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1.
Philos Trans R Soc Lond B Biol Sci ; 376(1816): 20190714, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33250025

RESUMO

In many theories on the social and cultural evolution of human societies, the number and density of people living together in a given time and region is a crucial factor. Because direct data on past demographic developments are lacking, and reliability and validity of demographic proxies require careful evaluation, the topic has been approached from several different directions. This paper provides an introduction to a geostatistical approach for estimating prehistoric population size and density, the so-called Cologne Protocol and discusses underlying theoretical assumptions and upscaling transfer-functions between different spatial scale levels. We describe and compare the specifics for farming and for foraging societies and, using examples, discuss a diachronic series of estimates, covering the population dynamics of roughly 40 kyr of European prehistory. Ethnohistoric accounts, results from other approaches-including absolute (ethno-environmental models) and relative estimates (site-numbers, dates as data, etc.) allow a first positioning of the estimates within this field of research. Future enhancements, applications and testing of the Cologne Protocol are outlined and positioned within the general theoretical and methodological avenues of palaeodemographic research. In addition, we provide manuals for modelling Core Areas in MapInfo, ArcGIS, QGIS/Saga and R. This article is part of the theme issue 'Cross-disciplinary approaches to prehistoric demography'.


Assuntos
Arqueologia , Demografia , Estilo de Vida , Europa (Continente) , Humanos , Dinâmica Populacional
2.
Br J Pharmacol ; 176(23): 4474-4490, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31351004

RESUMO

BACKGROUND AND PURPOSE: Aerobic glycolysis is a unique feature of tumour cells that entails several advantages for cancer progression such as resistance to apoptosis. The low MW compound, dichloroacetate, is a pyruvate dehydrogenase kinase inhibitor, which restores oxidative phosphorylation and induces apoptosis in a variety of cancer entities. However, its therapeutic effectiveness is limited by resistance mechanisms. This study aimed to examine the role of the anti-apoptotic hyaluronan (HA) matrix in this context and to identify a potential add-on treatment option to overcome this limitation. EXPERIMENTAL APPROACH: The metabolic connection between dichloroacetate treatment and HA matrix augmentation was analysed in vitro by quantitative PCR and affinity cytochemistry. Metabolic pathways were analysed using Seahorse, HPLC, fluorophore-assisted carbohydrate electrophoresis, colourimetry, immunoblots, and immunochemistry. The effects of combining dichloroacetate with the HA synthesis inhibitor 4-methylumbelliferone was evaluated in 2D and 3D cell cultures and in a nude mouse tumour xenograft regression model by immunoblot, immunochemistry, and FACS analysis. KEY RESULTS: Mitochondrial reactivation induced by dichloroacetate metabolically activated HA synthesis by augmenting precursors as well as O-GlcNAcylation. This process was blocked by 4-methylumbelliferone, resulting in enhanced anti-tumour efficacy in 2D and 3D cell culture and in a nude mouse tumour xenograft regression model. CONCLUSIONS AND IMPLICATIONS: The HA rich tumour micro-environment represents a metabolic factor contributing to chemotherapy resistance. HA synthesis inhibition exhibited pronounced synergistic actions with dichloroacetate treatment on oesophageal tumour cell proliferation and survival in vitro and in vivo suggesting the combination of these two strategies is an effective anticancer therapy.


Assuntos
Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Matriz Extracelular/efeitos dos fármacos , Ácido Hialurônico/antagonistas & inibidores , Animais , Antineoplásicos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácido Dicloroacético , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Matriz Extracelular/metabolismo , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/metabolismo , Himecromona , Masculino , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Análise de Regressão , Relação Estrutura-Atividade , Células Tumorais Cultivadas
3.
Matrix Biol ; 66: 67-80, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28987865

