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1.
Nutrients ; 13(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684595

RESUMO

BACKGROUND: Noncommunicable diseases (NCDs) are the leading global cause of death and share common risk factors. Little quantitative data are available on the patterns of each NCDs death and dietary factors by national income level and region. We aimed to identify the trend of NCDs deaths and dietary factors with other health-related behaviors across national income levels and geographical regions. METHODS: Three databases were collected, including the World Health Organization, Food and Agriculture Organization, and World Bank in 2014. These were analyzed to describe the trend for NCDs deaths and dietary factors with health-related behaviors across national income levels (high income, upper-middle income, lower-middle income, and low income) from 151 countries using variance-weighted least-squares linear regression. RESULTS: Lower-middle-income and low-income countries in Africa and Asia had higher death rates of NCDs. More than 30% of the population had raised blood pressure with higher carbohydrate intake and lower protein and fat intake compared to high-income European countries in 2014. High-income countries had the highest prevalence of raised total cholesterol, overweight, and obesity, the highest total energy, fat, and protein intake, and the highest supplies of animal fat, stimulants, sugar and sweetener, vegetable oil, and milk, as well as insufficient activity with an increasing trend (p for trend < 0.001). CONCLUSION: There were differences in NCDs risk factors and dietary factors by national income and region. Accordingly, measures should be taken to suit the situation in each country. Our findings have significance for health workers and health policies preventing and controlling the rise of NCDs.


Assuntos
Dieta , Renda , Doenças não Transmissíveis/economia , Doenças não Transmissíveis/epidemiologia , Ingestão de Energia , Humanos , Internacionalidade , Doenças não Transmissíveis/mortalidade , Estado Nutricional , Fatores de Risco
2.
Adv Mater ; 30(18): e1706237, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29543353

RESUMO

Waterborne polyurethanes (WBPUs) have attracted increasing attention in a wide range of industrial applications because of their versatile properties as well as ecofriendly nature. Although extensive research has been carried out on WBPU synthesis, the roles of some of the key synthesis components remain unclear. In this study, through systematically controlling and fine tuning the precursor compositions and reaction conditions, over 300 WBPUs are synthesized. This research enables the roles of several key components that govern WBPU physicochemical properties and ultimately the potential WBPU applications to be identified. Using hair styling as an example, it is demonstrated that only the WBPUs with an optimal range of properties (e.g., Young's modulus >150 MPa, elongation at break: 15-300%, moisture uptake <10%) can achieve strong styling performance. To further improve the natural-feel sensory benefits in the final styling products, a number of fatty acids with different carbon chain lengths or unsaturation levels are incorporated into WBPUs. Among the ten fatty acids studied, linoleic acid is identified as the most preferred additive. Both in vitro and in vivo testing demonstrate that WBPUs with optimal properties are promising materials for developing strong, long-lasting styling products with natural feel.

3.
Nat Mater ; 15(8): 911-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27159017

RESUMO

We report the synthesis and application of an elastic, wearable crosslinked polymer layer (XPL) that mimics the properties of normal, youthful skin. XPL is made of a tunable polysiloxane-based material that can be engineered with specific elasticity, contractility, adhesion, tensile strength and occlusivity. XPL can be topically applied, rapidly curing at the skin interface without the need for heat- or light-mediated activation. In a pilot human study, we examined the performance of a prototype XPL that has a tensile modulus matching normal skin responses at low strain (<40%), and that withstands elongations exceeding 250%, elastically recoiling with minimal strain-energy loss on repeated deformation. The application of XPL to the herniated lower eyelid fat pads of 12 subjects resulted in an average 2-grade decrease in herniation appearance in a 5-point severity scale. The XPL platform may offer advanced solutions to compromised skin barrier function, pharmaceutical delivery and wound dressings.


Assuntos
Materiais Biomiméticos , Elasticidade , Teste de Materiais , Pele , Adulto , Materiais Biomiméticos/química , Engenharia , Feminino , Humanos , Siloxanas/química , Resistência à Tração
4.
Mol Biol Cell ; 27(4): 669-85, 2016 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-26700321

