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1.
Inflamm Res ; 73(9): 1581-1599, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39052064

RESUMO

OBJECTIVE AND DESIGN: The exact immunological mechanism of widespread chronic inflammatory skin disorder psoriasis has not been fully established. CD11b+Gr.1+ myeloid-derived cells are immature heterogeneous cells with T-cell suppressive property in neoplasia; however, influence of these cells on adaptive immunity is highly contextual; therefore, we dubbed these cells as myeloid-derived adjuster cells (MDAC). We studied imiquimod induced psoriasis in mouse model and evaluated for the first time the RORγt-NFAT1 axis in MDACs and the function, differentiation and interaction of these cells with T cells. MATERIALS AND METHODS: The status of T cells and MDACs; their functionality and differentiation properties, and the roles of RORγt and NFAT1 in MDACs were evaluated using flow cytometry, qRT-PCR and confocal imaging. RESULTS: We found gradual increase in T cells and MDACs and an increase in the number of IL17 -secreting MDACs and T cells in the skin of psoriatic animals. We also noted that MDAC differentiation is biased toward M1 macrophages and DCs which perpetuate inflammation. We found that psoriatic MDACs were unable to suppress T-cell proliferation or activation but seemingly helped these T cells produce more IL17. Inhibition of the RORγt/NFAT1 axis in MDACs increased the suppressive nature of MDACs, allowing these cells to suppress the activity of psoriatic T-cells. CONCLUSION: Our results indicate that altered MDAC properties in psoriatic condition sustains pathological inflammation and RORγt and NFAT1 as promising intervention target for psoriasis management.


Assuntos
Antígeno CD11b , Diferenciação Celular , Imiquimode , Interleucina-17 , Fatores de Transcrição NFATC , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Psoríase , Animais , Camundongos , Antígenos Ly , Antígeno CD11b/metabolismo , Diferenciação Celular/efeitos dos fármacos , Inflamação/induzido quimicamente , Interleucina-17/metabolismo , Camundongos Endogâmicos BALB C , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Células Mieloides/imunologia , Fatores de Transcrição NFATC/metabolismo , Fatores de Transcrição NFATC/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Fenótipo , Psoríase/induzido quimicamente , Psoríase/imunologia , Pele/patologia , Pele/imunologia , Pele/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Masculino
2.
ChemMedChem ; 19(17): e202300728, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38757641

RESUMO

Synthesis of non-platinum transition metal complexes with N,O donor chelating ligand for application against pathogenesis of cancer with higher efficacy and selectivity is currently an important field of research. We assessed the anti-cancer effect of a mixed ligand Ni(II) complex on human breast and lung cancer cell lines in this investigation. Mononuclear mixed ligand octahedral Ni(II) complex [NiIIL(NO3)(MeOH)] complex (1), with tri-dentate phenol-based ligand 2,4-dichloro-6-((4-methylpiperazin-1-yl) methyl) phenol (HL) along with methanol and nitrate as ancillary ligand was prepared. Piperazine moiety of the ligand exists as boat conformation in this complex as revealed from single crystal X-ray study. UV-visible spectrum of complex (1) exhibits three distinct d-d bands due to spin-allowed 3 A2 g→3T1 g (P), 3 A2 g→3T1 g(F) and 3 A2 g→3T2 g(F) transitions as expected in an octahedral d8 system. Our study revealed that Complex (1) induces apoptotic cell death in mouse and human cancer cells such as mcf-7, A549 and MDA-MB-231 through transactivation of p53 and its pro-apoptotic downstream targets in a dose dependent manner. Furthermore, complex (1) was able to slow the migratory rate of MDA-MB-231 cells' in vitro as well as epithelia -mesenchymal transition (EMT), the key step for metastatic transition and malignancy. Over all our results suggest complex (1) as a potential agent in anti-tumor treatment regimen showing both cytotoxic and anti-metastatic activity against malignant neoplasia.


