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1.
Small ; 19(9): e2205053, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36526434

RESUMO

Monolayer molybdenum disulfide (MoS2 ) nanoenzymes exhibit a piezoelectric polarization, which generates reactive oxygen species to inactivate tumors under ultrasonic strain. However, its therapeutic efficiency is far away from satisfactory, due to stackable MoS2 , quenching of piezo-generated charges, and monotherapy. Herein, chitosan-exfoliated monolayer MoS2 (Ch-MS) is composited with atomic-thin MXene, Ti3 C2 (TC), to self-assemble a multimodal nanoplatform, Ti3 C2 -Chitosan-MoS2 (TC@Ch-MS), for tumor inactivation. TC@Ch-MS not only inherits piezoelectricity from monolayer MoS2 , but also maintains remarkable stability. Intrinsic metallic MXene combines with MoS2 to construct an interfacial Schottky heterojunction, facilitating the separation of electron-hole pairs and endowing TC@Ch-MS increase-sensitivity magnetic resonance imaging responding. Schottky interface also leads to peroxidase mimetics with excellent catalytic performance toward H2 O2 in the tumor microenvironment under mechanical vibration. TC@Ch-MS possesses the superior photothermal conversion efficiency than pristine TC under near-infrared ray illumination, attributed to its enhanced interlaminar conductivity. Meanwhile, TC@Ch-MS realizes optimized efficiency on tumor apoptosis with immunotherapy. Therefore, TC@Ch-MS achieves an integrated diagnosis and multimodal treatment nanoplatform, whereas the toxicity to normal tissue cells is negligible. This work may shed fresh light on optimizing the piezoelectric materials in biological applications, and also give prominence to the significance of intrinsic metallicity in MXene.


Assuntos
Quitosana , Neoplasias , Humanos , Molibdênio , Neoplasias/terapia , Microambiente Tumoral
2.
Artigo em Inglês | MEDLINE | ID: mdl-35990834

RESUMO

Exosomes derived from human bone marrow mesenchymal stem cells (BMSCs) play potential protective roles in asthma. However, the underlying mechanisms remain not fully elucidated. Herein, exosomes were isolated from BMSCs, and the morphology, particle size, and exosome marker proteins were identified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blot, respectively. Then airway smooth muscle cells (ASMCs) were treated with transforming growth factor-ß1 (TGF-ß1) to construct a proliferation model and then incubated with BMSCs-derived exosomes. We found that exosome incubation increased miR-221-3p expression and inhibited proliferation, migration, and the levels of extracellular matrix (ECM) proteins including fibronectin and collagen III. Moreover, FGF2 was identified as a target gene of miR-221-3p. FGF2 overexpression reversed the inhibitory effects of exosomal miR-221-3p on ASMC progression. Besides, the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) is inhibited by exosomal miR-221-3p, which was reversed by FGF2 overexpression. And ERK1/2 signaling activator reversed the effects of exosomal miR-221-3p on ASMC progression. Additionally, an ovalbumin (OVA)-induced asthmatic mice model was established, and exosome treatment alleviated airway hyper-responsiveness (AHR), histopathological damage, and ECM deposition in asthmatic mice. Taken together, our findings indicated that exosomal miR-221-3p derived from BMSCs inhibited FGF2 expression and the ERK1/2 signaling, thus attenuating proliferation, migration, and ECM deposition in ASMCs and alleviating asthma progression in OVA-induced asthmatic mice. Our findings may provide a novel therapeutic strategy for asthma.

