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1.
Int J Mol Sci ; 25(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38732216

RESUMO

Aspartate ß-hydroxylase (ASPH) is a protein associated with malignancy in a wide range of tumors. We hypothesize that inhibition of ASPH activity could have anti-tumor properties in patients with head and neck cancer. In this study, we screened tumor tissues of 155 head and neck squamous cell carcinoma (HNSCC) patients for the expression of ASPH using immunohistochemistry. We used an ASPH inhibitor, MO-I-1151, known to inhibit the catalytic activity of ASPH in the endoplasmic reticulum, to show its inhibitory effect on the migration of SCC35 head and neck cancer cells in cell monolayers and in matrix-embedded spheroid co-cultures with primary cancer-associated fibroblast (CAF) CAF 61137 of head and neck origin. We also studied a combined effect of MO-I-1151 and HfFucCS, an inhibitor of invasion-blocking heparan 6-O-endosulfatase activity. We found ASPH was upregulated in HNSCC tumors compared to the adjacent normal tissues. ASPH was uniformly high in expression, irrespective of tumor stage. High expression of ASPH in tumors led us to consider it as a therapeutic target in cell line models. ASPH inhibitor MO-I-1151 had significant effects on reducing migration and invasion of head and neck cancer cells, both in monolayers and matrix-embedded spheroids. The combination of the two enzyme inhibitors showed an additive effect on restricting invasion in the HNSCC cell monolayers and in the CAF-containing co-culture spheroids. We identify ASPH as an abundant protein in HNSCC tumors. Targeting ASPH with inhibitor MO-I-1151 effectively reduces CAF-mediated cellular invasion in cancer cell models. We propose that the additive effect of MO-I-1151 with HfFucCS, an inhibitor of heparan 6-O-endosulfatases, on HNSCC cells could improve interventions and needs to be further explored.


Assuntos
Movimento Celular , Neoplasias de Cabeça e Pescoço , Invasividade Neoplásica , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Feminino , Pessoa de Meia-Idade , Oxigenases de Função Mista/metabolismo , Masculino , Técnicas de Cocultura , Idoso , Proteínas de Ligação ao Cálcio , Proteínas de Membrana , Proteínas Musculares
2.
Res Sq ; 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36798383

RESUMO

DNA sequence accounts for the majority of disease heritability, including cancer. Yet, not all familial cancer cases can be explained by genetic factors. It is becoming clear that environmentally induced epigenetic inheritance occurs and that the progeny's traits can be shaped by parental environmental experiences. In humans, epidemiological studies have implicated environmental toxicants, such as the pesticide DDT, in intergenerational cancer development, including breast and childhood tumors. Here, we show that the female progeny of males exposed to DDT in the pre-conception period have higher susceptibility to developing aggressive tumors in mouse models of breast cancer. Sperm of DDT-exposed males exhibited distinct patterns of small non-coding RNAs, with an increase in miRNAs and a specific surge in miRNA-10b levels. Remarkably, embryonic injection of the entire sperm RNA load of DDT-exposed males, or synthetic miRNA-10b, recapitulated the tumor phenotypes observed in DDT offspring. Mechanistically, miR-10b injection altered the transcriptional profile in early embryos with enrichment of genes associated with cell differentiation, tissue and immune system development. In adult DDT-derived progeny, transcriptional and protein analysis of mammary tumors revealed alterations in stromal and in immune system compartments. Our findings reveal a causal role for sperm RNAs in environmentally induced inheritance of cancer predisposition and, if confirmed in humans, this could help partially explain some of the "missing heritability" of breast, and other, malignancies.

4.
Int J Biol Sci ; 18(7): 2670-2682, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35541897

RESUMO

Retinoic acid receptor responder 1 (RARRES1) is among the most commonly methylated loci in multiple cancers. RARRES1 regulates mitochondrial and fatty acid metabolism, stem cell differentiation, and survival of immortalized cell lines in vitro. Here, we created constitutive Rarres1 knockout (Rarres1-/-) mouse models to study RARRES1 function in vivo. Rarres1-/- embryonic fibroblasts regulated tubulin glutamylation, cell metabolism, and survival, recapitulating RARRES1 function in immortalized cell lines. In two mouse strains, loss of Rarres1 led to a markedly increased dose-dependent incidence of follicular lymphoma (FL). Prior to lymphoma formation, Rarres1-/- B cells have compromised activation, maturation, differentiation into antibody-secreting plasma cells, and cell cycle progression. Rarres1 ablation increased B cell survival and led to activation of the unfolded protein response (UPR) and heat shock response (HSR). Rarres1 deficiency had differential effects on cellular metabolism, with increased bioenergetic capacity in fibroblasts, and minor effects on bioenergetics and metabolism in B cells. These findings reveal that RARRES1 is a bona fide tumor suppressor in vivo and the deletion in mice promotes cell survival, and reduces B cell differentiation with B cell autonomous and non-autonomous functions.


