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1.
J Virol ; 92(6)2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29263275

RESUMO

Oncolytic virotherapy is an emerging treatment modality that uses replication-competent viruses to destroy cancer cells. M1 is a naturally occurring alphavirus (Togaviridae) which shows potent oncolytic activities against many cancers. Accumulation of unfolded proteins during virus replication leads to a transcriptional/translational response known as the unfolded protein response (UPR), which might counteract the antitumor effect of the oncolytic virus. In this report, we show that either pharmacological or biological inhibition of IRE1α or PERK, but not ATF6, substantially increases the oncolytic effects of the M1 virus. Moreover, inhibition of IRE1α blocks M1 virus-induced autophagy, which restricts the antitumor effects of the M1 virus through degradation of viral protein, in glioma cells. In addition, IRE1α suppression significantly increases the oncolytic effect of M1 virus in an orthotopic glioma model. From a molecular pathology study, we found that IRE1α is expressed at lower levels in higher-grade gliomas, suggesting greater antitumor efficacy of the oncolytic virus M1. Taken together, these findings illustrate a defensive mechanism of glioma cells against the oncolytic virus M1 and identify possible approaches to enhance the oncolytic viral protein accumulation and the subsequent lysis of tumor cells.IMPORTANCE Although oncolytic virotherapy is showing great promise in clinical applications, not all patients are benefiting. Identifying inhibitory signals in refractory cancer cells for each oncolytic virus would provide a good chance to increase the therapeutic effect. Here we describe that infection with the oncolytic virus M1 triggers the unfolded protein response (UPR) and subsequent autophagy, while blocking the UPR-autophagy axis significantly potentiates the antitumor efficacy of M1 in vitro and in vivo A survey of cancer tissue banks revealed that IRE1α, a key element in the UPR pathway, is commonly downregulated in higher-grade human gliomas, suggesting favorable prospects for the application of M1. Our work provides a potential predictor and target for enhancement of the therapeutic effectiveness of the M1 virus. We predict that the mechanism-based combination therapy will promote cancer virotherapy in the future.


Assuntos
Autofagia/imunologia , Endorribonucleases/deficiência , Glioma/terapia , Proteínas de Neoplasias/deficiência , Terapia Viral Oncolítica , Vírus Oncolíticos , Proteínas Serina-Treonina Quinases/deficiência , Togaviridae , Animais , Autofagia/genética , Linhagem Celular Tumoral , Chlorocebus aethiops , Cricetinae , Endorribonucleases/imunologia , Feminino , Glioma/genética , Glioma/imunologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Resposta a Proteínas não Dobradas/genética , Resposta a Proteínas não Dobradas/imunologia , Células Vero , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Neurochem ; 144(2): 186-200, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29205357

RESUMO

Hyperglycolysis, observed within the penumbra zone during brain ischemia, was shown to be detrimental for tissue survival because of lactate accumulation and reactive oxygen species overproduction in clinical and experimental settings. Recently, mounting evidence suggests that glycolytic reprogramming and induced metabolic enzymes can fuel the activation of peripheral immune cells. However, the possible roles and details regarding hyperglycolysis in neuroinflammation during ischemia are relatively poorly understood. Here, we investigated whether overactivated glycolysis could activate microglia and identified the crucial regulators of neuroinflammatory responses in vitro and in vivo. Using BV 2 and primary microglial cultures, we found hyperglycolysis and induction of the key glycolytic enzyme hexokinase 2 (HK2) were essential for microglia-mediated neuroinflammation under hypoxia. Mechanistically, HK2 up-regulation led to accumulated acetyl-coenzyme A, which accounted for the subsequent histone acetylation and transcriptional activation of interleukin (IL)-1ß. The inhibition and selective knockdown of HK2 in vivo significantly protected against ischemic brain injury by suppressing microglial activation and IL-1ß production in male Sprague-Dawley rats subjected to transient middle cerebral artery occlusion (MCAo) surgery. We provide novel insights for HK2 specifically serving as a neuroinflammatory determinant, thus explaining the neurotoxic effect of hyperglycolysis and indicating the possibility of selectively targeting HK2 as a therapeutic strategy in acute ischemic stroke.