Assuntos
Antineoplásicos , Apoptose , Movimento Celular , Proliferação de Células , Complexos de Coordenação , Ensaios de Seleção de Medicamentos Antitumorais , Níquel , Humanos , Níquel/química , Níquel/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Piperazinas/farmacologia , Piperazinas/química , Piperazinas/síntese química , Linhagem Celular Tumoral , Animais
3.
J Leukoc Biol ; 115(5): 958-984, 2024 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-38236200

RESUMO

Myeloid-derived suppressor cells are heterogenous immature myeloid lineage cells that can differentiate into neutrophils, monocytes, and dendritic cells as well. These cells have been characterized to have potent immunosuppressive capacity in neoplasia and a neoplastic chronic inflammatory microenvironment. Increased accumulation of myeloid-derived suppressor cells was reported with poor clinical outcomes in patients. They support neoplastic progression by abrogating antitumor immunity through inhibition of lymphocyte functions and directly by facilitating tumor development. Yet the shifting genetic signatures of this myeloid lineage cell toward immunosuppressive functionality in progressive tumor development remain elusive. We have attempted to identify the gene expression profile using lineage-specific markers of these unique myeloid lineage cells in a tumor microenvironment and bone marrow using a liquid transplantable mice tumor model to trace the changing influence of the tumor microenvironment on myeloid-derived suppressor cells. We analyzed the phenotype, functional shift, suppressive activity, differentiation status, and microarray-based gene expression profile of CD11b+Gr1+ lineage-specific cells isolated from the tumor microenvironment and bone marrow of 4 stages of tumor-bearing mice and compared them with control counterparts. Our analysis of differentially expressed genes of myeloid-derived suppressor cells isolated from bone marrow and the tumor microenvironment reveals unique gene expression patterns in the bone marrow and tumor microenvironment-derived myeloid-derived suppressor cells. It also suggests T-cell suppressive activity of myeloid-derived suppressor cells progressively increases toward the mid-to-late phase of the tumor and a significant differentiation bias of tumor site myeloid-derived suppressor cells toward macrophages, even in the presence of differentiating agents, indicating potential molecular characteristics of myeloid-derived suppressor cells in different stages of the tumor that can emerge as an intervention target.


Assuntos
Diferenciação Celular , Progressão da Doença , Células Supressoras Mieloides , Microambiente Tumoral , Animais , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Células Supressoras Mieloides/patologia , Microambiente Tumoral/imunologia , Camundongos , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Camundongos Endogâmicos C57BL , Células da Medula Óssea/metabolismo , Antígeno CD11b/metabolismo , Antígeno CD11b/genética , Medula Óssea/patologia , Medula Óssea/metabolismo
4.
Phytomedicine ; 119: 155007, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37549537

RESUMO

BACKGROUND: 1-2.88% of human populations are affected by psoriasis, one type of chronic inflammatory skin disease. Skin thickenings, erythema, scaling in skin are the most important symptoms of psoriasis. There are renewed interests amongst scientists in studying anti-inflammatory property of the plant extracts due to lower side effects and cost effectiveness. There are few reports suggesting anti-inflammatory activity of Premna herbacea roxb. but lacks systematic evaluation of these properties. METHODS: We, initially tested the anti-inflammatory activity of crude root methanolic extract in vitro, where it significantly reduced LPS generated ROS in splenic macrophages. We further tested the TLC and HPLC fraction in order to find active ingredient in Premna herbacea roxb. root extract that ameliorated the chronic inflammation of skin and performed GC-MS and LC-MS studies to identify active component. Upon finding significant anti-inflammatory effect of the crude root extract in vitro, We studied the efficacy of the Premna herbacea roxb. root extract in Imiquimod induced psoriasis like skin inflammation in male BALB/C mice that closely resembles human psoriasis. Immunophenotyping, Cytokine productions were observed by flow cytometry, status of gene expression was done by Real time PCR and nuclear co-localization was studied by confocal microscopy. RESULTS: We observed progressive increase in signs and symptoms of the disease in imiquimod treated diseased animals but the Premna herbacea roxb. Root Methanolic Extract (PHRME) reduced the thickening of the skin, redness and scaling in these animals. In our study, along with progression of the disease, the production of macrophages increases and with the application of PHRME, the percentage of macrophages have reduced. CONCLUSION: As per the previous Indigenous traditional knowledge regarding use of Premna herbacea roxb. against inflammatory disorder and lack of detail mechanistic study of the crude root extract prompted us to elucidate the efficacy of the root extract in vitro and in vivo psoriatic mice model. For the first time we have identified three putative bioactive active components (5­hydroxy-7-methoxyflavanone, 3-Hydroxy-7,8,2',3'-tetramethoxyflavone, 2,4',6'-trimethoxy chalcone) from Premna herbacea root methanolic extract (PHRME) and we suggest PHRME and purified active fractions influence NFκB and COX2 signaling pathway to suppress inflammatory conditions. All of the purified components show strong binding efficiency in our molecular docking analysis. Our study also suggests that Premna herbacea roxb. root extract may be explored as cost effective alternative for established treatment regimen as our study also indicates low side effect of the extract against pre-clinical psoriatic model.


