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1.
Cell ; 184(15): 3998-4015.e19, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34157302

RESUMO

Foxp3+ T regulatory (Treg) cells promote immunological tumor tolerance, but how their immune-suppressive function is regulated in the tumor microenvironment (TME) remains unknown. Here, we used intravital microscopy to characterize the cellular interactions that provide tumor-infiltrating Treg cells with critical activation signals. We found that the polyclonal Treg cell repertoire is pre-enriched to recognize antigens presented by tumor-associated conventional dendritic cells (cDCs). Unstable cDC contacts sufficed to sustain Treg cell function, whereas T helper cells were activated during stable interactions. Contact instability resulted from CTLA-4-dependent downregulation of co-stimulatory B7-family proteins on cDCs, mediated by Treg cells themselves. CTLA-4-blockade triggered CD28-dependent Treg cell hyper-proliferation in the TME, and concomitant Treg cell inactivation was required to achieve tumor rejection. Therefore, Treg cells self-regulate through a CTLA-4- and CD28-dependent feedback loop that adjusts their population size to the amount of local co-stimulation. Its disruption through CTLA-4-blockade may off-set therapeutic benefits in cancer patients.


Assuntos
Antígeno CTLA-4/metabolismo , Retroalimentação Fisiológica , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Antígenos CD28/metabolismo , Proliferação de Células , Células Dendríticas/imunologia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Interleucina-2/metabolismo , Ligantes , Linfonodos/metabolismo , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/metabolismo , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Microambiente Tumoral
2.
Exp Cell Res ; 400(2): 112490, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33484747

RESUMO

Tumor neovascularization may occur via both angiogenic and vasculogenic events. In order to investigate the vessel formation during tumor growth, we developed a novel experimental model that takes into account the differentiative and tumorigenic properties of Embryonic Stem cells (ESCs). Leukemia Inhibitory Factor-deprived murine ESCs were grafted on the top of the chick embryo chorionallantoic membrane (CAM) in ovo. Cell grafts progressively grew, forming a vascularized mass within 10 days. At this stage, the grafts are formed by cells with differentiative features representative of all three germ layers, thus originating teratomas, a germinal cell tumor. In addition, ESC supports neovascular events by recruiting host capillaries from surrounding tissue that infiltrates the tumor mass. Moreover, immunofluorescence studies demonstrate that perfused active blood vessels within the tumor are of both avian and murine origin because of the simultaneous occurrence of angiogenic and vasculogenic events. In conclusion, the chick embryo ESC/CAM-derived teratoma model may represent a useful approach to investigate both vasculogenic and angiogenic events during tumor growth and for the study of natural and synthetic modulators of the two processes.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/patologia , Neovascularização Patológica , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/fisiologia , Teratoma/irrigação sanguínea , Teratoma/patologia , Animais , Embrião de Galinha , Membrana Corioalantoide , Células-Tronco Embrionárias/metabolismo , Camundongos , Camundongos Knockout , Teratoma/metabolismo
3.
Int J Mol Sci ; 23(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163075

RESUMO

Gremlin-1 is a secreted cystine-knot protein that acts as an antagonist of bone morphogenetic proteins (BMPs), and as a ligand of heparin and the vascular endothelial growth factor receptor 2 (VEGFR2), thus regulating several physiological and pathological processes, including embryonic development, tissue fibrosis and cancer. Gremlin-1 exerts all these biological activities only in its homodimeric form. Here, we propose a multi-step approach for the expression and purification of homodimeric, fully active, histidine-tagged recombinant gremlin-1, using mammalian HEK293T cells. Ion metal affinity chromatography (IMAC) of crude supernatant followed by heparin-affinity chromatography enables obtaining a highly pure recombinant dimeric gremlin-1 protein, exhibiting both BMP antagonist and potent VEGFR2 agonist activities.