3.
Proteomics ; 22(1-2): e2100094, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34564948

RESUMO

Although tyrosine kinase inhibitors (TKIs), including imatinib, have greatly improved clinical treatment of patients with chronic myeloid leukemia (CML), drug resistance remains a major obstacle. Studies on the mechanisms underlying imatinib resistance and other alternative drugs are urgently needed. Liquid chromatography tandem mass spectrometry was applied to investigate the differences in proteomics and phosphoproteomics between K562 and K562/G (imatinib resistant K562). Multiple bioinformatics analyses were performed to unveil the differential signal pathways. CCK-8 was used to detect cell proliferation. Flow cytometry was performed to analyze reactive oxygen species (ROS), cell cycle, and cell apoptosis. Western blotting and quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) were used to observe the changes of ROS and autophagy associated with imatinib resistance in CML. Our results indicated that ROS-autophagy formed one negative feedback loop and was associated with imatinib resistance. Additionally, the limited-rate enzymes of serine synthesis pathway were escalated in K562/G, which could contribute to the increased cyclin-dependent kinases and cell proliferation index. According to phosphoproteomics data, K562/G cells exhibited abnormal phosphorylation of splicing signals. These results revealed that it could be one useful strategy to correct metabolism shift and oxidative stress, or moderately regulate autophagy. Future research should focus on the discovery of potential targets in ROS-autophagy loop.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Autofagia , Resistencia a Medicamentos Antineoplásicos , Humanos , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteômica , Espécies Reativas de Oxigênio
4.
Chem Biol Drug Des ; 98(1): 114-126, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33961336

RESUMO

3-O-trans-caffeoyloleanolic acid (COA) is a pentacyclic triterpenoid compound, with significant anti-inflammatory effects. In this study, we report the protective effects of COA on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and explored its mechanism of action. LPS was used to construct in vivo mouse ALI models to observe the effects of COA pretreatment on lung pathology, inflammation, and oxidative stress. In vitro, mouse alveolar macrophages MH-S cells were cultured and stimulated with LPS to investigate the effects of COA pretreatment on inflammation and oxidative stress. Western blotting was used to investigate the expression of iNOS, TLR4, p-p65, p-AKT, and p-PI3K from in vivo and in vitro samples. The results showed that COA significantly improved lung injury, inhibited neutrophil infiltration, prevented macrophage infiltration, inhibited the release of inflammatory factors, reduced oxidative stress, and down-regulated the expression of iNOS, TLR4, p-p65, p-AKT, and p-PI3K in ALI mice caused by LPS. In vitro, COA inhibited the release of inflammatory factors, reduced oxidative stress, and down-regulated the expression of iNOS, TLR4, p-p65, p-AKT, and p-PI3K in MH-S cells stimulated with LPS. Of interest, the protective effects of COA were significantly attenuated in MH-S cells pretreated with the PI3K phosphopeptide activator 740Y-P with no effect on TLR4 expression observed. Taken together, these findings confirm the protective effects of COA on ALI. We further demonstrate that the anti-inflammation and antioxidant effects of COA are mediated through its effects on PI3K/AKT and potentially TLR4.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/química , Ácido Oleanólico/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/metabolismo , Macrófagos/citologia , Masculino , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/metabolismo , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Fosfopeptídeos/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
5.
Mediators Inflamm ; 2020: 3645157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32148437

RESUMO

Myasthenia gravis (MG) is a CD4+ T cell-dependent autoimmune disease resulting from aberrant immune response mediated by circulating autoantibodies at the neuromuscular junction. Intravenous immunoglobulin (IVIg) is an expensive and commonly used immunotherapeutic approach to treat patients with MG. The mechanisms of actions involved in IVIg treatment, however, remain to be investigated. In an effort to examine the roles of various subsets of CD4+ T cells in the periphery blood of MG and uncover the mechanisms that contribute to the therapeutical effects of IVIg, we first demonstrated that a subset of CD4+ T cells, CTLA-4-expressing regulatory T (Treg) cells, were underrepresented and functionally defective in MG patients. The dynamic profiling during the IVIg therapy course further revealed an inverse relationship between the frequency of CTLA-4+ Treg and the quantitative MG (QMG) score that represents disease severity. Our mechanistic studies indicated that IVIg expands CTLA-4-Treg cells via modulating antigen-presenting dendritic cells (DCs). To determine the molecular defects of CTLA-4 in abnormities of Treg in MG patients, we demonstrated hypermethylation at -658 and -793 CpGs of CTLA-4 promoter in MG Tregs. Interestingly, IVIg therapy significantly reduced the methylation level at these two sites in MG patients. Overall, our study may suggest a role of CTLA-4 in functionally defected Treg cells in MG and its actions involved in IVIg therapy.