RESUMO

Syntaxin-1 is the central SNARE protein for neuronal exocytosis. It interacts with Munc18-1 through its cytoplasmic domains, including the N-terminal peptide (N-peptide). Here we examine the role of the N-peptide binding in two conformational states ("closed" vs. "open") of syntaxin-1 using PC12 cells and Caenorhabditis elegans. We show that expression of "closed" syntaxin-1A carrying N-terminal single point mutations (D3R, L8A) that perturb interaction with the hydrophobic pocket of Munc18-1 rescues impaired secretion in syntaxin-1-depleted PC12 cells and the lethality and lethargy of unc-64 (C. elegans orthologue of syntaxin-1)-null mutants. Conversely, expression of the "open" syntaxin-1A harboring the same mutations fails to rescue the impairments. Biochemically, the L8A mutation alone slightly weakens the binding between "closed" syntaxin-1A and Munc18-1, whereas the same mutation in the "open" syntaxin-1A disrupts it. Our results reveal a striking interplay between the syntaxin-1 N-peptide and the conformational state of the protein. We propose that the N-peptide plays a critical role in intracellular trafficking of syntaxin-1, which is dependent on the conformational state of this protein. Surprisingly, however, the N-peptide binding mode seems dispensable for SNARE-mediated exocytosis per se, as long as the protein is trafficked to the plasma membrane.


Assuntos
Proteínas de Caenorhabditis elegans/química , Exocitose , Proteínas Munc18/metabolismo , Neurônios/fisiologia , Sintaxina 1/química , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Técnicas de Silenciamento de Genes , Dados de Sequência Molecular , Neurônios/metabolismo , Células PC12 , Peptídeos/química , Peptídeos/metabolismo , Mutação Puntual , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Ratos , Sintaxina 1/genética , Sintaxina 1/metabolismo
5.
Mol Cancer Res ; 12(5): 754-64, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24574516

RESUMO

UNLABELLED: The angiogenic switch, a rate-limiting step in tumor progression, has already occurred by the time most human tumors are detectable. However, despite significant study of the mechanisms controlling this switch, the kinetics and reversibility of the process have not been explored. The stability of the angiogenic phenotype was examined using an established human liposarcoma xenograft model. Nonangiogenic cells inoculated into immunocompromised mice formed microscopic tumors that remained dormant for approximately 125 days (vs. <40 days for angiogenic cells) whereupon the vast majority (>95%) initiated angiogenic growth with second-order kinetics. These original, clonally derived angiogenic tumor cells were passaged through four in vivo cycles. At each cycle, a new set of single-cell clones was established from the most angiogenic clone and characterized for in vivo for tumorigenic activity. A total of 132 single-cell clones were tested in the second, third, and fourth in vivo passage. Strikingly, at each passage, a portion of the single-cell clones formed microscopic, dormant tumors. Following dormancy, like the original cell line, these revertant tumors spontaneously switched to the angiogenic phenotype. Finally, revertant clones were transcriptionally profiled and their angiogenic output determined. Collectively, these data demonstrate that the angiogenic phenotype in tumors is malleable and can spontaneously revert to the nonangiogenic phenotype in a population of human tumor cells. IMPLICATIONS: Leveraging the rate of reversion to the nonangiogenic phenotype and tumor dormancy may be a novel anticancer strategy.


Assuntos
Lipossarcoma/irrigação sanguínea , Lipossarcoma/patologia , Animais , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Expressão Gênica , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos SCID , Neovascularização Patológica/patologia , Fenótipo
6.
J Cell Sci ; 126(Pt 11): 2361-71, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23525015

RESUMO

Munc18-1 is believed to prime or stimulate SNARE-mediated membrane fusion/exocytosis through binding to the SNARE complex, in addition to chaperoning its cognate syntaxins. Nevertheless, a Munc18-1 mutant that selectively loses the priming function while retaining the syntaxin chaperoning activity has not been identified. As a consequence, the mechanism that mediates Munc18-1-dependent priming remains unclear. In the course of analyzing the functional outcomes of a variety of point mutations in domain 3a of Munc18-1, we discovered insertion mutants (K332E/K333E with insertions of 5 or 39 residues). These mutants completely lose their ability to rescue secretion whereas they effectively restore syntaxin-1 expression at the plasma membrane as well as dense-core vesicle docking in Munc18-1 and Munc18-2 double-knockdown PC12 cells. The mutants can bind syntaxin-1A in a stoichiometric manner. However, binding to the SNARE complex is impaired compared with the wild type or the hydrophobic pocket mutant (F115E). Our results suggest that the domain 3a of Munc18-1 plays a crucial role in priming of exocytosis, which is independent of its syntaxin-1 chaperoning activity and is downstream of dense-core vesicle docking. We also suggest that the priming mechanism of Munc18-1 involves its domain-3a-dependent interaction with the SNARE complex.