Assuntos
Psoríase , Camundongos , Humanos , Animais , Imiquimode , Simulação de Acoplamento Molecular , Camundongos Endogâmicos BALB C , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Pele , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Macrófagos/metabolismo , Modelos Animais de Doenças , Citocinas/metabolismo
5.
Cancer Immunol Res ; 11(3): 364-380, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36574614

RESUMO

B cells are an essential component of humoral immunity. Their primary function is to mount antigen-specific antibody responses to eliminate pathogens. Despite an increase in B-cell number, we found that serum-IgG levels were low in patients with breast cancer. To solve this conundrum, we used high-dimensional flow cytometry to analyze the heterogeneity of B-cell populations and identified a tumor-specific CD19+CD24hiCD38hi IL10-producing B regulatory (Breg)-cell subset. Although IL10 is a Breg-cell marker, being an intracellular protein, it is of limited value for Breg-cell isolation. Highly expressed Breg-cell surface proteins CD24 and CD38 also impede the isolation of viable Breg cells. These are hurdles that limit understanding of Breg-cell functions. Our transcriptomic analysis identified, CD39-negativity as an exclusive, sorting-friendly surface marker for tumor-associated Breg cells. We found that the identified CD19+CD39‒IL10+ B-cell population was suppressive in nature as it limited T helper-cell proliferation, type-1 cytokine production, and T effector-cell survival, and augmented CD4+FOXP3+ regulatory T-cell generation. These tumor-associated Breg cells were also found to restrict autologous T follicular helper-cell expansion and IL21 secretion, thereby inhibiting germinal transcript formation and activation-induced cytidine deaminase expression involved in H-chain class-switch recombination (CSR). This isotype-switching abnormality was shown to hinder B-cell differentiation into class-switched memory B cells and subsequent high-affinity antibody-producing plasma B cells, which collectively led to the dampening of IgG-mediated antibody responses in patients with cancer. As low IgG is associated with poor prognosis in patients with cancer, Breg-cell depletion could be a promising future therapy for boosting plasma B cell-mediated antibody responses.


Assuntos
Interleucina-10 , Neoplasias , Humanos , Formação de Anticorpos , Antígenos CD19 , Linfócitos T CD4-Positivos , Imunoglobulina G
6.
Int Immunopharmacol ; 114: 109521, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36470118

RESUMO

In clinical practice, major efforts are underway to identify appropriate drug combinations to boost anticancer activity while suppressing unwanted adverse effects. In this regard, we evaluated the efficacy of combination treatment with the widely used chemotherapeutic drug doxorubicin along with the TGFßRI inhibitor galunisertib (LY2157299) in aggressive B-cell non-Hodgkin lymphoma (B-NHL). The antiproliferative effects of these drugs as single agents or in combination against several B-NHL cell lines and the synergism of the drug combination were evaluated by calculating the combination index. To understand the putative molecular mechanism of drug synergism, the TGF-ß and stress signaling pathways were analyzed after combination treatment. An aggressive lymphoma model was used to evaluate the anticancer activity and post-therapeutic immune response of the drug combination in vivo. Galunisertib sensitized various B-NHL cells to doxorubicin and in combination synergistically increased apoptosis. The antitumor activity of the drug combinations involved upregulation of p-P38 MAPK and inhibition of the TGF-ß/Smad2/3 and PI3K/AKT signaling pathways. Combined drug treatment significantly reduced tumor growth and enhanced survival, indicating that the synergism between galunisertib and Dox observed in vitro was most likely retained in vivo. Based on the tumor-draining lymph node analysis, combination therapy results in better prognosis, including disappearance of disease-exacerbating regulatory T cells and prevention of CD8+ T-cell exhaustion by downregulating MDSCs. Galunisertib synergistically potentiates the doxorubicin-mediated antitumor effect without aggravating the toxic effects and the ability to kickstart the immune system, supporting the clinical relevance of targeting TGF-ßRI in combination with doxorubicin against lymphoma.


