RESUMEN
Colorectal cancer (CRC) is the third most common cancer worldwide. Even if 5-fluorouracil (5-FU) is used as the first-line chemotherapeutic drug, responsiveness is only 20-30%. Acquired resistance to 5-FU contributes to both poor patient prognosis and relapse, emphasizing the need to identify biomarkers. Sortilin, a vacuolar protein sorting 10 protein (Vps10p), implicated in protein trafficking, is over expressed in CRC cell lines cultured 72 hours in presence of 5-FU. This overexpression was also observed in 5-FU-resistant cells derived from these cell lines as well as in CRC primary cultures (or patients derived cell lines). A significantly higher expression of sortilin was observed in vivo, in 5-FU-treated tumours engrafted in Nude mice, as compared with non-treated tumour. A study of transcriptional regulation allowed identifying a decrease in ATF3 expression, as an explanation of sortilin overexpression following 5-FU treatment. In silico analysis revealed SORT1 expression correlation with poor prognosis. Moreover, sortilin expression was found to be positively correlated with CRC tumour grades. Collectively, our findings identify sortilin as a potential biomarker of 5-FU resistance associated with poor clinical outcomes and aggressiveness in CRC. As a new prognostic factor, sortilin expression could be used to fight against CRC.
Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos , Fluorouracilo/uso terapéutico , Proteínas Adaptadoras del Transporte Vesicular/genética , Anciano , Anciano de 80 o más Años , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones Desnudos , Clasificación del Tumor , Pronóstico , Transporte de Proteínas/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Resultado del Tratamiento , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Small extracellular vesicles (sEVs) including exosomes, carrying the CD20, could be involved in immunotherapy resistance in diffuse large B cell lymphoma (DLBCL). We have reported endogenous brain-derived neurotrophic factor/TrkB (tropomyosin-related kinase B) survival axis in DLBCL. Here, we performed a comparative study of sEV production by germinal centre B cell (GCB) and activated B cell (ABC)-DLBCL cell lines, and analysed TrkB activation on this process. METHODS: GCB (SUDHL4 and SUDHL6) and ABC (OCI-LY3, OCI-LY10 and U2932) cell lines were used. sEVs were characterised using nanoparticle tracking analysis technology and western blot. CD20 content was also analysed by enzyme-linked immunoassay, and complement-dependent cytotoxicity of rituximab was investigated. 7,8-Dihydroxyflavone (7,8-DHF) was used as a TrkB agonist. In vivo role of sEVs was evaluated in a xenograft model. RESULTS: sEVs production varied significantly between DLBCL cells, independently of subtype. CD20 level was consistent with that of parental cells. Higher CD20 expression was found in sEVs after TrkB activation, with a trend in increasing their concentration. sEVs determined in vitro and in vivo protection from rituximab, which seemed CD20 level-dependent; the protection was enhanced when sEVs were produced by 7,8-DHF-treated cells. CONCLUSIONS: DLBCL-derived sEVs have the differential capacity to interfere with immunotherapy, which could be enhanced by growth factors like neurotrophins. Evaluating the sEV CD20 level could be useful for disease monitoring.
Asunto(s)
Antígenos CD20/metabolismo , Vesículas Extracelulares/metabolismo , Linfoma de Células B Grandes Difuso/genética , Glicoproteínas de Membrana/metabolismo , Receptor trkB/metabolismo , Animales , Línea Celular Tumoral , Xenoinjertos , Humanos , Ratones , Ratones SCIDRESUMEN
BACKGROUND: Giant cell arteritis (GCA) is a systemic vasculitis of large and medium vessels characterized by an inflammatory arterial infiltrate. GCA begins in the adventitia and leads to vascular remodeling by promoting proliferation of myofibroblasts in the intima. The morphology of the fibroblasts in the adventitia in GCA is unclear. Access to temporal artery biopsies allows morphological studies and evaluation of the microenvironment of the arterial wall. We evaluated the distribution of vascular fibroblasts and of markers of their activation in GCA. METHODS: Formalin-fixed paraffin-embedded tissue sections from 29 patients with GCA and 36 controls were examined. Immunohistochemistry was performed for CD90, vimentin, desmin, alpha-smooth muscle actin (ASMA), prolyl-4-hydroxylase (P4H), and myosin to evaluate the distribution of fibroblasts within the intima, media, and adventitia. RESULTS: Temporal arteries from patients with GCA showed increased levels of CD90, vimentin, and ASMA in the adventitia and intima compared to the controls. Desmin was expressed only in the media in both groups. P4H was expressed similarly in the adventitia and intima in the two groups. Adventitial and intimal CD90+ cells co-expressed P4H, ASMA, and myosin at a high level in GCA. CONCLUSION: The results suggest a role for adventitial fibroblasts in GCA. Inhibiting the differentiation of adventitial fibroblasts to myofibroblasts has therapeutic potential for GCA.