Assuntos
Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Cromatografia de Afinidade/métodos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Recombinantes/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/agonistas , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/isolamento & purificação , Proteínas Recombinantes/genética
4.
Urban Ecosyst ; : 1-11, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36532698

RESUMO

Humans are transforming natural habitats into managed urban green areas and impervious surfaces at an unprecedented pace. Yet the effects of human presence per se on animal life-history traits are rarely tested. This is particularly true in cities, where human presence is often indissociable from urbanisation itself. The onset of the SARS-CoV-2 outbreak, along with the resulting lockdown restrictions, offered a unique, "natural experiment" to investigate wildlife responses to a sudden reduction in human activity. We analysed four years of avian breeding data collected in a European capital city to test whether lockdown measures altered nestbox occupancy and life-history traits in terms of egg laying date, incubation duration and clutch size in two urban adapters: great tits (Parus major) and blue tits (Cyanistes caeruleus). Lockdown measures, which modulated human presence, did not influence any of the life-history traits investigated. In contrast, the interaction between year and tree cover, a distinct ecological attribute of the urban space, was positively associated with clutch size, a key avian life-history and reproductive trait. This highlights the importance of inter-year variation and habitat quality over human activity on urban wildlife reproduction. We discuss our results in the light of other urban wildlife studies carried out during the pandemic, inviting the scientific community to carefully interpret all lockdown-associated shifts in biological traits. Supplementary Information: The online version contains supplementary material available at 10.1007/s11252-022-01309-5.

5.
Neurobiol Dis ; 134: 104705, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31830525

RESUMO

Glioblastoma (GBM) is the most malignant brain tumor of adults and is characterized by extensive cell dissemination within the brain parenchyma and enhanced angiogenesis. Effective preclinical modeling of these key features suffers from several shortcomings. Aim of this study was to determine whether modulating the expression of extracellular matrix (ECM) modifiers in proneural (PN) and mesenchymal (MES) cancer stem cells (CSCs) and in conventional glioma cell lines (GCLs) might improve tumor invasion and vascularization. To this end, we selected secreted, acidic and rich in cysteine-like 1 (SPARCL1) as a potential mediator of ECM remodeling in GBM. SPARCL1 transcript and protein expression was assessed in PN and MES CSCs as well as GCLs, in their xenografts and in patient-derived specimens by qPCR, WB and IHC. SPARCL1 expression was then enforced in both CSCs and GCLs by lentiviral-based transduction. The effect of SPARCL1 gain-of-function on microvascular proliferation, microglia activation and advanced imaging features was tested in intracranial xenografts by IHC and MRI and validated by chorioallantoic membrane (CAM) assays. SPARCL1 expression significantly enhanced the infiltrative and neoangiogenic features of PN and MES CSC/GCL-induced tumors, with the concomitant activation of inflammatory responses associated with the tumor microenvironment, thus resulting in experimental GBMs that reproduced both the parenchymal infiltration and the increased microvascular density, typical of GBM. Overall, these results indicate that SPARCL1 overexpression might be instrumental for the generation of CSC-derived preclinical models of GBM in which the main pathognomonic hallmarks of GBMs are retrievable, making them suitable for effective preclinical testing of therapeutics.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Glioblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neovascularização Patológica/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Feminino , Xenoenxertos , Humanos , Camundongos , Microglia/metabolismo
6.
Angiogenesis ; 23(3): 357-369, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32152757

RESUMO

N-formyl peptide receptors (FPRs) are G protein-coupled receptors involved in the recruitment and activation of immune cells in response to pathogen-associated molecular patterns. Three FPRs have been identified in humans (FPR1-FPR3), characterized by different ligand properties, biological function and cellular distribution. Recent findings from our laboratory have shown that the peptide BOC-FLFLF (L-BOC2), related to the FPR antagonist BOC2, acts as an angiogenesis inhibitor by binding to various angiogenic growth factors, including vascular endothelial growth factor-A165 (VEGF). Here we show that the all-D-enantiomer of L-BOC2 (D-BOC2) is devoid of any VEGF antagonist activity. At variance, D-BOC2, as well as the D-FLFLF and succinimidyl (Succ)-D-FLFLF (D-Succ-F3) D-peptide variants, is endowed with a pro-angiogenic potential. In particular, the D-peptide D-Succ-F3 exerts a pro-angiogenic activity in a variety of in vitro assays on human umbilical vein endothelial cells (HUVECs) and in ex vivo and in vivo assays in chick and zebrafish embryos and adult mice. This activity is related to the capacity of D-Succ-F3 to bind FRP3 expressed by HUVECs. Indeed, the effects exerted by D-Succ-F3 on HUVECs are fully suppressed by the G protein-coupled receptor inhibitor pertussis toxin, the FPR2/FPR3 antagonist WRW4 and by an anti-FPR3 antibody. A similar inhibition was observed following WRW4-induced FPR3 desensitization in HUVECs. Finally, D-Succ-F3 prevented the binding of the anti-FPR3 antibody to the cell surface of HUVECs. In conclusion, our data demonstrate that the angiogenic activity of D-Succ-F3 is due to the engagement and activation of FPR3 expressed by endothelial cells, thus shedding a new light on the biological function of this chemoattractant receptor.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Oligopeptídeos/farmacologia , Receptores de Formil Peptídeo , Humanos , Oligopeptídeos/síntese química , Oligopeptídeos/química , Receptores de Formil Peptídeo/agonistas , Receptores de Formil Peptídeo/metabolismo
7.
Angiogenesis ; 22(4): 521-533, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31363885

