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1.
Nat Commun ; 12(1): 5006, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408135

RESUMO

Obesity is a strong risk factor for cancer progression, posing obesity-related cancer as one of the leading causes of death. Nevertheless, the molecular mechanisms that endow cancer cells with metastatic properties in patients affected by obesity remain unexplored.Here, we show that IL-6 and HGF, secreted by tumor neighboring visceral adipose stromal cells (V-ASCs), expand the metastatic colorectal (CR) cancer cell compartment (CD44v6 + ), which in turn secretes neurotrophins such as NGF and NT-3, and recruits adipose stem cells within tumor mass. Visceral adipose-derived factors promote vasculogenesis and the onset of metastatic dissemination by activation of STAT3, which inhibits miR-200a and enhances ZEB2 expression, effectively reprogramming CRC cells into a highly metastatic phenotype. Notably, obesity-associated tumor microenvironment provokes a transition in the transcriptomic expression profile of cells derived from the epithelial consensus molecular subtype (CMS2) CRC patients towards a mesenchymal subtype (CMS4). STAT3 pathway inhibition reduces ZEB2 expression and abrogates the metastatic growth sustained by adipose-released proteins. Together, our data suggest that targeting adipose factors in colorectal cancer patients with obesity may represent a therapeutic strategy for preventing metastatic disease.


Assuntos
Tecido Adiposo/citologia , Reprogramação Celular , Neoplasias do Colo/fisiopatologia , Células-Tronco Neoplásicas/citologia , Nicho de Células-Tronco , Tecido Adiposo/metabolismo , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos SCID , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica , Células-Tronco/citologia , Células-Tronco/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo
2.
Cell Death Dis ; 12(4): 316, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767160

RESUMO

The prognosis of locally advanced colorectal cancer (CRC) is currently unsatisfactory. This is mainly due to drug resistance, recurrence, and subsequent metastatic dissemination, which are sustained by the cancer stem cell (CSC) population. The main driver of the CSC gene expression program is Wnt signaling, and previous reports indicate that Wnt3a can activate p38 MAPK. Besides, p38 was shown to feed into the canonical Wnt/ß-catenin pathway. Here we show that patient-derived locally advanced CRC stem cells (CRC-SCs) are characterized by increased expression of p38α and are "addicted" to its kinase activity. Of note, we found that stage III CRC patients with high p38α levels display reduced disease-free and progression-free survival. Extensive molecular analysis in patient-derived CRC-SC tumorspheres and APCMin/+ mice intestinal organoids revealed that p38α acts as a ß-catenin chromatin-associated kinase required for the regulation of a signaling platform involved in tumor proliferation, metastatic dissemination, and chemoresistance in these CRC model systems. In particular, the p38α kinase inhibitor ralimetinib, which has already entered clinical trials, promoted sensitization of patient-derived CRC-SCs to chemotherapeutic agents commonly used for CRC treatment and showed a synthetic lethality effect when used in combination with the MEK1 inhibitor trametinib. Taken together, these results suggest that p38α may be targeted in CSCs to devise new personalized CRC treatment strategies.

4.
Gut ; 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436496

RESUMO

OBJECTIVE: Cancer stem cells are responsible for tumour spreading and relapse. Human epidermal growth factor receptor 2 (HER2) expression is a negative prognostic factor in colorectal cancer (CRC) and a potential target in tumours carrying the gene amplification. Our aim was to define the expression of HER2 in colorectal cancer stem cells (CR-CSCs) and its possible role as therapeutic target in CRC resistant to anti- epidermal growth factor receptor (EGFR) therapy. DESIGN: A collection of primary sphere cell cultures obtained from 60 CRC specimens was used to generate CR-CSC mouse avatars to preclinically validate therapeutic options. We also made use of the ChIP-seq analysis for transcriptional evaluation of HER2 activation and global RNA-seq to identify the mechanisms underlying therapy resistance. RESULTS: Here we show that in CD44v6-positive CR-CSCs, high HER2 expression levels are associated with an activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway, which promotes the acetylation at the regulatory elements of the Erbb2 gene. HER2 targeting in combination with phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase kinase (MEK) inhibitors induces CR-CSC death and regression of tumour xenografts, including those carrying Kras and Pik3ca mutation. Requirement for the triple targeting is due to the presence of cancer-associated fibroblasts, which release cytokines able to confer CR-CSC resistance to PI3K/AKT inhibitors. In contrast, targeting of PI3K/AKT as monotherapy is sufficient to kill liver-disseminating CR-CSCs in a model of adjuvant therapy. CONCLUSIONS: While PI3K targeting kills liver-colonising CR-CSCs, the concomitant inhibition of PI3K, HER2 and MEK is required to induce regression of tumours resistant to anti-EGFR therapies. These data may provide a rationale for designing clinical trials in the adjuvant and metastatic setting.

