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1.
Mol Ther ; 31(11): 3193-3209, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37735875

RESUMO

Claudin18.2 (CLDN18.2)-specific chimeric antigen receptor (CAR-T) cells displayed limited efficacy in CLDN18.2-positive pancreatic ductal adenocarcinoma (PDAC). Strategies are needed to improve the trafficking capacity of CLDN18.2-specific CAR-T cells. PDAC has a unique microenvironment that consists of abundant cancer-associated fibroblasts (CAFs), which could secrete stromal cell-derived factor 1α (SDF-1α), the ligand of CXCR4. Then, we constructed and explored CLDN18.2-targeted CAR-T cells with CXCR4 co-expression in treating immunocompetent mouse models of PDAC. The results indicated that CXCR4 could promote the infiltration of CAR-T cells and enhance their efficacy in vivo. Mechanistically, the activation of signal transducer and activator of transcription 3 (STAT3) signaling was impaired in CXCR4 CAR-T cells, which reduced the release of inflammatory factors, such as tumor necrosis factor-α, IL-6, and IL-17A. Then, the lower release of inflammatory factors suppressed SDF-1α secretion in CAFs via the nuclear factor κB (NF-κB) pathway. Therefore, the decreased secretion of SDF-1α in feedback decreased the migration of myeloid-derived suppressor cells (MDSCs) in tumor sites. Overall, our study demonstrated that CXCR4 CAR-T cells could traffic more into tumor sites and also suppress MDSC migration via the STAT3/NF-κB/SDF-1α axis to obtain better efficacy in treating CLDN18.2-positive pancreatic cancer. Our findings provide a theoretical rationale for CXCR4 CAR-T cell therapy in PDAC.


Assuntos
Células Supressoras Mieloides , Neoplasias Pancreáticas , Receptores de Antígenos Quiméricos , Camundongos , Animais , NF-kappa B/metabolismo , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Células Supressoras Mieloides/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Movimento Celular/fisiologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Linfócitos T/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Microambiente Tumoral
2.
Endocr J ; 66(2): 175-180, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30568069

RESUMO

Cushing's syndrome (CS) is a clinical syndrome characterized by hypercortisolemia. Cyclic Cushing's syndrome (CCS), which exhibits a periodic or irregular increasing pattern in cortisol, is a rare type of Cushing's syndrome. A 37-year-old man came to our hospital because of repeated dizzy spells, weakness and hypercortisolemia lasting two weeks. Endocrinological examinations indicated CCS with periodic and intermittent increases in cortisol. Enhanced computed tomography (CT) revealed space occupying lesions on the upper lobe of left lung, and biopsy eventually proved that these were pulmonary carcinoid tumors with ectopic ACTH secretion, which was subsequently manifested a Cushing's syndrome. PET-CT, ultrasound and biopsy of the thyroid gland indicated bilateral thyroid papillary carcinoma. CT scan showed bilateral nodular hyperplasia of the adrenal gland. Enhanced magnetic resonance imaging (MRI) confirmed that the high signal disappeared on the posterior lobe of the pituitary gland and that the pituitary stalk shifted left, which was suspected to be non-functional pituitary microadenoma. The patient underwent surgery involving resection of the left upper pulmonary lobe and the mediastinal lymph node around the hilus pulmonis, which resulted in complete remission of CCS. The patient then chose elective surgery for the thyroid papillary carcinoma. An analysis of the patient's genomic DNA identified a novel mutation in PDE11A: c.2032 (exon 12) G > A, which is associated with primary pigmented nodular adrenocortical disease (PPNAD). This is a novel mutation which has been no previous public clinical report on this mutation as it relates to this disease.


