevelopmental defects observed. Together, our data suggest that DPY-18 regulates ephrin expression to direct axon guidance, a role for P4Hs that may be conserved in higher organisms.


Assuntos
Axônios/fisiologia , Caenorhabditis elegans/citologia , Caenorhabditis elegans/metabolismo , Prolil Hidroxilases/fisiologia , Animais , Axônios/ultraestrutura , Rastreamento de Células , Efrinas/metabolismo , Hidroxilação , Neurônios Motores/fisiologia , Neurônios Motores/ultraestrutura , Mutação , Prolil Hidroxilases/genética , Subunidades Proteicas/genética , Subunidades Proteicas/fisiologia
11.
J Prosthodont Res ; 58(4): 193-207, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25311991

RESUMO

Periodontal ligament (PDL) plays critical roles in the development and maintenance of periodontium such as tooth eruption and dissipation of masticatory force. The mechanical properties of PDL are mainly derived from fibrillar type I collagen, the most abundant extracellular component. The biosynthesis of type I collagen is a long, complex process including a number of intra- and extracellular post-translational modifications. The final modification step is the formation of covalent intra- and intermolecular cross-links that provide collagen fibrils with stability and connectivity. It is now clear that collagen post-translational modifications are regulated by groups of specific enzymes and associated molecules in a tissue-specific manner; and these modifications appear to change in response to mechanical force. This review focuses on the effect of mechanical loading on collagen biosynthesis and fibrillogenesis in PDL with emphasis on the post-translational modifications of collagens, which is an important molecular aspect to understand in the field of prosthetic dentistry.


Assuntos
Colágeno Tipo I/biossíntese , Colágeno Tipo I/genética , Ligamento Periodontal/metabolismo , Animais , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Chaperonas Moleculares/fisiologia , Peptidilprolil Isomerase/fisiologia , Ligamento Periodontal/fisiologia , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/fisiologia , Prolil Hidroxilases/fisiologia , Prostodontia , Processamento de Proteína Pós-Traducional
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