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1.
Int J Biol Macromol ; 262(Pt 2): 130084, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350584

RESUMO

Accidental bleeding is an unavoidable problem in daily life. To avoid the risk of excessive blood loss, it is urgent to design a functional material that can quickly stop bleeding. In this study, an efficient wound dressing for hemostasis was investigated. Based on the characteristics that Ca2+ and fish skin collagen (FSC) could activate the coagulation mechanism, hemostatic cotton was prepared by solvent replacement method using CaCl2, FSC, soluble starch (SS), and polyvinyl alcohol (PVA) as raw materials. The cytotoxicity test showed the Ca2+PVA/FSC-SS hemostatic cottons had good biocompatibility. The activated partial thromboplastin time (APTT) of Ca2+PVA/FSC-SS(4) was 35.34 s, which was 22.07 s faster than that of PVA/FSC-SS, indicating Ca2+PVA/FSC-SS mediated the endogenous coagulation system. In vitro coagulation test, Ca2+PVA/FSC-SS(4) could stop bleeding rapidly within 39.60 ± 5.16 s, and the ability of wound healing was higher than commercial product (Celox). This study developed a rapid procoagulant and hemostatic material, which had a promising application in a variety of environments.


Assuntos
Hemostáticos , Animais , Hemostáticos/farmacologia , Amido/farmacologia , Hemostasia , Coagulação Sanguínea , Colágeno , Álcool de Polivinil , Hemorragia , Etanol , Antibacterianos
2.
Sci Adv ; 9(37): eadi2562, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37703370

RESUMO

Norovirus is a leading cause of epidemic viral gastroenteritis, with no currently approved vaccines or antivirals. Murine norovirus (MNoV) is a well-characterized model of norovirus pathogenesis in vivo, and persistent strains exhibit lifelong intestinal infection. Interferon-λ (IFN-λ) is a potent antiviral that rapidly cures MNoV. We previously demonstrated that IFN-λ signaling in intestinal epithelial cells (IECs) controls persistent MNoV, and here demonstrate that IFN-λ acts on tuft cells, the exclusive site of MNoV persistence, to limit infection. While interrogating the source of IFN-λ to regulate MNoV, we confirmed that MDA5-MAVS signaling, required for IFN-λ induction to MNoV in vitro, controls persistent MNoV in vivo. We demonstrate that MAVS in IECs and not immune cells controls MNoV. MAVS in nonsusceptible enterocytes, but not in tuft cells, restricts MNoV, implicating noninfected cells as the IFN-λ source. Our findings indicate that host sensing of MNoV is distinct from cellular tropism, suggesting intercellular communication between IECs for antiviral signaling induction in uninfected bystander cells.


Assuntos
Infecções por Enterovirus , Norovirus , Animais , Camundongos , Enterócitos , Células Epiteliais , Transdução de Sinais , Antivirais/farmacologia , Interferon lambda
3.
Autophagy ; 18(5): 1062-1077, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34520306

RESUMO

Mutations in the macroautophagy/autophagy gene EPG5 are responsible for Vici syndrome, a human genetic disease characterized by combined immunodeficiency. Previously, we found that epg5-/- mice exhibit hyperinflammation in the lungs mediated by IL1B/IL-1ß and TNF/TNFα, resulting in resistance to influenza. Here, we find that disruption of Epg5 results in protection against multiple enteric viruses including norovirus and rotavirus. Gene expression analysis reveals IFNL/IFN-λ responsive genes as a key alteration. Further, mice lacking Epg5 exhibit substantial alterations of the intestinal microbiota. Surprisingly, germ-free mouse studies indicate Epg5-associated inflammation of both the intestine and lung is microbiota-independent. Genetic studies support IFNL signaling as the primary mediator of resistance to enteric viruses, but not of microbial dysbiosis, in epg5-/- mice. This study unveils an important role, unexpectedly independent of the microbiota, for autophagy gene Epg5 in host organism protection by modulating intestinal IFNL responses.Abbreviations: CTNNB1: catenin (cadherin associated protein), beta 1; DAPI: 4',6-diamidino-2-phenylindole; EPG5: ectopic P-granules autophagy protein 5 homolog (C. elegans); FT: fecal transplant; IFI44: interferon-induced protein 44; IFIT1: interferon-induced protein with tetratricopeptide repeats 1; IFNG/IFN-γ: interferon gamma; IFNL/IFN-λ: interferon lambda; IFNLR1: interferon lambda receptor 1; IL1B/IL-1ß: interleukin 1 beta; ISG: interferon stimulated gene; GF: germ-free; LEfSe: linear discriminant analysis effect size; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MNoV: murine norovirus; MX2: MX dynamin-like GTPase 2; OAS1A: 2'-5' oligoadenylate synthetase 1A; RV: rotavirus; SPF: specific-pathogen free; SQSTM1/p62: sequestosome 1; STAT1: signal transducer and activator of transcription 1; STING1: stimulator of interferon response cGAMP interactor 1; TBK1: TANK-binding kinase 1; TNF/TNFα: tumor necrosis factor.