Assuntos
Linfoma , Neoplasias , Humanos , Fosfatidilinositol 3-Quinases/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias/tratamento farmacológico , Fator de Crescimento Transformador beta , Sistema Imunitário , Sinergismo Farmacológico , Linhagem Celular Tumoral , Apoptose
7.
Anal Methods ; 14(33): 3196-3202, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35938936

RESUMO

A new benzorhodol-based non-fluorescent organic frame (DEB-CO) detects carbon monoxide (CO) selectively through a spirolactam ring-opening mechanism. Herein, the selective off-on fluorogenic behavior of this probe towards CO has been achieved without any assistance of precious and hazardous metals (e.g. Pd2+) as additional substrates. Moreover, the red-emissive probe motivated us to apply in situ tracing in mice and living cells. The selective off-on fluorogenic behavior of this probe towards CO originating from CORM-3 in vitro and in vivo with a limit of detection as low as 64.29 nM (for CORM-3) has been observed. Additionally, this probe is capable of sensing toxic carbon monoxide gas. This probe has also been utilized to detect intracellular CO in MCF7 cells (in vitro) and to spot the distribution of CO in mice (in vivo) by acquiring bioimages with the help of confocal microscopy, which indicates that DEB-CO is a smart competent probe for this purpose.


Assuntos
Monóxido de Carbono , Corantes Fluorescentes , Animais , Humanos , Células MCF-7 , Metais , Camundongos , Microscopia Confocal
8.
Life Sci ; 305: 120755, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35780842

RESUMO

The tumor microenvironment is a complex domain that not only contains tumor cells but also a plethora of other host immune cells. By nature, the tumor microenvironment is a highly immunosuppressive milieu providing growing conditions for tumor cells. A major immune cell population that contributes most in the development of this immunosuppressive microenvironment is the MDSC, a heterogenous population of immature cells. Although found in small numbers only in the bone marrow of healthy individuals, they readily migrate to the lymph nodes and tumor site during cancer pathogenesis. MDSC mediated disruption of antitumor T cell activity is a major cause of the immunosuppression at the tumor site, but recent findings have shown that MDSC mediated dysfunction of other major immune cells might also play an important role. In this article we will review how crosstalk with MDSC alters the activity of both conventional and unconventional immune cells that inhibits the antitumor immunity and promotes cancer progression.


Assuntos
Células Supressoras Mieloides , Neoplasias , Humanos , Terapia de Imunossupressão , Neoplasias/patologia , Linfócitos T , Microambiente Tumoral
9.
Carbohydr Polym ; 291: 119614, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698411

RESUMO

We report the solvent-free green synthesis of two Schiff bases, (E)-2-((2-hydroxy-3-methoxybenzylidene)amino)-4-methylphenol (SL1) and (E)-2-((2-hydroxybenzylidene) amino)-4-methylphenol (SL2), and their inclusion complexes with ß-cyclodextrin (ß-CD). The encapsulation phenomenon, structural characteristics and hydrolytic stabilities of the SL1, SL2 and their inclusion complexes are determined with a suite of spectroscopic, analytical and crystallographic analyses. Dose and time-dependent cytotoxicity study of SL1-ß-CD and SL2-ß-CD against two breast cancer cell lines, Michigan Cancer Foundation-7 (MCF-7) and metastatic mammary adenocarcinoma1 (MDA-MB-231), exhibit excellent inhibitory activity with significant non-cytotoxic concentrations and ensure a multifold elevation of bio-potency than the parent Schiff base compounds. The Annexin-V assay determines the efficacy of these inclusion complexes to trigger apoptosis, suggesting that SL2-ß-CD possesses better efficacy as an anti-cancer drug. To the best of our knowledge, we, for the first time, report the inclusion of nanocrystalline Schiff bases into ß-CD for multifold enrichment of bio-potency.