Assuntos
Síndrome de Cushing/etiologia , Neoplasias Pulmonares/complicações , Tumores Neuroendócrinos/complicações , Câncer Papilífero da Tireoide/complicações , Neoplasias da Glândula Tireoide/complicações , Adulto , Síndrome de Cushing/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Tumores Neuroendócrinos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Câncer Papilífero da Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem
3.
J Cell Physiol ; 231(1): 142-51, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26060084

RESUMO

The biological activities of lanthanum chloride (LaCl3 ) and the molecular mechanisms of action underlying its anti-inflammatory, anti-hyperphosphatemic, and osteoblast-enhancing effects have been studied previously, but less is known about the effects of LaCl3 on osteoclasts. The present study used in vivo and in vitro approaches to explore the effects of LaCl3 on osteoclasts and osteolysis. The results indicated that LaCl3 concentrations that were non-cytotoxic to mouse bone marrow-derived monocytes attenuated receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis, bone resorption, mRNA expression of osteoclastogenic genes in these cells, including cathepsin K, calcitonin receptor, and tartrate-resistant acid phosphatase (TRAP). Further, LaCl3 inhibited RANKL-mediated activation of the nuclear factor-κB (NF-κB) signaling pathway, and downregulated mRNA and protein levels of nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1), and c-fos. In vivo, LaCl3 attenuated titanium (Ti) particle-induced bone loss in a murine calvarial osteolysis model. Histological analyses revealed that LaCl3 ameliorated bone destruction and decreased the number of TRAP-positive osteoclasts in this model. These results demonstrated that LaCl3 inhibited osteoclast formation, function, and osteoclast-specific gene expression in vitro, and attenuated Ti particle-induced mouse calvarial osteolysis in vivo, where the inhibition of NF-κB signaling and downregulation of NFATc1 and c-fos played an important role.


Assuntos
Lantânio/farmacologia , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/efeitos dos fármacos , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/patologia , Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Camundongos , Osteoclastos/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ligante RANK/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Int J Mol Sci ; 17(5)2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27213355

RESUMO

The clinical need for effective bone regeneration therapy remains in huge demands. However, the current "gold standard" treatments of autologous and allogeneic bone grafts may result in various complications. Furthermore, safety considerations of biomaterials and cell-based treatment require further clarification. Therefore, developing new therapies with stronger osteogenic potential and a lower incidence of complications is worthwhile. Recently, exosomes, small vesicles of endocytic origin, have attracted attention in bone regeneration field. The vesicles travel between cells and deliver functional cargoes, such as proteins and RNAs, thereby regulating targeted cells differentiation, commitment, function, and proliferation. Much evidence has demonstrated the important roles of exosomes in osteogenesis both in vitro and in vivo. In this review, we summarize the properties, origins and biogenesis of exosomes, and the recent reports using exosomes to regulate osteogenesis and promote bone regeneration.


Assuntos
Regeneração Óssea/fisiologia , Exossomos/metabolismo , Neovascularização Fisiológica/fisiologia , Osteogênese/fisiologia , Animais , Humanos
5.
Int J Mol Sci ; 17(3): 422, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27011174

RESUMO

Periodontitis is a common chronic inflammatory disease, which leads to alveolar bone resorption. Healthy and functional alveolar bone, which can support the teeth and enable their movement, is very important for orthodontic treatment. Myricetin inhibited osteoclastogenesis by suppressing the expression of some genes, signaling pathways, and cytokines. This study aimed to investigate the effects of myricetin on alveolar bone loss in an ovariectomized (OVX) mouse model of periodontitis as well as in vitro osteoclast formation and bone resorption. Twenty-four healthy eight-week-old C57BL/J6 female mice were assigned randomly to four groups: phosphate-buffered saline (PBS) control (sham) OVX + ligature + PBS (vehicle), and OVX + ligature + low or high (2 or 5 mg∙kg(-1)∙day(-1), respectively) doses of myricetin. Myricetin or PBS was injected intraperitoneally (i.p.) every other day for 30 days. The maxillae were collected and subjected to further examination, including micro-computed tomography (micro-CT), hematoxylin and eosin (H&E) staining, and tartrate-resistant acid phosphatase (TRAP) staining; a resorption pit assay was also performed in vitro to evaluate the effects of myricetin on receptor activator of nuclear factor κ-B ligand (RANKL)-induced osteoclastogenesis. Myricetin, at both high and low doses, prevented alveolar bone resorption and increased alveolar crest height in the mouse model and inhibited osteoclast formation and bone resorption in vitro. However, myricetin was more effective at high dose than at low dose. Our study demonstrated that myricetin had a positive effect on alveolar bone resorption in an OVX mouse model of periodontitis and, therefore, may be a potential agent for the treatment of periodontitis and osteoporosis.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Flavonoides/uso terapêutico , Doenças Maxilares/prevenção & controle , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/etiologia , Animais , Linhagem Celular , Feminino , Flavonoides/administração & dosagem , Flavonoides/farmacologia , Injeções Intraperitoneais , Maxila/efeitos dos fármacos , Maxila/metabolismo , Maxila/patologia , Doenças Maxilares/tratamento farmacológico , Doenças Maxilares/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese , Ovariectomia/efeitos adversos , Ligante RANK/metabolismo
6.
Biochem Biophys Res Commun ; 443(2): 658-65, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24333429