RESUMO

The Bone Morphogenetic Protein 4 (BMP4) regulates multiple biological processes, including vascular development and angiogenesis. Here, we investigated the role of Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) in mediating the angiogenic activity of BMP4. BMP4 induces a rapid relocation and phosphorylation of VEGFR2 on the endothelial cell membrane. These effects occur in the absence of a direct interaction of BMP4 and/or BMP receptors with VEGFR2. At variance, BMP4, by interacting with the BMPRI-II hetero-complex, induces c-Src phosphorylation which, in turn, activates VEGFR2, leading to an angiogenic response. Accordingly, the BMPR inhibitor dorsomorphin prevents c-Src activation and specific inhibition of c-Src significantly reduces downstream VEGFR2 phosphorylation and the angiogenic activity exerted by BMP4 in a chick embryo chorioallantoic membrane assay. Together, our data indicate that the pro-angiogenic activity exerted by BMP4 in endothelial cells is mediated by a BMPR-mediated intracellular transactivation of VEGFR2 via c-Src.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Neovascularização Fisiológica , Transdução de Sinais , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Proteína Tirosina Quinase CSK/metabolismo , Bovinos , Embrião de Galinha , Humanos , Ativação Transcricional
8.
Angiogenesis ; 21(1): 47-59, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29030736

RESUMO

The peptides N-tert-butyloxycarbonyl-Phe-Leu-Phe-Leu-Phe (BOC2) and BOC-Met-Leu-Phe (BOC1) are widely used antagonists of formyl peptide receptors (FPRs), BOC2 acting as an FPR1/FPR2 antagonist whereas BOC1 inhibits FPR1 only. Extensive investigations have been performed by using these FPR antagonists as a tool to assess the role of FPRs in physiological and pathological conditions. Based on previous observations from our laboratory, we assessed the possibility that BOC2 may exert also a direct inhibitory effect on the angiogenic activity of vascular endothelial growth factor-A (VEGF-A). Our data demonstrate that BOC2, but not BOC1, inhibits the angiogenic activity of heparin-binding VEGF-A165 with no effect on the activity of the non-heparin-binding VEGF-A121 isoform. Endothelial cell-based bioassays, surface plasmon resonance analysis, and computer modeling indicate that BOC2 may interact with the heparin-binding domain of VEGF-A165, thus competing for heparin interaction and preventing the binding of VEGF-A165 to tyrosine kinase receptor VEGFR2, its phosphorylation and downstream signaling. In addition, BOC2 inhibits the interaction of a variety of heparin-binding angiogenic growth factors with heparin, including fibroblast growth factor 2 (FGF2) whose angiogenic activity is blocked by the compound. Accordingly, BOC2 suppresses the angiogenic potential of human tumor cell lines that co-express VEGF-A and FGF2. Thus, BOC2 appears to act as a novel multi-heparin-binding growth factor antagonist. These findings caution about the interpretation of FPR-focusing experimental data obtained with this compound and set the basis for the design of novel BOC2-derived, FPR independent multi-target angiogenesis inhibitors.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Oligopeptídeos , Fator A de Crescimento do Endotélio Vascular , Animais , Células CHO , Bovinos , Linhagem Celular Tumoral , Embrião de Galinha , Cricetulus , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Neovascularização Fisiológica/fisiologia , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Receptores de Formil Peptídeo/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ressonância de Plasmônio de Superfície , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Peixe-Zebra
9.
Diabetologia ; 60(4): 719-728, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28083635