Assuntos
Antineoplásicos , beta-Ciclodextrinas , Antineoplásicos/química , Apoptose , Humanos , Células MCF-7 , Bases de Schiff/química , beta-Ciclodextrinas/farmacologia
10.
Front Pharmacol ; 13: 852065, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444547

RESUMO

Integrative medicine practices, such as Ayurveda, are popular in India and many South Asian countries, yet basic research to investigate the concepts, procedures, and medical benefits of ayurvedic products has received little attention and is not fully understood. Here, we report a functional nanodiamond-based traditional Ayurvedic herbomineral formulation, Heerak Bhasma (Ayu_ND), for the treatment of solid tumors called Dalton's lymphoma generated in CD1 mice. Ayu_ND-mediated immunostimulation significantly reduces tumor cell proliferation and induces apoptosis aided by the active participation of dendritic cells. Immunomodulatory Ayu_ND treatment is highly immunostimulatory and drives dendritic cells to produce TNF-α. Treatment with Ayu_ND significantly reduces the tumor volume, inhibits metastasis in distant vascularized organs, and increases the life span of tumor-bearing animals compared with untreated littermates. These events were associated with elevated serum levels of the protective cytokines IFN-γ and TNF-α and downregulated the disease, exacerbating TGF-ß. Ayu_ND-mediated therapeutic success was also accompanied by the depletion of regulatory T cells and enhanced vaccine-induced T-cell immunity, guided by the restoration of the memory CD8+ T-cell pool and prevention of PD-1-mediated T cell exhaustion. The results provide a basis for further evaluation of ayurvedic formulations and drug efficacy in treating cancers.

11.
EBioMedicine ; 73: 103672, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34740102

RESUMO

BACKGROUND: Phospho-Akt1 (pAkt1) undergoes prolyl hydroxylation at Pro125 and Pro313 by the prolyl hydroxylase-2 (PHD2) in a reaction decarboxylating α-ketoglutarate (αKG). We investigated whether the αKG supplementation could inhibit Akt-mediated activation of platelets and monocytes, in vitro as well as in vivo, by augmenting PHD2 activity. METHODS: We treated platelets or monocytes isolated from healthy individuals with αKG in presence of agonists in vitro and assessed the signalling molecules including pAkt1. We supplemented mice with dietary αKG and estimated the functional responses of platelets and monocytes ex vivo. Further, we investigated the impact of dietary αKG on inflammation and thrombosis in lungs of mice either treated with thrombosis-inducing agent carrageenan or infected with SARS-CoV-2. FINDINGS: Octyl αKG supplementation to platelets promoted PHD2 activity through elevated intracellular αKG to succinate ratio, and reduced aggregation in vitro by suppressing pAkt1(Thr308). Augmented PHD2 activity was confirmed by increased hydroxylated-proline and enhanced binding of PHD2 to pAkt in αKG-treated platelets. Contrastingly, inhibitors of PHD2 significantly increased pAkt1 in platelets. Octyl-αKG followed similar mechanism in monocytes to inhibit cytokine secretion in vitro. Our data also describe a suppressed pAkt1 and reduced activation of platelets and leukocytes ex vivo from mice supplemented with dietary αKG, unaccompanied by alteration in their number. Dietary αKG significantly reduced clot formation and leukocyte accumulation in various organs including lungs of mice treated with thrombosis-inducing agent carrageenan. Importantly, in SARS-CoV-2 infected hamsters, we observed a significant rescue effect of dietary αKG on inflamed lungs with significantly reduced leukocyte accumulation, clot formation and viral load alongside down-modulation of pAkt in the lung of the infected animals. INTERPRETATION: Our study suggests that dietary αKG supplementation prevents Akt-driven maladies such as thrombosis and inflammation and rescues pathology of COVID19-infected lungs. FUNDING: Study was funded by the Department of Biotechnology (DBT), Govt. of India (grants: BT/PR22881 and BT/PR22985); and the Science and Engineering Research Board, Govt. of India (CRG/000092).


Assuntos
Ácidos Cetoglutáricos/uso terapêutico , Prolil Hidroxilases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombose/prevenção & controle , Animais , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , COVID-19/patologia , COVID-19/prevenção & controle , COVID-19/veterinária , COVID-19/virologia , Cricetinae , Suplementos Nutricionais , Regulação para Baixo/efeitos dos fármacos , Humanos , Ácidos Cetoglutáricos/farmacologia , Pulmão/metabolismo , Pulmão/patologia , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fosforilação , Agregação Plaquetária/efeitos dos fármacos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Trombose/induzido quimicamente , Trombose/patologia , Trombose/veterinária
13.
iScience ; 23(10): 101623, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33089111

