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1.
Mol Diagn Ther ; 28(1): 69-86, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37907826

RESUMO

Immunotherapy for colorectal cancer (CRC) is limited to patients with advanced disease who have already undergone first-line chemotherapy and whose tumors exhibit microsatellite instability. Novel technical strategies are required to enhance therapeutic options and achieve a more robust immunological response. Therefore, exploring gene analysis and manipulation at the molecular level can further accelerate the development of advanced technologies to address these challenges. The emergence of advanced genome editing technology, particularly of clustered, regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein (Cas) 9, holds promise in expanding the boundaries of cancer immunotherapy. In this manuscript, we provide a comprehensive review of the applications and perspectives of CRISPR technology in improving the design, generation, and efficiency of current immunotherapies, focusing on solid tumors such as colorectal cancer, where these approaches have not been as successful as in hematological conditions.


Assuntos
Sistemas CRISPR-Cas , Neoplasias Colorretais , Humanos , Sistemas CRISPR-Cas/genética , Edição de Genes , Imunoterapia , Terapia Genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia
2.
Eur J Immunol ; 53(5): e2250128, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36785881

RESUMO

Signal transducer and activator of transcription 6 (STAT6) promotes tumorigenesis by decreasing the Forkhead box P3+ (Foxp3+) cell frequency allowing for the infiltration of inflammatory cells during the early stages of colitis-associated cancer (CAC). In this study, we dissected the role of STAT6 in the generation of inducible in vitro regulatory T cells (iTregs) and peripheral in vivo Tregs (pTregs) under inflammatory conditions. In in vitro assays, when STAT6 was lacking, iTregs preserved a stable phenotype and expressed high levels of Foxp3 and CD25 during long expansion periods, even in the presence of IL-6. This effect was associated with increased in vitro suppressive ability, over-expression of programmed death-1 (PD-1), CTLA-4, and Foxp3, and decreased IFN-γ expression. Furthermore, iTregs developed during STAT6 deficiency showed a higher demethylation status for the FOXP3 Treg-specific demethylated region (TSDR), coupled with lower DNA methyltransferase 1 (DNMT1) mRNA expression, suggesting that STAT6 may lead to Foxp3 silencing. Using a mouse model of CAC, the STAT6-/- pTregs expressed a more activated phenotype at the intestine, had higher suppressive capacity, and expressed more significant levels of PD-1 and latency-associated peptide of TGF-ß (LAP) associated with their ability to attenuate tumor development. These data suggest that STAT6 signaling impairs the induction, stability, and suppressive capacity of Tregs developed in vitro or in vivo during gut inflammation.


Assuntos
Receptor de Morte Celular Programada 1 , Linfócitos T Reguladores , Linfócitos T Reguladores/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fatores de Transcrição Forkhead/metabolismo
3.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36768437

RESUMO

In 2013, recognizing that Colorectal Cancer (CRC) is the second leading cause of death by cancer worldwide and that it was a neglected disease increasing rapidly in Mexico, the community of researchers at the Biomedicine Research Unit of the Facultad de Estudios Superiores Iztacala from the Universidad Nacional Autónoma de México (UNAM) established an intramural consortium that involves a multidisciplinary group of researchers, technicians, and postgraduate students to contribute to the understanding of this pathology in Mexico. This article is about the work developed by the Mexican Colorectal Cancer Research Consortium (MEX-CCRC): how the Consortium was created, its members, and its short- and long-term goals. Moreover, it is a narrative of the accomplishments of this project. Finally, we reflect on possible strategies against CRC in Mexico and contrast all the data presented with another international strategy to prevent and treat CRC. We believe that the Consortium's characteristics must be maintained to initiate a national strategy, and the reported data could be useful to establish future collaborations with other countries in Latin America and the world.