Assuntos
Proteínas Relacionadas à Autofagia , Intestinos , Microbiota , Proteínas de Transporte Vesicular , Animais , Fatores de Restrição Antivirais , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Intestinos/imunologia , Intestinos/patologia , Camundongos , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Fator de Necrose Tumoral alfa , Proteínas de Transporte Vesicular/genética
4.
J Clin Invest ; 122(10): 3579-92, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22996695

RESUMO

The adenosine diphosphate (ADP) receptor P2RY12 (purinergic receptor P2Y, G protein coupled, 12) plays a critical role in platelet aggregation, and P2RY12 inhibitors are used clinically to prevent cardiac and cerebral thrombotic events. Extracellular ADP has also been shown to increase osteoclast (OC) activity, but the role of P2RY12 in OC biology is unknown. Here, we examined the role of mouse P2RY12 in OC function. Mice lacking P2ry12 had decreased OC activity and were partially protected from age-associated bone loss. P2ry12-/- OCs exhibited intact differentiation markers, but diminished resorptive function. Extracellular ADP enhanced OC adhesion and resorptive activity of WT, but not P2ry12-/-, OCs. In platelets, ADP stimulation of P2RY12 resulted in GTPase Ras-related protein (RAP1) activation and subsequent αIIbß3 integrin activation. Likewise, we found that ADP stimulation induced RAP1 activation in WT and integrin ß3 gene knockout (Itgb3-/-) OCs, but its effects were substantially blunted in P2ry12-/- OCs. In vivo, P2ry12-/- mice were partially protected from pathologic bone loss associated with serum transfer arthritis, tumor growth in bone, and ovariectomy-induced osteoporosis: all conditions associated with increased extracellular ADP. Finally, mice treated with the clinical inhibitor of P2RY12, clopidogrel, were protected from pathologic osteolysis. These results demonstrate that P2RY12 is the primary ADP receptor in OCs and suggest that P2RY12 inhibition is a potential therapeutic target for pathologic bone loss.


Assuntos
Difosfato de Adenosina/fisiologia , Remodelação Óssea/fisiologia , Osteoclastos/fisiologia , Osteoporose/fisiopatologia , Receptores Purinérgicos P2Y12/fisiologia , Animais , Artrite Experimental/complicações , Neoplasias Ósseas/complicações , Neoplasias Ósseas/secundário , Remodelação Óssea/efeitos dos fármacos , Reabsorção Óssea/fisiopatologia , Carcinoma/complicações , Carcinoma/secundário , Adesão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Clopidogrel , Ativação Enzimática/efeitos dos fármacos , Feminino , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoporose/etiologia , Osteoporose/prevenção & controle , Ovariectomia , Fosfatidilinositol 3-Quinases/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Receptores Purinérgicos P2Y12/deficiência , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Receptores Purinérgicos P2Y12/genética , Organismos Livres de Patógenos Específicos , Ticlopidina/análogos & derivados , Ticlopidina/farmacologia , Ticlopidina/uso terapêutico , Proteínas rap1 de Ligação ao GTP/efeitos dos fármacos
5.
Cancer Res ; 72(4): 897-907, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22186138