Asunto(s)
Fibroblastos/metabolismo , Arteritis de Células Gigantes/patología , Inmunohistoquímica/métodos , Arterias Temporales/patología , Actinas/metabolismo , Adventicia/metabolismo , Anciano , Biomarcadores/metabolismo , Biopsia , Estudios de Casos y Controles , Proliferación Celular , Desmina/metabolismo , Femenino , Arteritis de Células Gigantes/diagnóstico , Arteritis de Células Gigantes/fisiopatología , Humanos , Masculino , Arterias Temporales/metabolismo , Antígenos Thy-1/metabolismo , Microambiente Tumoral , Túnica Íntima/metabolismo , Remodelación Vascular , Vimentina/metabolismoRESUMEN
Glioblastoma multiform (GBM), the most common and aggressive primary brain tumor, is characterized by a high degree of hypoxia and resistance to therapy because of its adaptation capacities, including autophagy and growth factors signaling. In this study, we show an efficient hypoxia-induced survival autophagy in four different GBM cell lines (U87MG, M059K, M059J and LN-18) and an activation of a particular neurotrophin signaling pathway. Indeed, the enhancement of both TrkC and NT-3 was followed by downstream p38MAPK phosphorylation, suggesting the occurrence of a survival autocrine loop. Autophagy inhibition increased the hypoxia-induced expression of TrkC and its phosphorylated form as well as the phosphorylation of p38, suggesting a complementary effect of the two processes, leading to cell survival. Alone, autophagy inhibition reduced cellular growth without inducing cell death. However, the double inhibition of autophagy and TrkC signaling was necessary to bring cells to death as shown by PARP cleavage, particularly important in hypoxia. Moreover, a very high expression of TrkC and NT-3 was found in tumor sections from GBM patients, highlighting the importance of neurotrophic signaling in GBM tumor cell survival. These data suggest that a combined treatment targeting these two pathways could be considered in order to induce the death of GBM cells.
Asunto(s)
Autofagia , Neoplasias Encefálicas/patología , Glioblastoma/patología , Factores de Crecimiento Nervioso/metabolismo , Receptor trkC/metabolismo , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Glioblastoma/metabolismo , Humanos , Hipoxia , Neurotrofina 3 , Fosforilación , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Colorectal cancer (CRC) is the most common digestive cancer in the Western world. Despite effective therapies, resistance and/or recurrence frequently occur. The present study investigated the impact of two survival pathways-neurotrophic factors (TrkB/BDNF) and autophagy-on cell fate and tumour evolution. In vitro studies were performed on two CRC cell lines, SW480 (primary tumour) and SW620 (lymph node invasion), which were also used for subcutaneous xenografts on a nude mouse model. In addition, the presence of neurotrophic factors (NTs) and autophagy markers were assessed in tissue samples representative of different stages. On the basis of our previous study (which demonstrated that TrkB overexpression is associated with prosurvival signaling in CRC cells), we pharmacologically inhibited NTs pathways with K252a. As expected, an inactivation of the PI3K/AKT pathway was observed and CRC cells initiated autophagy. Conversely, blocking the autophagic flux with chloroquine or with ATG5-siRNA overactivated TrkB/BDNF signaling. In vitro, dual inhibition improved the effectiveness of single treatment by significantly reducing metabolic activity and enhancing apoptotic cell death. These findings were accentuated in vivo, in which dual inhibition induced a spectacular reduction in tumour volume following long-term treatment (21 days for K252a and 12 days for CQ). Finally, significant amounts of phospho-TrkB and LC3II were found in the patients' tissues, highlighting their relevance in CRC tumour biology. Taken together, our results show that targeting NTs and autophagy pathways potentially constitutes a new therapeutic approach for CRC.