5.
Oncogene ; 39(5): 987-1003, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31591478

RESUMO

Despite intense research and clinical efforts, patients affected by advanced colorectal cancer (CRC) have still a poor prognosis. The discovery of colorectal (CR) cancer stem cell (CSC) as the cell compartment responsible for tumor initiation and propagation may provide new opportunities for the development of new therapeutic strategies. Given the reduced sensitivity of CR-CSCs to chemotherapy and the ability of bone morphogenetic proteins (BMP) to promote colonic stem cell differentiation, we aimed to investigate whether an enhanced variant of BMP7 (BMP7v) could sensitize to chemotherapy-resistant CRC cells and tumors. Thirty-five primary human cultures enriched in CR-CSCs, including four from chemoresistant metastatic lesions, were used for in vitro studies and to generate CR-CSC-based mouse avatars to evaluate tumor growth and progression upon treatment with BMP7v alone or in combination with standard therapy or PI3K inhibitors. BMP7v treatment promotes CR-CSC differentiation and recapitulates the cell differentiation-related gene expression profile by suppressing Wnt pathway activity and reducing mesenchymal traits and survival of CR-CSCs. Moreover, in CR-CSC-based mouse avatars, BMP7v exerts an antiangiogenic effect and sensitizes tumor cells to standard chemotherapy regardless of the mutational, MSI, and CMS profiles. Of note, tumor harboring PIK3CA mutations were affected to a lower extent by the combination of BMP7v and chemotherapy. However, the addition of a PI3K inhibitor to the BMP7v-based combination potentiates PIK3CA-mutant tumor drug response and reduces the metastatic lesion size. These data suggest that BMP7v treatment may represent a useful antiangiogenic and prodifferentiation agent, which renders CSCs sensitive to both standard and targeted therapies.


Assuntos
Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/farmacologia , Neoplasias Colorretais/patologia , Mutação , Animais , Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Humanos , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Epigenomics ; 11(6): 587-604, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31066579

RESUMO

Aim: To investigate the genome-wide methylation of genetically characterized colorectal cancer stem cell (CR-CSC) lines. Materials & methods: Eight CR-CSC lines were isolated from primary colorectal cancer (CRC) tissues, cultured and characterized for aneuploidy, mutational status of CRC-related genes and microsatellite instability (MSI). Genome-wide DNA methylation was assessed by MethylationEPIC microarray. Results: We describe a distinctive methylation pattern that is maintained following in vivo passages in immune-compromised mice. We identified an epigenetic CR-CSC signature associated with MSI. We noticed that the preponderance of the differentially methylated positions do not reside at CpG islands, but spread to shelf and open sea regions. Conclusion: Given that CRCs with MSI-high status have a lower metastatic potential, the identification of a MSI-related methylation signature could provide new insights and possible targets into metastatic CRC.


Assuntos
Neoplasias do Colo/genética , Metilação de DNA , Instabilidade de Microssatélites , Células-Tronco Neoplásicas/patologia , Animais , Neoplasias do Colo/patologia , Ilhas de CpG/genética , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética , Xenoenxertos , Humanos , Camundongos
7.
Stem Cell Res Ther ; 8(1): 236, 2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-29058626