RESUMO

AIMS/HYPOTHESIS: Angiogenesis and inflammation characterise proliferative diabetic retinopathy (PDR), a major complication of diabetes mellitus. However, the impact of inflammation on the pathogenesis of PDR neovascularisation has not been elucidated. Here, we assessed the capacity of PDR vitreous fluid to induce pro-angiogenic/proinflammatory responses in endothelium and the contribution of the inflammation-related pattern recognition N-formyl peptide receptors (FPRs) in mediating these responses. METHODS: Pooled and individual pars plana vitrectomy-derived PDR vitreous fluid ('PDR vitreous') samples were assessed in endothelial cell proliferation, motility, sprouting and morphogenesis assays, and for the capacity to induce proinflammatory transcription factor activation, reactive oxygen species production, intercellular junction disruption and leucocyte-adhesion molecule upregulation in these cells. In vivo, the pro-angiogenic/proinflammatory activity of PDR vitreous was tested in murine Matrigel plug and chick embryo chorioallantoic membrane (CAM) assays. Finally, the FPR inhibitors Boc-Phe-Leu-Phe-Leu-Phe (Boc-FLFLF) and Ac-L-Arg-Aib-L-Arg-L-Cα(Me)Phe-NH2 tetrapeptide (UPARANT) were evaluated for their capacity to affect the biological responses elicited by PDR vitreous. RESULTS: PDR vitreous activates a pro-angiogenic/proinflammatory phenotype in endothelial cells. Accordingly, PDR vitreous triggers a potent angiogenic/inflammatory response in vivo. Notably, the different capacity of individual PDR vitreous samples to induce neovessel formation in the CAM correlates with their ability to recruit infiltrating CD45+ cells. Finally, the FPR inhibitor Boc-FLFLF and the novel FPR antagonist UPARANT inhibit neovessel formation and inflammatory responses triggered by PDR vitreous in the CAM assay. CONCLUSIONS/INTERPRETATION: This study provides evidence that inflammation mediates the angiogenic activity of PDR vitreous and paves the way for the development of FPR-targeting anti-inflammatory/anti-angiogenic approaches for PDR therapy.


Assuntos
Retinopatia Diabética/metabolismo , Inflamação/metabolismo , Receptores de Formil Peptídeo/metabolismo , Corpo Vítreo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular , Retinopatia Diabética/imunologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neovascularização Patológica/imunologia , Neovascularização Patológica/metabolismo
10.
Arterioscler Thromb Vasc Biol ; 35(10): 2161-71, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26293466

RESUMO

OBJECTIVE: During neovessel formation, angiogenic growth factors associate with the extracellular matrix. These immobilized factors represent a persistent stimulus for the otherwise quiescent endothelial cells (ECs), driving directional EC migration and proliferation and leading to new blood vessel growth. Vascular endothelial growth factor receptor 2 (VEGFR2) is the main mediator of angiogenesis. Although VEGFR2 signaling has been deeply characterized, little is known about its subcellular localization during neovessel formation. Aim of this study was the characterization and molecular determinants of activated VEGFR2 localization in ECs during neovessel formation in response to matrix-immobilized ligand. APPROACH AND RESULTS: Here we demonstrate that ECs stimulated by extracellular matrix-associated gremlin, a noncanonical VEGFR2 ligand, are polarized and relocate the receptor in close contact with the angiogenic factor-enriched matrix both in vitro and in vivo. GM1 (monosialotetrahexosylganglioside)-positive planar lipid rafts, ß3 integrin receptors, and the intracellular signaling transducers focal adhesion kinase and RhoA (Ras homolog gene family, member A) cooperate to promote VEGFR2 long-term polarization and activation. CONCLUSIONS: A ligand anchored to the extracellular matrix induces VEGFR2 polarization in ECs. Long-lasting VEGFR2 relocation is closely dependent on lipid raft integrity and activation of ß3 integrin pathway. The study of the endothelial responses to immobilized growth factors may offer insights into the angiogenic process in physiological and pathological conditions, including cancer, and for a better engineering of synthetic tissue scaffolds to blend with the host vasculature.