Assuntos
Exocitose/fisiologia , Fusão de Membrana/fisiologia , Proteínas Munc18/metabolismo , Proteínas SNARE/metabolismo , Animais , Proteínas Munc18/genética , Células PC12 , Mutação Puntual , Estrutura Terciária de Proteína , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Ratos , Proteínas SNARE/genética
7.
Proc Natl Acad Sci U S A ; 109(22): 8699-704, 2012 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-22589302

RESUMO

The mechanisms underlying tumor dormancy have been elusive and not well characterized. We recently published an experimental model for the study of human tumor dormancy and the role of angiogenesis, and reported that the angiogenic switch was preceded by a local increase in VEGF-A and basic fibroblast growth factor. In this breast cancer xenograft model (MDA-MB-436 cells), analysis of differentially expressed genes revealed that heat shock protein 27 (HSP27) was significantly up-regulated in angiogenic cells compared with nonangiogenic cells. The effect of HSP27 down-regulation was further evaluated in cell lines, mouse models, and clinical datasets of human patients with breast cancer and melanoma. Stable down-regulation of HSP27 in angiogenic tumor cells was followed by long-term tumor dormancy in vivo. Strikingly, only 4 of 30 HSP27 knockdown xenograft tumors initiated rapid growth after day 70, in correlation with a regain of HSP27 protein expression. Significantly, no tumors escaped from dormancy without HSP27 expression. Down-regulation of HSP27 was associated with reduced endothelial cell proliferation and decreased secretion of VEGF-A, VEGF-C, and basic fibroblast growth factor. Conversely, overexpression of HSP27 in nonangiogenic cells resulted in expansive tumor growth in vivo. By clinical validation, strong HSP27 protein expression was associated with markers of aggressive tumors and decreased survival in patients with breast cancer and melanoma. An HSP27-associated gene expression signature was related to molecular subgroups and survival in breast cancer. Our findings suggest a role for HSP27 in the balance between tumor dormancy and tumor progression, mediated by tumor-vascular interactions. Targeting HSP27 might offer a useful strategy in cancer treatment.


Assuntos
Neoplasias da Mama/metabolismo , Regulação para Baixo , Proteínas de Choque Térmico HSP27/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Animais , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP27/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos SCID , Neovascularização Patológica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo
8.
Mol Biol Cell ; 22(18): 3394-409, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21795392

RESUMO

The Vo sector of the vacuolar H(+)-ATPase is a multisubunit complex that forms a proteolipid pore. Among the four isoforms (a1-a4) of subunit Voa, the isoform(s) critical for secretory vesicle acidification have yet to be identified. An independent function of Voa1 in exocytosis has been suggested. Here we investigate the function of Voa isoforms in secretory vesicle acidification and exocytosis by using neurosecretory PC12 cells. Fluorescence-tagged and endogenous Voa1 are primarily localized on secretory vesicles, whereas fluorescence-tagged Voa2 and Voa3 are enriched on the Golgi and early endosomes, respectively. To elucidate the functional roles of Voa1 and Voa2, we engineered PC12 cells in which Voa1, Voa2, or both are stably down-regulated. Our results reveal significant reductions in the acidification and transmitter uptake/storage of dense-core vesicles by knockdown of Voa1 and more dramatically of Voa1/Voa2 but not of Voa2. Overexpressing knockdown-resistant Voa1 suppresses the acidification defect caused by the Voa1/Voa2 knockdown. Unexpectedly, Ca(2+)-dependent peptide secretion is largely unaffected in Voa1 or Voa1/Voa2 knockdown cells. Our data demonstrate that Voa1 and Voa2 cooperatively regulate the acidification and transmitter uptake/storage of dense-core vesicles, whereas they might not be as critical for exocytosis as recently proposed.


Assuntos
Neurotransmissores/metabolismo , Norepinefrina/metabolismo , Subunidades Proteicas/metabolismo , Vesículas Secretórias/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Dopamina/metabolismo , Endossomos/metabolismo , Técnicas de Silenciamento de Genes , Concentração de Íons de Hidrogênio , Fusão de Membrana , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Células PC12 , Isoformas de Proteínas/metabolismo , Subunidades Proteicas/genética , Transporte Proteico , Ratos , Proteínas Recombinantes de Fusão/metabolismo , Vesículas Secretórias/química , Sinaptotagminas/metabolismo , Regulação para Cima , ATPases Vacuolares Próton-Translocadoras/genética
9.
Proc Natl Acad Sci U S A ; 106(29): 12115-20, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19581582