RESUMO

Bone resorption is the unique function of osteoclasts (OCs) and is critical for both bone homeostasis and pathologic bone diseases including osteoporosis, rheumatoid arthritis and tumor bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast-related diseases. In this study, we for the first time demonstrated that dioscin suppressed RANKL-mediated osteoclast differentiation and bone resorption in vitro in a dose-dependent manner. The suppressive effect of dioscin is supported by the reduced expression of osteoclast-specific markers. Further molecular analysis revealed that dioscin abrogated AKT phosphorylation, which subsequently impaired RANKL-induced nuclear factor-kappaB (NF-κB) signaling pathway and inhibited NFATc1 transcriptional activity. Moreover, in vivo studies further verified the bone protection activity of dioscin in osteolytic animal model. Together our data demonstrate that dioscin suppressed RANKL-induced osteoclast formation and function through Akt signaling cascades. Therefore, dioscin is a potential natural agent for the treatment of osteoclast-related diseases.


Assuntos
Reabsorção Óssea/metabolismo , Diosgenina/análogos & derivados , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoclastos/metabolismo , Osteoclastos/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Reabsorção Óssea/prevenção & controle , Diferenciação Celular/efeitos dos fármacos , Diosgenina/farmacologia , Diosgenina/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Camundongos , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
7.
J Clin Microbiol ; 52(5): 1730-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24574298

RESUMO

This meta-analysis included 12 studies that evaluated sonication fluid cultures (SFC) for the diagnosis of prosthetic joint infection (PJI). The pooled sensitivity and specificity were 0.80 (95% confidence interval [CI], 0.74 to 0.84) and 0.95 (CI, 0.90 to 0.98), respectively. Subgroup analyses showed that a 14-day anaerobic culture may improve sensitivity, the use of centrifugation or vortexing may improve specificity, and the use of 400 to 500 ml of Ringer's solution for containers may improve sensitivity and specificity. The best SFC cutoff was ≥5 CFU. In conclusion, SFC has high sensitivity and very high specificity for diagnosing PJI.


Assuntos
Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Idoso , Artroplastia/métodos , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Sonicação/métodos
8.
Mediators Inflamm ; 2014: 596967, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24803740

RESUMO

BACKGROUND: Coronary atherosclerotic heart disease (CHD) is one of the major concerns in type 2 diabetes (T2D). The systemic chronic inflammation has been postulated to bridge the increased risk of cardiovascular disease and T2D. We formulated that increased peripheral proinflammatory T helper subsets contributed to the development of cardiovascular complications in diabetic patients. METHODS: The frequencies of peripheral total CD4+ T helper cells, proinflammatory Th1, Th17, and Th22 subsets were determined by flow cytometry in diabetic patients with or without CHD (n = 42 and 67, resp.). RESULTS: Both peripheral frequencies and total numbers of Th1, Th17, and Th22 cells were further increased in diabetic patients with CHD. Logistic regression and categorical cross-table analysis further confirmed that increased proinflammatory Th subsets, especially Th22, were independent risk factors of cardiovascular complication in diabetes. Elevated Th subsets also correlated with increased CRP levels and the atherogenic index of plasma. Moreover, Th1 frequency and Th22 numbers demonstrated remarkable potential in predicting CHD in diabetes. CONCLUSIONS: Increased peripheral proinflammatory T helper subsets act in concert and contribute to the increased prevalence of diabetic cardiovasculopathy. The recently identified Th22 cells might play an independent role in CHD and represent a novel proxy for cardiovascular risks in diabetes.