Assuntos
Antígeno CTLA-4/metabolismo , Miastenia Gravis/metabolismo , Linfócitos T Reguladores/metabolismo , Linfócitos T/metabolismo , Adulto , Linfócitos T CD4-Positivos/metabolismo , Células Dendríticas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imunoglobulinas Intravenosas , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/imunologia , Reação em Cadeia da Polimerase em Tempo Real
6.
Cell Immunol ; 348: 104041, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31983398

RESUMO

Chimeric antigen receptor (CAR)-modified T cell therapy evokes only modest antitumor responses in solid tumors. Meso-CAR-T cells are CAR-T cells targeted mesothelin, which are over-expressed in tumor tissues of breast cancer patients. To improve the therapeutic effects, we combined it with rAd.sT, a transforming growth factor ß signaling-targeted oncolytic adenovirus, to therapy breast cancer. In subcutaneous MDA-MB-231 xenograft of NSG mice, both rAd.sT and meso-CAR-T inhibited tumor growth, however combination therapy produced stronger inhibitory effects. Interestingly, rAd.sT reduced tumor burden at initial stage following vector treatments, while meso-CAR-T cells decreased tumor burden at a later stage. Moreover, meso-CAR-T could target tumor microenvironments, and combination therapy could enhance cytokines production, such as interleukin (IL)-6 and IL-12 in tumor microenvironment. In conclusion, combination of rAd.sT with meso-CAR-T produced much more impressive antitumor responses to breast cancer and its metastasis, which could be developed as a promising therapeutic strategy.


Assuntos
Neoplasias da Mama , Terapia Combinada/métodos , Imunoterapia Adotiva/métodos , Terapia Viral Oncolítica/métodos , Adenoviridae , Animais , Antineoplásicos/farmacologia , Feminino , Proteínas Ligadas por GPI/antagonistas & inibidores , Humanos , Mesotelina , Camundongos , Vírus Oncolíticos , Receptores de Antígenos Quiméricos , Fator de Crescimento Transformador beta/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Front Neurosci ; 13: 1388, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32009878

RESUMO

Delayed diagnosis of insulinoma remains an intractable clinical challenge because the symptoms are in most cases misattributed to other disorders. In this study, a 64-year-old man presented with intermittent seizure episodes after being misdiagnosed with epilepsy and receiving anti-epileptic drugs for 4 years. During this period, the patient continued to suffer from repeated seizures. A starvation test, pancreatic enhancement CT, MRI scan, and pathological examination clinically diagnosed insulinoma, and the symptoms improved following surgical removal of the tumor. The appearance of unusual manifestations and insulinoma imaging makes it difficult to accurately diagnose the condition. This case emphasizes the need for careful reassessment of all atypical and refractory seizures for neurologists.

8.
Leuk Lymphoma ; 60(7): 1709-1720, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30516071

RESUMO

MicroRNAs (miRNAs) are involved in various processes from the development to drug resistance of tumors, including chronic myeloid leukemia (CML). In this study, we examined the STAT5-related miRNA-expression profile in CML cell lines (K562 and imatinib-resistant K562/G) by quantitative real-time reverse-transcriptase polymerase chain reactions. MiR-221 expression was markedly decreased in K562/G cells and peripheral blood mononuclear cells from patients with treatment failure, when compared to imatinib-sensitive CML cells and patients with optimal responses respectively. We also observed the expression of STAT5 inversely correlated with miR-221 expression in K562 and KBM5 cells. Additionally, STAT5 was validated as a direct target of miR-221 in dual-luciferase reporter vector assays. MiR-221 restoration and STAT5 knockdown in K562/G cells increased the sensitivity of CML cells to imatinib by reducing the Bcl2: Bax ratio. Collectively, our data suggested that miR-221-STAT5 axis played crucial roles in controlling the sensitivity of CML cells to imatinib.


