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Neuraminidases (NEUs) also called sialidases are glycosidases which catalyze the removal of terminal sialic acid residues from glycoproteins, glycolipids, and oligosaccharides. Mammalian NEU-1 participates in regulation of cell surface receptors such as insulin receptor (IR), epithelial growth factor receptor, low-density lipoprotein receptor, and toll-like receptor 4. At the plasma membrane, NEU-1 can be associated with the elastin-binding protein and the carboxypeptidase protective protein/cathepsin A to constitute the elastin receptor complex. In this complex, NEU-1 is essential for elastogenesis, signal transduction through this receptor and for biological effects of the elastin-derived peptides on atherosclerosis, thrombosis, insulin resistance, nonalcoholic steatohepatitis, and cancers. This is why research teams are developing inhibitors targeting this sialidase. Previously, we developed interfering peptides to inhibit the dimerization and the activation of NEU-1. In this study, we investigated the effects of these peptides on IR activation in vitro and in vivo. Using cellular overexpression and endogenous expression models of NEU-1 and IR (COS-7 and HepG2 cells, respectively), we have shown that interfering peptides inhibit NEU-1 dimerization and sialidase activity which results in a reduction of IR phosphorylation. These results demonstrated that NEU-1 positively regulates IR phosphorylation and activation in our conditions. In vivo, biodistribution study showed that interfering peptides are well distributed in mice. Treatment of C57Bl/6 mice during 8 weeks with interfering peptides induces a hyperglycemic effect in our experimental conditions. Altogether, we report here that inhibition of NEU-1 sialidase activity by interfering peptides decreases IR activity in vitro and glucose homeostasis in vivo.
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Neuraminidasa , Receptor de Insulina , Neuraminidasa/metabolismo , Neuraminidasa/antagonistas & inhibidores , Animales , Receptor de Insulina/metabolismo , Humanos , Ratones , Células Hep G2 , Chlorocebus aethiops , Homeostasis/efectos de los fármacos , Péptidos/farmacología , Péptidos/química , Masculino , Glucosa/metabolismo , Ratones Endogámicos C57BL , Receptores de Superficie CelularRESUMEN
Multiple sclerosis (MS) is an autoimmune and neurodegenerative disease leading to demyelination and axonal loss. Current treatments are immunomodulatory or immunosuppressive drugs acting on the inflammatory component. However, these treatments do not adequately address the crucial aspect of neuroprotection. Recently, an association between an altered balance of adipokines and MS has been proposed as both a risk factor for developing MS and a chronic disease aggravating factor. Specifically, a decrease of apelin plasma levels in MS patients compared to controls correlates with the number of relapses and disease severity. Here we report a dramatic downregulation of apelin levels in the CNS of EAE mice which is also detected in MS patients brain samples compared to controls. Exploiting innovative design and synthesis techniques, we engineered a novel fluorinated apelin-13 peptide characterized by enhanced plasmatic stability compared to its native counterpart. With this peptide, we assessed the potential therapeutic benefits of apelin preventive supplementation in the EAE mouse model. We show that the fluorinated Apelin-13 peptide ameliorates EAE clinical score and preserves myelin content in the EAE MOG model recapitulating the progressive form of disease. These results combined with ex-vivo experiments in brain organotypic slices and in vitro studies in neurons and primary microglia and macrophages suggest that apelin has neuroprotective effects and influences the microglia/macrophages function.
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Encefalomielitis Autoinmune Experimental , Ratones Endogámicos C57BL , Esclerosis Múltiple , Fármacos Neuroprotectores , Animales , Fármacos Neuroprotectores/farmacología , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/patología , Ratones , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/patología , Modelos Animales de Enfermedad , Microglía/efectos de los fármacos , Microglía/metabolismo , Apelina/metabolismo , Apelina/farmacologíaRESUMEN
Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system associated with chronic inflammation, demyelination, and axonal damage. MS is a highly heterogeneous disease that leads to discrepancies regarding the clinical appearance, progression, and therapy response of patients. Therefore, there is a strong unmet need for clinically relevant biomarkers capable of recapitulating the features of the disease. Experimental autoimmune encephalomyelitis (EAE) is a valuable model for studying the pathophysiology of MS as it recapitulates the main hallmarks of the disease: inflammation, blood-brain barrier (BBB) disruption, gliosis, myelin damage, and repair mechanisms. In this study, we used the EAE-PLP animal model and established a molecular RNA signature for each phase of the disease (onset, peak, remission). We compared variances of expression of known biomarkers by RT-qPCR in the brain and spinal cord of sham and EAE animals monitoring each of the five hallmarks of the disease. Using magnetic cell isolation technology, we isolated microglia and oligodendrocytes of mice of each category, and we compared the RNA expression variations. We identify genes deregulated during a restricted time frame, and we provide insight into the timing and interrelationships of pathological disease processes at the organ and cell levels.