Assuntos
Isquemia Encefálica/enzimologia , Isquemia Encefálica/genética , Glicólise/genética , Hexoquinase/genética , Hexoquinase/metabolismo , Ativação de Macrófagos/genética , Microglia/enzimologia , Acidente Vascular Cerebral/enzimologia , Acidente Vascular Cerebral/genética , Acetilcoenzima A/metabolismo , Acetilação , Animais , Indução Enzimática/genética , Hexoquinase/biossíntese , Histonas/metabolismo , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Inflamação/genética , Interleucina-1beta/metabolismo , Masculino , Interferência de RNA , Ratos , Ratos Sprague-Dawley
3.
Mol Ther ; 24(1): 156-65, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26373347

RESUMO

Oncolytic virotherapy is a novel and emerging treatment modality that uses replication-competent viruses to destroy cancer cells. Although diverse cancer cell types are sensitive to oncolytic viruses, one of the major challenges of oncolytic virotherapy is that the sensitivity to oncolysis ranges among different cancer cell types. Furthermore, the underlying mechanism of action is not fully understood. Here, we report that activation of cyclic adenosine monophosphate (cAMP) signaling significantly sensitizes refractory cancer cells to alphavirus M1 in vitro, in vivo, and ex vivo. We find that activation of the cAMP signaling pathway inhibits M1-induced expression of antiviral factors in refractory cancer cells, leading to prolonged and severe endoplasmic reticulum (ER) stress, and cell apoptosis. We also demonstrate that M1-mediated oncolysis, which is enhanced by cAMP signaling, involves the factor, exchange protein directly activated by cAMP 1 (Epac1), but not the classical cAMP-dependent protein kinase A (PKA). Taken together, cAMP/Epac1 signaling pathway activation inhibits antiviral factors and improves responsiveness of refractory cancer cells to M1-mediated virotherapy.


Assuntos
Alphavirus/genética , Colforsina/administração & dosagem , AMP Cíclico/metabolismo , Neoplasias/terapia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose , Linhagem Celular Tumoral , Colforsina/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fatores de Troca do Nucleotídeo Guanina/genética , Células HCT116 , Humanos , Camundongos , Neoplasias/genética , Terapia Viral Oncolítica , Vírus Oncolíticos/genética
4.
Cell Rep Med ; 4(10): 101229, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37820722

RESUMO

Although promising, dendritic cell (DC) vaccines still provide limited clinical benefits, mainly due to the immunosuppressive tumor microenvironment (TME) and the lack of tumor-associated antigens (TAAs). Oncolytic virus therapy is an ideal strategy to overcome immunosuppression and expose TAAs; therefore, they may work synergistically with DC vaccines. In this study, we demonstrate that oncolytic virus M1 (OVM) can enhance the antitumor effects of DC vaccines across diverse syngeneic mouse tumor models by increasing the infiltration of CD8+ effector T cells in the TME. Mechanically, we show that tumor cells counteract DC vaccines through the SIRPα-CD47 immune checkpoint, while OVM can downregulate SIRPα in DCs and CD47 in tumor cells. Since OVM upregulates PD-L1 in DCs, combining PD-L1 blockade with DC vaccines and OVM further enhances antitumor activity. Overall, OVM strengthens the antitumor efficacy of DC vaccines by targeting the SIRPα-CD47 axis, which exerts dominant immunosuppressive effects on DC vaccines.


Assuntos
Vírus Oncolíticos , Vacinas , Camundongos , Animais , Vírus Oncolíticos/genética , Antígeno CD47/genética , Antígeno B7-H1 , Linhagem Celular Tumoral , Antígenos de Neoplasias
5.
J Neurooncol ; 109(1): 53-62, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22562416