RESUMO

Hedgehog (Hh) signaling is implicated in bone development and cellular transformation. Here we show that inhibition of Hh pathway activity inhibits tumor growth through effects on the microenvironment. Pharmacologic inhibition of the Hh effector Smoothened (Smo) increased trabecular bone in vivo and inhibited osteoclastogenesis in vitro. In addition, enhanced Hh signaling due to heterozygosity of the Hh inhibitory receptor Patched (Ptch1(+/-)) increased bone resorption, suggesting direct regulation of osteoclast (OC) activity by the Hh pathway. Ptch1(+/-) mice had increased bone metastatic and subcutaneous tumor growth, suggesting that increased Hh activation in host cells promoted tumor growth. Subcutaneous growth of Hh-resistant tumor cells was inhibited by LDE225, a novel orally bioavailable SMO antagonist, consistent with effects on tumor microenvironment. Knockdown of the Hh ligand Sonic Hh (SHH) in these cells decreased subcutaneous tumor growth and decreased stromal cell production of interleukin-6, indicating that tumor-derived Hh ligands stimulated tumor growth in a paracrine fashion. Together our findings show that inhibition of the Hh pathway can reduce tumor burden, regardless of tumor Hh responsiveness, through effects on tumor cells, OCs, and stromal cells within the tumor microenvironment. Hh may be a promising therapeutic target for solid cancers and bone metastases.


Assuntos
Neoplasias Ósseas/prevenção & controle , Osso e Ossos/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Neoplasias Experimentais/metabolismo , Microambiente Tumoral , Alcaloides de Veratrum/farmacologia , Animais , Neoplasias Ósseas/secundário , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Proteínas Hedgehog/antagonistas & inibidores , Heterozigoto , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/patologia , Osteoclastos/efeitos dos fármacos , Receptores Patched , Receptor Patched-1 , Receptores de Superfície Celular/genética , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Transdução de Sinais , Receptor Smoothened
6.
Vasc Endovascular Surg ; 45(8): 720-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22262116

RESUMO

BACKGROUND: To investigate whether estrogen may attenuate neointima formation in hyperhomocysteinemic rat carotid endarterectomy. METHODS: Rats were divided into 6 groups: ovariectomized estradiol-treated homocysteine or chow; ovariectomized placebo-treated homocysteine or chow; intact placebo-treated homocysteine or chow. Chow served as controls while homocysteine served as exaggerated intimal hyperplasia. Prior to endarterectomy, rats were implanted with estradiol mini-pump or placebo, diets given 2 weeks before and after surgery. Homocysteine, estrogen, and neointimal hyperplasia were determined. RESULTS: Homocysteine was elevated in homocysteine groups versus controls except in estradiol-treated group. Intimal hyperplasia increased in placebo-treated ovariectomized homocysteine versus intact group. Exaggerated intimal hyperplasia in placebo-treated ovariectomized homocysteine was reduced by estrogen and so was homocysteine. Estrogen replacement in ovariectomized homocysteine group reduced intimal hyperplasia to that of intact or ovariectomized controls. CONCLUSION: Estradiol treatment in this ovariectomized hyperhomocysteinemia carotid endarterectomy and resultant attenuation of homocysteine and neointima may have relevance to the beneficial effects of estrogen on hyperplastic response.


Assuntos
Lesões das Artérias Carótidas/tratamento farmacológico , Artéria Carótida Primitiva/efeitos dos fármacos , Estenose das Carótidas/prevenção & controle , Endarterectomia das Carótidas/efeitos adversos , Estradiol/administração & dosagem , Túnica Íntima/efeitos dos fármacos , Angioplastia/efeitos adversos , Animais , Biomarcadores/sangue , Lesões das Artérias Carótidas/sangue , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/patologia , Artéria Carótida Primitiva/patologia , Artéria Carótida Primitiva/cirurgia , Estenose das Carótidas/sangue , Estenose das Carótidas/etiologia , Estenose das Carótidas/patologia , Modelos Animais de Doenças , Estradiol/sangue , Terapia de Reposição de Estrogênios , Feminino , Homocisteína/sangue , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/complicações , Hiperplasia , Bombas de Infusão Implantáveis , Veias Jugulares/transplante , Ovariectomia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Túnica Íntima/patologia , Túnica Íntima/cirurgia
7.
PLoS One ; 5(12): e15755, 2010 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-21209895