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Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Animales , Ratones , Esclerosis Múltiple/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Inflamación , Biomarcadores , ARNRESUMEN
Long QT syndrome is one of the most common hereditary channelopathies inducing fatal arrhythmias and sudden cardiac death. We identified in a sudden arrhythmic death syndrome case a C-term KCNH2 mutation (c.3457C > T; p.His1153Tyr) classified as variant of unknown significance and functional impact. Heterologous expression in HEK293 cells combined with western-blot, flow-cytometry, immunocytochemical and microscope analyses shows no modification of channel trafficking to the cell membrane. Electrophysiological studies reveal that the mutation causes a loss of HERG channel function through an alteration of channel biophysical properties that reduces the current density leading to LQT2. These results provide the first functional evidence for H1153Y-KCNH2 mutation-induced abnormal channel properties. They concur with previous biophysical and clinical presentations of a survived patient with another variant that is G1036D. Therefore, the present report importantly highlights the potential severity of variants that may have useful implications for treatment, surveillance, and follow-up of LQT2 patients.
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Arritmias Cardíacas/genética , Muerte Súbita Cardíaca , Canal de Potasio ERG1/genética , Activación del Canal Iónico , Potenciales de Acción , Arritmias Cardíacas/patología , Células Cultivadas , Canal de Potasio ERG1/química , Canal de Potasio ERG1/metabolismo , Células HEK293 , Humanos , Masculino , Mutación Missense , Dominios Proteicos , Transporte de Proteínas , Adulto JovenRESUMEN
BACKGROUND INFORMATION: Tumor stroma remodeling is a key feature of malignant tumors and can promote cancer progression. Laminins are major constituents of basement membranes that physically separate the epithelium from the underlying stroma. RESULTS: By employing mouse models expressing high and low levels of the laminin α1 chain (LMα1), we highlighted its implication in a tumor-stroma crosstalk, thus leading to increased colon tumor incidence, angiogenesis and tumor growth. The underlying mechanism involves attraction of carcinoma-associated fibroblasts by LMα1, VEGFA expression triggered by the complex integrin α2ß1-CXCR4 and binding of VEGFA to LM-111, which in turn promotes angiogenesis, tumor cell survival and proliferation. A gene signature comprising LAMA1, ITGB1, ITGA2, CXCR4 and VEGFA has negative predictive value in colon cancer. CONCLUSIONS: Together, we have identified VEGFA, CXCR4 and α2ß1 integrin downstream of LMα1 in colon cancer as of bad prognostic value for patient survival. SIGNIFICANCE: This information opens novel opportunities for diagnosis and treatment of colon cancer.
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Mechanical interaction between cells and their surrounding extracellular matrix (ECM) controls key processes such as proliferation, differentiation and motility. For many years, two-dimensional (2D) models were used to better understand the interactions between cells and their surrounding ECM. More recently, variation of the mechanical properties of tissues has been reported to play a major role in physiological and pathological scenarios such as cancer progression. The 3D architecture of the ECM finely tunes cellular behavior to perform physiologically relevant tasks. Technical limitations prevented scientists from obtaining accurate assessment of the mechanical properties of physiologically realistic matrices. There is therefore a need for combining the production of high-quality cell-derived 3D matrices (CDMs) and the characterization of their topographical and mechanical properties. Here, we describe methods that allow to accurately measure the young modulus of matrices produced by various cellular types. In the first part, we will describe and review several protocols for generating CDMs matrices from endothelial, epithelial, fibroblastic, muscle and mesenchymal stem cells. We will discuss tools allowing the characterization of the topographical details as well as of the protein content of such CDMs. In a second part, we will report the methodologies that can be used, based on atomic force microscopy, to accurately evaluate the stiffness properties of the CDMs through the quantification of their young modulus. Altogether, such methodologies allow characterizing the stiffness and topography of matrices deposited by the cells, which is key for the understanding of cellular behavior in physiological conditions.