Assuntos
Neoplasias Colorretais , Estudantes , Humanos , México , Estudos Interdisciplinares , Terapias em Estudo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/terapia
4.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299314

RESUMO

Signal transducer and activator of transcription 1 (STAT1) acts as a tumor suppressor molecule in colitis-associated colorectal cancer (CAC), particularly during the very early stages, modulating immune responses and controlling mechanisms such as apoptosis and cell proliferation. Previously, using an experimental model of CAC, we reported increased intestinal cell proliferation and faster tumor development, which were consistent with more signs of disease and damage, and reduced survival in STAT1-/- mice, compared with WT counterparts. However, the mechanisms through which STAT1 might prevent colorectal cancer progression preceded by chronic inflammation are still unclear. Here, we demonstrate that increased tumorigenicity related to STAT1 deficiency could be suppressed by IL-17 neutralization. The blockade of IL-17 in STAT1-/- mice reduced the accumulation of CD11b+Ly6ClowLy6G+ cells resembling granulocytic myeloid-derived suppressor cells (MDSCs) in both spleen and circulation. Additionally, IL-17 blockade reduced the recruitment of neutrophils into intestinal tissue, the expression and production of inflammatory cytokines, and the expression of intestinal STAT3. In addition, the anti-IL-17 treatment also reduced the expression of Arginase-1 and inducible nitric oxide synthase (iNOS) in the colon, both associated with the main suppressive activity of MDSCs. Thus, a lack of STAT1 signaling induces a significant change in the colonic microenvironment that supports inflammation and tumor formation. Anti-IL-17 treatment throughout the initial stages of CAC related to STAT1 deficiency abrogates the tumor formation possibly caused by myeloid cells.


Assuntos
Neoplasias Associadas a Colite/etiologia , Granulócitos/patologia , Interleucina-17/fisiologia , Fator de Transcrição STAT1/fisiologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Neoplasias Associadas a Colite/patologia , Neoplasias Associadas a Colite/fisiopatologia , Progressão da Doença , Feminino , Granulócitos/imunologia , Interleucina-17/antagonistas & inibidores , Interleucina-17/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/patologia , Neoplasias Experimentais/etiologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/fisiopatologia , Fator de Transcrição STAT1/deficiência , Fator de Transcrição STAT1/genética , Microambiente Tumoral/imunologia
5.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919941

RESUMO

Inflammation is the main driver of the tumor initiation and progression in colitis-associated colorectal cancer (CAC). Recent findings have indicated that the signal transducer and activator of transcription 6 (STAT6) plays a fundamental role in the early stages of CAC, and STAT6 knockout (STAT6-/-) mice are highly resistant to CAC development. Regulatory T (Treg) cells play a major role in coordinating immunomodulation in cancer; however, the role of STAT6 in the induction and function of Treg cells is poorly understood. To clarify the contribution of STAT6 to CAC, STAT6-/- and wild type (WT) mice were subjected to an AOM/DSS regimen, and the frequency of peripheral and local Treg cells was determined during the progression of CAC. When STAT6 was lacking, a remarkable reduction in tumor growth was observed, which was associated with decreased inflammation and an increased number of CD4+CD25+Foxp3+ cells in the colon, circulation, and spleen, including an over-expression of TGF-beta, IL-10, and Foxp3, compared to WT mice, during the early stages of CAC development. Conversely, WT mice showed an inverse frequency of Treg cells compared with STAT6-/- mice, which was followed by intestinal tumor formation. Increased mucosal inflammation, histological damage, and tumorigenesis were restored to levels observed in WT mice when an early inhibition/depletion of Treg cells was performed in STAT6-/- mice. Thus, with STAT6 deficiency, an increased number of Treg cells induce resistance against tumorigenesis, arresting tumor-promoting inflammation. We reported a direct role of STAT6 in the induction and function of Treg cells during CAC development and suggest that STAT6 is a potential target for the modulation of immune response in colitis and CAC.


Assuntos
Neoplasias Associadas a Colite/genética , Neoplasias Colorretais/genética , Inflamação/genética , Fator de Transcrição STAT6/genética , Animais , Neoplasias Associadas a Colite/imunologia , Neoplasias Associadas a Colite/patologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/imunologia , Inflamação/patologia , Interleucina-10/genética , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta/genética
6.
Oncol Lett ; 20(1): 455-464, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32565970