Assuntos
Genes Supressores de Tumor , Proteínas de Membrana , Animais , Diferenciação Celular/genética , Linhagem Celular , Metabolismo dos Lipídeos , Proteínas de Membrana/metabolismo , Camundongos
5.
Nat Commun ; 13(1): 2323, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484119

RESUMO

Adverse prognosis in Ewing sarcoma (ES) is associated with the presence of metastases, particularly in bone, tumor hypoxia and chromosomal instability (CIN). Yet, a mechanistic link between these factors remains unknown. We demonstrate that in ES, tumor hypoxia selectively exacerbates bone metastasis. This process is triggered by hypoxia-induced stimulation of the neuropeptide Y (NPY)/Y5 receptor (Y5R) pathway, which leads to RhoA over-activation and cytokinesis failure. These mitotic defects result in the formation of polyploid ES cells, the progeny of which exhibit high CIN, an ability to invade and colonize bone, and a resistance to chemotherapy. Blocking Y5R in hypoxic ES tumors prevents polyploidization and bone metastasis. Our findings provide evidence for the role of the hypoxia-inducible NPY/Y5R/RhoA axis in promoting genomic changes and subsequent osseous dissemination in ES, and suggest that targeting this pathway may prevent CIN and disease progression in ES and other cancers rich in NPY and Y5R.


Assuntos
Neoplasias Ósseas , Sarcoma de Ewing , Neoplasias Ósseas/genética , Instabilidade Cromossômica , Humanos , Hipóxia , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Receptores de Neuropeptídeo Y/genética , Receptores de Neuropeptídeo Y/metabolismo , Sarcoma de Ewing/patologia , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
6.
Front Cell Dev Biol ; 8: 627090, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33681186

RESUMO

Neuropeptide Y (NPY) has been implicated in the regulation of cellular motility under various physiological and pathological conditions, including cancer dissemination. Yet, the exact signaling pathways leading to these effects remain unknown. In a pediatric malignancy, neuroblastoma (NB), high NPY release from tumor tissue associates with metastatic disease. Here, we have shown that NPY stimulates NB cell motility and invasiveness and acts as a chemotactic factor for NB cells. We have also identified the Y5 receptor (Y5R) as the main NPY receptor mediating these actions. In NB tissues and cell cultures, Y5R is highly expressed in migratory cells and accumulates in regions of high RhoA activity and dynamic cytoskeleton remodeling. Y5R stimulation activates RhoA and results in Y5R/RhoA-GTP interactions, as shown by pull-down and proximity ligation assays, respectively. This is the first demonstration of the role for the NPY/Y5R axis in RhoA activation and the subsequent cytoskeleton remodeling facilitating cell movement. These findings implicate Y5R as a target in anti-metastatic therapies for NB and other cancers expressing this receptor.

7.
Lab Invest ; 100(1): 38-51, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31409888

RESUMO

Neuroblastoma (NB) is a pediatric tumor of the peripheral nervous system. Treatment of the disease represents an unsolved clinical problem, as survival of patients with aggressive form of NB remains below 50%. Despite recent identification of numerous potential therapeutic targets, clinical trials validating them are challenging due to the rarity of the disease and its high patient-to-patient heterogeneity. Hence, there is a need for the accurate preclinical models that would allow testing novel therapeutic approaches and prioritizing the clinical studies, preferentially in personalized way. Here, we propose using conditional reprogramming (CR) technology for rapid development of primary NB cell cultures that could become a new model for such tests. This newly established method allowed for indefinite propagation of normal and tumor cells of epithelial origin in an undifferentiated state by their culture in the presence of Rho-associated kinase (ROCK) inhibitor, Y-27632, and irradiated mouse feeder cells. Using a modification of this approach, we isolated cell lines from tumors arising in the TH-MYCN murine transgenic model of NB (CR-NB). The cells were positive for neuronal markers, including Phox2B and peripherin and consisted of two distinct populations: mesenchymal and adrenergic expressing corresponding markers of their specific lineage. This heterogeneity of the CR-NB cells mimicked the different tumor cell phenotypes in TH-MYCN tumor tissues. The CR-NB cells preserved anchorage-independent growth capability and were successfully passaged, frozen and biobanked. Further studies are required to determine the utility of this method for isolation of human NB cultures, which can become a novel model for basic, translational, and clinical research, including individualized drug testing.