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Autofagia/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/antagonistas & inhibidores , Neoplasias Colorrectales/tratamiento farmacológico , Receptor trkB/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto , Anciano , Anciano de 80 o más Años , Animales , Proteína 5 Relacionada con la Autofagia/genética , Proteína 5 Relacionada con la Autofagia/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Carbazoles/administración & dosificación , Línea Celular Tumoral , Cloroquina/administración & dosificación , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Inhibidores Enzimáticos/administración & dosificación , Femenino , Humanos , Alcaloides Indólicos/administración & dosificación , Masculino , Ratones Endogámicos , Ratones Desnudos , Interferencia de ARN , Receptor trkB/metabolismo , Estudios Retrospectivos , Carga Tumoral/efectos de los fármacosRESUMEN
Glioblastoma is the most lethal brain tumour with a poor prognosis. Cancer stem cells (CSC) were proposed to be the most aggressive cells allowing brain tumour recurrence and aggressiveness. Current challenge is to determine CSC signature to characterize these cells and to develop new therapeutics. In a previous work, we achieved a screening of glycosylation-related genes to characterize specific genes involved in CSC maintenance. Three genes named CHI3L1, KLRC3 and PRUNE2 were found overexpressed in glioblastoma undifferentiated cells (related to CSC) compared to the differentiated ones. The comparison of their roles suggest that KLRC3 gene coding for NKG2E, a protein initially identified in NK cells, is more important than both two other genes in glioblastomas aggressiveness. Indeed, KLRC3 silencing decreased self-renewal capacity, invasion, proliferation, radioresistance and tumourigenicity of U87-MG glioblastoma cell line. For the first time we report that KLRC3 gene expression is linked to glioblastoma aggressiveness and could be a new potential therapeutic target to attenuate glioblastoma.
Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Carcinogénesis/genética , Carcinogénesis/patología , Glioblastoma/genética , Glioblastoma/patología , Subfamília C de Receptores Similares a Lectina de Células NK/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Células Clonales , Femenino , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Ratones Desnudos , Subfamília C de Receptores Similares a Lectina de Células NK/metabolismo , Invasividad Neoplásica , ARN Interferente Pequeño/metabolismo , Tolerancia a Radiación , Transducción de Señal/genéticaRESUMEN
The transfer of exosomes containing both genetic and protein materials is necessary for the control of the cancer cell microenvironment to promote tumor angiogenesis. The nature and function of proteins found in the exosomal cargo, and the mechanism of their action in membrane transport and related signaling events are not clearly understood. In this study, we demonstrate, in human lung cancer A549 cells, that the exosome release mechanism is closely linked to the multifaceted receptor sortilin (also called neurotensin receptor 3). Sortilin is already known to be important for cancer cell function. Here, we report for the first time its role in the assembly of a tyrosine kinase complex and subsequent exosome release. This new complex (termed the TES complex) is found in exosomes and results in the linkage of the two tyrosine kinase receptors TrkB (also known as NTRK2) and EGFR with sortilin. Using in vitro models, we demonstrate that this sortilin-containing complex exhibits a control on endothelial cells and angiogenesis activation through exosome transfer.
Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Receptores ErbB/metabolismo , Exosomas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/genética , Línea Celular Tumoral , Movimiento Celular , Células Endoteliales/enzimología , Células Endoteliales/metabolismo , Receptores ErbB/genética , Exosomas/enzimología , Humanos , Glicoproteínas de Membrana/genética , Unión Proteica , Proteínas Tirosina Quinasas/genética , Receptor trkB , Transducción de SeñalRESUMEN
OBJECTIVES: Idiopathic inflammatory myopathies (IIM) are heterogeneous autoimmune diseases with wide clinical spectrum that may lead to delayed diagnosis. The aim of this study was to examine the impact of IIM-specific dot-blot assay on diagnostic process of patients presenting with muscular or systemic symptoms evocating of IIM. METHODS: We collected all the prescriptions of an IIM specific dot-blot assay (8 autoantigens including Jo-1, PL-7, PL-12, SRP, Mi-2, Ku, PM/Scl and Scl-70) over a 38-month period. RESULTS: 316 myositis dot-blot assays (MSD) were performed in 274 patients (156 women, mean age 53±10.6 years) referring for muscular and/or systemic symptoms suggesting IIM. The timing of dot prescription through the diagnostic process was highly variable: without (35%), concomitantly (16%) or after electromyographic studies (35%). Fifty-nine patients (22%) had IIM according to Bohan and Peter's criteria. Among them, 29 (49%) had positive dot (8 Jo-1, 6 PM-Scl, 5 PL-12, 5 SRP, 2 Mi-2, 2 PL-7 and 1 Ku). Various other diagnoses were performed including 35 autoimmune disease or granulomatosis (12%), 19 inflammatory rheumatic disease (7%), 16 non inflammatory muscular disorders (6%), 10 drug-induced myalgia (4%), 11 infectious myositis (4%). Except 11 borderline SRP results and one transient PM-Scl, MSD was positive only in one case of IIM. Dot allowed clinicians to correct diagnosis in 4 cases and improved the diagnosis of IIM subtypes in 4 cases. CONCLUSIONS: This study reflects the interest of myositis dot in the rapid diagnosis process of patients with non-specific muscular symptoms leading to various diagnoses including IIM.
Asunto(s)
Autoanticuerpos/sangre , Hospitales Universitarios , Immunoblotting , Miositis/diagnóstico , Miositis/terapia , Adulto , Biomarcadores/sangre , Diagnóstico Diferencial , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Miositis/sangre , Miositis/inmunología , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is a fatal malignancy that needs to identify new targets for additional therapeutic options. This study aimed to clarify the clinical and biological significance of endogenous neurotrophin (nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF)) in DLBCL biopsy samples and cell lines. METHODS: We analysed expression of NGF, BDNF, and their receptors (Trk, p75(NTR)) in 51 biopsies and cell lines by immunohistochemistry, immunofluorescence, and western blotting. To investigate the biological role of BDNF/TrkB/p75(NTR) axis, effects of neurotrophin signalling inhibition were determined on tumour cell survival and vascular endothelial growth factor (VEGF) secretion. The pharmacological pan-Trk inhibitor K252a was used for in vitro and in vivo studies. RESULTS: A BDNF/TrkB axis was expressed in all biopsies, which was independent of the germinal centre B-cell (GCB)/non-GCB profile. p75(NTR), TrkB, and BDNF tumour scores were significantly correlated and high NGF expression was significantly associated with MUM1/IRF4, and the non-GCB subtype. Diffuse large B-cell lymphoma cell lines co-expressed neurotrophins and their receptors. The full-length TrkB receptor was found in all cell lines, which was also phosphorylated at Tyr-817. p75(NTR) was associated to Trk and not to its cell death co-receptor sortilin. In vitro, inhibition of neurotrophin signalling induced cell apoptosis. K252a caused cell apoptosis, decreased VEGF secretion, and potentiated rituximab effect, notably in less rituximab-sensitive cells. In vivo, K252a significantly reduced tumour growth and potentiated the effects of rituximab in a GCB-DLBCL xenograft model. CONCLUSIONS: This work argues for a pro-survival role of endogenous neurotrophins in DLBCLs and inhibition of Trk signalling might be a potential treatment strategy for rituximab resistant subgroups.
Asunto(s)
Apoptosis , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Carbazoles/farmacología , Alcaloides Indólicos/farmacología , Linfoma de Células B Grandes Difuso/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptor trkB/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antineoplásicos/farmacología , Biopsia , Línea Celular Tumoral , Supervivencia Celular , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/patología , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Receptor trkB/antagonistas & inhibidores , Rituximab/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Despite effective treatments, relapse of colorectal cancer (CRC) is frequent, in part caused by the existence of tumor-initiating cells (TICs). Different subtypes of TICs, quiescent and activated, coexist in tumors, defining the tumor aggressiveness and therapeutic response. These subtypes have been sorted by hyperlayer sedimentation field-flow fractionation (SdFFF) from WiDr and HCT116 cell lines. On the basis of a new strategy, including TIC SdFFF sorting, 3D Matrigel amplification, and grafting of corresponding TIC colonies on the chick chorioallantoic membrane (CAM), specific tumor matrices could be obtained. If tumors had similar architectural structure with vascularization by the host system, they had different proliferative indices in agreement with their initial quiescent or activated state. Protein analysis also revealed that tumors obtained from a population enriched for "activated" TICs lost "stemness" properties and became invasive. In contrast, tumors obtained from a population enriched for "quiescent" TICs kept their stemness properties and seemed to be less proliferative and invasive. Then, it was possible to produce different kinds of tumor which could be used as selective supports to study carcinogenesis and therapy sensitivity.