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Matriz Extracelular/fisiología , Animales , Bovinos , Módulo de Elasticidad , Matriz Extracelular/química , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Células Madre Mesenquimatosas/fisiología , Ratones , Microscopía de Fuerza Atómica , Miocitos del Músculo Liso/fisiología , Células 3T3 NIHRESUMEN
INTRODUCTION: The quest for novel MS therapies focuses on promoting remyelination and neuroprotection, necessitating innovative drug design paradigms and robust preclinical validation methods to ensure efficient clinical translation. The complexity of new drugs action mechanisms is strengthening the need for solid biological validation attempting to address all possible pitfalls and biases precluding access to efficient and safe drugs. AREAS COVERED: In this review, the authors describe the different in vitro and in vivo models that should be used to create an integrated approach for preclinical validation of novel drugs, including the evaluation of the action mechanism. This encompasses 2D, 3D in vitro models and animal models presented in such a way to define the appropriate use in a global process of drug screening and hit validation. EXPERT OPINION: None of the current available tests allow the concomitant evaluation of anti-inflammatory, immune regulators or remyelinating agents with sufficient reliability. Consequently, the collaborative efforts of academia, industry, and regulatory agencies are essential for establishing standardized protocols, validating novel methodologies, and translating preclinical findings into clinically meaningful outcomes.
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During mouse pancreas development, the transient expression of Neurogenin3 (Neurog3) in uncommitted pancreas progenitors is required to determine endocrine destiny. However it has been reported that Neurog3-expressing cells can eventually adopt acinar or ductal fates and that Neurog3 levels were important to secure the islet destiny. It is not known whether the competence of Neurog3-induced cells to give rise to non-endocrine lineages is an intrinsic property of these progenitors or depends on pancreas developmental stage. Using temporal genetic labeling approaches we examined the dynamic of endocrine progenitor differentiation and explored the plasticity of Neurog3-induced cells throughout development. We found that Neurog3(+) progenitors develop into hormone-expressing cells in a fast process taking less then 10h. Furthermore, fate-mapping studies in heterozygote (Neurog3(CreERT/+)) and Neurog3-deficient (Neurog3(CreERT/CreERT)) embryos revealed that Neurog3-induced cells have different potential over time. At the early bud stage, failed endocrine progenitors can adopt acinar or ductal fate, whereas later in the branching pancreas they do not contribute to the acinar lineage but Neurog3-deficient cells eventually differentiate into duct cells. Thus these results provide evidence that the plasticity of Neurog3-induced cells becomes restricted during development. Furthermore these data suggest that during the secondary transition, endocrine progenitor cells arise from bipotent precursors already committed to the duct/endocrine lineages and not from domain of cells having distinct potentialities.
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Células Acinares/citología , Tipificación del Cuerpo , Sistema Endocrino/citología , Sistema Endocrino/embriología , Conductos Pancreáticos/citología , Conductos Pancreáticos/embriología , Células Madre/citología , Células Acinares/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/deficiencia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular , Linaje de la Célula , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Epitelio/embriología , Epitelio/metabolismo , Hormonas/metabolismo , Ratones , Modelos Biológicos , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/metabolismo , Conductos Pancreáticos/metabolismo , Células Madre/metabolismo , Factores de Tiempo , Torso/embriologíaRESUMEN
Interleukin 10 (IL-10) exerts anti-inflammatory and immune regulatory roles through its fixation to the IL-10 receptor (IL-10R). The two subunits (IL-10Rα and IL-10Rß) organise themselves to form a hetero-tetramer to induce the activation of the transcription factor STAT3. We analysed the activation patterns of the IL-10R, especially the contribution of the transmembrane (TM) domain of the IL-10Rα and IL-10Rß subunits, as evidence accumulates that this short domain has tremendous implications in receptor oligomerisation and activation. We also addressed whether targeting the TM domain of IL-10R with peptides mimicking the TM sequences of the subunits translates into biological consequences. The results illustrate the involvement of the TM domains from both subunits in receptor activation and feature a distinctive amino acid crucial for the interaction. The TM peptide targeting approach also appears to be suitable for modulating the activation of the receptor through its action on the dimerization capabilities of the TM domains and thereby constitutes a potential new strategy for the modulation of the inflammation in pathologic contexts.
