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1.
Int J Mol Sci ; 24(19)2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37834291

RESUMEN

The severity of non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to steatohepatitis, and it is not yet clearly understood which patients will progress to liver fibrosis or cirrhosis. SPARC (Secreted Protein Acidic and Rich in Cysteine) has been involved in NAFLD pathogenesis in mice and humans. The aim of this study was to investigate the role of SPARC in inflammasome activation, and to evaluate the relationship between the hepatic expression of inflammasome genes and the biochemical and histological characteristics of NAFLD in obese patients. In vitro studies were conducted in a macrophage cell line and primary hepatocyte cultures to assess the effect of SPARC on inflammasome. A NAFLD model was established in SPARC knockout (SPARC-/-) and SPARC+/+ mice to explore inflammasome activation. A hepatic RNAseq database from NAFLD patients was analyzed to identify genes associated with SPARC expression. The results were validated in a prospective cohort of 59 morbidly obese patients with NAFLD undergoing bariatric surgery. Our results reveal that SPARC alone or in combination with saturated fatty acids promoted IL-1ß expression in cell cultures. SPARC-/- mice had reduced hepatic inflammasome activation during the progression of NAFLD. NAFLD patients showed increased expression of SPARC, NLRP3, CASP1, and IL-1ß. Gene ontology analysis revealed that genes positively correlated with SPARC are linked to inflammasome-related pathways during the progression of the disease, enabling the differentiation of patients between steatosis and steatohepatitis. In conclusion, SPARC may play a role in hepatic inflammasome activation in NAFLD.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Obesidad Mórbida , Animales , Humanos , Ratones , Inflamasomas/metabolismo , Hígado/metabolismo , Cirrosis Hepática/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Obesidad Mórbida/metabolismo , Osteonectina/genética , Osteonectina/metabolismo , Estudios Prospectivos
2.
Gut ; 70(7): 1362-1374, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33106353

RESUMEN

OBJECTIVE: The RHO family of GTPases, particularly RAC1, has been linked with hepatocarcinogenesis, suggesting that their inhibition might be a rational therapeutic approach. We aimed to identify and target deregulated RHO family members in human hepatocellular carcinoma (HCC). DESIGN: We studied expression deregulation, clinical prognosis and transcription programmes relevant to HCC using public datasets. The therapeutic potential of RAC1 inhibitors in HCC was study in vitro and in vivo. RNA-Seq analysis and their correlation with the three different HCC datasets were used to characterise the underlying mechanism on RAC1 inhibition. The therapeutic effect of RAC1 inhibition on liver fibrosis was evaluated. RESULTS: Among the RHO family of GTPases we observed that RAC1 is upregulated, correlates with poor patient survival, and is strongly linked with a prooncogenic transcriptional programme. From a panel of novel RAC1 inhibitors studied, 1D-142 was able to induce apoptosis and cell cycle arrest in HCC cells, displaying a stronger effect in highly proliferative cells. Partial rescue of the RAC1-related oncogenic transcriptional programme was obtained on RAC1 inhibition by 1D-142 in HCC. Most importantly, the RAC1 inhibitor 1D-142 strongly reduce tumour growth and intrahepatic metastasis in HCC mice models. Additionally, 1D-142 decreases hepatic stellate cell activation and exerts an anti-fibrotic effect in vivo. CONCLUSIONS: The bioinformatics analysis of the HCC datasets, allows identifying RAC1 as a new therapeutic target for HCC. The targeted inhibition of RAC1 by 1D-142 resulted in a potent antitumoural effect in highly proliferative HCC established in fibrotic livers.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Guanidinas/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Proteína de Unión al GTP rac1/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Carcinogénesis/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/secundario , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Biología Computacional , Bases de Datos Genéticas , Inhibidores Enzimáticos/uso terapéutico , Guanidinas/farmacología , Células Estrelladas Hepáticas/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Ratones , Terapia Molecular Dirigida , Trasplante de Neoplasias , Transcriptoma/efectos de los fármacos , Proteína de Unión al GTP rac1/genética , Proteínas de Unión al GTP rho/antagonistas & inhibidores , Proteínas de Unión al GTP rho/genética
3.
Liver Int ; 41(7): 1677-1693, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33641248