Assuntos
Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , MicroRNAs/genética , Fator de Transcrição STAT5/metabolismo , Adolescente , Adulto , Idoso , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Feminino , Seguimentos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Fator de Transcrição STAT5/genética , Células Tumorais Cultivadas , Adulto Jovem
9.
Mol Med Rep ; 19(3): 1965-1971, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30592270

RESUMO

Numerous studies have demonstrated that microRNAs (miRNAs) are upregulated or downregulated in retinoblastoma (RB), and that this phenomenon is associated with the modulation of various malignant behaviours during RB occurrence and development. Therefore, the mechanisms that associate deregulated miRNAs with RB initiation and progression must be understood to identify effective therapeutic techniques for patients with RB. In the present study, miR­492 expression was upregulated in RB tissues and cell lines. The effects of miR­492 inhibition on the proliferation and invasion of RB cells were examined using Cell Counting kit­8 and invasion assays. The results revealed that miR­492 downregulation significantly decreased the proliferation and invasion of RB cells. Bioinformatics analysis predicted that large tumour­suppressor kinase 2 (LATS2) was a putative target of miR­492. Luciferase reporter assay, reverse transcription­quantitative polymerase chain reaction and western blot analysis demonstrated that LATS2 was a direct target gene of miR­492 in RB cells. In addition, LATS2 expression was downregulated in RB tissues, and its downregulation was inversely correlated with miR­492 level. Furthermore, LATS2­knockdown abrogated the effects of miR­492 downregulation in RB cells. In conclusion, miR­492 inhibition may impede the malignant behaviour of RB by directly targeting LATS2. Therefore, targeting this miRNA may be an effective therapeutic method for treating patients with RB.


Assuntos
Proliferação de Células/genética , MicroRNAs/genética , Proteínas Serina-Treonina Quinases/genética , Retinoblastoma/genética , Proteínas Supressoras de Tumor/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , MicroRNAs/antagonistas & inibidores , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Retinoblastoma/patologia , Transdução de Sinais/genética , Proteínas Supressoras de Tumor/antagonistas & inibidores
10.
Cell Immunol ; 331: 49-58, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29935762

RESUMO

Identifying targets for chimeric antigen receptor-modulated T lymphocyte (CAR-T) therapy against solid tumors is an urgent problem to solve. In this study, we showed for the first time that the receptor tyrosine kinase, AXL, is overexpressed in various tumor cell lines and patient tumor tissues including triple negative breast cancer (TNBC) cell lines and patient samples, making AXL a potent novel target for cancer therapy, specifically for TNBC treatment. We also engineered T cells with a CAR consisting of a novel single-chain variable fragment against AXL and revealed its antigen-specific cytotoxicity and ability to release cytokines in a TNBC cell line and other AXL-positive tumors in vitro. Furthermore, AXL-CAR-T cells displayed a significant anti-tumor effect and in vivo persistence in a TNBC xenograft model. Taken together, our findings indicate that AXL-CAR-T cells can represent a promising therapeutic strategy against TNBC.


Assuntos
Imunoterapia Adotiva/métodos , Proteínas Proto-Oncogênicas/imunologia , Receptores Proteína Tirosina Quinases/imunologia , Receptores de Antígenos Quiméricos/imunologia , Neoplasias de Mama Triplo Negativas/terapia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Humanos , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Neoplasias de Mama Triplo Negativas/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Tirosina Quinase Axl
11.
Medicine (Baltimore) ; 97(19): e0696, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29742721