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Regulación de la Expresión Génica , Factores de Transcripción , Receptores de Interleucina-10 , Transducción de Señal , AminoácidosRESUMEN
A better understanding of tumor development is crucial for treating cancer. Polarimetric imaging is an interesting alternative for monitoring subcutaneous tumors as it is non-invasive. In this study, a Mueller spectro-polarimeter is used to monitor tumor development on mice injected with non-pigmented breast cancer cells or with pigmented murine melanoma cells. Three stages of non-pigmented tumor development are revealed with three polarimetric parameters. These stages also appear for pigmented tumors, although less clearly. A halo of high depolarization surrounding the non-pigmented tumor in the first stage allows the outlining of the tumor. Considering polarimetric parameters, a biological interpretation is proposed.
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Radiotherapy, the most frequent treatment of oral squamous cell carcinomas (OSCC) besides surgery is employed to kill tumor cells but, radiotherapy may also promote tumor relapse where the immune-suppressive tumor microenvironment (TME) could be instrumental. We established a novel syngeneic grafting model from a carcinogen-induced tongue tumor, OSCC13, to address the impact of radiotherapy on OSCC. This model revealed similarities with human OSCC, recapitulating carcinogen-induced mutations found in smoking associated human tongue tumors, abundant tumor infiltrating leukocytes (TIL) and, spontaneous tumor cell dissemination to the local lymph nodes. Cultured OSCC13 cells and OSCC13-derived tongue tumors were sensitive to irradiation. At the chosen dose of 2 Gy mimicking treatment of human OSCC patients not all tumor cells were killed allowing to investigate effects on the TME. By investigating expression of the extracellular matrix molecule tenascin-C (TNC), an indicator of an immune suppressive TME, we observed high local TNC expression and TIL infiltration in the irradiated tumors. In a TNC knockout host the TME appeared less immune suppressive with a tendency towards more tumor regression than in WT conditions. Altogether, our novel syngeneic tongue OSCC grafting model, sharing important features with the human OSCC disease could be relevant for future anti-cancer targeting of OSCC by radiotherapy and other therapeutic approaches.
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Ganglios Linfáticos/efectos de la radiación , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Tenascina/metabolismo , Neoplasias de la Lengua/radioterapia , Animales , Línea Celular Tumoral , Femenino , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Metástasis Linfática , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Trasplante de Neoplasias , Tolerancia a Radiación , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/secundario , Tenascina/genética , Neoplasias de la Lengua/genética , Neoplasias de la Lengua/metabolismo , Neoplasias de la Lengua/patología , Trasplante Isogénico , Carga Tumoral/efectos de la radiación , Microambiente TumoralRESUMEN
Inherent immune suppression represents a major challenge in the treatment of human cancer. The extracellular matrix molecule tenascin-C promotes cancer by multiple mechanisms, yet the roles of tenascin-C in tumor immunity are incompletely understood. Using a 4NQO-induced oral squamous cell carcinoma (OSCC) model with abundant and absent tenascin-C, we demonstrated that tenascin-C enforced an immune-suppressive lymphoid stroma via CCL21/CCR7 signaling, leading to increased metastatic tumors. Through TLR4, tenascin-C increased expression of CCR7 in CD11c+ myeloid cells. By inducing CCL21 in lymphatic endothelial cells via integrin α9ß1 and binding to CCL21, tenascin-C immobilized CD11c+ cells in the stroma. Inversion of the lymph node-to-tumor CCL21 gradient, recruitment of T regulatory cells, high expression of anti-inflammatory cytokines, and matrisomal components were hallmarks of the tenascin-C-instructed lymphoid stroma. Ablation of tenascin-C or CCR7 blockade inhibited the lymphoid immune-suppressive stromal properties, reducing tumor growth, progression, and metastasis. Thus, targeting CCR7 could be relevant in human head and neck tumors, as high tenascin-C expression and an immune-suppressive stroma correlate to poor patient survival.