RESUMO

Metastatic tumors can prepare a distant site for colonization via the secretion of factors that act in a systemic manner. We hypothesized that non- or weakly metastatic human tumor cells may act in an opposite fashion by creating a microenvironment in distant tissues that is refractory to colonization. By comparing cell lines with different metastatic potential, we have identified a tumor-secreted inhibitor of metastasis, prosaposin (Psap), which functions in a paracrine and endocrine fashion by stimulating the expression of thrombospondin-1 (Tsp-1) in fibroblasts present in both primary tumors and distant organs, doing so in a p53-dependent manner. Introduction of Psap in highly metastatic cells significantly reduced the occurrence of metastases, whereas inhibition of Psap production by tumor cells was associated with increased metastatic frequency. In human prostate cancer, decreased Psap expression was significantly associated with metastatic tumors. Our findings suggest that prosaposin, or other agents that stimulate p53 activity in the tumor stroma, may be an effective therapy by inhibition of the metastatic process.


Assuntos
Células Endócrinas/metabolismo , Metástase Neoplásica/patologia , Comunicação Parácrina , Saposinas/metabolismo , Células Estromais/metabolismo , Trombospondina 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Células Estromais/patologia
10.
APMIS ; 116(7-8): 638-47, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18834408

RESUMO

Tumor dormancy is a critical yet poorly understood phenomenon affecting both the diagnosis and treatment of human cancers. This is due in large part to the lack of model systems available to study dormant tumor cells and the length of time needed to adequately examine the models that do exist. It has been demonstrated in several types of human cancer that tumor dormancy is a function of an impairment in angiogenesis. The intracellular signaling pathways regulating the expression of several pro- and anti-angiogenic proteins have been well characterized in human cancer cells. The intercellular signaling that takes place between tumor cells and the surrounding tumor-associated stroma has not been as extensively studied with regard to the regulation of angiogenesis, and as a result dormancy. In this review we define the key players in the regulation of angiogenesis and examine how their expression is regulated in the tumor-associated stroma. The resulting analysis is often seemingly paradoxical, underscoring the complexity of intercellular signaling within tumors and the need to better understand the environmental context underlying these signaling mechanisms.


Assuntos
Neoplasias/patologia , Neoplasias/fisiopatologia , Trombospondina 1/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Hormônios/fisiologia , Humanos , Neoplasias/irrigação sanguínea , Neovascularização Patológica , Comunicação Parácrina/fisiologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Fator de Crescimento Transformador beta/fisiologia
11.
Cancer Cell ; 14(3): 201-11, 2008 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-18772110

RESUMO

Solid tumors require new blood vessels for growth and metastasis, yet the biology of tumor-specific endothelial cells is poorly understood. We have isolated tumor endothelial cells from mice that spontaneously develop prostate tumors. Clonal populations of tumor endothelial cells expressed hematopoietic and mesenchymal stem cell markers and differentiated to form cartilage- and bone-like tissues. Chondrogenic differentiation was accompanied by an upregulation of cartilage-specific col2a1 and sox9, whereas osteocalcin and the metastasis marker osteopontin were upregulated during osteogenic differentiation. In human and mouse prostate tumors, ectopic vascular calcification was predominately luminal and colocalized with the endothelial marker CD31. Thus, prostate tumor endothelial cells are atypically multipotent and can undergo a mesenchymal-like transition.


Assuntos
Calcinose/patologia , Transdiferenciação Celular , Endotélio Vascular/patologia , Neoplasias da Próstata/patologia , Fosfatase Alcalina/metabolismo , Animais , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Calcinose/genética , Calcinose/metabolismo , Condrócitos/metabolismo , Condrócitos/patologia , Colágeno Tipo II/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais/transplante , Endotélio Vascular/metabolismo , Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteocalcina/metabolismo , Osteócitos/metabolismo , Osteócitos/patologia , Osteopontina/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Fatores de Transcrição SOX9 , Antígenos Thy-1/metabolismo , Análise Serial de Tecidos , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas
12.
Circ Res ; 103(2): 194-202, 2008 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-18556575

RESUMO

The success of therapeutic vascularization and tissue engineering will rely on our ability to create vascular networks using human cells that can be obtained readily, can be expanded safely ex vivo, and can produce robust vasculogenic activity in vivo. Here we describe the formation of functional microvascular beds in immunodeficient mice by coimplantation of human endothelial and mesenchymal progenitor cells isolated from blood and bone marrow. Evaluation of implants after 1 week revealed an extensive network of human blood vessels containing erythrocytes, indicating the rapid formation of functional anastomoses within the host vasculature. The implanted endothelial progenitor cells were restricted to the luminal aspect of the vessels; mesenchymal progenitor cells were adjacent to lumens, confirming their role as perivascular cells. Importantly, the engineered vascular networks remained patent at 4 weeks in vivo. This rapid formation of long-lasting microvascular networks by postnatal progenitor cells obtained from noninvasive sources constitutes an important step forward in the development of clinical strategies for tissue vascularization.