Assuntos
Endotélio Vascular/metabolismo , Integrina beta3/metabolismo , Neovascularização Fisiológica/fisiologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Humanos , Sensibilidade e Especificidade , Transdução de Sinais
11.
Arterioscler Thromb Vasc Biol ; 34(1): 136-45, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24233491

RESUMO

OBJECTIVE: Angiogenesis and inflammation are closely related processes. Gremlin is a novel noncanonical vascular endothelial growth factor receptor-2 (VEGFR2) ligand that induces a proangiogenic response in endothelial cells (ECs). Here, we investigated the role of the cyclic adenosine monophosphate-response element (CRE)-binding protein (CREB) in mediating the proinflammatory and proangiogenic responses of ECs to gremlin. APPROACH AND RESULTS: Gremlin induces a proinflammatory response in ECs, leading to reactive oxygen species and cyclic adenosine monophosphate production and the upregulation of proinflammatory molecules involved in leukocyte extravasation, including chemokine (C-C motif) ligand-2 (Ccl2) and Ccl7, chemokine (C-X-C motif) ligand-1 (Cxcl1), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1). Accordingly, gremlin induces the VEGFR2-dependent phosphorylation, nuclear translocation, and transactivating activity of CREB in ECs. CREB activation mediates the early phases of the angiogenic response to gremlin, including stimulation of EC motility and permeability, and leads to monocyte/macrophage adhesion to ECs and their extravasation. All these effects are inhibited by EC transfection with a dominant-negative CREB mutant or with a CREB-binding protein-CREB interaction inhibitor that competes for CREB/CRE binding. Also, both recombinant gremlin and gremlin-expressing tumor cells induce proinflammatory/proangiogenic responses in vivo that are suppressed by the anti-inflammatory drug hydrocortisone. Similar effects were induced by the canonical VEGFR2 ligand VEGF-A165. CONCLUSIONS: Together, the results underline the tight cross-talk between angiogenesis and inflammation and demonstrate a crucial role of CREB activation in the modulation of the VEGFR2-mediated proinflammatory/proangiogenic response of ECs to gremlin.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neovascularização Fisiológica , Transporte Ativo do Núcleo Celular , Inibidores da Angiogênese/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Permeabilidade Capilar , Adesão Celular , Movimento Celular , Quimiocina CCL2/metabolismo , Quimiocina CCL7/metabolismo , Quimiocina CXCL1/metabolismo , Embrião de Galinha , Técnicas de Cocultura , Meios de Cultivo Condicionados/metabolismo , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Citocinas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Endoteliais da Veia Umbilical Humana/imunologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hidrocortisona/farmacologia , Inflamação/genética , Inflamação/imunologia , Inflamação/prevenção & controle , Molécula 1 de Adesão Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Ligantes , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neovascularização Fisiológica/efeitos dos fármacos , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
12.
J Pathol ; 230(2): 228-38, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23424081

RESUMO

Fibroblast growth factors (FGFs) exert autocrine/paracrine functions in prostate cancer by stimulating angiogenesis and tumour growth. Here dihydrotestosterone (DHT) up-regulates FGF2 and FGF8b production in murine TRAMP-C2 prostate cancer cells, activating a FGF-dependent autocrine loop of stimulation. The soluble pattern recognition receptor long pentraxin-3 (PTX3) acts as a natural FGF antagonist that binds FGF2 and FGF8b via its N-terminal domain. We demonstrate that recombinant PTX3 protein and the PTX3-derived pentapeptide Ac-ARPCA-NH2 abolish the mitogenic response of murine TRAMP-C2 cells and human LNCaP prostate cancer cells to DHT and FGFs. Also, PTX3 hampers the angiogenic activity of DHT-activated TRAMP-C2 cells on the chick embryo chorioallantoic membrane (CAM). Accordingly, human PTX3 overexpression inhibits the mitogenic activity exerted by DHT or FGFs on hPTX3_TRAMP-C2 cell transfectants and their angiogenic activity. Also, hPTX3_TRAMP-C2 cells show a dramatic decrease of their angiogenic and tumourigenic potential when grafted in syngeneic or immunodeficient athymic male mice. A similar inhibitory effect is observed when TRAMP-C2 cells overexpress only the FGF-binding N-terminal PTX3 domain. In keeping with the anti-tumour activity of PTX3 in experimental prostate cancer, immunohistochemical analysis of prostate needle biopsies from primary prostate adenocarcinoma patients shows that parenchymal PTX3 expression, abundant in basal cells of normal glands, is lost in high-grade prostatic intraepithelial neoplasia and in invasive tumour areas. These results identify PTX3 as a potent FGF antagonist endowed with anti-angiogenic and anti-neoplastic activity in prostate cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Proteína C-Reativa/farmacologia , Próstata/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Componente Amiloide P Sérico/farmacologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Linhagem Celular Tumoral , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Mitógenos/antagonistas & inibidores , Neovascularização Fisiológica/efeitos dos fármacos , Próstata/metabolismo , Próstata/patologia , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Recombinantes/farmacologia
13.
Sci Transl Med ; 16(736): eadf9874, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416843