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Neoplasias de la Boca/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Tenascina/inmunología , Animales , Quimiocina CCL21/inmunología , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias de la Boca/patología , Receptores CCR7/inmunología , Proteínas Recombinantes/farmacología , Linfocitos T Reguladores/inmunología , Tenascina/farmacología , Microambiente Tumoral/inmunologíaRESUMEN
Components with self-assembly properties derived from plant viruses provide the opportunity to design biological nanoscaffolds for the ordered display of agents of diverse nature and with complementing functions. With the aim of designing a functionalized nanoscaffold to target cancer, the coat protein (CP) of Tobacco mosaic virus (TMV) was tested as nanocarrier for an insoluble, highly hydrophobic peptide that targets the transmembrane domain of the Neuropilin-1 (NRP1) receptor in cancer cells. The resulting construct CPL-K (CP-linker-"Kill") binds to NRP1 in cancer cells and disrupts NRP1 complex formation with PlexA1 as well as downstream Akt survival signaling. The application of CPL-K also inhibits angiogenesis and cell migration. CP was also fused to a peptide that targets the extracellular domain of NRP1 and this fusion protein (CPL-F, CP-Linker-"Find") is shown to bind to cultured cancer cells and to inhibit NRP1-dependent angiogenesis as well. CPL-K and CPL-F maintain their anti-angiogenic properties upon co-assembly to oligomers/nanoparticles together with CPL. The observations show that the CP of TMV can be employed to generate a functionalized nanoparticle with biological activity. Remarkably, fusion to CPL allowed us to solubilize the highly insoluble transmembrane NRP1 peptide and to retain its anti-angiogenic effect.
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Current treatments in multiple sclerosis (MS) are modulating the inflammatory component of the disease, but no drugs are currently available to repair lesions. Our study identifies in MS patients the overexpression of Plexin-A1, the signalling receptor of the oligodendrocyte inhibitor Semaphorin 3A. Using a novel type of peptidic antagonist, we showed the possibility to counteract the Sema3A inhibitory effect on oligodendrocyte migration and differentiation in vitro when antagonizing Plexin-A1. The use of this compound in vivo demonstrated a myelin protective effect as shown with DTI-MRI and confirmed at the histological level in the mouse cuprizone model of induced demyelination/remyelination. This effect correlated with locomotor performances fully preserved in chronically treated animals. The administration of the peptide also showed protective effects, leading to a reduced severity of demyelination in the context of experimental autoimmune encephalitis (EAE). Hence, the disruption of the inhibitory microenvironmental molecular barriers allows normal myelinating cells to exert their spontaneous remyelinating capacity. This opens unprecedented therapeutic opportunity for patients suffering a disease for which no curative options are yet available.
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Esclerosis Múltiple/fisiopatología , Proteínas del Tejido Nervioso/metabolismo , Oligodendroglía/fisiología , Receptores de Superficie Celular/metabolismo , Remielinización , Semaforina-3A/metabolismo , Transducción de Señal , Animales , Encéfalo/diagnóstico por imagen , Línea Celular , Movimiento Celular , Proliferación Celular , Modelos Animales de Enfermedad , Imagen por Resonancia Magnética , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Receptores de Superficie Celular/antagonistas & inhibidoresRESUMEN
Metastasis is a major cause of death in cancer patients. The extracellular matrix molecule tenascin-C is a known promoter of metastasis, however the underlying mechanisms are not well understood. To further analyze the impact of tenascin-C on cancer progression we generated MMTV-NeuNT mice that develop spontaneous mammary tumors, on a tenascin-C knockout background. We also developed a syngeneic orthotopic model in which tumor cells derived from a MMTV-NeuNT tumor. Tumor cells were transfected with control shRNA or with shRNA to knockdown tenascin-C expression and, were grafted into the mammary gland of immune competent, wildtype or tenascin-C knockout mice. We show that stromal-derived tenascin-C increases metastasis by reducing apoptosis and inducing the cellular plasticity of cancer cells located in pulmonary blood vessels invasions (BVI), before extravasation. We characterized BVI as organized structures of tightly packed aggregates of proliferating tumor cells with epithelial characteristics, surrounded by Fsp1+ cells, internally located platelets and, a luminal monolayer of endothelial cells. We found extracellular matrix, in particular, tenascin-C, between the stromal cells and the tumor cell cluster. In mice lacking stromal-derived tenascin-C, the organization of pulmonary BVI was significantly affected, revealing novel functions of host-derived tenascin-C in supporting the integrity of the endothelial cell coat, increasing platelet abundance, tumor cell survival, epithelial plasticity, thereby promoting overall lung metastasis. Many effects of tenascin-C observed in BVI including enhancement of cellular plasticity, survival and migration, could be explained by activation of TGF-ß signaling. Finally, in several human cancers, we also observed BVI to be surrounded by an endothelial monolayer and to express tenascin-C. Expression of tenascin-C is specific to BVI and is not observed in lymphatic vascular invasions frequent in breast cancer, which lack an endothelial lining. Given that BVI have prognostic significance for many tumor types, such as shorter cancer patient survival, increased metastasis, vessel occlusion, and organ failure, our data revealing a novel mechanism by which stromal tenascin-C promotes metastasis in human cancer, may have potential for diagnosis and therapy.