RESUMO

Malignant glioma is the most devastating and aggressive tumor in brain, characterized by rapid proliferation and diffuse invasion. Chemotherapy and radiotherapy are the pivotal strategies after surgery; however, high drug resistance of malignant glioma and the blood-brain barrier usually render chemotherapy drugs ineffective. Here, we find that triptolide, a small molecule with high lipid solubility, is capable of inhibiting proliferation and invasion of malignant glioma cells effectively. In both investigated malignant glioma cell lines, triptolide repressed cell proliferation via inducing cell cycle arrest in G0/G1 phase, associated with downregulation of G0/G1 cell cycle regulators cyclin D1, CDK4, and CDK6 followed by reduced phosphorylation of retinoblastoma protein (Rb). In addition, triptolide induced morphological change of C6 cells through downregulation of protein expression of MAP-2 and inhibition of activities of GTPases Cdc42 and Rac1/2/3, thus significantly suppressing migratory and invasive capacity. Moreover, in an in vivo tumor model, triptolide delayed growth of malignant glioma xenografts. These findings suggest an important inhibitory action of triptolide on proliferation and invasion of malignant glioma, and encourage triptolide as a candidate for glioma therapy.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos/farmacologia , Glioma/patologia , Fenantrenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Ciclo Celular/efeitos dos fármacos , Quinases Ciclina-Dependentes/metabolismo , Compostos de Epóxi/farmacologia , Feminino , Citometria de Fluxo , Glioma/tratamento farmacológico , Glioma/metabolismo , Camundongos , Camundongos Nus , Invasividade Neoplásica , Ratos , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína RAC2 de Ligação ao GTP
6.
Respiration ; 84(6): 509-17, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23006535

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease without beneficial therapy, except for lung transplantation. A high oral dose of N-acetylcysteine (NAC) added to prednisone and azathioprine has been found to improve lung function in IPF patients, though the mechanism of action remains poorly understood. OBJECTIVE: Based on our previous findings showing elevation of glutathione (GSH) content associated with downregulation of lysyl oxidase (LOX) activity, which is essential for collagen deposition, the aim of the present study was to test the hypothesis that NAC alleviates IPF by regulating LOX function. METHODS: We firstly analyzed the time course of collagen deposition in lung tissue, hydroxyproline content, LOX activity, GSH levels, and transforming growth factor-ß(1) (TGF-ß(1)) and α-smooth muscle actin (α-SMA) expression in bleomycin (BLM)-induced pulmonary fibrosis in a rat model. Then, we focused our studies on NAC modulation of LOX activity. RESULTS: LOX activity was increased on day 9 and peaked 14 days after BLM administration, while TGF-ß(1) protein peaked on day 9. Interestingly, NAC treatment for 14 days from day 0 reversed LOX activity to normal levels and increased GSH levels in the lung of BLM-dosed rats. Consistently, NAC partially attenuated pulmonary fibrosis and inhibited TGF-ß(1) and α-SMA expression in this model. CONCLUSIONS: Our study supports a novel mechanism of NAC alleviating IPF by inhibition of LOX activity via elevation of lung GSH in BLM-induced pulmonary fibrosis. The TGF-ß(1)/α-SMA pathway may also play an important role in modulation of LOX activity.


Assuntos
Acetilcisteína/farmacologia , Sequestradores de Radicais Livres/farmacologia , Proteína-Lisina 6-Oxidase/metabolismo , Fibrose Pulmonar/metabolismo , Actinas/efeitos dos fármacos , Actinas/metabolismo , Animais , Antibióticos Antineoplásicos/efeitos adversos , Bleomicina/efeitos adversos , Colágeno/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Proteína-Lisina 6-Oxidase/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo
7.
Hum Gene Ther ; 32(3-4): 158-165, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33504253

RESUMO

Alphavirus M1 is a promising oncolytic virus for cancer therapy. Here, we constructed a fluorescent reporter virus for real-time visualization and quantification of M1 virus both in vitro and in vivo. The reporter-encoding M1 virus maintained the characteristics of parental virus in the aspects of structure, replication capacity, the feature to induce cytopathic cell death, and the property of tumor targeting. The fluorescence is positively correlated with virus replication both in vitro and in vivo. More importantly, the reporter can be stably expressed for at least 10 generations in a serial passage assay. In summary, we successfully constructed stable and authentic reporter viruses for studying M1 virus and provided a feasible technical route for gene modification of oncolytic virus M1.