RESUMO

OBJECTIVE: Hyaluronan (HA) is a prominent component of the provisional extracellular matrix (ECM) present in the neointima of atherosclerotic plaques. Here the role of HA synthase 3 (HAS3) in atheroprogression was studied. APPROACH AND RESULTS: It is demonstrated here that HAS isoenzymes 1, -2 and -3 are expressed in human atherosclerotic plaques of the carotid artery. In Apolipoprotein E (Apoe)-deficient mice Has3 expression is increased early during lesion formation when macrophages enter atherosclerotic plaques. Importantly, HAS3 expression in vascular smooth muscle cells (VSMC) was found to be regulated by interleukin 1 ß (IL-1ß) in an NFkB dependent manner and blocking antibodies to IL-1ß abrogate Has3 expression in VSMC by activated macrophages. Has3/Apoe double deficient mice developed less atherosclerosis characterized by decreased Th1-cell responses, decreased IL-12 release, and decreased macrophage-driven inflammation. CONCLUSIONS: Inhibition of HAS3-dependent synthesis of HA dampens systemic Th1 cell polarization and reduces plaque inflammation. These data suggest that HAS3 might be a promising therapeutic target in atherosclerosis. Moreover, because HAS3 is regulated by IL-1ß, our results suggest that therapeutic anti-IL-1ß antibodies, recently tested in human clinical trials (CANTOS), may exert their beneficial effects on inflammation in post-myocardial infarction patients in part via effects on HAS3. TOC categorybasic study TOC subcategoryarteriosclerosis.


Assuntos
Apolipoproteínas E/deficiência , Hialuronan Sintases/metabolismo , Interleucina-1beta/metabolismo , Músculo Liso Vascular/citologia , Placa Aterosclerótica/metabolismo , Animais , Polaridade Celular , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Humanos , Ácido Hialurônico/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , NF-kappa B/farmacocinética , Placa Aterosclerótica/genética , Placa Aterosclerótica/imunologia , Células Th1/citologia , Células Th1/metabolismo
4.
Arterioscler Thromb Vasc Biol ; 36(2): e9-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26586662

RESUMO

OBJECTIVE: Hyaluronan (HA) is a polymeric glucosaminoglycan that forms a provisional extracellular matrix in diseased vessels. HA is synthesized by 3 different HA synthases (HAS1, HAS2, and HAS3). Aim of this study was to unravel the role of the HAS3 isoenzyme during experimental neointimal hyperplasia. APPROACH AND RESULTS: Neointimal hyperplasia was induced in Has3-deficient mice by ligation of the carotid artery. HA in the media of Has3-deficient mice was decreased 28 days after ligation, and neointimal hyperplasia was strongly inhibited. However, medial and luminal areas were unaffected. Cell density, proliferation, and apoptosis were not altered, suggesting a proportional decrease of both, the number of cells and extracellular matrix. In addition, endothelial function as determined by acetylcholine-induced relaxation of aortic rings, immunoblotting of endothelial nitric oxide synthase, and arterial blood pressure were not affected. Furthermore, the oxidative stress response was not affected as determined in total protein extracts from aortae. Transcriptome analysis comparing control versus ligated carotid arteries hinted toward a mitigated differential regulation of various signaling pathways in Has3-deficient mice in response to ligation that were related to vascular smooth muscle cell (VSMC) migration, including focal adhesions, integrins, mitogen-activated protein kinase, and phosphatidylinositol signaling system. Lentiviral overexpression of HAS3 in VSMC supported the migratory phenotype of VSMC in response to platelet-derived growth factor BB in vitro. Accordingly, knockdown of HAS3 reduced the migratory response to platelet-derived growth factor BB and in addition decreased the expression of PDGF-B mRNA. CONCLUSIONS: HAS3-mediated HA synthesis after vessel injury supports seminal signaling pathways in activation of VSMC, increases platelet-derived growth factor BB-mediated migration, and in turn enhances neointimal hyperplasia in vivo.


Assuntos
Doenças das Artérias Carótidas/enzimologia , Glucuronosiltransferase/deficiência , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , Neointima , Animais , Becaplermina , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/patologia , Artéria Carótida Primitiva/enzimologia , Artéria Carótida Primitiva/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Matriz Extracelular/metabolismo , Feminino , Deleção de Genes , Regulação da Expressão Gênica , Genótipo , Glucuronosiltransferase/genética , Hialuronan Sintases , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Fenótipo , Proteínas Proto-Oncogênicas c-sis/genética , Proteínas Proto-Oncogênicas c-sis/metabolismo , Proteínas Proto-Oncogênicas c-sis/farmacologia , Transdução de Sinais , Transcrição Gênica , Transfecção
5.
J Biol Chem ; 291(8): 4091-106, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26699196