Asunto(s)
Biomarcadores de Tumor/genética , Separación Celular/métodos , Neoplasias Colorrectales/diagnóstico , Modelos Biológicos , Células Madre Neoplásicas/clasificación , Animales , Biomarcadores de Tumor/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Línea Celular Tumoral , Movimiento Celular , Separación Celular/instrumentación , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/patología , Colágeno/química , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Combinación de Medicamentos , Fraccionamiento de Campo-Flujo/instrumentación , Fraccionamiento de Campo-Flujo/métodos , Expresión Génica , Células HCT116 , Humanos , Queratina-20/genética , Queratina-20/metabolismo , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Laminina/química , Invasividad Neoplásica , Células Madre Neoplásicas/patología , Neovascularización Patológica/patología , Proteoglicanos/químicaRESUMEN
Neurotensin, a neuropeptide growth factor, and its two specific neurotensin receptors, NTSR1 and NTSR2, were shown to be expressed by human B cell lines. Another NTSR, sortilin, which is common to neurotensin and neurotrophins, was also detected as we have previously described. Neurotensin was functional in B cell lines; it induced their proliferation and inhibited apoptosis induced by serum deprivation or Fas activation. Quantitative study of gene expression in two malignant B cell diseases showed that NTSR2 was overexpressed, NTSR1 decreased, and neurotensin was unexpressed in B cell leukemia patient's cells, as compared with healthy B cells. However, these expressions did not significantly change in large diffuse B cell lymphoma lymph nodes compared with benign ones. This study points out that neurotensin and its two specific receptors are expressed in human B lymphocytes. Such expressions were not described, and their relationship in B cell diseases, especially in chronic B cell leukemia, needs to be considered further in regard to these findings.
Asunto(s)
Linfocitos B/metabolismo , Regulación Neoplásica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/genética , Linfoma de Células B Grandes Difuso/genética , Neurotensina/genética , Receptores de Neurotensina/genética , Apoptosis , Linfocitos B/patología , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patología , Estudios de Casos y Controles , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/patología , Neurotensina/metabolismo , Especificidad de Órganos , Cultivo Primario de Células , Receptores de Neurotensina/metabolismo , Transducción de Señal , Receptor fas/genética , Receptor fas/metabolismoRESUMEN
Current therapies that target the B-cell receptor pathway or the inhibition of anti-apoptotic proteins do not prevent the progressive forms of chronic lymphocytic leukemia (CLL), have low long-term efficacy and are subject to therapeutic resistance. Deciphering the mechanisms of leukemic cell survival and searching for new specific targets therefore remain major challenges to improve the management of this disease. It was evidenced that NTSR2 (neurotensin receptor 2), through the recruitment of TRKB (tropomyosin related kinase B), induces survival pathways in leukemic B cells. We have investigated the therapeutic potential of this protein complex as a new target. The binding domain of NTSR2 and TRKB was identified and a peptide targeting the latter was designed. The peptide binds TRKB and efficiently decreases the interaction of the two proteins. It is also effectively internalized by CLL-B cells in which it notably affects Src family kinase signaling and anti-apoptotic proteins levels. It demonstrated a cytotoxic effect both in vitro on the MEC-1 cell line and ex vivo on a cohort of 30 CLL patients. Altogether, these results underline the therapeutic potential of the NTSR2/TRKB protein complex as a target in CLL and open new perspectives for the development of targeted therapies.