RESUMO

The ARF tumor suppressor regulates p53 as well as basic developmental processes independent of p53, including osteoclast activation, by controlling ribosomal biogenesis. Here we provide evidence that ARF is a master regulator of bone remodeling and osteosarcoma (OS) development in mice. Arf(-/-) mice displayed increased osteoblast (OB) and osteoclast (OC) activity with a significant net increase in trabecular bone volume. The long bones of Arf(-/-) mice had increased expression of OB genes while Arf(-/-) OB showed enhanced differentiation in vitro. Mice transgenic for the Tax oncogene develop lymphocytic tumors with associated osteolytic lesions, while Tax+Arf(-/-) mice uniformly developed spontaneous OS by 7 months of age. Tax+Arf(-/-) tumors were well differentiated OS characterized by an abundance of new bone with OC recruitment, expressed OB markers and displayed intact levels of p53 mRNA and reduced Rb transcript levels. Cell lines established from OS recapitulated characteristics of the primary tumor, including the expression of mature OB markers and ability to form mineralized tumors when transplanted. Loss of heterozygosity in OS tumors arising in Tax+Arf(+/-) mice emphasized the necessity of ARF-loss in OS development. Hypothesizing that inhibition of ARF-regulated bone remodeling would repress development of OS, we demonstrated that treatment of Tax+Arf(-/-) mice with zoledronic acid, a bisphosphonate inhibitor of OC activity and repressor of bone turnover, prevented or delayed the onset of OS. These data describe a novel role for ARF as a regulator of bone remodeling through effects on both OB and OC. Finally, these data underscore the potential of targeting bone remodeling as adjuvant therapy or in patients with genetic predispositions to prevent the development of OS.


Assuntos
Carcinoma/genética , Produtos do Gene tax/genética , Osteoblastos/citologia , Osteoclastos/citologia , Proteína Supressora de Tumor p14ARF/genética , Animais , Remodelação Óssea , Difosfonatos/química , Difosfonatos/farmacologia , Genes p53 , Heterozigoto , Imidazóis/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Genéticos , Proteína Supressora de Tumor p53/metabolismo , Ácido Zoledrônico
8.
FASEB J ; 24(4): 1117-27, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19933310

RESUMO

The purpose of this work was to determine platelet and myeloid cell-specific requirements for beta3-containing integrins in hemostasis, bone resorption, and tumor growth. LoxP-flanked mice were generated to study the conditional deletion of beta3-integrin in platelets [knockout in platelets (KOP)] and myeloid cells [knockout in myeloid (KOM)]. Using the beta3KOP and beta3KOM strains of mice, we studied the role of beta3-integrin in hemostasis, bone resorption, and subcutaneous tumor growth. Tissue-specific deletion of platelet beta3-integrins in beta3KOP mice did not affect bone mass but resulted in a severe bleeding phenotype. No growth difference of tumor xenografts or in neoangiogenesis were found in beta3KOP mice, in contrast to the defects observed in germline beta3(-/-) mice. Conditional deletion of myeloid beta3-integrins in beta3KOM mice resulted in osteopetrosis but had no effect on hemostasis or mortality. Tumor growth in beta3KOM mice was increased and accompanied by decreased macrophage infiltration, without increase in blood vessel number. Platelet beta3-integrin deficiency was sufficient to disrupt hemostasis but had no effect on bone mass or tumor growth. Myeloid-specific beta3-integrin deletion was sufficient to perturb bone mass and enhance tumor growth due to reduced macrophage infiltration in the tumors. These results suggest that beta3-integrins have cell-specific roles in complex biological processes.-Morgan, E. A., Schneider, J. G., Baroni, T. E., Uluçkan, O., Heller, E., Hurchla, M. A., Deng, H., Floyd, D., Berdy, A., Prior, J. L., Piwnica-Worms, D., Teitelbaum, S. L., Ross, F. P., Weilbaecher, K. N. Dissection of platelet and myeloid cell defects by conditional targeting of the beta3-integrin subunit.