RESUMO

The aim of this study was to characterize the interaction of KYSE-410, an esophageal squamous cell carcinoma cell line, and fibroblasts with respect to the extracellular matrix component hyaluronan (HA) and chemokine expression. KYSE-410 cells induced the mRNA expression of HA synthase 2 (Has2) in normal skin fibroblasts (SF) only in direct co-cultures. Parallel to Has2 mRNA, Has2 antisense RNA (Has2os2) was up-regulated in co-cultures. Knockdown of LEF1, a downstream target of Wnt signaling, abrogated Has2 and Has2os2 induction. After knockdown of Has2 in SF, significantly less α-smooth muscle actin expression was detected in co-cultures. Moreover, it was investigated whether the phenotype of KYSE-410 was affected in co-culture with SF and whether Has2 knockdown in SF had an impact on KYSE-410 cells in co-culture. However, no effects on epithelial-mesenchymal transition markers, proliferation, and migration were detected. In addition to Has2 mRNA, the chemokine CCL5 was up-regulated and CCL11 was down-regulated in SF in co-culture. Furthermore, co-cultures of KYSE-410 cells and cancer-associated fibroblasts (CAF) were investigated. Similar to SF, Has2 and Ccl5 were up-regulated and Ccl11 was down-regulated in CAF in co-culture. Importantly and in contrast to SF, inhibiting HA synthesis by 4-methylumbelliferone abrogated the effect of co-culture on Ccl5 in CAF. Moreover, HA was found to promote adhesion of CD4(+) but not CD8(+) cells to xenogaft tumor tissues. In conclusion, direct co-culture of esophageal squamous cell carcinoma and fibroblasts induced stromal HA synthesis via Wnt/LEF1 and altered the chemokine profile of stromal fibroblasts, which in turn may affect the tumor immune response.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Quimiocina CCL11/biossíntese , Quimiocina CCL5/biossíntese , Neoplasias Esofágicas/metabolismo , Fibroblastos/metabolismo , Ácido Hialurônico/biossíntese , Proteínas de Neoplasias/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Quimiocina CCL11/genética , Quimiocina CCL5/genética , Técnicas de Cocultura , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Fibroblastos/patologia , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Humanos , Hialuronan Sintases , Ácido Hialurônico/genética , Fator 1 de Ligação ao Facilitador Linfoide/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Via de Sinalização Wnt
6.
Basic Res Cardiol ; 109(6): 440, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25236954

RESUMO

Interleukin-6 (IL-6) is a multifunctional cytokine that orchestrates the immune response to a wide variety of pathophysiologic challenges but also contributes to tissue homeostasis. Furthermore, IL-6 is elevated in patients with acute myocardial infarction. Hyaluronan (HA) is an extracellular carbohydrate that has been implicated in wound healing and accumulates after acute myocardial infarction (AMI). Aim of this study was to investigate the involvement of IL-6 in the regulation of the HA-matrix in the early phase of infarct healing. In the present study, we show by the use of a blocking anti-IL-6 antibody, that endogenous IL-6 rapidly but transiently increased HA-synthase (HAS) 1 and 2 expression resulting in the formation of a HA-rich matrix acutely after AMI in mice. In vitro, IL-6 induced HAS1 and 2 via STAT3 phosphorylation in cardiac fibroblasts (CF) and supported a myofibroblastic phenotype in a HA-dependent manner. Furthermore, CCL5 and MCP1 expression were dependent on IL-6, HA-synthesis and the HA-receptor CD44 as shown in cultured CF derived from CD44 knockout mice. In vivo after AMI, blocking IL-6 decreased HA-matrix formation in the peri-infarct region and alpha-smooth muscle actin-positive myofibroblasts. Blocking IL-6 also reduced neutrophil infiltration in infarcted left ventricles. Moreover, treatment with the blocking IL-6 antibody reduced cardiac ejection fraction and increased infarct size 3 weeks after AMI. These findings support a functionally important role for IL-6 in CF by transiently inducing a HA-rich matrix that in turn promotes a myofibroblastic phenotype and inflammatory responses, and ultimately establishes a cardioprotective program after AMI.


Assuntos
Fibroblastos/fisiologia , Ácido Hialurônico/fisiologia , Interleucina-6/fisiologia , Infarto do Miocárdio , Animais , Matriz Extracelular/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/genética , Miofibroblastos/fisiologia , Fenótipo
7.
PLoS One ; 8(11): e80084, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223213