Assuntos
Linhagem Celular Tumoral , Neuroblastoma/patologia , Animais , Biomarcadores/metabolismo , Técnicas de Reprogramação Celular , Humanos , Camundongos Transgênicos , Neoplasias Experimentais , Neuroblastoma/metabolismo , Fenótipo , Ratos
8.
Dis Model Mech ; 11(9)2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-29925537

RESUMO

Age-related macular degeneration (AMD) is the major cause of blindness in the elderly in developed countries and its prevalence is increasing with the aging population. AMD initially affects the retinal pigment epithelium (RPE) and gradually leads to secondary photoreceptor degeneration. Recent studies have associated mitochondrial damage with AMD, and we have observed mitochondrial and autophagic dysfunction and repressed peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α; also known as Ppargc1a) in native RPE from AMD donor eyes and their respective induced pluripotent stem cell-derived RPE. To further investigate the effect of PGC-1α repression, we have established a mouse model by feeding Pgc-1α+/- mice with a high-fat diet (HFD) and investigated RPE and retinal health. We show that when mice expressing lower levels of Pgc-1α are exposed to HFD, they present AMD-like abnormalities in RPE and retinal morphology and function. These abnormalities include basal laminar deposits, thickening of Bruch's membrane with drusen marker-containing deposits, RPE and photoreceptor degeneration, decreased mitochondrial activity, increased levels of reactive oxygen species, decreased autophagy dynamics/flux, and increased inflammatory response in the RPE and retina. Our study shows that Pgc-1α is important in outer retina biology and that Pgc-1α+/- mice fed with HFD provide a promising model to study AMD, opening doors for novel treatment strategies.


Assuntos
Dieta Hiperlipídica , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Animais , Antioxidantes/metabolismo , Autofagia , Membrana Basal/metabolismo , Membrana Basal/patologia , Corioide/irrigação sanguínea , Endotélio/patologia , Regulação da Expressão Gênica , Inflamação/patologia , Lipofuscina/metabolismo , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Drusas Retinianas/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/ultraestrutura
9.
Am J Pathol ; 186(11): 3040-3053, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27743558

RESUMO

Neuroblastoma (NB) is a pediatric malignant neoplasm of sympathoadrenal origin. Challenges in its management include stratification of this heterogeneous disease and a lack of both adequate treatments for high-risk patients and noninvasive biomarkers of disease progression. Our previous studies have identified neuropeptide Y (NPY), a sympathetic neurotransmitter expressed in NB, as a potential therapeutic target for these tumors by virtue of its Y5 receptor (Y5R)-mediated chemoresistance and Y2 receptor (Y2R)-mediated proliferative and angiogenic activities. The goal of this study was to determine the clinical relevance and utility of these findings. Expression of NPY and its receptors was evaluated in corresponding samples of tumor RNA, tissues, and sera from 87 patients with neuroblastic tumors and in tumor tissues from the TH-MYCN NB mouse model. Elevated serum NPY levels correlated with an adverse clinical presentation, poor survival, metastasis, and relapse, whereas strong Y5R immunoreactivity was a marker of angioinvasive tumor cells. In NB tissues from TH-MYCN mice, high immunoreactivity of both NPY and Y5R marked angioinvasive NB cells. Y2R was uniformly expressed in undifferentiated tumor cells, which supports its previously reported role in NB cell proliferation. Our findings validate NPY as a therapeutic target for advanced NB and implicate the NPY/Y5R axis in disease dissemination. The correlation between elevated systemic NPY and NB progression identifies serum NPY as a novel NB biomarker.


Assuntos
Neuroblastoma/metabolismo , Neuropeptídeo Y/metabolismo , Adolescente , Animais , Biomarcadores/metabolismo , Proliferação de Células , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Camundongos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Neuropeptídeo Y/genética , Receptores de Neuropeptídeo Y/genética , Receptores de Neuropeptídeo Y/metabolismo
10.
Cancer Immunol Res ; 4(10): 869-880, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27549124