Asunto(s)
Leucemia Linfocítica Crónica de Células B , Humanos , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Linfocitos B/metabolismo , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/metabolismo , Péptidos/metabolismoRESUMEN
The resistance of Chronic Lymphocytic Leukemia (CLL) B-cells to cell death is mainly attributed to interactions within their microenvironment, where they interact with various types of cells. Within this microenvironment, CLL-B-cells produce and bind cytokines, growth factors, and extracellular vesicles (EVs). In the present study, EVs purified from nurse-like cells and M2-polarized THP1 cell (M2-THP1) cultures were added to CLL-B-cells cultures. EVs were rapidly internalized by B-cells, leading to a decrease in apoptosis (P = 0.0162 and 0.0469, respectively) and an increased proliferation (P = 0.0335 and 0.0109). Additionally, they induced an increase in the resistance of CLL-B-cells to Ibrutinib, the Bruton kinase inhibitor in vitro (P = 0.0344). A transcriptomic analysis showed an increase in the expression of anti-apoptotic gene BCL-2 (P = 0.0286) but not MCL-1 and an increase in the expression of proliferation-inducing gene APRIL (P = 0.0286) following treatment with EVs. Meanwhile, an analysis of apoptotic protein markers revealed increased amounts of IGFBP-2 (P = 0.0338), CD40 (P = 0.0338), p53 (P = 0.0219) and BCL-2 (P = 0.0338). Finally, exploration of EVs protein content by mass spectrometry revealed they carry various proteins involved in known oncogenic pathways and the RNAseq analysis of CLL-B-cells treated or not with NLCs EVs show various differentially expressed genes.
Asunto(s)
Vesículas Extracelulares , Leucemia Linfocítica Crónica de Células B , Macrófagos , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Linfocítica Crónica de Células B/genética , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo , Apoptosis , Supervivencia Celular , Proliferación CelularRESUMEN
Microglial cells constitute the first line of defense of the central nervous system (CNS) against microbial invasion. Pathogens are detected thanks to an array of innate immune receptors termed pattern recognition receptors (PRRs). PRRs have been thoroughly characterized in bone marrow-derived macrophages, but the PRRs repertoire and functionality in microglial cells remain largely unknown. Microglial cells express various Toll-like Receptors and the Nod1/2 receptors. Recently, a novel innate immune signalling pathway, the inflammasome pathway has been uncovered. Inflammasome activation leads to caspase-1 activation, release of the proinflammatory cytokines, IL-1ß and IL-18 and cell death in a process termed pyroptosis. One inflammasome receptor, NLRP3, has been characterized in microglial cells and associated with response to infections and in the initiation of neuro-degeneration in an Alzheimer's disease model. Legionella pneumophila (L.pneumophila) is a flagellated bacterium replicating within macrophages. In bone marrow-derived macrophages, L. pneumophila is detected in a flagellin-dependent manner by the Naip5-NLRC4 (Ipaf) inflammasome pathway. In this study, we decided to use L. pneumophila to investigate the presence and the functionality of this inflammasome in primary murine microglial cells. We show that microglial cells detect L. pneumophila infection in a flagellin-dependent manner leading to caspase-1-mediated bacterial growth restriction, infected cell death and secretion of the proinflammatory cytokines IL-1ß and IL18. Overall, our data demonstrate that microglial cells have a functional Naip5-NLRC4 inflammasome likely to be important to monitor and clear CNS infections by flagellated bacteria.
Asunto(s)
Flagelina/metabolismo , Inhibidores de Crecimiento/metabolismo , Inflamasomas/metabolismo , Legionella pneumophila/patogenicidad , Enfermedad de los Legionarios/metabolismo , Enfermedad de los Legionarios/microbiología , Microglía/citología , Microglía/microbiología , Animales , Animales Recién Nacidos , Apoptosis , Proteínas Reguladoras de la Apoptosis/fisiología , Proteínas de Unión al Calcio/fisiología , Células Cultivadas , Flagelina/farmacología , Inhibidores de Crecimiento/fisiología , Inflamasomas/fisiología , Legionella pneumophila/crecimiento & desarrollo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/metabolismo , Proteína Inhibidora de la Apoptosis Neuronal/fisiologíaRESUMEN
Objective: To identify the key coding genes underlying the biomarkers and pathways associated with giant cell arteritis (GCA), we performed an in situ spatial profiling of molecules involved in the temporal arteries of GCA patients and controls. Furthermore, we performed pharmacogenomic network analysis to identify potential treatment targets. Methods: Using human formalin-fixed paraffin-embedded temporal artery biopsy samples (GCA, n = 9; controls, n = 7), we performed a whole transcriptome analysis using the NanoString GeoMx Digital Spatial Profiler. In total, 59 regions of interest were selected in the intima, media, adventitia, and perivascular adipose tissue (PVAT). Differentially expressed genes (DEGs) (fold-change > 2 or < -2, p-adjusted < 0.01) were compared across each layer to build a spatial and pharmacogenomic network and to explore the pathophysiological mechanisms of GCA. Results: Most of the transcriptome (12,076 genes) was upregulated in GCA arteries, compared to control arteries. Among the screened genes, 282, 227, 40, and 5 DEGs were identified in the intima, media, adventitia, and PVAT, respectively. Genes involved in the immune process and vascular remodeling were upregulated within GCA temporal arteries but differed across the arterial layers. The immune-related functions and vascular remodeling were limited to the intima and media. Conclusion: This study is the first to perform an in situ spatial profiling characterization of the molecules involved in GCA. The pharmacogenomic network analysis identified potential target genes for approved and novel immunotherapies.