RESUMO

BACKGROUND: The use of stem cells, including mesenchymal stem cells (MSCs), for regenerative medicine is gaining interest for the clinical benefits so far obtained in patients. This study investigates the use of adipose autologous tissue in combination with platelet-rich plasma (PRP) to improve the clinical outcome of patients affected by systemic sclerosis (SSc). METHODS: Adipose-derived mesenchymal stem cells (AD-MSCs) and PRPs were purified from healthy donors and SSc patients. The multilineage differentiation potential of AD-MSCs and their genotypic-phenotypic features were investigated. A cytokine production profile was evaluated on AD-MSCs and PRPs from both healthy subjects and SSc patients. The adipose tissue-derived cell fraction, the so-called stromal vascular fraction (SVF), was coinjected with PRP in the perioral area of SSc patients. RESULTS: Histopathological and phenotypical analysis of adipose tissue from SSc patients revealed a disorganization of its distinct architecture coupled with an altered cell composition. Although AD-MSCs derived from SSc patients showed high multipotency, they failed to sustain a terminally differentiated progeny. Furthermore, SVFs derived from SSc patients differed from healthy donors in their MSC-like traits coupled with an aberrant cytokine production profile. Finally, the administration of PRP in combination with autologous SVF improved buccal's rhyme, skin elasticity and vascularization for all of the SSc patients enrolled in this study. CONCLUSIONS: This innovative regenerative therapy could be exploited for the treatment of chronic connective tissue diseases, including SSc.


Assuntos
Tecido Adiposo/citologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Plasma Rico em Plaquetas/fisiologia , Medicina Regenerativa/métodos , Escleroderma Sistêmico/terapia , Tecido Adiposo/imunologia , Adulto , Idoso de 80 Anos ou mais , Antígenos CD/genética , Antígenos CD/imunologia , Diferenciação Celular , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos/métodos , Citocinas/genética , Citocinas/imunologia , Feminino , Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/imunologia , Pessoa de Meia-Idade , Neovascularização Fisiológica , Cultura Primária de Células , Escleroderma Sistêmico/imunologia , Escleroderma Sistêmico/patologia , Pele/patologia
8.
Proc Natl Acad Sci U S A ; 106(34): 14646-51, 2009 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-19667192

RESUMO

Neutrophil migration into injured tissues is invariably accompanied by pain. Bv8/prokineticin 2 (PK2), a chemokine characterized by a unique structural motif comprising five disulfide bonds, is highly expressed in inflamed tissues associated to infiltrating cells. Here, we demonstrate the fundamental role of granulocyte-derived PK2 (GrPK2) in initiating inflammatory pain and driving peripheral sensitization. In animal models of complete Freund's adjuvant-induced paw inflammation the development and duration of pain temporally correlated with the expression levels of PK2 in the inflamed sites. Such an increase in PK2 mRNA depends mainly on a marked up-regulation of PK2 gene transcription in granulocytes. A substantially lower up-regulation was also detected in macrophages. From a pool of peritoneal granulocytes, elicited in rats by oyster glycogen, we purified the GrPK2 protein, which displayed high affinity for the prokineticin receptors (PKRs) and, when injected into the rat paw, induced hypersensitivity to noxious stimuli as the amphibian prokineticin Bv8 did. Mice lacking PKR1 or PKR2 developed significantly less inflammation-induced hyperalgesia in comparison with WT mice, confirming the involvement of both PKRs in inflammatory pain. The inflammation-induced up-regulation of PK2 was significantly less in pkr1 null mice than in WT and pkr2 null mice, demonstrating a role of PKR1 in setting PK2 levels during inflammation. Pretreatment with a nonpeptide PKR antagonist, which preferentially binds PKR1, dose-dependently reduced and eventually abolished both prokineticin-induced hypernociception and inflammatory hyperalgesia. Inhibiting PK2 formation or antagonizing PKRs may represent another therapeutic approach for controlling inflammatory pain.


Assuntos
Hormônios Gastrointestinais/genética , Granulócitos/metabolismo , Inflamação/fisiopatologia , Neuropeptídeos/genética , Dor/fisiopatologia , Animais , Células CHO , Cricetinae , Cricetulus , Adjuvante de Freund , Hiperalgesia/fisiopatologia , Hiperalgesia/prevenção & controle , Hibridização In Situ , Inflamação/induzido quimicamente , Inflamação/genética , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo , Dor/prevenção & controle , Medição da Dor , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triazinas/farmacologia , Regulação para Cima/genética
9.
Int Rev Neurobiol ; 85: 145-57, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19607967