RESUMO

Genetically engineered T cells expressing CD19-specific chimeric antigen receptors (CAR) have shown impressive activity against B-cell malignancies, and preliminary results suggest that T cells expressing a first-generation disialoganglioside (GD2)-specific CAR can also provide clinical benefit in patients with neuroblastoma. We sought to assess the potential of GD2-CAR therapies to treat pediatric sarcomas. We observed that 18 of 18 (100%) of osteosarcomas, 2 of 15 (13%) of rhabdomyosarcomas, and 7 of 35 (20%) of Ewing sarcomas expressed GD2. T cells engineered to express a third-generation GD2-CAR incorporating the 14g2a-scFv with the CD28, OX40, and CD3ζ signaling domains (14g2a.CD28.OX40.ζ) mediated efficient and comparable lysis of both GD2+ sarcoma and neuroblastoma cell lines in vitro However, in xenograft models, GD2-CAR T cells had no antitumor effect against GD2+ sarcoma, despite effectively controlling GD2+ neuroblastoma. We observed that pediatric sarcoma xenografts, but not neuroblastoma xenografts, induced large populations of monocytic and granulocytic murine myeloid-derived suppressor cells (MDSC) that inhibited human CAR T-cell responses in vitro Treatment of sarcoma-bearing mice with all-trans retinoic acid (ATRA) largely eradicated monocytic MDSCs and diminished the suppressive capacity of granulocytic MDSCs. Combined therapy using GD2-CAR T cells plus ATRA significantly improved antitumor efficacy against sarcoma xenografts. We conclude that retinoids provide a clinically accessible class of agents capable of diminishing the suppressive effects of MDSCs, and that co-administration of retinoids may enhance the efficacy of CAR therapies targeting solid tumors. Cancer Immunol Res; 4(10); 869-80. ©2016 AACR.


Assuntos
Imunoterapia Adotiva/métodos , Células Supressoras Mieloides/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T/metabolismo , Sarcoma/terapia , Tretinoína/farmacologia , Animais , Linhagem Celular Tumoral , Criança , Terapia Combinada , Gangliosídeos/metabolismo , Humanos , Camundongos Endogâmicos NOD , Células Supressoras Mieloides/imunologia , Neuroblastoma/imunologia , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Sarcoma/imunologia , Sarcoma/metabolismo , Sarcoma/patologia , Linfócitos T/imunologia , Linfócitos T/transplante , Resultado do Tratamento , Tretinoína/uso terapêutico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Vis Exp ; (118)2016 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-28060251

RESUMO

Hypoxia has been implicated in the metastasis of Ewing sarcoma (ES) by clinical observations and in vitro data, yet direct evidence for its pro-metastatic effect is lacking and the exact mechanisms of its action are unclear. Here, we report an animal model that allows for direct testing of the effects of tumor hypoxia on ES dissemination and investigation into the underlying pathways involved. This approach combines two well-established experimental strategies, orthotopic xenografting of ES cells and femoral artery ligation (FAL), which induces hindlimb ischemia. Human ES cells were injected into the gastrocnemius muscles of SCID/beige mice and the primary tumors were allowed to grow to a size of 250 mm3. At this stage either the tumors were excised (control group) or the animals were subjected to FAL to create tumor hypoxia, followed by tumor excision 3 days later. The efficiency of FAL was confirmed by a significant increase in binding of hypoxyprobe-1 in the tumor tissue, severe tumor necrosis and complete inhibition of primary tumor growth. Importantly, despite these direct effects of ischemia, an enhanced dissemination of tumor cells from the hypoxic tumors was observed. This experimental strategy enables comparative analysis of the metastatic properties of primary tumors of the same size, yet significantly different levels of hypoxia. It also provides a new platform to further assess the mechanistic basis for the hypoxia-induced alterations that occur during metastatic tumor progression in vivo. In addition, while this model was established using ES cells, we anticipate that this experimental strategy can be used to test the effect of hypoxia in other sarcomas, as well as tumors orthotopically implanted in sites with a well-defined blood supply route.


Assuntos
Hipóxia/patologia , Metástase Neoplásica/patologia , Sarcoma de Ewing/patologia , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos SCID , Transplante de Neoplasias
12.
Oncotarget ; 6(9): 7151-65, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25714031