Assuntos
Alphavirus , Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Alphavirus/genética , Linhagem Celular Tumoral , Humanos , Neoplasias/genética , Neoplasias/terapia , Vírus Oncolíticos/genética , Replicação Viral
8.
Acta Pharmacol Sin ; 31(5): 554-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20418892

RESUMO

AIM: To investigate the mechanism of bleomycin (BLM)-induced pulmonary fibrosis. METHODS: Cultured human fetal lung fibroblast (HLF) cells were exposed to bleomycin (BLM) at 0-30 microg/mL for 24 h. Western blot analysis was used to detect lysyl oxidase (LO) protein expression. Real-time RT-PCR was used to detect LO mRNA level. LO catalytic activity was measured using diaminopentane as a substrate and Amplex red as a hydrogen peroxide probe. Copper (Cu) concentration was detected by flame atomic absorption spectrophotometry. RESULTS: Exposure of HLF cells to BLM at 10 microg/mL and 30 microg/mL increased LO catalytic activity to 130% and 158% of the control in the conditioned media. The expression of LO mRNA was increased to 5.5-fold of the control in HLF cells exposure to BLM at 3 microg/mL. BLM at 3 microg/mL also increased the expression of 46 kDa preproLO, 50 kDa proLO and 32 kDa mature LO to 219%, 130%, and 135% of the control, respectively. The Cu concentrations in conditioned media of cultured HLF cells exposed to BLM (10 and 30 microg/mL) were increased significantly to 1.48 and 2.46-fold of the control, respectively. CONCLUSION: Bleomycin induces upregulation of LO in cultured human fetal lung fibroblasts, which may be the mechanism of bleomycin-induced pulmonary fibrosis.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Bleomicina/farmacologia , Fibroblastos/efeitos dos fármacos , Proteína-Lisina 6-Oxidase/genética , Fibrose Pulmonar/induzido quimicamente , Regulação para Cima/efeitos dos fármacos , Aminopropionitrilo/farmacologia , Linhagem Celular , Cobre/metabolismo , Feto/citologia , Fibroblastos/metabolismo , Humanos , Pulmão/citologia , Proteína-Lisina 6-Oxidase/metabolismo , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo
9.
Cell Death Dis ; 11(12): 1062, 2020 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-33311488

RESUMO

Reversing the highly immunosuppressive tumor microenvironment (TME) is essential to achieve long-term efficacy with cancer immunotherapy. Despite the impressive clinical response to checkpoint blockade in multiple types of cancer, only a minority of patients benefit from this approach. Here, we report that the oncolytic virus M1 induces immunogenic tumor cell death and subsequently restores the ability of dendritic cells to prime antitumor T cells. Intravenous injection of M1 disrupts immune tolerance in the privileged TME, reprogramming immune-silent (cold) tumors into immune-inflamed (hot) tumors. M1 elicits potent CD8+ T cell-dependent therapeutic effects and establishes long-term antitumor immune memory in poorly immunogenic tumor models. Pretreatment with M1 sensitizes refractory tumors to subsequent checkpoint blockade by boosting T-cell recruitment and upregulating the expression of PD-L1. These findings reveal the antitumor immunological mechanism of the M1 virus and indicated that oncolytic viruses are ideal cotreatments for checkpoint blockade immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Vírus Oncolíticos/metabolismo , Linfócitos T/imunologia , Animais , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Morte Celular Imunogênica/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Inflamação/genética , Injeções Intravenosas , Camundongos Endogâmicos C57BL , Vírus Oncolíticos/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
10.
Mol Oncol ; 13(7): 1589-1604, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31162799

RESUMO

Activation of the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway induces glial differentiation of glioblastoma (GBM) cells, but the mechanism by which microRNA (miRNA) regulate this process remains poorly understood. In this study, by performing miRNA genomics and loss- and gain-of-function assays in dibutyryl-cAMP-treated GBM cells, we identified a critical negative regulator, hsa-miR-1275, that modulates a set of genes involved in cancer progression, stem cell maintenance, and cell maturation and differentiation. Additionally, we confirmed that miR-1275 directly and negatively regulates the protein expression of glial fibrillary acidic protein (GFAP), a marker of mature astrocytes. Of note, tri-methyl-histone H3 (Lys27) (H3K27me3), downstream of the PKA/polycomb repressive complex 2 (PRC2) pathway, accounts for the downregulation of miR-1275. Furthermore, decreased miR-1275 expression and induction of GFAP expression were also observed in dibutyryl-cAMP-treated primary cultured GBM cells. In a patient-derived glioma stem cell tumor model, a cAMP elevator and an inhibitor of H3K27me3 methyltransferase inhibited tumor growth, induced differentiation, and reduced expression of miR-1275. In summary, our study shows that epigenetic inhibition of miR-1275 by the cAMP/PKA/PRC2/H3K27me3 pathway mediates glial induction of GBM cells, providing a new mechanism and novel targets for differentiation-inducing therapy.