RESUMO

RATIONALE: Autoimmune encephalitis and Lambert-Eaton myasthenic syndrome are classic paraneoplastic neurological conditions common in patients with small cell lung cancer. PATIENT CONCERNS: The patient complained of tiredness, fluctuating recent memory loss, and inability to find his home. His family members reported a change in character, irritability, and paranoia. One month later, the patient had 1 grand mal seizure lasting 5 minutes. DIAGNOSIS: The patient was diagnosed with limbic encephalitis combined with Lambert-Eaton myasthenic syndrome. The gamma-aminobutyric acid B (GABAB) receptor and collapsin response mediator protein 5 (CRMP5, also called CV2) antibody test results were positive. Nine months after the onset of symptoms, the patient was diagnosed with small cell lung cancer. INTERVENTIONS: The patient was administered intravenous immunoglobulin for 5 days. He was then treated with 60 mg prednisone once per day. The prednisone dose was gradually reduced by 1 tablet every 2 weeks. After the diagnosis, the patient underwent 6 courses of chemotherapy with cisplatin combined with sequential chemoradiation therapy. OUTCOMES: The patient was able to take care of himself. Neurological examination revealed a lower limb proximal muscle strength level of 4 and a reduced limb tendon reflex. The patient had deficits in short-term memory, a Mini-Mental State Examination score of 26, Montreal Cognitive Assessment score of 24, Self-rating Depression Scale score of 54 (mild depression), and Self-Rating Anxiety Scale score of 42 (normal). LESSONS: Autoimmune diseases of the peripheral and central nervous systems can be observed at the same time in patients with small cell lung cancer, even when magnetic resonance imaging findings are negative and immune therapy is effective.


Assuntos
Anticorpos/sangue , Encefalite/complicações , Doença de Hashimoto/complicações , Síndrome Miastênica de Lambert-Eaton/complicações , Neoplasias Pulmonares/complicações , Proteínas do Tecido Nervoso/imunologia , Receptores de GABA-B/imunologia , Carcinoma de Pequenas Células do Pulmão/complicações , Anti-Inflamatórios/uso terapêutico , Encefalite/tratamento farmacológico , Encefalite/imunologia , Doença de Hashimoto/tratamento farmacológico , Doença de Hashimoto/imunologia , Humanos , Hidrolases , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Síndrome Miastênica de Lambert-Eaton/tratamento farmacológico , Síndrome Miastênica de Lambert-Eaton/imunologia , Neoplasias Pulmonares/terapia , Masculino , Proteínas Associadas aos Microtúbulos , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/terapia
12.
Exp Ther Med ; 15(2): 1403-1409, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29434724

RESUMO

High expression of the Wilms' tumor gene (WT1) in acute myeloid leukemia (AML) has been considered as a sensitive marker of minimal residual disease (MRD). The present study investigated the significance of quantitative analysis of WT1 mRNA, combined with multiparameter flow cytometry (MFC) regarding its efficacy and prognostic as well as relapse prediction value for leukemia patients with hematopoietic stem cell transplantation. Reverse-transcription quantitative polymerase chain reaction analysis demonstrated that the expression of WT1 in the initial and relapse group was significant higher than that in the complete remission (CR) group (P<0.01). WT1 and the donor chimerism were negatively correlated (r=-0.73, P<0.05). In all AML patients, WT1 was the highest in the M3 subtype and the lowest in the M1 subtype. Follow-up of 12 AML patients demonstrated that WT1 gene expression levels markedly decreased after CR, but obviously increased after relapse, as did the rate of the leukemia cells detected by MFC. The combined usage of MFC and WT1 monitoring contributed to an improved detection rate of relapse (91.7%), and may be used to monitor MRD, assess the treatment efficacy and prognosis, and predict the risk of recurrence in leukemia patients without specific molecular markers after allogeneic hematopoietic stem cell transplantation.