RESUMEN

BACKGROUND AND AIMS: Non-alcoholic fatty liver (NAFLD) and its more serious form non-alcoholic steatohepatitis increase risk of hepatocellular carcinoma (HCC). Lipid metabolic alterations and its role in HCC development remain unclear. SPARC (Secreted Protein, Acidic and Rich in Cysteine) is involved in lipid metabolism, NAFLD and diabetes, but the effects on hepatic lipid metabolism and HCC development is unknown. The aim of this study was to evaluate the role of SPARC in HCC development in the context of NAFLD. METHODS: Primary hepatocyte cultures from knockout (SPARC-/- ) or wild-type (SPARC+/+ ) mice, and HepG2 cells were used to assess the effects of free fatty acids on lipid accumulation, expression of lipogenic genes and de novo triglyceride (TG) synthesis. A NAFLD-HCC model was stabilized on SPARC-/- or SPARC+/+ mice. Correlations among SPARC, lipid metabolism-related gene expression patterns and clinical prognosis were studied using HCC gene expression dataset. RESULTS: SPARC-/- mice increases hepatic lipid deposits over time. Hepatocytes from SPARC-/- mice or inhibition of SPARC by an antisense adenovirus in HepG2 cells resulted in increased TG deposit, expression of lipid-related genes and nuclear translocation of SREBP1c. Human HCC database analysis revealed that SPARC negatively correlated with genes involved in lipid metabolism, and with poor survival. In NAFLD-HCC murine model, the absence of SPARC accelerates HCC development. RNA-seq study revealed that pathways related to lipid metabolism, cellular detoxification and proliferation were upregulated in SPARC-/- tumour-bearing mice. CONCLUSIONS: The absence of SPARC is associated with an altered hepatic lipid metabolism, and an accelerated NAFLD-related HCC development.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Animales , Carcinoma Hepatocelular/metabolismo , Metabolismo de los Lípidos , Lípidos , Hígado/metabolismo , Neoplasias Hepáticas/metabolismo , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Osteonectina/genética , Osteonectina/metabolismo
4.
J Hepatol ; 71(1): 78-90, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30880225

RESUMEN

BACKGROUND & AIMS: A causal link has recently been established between epigenetic alterations and hepatocarcinogenesis, indicating that epigenetic inhibition may have therapeutic potential. We aimed to identify and target epigenetic modifiers that show molecular alterations in hepatocellular carcinoma (HCC). METHODS: We studied the molecular-clinical correlations of epigenetic modifiers including bromodomains, histone acetyltransferases, lysine methyltransferases and lysine demethylases in HCC using The Cancer Genome Atlas (TCGA) data of 365 patients with HCC. The therapeutic potential of epigenetic inhibitors was evaluated in vitro and in vivo. RNA sequencing analysis and its correlation with expression and clinical data in the TCGA dataset were used to identify expression programs normalized by Jumonji lysine demethylase (JmjC) inhibitors. RESULTS: Genetic alterations, aberrant expression, and correlation between tumor expression and poor patient prognosis of epigenetic enzymes are common events in HCC. Epigenetic inhibitors that target bromodomain (JQ-1), lysine methyltransferases (BIX-1294 and LLY-507) and JmjC lysine demethylases (JIB-04, GSK-J4 and SD-70) reduce HCC aggressiveness. The pan-JmjC inhibitor JIB-04 had a potent antitumor effect in tumor bearing mice. HCC cells treated with JmjC inhibitors showed overlapping changes in expression programs related with inhibition of cell proliferation and induction of cell death. JmjC inhibition reverses an aggressive HCC gene expression program that is also altered in patients with HCC. Several genes downregulated by JmjC inhibitors are highly expressed in tumor vs. non-tumor parenchyma, and their high expression correlates with a poor prognosis. We identified and validated a 4-gene expression prognostic signature consisting of CENPA, KIF20A, PLK1, and NCAPG. CONCLUSIONS: The epigenetic alterations identified in HCC can be used to predict prognosis and to define a subgroup of high-risk patients that would potentially benefit from JmjC inhibitor therapy. LAY SUMMARY: In this study, we found that mutations and changes in expression of epigenetic modifiers are common events in human hepatocellular carcinoma, leading to an aggressive gene expression program and poor clinical prognosis. The transcriptional program can be reversed by pharmacological inhibition of Jumonji enzymes. This inhibition blocks hepatocellular carcinoma progression, providing a novel potential therapeutic strategy.