Assuntos
Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Histonas/metabolismo , MicroRNAs/genética , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Metilação , Camundongos Endogâmicos BALB C , Neuroglia/metabolismo , Neuroglia/patologia , Transcriptoma
11.
Hum Gene Ther ; 29(8): 950-961, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28750564

RESUMO

Oncolytic virotherapy is a novel and intriguing treatment strategy for cancer therapy. However, the clinical potential of oncolytic virus as single agent is limited. M1 virus is a promising oncolytic virus that has been tested in preclinical studies. In this study, we investigated the effect of the combination use of M1 virus and Bcl-2 family inhibitors. A chemical compounds screening including ten Bcl-2 family inhibitors demonstrated that pan-Bcl-2 inhibitors selectively augmented M1 virus oncolysis in cancer cells at very low doses. The mechanism of the enhanced antitumor effect of pan-Bcl-2 inhibitors with M1 virus is mainly due to the inhibition of Bcl-xL, which synergizes with M1-induced upregulation of Bak to trigger apoptosis. In xenograft mouse models and patient-derived tumor tissues, the combination of M1 and pan-Bcl-2 inhibitors significantly inhibited tumor growth and prolonged survival, suggesting the potential therapeutic value of this strategy. These findings offer insights into the synergy between Bcl-xL inhibition and oncolytic virus M1 as a combination anticancer treatment modality.


Assuntos
Neoplasias/genética , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Terapia Combinada , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/virologia , Vírus Oncolíticos/genética , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Nat Commun ; 9(1): 4342, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30337542

RESUMO

Oncolytic virotherapy is a promising therapeutic strategy that uses replication-competent viruses to selectively destroy malignancies. However, the therapeutic effect of certain oncolytic viruses (OVs) varies among cancer patients. Thus, it is necessary to overcome resistance to OVs through rationally designed combination strategies. Here, through an anticancer drug screening, we show that DNA-dependent protein kinase (DNA-PK) inhibition sensitizes cancer cells to OV M1 and improves therapeutic effects in refractory cancer models in vivo and in patient tumour samples. Infection of M1 virus triggers the transcription of interferons (IFNs) and the activation of the antiviral response, which can be abolished by pretreatment of DNA-PK inhibitor (DNA-PKI), resulting in selectively enhanced replication of OV M1 within malignancies. Furthermore, DNA-PK inhibition promotes the DNA damage response induced by M1 virus, leading to increased tumour cell apoptosis. Together, our study identifies the combination of DNA-PKI and OV M1 as a potential treatment for cancers.


Assuntos
Antivirais/farmacologia , Dano ao DNA , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Vírus Oncolíticos/fisiologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Terapia Combinada , Proteína Quinase Ativada por DNA/metabolismo , Avaliação Pré-Clínica de Medicamentos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Terapia Viral Oncolítica , Inibidores de Proteínas Quinases/farmacologia , Ratos
13.
Nat Commun ; 9(1): 1524, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29670091

RESUMO

Oncolytic virus is an attractive anticancer agent that selectively lyses cancer through targeting cancer cells rather than normal cells. Although M1 virus is effective against several cancer types, certain cancer cells present low sensitivity to it. Here we identified that most of the components in the cholesterol biosynthesis pathway are downregulated after M1 virus infection. Further functional studies illustrate that mevalonate/protein farnesylation/ras homolog family member Q (RHOQ) axis inhibits M1 virus replication. Further transcriptome analysis shows that RHOQ knockdown obviously suppresses Rab GTPase and ATP-mediated membrane transporter system, which may mediate the antiviral effect of RHOQ. Based on this, inhibition of the above pathway significantly enhances the anticancer potency of M1 virus in vitro, in vivo, and ex vivo. Our research provides an intriguing strategy for the rational combination of M1 virus with farnesyl transferase inhibitors to enhance therapeutic efficacy.