RESUMO

Galunisertib (LY2157299) is a selective ATP-mimetic inhibitor of TGF-ß receptor-I activation, currently under clinical trial in a variety of cancers. We have tested the combined effects of galunisertib- and interleukin-15-activated dendritic cells in an aggressive and highly metastatic murine lymphoma. Based on the tumor-draining lymph node architecture, and its histology, the combination therapy results in better prognosis, including disappearance of the disease-exacerbating regulatory T cells. Our data suggest that galunisertib significantly enhances the success of immunotherapy with IL-15-activated dendritic cells by limiting the regulatory T cells generation with consequent downregulation of regulatory T cells in the tumor-draining lymph nodes and vascularized organ like spleen. This is also associated with consistent loss p-SMAD2 and downregulation of Neuropilin-1, leading to better prognosis and positive outcome. These results connect the role of combined therapy with the consequent elimination of disease-exacerbating T regulatory cells in a metastatic murine lymphoma.

14.
Life Sci ; 253: 117731, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353431

RESUMO

BACKGROUND: Very little is known about the role inflammation and mechanism(s) that enables the tumor to evade host's anti-tumor immune function during very initial days of tumor establishment. Our study focuses on the immune response and local inflammation specially the pro-inflammatory and immune modifier components that are responsible for tumor-induced immune-suppression, tumor-associated macrophages (TAM) at tumor microenvironment in mouse model from very early to late phase of tumor progression. METHODS: 1 × 105 Ascites tumor, EAC in Swiss albino or Sarcoma-180 (S-180) in Balb c mice strain were inoculated intra-peritonially and grouped into Control (0 day or no tumor), initial phase (3 day tumor), early (7 Day), Late (14 day) and terminal (21 day tumor) sets. T cell activity, tumor niche macrophage, inflammatory signatures were studied using Confocal microscopy, flowcytometry, ELISA, q-RT PCR and Western blot. RESULTS: We observed increased T cell infiltration at a very early stage of tumorigenesis in the tumor site with elevated percentage of activated/memory T cells. But increased cellular death and functional suppression of tumor site T cells during final stages. We observed increased infiltration of TAMs with skewed M2 phenotype. Increased chemokine receptor expression could be noted on these TAMs. Using HIF-1α inhibitor and prostaglandin receptor antagonists we demonstrated crucial role of these factor in functional alteration in TAMs. HIF-1α inhibition and also by prostaglandin receptor inhibition reduced signature pro-inflammatory gene expression, migration of macrophages and T cell suppression capacity of TAMs. We also demonstrated that PGE2 can induce HIF-1α activation in relatively less hypoxic microenvironment during early stages of tumor. CONCLUSION: Altogether, these findings strongly suggest link between prostaglandin mediated early HIF-1α activation and subsequent hypoxia induced HIF-1α activation that further enhances prostaglandin synthesis driving the recruitment and functional alteration of tumor site macrophages.


Assuntos
Carcinoma de Ehrlich/patologia , Dinoprostona/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/patologia , Sarcoma 180/patologia , Animais , Carcinoma de Ehrlich/imunologia , Movimento Celular , Progressão da Doença , Inflamação/imunologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Sarcoma 180/imunologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologia
15.
Biochem Biophys Res Commun ; 502(2): 232-237, 2018 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-29792860

RESUMO

Diphenyleneiodonium (DPI) and N-acetyl-l-cysteine (NAC), two widely used anti-oxidants, were employed to evaluate the role of oxidative stress in Japanese encephalitis virus (JEV) induced autophagy, stress responses and replication. DPI and NAC exerted opposite effects on ROS levels in JEV infected mouse neuronal cells (Neuro2a), mouse embryonic fibroblasts (MEFs) and human epithelial cells (HeLa). While NAC effectively quenched ROS, DPI enhanced ROS levels, suggesting that DPI induces oxidative stress in JEV infected cells. DPI treatment of JEV infected Neuro2a cells further blocked autophagy induction and activation of all three arms of the ER stress pathway, and, inhibited virus particle release. Autophagy induction in JEV infection has been previously shown to be linked to the activation of XBP1 and ATF6 ER stress sensors. Our data suggests that DPI mediated block of autophagy is a result of inhibition of ER stress responses and is not associated with an anti-oxidative effect. Since DPI has a wide inhibitory potential for all Flavin dependent enzymes, it is likely that the signalling pathways for ER stress and autophagy during JEV infection are modulated by DPI sensitive enzymes.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/efeitos dos fármacos , Oniocompostos/farmacologia , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Autofagia/efeitos dos fármacos , Células Cultivadas , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Suínos , Replicação Viral/efeitos dos fármacos
16.
Sci Rep ; 5: 17794, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26634309