RESUMO

BACKGROUND: Urothelial bladder cancer is the ninth most common cancer. Despite surgical and chemotherapeutic treatment the prognosis is still poor once bladder cancer progresses to a muscle-invasive state. Discovery of new diagnostic markers and pathophysiologic effectors might help to contribute to novel diagnostic and therapeutic options. The extracellular matrix microenvironment shaped by the extracellular matrix critically affects tumor cell and stroma cell functions. Therefore, aim of the present study was to assess the possible implication of the small leucine-rich proteoglycan biglycan in progression of human urothelial bladder cancer. METHODS AND RESULTS: For this purpose tumor biopsies of 76 bladder cancer patients with different tumor stages (pTa, pT1-T4) were investigated with respect to biglycan expression and correlated with a long-term (10 years) clinical follow-up. Interestingly, higher biglycan mRNA expression was associated with higher tumor stages and muscle invasiveness. In vitro knock-down of endogenous biglycan in human urothelial carcinoma cells (J82 cells) increased proliferation, whereas addition of recombinant biglycan and overexpression of biglycan inhibited tumor cell proliferation. In line with this growth-inhibitory effect of biglycan, transplantation of J82 cells after knock-down of biglycan resulted in significantly increased growth of subcutaneous xenograft tumors in nude mice in vivo. Furthermore, treatment with two anti-proliferative, multi-receptor tyrosine kinase inhibitors-sunitinib and sorafenib-strongly upregulated biglycan expression. Collectively, the experimental data suggest that high biglycan expression is associated with reduced tumor cell proliferation. In accordance, Kaplan-Meier analysis revealed higher 10-year survival in patients with high biglycan mRNA expression in tumor biopsies. CONCLUSION: In conclusion, the present data suggest that biglycan is an endogenous inhibitor of bladder cancer cell proliferation that is upregulated in response to anti-proliferative tyrosine kinase inhibitors. In addition, high biglycan expression is associated with favorable prognosis.


Assuntos
Biglicano/química , Biglicano/metabolismo , Leucina/química , Neoplasias da Bexiga Urinária/metabolismo , Animais , Biglicano/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Indóis/uso terapêutico , Masculino , Camundongos , Camundongos Nus , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Pirróis/uso terapêutico , RNA Mensageiro/genética , Sorafenibe , Sunitinibe , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética
8.
PLoS One ; 8(9): e75681, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24069434

RESUMO

UNLABELLED: Hyaluronan (HA) is a carbohydrate of the extracellular matrix with tumor promoting effects in a variety of cancers. The present study addressed the role of HA matrix for progression and prognosis of human bladder cancer by studying the expression and function of HA-related genes. METHODS: Tissue samples of 120 patients with different stages of transitional cell bladder cancer, who underwent surgical treatment for bladder cancer at the University Hospital of Essen were analysed. mRNA-expression levels of HA synthases (HAS1-3) and HA-receptors (RHAMM and CD44) were evaluated by real time RT-PCR in comparison to healthy bladder tissue as control. In uni- and multivariate cox proportional hazard survival regression analysis, the impact of the gene expression levels on survival was assessed. In vitro knock-down of RHAMM, CD44 and HAS isoenzymes was achieved by siRNA and lentiviral shRNA in J82 bladder cancer cells. Transfected cells were analysed in vitro with regard to proliferation, cell cycle and apoptosis. J82 cells after knock-down of RHAMM were xenografted into male nu/nu athymic mice to monitor tumor progression in vivo. RESULTS: In invasive tumor stages RHAMM-, HAS1 and HAS2 mRNA-expression levels were elevated whereas HAS3v1 was reduced as compared to non-invasive tumors. Subsequently, Kaplan-Meier analysis revealed reduced bladder cancer specific survival in patients with high RHAMM mRNA and low HAS3v1 expression. Elevated RHAMM in invasive tumors was confirmed by RHAMM immunohistochemistry. Furthermore, multivariate analysis revealed that only RHAMM expression was associated with poor prognosis independent from other survival factors (HR=2.389, 95% CI 1.227-4.651, p=0.01). Lentiviral RHAMM knock-down revealed reduced J82 cell proliferation in vitro and reduced xenograft tumor growth in vivo. CONCLUSION: The data suggest that RHAMM plays a crucial role in mediating progression of muscle-invasive bladder cancer and recommends RHAMM for further evaluation as a prognostic marker or therapeutic target in bladder cancer therapy.


Assuntos
Carcinoma de Células de Transição/genética , Proteínas da Matriz Extracelular/genética , Receptores de Hialuronatos/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Modelos Animais de Doenças , Progressão da Doença , Proteínas da Matriz Extracelular/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Imuno-Histoquímica , Imunofenotipagem , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Fenótipo , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Risco , Carga Tumoral/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
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