RESUMO

Signal transducer and activator of transcription 6 (STAT6) is a member of the STAT family of proteins that serve key roles in the initiation of tumorigenesis and malignant transformation. STAT6 is highly expressed in several types of cancer, including breast, pancreatic, prostate and colorectal cancer. STAT6 transduces signals in response to the binding of interleukin (IL)-4 and IL-13 to their receptors and regulates the expression of genes involved in the immune response, cell survival, tumor proliferation and metastasis. Patients with colorectal cancer exhibit high STAT6 activity in the colonic epithelium, and STAT6 expression is associated with lower survival rates, lymph node metastasis, changes in the epithelial barrier function and alterations in the inflammatory response. A number of studies investigating experimental models and cancer cell lines have revealed that STAT6 is associated with tumor growth and development, as well as with increased invasion and metastasis, suggesting that STAT6 inhibition may serve as a novel therapeutic strategy in colon cancer. The present review summarizes the evidence with regard to the implications of STAT6 in cancer biology and the direct and indirect effects on colon tumor transformation. Furthermore, the current treatment strategies targeting the IL-4/IL-13/STAT6 axis in colon cancer are discussed.

7.
Int J Mol Sci ; 21(6)2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32244885

RESUMO

Colorectal cancer (CRC) is one of the most widespread and deadly types of neoplasia around the world, where the inflammatory microenvironment has critical importance in the process of tumor growth, metastasis, and drug resistance. Despite its limited effectiveness, 5-fluorouracil (5-FU) is the main drug utilized for CRC treatment. The combination of 5-FU with other agents modestly increases its effectiveness in patients. Here, we evaluated the anti-inflammatory Trimethylglycine and the Signal transducer and activator of transcription (STAT6) inhibitor AS1517499, as possible adjuvants to 5-FU in already established cancers, using a model of colitis-associated colon cancer (CAC). We found that these adjuvant therapies induced a remarkable reduction of tumor growth when administrated together with 5-FU, correlating with a reduction in STAT6-phosphorylation. This reduction upgraded the effect of 5-FU by increasing both levels of apoptosis and markers of cell adhesion such as E-cadherin, whereas decreased epithelial-mesenchymal transition markers were associated with aggressive phenotypes and drug resistance, such as ß-catenin nuclear translocation and Zinc finger protein SNAI1 (SNAI1). Additionally, Il-10, Tgf-ß, and Il-17a, critical pro-tumorigenic cytokines, were downmodulated in the colon by these adjuvant therapies. In vitro assays on human colon cancer cells showed that Trimethylglycine also reduced STAT6-phosphorylation. Our study is relatively unique in focusing on the effects of the combined administration of AS1517499 and Trimethylglycine together with 5-FU on already established CAC which synergizes to markedly reduce the colon tumor load. Together, these data point to STAT6 as a valuable target for adjuvant therapy in colon cancer.


Assuntos
Adjuvantes Farmacêuticos/uso terapêutico , Carcinogênese/patologia , Colite/complicações , Neoplasias do Colo/tratamento farmacológico , Fluoruracila/uso terapêutico , Glicina/uso terapêutico , Pirimidinas/uso terapêutico , Fator de Transcrição STAT6/metabolismo , Adjuvantes Farmacêuticos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caderinas/metabolismo , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Colite/patologia , Neoplasias do Colo/etiologia , Neoplasias do Colo/patologia , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Fluoruracila/farmacologia , Glicina/farmacologia , Humanos , Inflamação/patologia , Camundongos Endogâmicos BALB C , Monócitos/metabolismo , Fosforilação/efeitos dos fármacos , Pirimidinas/farmacologia , beta Catenina/metabolismo
8.
Immunotherapy ; 12(1): 9-24, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914828

RESUMO

Aim: Glucose intolerance associates with M1/M2 macrophage unbalance. We thus wanted to examine the effect of M2 macrophage administration on mouse model of glucose intolerance. Materials & methods: C57BL/6 mice fed a high-fat diet (HFD) for 12 weeks and then received thrice 20 mg/kg streptozotocin (HFD-GI). Bone marrow-derived stem cells were collected from donor mice and differentiated/activated into M2 macrophages for intraperitoneal administration into HFD-GI mice. Results: M2 macrophage treatment abolished glucose intolerance independently of obesity. M2 macrophage administration increased IL-10 in visceral adipose tissue and serum, but showed no effect on serum insulin. While nitric oxide synthase-2 and arginase-1 remained unaltered, M2 macrophage treatment restored AKT phosphorylation in visceral adipose tissue. Conclusion: M2 macrophage treatment abolishes glucose intolerance by increasing IL-10 and phosphorylated AKT.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Imunoterapia/métodos , Interleucina-10/metabolismo , Macrófagos/imunologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Diabetes Mellitus Tipo 2/imunologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Intolerância à Glucose , Humanos , Resistência à Insulina , Interleucina-10/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Estreptozocina , Células Th2/imunologia
9.
Int J Cancer ; 145(11): 3126-3139, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31407335