Assuntos
Células da Medula Óssea/citologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Sangue Fetal/citologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Neovascularização Fisiológica/fisiologia , Engenharia Tecidual/métodos , Células-Tronco Adultas/citologia , Células-Tronco Adultas/fisiologia , Animais , Células da Medula Óssea/fisiologia , Comunicação Celular/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Sangue Fetal/fisiologia , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Nus , Pericitos/citologia , Pericitos/fisiologia , Medicina Regenerativa , Transplante Heterólogo
13.
J Natl Cancer Inst ; 98(5): 316-25, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16507828

RESUMO

BACKGROUND: Microscopic human cancers can remain dormant for life. Tumor progression depends on sequential events, including a switch to the angiogenic phenotype, i.e., initial recruitment of new vessels. We previously demonstrated that human tumors contain tumor cell populations that are heterogeneous in angiogenic activity. Here, we separated angiogenic from nonangiogenic human tumor cell populations and compared their growth. METHODS: Severe combined immunodeficient (SCID) mice were inoculated with nonangiogenic human MDA-MB-436 breast adenocarcinoma, KHOS-24OS osteosarcoma, or T98G glioblastoma cells. Most of the resulting tumors remained microscopic (<1 mm diameter), but some eventually became angiogenic and enlarged and were used to isolate angiogenic tumor cells. Angiogenic and nonangiogenic tumor cells were inoculated into SCID mice, and time to the development of palpable tumors was determined. Cell proliferation was assayed in vitro by growth curves and in vivo by staining for proliferating cell nuclear antigen or Ki67. Microscopic tumors from both tumor cell populations were examined for histologic evidence of vascular development 14 days after inoculation in mice. Expression of the angiogenesis inhibitor thrombospondin-1 was examined by immunoblotting. RESULTS: Nonangiogenic tumors of each tumor type developed palpable tumors after means of 119 days (range: 53-185 days) for breast cancer, 238 days (184-291 days) for osteosarcoma, and 226 days (150-301 days) for glioblastoma. Angiogenic cells developed palpable tumors within 20 days after inoculation. However, nonangiogenic and angiogenic cells of each tumor type had similar proliferation rates. Fourteen days after tumor cell inoculation, tumors from angiogenic cells showed evidence of functional vasculature. In contrast, nonangiogenic tumors remained microscopic in size with absent or nonfunctional vasculature. Thrombospondin-1 expression was statistically significantly lower (by five- to 23-fold, depending on tumor type) in angiogenic than nonangiogenic cells. CONCLUSIONS: This model provides a conceptual framework and a reproducible in vivo system to study unresolved central questions in cancer biology regarding the initiation, reversibility, and molecular regulation of the timing of the angiogenic switch.


Assuntos
Adenocarcinoma/irrigação sanguínea , Glioblastoma/irrigação sanguínea , Neovascularização Patológica , Osteossarcoma/irrigação sanguínea , Animais , Linhagem Celular Tumoral , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos SCID , Fenótipo , Trombospondina 1/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Cancer Lett ; 194(1): 13-9, 2003 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-12706854

RESUMO

Anthocyanins, which are bioactive phytochemicals, are widely distributed in plants and especially enriched in tart cherries. Based on previous observations that tart cherry anthocyanins and their respective aglycone, cyanidin, can inhibit cyclooxygenase enzymes, we conducted experiments to test the potential of anthocyanins to inhibit intestinal tumor development in Apc(Min) mice and growth of human colon cancer cell lines. Mice consuming the cherry diet, anthocyanins, or cyanidin had significantly fewer and smaller cecal adenomas than mice consuming the control diet or sulindac. Colonic tumor numbers and volume were not significantly influenced by treatment. Anthocyanins and cyanidin also reduced cell growth of human colon cancer cell lines HT 29 and HCT 116. The IC(50) of anthocyanins and cyanidin was 780 and 63 microM for HT 29 cells, respectively and 285 and 85 microM for HCT 116 cells, respectively. These results suggest that tart cherry anthocyanins and cyanidin may reduce the risk of colon cancer.


Assuntos
Antocianinas/farmacologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Animais , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Frutas , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Modelos Químicos , Pigmentos Biológicos/farmacologia , Reação em Cadeia da Polimerase , Prunus , Células Tumorais Cultivadas
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