Assuntos
Colesterol/química , Ácido Mevalônico/antagonistas & inibidores , Ácido Mevalônico/metabolismo , Terapia Viral Oncolítica , Vírus Oncolíticos/fisiologia , Replicação Viral , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Farnesiltranstransferase/antagonistas & inibidores , Feminino , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Prenilação de Proteína , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
14.
Neuroscience ; 350: 110-123, 2017 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-28336411

RESUMO

Acute stress impairs the hippocampus-dependent spatial memory retrieval, and its synaptic mechanisms are associated with hippocampal CA1 long-term depression (LTD) enhancement in the adult rats. Endogenous hydrogen sulfide (H2S) is recognized as a novel gasotransmitter and has the neural protective roles. However, very little attention has been paid to understanding the effects of H2S on spatial memory retrieval impairment. We observed the protective effects of NaHS (a donor of H2S) against spatial memory retrieval impairment caused by acute stress and its synaptic mechanisms. Our results showed that NaHS abolished spatial memory retrieval impairment and hippocampal CA1 LTD enhancement caused by acute stress, but not by glutamate transporter inhibitor l-trans-pyrrolidine-2,4-dicarboxylic (tPDC), indicating that the activation of glutamate transporters is necessary for exogenous H2S to exert its roles. Moreover, NaHS restored the decreased glutamate uptake in the hippocampal CA1 synaptosomal fraction caused by acute stress. Dithiothreitol (DTT, a disulfide reducing agent) abolished a decrease in the glutamate uptake caused by acute stress, and NaHS eradicated the decreased glutamate uptake caused by 5,5'-dithio-bis(2-nitrobenzoic)acid (DTNB, a thiol oxidizing agent), collectively, revealing that exogenous H2S increases glutamate uptake by reducing disulfide bonds of the glutamate transporters. Additionally, NaHS inhibited the increased expression level of phosphorylated c-Jun-N-terminal kinase (JNK) in the hippocampal CA1 region caused by acute stress. The JNK inhibitor SP600125 eliminated spatial memory retrieval impairment, hippocampal CA1 LTD enhancement and the decreased glutamate uptake caused by acute stress, indicating that exogenous H2S exerts these roles by inhibiting the activation of JNK signaling pathway.


Assuntos
Ácido Glutâmico/metabolismo , Hipocampo/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Memória Espacial/efeitos dos fármacos , Estresse Psicológico/metabolismo , Animais , Hipocampo/metabolismo , Depressão Sináptica de Longo Prazo/fisiologia , Masculino , Transtornos da Memória/metabolismo , Plasticidade Neuronal/fisiologia , Ratos Sprague-Dawley
15.
Sci Transl Med ; 9(404)2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28835517

RESUMO

Oncolytic virotherapy is rapidly progressing through clinical evaluation. However, the therapeutic efficacy of oncolytic viruses in humans has been less than expected from preclinical studies. We describe an anticancer drug screen for compounds that enhance M1 oncolytic virus activity in hepatocellular carcinoma (HCC). An inhibitor of the valosin-containing protein (VCP) was identified as the top sensitizer, selectively increasing potency of the oncolytic virus up to 3600-fold. Further investigation revealed that VCP inhibitors cooperated with M1 virus-suppressed inositol-requiring enzyme 1α (IRE1α)-X-box binding protein 1 (XBP1) pathway and triggered irresolvable endoplasmic reticulum (ER) stress, subsequently promoting robust apoptosis in HCC. We show that VCP inhibitor improved the oncolytic efficacy of M1 virus in several mouse models of HCC and primary HCC tissues. Finally, this combinatorial therapeutic strategy was well tolerated in nonhuman primates. Our study identifies combined VCP inhibition and oncolytic virus as a potential treatment for HCC and demonstrates promising therapeutic potential.


Assuntos
Antineoplásicos/metabolismo , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/virologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/virologia , Vírus Oncolíticos/metabolismo , Proteína com Valosina/antagonistas & inibidores , Animais , Apoptose , Efeito Espectador , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Terapia Combinada , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Neoplasias Hepáticas/patologia , Vírus Oncolíticos/patogenicidade , Primatas , Proteínas Serina-Treonina Quinases/metabolismo , Proteína com Valosina/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo
16.
Cell Rep ; 18(2): 468-481, 2017 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-28076790