RESUMO

Bv8 is a small protein secreted by frog skin. Mammalian homologues of Bv8, the prokineticins PK1 and PK2, and their G-protein coupled receptors prokineticin receptor 1 (PKR1) and prokineticin receptor 2 (PKR2) have been identified and linked to several biological effects as gut motility, neurogenesis, angiogenesis, circadian rhythms, hematopoiesis, and nociception. Emerging evidences indicated that prokineticins are also associated with pathologies of the reproductive and nervous system, myocardial infarction, and tumorigenesis. Bv8 elicits a dose-dependent reduction in nociceptive threshold to thermal, mechanical, and chemical stimuli. The prokineticin receptors are present in a fraction of C- and Adelta-fiber neurons also expressing the vanilloid receptors, TRPV1 and TRPA1. Mice lacking PKR genes exhibit impaired Bv8-induced hyperalgesia, develop deficient responses to noxious heat, capsaicin, and protons and show reduced thermal and mechanical hypersensitivity to paw inflammation, indicating a requirement for PKR signaling in activation and sensitization of primary afferent fibers. Bv8/PK2 is highly expressed by neutrophils and other inflammatory cells and must be considered as new pronociceptive mediators in inflamed tissues. Bv8-like hyperalgesic activity was demonstrated in extracts of rat inflammatory granulocytes. Bv8 stimulates macrophage and T lymphocyte to differentiate towards an inflammatory and Th1 profile indicating that Bv8/PK2 plays a role in immunoinflammatory responses. Blockade of PKRs may represent a novel therapeutic strategy in acute and inflammatory pain conditions.


Assuntos
Proteínas de Anfíbios/farmacologia , Neuropeptídeos/farmacologia , Dor/fisiopatologia , Receptores Acoplados a Proteínas G/fisiologia , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Hormônios Gastrointestinais/genética , Hormônios Gastrointestinais/fisiologia , Humanos , Inflamação/metabolismo , Dados de Sequência Molecular , Neuropeptídeos/genética , Neuropeptídeos/fisiologia , Receptores Acoplados a Proteínas G/genética , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/genética , Fator de Crescimento do Endotélio Vascular Derivado de Glândula Endócrina/fisiologia
10.
J Med Chem ; 51(23): 7635-9, 2008 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-19006379

RESUMO

On the basis of a Janssen's patent, we approached a new synthesis of some 1,3,5-triazin-4,6-diones as potential non peptidic prokineticin receptor antagonists, containing the following substitutions: (N(1) and N(5) link a 4-methoxybenzyl and a 4-ethylbenzyl, respectively; C(2) can link an amino-ethyl-guanidine (reference compound 1) or an ethylendiamine (2) or an amino-ethyl-amino-2-imidazoline (3). New compounds were assessed for PKR1 and PKR2 affinity. Antagonist properties were evaluated as inhibition of 1 nM Bv8-induced intracellular Ca2+ mobilization.


Assuntos
Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Peptídeos/antagonistas & inibidores , Triazinas/farmacologia , Sítios de Ligação/efeitos dos fármacos , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Hormônios Gastrointestinais/química , Humanos , Ligantes , Estrutura Molecular , Neuropeptídeos/química , Estereoisomerismo , Relação Estrutura-Atividade , Triazinas/síntese química , Triazinas/química
11.
Prog Brain Res ; 148: 259-82, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15661196