RESUMO

Ewing sarcoma (ES) develops in bones or soft tissues of children and adolescents. The presence of bone metastases is one of the most adverse prognostic factors, yet the mechanisms governing their formation remain unclear. As a transcriptional target of EWS-FLI1, the fusion protein driving ES transformation, neuropeptide Y (NPY) is highly expressed and released from ES tumors. Hypoxia up-regulates NPY and activates its pro-metastatic functions. To test the impact of NPY on ES metastatic pattern, ES cell lines, SK-ES1 and TC71, with high and low peptide release, respectively, were used in an orthotopic xenograft model. ES cells were injected into gastrocnemius muscles of SCID/beige mice, the primary tumors excised, and mice monitored for the presence of metastases. SK-ES1 xenografts resulted in thoracic extra-osseous metastases (67%) and dissemination to bone (50%) and brain (25%), while TC71 tumors metastasized to the lungs (70%). Bone dissemination in SK-ES1 xenografts associated with increased NPY expression in bone metastases and its accumulation in bone invasion areas. The genetic silencing of NPY in SK-ES1 cells reduced bone degradation. Our study supports the role for NPY in ES bone invasion and provides new models for identifying pathways driving ES metastases to specific niches and testing anti-metastatic therapeutics.


Assuntos
Neoplasias Ósseas/metabolismo , Neuropeptídeo Y/química , Sarcoma de Ewing/metabolismo , Animais , Neoplasias Ósseas/patologia , Neoplasias Encefálicas/secundário , Linhagem Celular Tumoral , Movimento Celular , Meios de Cultivo Condicionados , Modelos Animais de Doenças , Feminino , Inativação Gênica , Humanos , Hipóxia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos SCID , Metástase Neoplásica , Transplante de Neoplasias , Proteínas de Fusão Oncogênica/metabolismo , Fenótipo , Proteína Proto-Oncogênica c-fli-1/metabolismo , Proteína EWS de Ligação a RNA/metabolismo , Sarcoma de Ewing/patologia
13.
Cancer ; 121(5): 697-707, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25387699

RESUMO

BACKGROUND: Ewing sarcoma (ES) is driven by fusion of the Ewing sarcoma breakpoint region 1 gene (EWSR1) with an E26 transformation-specific (ETS) transcription factor (EWS-ETS), most often the Friend leukemia integration 1 transcription factor (FLI1). Neuropeptide Y (NPY) is an EWS-FLI1 transcriptional target; it is highly expressed in ES and exerts opposing effects, ranging from ES cell death to angiogenesis and cancer stem cell propagation. The functions of NPY are regulated by dipeptidyl peptidase IV (DPPIV), a hypoxia-inducible enzyme that cleaves the peptide and activates its growth-promoting actions. The objective of this study was to determine the clinically relevant functions of NPY by identifying the associations between patients' ES phenotype and their NPY concentrations and DPP activity. METHODS: NPY concentrations and DPP activity were measured in serum samples from 223 patients with localized ES and 9 patients with metastatic ES provided by the Children's Oncology Group. RESULTS: Serum NPY levels were elevated in ES patients compared with the levels in a healthy control group and an osteosarcoma patient population, and the elevated levels were independent of EWS-ETS translocation type. Significantly higher NPY concentrations were detected in patients with ES who had tumors of pelvic and bone origin. A similar trend was observed in patients with metastatic ES. There was no effect of NPY on survival in patients with localized ES. DPP activity in sera from patients with ES did not differ significantly from that in healthy controls and patients with osteosarcoma. However, high DPP levels were associated with improved survival. CONCLUSIONS: Systemic NPY levels are elevated in patients with ES, and these high levels are associated with unfavorable disease features. DPPIV in serum samples from patients with ES is derived from nontumor sources, and its high activity is correlated with improved survival.


Assuntos
Neoplasias Ósseas/sangue , Dipeptidil Peptidase 4/sangue , Neuropeptídeo Y/sangue , Proteínas de Fusão Oncogênica/genética , Proteína Proto-Oncogênica c-fli-1/genética , Proteína EWS de Ligação a RNA/genética , Sarcoma de Ewing/sangue , Adolescente , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Linhagem Celular Tumoral , Criança , Dipeptidil Peptidase 4/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos SCID , Transplante de Neoplasias , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Osteossarcoma/sangue , Osteossarcoma/genética , RNA Mensageiro/genética , Receptores de Neuropeptídeo Y/genética , Sarcoma de Ewing/genética , Sarcoma de Ewing/mortalidade , Transplante Heterólogo
14.
Oncotarget ; 4(12): 2487-501, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24318733