Assuntos
Doença da Artéria Coronariana/imunologia , Diabetes Mellitus Tipo 2/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto , Idoso , Doença da Artéria Coronariana/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/imunologia , Células Th1/metabolismo , Células Th17/metabolismo
9.
Int J Mol Sci ; 15(12): 21913-34, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25464380

RESUMO

The aim of this study was to assess the effect of naringenin on osteoclastogenesis and titanium particle-induced osteolysis. Osteolysis from wear-induced particles and aseptic loosening are the most frequent late complications of total joint arthroplasty leading to revision of the prosthesis. Osteolysis during aseptic loosening is most likely due to increased bone resorption by osteoclasts. Through in vitro studies, we demonstrated that naringenin, a naturally occurring flavanone in grapefruit and tomatoes, exerts potent inhibitory effects on the ligand of the receptor activator of nuclear factor-κB (RANKL)-induced osteoclastogenesis and revealed that the mechanism of action of naringenin, which inhibited osteoclastogenesis by suppression of the p38 signaling pathway. Through in vivo studies, we proved that naringenin attenuated titanium particle-induced osteolysis in a mouse calvarial model. In general, we demonstrated that naringenin inhibited osteoclastogenesis via suppression of p38 signaling in vitro and attenuated titanium particle-induced osteolysis in vivo. This study also suggested that naringenin has significant potential for the treatment of osteolysis-related diseases caused by excessive osteoclast formation and activity.


Assuntos
Flavanonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteoclastos/enzimologia , Osteogênese/efeitos dos fármacos , Osteólise/enzimologia , Ligante RANK/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Actinas/metabolismo , Animais , Anisomicina/farmacologia , Reabsorção Óssea/complicações , Reabsorção Óssea/patologia , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Flavanonas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Osteólise/complicações , Osteólise/patologia , Titânio
10.
J Clin Microbiol ; 51(11): 3830-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23946521

RESUMO

This meta-analysis evaluated preoperative aspiration culture for diagnosing prosthetic joint infection (PJI) in total hip arthroplasty (THA) and total knee arthroplasty (TKA). The pooled sensitivity and specificity were 0.72 (95% confidence interval, 0.65 to 0.78) and 0.95 (0.93 to 0.97), respectively. Subgroup analyses revealed nonsignificant worse diagnostic performance for THA than for TKA (sensitivity, 0.70 versus 0.78; specificity, 0.94 versus 0.96). Preoperative aspiration culture has moderate to high sensitivity and very high specificity for diagnosing PJI.


Assuntos
Técnicas Microbiológicas/métodos , Cuidados Pré-Operatórios/métodos , Infecções Relacionadas à Prótese/diagnóstico , Manejo de Espécimes/métodos , Idoso , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Feminino , Humanos , Masculino , Sensibilidade e Especificidade
11.
Acta Pharmacol Sin ; 34(11): 1457-66, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24056707

RESUMO

AIM: To investigate the roles of the calcineurin/nuclear factor of activated T cells (NFAT) pathway in regulation of wear particles-induced cytokine release and osteoclastogenesis from mouse bone marrow macrophages in vitro. METHODS: Osteoclasts were induced from mouse bone marrow macrophages (BMMs) in the presence of 100 ng/mL receptor activator of NF-κB ligand (RANKL). Acridine orange staining and MTT assay were used to detect the cell viability. Osteoclastogenesis was determined using TRAP staining and RT-PCR. Bone pit resorption assay was used to examine osteoclast phenotype. The expression and cellular localization of NFATc1 were examined using RT-PCR and immunofluorescent staining. The production of TNFα was analyzed with ELISA. RESULTS: Titanium (Ti) or polymethylmethacrylate (PMMA) particles (0.1 mg/mL) did not significantly change the viability of BMMs, but twice increased the differentiation of BMMs into mature osteoclasts, and markedly increased TNF-α production. The TNF-α level in the PMMA group was significantly higher than in the Ti group (96 h). The expression of NFATc1 was found in BMMs in the presence of the wear particles and RANKL. In bone pit resorption assay, the wear particles significantly increased the resorption area and total number of resorption pits in BMMs-seeded ivory slices. Addition of 11R-VIVIT peptide (a specific inhibitor of calcineurin-mediated NFAT activation, 2.0 µmol/L) did not significantly affect the viability of BMMs, but abolished almost all the wear particle-induced alterations in BMMs. Furthermore, VIVIT reduced TNF-α production much more efficiently in the PMMA group than in the Ti group (96 h). CONCLUSION: Calcineurin/NFAT pathway mediates wear particles-induced TNF-α release and osteoclastogenesis from BMMs. Blockade of this signaling pathway with VIVIT may provide a promising therapeutic modality for the treatment of periprosthetic osteolysis.