RESUMO

Targeting aromatase deprives ER+ breast cancers of estrogens and is an effective therapeutic approach for these tumors. However, drug resistance is an unmet clinical need. Lipidomic analysis of long-term estrogen-deprived (LTED) ER+ breast cancer cells, a model of aromatase inhibitor resistance, revealed enhanced intracellular lipid storage. Functional metabolic analysis showed that lipid droplets together with peroxisomes, which we showed to be enriched and active in the LTED cells, controlled redox homeostasis and conferred metabolic adaptability to the resistant tumors. This reprogramming was controlled by acetyl-CoA-carboxylase-1 (ACC1), whose targeting selectively impaired LTED survival. However, the addition of branched- and very long-chain fatty acids reverted ACC1 inhibition, a process that was mediated by peroxisome function and redox homeostasis. The therapeutic relevance of these findings was validated in aromatase inhibitor-treated patient-derived samples. Last, targeting ACC1 reduced tumor growth of resistant patient-derived xenografts, thus identifying a targetable hub to combat the acquisition of estrogen independence in ER+ breast cancers.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/uso terapêutico , Peroxissomos/metabolismo , Peroxissomos/patologia , Acetil-CoA Carboxilase , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Linhagem Celular Tumoral , Estrogênios/metabolismo , Resistencia a Medicamentos Antineoplásicos
14.
Angiogenesis ; 16(1): 235-43, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23053782

RESUMO

α(v)ß(3) integrin modulates pro-angiogenic endothelial cell (EC) responses following vascular endothelial growth factor receptor-2 (VEGFR2) engagement. The bone morphogenic protein antagonist gremlin is a novel non-canonical VEGFR2 ligand that promotes the acquisition of a pro-angiogenic phenotype in ECs. Here we investigated the role of α(v)ß(3) and extracellular matrix components on EC activation induced by gremlin. Gremlin triggers VEGFR2 phosphorylation and cell motility in ECs adherent to the α(v)ß(3) ligand fibrinogen but not in ECs adherent to type-I collagen or fibronectin. Also, gremlin and VEGF-A stimulate the formation of VEGFR2/α(v)ß(3) integrin complexes as shown by co-immunoprecipitation experiments and fluorescence resonance energy transfer analysis of ß(3)-ECFP/VEGFR2-EYFP co-transfected ECs. Accordingly, anti-ß(3) antibodies block the angiogenic activity exerted by gremlin or VEGF-A in vitro, ex vivo and in vivo. The results demonstrate a non-redundant role for α(v)ß(3) in gremlin-induced angiogenesis and emphasize its contribution to the formation of functional multi-molecular VEGFR2 complexes responsible for the neovascularization events triggered by canonical and non-canonical pro-angiogenic VEGFR2 ligands.