RESUMO

Ewing sarcoma (ES) is an aggressive malignancy driven by an oncogenic fusion protein, EWS-FLI1. Neuropeptide Y (NPY), and two of its receptors, Y1R and Y5R are up-regulated by EWS-FLI1 and abundantly expressed in ES cells. Paradoxically, NPY acting via Y1R and Y5R stimulates ES cell death. Here, we demonstrate that these growth-inhibitory actions of NPY are counteracted by hypoxia, which converts the peptide to a growth-promoting factor. In ES cells, hypoxia induces another NPY receptor, Y2R, and increases expression of dipeptidyl peptidase IV (DPPIV), an enzyme that cleaves NPY to a shorter form, NPY3-36. This truncated peptide no longer binds to Y1R and, therefore, does not stimulate ES cell death. Instead, NPY3-36 acts as a selective Y2R/Y5R agonist. The hypoxia-induced increase in DPPIV activity is most evident in a population of ES cells with high aldehyde dehydrogenase (ALDH) activity, rich in cancer stem cells (CSCs). Consequently, NPY, acting via Y2R/Y5Rs, preferentially stimulates proliferation and migration of hypoxic ALDHhigh cells. Hypoxia also enhances the angiogenic potential of ES by inducing Y2Rs in endothelial cells and increasing the release of its ligand, NPY3-36, from ES cells. In summary, hypoxia acts as a molecular switch shifting NPY activity away from Y1R/Y5R-mediated cell death and activating the Y2R/Y5R/DPPIV/NPY3-36 axis, which stimulates ES CSCs and promotes angiogenesis. Hypoxia-driven actions of the peptide such as these may contribute to ES progression. Due to the receptor-specific and multifaceted nature of NPY actions, these findings may inform novel therapeutic approaches to ES.


Assuntos
Hipóxia Celular/fisiologia , Neuropeptídeo Y/metabolismo , Sarcoma de Ewing/metabolismo , Animais , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Dipeptidil Peptidase 4/metabolismo , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Sarcoma de Ewing/irrigação sanguínea , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia
15.
PLoS One ; 7(11): e48775, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23144964

RESUMO

Disseminated Candida albicans infection results in high morbidity and mortality despite treatment with existing antifungal drugs. Recent studies suggest that modulating the host immune response can improve survival, but specific host targets for accomplishing this goal remain to be identified. The extracellular matrix protein thrombospondin-1 is released at sites of tissue injury and modulates several immune functions, but its role in C. albicans pathogenesis has not been investigated. Here, we show that mice lacking thrombospondin-1 have an advantage in surviving disseminated candidiasis and more efficiently clear the initial colonization from kidneys despite exhibiting fewer infiltrating leukocytes. By examining local and systemic cytokine responses to C. albicans and other standard inflammatory stimuli, we identify a crucial function of phagocytes in this enhanced resistance. Subcutaneous air pouch and systemic candidiasis models demonstrated that endogenous thrombospondin-1 enhances the early innate immune response against C. albicans and promotes activation of inflammatory macrophages (inducible nitric oxide synthase⁺, IL-6(high), TNF-α(high), IL-10(low)), release of the chemokines MIP-2, JE, MIP-1α, and RANTES, and CXCR2-driven polymorphonuclear leukocytes recruitment. However, thrombospondin-1 inhibited the phagocytic capacity of inflammatory leukocytes in vivo and in vitro, resulting in increased fungal burden in the kidney and increased mortality in wild type mice. Thus, thrombospondin-1 enhances the pathogenesis of disseminated candidiasis by creating an imbalance in the host immune response that ultimately leads to reduced phagocytic function, impaired fungal clearance, and increased mortality. Conversely, inhibitors of thrombospondin-1 may be useful drugs to improve patient recovery from disseminated candidiasis.


Assuntos
Candidíase/imunologia , Neutrófilos/imunologia , Fagócitos/imunologia , Trombospondina 1/imunologia , Animais , Candida albicans/imunologia , Candidíase/mortalidade , Citocinas/imunologia , Suscetibilidade a Doenças/imunologia , Humanos , Imunidade Humoral/fisiologia , Rim/imunologia , Rim/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Imunológicos , Neutrófilos/fisiologia , Nitritos/metabolismo , Fagócitos/fisiologia , Trombospondina 1/genética , Trombospondina 1/fisiologia , Células U937
16.
J Clin Oncol ; 30(33): 4141-7, 2012 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-23071222