Assuntos
Plaquetas/metabolismo , Reabsorção Óssea/metabolismo , Hemostasia , Integrina beta3/metabolismo , Macrófagos/metabolismo , Melanoma/metabolismo , Animais , Plaquetas/patologia , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Linhagem Celular Tumoral , Hemorragia/genética , Hemorragia/metabolismo , Hemorragia/patologia , Humanos , Integrina beta3/genética , Macrófagos/patologia , Melanoma/genética , Melanoma/patologia , Camundongos , Camundongos Knockout , Transplante de Neoplasias , Especificidade de Órgãos/genética , Transplante Heterólogo
9.
J Nucl Med ; 50(11): 1873-80, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19875645

RESUMO

UNLABELLED: This article describes the evaluation of the radiopharmaceutical (64)Cu-CB-TE2A-c(RGDyK) ((64)Cu-RGD) as an imaging agent for osteolytic bone metastases and their associated inflammation by targeting of the alpha(v)beta(3) integrin on osteoclasts and the proinflammatory cells involved at the bone metastatic site. METHODS: The (64)Cu-RGD radiotracer was evaluated in the transgenic mouse expressing Tax (Tax(+)), which spontaneously develops osteolytic tumors throughout the vertebrae and hind limbs, using biodistribution studies and small-animal PET/CT. Histologic analysis was also performed on Tax(+) mouse tails, using hematoxylin and eosin and tartrate-resistant acid phosphatase to confirm the presence of osteolytic bone lesions and the presence of osteoclasts, respectively. Additionally, a proof-of-principle study was conducted with a small group of Tax(+) animals presenting with osteolytic lesions. These animals were treated with the bisphosphonate zoledronic acid and imaged with (64)Cu-RGD to determine whether this radiopharmaceutical was sensitive enough to detect a response to the bisphosphonate therapy. RESULTS: Biodistribution studies using (64)Cu-RGD demonstrated that Tax(+) mice between the ages of 6 and 12 mo had a greater accumulation of activity in their tail vertebrae than did the wild-type (WT) cohort (P = 0.013). Additionally, Tax(+) mice between the ages of 6 and 12 mo had significantly more tracer activity associated with their tail vertebrae than did Tax(+) mice older than 12 mo (P = 0.003), suggesting that earlier bone metastases cause an increased recruitment of alpha(v)beta(3)-expressing cells. Small-animal PET/CT with (64)Cu-RGD was conducted on Tax(+) and WT mice. On the basis of standardized uptake value analysis, Tax(+) mice had approximately 2-fold more tail-associated activity than did WT animals (P = 0.0157). Additionally, decreases in uptake were observed in the tails of Tax(+) mice after treatment with the osteoclast inhibitor zoledronic acid, and histologic analysis of Tax(+) mouse-tail vertebrae revealed the presence of Tax(+) tumor cells, osteoclasts, and proinflammatory cells within the bone microenvironment. CONCLUSION: Together, these data suggest that (64)Cu-RGD has the potential to effectively image osteolytic bone metastases and monitor the physiologic changes in the bone metastatic microenvironment after osteoclast-inhibiting bisphosphonate therapy.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/secundário , Osteólise/complicações , Osteólise/diagnóstico , Receptores de Vitronectina/metabolismo , Animais , Neoplasias Ósseas/complicações , Neoplasias Ósseas/metabolismo , Radioisótopos de Cobre/química , Diagnóstico Diferencial , Difosfonatos/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Produtos do Gene tax/metabolismo , Humanos , Leucemia de Células T/diagnóstico , Camundongos , Mieloma Múltiplo/diagnóstico , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Osteoclastos/patologia , Osteólise/metabolismo , Osteólise/patologia , Tomografia por Emissão de Pósitrons , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/metabolismo , Cauda , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
Bone ; 44(5): 908-16, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19442620