RESUMO

Inflammation is currently considered a hallmark of cancer and plays a decisive role in different stages of tumorigenesis, including initiation, promotion, progression, metastasis and resistance to antitumor therapies. Colorectal cancer is a disease widely associated with local chronic inflammation. Additionally, extrinsic factors such as infection may beneficially or detrimentally alter cancer progression. Several reports have noted the ability of various parasitic infections to modulate cancer development, favoring tumor progression in many cases and inhibiting tumorigenesis in others. The aim of our study was to determine the effects of excreted/secreted products of the helminth Taenia crassiceps (TcES) as a treatment in a murine model of colitis-associated colon cancer (CAC). Here, we found that after inducing CAC, treatment with TcES was able to reduce inflammatory cytokines such as IL-1ß, TNF-α, IL-33 and IL-17 and significantly attenuate colon tumorigenesis. This effect was associated with the inhibition of signal transducer and activator of transcription 3 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) phosphorylation. Furthermore, we determined that TcES interfered with LPS-induced NF-κB p65 activation in human colonic epithelial cell lines in a Raf-1 proto-oncogene-dependent manner. Moreover, in three-dimensional cultures, TcES promoted reorganization of the actin cytoskeleton, altering cell morphology and forming colonospheres, features associated with a low grade of aggressiveness. Our study demonstrates a remarkable effect of helminth-derived molecules on suppressing ongoing colorectal cancer by downregulating proinflammatory and protumorigenic signaling pathways.


Assuntos
Anti-Inflamatórios/administração & dosagem , Azoximetano/efeitos adversos , Colite/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Proteínas de Helminto/administração & dosagem , Taenia/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colite/induzido quimicamente , Colite/complicações , Neoplasias do Colo/etiologia , Modelos Animais de Doenças , Feminino , Proteínas de Helminto/farmacologia , Humanos , Interleucina-1beta/metabolismo , Interleucina-33/metabolismo , Camundongos , NF-kappa B/metabolismo , Fosforilação , Proto-Oncogene Mas , Fator de Transcrição STAT3/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Cancers (Basel) ; 10(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235866

RESUMO

Signal transducer and activator of transcription 1 (STAT1) is part of the Janus kinase (JAK/STAT) signaling pathway that controls critical events in intestinal immune function related to innate and adaptive immunity. Recent studies have implicated STAT1 in tumor⁻stroma interactions, and its expression and activity are perturbed during colon cancer. However, the role of STAT1 during the initiation of inflammation-associated cancer is not clearly understood. To determine the role of STAT1 in colitis-associated colorectal cancer (CAC), we analyzed the tumor development and kinetics of cell recruitment in wild-type WT or STAT1-/- mice treated with azoxymethane (AOM) and dextran sodium sulfate (DSS). Following CAC induction, STAT1-/- mice displayed an accelerated appearance of inflammation and tumor formation, and increased damage and scores on the disease activity index (DAI) as early as 20 days after AOM-DSS exposure compared to their WT counterparts. STAT1-/- mice showed elevated colonic epithelial cell proliferation in early stages of injury-induced tumor formation and decreased apoptosis in advanced tumors with over-expression of the anti-apoptotic protein Bcl2 at the colon. STAT1-/- mice showed increased accumulation of Ly6G⁺Ly6C-CD11b⁺ cells in the spleen at 20 days of CAC development with concomitant increases in the production of IL-17A, IL-17F, and IL-22 cytokines compared to WT mice. Our findings suggest that STAT1 plays a role as a tumor suppressor molecule in inflammation-associated carcinogenesis, particularly during the very early stages of CAC initiation, modulating immune responses as well as controlling mechanisms such as apoptosis and cell proliferation.