RESUMO

PURPOSE: Lexatumumab is an agonistic, fully human monoclonal antibody against tumor necrosis factor-related apoptosis-inducing ligand receptor 2 with preclinical evidence of activity in pediatric solid tumors. PATIENTS AND METHODS: This phase I dose-escalation study examined the safety, tolerability, pharmacokinetics, and immunogenicity of lexatumumab at doses up to, but not exceeding, the adult maximum-tolerated dose (3, 5, 8, and 10 mg/kg), administered once every 2 weeks to patients age≤21 years with recurrent or progressive solid tumors. RESULTS: Twenty-four patients received a total of 56 cycles of lexatumumab over all four planned dose levels. One patient had grade 2 pericarditis consistent with radiation recall, and one patient developed grade 3 pneumonia with hypoxia during the second cycle. Five patients experienced stable disease for three to 24 cycles. No patients experienced complete or partial response, but several showed evidence of antitumor activity, including one patient with recurrent progressive osteosarcoma who experienced resolution of clinical symptoms and positron emission tomography activity, ongoing more than 1 year off therapy. One patient with hepatoblastoma showed a dramatic biomarker response. CONCLUSION: Pediatric patients tolerate 10 mg/kg of lexatumumab administered once every 14 days, the maximum-tolerated dose identified in adults. The drug seems to mediate some clinical activity in pediatric solid tumors and may work with radiation to enhance antitumor effects.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Adolescente , Adulto , Anticorpos Monoclonais/efeitos adversos , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neoplasias/patologia , Resultado do Tratamento , Adulto Jovem
17.
OMICS ; 15(3): 105-12, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21319991

RESUMO

Limitations to biomarker discovery are not only technical or bioinformatic but conceptual as well. In our attempt to offer a solution, we are highlighting three issues that we think are limiting progress in biomarkers discovery. First, the confusion stemming from the imposition of a pathology-type immunohistochemical marker (IHCM) concept on omics data without fully understanding the characteristics and limitations of IHCMs as applied in clinical pathology. Second, the lack of serious consideration for the scope of disease heterogeneity. Third, the refusal of the biomedical community to borrow from other biological disciplines their well established methods for dealing with heterogeneity. Therefore, real progress in biomarker discovery will be attained when we recognize that an omics biomarker cannot be assigned and validated without a priori data modeling and subtyping of the disease itself to reveal the extent of its heterogeneity, and its omics' clonal aberrations (drivers) underlying its subtypes and pathways' diversity. To further support our viewpoints, we are contributing a novel a systems biology method such as parsimony phylogenetic approach for disease modeling prior to biomarker circumscription. As an analytical approach that has been successfully used for a half of a century in other biological disciplines, parsimony phylogenetics simultaneously achieves several objectives: it provides disease modeling in a hierarchical phylogenetic classification, identifies biomarkers as the shared derived expressions or mutations--synapomorphies, constructs the omics profiles of specimens based on the most parsimonious arrangement of their heterogeneous data, and permits network profiling of affected signaling pathways as the biosignature of disease classes.


Assuntos
Biomarcadores/análise , Biologia de Sistemas , Genômica , Humanos , Imuno-Histoquímica , Proteômica
18.
Cancer Res ; 68(17): 7090-9, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18757424

RESUMO

Inhibition of tumor growth by thrombospondin (TSP) 1 is generally attributed to its antiangiogenic activity, but effects on tumor immunity should also be considered. We show that overexpression of TSP1 in melanoma cells increases macrophage recruitment into xenograft tumors grown in nude or beige/nude mice. In vitro, TSP1 acutely induces expression of plasminogen activator inhibitor-1 (PAI-1) by monocytic cells, suggesting that TSP1-induced macrophage recruitment is at least partially mediated by PAI-1. Tumor-associated macrophages (TAM) can either promote or limit tumor progression. The percentage of M1-polarized macrophages expressing inducible nitric oxide synthase is increased in TSP1-expressing tumors. Furthermore, soluble TSP1 stimulates killing of breast carcinoma and melanoma cells by IFN-gamma-differentiated U937 cells in vitro via release of reactive oxygen species. TSP1 causes a significant increase in phorbol ester-mediated superoxide generation from differentiated monocytes by interaction with alpha(6)beta(1) integrin through its NH(2)-terminal region. The NH(2)-terminal domain of TSP2 also stimulates monocyte superoxide production. Extracellular calcium is required for the TSP1-induced macrophage respiratory burst. Thus, TSP1 may play an important role in antitumor immunity by enhancing recruitment and activation of M1 TAMs, which provides an additional selective pressure for loss of TSP1 and TSP2 expression during tumor progression.