RESUMO

Glioblastoma multiforme (GBM) is among the most aggressive of human cancers. Although differentiation therapy has been proposed as a potential approach to treat GBM, the mechanisms of induced differentiation remain poorly defined. Here, we established an induced differentiation model of GBM using cAMP activators that specifically directed GBM differentiation into astroglia. Transcriptomic and proteomic analyses revealed that oxidative phosphorylation and mitochondrial biogenesis are involved in induced differentiation of GBM. Dibutyryl cyclic AMP (dbcAMP) reverses the Warburg effect, as evidenced by increased oxygen consumption and reduced lactate production. Mitochondrial biogenesis induced by activation of the CREB-PGC1α pathway triggers metabolic shift and differentiation. Blocking mitochondrial biogenesis using mdivi1 or by silencing PGC1α abrogates differentiation; conversely, overexpression of PGC1α elicits differentiation. In GBM xenograft models and patient-derived GBM samples, cAMP activators also induce tumor growth inhibition and differentiation. Our data show that mitochondrial biogenesis and metabolic switch to oxidative phosphorylation drive the differentiation of tumor cells.


Assuntos
Astrócitos/patologia , Neoplasias Encefálicas/patologia , Diferenciação Celular , AMP Cíclico/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Glicólise , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Astrócitos/metabolismo , Astrócitos/ultraestrutura , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/ultraestrutura , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Perfilação da Expressão Gênica , Proteína Glial Fibrilar Ácida/metabolismo , Glioblastoma/genética , Glioblastoma/ultraestrutura , Glicólise/efeitos dos fármacos , Humanos , Biogênese de Organelas , Fosforilação Oxidativa/efeitos dos fármacos , Proteômica , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
17.
BMC Genomics ; 7: 152, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16776837

RESUMO

BACKGROUND: The snake venom gland is a specialized organ, which synthesizes and secretes the complex and abundant toxin proteins. Though gene expression in the snake venom gland has been extensively studied, the focus has been on the components of the venom. As far as the molecular mechanism of toxin secretion and metabolism is concerned, we still knew a little. Therefore, a fundamental question being arisen is what genes are expressed in the snake venom glands besides many toxin components? RESULTS: To examine extensively the transcripts expressed in the venom gland of Deinagkistrodon acutus and unveil the potential of its products on cellular structure and functional aspects, we generated 8696 expressed sequence tags (ESTs) from a non-normalized cDNA library. All ESTs were clustered into 3416 clusters, of which 40.16% of total ESTs belong to recognized toxin-coding sequences; 39.85% are similar to cellular transcripts; and 20.00% have no significant similarity to any known sequences. By analyzing cellular functional transcripts, we found high expression of some venom related genes and gland-specific genes, such as calglandulin EF-hand protein gene and protein disulfide isomerase gene. The transcripts of creatine kinase and NADH dehydrogenase were also identified at high level. Moreover, abundant cellular structural proteins similar to mammalian muscle tissues were also identified. The phylogenetic analysis of two snake venom toxin families of group III metalloproteinase and serine protease in suborder Colubroidea showed an early single recruitment event in the viperids evolutionary process. CONCLUSION: Gene cataloguing and profiling of the venom gland of Deinagkistrodon acutus is an essential requisite to provide molecular reagents for functional genomic studies needed for elucidating mechanisms of action of toxins and surveying physiological events taking place in the very specialized secretory tissue. So this study provides a first global view of the genetic programs for the venom gland of Deinagkistrodon acutus described so far and an insight into molecular mechanism of toxin secreting.


Assuntos
Venenos de Crotalídeos/genética , Transcrição Gênica , Animais , Biologia Computacional , Venenos de Crotalídeos/classificação , Metabolismo Energético , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Filogenia , Viperidae
18.
Steroids ; 105: 96-105, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26631550

RESUMO

Steroids have been shown to have multiple effects on the nervous system including neuroprotective activities, and they have the potential to be used for the treatment of neurodegenerative diseases. In this current study, we tested the hypothesis that the marine steroid 24-methylenecholestane-3ß,5α,6ß,19-tetraol (Tetrol) has a neuroprotective effect. (1) We synthesized Tetrol through a multiple step reaction starting from hyodeoxycholic acid (HDCA). (2) We then evaluated the neuroprotective effect of Tetrol with a glutamate-induced neuronal injury model in vitro. Tetrol concentration dependently increased the survival rate of cerebellar granule neurons challenged with toxic concentration of glutamate. Consistently, Tetrol significantly decreased glutamate-induced lactate dehydrogenase (LDH) release with a threshold concentration of 2.5 µM. (3) We further evaluated the neuroprotective effect of Tetrol in a middle cerebral artery occlusion (MCAO)-induced cerebral ischemia model in rat. Tetrol, at a dose of 12 mg/kg, significantly decreased MCAO-induced infarction volume by ∼50%. (4) Finally, we probed the mechanism and found that Tetrol concentration dependently attenuated N-methyl-d-aspartate (NMDA)-induced intracellular calcium ([Ca(2+)]i) increase with an IC50 of 7.8±0.62 µM, and inhibited NMDA currents in cortical neurons with an IC50 of 10.28±0.71 µM. Taken together, we have synthesized and characterized Tetrol as a novel neuroprotectant through negative modulation of NMDA receptors.