RESUMO

Bisphosphonates (BPs), bone targeted drugs that disrupt osteoclast function, are routinely used to treat complications of bone metastasis. Studies in preclinical models of cancer have shown that BPs reduce skeletal tumor burden and increase survival. Similarly, we observed in the present study that administration of the Nitrogen-containing BP (N-BP), zoledronic acid (ZA) to osteolytic tumor-bearing Tax+ mice beginning at 6 months of age led to resolution of radiographic skeletal lesions. N-BPs inhibit farnesyl diphosphate (FPP) synthase, thereby inhibiting protein prenylation and causing cellular toxicity. We found that ZA decreased Tax+ tumor and B16 melanoma viability and caused the accumulation of unprenylated Rap1a proteins in vitro. However, it is presently unclear whether N-BPs exert anti-tumor effects in bone independent of inhibition of osteoclast (OC) function in vivo. Therefore, we evaluated the impact of treatment with ZA on B16 melanoma bone tumor burden in irradiated mice transplanted with splenic cells from src(-/-) mice, which have non-functioning OCs. OC-defective mice treated with ZA demonstrated a significant 88% decrease in tumor growth in bone compared to vehicle-treated OC-defective mice. These data support an osteoclast-independent role for N-BP therapy in bone metastasis.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Difosfonatos/farmacologia , Imidazóis/farmacologia , Osteoclastos/patologia , Animais , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difosfonatos/administração & dosagem , Ativação Enzimática/efeitos dos fármacos , Geraniltranstransferase/metabolismo , Imidazóis/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Metástase Neoplásica/prevenção & controle , Osteoclastos/efeitos dos fármacos , Prenilação de Proteína/efeitos dos fármacos , Ácido Zoledrônico
11.
Cancer Res ; 69(7): 3196-204, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19276363

RESUMO

CD47, also called integrin-associated protein, plays a critical role in the innate immune response and is an atypical member of the immunoglobulin superfamily that interacts with and activates beta3 integrins. beta3 integrin(-/-) mice have defective platelet and osteoclast function and are protected from bone metastasis. The role of CD47 in skeletal homeostasis and bone metastasis has not been described. CD47(-/-) mice had increased bone mass and defective osteoclast function in vivo. Although the number of functional osteoclasts formed by differentiating CD47(-/-) bone marrow macrophages was decreased, high doses of RANKL rescued differentiation and function of CD47(-/-) osteoclasts ex vivo and rescued the osteoclast defect in CD47(-/-) mice. Inhibition of nitric oxide (NO) synthase, which is expressed at higher levels in CD47(-/-) osteoclasts, also rescued the osteoclast defect in CD47(-/-) cells. We then examined the consequences of this osteoclast defect in bone metastasis. In a model of tumor metastasis to bone, bone tumor burden was decreased in the CD47(-/-) mice compared with wild-type (WT) controls, with no decrease in s.c. tumor growth in CD47(-/-) mice. There was decreased tumor-associated bone destruction in the CD47(-/-) mice compared with WT controls, consistent with a defect in osteoclast function that was not rescued by the presence of tumor. Our data show that CD47 regulates osteoclastogenesis, in part, via regulation of NO production, and its disruption leads to a decrease in tumor bone metastasis. CD47 is a novel therapeutic target to strengthen bone mass and diminish metastatic tumor growth in bone.


Assuntos
Neoplasias Ósseas/secundário , Antígeno CD47/metabolismo , Melanoma Experimental/patologia , Animais , Neoplasias Ósseas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Humanos , Integrina beta3/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/secundário , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Óxido Nítrico Sintase/antagonistas & inibidores , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/patologia , Ligante RANK/farmacologia
12.
J Biol Chem ; 284(7): 4658-66, 2009 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-19059914