RESUMO

Flavivirus infection causes host cell death by initiation of an unfolded protein response (UPR). UPR is initiated following activation of three ER-membrane resident sensors, PERK, IRE1α and ATF6, which are otherwise kept inactive through association with the ER-chaperone GRP78. Activation precedes cellular and molecular changes that act to restore homeostasis but might eventually initiate apoptosis. These changes involve influencing function of multiple genes by either transcriptional or post-transcriptional or post-translational mechanisms. Transcriptional control includes expression of transcription factor cascades, which influence cognate gene expression. Malat1 is a long non-coding RNA which is over-expressed in many human oncogenic tissues and regulates cell cycle and survival. In this report, for the first time we show activation of Malat1 following infection by two flaviviruses, both of which activate the UPR in host cells. The temporal kinetics of expression was restricted to later time points. Further, Malat1 was also activated by pharmacological inducer of UPR, to a similar degree. Using drugs that specifically inhibit or activate the PERK or IRE1α sensors, we demonstrate that signalling through the PERK axis activates this expression, through a transcriptional mechanism. To our knowledge, this is the first report of an UPR pathway regulating the expression of an lncRNA.


Assuntos
Apoptose/genética , Endorribonucleases/genética , Infecções por Flavivirus/genética , Proteínas Serina-Treonina Quinases/genética , RNA Longo não Codificante/biossíntese , eIF-2 Quinase/genética , Fator 6 Ativador da Transcrição/genética , Retículo Endoplasmático/genética , Retículo Endoplasmático/patologia , Chaperona BiP do Retículo Endoplasmático , Endorribonucleases/antagonistas & inibidores , Flavivirus/genética , Flavivirus/patogenicidade , Infecções por Flavivirus/patologia , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , RNA Longo não Codificante/genética , Transdução de Sinais , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Resposta a Proteínas não Dobradas/genética , eIF-2 Quinase/antagonistas & inibidores
17.
BMC Cancer ; 14: 567, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25098498

RESUMO

BACKGROUND: Increasingly, the role of chronic inflammation and its mediators in tumor generation and progression is gaining importance in the field of cancer research. In this context, candidature of non steroidal anti-inflammatory drugs (NSAIDs) as potential anti-tumor therapeutic agent is being evaluated globally. In the present study we have evaluated the anti-cancer effect of a series of newly synthesized naproxen derivatives on human breast cancer cell lines. METHODS: MCF-7 (poorly invasive) and MDA-MB-231 (highly invasive) cells were treated with different concentrations of naproxen sodium and its derivatives in vitro, and the underlying mechanism of action was monitored by employing studies related to induction of apoptosis, activation of caspases, cell-cycle progression, synthesis of PGE2 and cellular migration. RESULTS: After a preliminary screening using MCF-7 and MDA-MB-231 cells, it was evident that naproxen derivative 4 has a better killing property compared to its parent compound naproxen sodium (NS). On further investigation, it was apparent that the observed growth inhibitory activity on MDA-MB-231 cells after treatment with 4, was not due to cell cycle arrest but due to an early induction of apoptosis and subsequent induction of caspases 3 and 9. Derivative 4 could also inhibit COX activity in MDA-MB-231 cells as evidenced by reduction in prostaglandin E2 secretion. Moreover, 4 was capable of delaying the overall migration rate of MDA-MB-231 cells in vitro. CONCLUSION: In this study we report that a naproxen-derivative (4) has powerful anti-inflammatory and anti-tumor properties as it induces appreciable amount of apoptosis in breast cancer cell line, and can also delay migration of cancer cells (MDA-MB-231) which would in turn delay cancer cell invasion and formation of secondary tumours in primary breast cancer patients. Thus, we propose that 4 is worthy of further investigation due to its potential as a therapeutic agent in anti-tumor treatment regimen.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Neoplasias da Mama/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Naproxeno/análogos & derivados , Naproxeno/farmacologia , Animais , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos
18.
J Gen Virol ; 95(Pt 1): 71-79, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24114795