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Vasos Sanguíneos/patología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Neoplasias Mamarias Experimentales/patología , Receptor ErbB-2/genética , Tenascina/genética , Animales , Vasos Sanguíneos/metabolismo , Línea Celular Tumoral , Femenino , Técnicas de Inactivación de Genes , Humanos , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/genética , Neoplasias Mamarias Experimentales/irrigación sanguínea , Neoplasias Mamarias Experimentales/genética , Neoplasias Mamarias Experimentales/metabolismo , Ratones , Ratones Transgénicos , Ratas , Transducción de Señal , Células del Estroma , Tenascina/metabolismo , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
Muscle stem cells (MuSCs) exhibit distinct behavior during successive phases of developmental myogenesis. However, how their transition to adulthood is regulated is poorly understood. Here, we show that fetal MuSCs resist progenitor specification and exhibit altered division dynamics, intrinsic features that are progressively lost postnatally. After transplantation, fetal MuSCs expand more efficiently and contribute to muscle repair. Conversely, niche colonization efficiency increases in adulthood, indicating a balance between muscle growth and stem cell pool repopulation. Gene expression profiling identified several extracellular matrix (ECM) molecules preferentially expressed in fetal MuSCs, including tenascin-C, fibronectin, and collagen VI. Loss-of-function experiments confirmed their essential and stage-specific role in regulating MuSC function. Finally, fetal-derived paracrine factors were able to enhance adult MuSC regenerative potential. Together, these findings demonstrate that MuSCs change the way in which they remodel their microenvironment to direct stem cell behavior and support the unique demands of muscle development or repair.
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Matriz Extracelular/metabolismo , Regulación del Desarrollo de la Expresión Génica , Desarrollo de Músculos/genética , Músculo Esquelético/metabolismo , Mioblastos Esqueléticos/metabolismo , Animales , Colágeno Tipo VI/genética , Colágeno Tipo VI/metabolismo , Embrión de Mamíferos , Feto , Fibronectinas/genética , Fibronectinas/metabolismo , Genes Reporteros , Luciferasas/genética , Luciferasas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Transgénicos , Músculo Esquelético/citología , Músculo Esquelético/crecimiento & desarrollo , Mioblastos Esqueléticos/citología , Mioblastos Esqueléticos/trasplante , Transducción de Señal , Trasplante de Células Madre , Tenascina/genética , Tenascina/metabolismo , Cicatrización de Heridas/fisiologíaRESUMEN
The transmembrane domains (TMD) in membrane receptors play a key role in cell signaling. As previously shown by us a peptide targeting the TMD of neuropilin-1 (MTP-NRP1), blocks cell proliferation, cell migration and angiogenesis in vitro, and decreases glioblastoma growth in vivo. We now explored the clinical potential of MTP-NRP1 on breast cancer models and demonstrate that MTP-NRP1 blocks proliferation of several breast cancer lines including the MDA-MB-231, a triple negative human breast cancer cell line. In models with long term in vivo administration of the peptide, MTP-NRP1 not only reduced tumor volume but also decreased number and size of breast cancer metastases. Strikingly, treating mice before tumors developed protected from metastasis establishment/formation. Overall, our results report that targeting the TMD of NRP1 in breast cancer is a potent new strategy to fight against breast cancer and related metastasis.