Asunto(s)
Antineoplásicos/farmacología , Carcinogénesis , Carcinoma Hepatocelular , Epigénesis Genética/efectos de los fármacos , Histona Demetilasas con Dominio de Jumonji/antagonistas & inhibidores , Neoplasias Hepáticas , Animales , Carcinogénesis/efectos de los fármacos , Carcinogénesis/genética , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/enzimología , Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Proteína A Centromérica/genética , Descubrimiento de Drogas , Humanos , Cinesinas/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/genética , Ratones , Mutación , Pronóstico , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Transcriptoma , Quinasa Tipo Polo 1
5.
Clin Sci (Lond) ; 133(2): 351-365, 2019 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-30626728

RESUMEN

Obesity, metabolic syndrome, and type 2 diabetes, three strongly interrelated diseases, are associated to increased morbidity and mortality worldwide. The pathogenesis of obesity-associated disorders is still under study. Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein expressed in many cell types including adipocytes, parenchymal, and non-parenchymal hepatic cells and pancreatic cells. Studies have demonstrated that SPARC inhibits adipogenesis and promotes insulin resistance; in addition, circulating SPARC levels were positively correlated with body mass index in obese individuals. Therefore, SPARC is being proposed as a key factor in the pathogenesis of obesity-associated disorders. The aim of this study is to elucidate the role of SPARC in glucose homeostasis. We show here that SPARC null (SPARC-/-) mice displayed an abnormal insulin-regulated glucose metabolism. SPARC-/- mice presented an increased adipose tissue deposition and an impaired glucose homeostasis as animals aged. In addition, the absence of SPARC worsens high-fat diet-induced diabetes in mice. Interestingly, although SPARC-/- mice on high-fat diet were sensitive to insulin they showed an impaired insulin secretion capacity. Of note, the expression of glucose transporter 2 in islets of SPARC-/- mice was dramatically reduced. The present study provides the first evidence that deleted SPARC expression causes diabetes in mice. Thus, SPARC deficient mice constitute a valuable model for studies concerning obesity and its related metabolic complications, including diabetes.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Experimental/sangre , Insulina/sangre , Islotes Pancreáticos/metabolismo , Osteonectina/metabolismo , Envejecimiento/sangre , Animales , Biomarcadores/sangre , Diabetes Mellitus Experimental/genética , Dieta Alta en Grasa , Sacarosa en la Dieta , Transportador de Glucosa de Tipo 2/metabolismo , Homeostasis , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Osteonectina/deficiencia , Osteonectina/genética , Vías Secretoras
6.
Medicina (B Aires) ; 78(1): 29-32, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29360073

RESUMEN

Hepatocellular carcinoma (HCC) is the second cause of cancer-related death in the world and is the main cause of death in cirrhotic patients. Unfortunately, the incidence of HCC has grown significantly in the last decade. Curative treatments such as surgery, liver transplantation or percutaneous ablation can only be applied in less than 30% of cases. The multikinase inhibitor sorafenib is the first line therapy for advanced HCC. Regorafenib is the standard of care for second-line patients. However, novel and more specific potent therapeutic approaches for advanced HCC are still needed. The liver constitutes a unique immunological microenvironment, although anti-tumor immunity seems to be feasible with the use of checkpoint inhibitors such as nivolumab. Efficacy may be further increased by combining checkpoint inhibitors or by applying loco-regional treatments. The success of immune checkpoint blockade has renewed interest in immunotherapy in HCC.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Inmunoterapia/métodos , Neoplasias Hepáticas/tratamiento farmacológico , Ensayos Clínicos como Asunto , Humanos , Nivolumab/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Piridinas/uso terapéutico , Sorafenib/uso terapéutico
7.
Medicina (B Aires) ; 76(5): 307-314, 2016.
Artículo en Español | MEDLINE | ID: mdl-27723619