13.
Int J Mol Med ; 41(1): 455-463, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29115375

RESUMO

The persistent activation of signal transducer and activator of transcription 5 (STAT5) may principally be attributed to breakpoint cluster region (BCR)-Abelson murine leukemia viral oncogene homolog 1 (ABL1), and have multi-faceted effects in the development of chronic myeloid leukemia (CML). The p53 protein network regulates important mechanisms in DNA damage repair, cell cycle regulation/checkpoints, and cell senescence and apoptosis, as demonstrated by its ability to positively regulate the expression of various pro-apoptotic genes, including B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax). In the present study, it was observed that the mRNA levels of STAT5A and STAT5B were upregulated in patients with imatinib-resistant CML and in the imatinib-resistant K562/G CML cell line. In addition, increased expression of STAT5 was observed in the BCR-ABL1 mutation group, compared with that in the non-BCR-ABL1 mutation group, regardless of patient imatinib resistance state. Elevated levels of reactive oxygen species (ROS) and DNA double-strand breaks were identified in K562/G cells using flow cytometric and phosphorylated H2AX (γ-H2AX) foci immunofluorescence assays, respectively, compared with the imatinib-sensitive K562 cells. The levels of intracellular ROS and γ-H2AX were decreased by the ROS scavenger (N-acetylcysteine), and ROS levels were also markedly reduced by STAT5 inhibitor (SH-4-54). In addition, imatinib significantly inhibited the proliferation of K562 and K562/G cells, with half maximal inhibitory concentration values of 0.17±0.07 and 14.78±0.43 µM, respectively, and the levels of apoptosis were significantly different between K562 and K562/G cells following treatment with imatinib. The mRNA and protein levels of STAT5 and mouse double minute 2 homolog (MDM2) were upregulated, whereas those of Bax were downregulated in K562/G cells, as determined using western blot analysis. Additionally, although the two cell lines exhibited relatively low protein expression levels of p53, lower levels of p53 and TPp53BP1 transcripts were detected in the K562/G cells. Taken together, these findings suggest that the resistance of CML to the tyrosine kinase inhibitor, imatinib, may be associated with persistent STAT5-mediated ROS production, and the abnormality of the p53 pathway.


Assuntos
Mesilato de Imatinib/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Fator de Transcrição STAT5/genética , Proteína Supressora de Tumor p53/genética , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes abl/genética , Histonas/genética , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas Proto-Oncogênicas c-mdm2/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética
14.
Oncotarget ; 8(34): 57024-57038, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28915651

RESUMO

Natural killer (NK) cells are important innate immune cells that can directly kill transformed or virus-infected cells. The adoptive transfer of NK cells has been used to treat hematological malignancies; however, the limited sources and quantities of NK cells have restricted their clinical application. Here, we acquired sufficient quantities of functional NK cells from CD34+ cells treated with a cytokine cocktail. Microarray analysis of the cultured cells revealed a two-stage pattern of programmed differentiation during NK cell development. Different transcription factors were enriched during these two stages, suggesting that preparation of progenitors committed to the NK cell lineage occurs in program 1, while NK cell transformation and maturation occur in program 2. Cultured NK cells highly expressed signaling lymphocytic activation molecule (SLAM) family receptors (SFRs), while leukemia cells expressed SFR ligands. The engagement of these SFRs strengthened the cytotoxicity of NK cells toward leukemia cells. These results demonstrate a simple method of obtaining sufficient NK cells for clinical application, and have categorized NK cell differentiation according to commitment and transformation programs. Moreover, the binding between SFRs on NK cells and their ligands on leukemia cells suggests a new basis for NK cell therapy for treatment of leukemia.

15.
Cancer Res ; 77(2): 482-493, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27697766

RESUMO

The lack of effective tumor-associated antigens restricts the development of targeted therapies against myeloid leukemia. In this study, we compared gene expression patterns of acute myeloid leukemia (AML) and normal bone marrow samples and found that epithelial cell adhesion molecule (EpCAM) is frequently overexpressed in patients with AML, with EpCAM+ leukemic cells exhibiting enhanced chemoresistance and oncogenesis. The chemotherapeutic resistance of EpCAM-positive leukemic cells is a consequence of increased WNT5B signaling. Furthermore, we generated EpCAM antibodies that enabled phagocytosis or cytotoxicity of AML cells by macrophage or natural killer cells, respectively. Finally, EpCAM antibody treatment depleted AML in subcutaneous, disseminated, and intramedullary engrafted mice. In summary, EpCAM exhibits promise as a novel target for the treatment of leukemia. Cancer Res; 77(2); 482-93. ©2016 AACR.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Molécula de Adesão da Célula Epitelial/antagonistas & inibidores , Vigilância Imunológica/efeitos dos fármacos , Leucemia Mieloide Aguda/patologia , Animais , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Leucemia Mieloide Aguda/imunologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Biol Chem ; 289(18): 12578-92, 2014 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-24648522