Assuntos
Macrófagos/citologia , Neoplasias/patologia , Trombospondina 1/fisiologia , Animais , Diferenciação Celular , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células U937
19.
Ophthalmology ; 114(11): 2083-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17459482

RESUMO

PURPOSE: To evaluate the outcome of patients with retinoblastoma and postlaminar optic nerve invasion (PLONI). DESIGN: Retrospective interventional case series. PARTICIPANTS: Sixty-one consecutive patients included in 3 successive protocols were analyzed. METHODS: Pathologic review was done in each case. Patients were stratified into 2 risk groups: the high-risk group included those with concomitant full choroidal and/or scleral invasion and were given adjuvant chemotherapy. Those without these features were considered low risk and chemotherapy was withheld after 1994. MAIN OUTCOME MEASURES: Extraocular relapse and survival according to stratification. RESULTS: The probability of event-free survival (pEFS) was 0.91 and the probability of overall survival (pOS) was 0.94 at 5 years. Patients in the high-risk group (n = 22) had pEFS of 0.86. Three had extraocular relapse (involving the central nervous system; all died of disease). Microscopic scleral invasion was associated to extraocular relapse (P = 0.05). Lower risk patients (n = 39) had a pEFS of 0.94 and pOS of 1. Eighteen received postenucleation chemotherapy and none relapsed. Twenty-one received no adjuvant therapy and 2 had a systemic relapse but were successfully retrieved. Relapsing patients had a higher ratio of affected optic nerve (>25% of it overall length; P = 0.02). CONCLUSIONS: Patients with PLONI have an excellent outcome with current therapy. Risk stratification according to the presence of concomitant choroidal and/or scleral invasion may help in the decision of giving adjuvant therapy.


Assuntos
Neoplasias do Nervo Óptico/patologia , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Masculino , Invasividade Neoplásica , Recidiva Local de Neoplasia , Neoplasias do Nervo Óptico/tratamento farmacológico , Neoplasias do Nervo Óptico/mortalidade , Neoplasias da Retina/tratamento farmacológico , Neoplasias da Retina/mortalidade , Retinoblastoma/tratamento farmacológico , Retinoblastoma/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
20.
Buenos Aires; s.n; 1999. [60] p. ilus, tab. (83554).
Monografia em Espanhol | BINACIS | ID: bin-83554

RESUMO

Se especula que la manipulación traumática del colon portador de una neoplasia, durante la ejecución de una colectomía laparoscópica podría aumentar la exfoliación de células malignas dentro de la cavidad peritoneal, y por consiguiente ser una de las causas de los implantes cutáneos. Objetivo: desarrollar un modelo de cáncer colónico experimental con similitud al del hombre y determinar si la manipulación laparoscópica instrumental del carcinoma de colon y recto comparada con la laparotomía, aumenta la exfoliación de células malignas en la cavidad peritoneal, instrumental y trócares. Material y Métodos: se desarrolló un protocolo de cáncer colorrectal experimental con inyección subcutánea de 1-2Dimethylhydrazina a una dosis de 20 mg/Kg de peso, semanalmente y durante 20 semanas, en ratas Wistar, sexo masculino. Se operaron a la semana 21º, dividiéndolas en 2 grupos (1 y 2). Grupo 1 (n 23) sometidas a laparotomía y manipulación instrumental del colon. Grupo 2 (n 17) se efectuó neumoperitoneo con CO2 hasta una presión de 12 mmHg, laparoscopía y manipulación instrumental del colon y recto. Un tercer grupo lo constituyeron las ratas controles (n5). Se realizó citología de: líquido de lavado peritoneal pre y pos manipulación intestinal, del instrumental convencional y laparoscópico, de la aguja de Verres y de los trócares. Se efectuó el estudio del colon y recto, ganglios mesentéricos, hígado y peritoneo. Resultados: El 80 por ciento de las ratas desarrollaron adenocarcinomas de colon. No existió diferencia significativa entre la exfoliación celular de ambos grupos de animales. Conclusiones: El carcinoma colorrectal inducido por la 1-2 dimethylhydrazina tiene características muy similares al del ser humano y es un modelo válido para la investigación. La manipulación instrumental con una prolija técnica durante los procedimientos laparoscópico no aumenta la exfoliación celular. (AU)


Assuntos
Animais , Ratos , Masculino , Estudo Comparativo , /cirurgia , /patologia , Neoplasias do Colo/cirurgia , Neoplasias do Colo/patologia , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Neoplasias Experimentais/induzido quimicamente , Adenocarcinoma , Dimetilidrazinas/administração & dosagem , Lavagem Peritoneal/métodos , Lavagem Peritoneal/instrumentação , Líquido Ascítico/citologia , Laparoscopia/instrumentação , Laparotomia/instrumentação , Colectomia , Pneumoperitônio Artificial/instrumentação , Recidiva Local de Neoplasia , Sobreviventes , Ratos Wistar
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