RESUMEN

In recent years immunotherapy has revolutionized the treatment of patients with advanced cancer. The increased knowledge in the tumor immune-biology has allowed developing rational treatments by manipulation of the immune system with significant clinical impact. This rapid development has significantly changed the prognosis of many tumors without treatment options up to date. Other strategies have explored the use of therapeutic vaccines based on dendritic cells (DC) by inducing antitumor immunity. DC are cells of hematopoietic origin, constitutively expressing molecules capable to present antigens, that are functionally the most potent inducers of the activation and proliferation of antigen specific T lymphocytes. The CD8+ T cells proliferate and acquire cytotoxic capacity after recognizing their specific antigen presented on the surface of DC, although only some types of DC can present antigens internalized from outside the cell to precursors of cytotoxic T lymphocytes (this function is called cross-presentation) requiring translocation mechanisms of complex antigens. The induction of an effective adaptive immune response is considered a good option given its specificity, and prolonged duration of response. The DC, thanks to its particular ability of antigen presentation and lymphocyte stimulation, are able to reverse the poor antitumor immune response experienced by patients with cancer. The DC can be obtained from various sources, using different protocols to generate differentiation and maturation, and are administered by various routes such as subcutaneous, intravenous or intranodal. The wide variety of protocols resulted in heterogeneous clinical responses.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Neoplasias/terapia , Vacunación/métodos , Presentación de Antígeno/inmunología , Antígenos de Neoplasias/inmunología , Humanos , Neoplasias/inmunología , Linfocitos T/inmunología
9.
Methods Cell Biol ; 170: 189-202, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35811099

RESUMEN

Stem Cell based-therapy is an active area of research in regenerative medicine. Mesenchymal stem/stromal cells (MSCs) are multipotent adult stem/progenitor cells, which could be easily expanded in vitro and have the ability to selectively migrate toward injured tissues, evade the immune system, and secrete trophic factors to support the repair of damaged tissues. The use of MSCs for cell and regenerative purposes has garnered the attention of scientists and clinicians. However, one of the most important issues before use MSCs in clinical practice is to standardize a number of aspects related to the source of MSCs, culture conditions, pre-condition protocols before transplantation, administration route, doses, or treatment duration. In this chapter, we described two standard protocols to isolate MSCs from bone marrow and umbilical cord connective tissue. In addition, basic characterization including immunophenotyping by flow cytometry and differentiation capability is also described.


Asunto(s)
Células Madre Mesenquimatosas , Adulto , Diferenciación Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Células Cultivadas , Tejido Conectivo , Humanos , Medicina Regenerativa
10.
Sci Rep ; 11(1): 6310, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33737571

RESUMEN

Hepatocellular carcinoma (HCC) arises in the setting of advanced liver fibrosis, a dynamic and complex inflammatory disease. The tumor microenvironment (TME) is a mixture of cellular components including cancer cells, cancer stem cells (CSCs), tumor-associated macrophages (TAM), and dendritic cells (DCs), which might drive to tumor progression and resistance to therapies. In this work, we study the effects of 4-methylumbelliferone (4Mu) on TME and how this change could be exploited to promote a potent immune response against HCC. First, we observed that 4Mu therapy induced a switch of hepatic macrophages (Mϕ) towards an M1 type profile, and HCC cells (Hepa129 cells) exposed to conditioned medium (CM) derived from Mϕ treated with 4Mu showed reduced expression of several CSCs markers and aggressiveness. HCC cells incubated with CM derived from Mϕ treated with 4Mu grew in immunosuppressed mice while presented delayed tumor progression in immunocompetent mice. HCC cells treated with 4Mu were more susceptible to phagocytosis by DCs, and when DCs were pulsed with HCC cells previously treated with 4Mu displayed a potent antitumoral effect in therapeutic vaccination protocols. In conclusion, 4Mu has the ability to modulate TME into a less hostile milieu and to potentiate immunotherapeutic strategies against HCC.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Himecromona/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Microambiente Tumoral/efectos de los fármacos , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Células Dendríticas/efectos de los fármacos , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Humanos , Himecromona/efectos adversos , Inmunidad/efectos de los fármacos , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Ratones , Células Madre Neoplásicas/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Macrófagos Asociados a Tumores/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Medicina (B Aires) ; 80(6): 696-702, 2020.
Artículo en Español | MEDLINE | ID: mdl-33254115