RESUMO

The obligate intracellular parasite Toxoplasma gondii secretes effector molecules into the host cell to modulate host immunity. Previous studies have shown that T. gondii could interfere with host NF-κB signaling to promote their survival, but the effectors of type I strains remain unclear. The polymorphic rhoptry protein ROP18 is a key serine/threonine kinase that phosphorylates host proteins to modulate acute virulence. Our data demonstrated that the N-terminal portion of ROP18 is associated with the dimerization domain of p65. ROP18 phosphorylates p65 at Ser-468 and targets this protein to the ubiquitin-dependent degradation pathway. The kinase activity of ROP18 is required for p65 degradation and suppresses NF-κB activation. Consistently, compared with wild-type ROP18 strain, ROP18 kinase-deficient type I parasites displayed a severe inability to inhibit NF-κB, culminating in the enhanced production of IL-6, IL-12, and TNF-α in infected macrophages. In addition, studies have shown that transgenic parasites carrying kinase-deficient ROP18 induce M1-biased activation. These results demonstrate for the first time that the virulence factor ROP18 in T. gondii type I strains is responsible for inhibiting the host NF-κB pathway and for suppressing proinflammatory cytokine expression, thus providing a survival advantage to the infectious agent.


Assuntos
NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Protozoários/metabolismo , Transdução de Sinais , Toxoplasma/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Western Blotting , Linhagem Celular , Feminino , Células HEK293 , Interações Hospedeiro-Parasita , Humanos , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Proteólise , Proteínas de Protozoários/genética , Serina/metabolismo , Toxoplasma/genética , Toxoplasma/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
17.
Cell Signal ; 26(6): 1204-12, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24583285

RESUMO

In order to accomplish their life cycles, intracellular pathogens, including the apicomplexan Toxoplasma gondii, subvert the innate apoptotic response of infected host cells. However, the precise mechanisms of parasite interference with the apoptotic pathway remain unclear. MicroRNAs (miRNAs) regulate gene expression at the posttranscriptional level. Using T. gondii strain TgCtwh3, which was isolated from felids and possesses the predominant genotype China 1 (ToxoDB(#)9) in China, we analyzed the miRNA expression profile of human macrophages challenged with TgCtwh3. The results showed that miR-17-92 miRNA expression was significantly increased and Bim was decreased in TgCtwh3-infected cells. Database analysis of miR-17-92 miRNAs revealed the potential binding sites in the 3'UTR of Bim, one of the crucial effectors of pro-apoptosis. Furthermore, we demonstrated that the promoter of the miR-17-92 gene cluster which encodes miRNAs was transactivated through the promoter binding of the STAT3 following TgCtwh3 infection. Taken together, we describe a novel STAT3-miR-17-92-Bim pathway, thus providing a mechanistic explanation for inhibition of apoptosis of host cells following Toxoplasma infection.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Macrófagos/parasitologia , Proteínas de Membrana/metabolismo , MicroRNAs/genética , Proteínas Proto-Oncogênicas/metabolismo , Fator de Transcrição STAT3/metabolismo , Toxoplasma/fisiologia , Adulto , Sequência de Aminoácidos , Animais , Proteína 11 Semelhante a Bcl-2 , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Parasita , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Dados de Sequência Molecular , Família Multigênica , RNA Longo não Codificante , Adulto Jovem
18.
Parasitol Res ; 112(8): 3019-27, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23722717