Assuntos
Organismos Aquáticos/química , Colestanóis/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Córtex Cerebral/patologia , Colestanóis/síntese química , Colestanóis/química , Colestanóis/uso terapêutico , Ácido Glutâmico/toxicidade , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , N-Metilaspartato/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Ratos Sprague-Dawley
19.
Hum Gene Ther ; 27(9): 700-11, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27296553

RESUMO

Cancers figure among the leading causes of morbidity and mortality worldwide. The number of new cases is expected to rise by about 70% over the next 2 decades. Development of novel therapeutic agents is urgently needed for clinical cancer therapy. Alphavirus M1 is a Getah-like virus isolated from China with a genome of positive single-strand RNA. We have previously identified that alphavirus M1 is a naturally existing oncolytic virus with significant anticancer activity against different kinds of cancer (e.g., liver cancer, bladder cancer, and colon cancer). To support the incoming clinical trial of intravenous administration of alphavirus M1 to cancer patients, we assessed the safety of M1 in adult nonhuman primates. We previously presented the genome sequencing data of the cynomolgus macaques (Macaca fascicularis), which was demonstrated as an ideal animal species for virus infection study. Therefore, we chose cynomolgus macaques of either sex for the present safety study of oncolytic virus M1. In the first round of administration, five experimental macaques were intravenously injected with six times of oncolytic virus M1 (1 × 10(9) pfu/dose) in 1 week, compared with five vehicle-injected control animals. The last two rounds of injections were further completed in the following months in the same way as the first round. Body weight, temperature, complete blood count, clinical biochemistries, cytokine profiles, lymphocytes subsets, neutralizing antibody, and clinical symptoms were closely monitored at different time points. Magnetic resonance imaging was also performed to assess the possibility of encephalitis or arthritis. As a result, no clinical, biochemical, immunological, or medical imaging or other pathological evidence of toxicity was found during the whole process of the study. Our results in cynomolgus macaques suggested the safety of intravenous administration of oncolytic virus M1 in cancer patients in the future.


Assuntos
Alphavirus/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vetores Genéticos/administração & dosagem , Vírus Oncolíticos/imunologia , Alphavirus/genética , Animais , Modelos Animais de Doenças , Feminino , Humanos , Injeções Intravenosas , Macaca fascicularis , Masculino , Vírus Oncolíticos/genética
20.
Nat Commun ; 7: 13107, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27708285

RESUMO

Snakes have numerous features distinctive from other tetrapods and a rich history of genome evolution that is still obscure. Here, we report the high-quality genome of the five-pacer viper, Deinagkistrodon acutus, and comparative analyses with other representative snake and lizard genomes. We map the evolutionary trajectories of transposable elements (TEs), developmental genes and sex chromosomes onto the snake phylogeny. TEs exhibit dynamic lineage-specific expansion, and many viper TEs show brain-specific gene expression along with their nearby genes. We detect signatures of adaptive evolution in olfactory, venom and thermal-sensing genes and also functional degeneration of genes associated with vision and hearing. Lineage-specific relaxation of functional constraints on respective Hox and Tbx limb-patterning genes supports fossil evidence for a successive loss of forelimbs then hindlimbs during snake evolution. Finally, we infer that the ZW sex chromosome pair had undergone at least three recombination suppression events in the ancestor of advanced snakes. These results altogether forge a framework for our deep understanding into snakes' history of molecular evolution.


Assuntos
Evolução Biológica , Elementos de DNA Transponíveis , Serpentes/anatomia & histologia , Serpentes/genética , Animais , Linhagem da Célula , Evolução Molecular , Feminino , Membro Anterior , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genoma , Membro Posterior , Lagartos/genética , Masculino , Filogenia , Recombinação Genética , Cromossomos Sexuais , Transcriptoma
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