RESUMEN

Cell therapy and regenerative medicine are currently active areas for biomedical research. In most tissues, there are self-repair mechanisms carried out mainly by resident stem cells that can differentiate and replace dead cells or secrete trophic factors that stimulate the regenerative process. These mechanisms often fail in degenerative diseases; thus it is postulated that exogenous cell therapy can contribute to tissue regeneration and repair. Mesenchymal stem cells (MSCs) are multipotent adult stem/progenitor cells, which could be easily expanded in vitro and have the ability to selectively migrate toward injured tissues, evade the immune system recognition, and secrete trophic factors to support tissue repair. Furthermore, MSCs could be engineered for the delivery of therapeutic genes. The main sources for MSCs are bone marrow, adipose tissue, and umbilical cord. A number of pre-clinical and clinical studies have shown that MSCs therapy is safe for both autologous and allogeneic uses. This review summarizes information about the properties of MSCs and their therapeutic potential for a broad spectrum of diseases. We also present here the last data about clinical trials that position the use of MSCs as an interesting tool for tissue regeneration and the treatment of inflammatory diseases.


La terapia celular y la medicina regenerativa son áreas en gran desarrollo en la investigación biomédica. En la mayoría de los tejidos existen mecanismos de auto-reparación llevados a cabo, principalmente, por células madre o progenitoras residentes con capacidad para diferenciarse y reemplazar a las células dañadas o para secretar factores tróficos que induzcan el proceso regenerativo. Dado que estos mecanismos de reparación no siempre son suficientes, se postula que la terapia celular puede contribuir a la regeneración de los tejidos sometidos a injuria. Las células madre/estromales mesenquimales (MSCs, del inglés Mesenchymal Stem/Stromal Cells) son un tipo de progenitor adulto multipotente, que tienen la capacidad de expandirse in vitro con facilidad cuando son aisladas de su nicho in vivo, migrar selectivamente a los tejidos lesionados, modular y evadir el sistema inmunológico, y secretar factores tróficos que ayudan a la reparación tisular. Asimismo, la fácil manipulación ex vivo permitiría también usarlas como vehículos de genes terapéuticos. Las principales fuentes de obtención son la médula ósea, el tejido adiposo y cordón umbilical. Los numerosos estudios pre-clínicos y clínicos han demostrado que las MSCs parecieran ser seguras tanto para uso autólogo como alogénico. En este trabajo se resumen las propiedades de las MSCs y su potencial terapéutico para una amplia gama de enfermedades, también presentamos los distintos ensayos clínicos avanzados que las posicionan en el ámbito biomédico como una herramienta interesante para la regeneración de tejidos y el tratamiento de enfermedades inflamatorias.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Medicina Regenerativa , Ingeniería de Tejidos
12.
Clin Liver Dis (Hoboken) ; 16(3): 96-100, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33005389

RESUMEN

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13.
Oncotarget ; 8(46): 80235-80248, 2017 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-29113298

RESUMEN

New therapies are needed for advanced hepatocellular carcinoma (HCC) and the use of mesenchymal stromal cells (MSCs) carrying therapeutic genes is a promising strategy. HCC produce cytokines recruiting MSCs to the tumor milieu and modifying its biological properties. Our aim was to study changes generated on human MSCs exposed to conditioned media (CM) derived from human HCC fresh samples and xenografts. All CM shared similar cytokines expression pattern including CXCL1-2-3/GRO, CCL2/MCP-1 and CXCL8/IL-8 being the latter with the highest concentration. Neutralizing and knockdown experiments of CCL2/MCP-1, CXCL8/IL-8, CXCR1 and CXCR2 reduced in vitro MSC migration of ≥20%. Simultaneous CXCR1 and CXCR2 neutralization resulted in 50% of MSC migration inhibition. MSC stimulated with CM (sMSC) from HuH7 or HC-PT-5 showed a 2-fold increase of migration towards the CM compared with unstimulated MSC (usMSC). Gene expression profile of sMSC showed ~500 genes differentially expressed compared with usMSC, being 46 genes related with cell migration and invasion. sMSC increased fibroblasts and endothelial cells chemotaxis. Finally, sMSC with HuH7 CM and then inoculated in HCC tumor bearing-mice did not modify tumor growth. In this work we characterized factors produced by HCC responsible for the changes in MSC chemotactic capacity with would have an impact on therapeutic use of MSCs for human HCC.