RESUMO

Japanese encephalitis virus (JEV) infection-induced encephalitis causes extensive death or long-term neurological damage, especially among children, in south and south-east Asia. Infection of mammalian cells has shown induction of an unfolded protein response (UPR), presumably leading to programmed cell death or apoptosis of the host cells. UPR, a cellular response to accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) lumen, is initiated by three ER-lumen-resident sensors (PERK, IRE1 and ATF6), and involves transcriptional and translational regulation of the expression of several genes. The sensor IRE1 possesses an intrinsic RNase activity, activated through homo-dimerization and autophosphorylation during UPR. Activated IRE1 performs cytoplasmic cleavage of Xbp1u transcripts, thus facilitating synthesis of XBP1S transcription factor, in addition to cleavage of a cohort of cellular transcripts, the later initiating the regulated IRE1-dependent decay (RIDD) pathway. In this study, we report the initiation of the RIDD pathway in JEV-infected mouse neuroblastoma cells (Neuro2a) and its effect on viral infection. Activation of the RIDD pathway led to degradation of known mouse cell target transcripts without showing any effect on JEV RNA despite the fact that both when biochemically purified showed significant enrichment in ER membrane-enriched fractions. Additionally, inhibition of the IRE1 RNase activity by STF083010, a specific drug, diminished viral protein levels and reduced the titre of the virus produced from infected Neuro2a cells. The results present evidence for the first report of a beneficial effect of RIDD activation on the viral life cycle.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/fisiologia , Encefalite Japonesa/enzimologia , Resposta a Proteínas não Dobradas , Replicação Viral , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/genética , Encefalite Japonesa/metabolismo , Encefalite Japonesa/virologia , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição de Fator Regulador X , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína 1 de Ligação a X-Box
19.
Immunity ; 39(6): 1057-69, 2013 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-24315995

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the authors. This study provided an explanation for why loss of FoxP3 in inducible regulatory T cells results in reduced expression of interleukin (IL)-10 despite the absence of FoxP3 binding sites in the IL-10 promoter. STAT3 binding sites do exist in the promoter, and evidence for a direct molecular interaction between FoxP3 and STAT3 proteins was provided as an explanation of the effect of loss of FoxP3. As supporting evidence, we reported modeling of a structural interaction between these two transcription factors in Figure 4D. As the N-terminal region of FoxP3, which consists of the Exon-2 region, had not been solved at structural resolution, we mistakenly used what we deduced to be a FoxP3 related transcription factor, NFAT, in the modeling. The model depicted in Figure 4D therefore did not represent a putative interaction between FoxP3 and STAT3 as labeled, but rather a putative interaction between NFAT and STAT3. Given the incorrect labeling of Figure 4D, the lack of documentation in the paper describing exactly how the modeling was performed, the lack of evidence shown in the paper for the choice of NFAT as the modeling partner, and the limited supporting evidence for a cooperative interaction between FoxP3 and STAT3, the editors have concluded with the corresponding author that the appropriate course of action is to retract the paper. We apologize for any confusion and inconvenience caused to readers.


Assuntos
Neoplasias da Mama/fisiopatologia , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Modelos Moleculares , Fatores de Transcrição
20.
Front Biosci (Schol Ed) ; 4(1): 335-55, 2012 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-22202064

RESUMO

Tumors are multifaceted; in fact, numerous things happen in synchrony to enable tumor promotion and progression. Any type of cancer is associated with the modification of 300-500 normal genes and characterized by the deregulation of cell signaling pathways at multiple steps leading to cancer phenotype. Thus a proper management of tumorigenesis requires the development of multi-targeted therapies. Several adverse effects associated with present day cancer therapies and the thirsts for multi-targeted safe anticancer drug instigate the use of natural polyphenol, curcumin. It appears to involve a blend of anti-carcinogenic, pro-apoptotic, anti-angiogenic, anti-metastatic, immunomodulatory and antioxidant activities. Also the molecular mechanisms implicated for the pleotropic activities of curcumin are diverse and seem to involve a combination of cell signaling pathways at multiple levels of tumorigenesis. Being a potent scavenger of reactive oxygen species, curcumin also ameliorates systemic toxicity in tumor-bearer. Taken together, by placing particular emphasis on molecular basis of tumor promotion and progression this review summarizes the anti-cancer properties of curcumin that may be exploited for successful clinical cancer prevention.


Assuntos
Curcumina/farmacologia , Curcumina/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Animais , Anticarcinógenos/farmacologia , Anticarcinógenos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Espécies Reativas de Oxigênio/metabolismo
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