RESUMO

Toxoplasma gondii is an apicomplexan parasite capable of transplacental transmission to cause spontaneous abortion or significant disease in the surviving neonate. Different from the dominant genotypes of T. gondii strains in European and North American which belong to three distinct clonal lineages, type I, type II, and type III, isolates from China possess the predominant genotype of China 1(ToxoDB#9) with a different virulence. The genotype-associated pathogenesis has been investigated previously. Based on two isolates of T. gondii from Chinese wild cats, a murine model of pregnancy and one transwell system in vitro, here we reported differentially polarized activation of macrophages induced by genotype China 1 strains, TgCtwh3 and TgCtwh6 with different virulence to mice, and its impact on trophoblast apoptosis. The results showed that macrophages were alternatively activated when infected with virulent TgCtwh3 while classically activated when infected with low virulent (cyst-forming) TgCtwh6 both in vitro and in vivo. By the analysis of flow cytometry, the percentage of the Th1 cells in two infection groups decreased significantly, and the Th2 cells from spleen escalated only in the virulent TgCtwh3 group. Interestingly, the high parasite burden was noted in the placenta of TgCtwh3-infected group whereas the inflammatory cells infiltration predominates in the TgCtwh6-infected group. In vivo trophoblast apoptosis in TgCtwh3 group was found to be more obvious when compared with TgCtwh6 although it was present in both. The present observations indicate that polarization of macrophages and modulation of Th subsets induced by the isolates with identical genotype but different virulence could contribute to trophoblast apoptosis through different mechanisms, suggesting a virulence-associated pathogenesis of T. gondii in abnormal pregnant outcome.


Assuntos
Macrófagos/fisiologia , Toxoplasma/patogenicidade , Toxoplasmose Animal/parasitologia , Trofoblastos/fisiologia , Animais , Apoptose , Doenças do Gato/parasitologia , Gatos , China/epidemiologia , Técnicas de Cocultura , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos ICR , Placenta , Gravidez , Proteínas de Protozoários , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Virulência
19.
Inflammation ; 36(2): 337-45, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23065188

RESUMO

MicroRNA-155 (miR155) has been demonstrated as a central regulator of immune responses induced by inflammatory mediators. Previous studies suggest that miR155 may play adverse effects in various diseases. We hereby explored the roles of miR155 in the pathogenesis of Guillain-Barré syndrome (GBS). Peripheral blood mononuclear cells (PBMCs) were separated from GBS patients and healthy controls. Expression of miR155 in PBMCs was detected by quantitative PCR. An inhibitor of miR155 was transfected into the cultured PBMCs and the GBS-related cytokines were detected. Significantly, our study demonstrated that miR155 was downregulated in PBMCs from GBS patients and silencing of miR155 profoundly promoted the production of Th1-type cytokines in vitro. Our data effectively demonstrate a protective role of miR155 in GBS, which suggests that miR155 may be a promising target for the therapy of the disease.


Assuntos
Síndrome de Guillain-Barré/genética , Mediadores da Inflamação/metabolismo , Inflamação/genética , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , Adulto , Feminino , Humanos , Interferon gama/análise , Interleucina-12/análise , Interleucina-1beta/análise , Interleucina-4/análise , Leucócitos Mononucleares/citologia , Masculino , Interferência de RNA , RNA Interferente Pequeno , Fator de Necrose Tumoral alfa/análise
20.
Mol Med Rep ; 6(6): 1315-8, 2012 12.
Artigo em Inglês | MEDLINE | ID: mdl-22965224

RESUMO

The aim of this study was to determine the effects of VEGF treatment on focal cerebral ischemia in rats. Rats were administered PBS or VEGF at concentrations of 10, 20 or 30 µg/ml. The effects of VEGF on the rat infarct volume and neurological deficits were investigated. Transmission electron microscopy was used to observe the ultrastructure of the cerebral cortex. Treatments with VEGF reduced the infarct volume and improved neurological functions. VEGF increased microvessel generation and also inhibited apoptosis in the cerebral cortex and basal ganglia. For the rats in the 30 µg/ml VEGF group, an even higher number of proliferative endothelial cells were observed by electron microscopy. In conclusion, VEGF treatment has protective effects on focal cerebral ischemia in rats.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/patologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/ultraestrutura , Gânglios/efeitos dos fármacos , Imageamento por Ressonância Magnética , Masculino , Microscopia Eletrônica , Microvasos/efeitos dos fármacos , Radiografia , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/farmacologia
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