14.
Medicina (B.Aires) ; Medicina (B.Aires);80(6): 696-702, dic. 2020. graf
Artículo en Español | LILACS | ID: biblio-1250293

RESUMEN

Resumen La terapia celular y la medicina regenerativa son áreas en gran desarrollo en la investigación biomédica. En la mayoría de los tejidos existen mecanismos de auto-reparación llevados a cabo, principalmente, por células madre o progenitoras residentes con capacidad para diferenciarse y reemplazar a las células dañadas o para secretar factores tróficos que induzcan el proceso regenerativo. Dado que estos mecanismos de reparación no siempre son suficientes, se postula que la terapia celular puede contribuir a la regeneración de los tejidos sometidos a injuria. Las células madre/estromales mesenquimales (MSCs, del inglés Mesenchymal Stem/Stromal Cells) son un tipo de progenitor adulto multipotente, que tienen la capacidad de expandirse in vitro con facilidad cuando son aisladas de su nicho in vivo, migrar selectivamente a los tejidos lesionados, modular y evadir el sistema inmunológico, y secretar factores tróficos que ayudan a la reparación tisular. Asimismo, la fácil manipulación ex vivo permitiría también usarlas como vehículos de genes terapéuticos. Las principales fuentes de obtención son la médula ósea, el tejido adiposo y cordón umbilical. Los numerosos estudios pre-clínicos y clínicos han demostrado que las MSCs parecieran ser seguras tanto para uso autólogo como alogénico. En este trabajo se resumen las propiedades de las MSCs y su potencial terapéutico para una amplia gama de enfermedades, también presentamos los distintos ensayos clínicos avanzados que las posicionan en el ámbito biomédico como una herramienta interesante para la regeneración de tejidos y el tratamiento de enfermedades inflamatorias.


Abstract Cell therapy and regenerative medicine are currently active areas for biomedical research. In most tissues, there are self-repair mechanisms carried out mainly by resident stem cells that can differentiate and replace dead cells or secrete trophic factors that stimulate the regenerative process. These mechanisms often fail in degenerative diseases; thus it is postulated that exogenous cell therapy can contribute to tissue regeneration and repair. Mesenchymal stem cells (MSCs) are multipotent adult stem/progenitor cells, which could be easily expanded in vitro and have the ability to selectively migrate toward injured tissues, evade the immune system recognition, and secrete trophic factors to support tissue repair. Furthermore, MSCs could be engineered for the delivery of therapeutic genes. The main sources for MSCs are bone marrow, adipose tissue, and umbilical cord. A number of pre-clinical and clinical studies have shown that MSCs therapy is safe for both autologous and allogeneic uses. This review summarizes information about the properties of MSCs and their therapeutic potential for a broad spectrum of diseases. We also present here the last data about clinical trials that position the use of MSCs as an interesting tool for tissue regeneration and the treatment of inflammatory diseases.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Ingeniería de Tejidos , Medicina Regenerativa
15.
Medicina (B.Aires) ; Medicina (B.Aires);78(1): 29-32, feb. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-894543

RESUMEN

Hepatocellular carcinoma (HCC) is the second cause of cancer-related death in the world and is the main cause of death in cirrhotic patients. Unfortunately, the incidence of HCC has grown significantly in the last decade. Curative treatments such as surgery, liver transplantation or percutaneous ablation can only be applied in less than 30% of cases. The multikinase inhibitor sorafenib is the first line therapy for advanced HCC. Regorafenib is the standard of care for second-line patients. However, novel and more specific potent therapeutic approaches for advanced HCC are still needed. The liver constitutes a unique immunological microenvironment, although anti-tumor immunity seems to be feasible with the use of checkpoint inhibitors such as nivolumab. Efficacy may be further increased by combining checkpoint inhibitors or by applying loco-regional treatments. The success of immune checkpoint blockade has renewed interest in immunotherapy in HCC.


El hepatocarcinoma (HCC) es la segunda causa de muerte relacionada con el cáncer en el mundo y es la principal causa de muerte en pacientes cirróticos. Desafortunadamente, la incidencia de HCC ha crecido significativamente en la última década. Los tratamientos curativos como la cirugía, el trasplante de hígado o la ablación solo pueden aplicarse en menos del 30% de los casos. El sorafenib es el tratamiento de primera línea para el HCC avanzado, mientras que el regorafenib se reserva como segunda línea. Sin embargo, todavía son necesarios nuevos enfoques terapéuticos potentes y más específicos para el HCC avanzado. El hígado constituye un microambiente inmunológico único, aunque la inmunidad antitumoral parece ser factible mediante el uso de inhibidores de punto de control como nivolumab. La eficacia puede aumentarse adicionalmente combinando inhibidores de puntos de control inmunitario o aplicando tratamientos loco-regionales. En este sentido, el éxito del uso de anticuerpos monoclonales, que bloquean el control inmunitario, ha renovado el interés en la inmunoterapia para el HCC.