RESUMO

Interferon-gamma (IFN-gamma) has been shown to enhance anti-tumor immunity and inhibit the formation of bone-resorbing osteoclasts. We evaluated the role of IFN-gamma in bone metastases, tumor-associated bone destruction, and hypercalcemia in human T cell lymphotrophic virus type 1-Tax transgenic mice. Compared with Tax(+)IFN-gamma(+/+) mice, Tax(+)IFN-gamma(-/-) mice developed increased osteolytic bone lesions and soft tissue tumors, as well as increased osteoclast formation and activity. In vivo administration of IFN-gamma to tumor-bearing Tax(+)IFN-gamma(-/-) mice prevented new tumor development and resulted in decreased bromodeoxyuridine uptake by established tumors. In vitro, IFN-gamma directly decreased the viability of Tax(+) tumor cells through inhibition of proliferation, suppression of ERK phosphorylation, and induction of apoptosis and caspase 3 cleavage. IFN-gamma also inhibited macrophage colonystimulating factor-mediated proliferation and survival of osteoclast progenitors in vitro. Administration of IFN-gamma to C57BL/6 mice decreased Tax(+) tumor growth and prevented tumor-associated bone loss and hypercalcemia. In contrast, IFN-gamma treatment failed to protect IFN-gammaR1(-/-) mice from Tax(+) tumor-induced skeletal complications, despite decreasing tumor growth. These data demonstrate that IFN-gamma suppressed tumor-induced bone loss and hypercalcemia in Tax(+) mice by inhibiting both Tax(+) tumor cell growth and host-induced osteolysis. These data suggest a protective role for IFN-gamma in patients with bone metastases and hypercalcemia of malignancy.


Assuntos
Neoplasias Ósseas/metabolismo , Reabsorção Óssea/metabolismo , Vírus Linfotrópico T Tipo 1 Humano , Interferon gama/farmacologia , Osteoclastos/metabolismo , Neoplasias de Tecidos Moles/metabolismo , Animais , Neoplasias Ósseas/complicações , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Reabsorção Óssea/etiologia , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Reabsorção Óssea/prevenção & controle , Produtos do Gene tax/genética , Produtos do Gene tax/metabolismo , Humanos , Hipercalcemia/tratamento farmacológico , Hipercalcemia/etiologia , Hipercalcemia/genética , Hipercalcemia/metabolismo , Hipercalcemia/patologia , Interferon gama/genética , Interferon gama/metabolismo , Camundongos , Camundongos Knockout , Metástase Neoplásica , Osteoclastos/patologia , Neoplasias de Tecidos Moles/complicações , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/patologia
13.
Blood ; 106(13): 4294-302, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16118323

RESUMO

One in 20 carriers of human T-cell leukemia virus type 1 (HTLV-1) will develop adult T-cell leukemia/lymphoma (ATL), a disease frequently associated with hypercalcemia, bone destruction, and a fatal course refractory to current therapies. Overexpression of the HTLV-1-encoded Tax oncoprotein under the human granzyme B promoter causes large granular lymphocytic leukemia/lymphomas in mice. We found that Tax+ mice spontaneously developed hypercalcemia, high-frequency osteolytic bone metastases, and enhanced osteoclast activity. We evaluated Tax tumors for the production of osteoclast-activating factors. Purification of Tax+ tumor cells and nonmalignant tumor-infiltrating lymphocytes demonstrated that each of these populations expressed transcripts for distinct osteoclast-activating factors. We then evaluated the effect of osteoclast inhibition on tumor formation. Mice doubly transgenic for Tax and the osteoclast inhibitory factor, osteoprotegerin, were protected from osteolytic bone disease and developed fewer soft-tissue tumors. Likewise, osteoclast inhibition with bone-targeted zoledronic acid protected Tax+ mice from bone and soft-tissue tumors and prolonged survival. Tax+ mice represent the first animal model of high-penetrance spontaneous osteolytic bone metastasis and underscore the critical role of nonmalignant host cells recruited by tumor cells in the process of cancer progression and metastasis.


Assuntos
Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Produtos do Gene tax/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/genética , Osteoclastos/metabolismo , Osteoclastos/patologia , Animais , Densidade Óssea/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica , Produtos do Gene tax/genética , Hipercalcemia/genética , Hipercalcemia/metabolismo , Hipercalcemia/patologia , Interleucina-6/biossíntese , Interleucina-6/genética , Linfócitos/metabolismo , Linfocinas/genética , Linfocinas/metabolismo , Camundongos , Camundongos Transgênicos , Organofosfonatos/farmacologia , Osteoclastos/efeitos dos fármacos
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