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Neoplasias de la Mama/tratamiento farmacológico , Neuropilina-1/química , Péptidos/farmacología , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Células HEK293 , Humanos , Estimación de Kaplan-Meier , Células MCF-7 , Ratones , Metástasis de la NeoplasiaRESUMEN
Besides digesting nutrients, the gut protects the host against invasion by pathogens. Enterocytes may be subjected to damage by both microbial and host defensive responses, causing their death. Here, we report a rapid epithelial response that alleviates infection stress and protects the enterocytes from the action of microbial virulence factors. Intestinal epithelia exposed to hemolysin, a pore-forming toxin secreted by Serratia marcescens, undergo an evolutionarily conserved process of thinning followed by the recovery of their initial thickness within a few hours. In response to hemolysin attack, Drosophila melanogaster enterocytes extrude most of their apical cytoplasm, including damaged organelles such as mitochondria, yet do not lyse. We identify two secreted peptides, the expression of which requires CyclinJ, that mediate the recovery phase in which enterocytes regain their original shape and volume. Epithelial thinning and recovery constitute a fast and efficient response to intestinal infections, with pore-forming toxins acting as alarm signals.
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Toxinas Bacterianas/toxicidad , Sistema Digestivo/efectos de los fármacos , Enterocitos/efectos de los fármacos , Enterocitos/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Animales , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Citoplasma/efectos de los fármacos , Sistema Digestivo/inmunología , Sistema Digestivo/microbiología , Sistema Digestivo/patología , Modelos Animales de Enfermedad , Drosophila melanogaster , Enterocitos/patología , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidad , Enfermedades Intestinales/microbiología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Microvellosidades/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Infecciones por Serratia , Serratia marcescens/metabolismo , Serratia marcescens/patogenicidad , Sobrevida , Varroidae , Factores de VirulenciaRESUMEN
The neuropilin-plexin receptor complex regulates tumor cell migration and proliferation and thus is an interesting therapeutic target. High expression of neuropilin-1 is indeed associated with a bad prognosis in glioma patients. Q-RTPCR and tissue-array analyses showed here that Plexin-A1 is highly expressed in glioblastoma and that the highest level of expression correlates with the worse survival of patients. We next identified a developmental and tumor-associated pro-angiogenic role of Plexin-A1. Hence, by using molecular simulations and a two-hybrid like assay in parallel with biochemical and cellular assays we developed a specific Plexin-A1 peptidic antagonist disrupting transmembrane domain-mediated oligomerization of the receptor and subsequent signaling and functional activity. We found that this peptide exhibits anti-tumor activity in vivo on different human glioblastoma models including glioma cancer stem cells. Thus, screening Plexin-A1 expression and targeting Plexin-A1 in glioblastoma patients exhibit diagnostic and therapeutic value.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias Encefálicas/patología , Glioma/patología , Neovascularización Patológica/prevención & control , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Péptidos/farmacología , Receptores de Superficie Celular/antagonistas & inhibidores , Animales , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Embrión de Pollo , Membrana Corioalantoides/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patología , Glioma/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Proteínas del Tejido Nervioso/metabolismo , Dominios Proteicos , Receptores de Superficie Celular/metabolismo , Análisis de Matrices Tisulares , Pez CebraRESUMEN
Despite an increasing knowledge about the causes of cancer, this disease is difficult to cure and still causes far too high a death rate. Based on advances in our understanding of disease pathogenesis, novel treatment concepts, including targeting the tumor microenvironment, have been developed and are being combined with established treatment regimens such as surgical removal and radiotherapy. Yet it is obvious that we need additional strategies to prevent tumor relapse and metastasis. Given its exceptional high expression in most cancers with low abundance in normal tissues, tenascin-C appears an ideal candidate for tumor treatment. Here, we will summarize the current applications of targeting tenascin-C as a treatment for different tumors, and highlight the potential of this therapeutic approach.