Asunto(s)
Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Antineoplásicos Inmunológicos/uso terapéutico , Inmunoterapia/métodos , Neoplasias Hepáticas/tratamiento farmacológico , Anticuerpos Monoclonales/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Piridinas/uso terapéutico , Ensayos Clínicos como Asunto , Sorafenib/uso terapéutico , Nivolumab/uso terapéutico
16.
Medicina (B.Aires) ; Medicina (B.Aires);76(5): 307-314, Oct. 2016. ilus
Artículo en Español | LILACS | ID: biblio-841598

RESUMEN

En los últimos años la inmunoterapia ha revolucionado el tratamiento de pacientes con cáncer avanzado. El mayor conocimiento de la biología tumoral y de la inmunología ha permitido desarrollar tratamientos racionales manipulando el sistema inmunitario con importante impacto clínico. Entre otras estrategias de inmunoterapia contra el cáncer se ha explorado el uso de vacunas terapéuticas basadas en células dendríticas (CD). Las CD son células de origen hematopoyético, que expresan constitutivamente moléculas presentadoras de antígeno, y son funcionalmente las inductoras más potentes de la activación y proliferación de linfocitos T a los que presentan antígenos. Los linfocitos T CD8+ proliferan y adquieren capacidad citotóxica cuando reconocen su antígeno específico presentado en la superficie de CD, aunque solo algunos tipos de CD pueden presentar antígenos internalizados desde el exterior celular a precursores de linfocitos T citotóxicos (a esta función se la llama presentación cruzada). Explotar la inducción de una respuesta inmunitaria adaptativa eficaz se considera una buena opción por su especificidad y prolongada duración de la respuesta. Las CD, gracias a su particular capacidad de presentación antigénica y de estimulación linfocitaria, son capaces de revertir la respuesta inmunitaria antitumoral deficiente que presentan algunos pacientes con cáncer. Las CD se pueden obtener a partir de distintas fuentes, empleando diversos protocolos para generar diferenciación y maduración, y se administran por diversas vías como son subcutánea, intravenosa o intranodal. La gran variedad de protocolos en los que se aplican las CD explica los resultados clínicos tan heterogéneos que se han comunicado hasta la fecha.


In recent years immunotherapy has revolutionized the treatment of patients with advanced cancer. The increased knowledge in the tumor immune-biology has allowed developing rational treatments by manipulation of the immune system with significant clinical impact. This rapid development has significantly changed the prognosis of many tumors without treatment options up to date. Other strategies have explored the use of therapeutic vaccines based on dendritic cells (DC) by inducing antitumor immunity. DC are cells of hematopoietic origin, constitutively expressing molecules capable to present antigens, that are functionally the most potent inducers of the activation and proliferation of antigen specific T lymphocytes. The CD8+ T cells proliferate and acquire cytotoxic capacity after recognizing their specific antigen presented on the surface of DC, although only some types of DC can present antigens internalized from outside the cell to precursors of cytotoxic T lymphocytes (this function is called cross-presentation) requiring translocation mechanisms of complex antigens. The induction of an effective adaptive immune response is considered a good option given its specificity, and prolonged duration of response. The DC, thanks to its particular ability of antigen presentation and lymphocyte stimulation, are able to reverse the poor antitumor immune response experienced by patients with cancer. The DC can be obtained from various sources, using different protocols to generate differentiation and maturation, and are administered by various routes such as subcutaneous, intravenous or intranodal. The wide variety of protocols resulted in heterogeneous clinical responses.


Asunto(s)
Humanos , Células Dendríticas/inmunología , Vacunación/métodos , Vacunas contra el Cáncer/inmunología , Neoplasias/terapia , Linfocitos T/inmunología , Presentación de Antígeno/inmunología , Antígenos de Neoplasias/inmunología , Neoplasias/inmunología
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