Asunto(s)
Arteritis de Células Gigantes , Humanos , Arteritis de Células Gigantes/patología , Arterias Temporales , Remodelación Vascular , Arterias/patología , Biomarcadores/metabolismoRESUMEN
Recently, cancer stem cells (CSCs) have been identified in many types of cancers, such as colorectal cancer (CRC). CSCs seem to be involved in initiation, growth, and tumor metastasis, as well as in radio- and chemotherapy failures. CSCs appears as new biological targets for cancer therapy, requiring the development of noninvasive cell sorting methods. In this study, we used sedimentation field flow fractionation (SdFFF) to prepare enriched populations of CSCs from eight cell lines corresponding to different CRC grades. On the basis of phenotypic and functional characterizations, "hyperlayer" elution resulted in a fraction overexpressing CSC markers (CD44, CD166, EpCAM) for all cell lines. CSCs were eluted in the last fraction for seven out of eight cell lines, but in the first for HCT116. These results suggest, according to the literature, that two different pools of CSCs exist, quiescent and activated, which can both be sorted by SdFFF. Moreover, according to CSC properties, enriched fractions are able to form colonies.
Asunto(s)
Fraccionamiento de Campo-Flujo , Células Madre Neoplásicas/citología , Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Moléculas de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Línea Celular Tumoral , Molécula de Adhesión Celular Epitelial , Proteínas Fetales/metabolismo , Humanos , Receptores de Hialuranos/metabolismo , Células Madre Neoplásicas/metabolismoRESUMEN
The development of hypoxic areas often takes place in solid tumors and leads cells to undergo adaptive signalization like autophagy. This process is responsible for misfolded or aggregated proteins and nonfunctional organelle recycling, allowing cells to maintain their energetic status. However, it could constitute a double-edged pathway leading to both survival and cell death. So, in response to stress such as hypoxia, autophagic and apoptotic cells are often mixed. To specifically study and characterize autophagic cells and the process, we needed to develop a method able to (1) isolate autophagic subpopulation and (2) respect apoptotic and autophagic status. Sedimentation field-flow fractionation (SdFFF) was first used to monitor physical parameter changes due to the hypoxia mimetic CoCl(2) in the p53 mutated SKNBE2(c) human neuroblastoma cell line. Second, we showed that "hyperlayer" elution is able to prepare autophagic enriched populations, fraction (F3), overexpressing autophagic markers (i.e., LC3-II accumulation and punctiform organization of autophagosomes as well as cathepsin B overactivity). Conversely, the first eluted fraction exhibited apoptotic markers (caspase-3 activity and Bax increased expression). For the first time, SdFFF was employed as an analytical tool in order to discriminate apoptotic and autophagic cells, thus providing an enriched autophagic fraction consecutively to a hypoxic stress.