Assuntos
Calcineurina/metabolismo , Fatores de Transcrição NFATC/metabolismo , Oligopeptídeos/farmacologia , Osteoclastos/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/genética , Osteoclastos/efeitos dos fármacos , Polimetil Metacrilato/farmacologia , Ligante RANK/administração & dosagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Titânio/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(11): 3040-3, 2012 Nov.
Artigo em Zh | MEDLINE | ID: mdl-23387175

RESUMO

The present paper reports a double pass forward superfluorescent fiber source (SFS), which uses a length of large mode area double cladding ytterbium doped fiber as gain medium. The maximum output power of this SFS is 341 mW. With the output power between 201 and 341 mW, the 3dB bandwidth of this SFS was more than 80 nm. This is the widest 3 dB bandwidth obtained from ytterbium doped SFS. The output power of the SFS linearly increased with the increment of the pump source injected current. It's output power is not very high, but under normal circumstances, it could meet the needs of the SFS. From the energy level structure of ytterbium ions and the absorption cross-section/emission cross section of ytterbium ions in quartz substrate, the physical mechanisms responsible for superfluorescence were analyzed. This double-cladding ytterbium-doped superfluorescent fiber laser benefits from the superfluorescence radiation near 1 025 and 1 075 nm, so the superfluorescence with 3 dB bandwidth reaching up to 80 nm could be obtained.

13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1483, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754852

RESUMO

In the title mol-ecule, C(30)H(32)N(2)O(2), the two tolyl rings form dihedral angles of 65.8 (1) and 6.6 (1)° with the isoindole-1,3-dione mean plane. The cyclo-hexane ring adopts a chair conformation.

14.
Int J Mol Med ; 47(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33693956

RESUMO

Insulin resistance (IR) is defined as impaired insulin function, reduced glucose uptake and increased glucose production, which can result in type II diabetes, metabolic syndrome and even bone metabolic disorders. A possible reason for the increasing incidence of IR is population aging. Adipose tissue (AT) is an important endocrine organ that serves a crucial role in whole­body energy homeostasis. AT can be divided into white AT (WAT), beige AT and brown AT (BAT). Several mechanisms have been previously associated with age­dependent IR in WAT. However, BAT, a metabolically active tissue, controls the levels of plasma glucose and triglyceride metabolism. Therefore, the present review aimed to summarize the mechanisms of age­dependent IR induced by AT and to determine the role of WAT browning in achieving positive therapeutic outcomes in age­dependent IR.


Assuntos
Tecido Adiposo Marrom/metabolismo , Envelhecimento/metabolismo , Metabolismo Energético , Resistência à Insulina , Tecido Adiposo Branco , Animais , Humanos
15.
Cell Death Dis ; 12(2): 164, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558476

RESUMO

In this study, we identified the multifaceted effects of atezolizumab, a specific monoclonal antibody against PD-L1, in tumor suppression except for restoring antitumor immunity, and investigated the promising ways to improve its efficacy. Atezolizumab could inhibit the proliferation and induce immune-independent apoptosis of osteosarcoma cells. With further exploration, we found that atezolizumab could impair mitochondria of osteosarcoma cells, resulting in increased release of reactive oxygen species and cytochrome-c, eventually leading to mitochondrial-related apoptosis via activating JNK pathway. Nevertheless, the excessive release of reactive oxygen species also activated the protective autophagy of osteosarcoma cells. Therefore, when we combined atezolizumab with autophagy inhibitors, the cytotoxic effect of atezolizumab on osteosarcoma cells was significantly enhanced in vitro. Further in vivo experiments also confirmed that atezolizumab combined with chloroquine achieved the most significant antitumor effect. Taken together, our study indicates that atezolizumab can induce mitochondrial-related apoptosis and protective autophagy independently of the immune system, and targeting autophagy is a promising combinatorial approach to amplify its cytotoxicity.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Antígeno B7-H1/antagonistas & inibidores , Neoplasias Ósseas/tratamento farmacológico , Cloroquina/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Mitocôndrias/efeitos dos fármacos , Osteossarcoma/tratamento farmacológico , Animais , Antígeno B7-H1/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Camundongos SCID , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Nat Commun ; 12(1): 1706, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731712