Assuntos
Integrina alfaVbeta3/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Galinhas , Citocinas , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Células MCF-7 , Camundongos , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
15.
Methods Mol Biol ; 2572: 181-189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36161417

RESUMO

Embryonic stem cells give rise to teratomas when injected in vivo in experimental animal models. The characterization, the manipulation, and the breaking off of this specific characteristic are doubtlessly the last frontier for the applications of stem cells in translational medicine. Moreover, the urgency to adapt to new scientific demands drives the researcher to find alternative and faster models for testing the teratogenic properties of embryonic stem cells. Here, we compare the emerging model of the chick embryo chorioallantoic membrane (CAM) to the murine model, which represents the gold standard procedure for teratogenesis.


Assuntos
Teratoma , Animais , Embrião de Galinha , Membrana Corioalantoide , Células-Tronco Embrionárias , Camundongos
16.
Cytokine Growth Factor Rev ; 69: 61-72, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35953434

RESUMO

Adipose tissue (AT) is a highly active and plastic endocrine organ. It secretes numerous soluble molecules known as adipokines, which act locally to AT control the remodel and homeostasis or exert pleiotropic functions in different peripheral organs. Aberrant production or loss of certain adipokines contributes to AT dysfunction associated with metabolic disorders, including obesity. The AT plasticity is strictly related to tissue vascularization. Angiogenesis supports the AT expansion, while regression of blood vessels is associated with AT hypoxia, which in turn mediates tissue inflammation, fibrosis and metabolic dysfunction. Several adipokines can regulate endothelial cell functions and are endowed with either pro- or anti-angiogenic properties. Here we address the role of adipokines in the regulation of angiogenesis. A better understanding of the link between adipokines and angiogenesis will open the way for novel therapeutic approaches to treat obesity and metabolic diseases.


Assuntos
Adipocinas , Tecido Adiposo , Doenças Metabólicas , Humanos , Adipocinas/metabolismo , Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/metabolismo , Inflamação/metabolismo , Doenças Metabólicas/metabolismo , Obesidade/metabolismo , Neovascularização Fisiológica/fisiologia
17.
Biochim Biophys Acta Gen Subj ; 1867(12): 130470, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37778450

RESUMO

The activation loop (A-loop) of kinases, a key regulatory region, is recurrently mutated in several kinase proteins in cancer resulting in dysregulated kinase activity and response to kinase inhibitors. FGFR1 receptor tyrosine kinase represents an important oncogene and therapeutic target for solid and hematological tumors. Here we investigate the biochemical and molecular effects of D647N mutation lying in the A-loop of FGFR1. When expressed in normal and tumoral in vitro cell models, FGFR1D647N is phosphorylated also in the absence of ligands, and this is accompanied by the activation of intracellular signaling. The expression of FGFR1D647N significantly increases single and collective migration of cancer cells in vitro and in vivo, when compared to FGFR1WT. FGFR1D647N expression exacerbates the aggressiveness of cancer cells, increasing their invasiveness in vitro and augmenting their pro-angiogenic capacity in vivo. Remarkably, the D647N mutation significantly increases the sensitivity of FGFR1 to the ATP-competitive inhibitor Erdafitinib suggesting the possibility that this mutation could become a specific target for the development of new inhibitors. Although further efforts are warranted for an exhaustive description of the activation mechanisms, for the identification of more specific inhibitors and for confirming the clinical significance of mutated FGFR1D647N, overall our data demonstrate that the D647N substitution of FGFR1 is a novel pro-oncogenic activating mutation of the receptor that, when found in cancer patients, may anticipate good response to erdafitinib treatment.


Assuntos
Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Transdução de Sinais , Humanos , Ligantes , Linhagem Celular Tumoral , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Fosforilação , Mutação
18.
Sci Total Environ ; 838(Pt 2): 156034, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35595141