RESUMO

Previous studies often considered the basilar pontine nuclei (BPN) and the nucleus reticularis tegmenti pontis (NRTP) as relays of a single cerebro-(ponto)-cerebellar pathway. Conversely, the different cortical afferences to the BPN and the NRTP, as well as the anatomical and functional features of the cerebellopetal projections from these pontine nuclei, support the different, and for some aspect, complementary arrangement of the cerebrocerebellar pathways relayed by the BPN or NRTP. Both the BPN and the NRTP are innervated from the cerebral cortex, but with regional prevalence. The NRTP is principally innervated from motor or sensori-motor areas while the BPN are principally innervated from sensory, mainly teloceptive, and associative area. Projections from sensory-motor areas were also traced to the BPN. The BPN and NRTP project to all parts of the cerebellar cortex with a similar pattern. In fact, from single areas of them projections were traced to set of sagittal stripes of the cerebellar cortex. In variance to such analogies, the projections to the cerebellar nuclei differed between those traced from the NRTP and from BPN. In fact, BPN and NRTP have private terminal areas in the cerebellar nuclei with relatively little overlaps. The BPN innervated the lateroventral part of the nucleus lateralis and the caudoventral aspect of the nucleus interpositalis posterioris. The NRTP principally innervated the mediodorsal part of the nucleus lateralis, the nucleus interpositalis anterioris, the nucleus medialis. Since the single cerebellar nuclei have their specific targets in the extracerebellar brain areas, it follows that the BPN and the NRTP, passing through their cerebellar nuclei relays, are devoted to control different brain areas and thus likely to play different functional roles. From single pontine regions (of both BPN and NRTP) projections were traced to the cerebellar cortex and to the cerebellar nuclei. In some cases these projections reached areas which are likely anatomically connected (by Purkinje axons). This pattern of the pontine projections was termed as coupled projection. In some other cases, the projections reached areas of the cerebellar cortex but not the nuclear regions innervated by them. We termed this as uncoupled projection. The existence of both coupled and uncoupled projections, open new vistas on the functional architecture of the pontocerebellar pathway. More in detail, this study showed the different quantitative and topographic distribution of the coupled and uncoupled projections visualized in the cerebellar projections from BPN and NRTP. All these evidences strongly support the anatomical and the functional differences that characterise the cerebrocerebellar pathways relayed by the BPN and the NRTP.


Assuntos
Cerebelo/citologia , Cerebelo/fisiologia , Ponte/citologia , Ponte/fisiologia , Animais , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Vias Neurais , Ratos
12.
Gene ; 328: 121-6, 2004 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-15019991

RESUMO

In this study, a new gap junction (GJ) connexin (Cx) gene was isolated from the neural tube of chicken (c) embryos (HH21) and cloned by degenerate reverse transcription-polymerase chain reaction (RT-PCR). The open reading frame of the gene encodes for a protein of 343 amino acid residues with strong similarity to highly conserved connexin sequences. On the basis of the predicted molecular mass of 39144 kDa, we denominated it as cCx39. Sequence analysis allocated the cCx39 to the alpha-group of connexin gene family. The mRNA expression of cCx39 was detected by RT-PCR and Northern blot in several tissues of chicken, including different parts of central nervous system, heart, liver, kidney, aorta and ovary. In situ hybridisation analysis of chicken brain showed strong expression in neurons of granular layers of cerebellum, optic tectum and ectostriatum. The in situ hybridisation of extracererebral tissues revealed strong expression of cCx39 in the atrium of the heart, the external layer of the aorta and endothelium of biliary vessels; moderate expression was found in the endothelium of the aorta.


Assuntos
Proteínas Aviárias/genética , Conexinas/genética , Regulação da Expressão Gênica no Desenvolvimento , Sistema Nervoso/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Embrião de Galinha , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Feminino , Hibridização In Situ , Dados de Sequência Molecular , Sistema Nervoso/embriologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
13.
Brain Res Dev Brain Res ; 148(2): 179-83, 2004 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-14766195

RESUMO

The present study reports the expression pattern of connexin39 (cCx39) in chick embryos at different stages of central nervous system development. We examined the expression between HH17 and HH40 developmental stages of chicken embryos by in situ hybridization (ISH) technique. Connexin39 was first expressed at HH17. It stained neuroepithelial cells in the optic (OV) and telencephalic (TEL) vesicles, plus in the superficial mesenchyme of the two rostral branchial arches (maxilar and mandibular). These cells probably originated from the neural crest. This expression pattern changed drastically between stages HH17 and HH23, while it showed relatively little modifications from HH23 to HH29. At these times, connexin39 was expressed in three regions: the telencephalic vesicle, the diencephalon and the isthmus. At later stages, HH35 and HH40, connexin39 was mainly expressed in the ventricular epithelium and three cell layers of the stratum griseum and fibrosum superficialis (SGFS) in the optic tectum, as well as in granular and nuclear cells in the cerebellum. In conclusion, the expression pattern of connexin39 in embryonic nervous system is dynamic. This pattern is different from, and in some aspects complementary to, those showed by other connexins during brain development.


Assuntos
Conexinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Sistema Nervoso/metabolismo , Animais , Padronização Corporal/genética , Embrião de Galinha , Conexinas/genética , Células Epiteliais/metabolismo , Hibridização In Situ/métodos , Sistema Nervoso/embriologia , Colículos Superiores/metabolismo
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