RESUMO

Our incomplete understanding of osteoarthritis (OA) pathogenesis has significantly hindered the development of disease-modifying therapy. The functional relationship between subchondral bone (SB) and articular cartilage (AC) is unclear. Here, we found that the changes of SB architecture altered the distribution of mechanical stress on AC. Importantly, the latter is well aligned with the pattern of transforming growth factor beta (TGFß) activity in AC, which is essential in the regulation of AC homeostasis. Specifically, TGFß activity is concentrated in the areas of AC with high mechanical stress. A high level of TGFß disrupts the cartilage homeostasis and impairs the metabolic activity of chondrocytes. Mechanical stress stimulates talin-centered cytoskeletal reorganization and the consequent increase of cell contractile forces and cell stiffness of chondrocytes, which triggers αV integrin-mediated TGFß activation. Knockout of αV integrin in chondrocytes reversed the alteration of TGFß activation and subsequent metabolic abnormalities in AC and attenuated cartilage degeneration in an OA mouse model. Thus, SB structure determines the patterns of mechanical stress and the configuration of TGFß activation in AC, which subsequently regulates chondrocyte metabolism and AC homeostasis.


Assuntos
Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Estresse Mecânico , Fator de Crescimento Transformador beta/metabolismo , Animais , Osso e Ossos/patologia , Linhagem Celular , Condrócitos/metabolismo , Citoesqueleto/metabolismo , Homeostase , Humanos , Integrina alfaV/genética , Integrina alfaV/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteoartrite/metabolismo , Osteoartrite/patologia , Transdução de Sinais , Talina/metabolismo
17.
Ann Transl Med ; 8(15): 932, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32953732

RESUMO

BACKGROUND: Currently, the perioperative care of fracture patients is compromised due to the outbreak of COVID-19 in China and the world. This study aims to assess the clinical features of fracture patients at our hospital during the COVID-19 outbreak and formulate the medical steps to ensure the effective treatment of fracture patients with minimal risk of infection to healthcare workers. METHODS: One hundred twelve patients with different fractures that were admitted to the orthopedics department of our hospital from January 24 to March 9 in 2020 were reviewed. Data including age, gender, injury location, admission time, operation time, discharge time were compared with fracture patients from the same period in 2019. RESULTS: Compared to the same period in 2019, there is a 42% decrease in the number of fracture patients in 2020. Specifically, the incidences of forearm, thigh, hand, and foot fractures have increased during the COVID-19 outbreak, while other parts are less affected. The time from injury to hospitalization, the surgery wait time and time of discharge after surgery for patients with hip fractures were 2.9±7.1, 2.0±1.7 and 7.7±4.0 days respectively in 2019, which changed to 2.0±5.0, 4.5±4.0 and 10.6±4.2 days in 2020. Following the orthopedic treatment regimen followed at our hospital, all patients had non-life-threatening limb fractures. Six patients were operated in a negative pressure room, and emergency screening was completed for six patients. No patients were positive for COVID-19, and all were discharged safely without infection or other serious complications. CONCLUSIONS: Hip fractures are highly prevalent during this epidemic. However, mandatory screening delays surgery by more than 48 hours. The orthopedic department should prioritize screening of emergency patients to minimize the risk of infection among other patients and medical personnel.