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Autofagia , Separación Celular/métodos , Fraccionamiento de Campo-Flujo/métodos , Caspasa 3/metabolismo , Catepsina B/metabolismo , Hipoxia de la Célula , Línea Celular Tumoral , Cobalto/metabolismo , Humanos , Mutación , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patología , Proteína p53 Supresora de Tumor/genéticaRESUMEN
Nowadays, colon cancer prognosis still difficult to predict, especially in the early stages. Recurrences remain elevated, even in the early stages after curative surgery. Carcidiag Biotechnologies has developed an immunohistochemistry (IHC) kit called ColoSTEM Dx, based on a MIX of biotinylated plant lectins that specifically detects colon cancer stem cells (CSCs) through glycan patterns that they specifically (over)express. A retrospective clinical study was carried out on tumor tissues from 208 non-chemotherapeutic-treated and 21 chemotherapeutic-treated patients with colon cancer, which were stained by IHC with the MIX. Clinical performances of the kit were determined, and prognostic and predictive values were evaluated. With 78.3% and 70.6% of diagnostic sensitivity and specificity respectively, our kit shows great clinical performances. Moreover, patient prognosis is significantly poorer when the MIX staining is "High" compared to "Low", especially at 5-years of overall survival and for early stages. The ColoSTEM Dx kit allows an earlier and a more precise determination of patients' outcome. Thus, it affords an innovating clinical tool for predicting tumor aggressiveness earlier and determining prognosis value regarding therapeutic response in colon cancer patients.
RESUMEN
BACKGROUND: The aim of this paper was to study the evolution of primary Sjögren's syndrome (pSS) immunological profile, its impact on pSS activity and long-term evolution in a bicentric cohort of French patients with pSS (n = 445, mean age 53.6 ± 14 years, mean follow-up 76.1 ± 51 months). METHODS: This is a retrospective cohort study. RESULTS: Two hundred twelve patients were Sjögren's syndrome A (SSA) positive, and 131 were both SSA and Sjögren's syndrome B (SSB) positive. Sixty-eight patients (15%) had cryoglobulinemia. Active systemic profile (i.e., hypergammaglobulinemia, rheumatoid factor (RF), and anti-Sjögren's syndrome A (anti-SSA), anti-Sjögren's syndrome B (anti-SSB) positivity), associated with multisystemic involvement, leads to an increased utilization of corticosteroid and hydroxychloroquine. Multivariate analysis pointed out independent statistical association between hypergammaglobulinemia, anti-SSA, anti-SSB, and RF. Cryoglobulinemia is associated with multi-systemic involvement, lymphoma, and pSS-related death. CONCLUSION: The subset of patients with active immunological profile is characterized by systemic complications leading to immunosuppressive drug utilization and polyclonal B-cell activation profile.
Asunto(s)
Anticuerpos Antinucleares/sangre , Factor Reumatoide/sangre , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/inmunología , Adulto , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Francia , Humanos , Hipergammaglobulinemia , Terapia de Inmunosupresión , Linfoma , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica , Pronóstico , Estudios Retrospectivos , Síndrome de Sjögren/mortalidad , Síndrome de Sjögren/fisiopatología , Síndrome de Sjögren/terapia , Análisis de SupervivenciaRESUMEN
Therapeutic resistance and infiltrative capacities justify the aggressiveness of glioblastoma. This is due to cellular heterogeneity, especially the presence of stemness-related cells, i.e. Cancer Stem Cells (CSC). Previous studies focused on autophagy and its role in CSCs maintenance; these studies gave conflicting results as they reported either sustaining or disruptive effects. In the present work, we silenced two autophagy related genes -either Beclin1 or ATG5- by shRNA and we explored the ensuing consequences on CSCs markers' expression and functionalities. Our results showed that the down regulation of autophagy led to enhancement in expression of CSCs markers, while proliferation and clonogenicity were boosted. Temozolomide (TMZ) treatment failed to induce apoptotic death in shBeclin1-transfected cells, contrary to control. We optimized the cellular subset analysis with the use of Sedimentation Field Flow Fractionation, a biological event monitoring- and cell sorting-dedicated technique. Fractograms of both shBeclin1 and shATG5 cells exhibited a shift of elution peak as compared with control cells, showing cellular dispersion and intrinsic sub-fraction modifications. The classical stemness fraction (i.e. F3) highlighted data obtained with the overall cellular population, exhibiting enhancement of stemness markers and escape from dormancy. Our results contributed to illustrate CSCs polydispersity and to show how these cells develop capacity to bypass autophagy inhibition, thanks to their acute adaptability and plasticity.