RESUMO

Solid waste pollution (garbage discarded by humans, such as plastic, metal, paper) has received increased attention given its importance as a global threat to biodiversity. Recent studies highlight how animals incorporate anthropogenic materials into their life-cycle, for example in avian nest construction. While increasingly monitored in natural areas, the influence of solid waste pollution on wildlife has been seldom explored in the urban habitat. There is limited data on the relationship between anthropogenic solid waste pollution, nest design, and reproductive success in an urban context. We address this knowledge gap (i) by investigating the presence of environmental solid waste pollution in the breeding habitats of great tits Parus major and blue tits Cyanistes caeruleus reproducing in a gradient of urbanisation, and (ii) by quantifying (ii) the contribution of different anthropogenic materials in their nests. We further examine potential drivers of solid waste pollution by inferring three distinct properties of the urban space: environmental solid waste pollution on the ground, human presence, and the intensity of urbanisation (e.g impervious surfaces) in nestbox vicinity. Finally, (iii) we explore the relationship between anthropogenic nest materials and reproductive success. We found that environmental solid waste pollution was positively associated with human presence and urbanisation intensity. There was also a positive relationship between increased human presence and the amount of anthropogenic materials in great tit nests. Interestingly, in both species, anthropogenic nest materials covaried negatively with nest materials of animal origin (fur and feathers). We suggest that fur and feathers - key insulating materials in nest design - may be scarcer in areas with high levels of human presence, and are consequently replaced with anthropogenic nest materials. Finally, we report a negative relationship between anthropogenic nest materials and blue tit reproductive success, suggesting species-specific vulnerability of urban birds to solid waste pollution.


Assuntos
Passeriformes , Aves Canoras , Animais , Poluição Ambiental/análise , Fenótipo , Resíduos Sólidos
19.
Sci Total Environ ; 847: 157450, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35863574

RESUMO

Most research on urban avian ecology has focused on population- and community-level phenomena, whereas fewer studies have examined how urbanization affects individual behavioral responses to a sudden and novel stimulus, and how those translate to fitness. We measured between-individual variation in provisioning latency in two urban adapters - great tits and blue tits - in response to an infrared camera installed in the nestbox, encountered when offspring in the nest were at the peak of food demand (9-10-days old). For each nestbox, we quantified urbanization as intensity in human activity, distance to road and proportion of impervious surface area. In both species, provisioning latency increased closer to roads. Moreover, increased provisioning latency when exposed to a novel object was associated with higher reproductive success in great tits whose nestboxes were surrounded by high amounts of impervious surface. In contrast, increased provisioning latency was consistently associated with lower reproductive success in blue tits. Our results suggest that provisioning latency changes in relation to the environment surrounding the nest, and may be context- and species-specific when exposed to a novel stimulus, such as a novel object in the nest. To better understand the role of initial behavioral responses towards novelty across an individual's lifetime and, ultimately, its impact on fitness in the urban mosaic, further research explicitly testing different behavioral responses across the entire breeding cycle in wild model systems is needed.


Assuntos
Passeriformes , Aves Canoras , Animais , Adaptação Psicológica , Passeriformes/fisiologia , Reprodução , Aves Canoras/fisiologia , Urbanização
20.
Biochim Biophys Acta Mol Basis Dis ; 1868(2): 166313, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34826586

RESUMO

Fibroblast growth factor receptors (FGFRs) are recurrently altered by single nucleotide variants (SNVs) in many human cancers. The prevalence of SNVs in FGFRs depends on the cancer type. In some tumors, such as the urothelial carcinoma, mutations of FGFRs occur at very high frequency (up to 60%). Many characterized mutations occur in the extracellular or transmembrane domains, while fewer known mutations are found in the kinase domain. In this study, we performed a bioinformatics analysis to identify novel putative cancer driver or therapeutically actionable mutations of the kinase domain of FGFRs. To pinpoint those mutations that may be clinically relevant, we exploited the recurrence of alterations on analogous amino acid residues within the kinase domain (PK_Tyr_Ser-Thr) of different kinases as a predictor of functional impact. By exploiting MutationAligner and LowMACA bioinformatics resources, we highlighted novel uncharacterized mutations of FGFRs which recur in other protein kinases. By revealing unanticipated correspondence with known variants, we were able to infer their functional effects, as alterations clustering on similar residues in analogous proteins have a high probability to elicit similar effects. As FGFRs represent an important class of oncogenes and drug targets, our study opens the way for further studies to validate their driver and/or actionable nature and, in the long term, for a more efficacious application of precision oncology.


Assuntos
Carcinogênese/patologia , Mutação , Neoplasias/patologia , Inibidores de Proteínas Quinases/farmacologia , Receptores Proteína Tirosina Quinases/genética , Receptores de Fatores de Crescimento de Fibroblastos/genética , Sequência de Aminoácidos , Carcinogênese/genética , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fosforilação , Domínios Proteicos
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