18.
Aging (Albany NY) ; 12(2): 1213-1236, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31981455

RESUMO

In this study, we identified microRNAs that regulate the expression of programmed death-ligand 1(PD-L1) in osteosarcoma and investigated their role in PD-L1-targeted immunotherapy. MicroRNA sequencing analysis showed that the expression of PD-L1 is regulated by microRNA-200a in U2OS, 143B, and K7 osteosarcoma cells. MicroRNA-200a overexpression induced the upregulation of PD-L1 in the osteosarcoma cells. CD8+ T cells co-cultured with microRNA-200a-overexpressing osteosarcoma cells showed reduced survival, proliferation, and secretion of granzyme B and perforin. The same phenomenon was also observed in the K7-derived syngeneic mouse model, as microRNA-200a promoted tumor growth by increasing the percentage of Foxp3+ regulatory T lymphocytes while reducing the proportions of CD4+, CD8+, and IFN-γ+ cytotoxic T lymphocytes. But microRNA-200a overexpression group was also more responsive to PD-L1-targeted immunotherapy than the controls. In addition, the tumor tissues from 32 osteosarcoma patients showed that high expression of microRNA-200a and PD-L1 was associated with poor tumor necrosis rate after chemotherapy. Moreover, we confirmed that tensin homolog deleted on chromosome ten (PTEN) could act as the target gene for microRNA-200a during the upregulation of PD-L1. Thus, our findings provide important and novel insight into a regulatory axis involving microRNA-200a/PTEN/ PD-L1 axis, which determines osteosarcoma growth and the efficacy of PD-L1-targeted immunotherapy.


Assuntos
Antígeno B7-H1/genética , Doxorrubicina/farmacologia , Regulação Neoplásica da Expressão Gênica , Imunomodulação , MicroRNAs/genética , Osteossarcoma/etiologia , Osteossarcoma/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Criança , Feminino , Humanos , Imuno-Histoquímica , Imunomodulação/genética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Receptor de Morte Celular Programada 1/metabolismo , Interferência de RNA , Transdução de Sinais , Adulto Jovem
19.
J Diabetes Res ; 2020: 6047145, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32064276

RESUMO

BACKGROUND: More and more studies focus on the relationship between the gastrointestinal microbiome and type 2 diabetes, but few of them have actually explored the relationship between enterotypes and type 2 diabetes. Materials and Methods. We enrolled 134 patients with type 2 diabetes and 37 nondiabetic controls. The anthropometric and clinical indices of each subject were measured. Fecal samples of each subject were also collected and were processed for 16S rDNA sequencing. Multiple logistic regression analysis was used to determine the associations of enterotypes with type 2 diabetes. Multiple linear regression analysis was used to explore the relationship between lipopolysaccharide levels and insulin sensitivity after adjusting for age, BMI, TG, HDL-C, DAO, and TNF-α. The correlation analysis between factors and microbiota was identified using Spearman correlation analysis. The correlation analysis between factors was identified using partial correlation analysis. RESULTS: Gut microbiota in type 2 diabetes group exhibited lower bacterial diversity compared with nondiabetic controls. The fecal communities from all subjects clustered into two enterotypes distinguished by the levels of Bacteroides and Prevotella. Logistic regression analysis showed that the Bacteroides and Bacteroides and Prevotella enterotype. Partial correlation analysis showed that lipopolysaccharide was closely associated with diamine oxidase, tumor necrosis factor-alpha, and Gutt insulin sensitivity index after adjusting for multiple covariates. Furthermore, the level of lipopolysaccharide was found to be an independent risk factor for insulin sensitivity. CONCLUSIONS: We identified two enterotypes, Bacteroides and Prevotella, among all subjects. Our results showed that the Bacteroides enterotype was an independent risk factor for type 2 diabetes, which was due to increased levels of lipopolysaccharide causing decreased insulin sensitivity.Bacteroides and Prevotella enterotype. Partial correlation analysis showed that lipopolysaccharide was closely associated with diamine oxidase, tumor necrosis factor-alpha, and Gutt insulin sensitivity index after adjusting for multiple covariates. Furthermore, the level of lipopolysaccharide was found to be an independent risk factor for insulin sensitivity. Bacteroides and.


Assuntos
Bacteroides , Diabetes Mellitus Tipo 2/microbiologia , Microbioma Gastrointestinal/fisiologia , Prevotella , Actinobacteria , Idoso , Amina Oxidase (contendo Cobre)/sangue , Bacteroidetes , Biodiversidade , Glicemia/metabolismo , Peptídeo C/sangue , Estudos de Casos e Controles , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Firmicutes , Fusobactérias , Microbioma Gastrointestinal/genética , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Resistência à Insulina , Lipopolissacarídeos/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Prandial , Proteobactérias , RNA Ribossômico 16S/genética , Fatores de Risco , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue , Verrucomicrobia
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