12.
J Cancer ; 9(2): 239-249, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344269

RESUMO

Colorectal cancer (CRC) is the second most commonly diagnosed cancer in women and the third in men in North America and Europe. CRC is associated with inflammatory responses in which intestinal pathology is caused by different cell populations including a T cell dysregulation that concludes in an imbalance between activated T (Tact) and regulatory T (Treg) cells. Treg cells are CD4+Foxp3+ cells that actively suppress pathological and physiological immune responses, contributing to the maintenance of immune homeostasis. A tumor-promoting function for Treg cells has been suggested in CRC, but the kinetics of Treg cells during CRC development are poorly known. Therefore, using a mouse model of colitis-associated colon cancer (CAC) induced by azoxymethane and dextran sodium sulfate, we observed the dynamic and differential kinetics of Treg cells in blood, spleen and mesenteric lymph nodes (MLNs) as CAC progresses, highlighting a significant reduction in Treg cells in blood and spleen during early CAC development, whereas increasing percentages of Treg cells were detected in late stages in MLNs. Interestingly, when Treg cells were decreased, Tact cells were increased and vice versa. Treg cells from late stages of CAC displayed an activated phenotype by expressing PD1, CD127 and Tim-3, suggesting an increased suppressive capacity. Suppression assays showed that T-CD4+ and T-CD8+ cells were suppressed more efficiently by MLN Treg cells from CAC animals. Finally, an antibody-mediated reduction in Treg cells during early CAC development resulted in a better prognostic value, because animals showed a reduction in tumor progression associated with an increased percentage of activated CD4+CD25+Foxp3- and CD8+CD25+ T cells in MLNs, suggesting that Treg cells suppress T cell activation at early steps during CAC development.

13.
Cancer Immunol Res ; 5(5): 385-396, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28385737

RESUMO

Colitis-associated colon cancer (CAC) is one of the most common malignant neoplasms and a leading cause of death. The immunologic factors associated with CAC development are not completely understood. Signal transducer and activator of transcription 6 (STAT6) is part of an important signaling pathway for modulating intestinal immune function and homeostasis. However, the role of STAT6 in colon cancer progression is unclear. Following CAC induction in wild-type (WT) and STAT6-deficient mice (STAT6-/-), we found that 70% of STAT6-/- mice were tumor-free after 8 weeks, whereas 100% of WT mice developed tumors. STAT6-/- mice displayed fewer and smaller colorectal tumors than WT mice; this reduced tumorigenicity was associated with decreased proliferation and increased apoptosis in the colonic mucosa in the early steps of tumor progression. STAT6-/- mice also exhibited reduced inflammation, diminished concentrations COX2 and nuclear ß-catenin protein in the colon, and decreased mRNA expression of IL17A and TNFα, but increased IL10 expression when compared with WT mice. Impaired mucosal expression of CCL9, CCL25, and CXCR2 was also observed. In addition, the number of circulating CD11b+Ly6ChiCCR2+ monocytes and CD11b+Ly6ClowLy6G+ granulocytes was both decreased in a STAT6-dependent manner. Finally, WT mice receiving a STAT6 inhibitor in vivo confirmed a significant reduction in tumor load as well as less intense signs of CAC. Our results demonstrate that STAT6 is critical in the early steps of CAC development for modulating inflammatory responses and controlling cell recruitment and proliferation. Thus, STAT6 may represent a promising target for CAC treatment. Cancer Immunol Res; 5(5); 385-96. ©2017 AACR.


Assuntos
Colite/complicações , Neoplasias do Colo/etiologia , Neoplasias do Colo/prevenção & controle , Fator de Transcrição STAT6/deficiência , Animais , Apoptose , Azoximetano , Proliferação de Células , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Sulfato de Dextrana , Feminino , Inflamação , Camundongos Endogâmicos BALB C , Camundongos Knockout , RNA Mensageiro/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo , beta Catenina/metabolismo
14.
Mem. Inst. Oswaldo Cruz ; 111(12): 757-764, Dec. 2016. graf
Artigo em Inglês | LILACS | ID: biblio-829258

RESUMO

We evaluated the effects of a non-hepatotropic parasite infection (Taenia crassiceps) on the outcome of acetaminophen-induced acute liver failure in mice. Uninfected and T. crassiceps infected mice orally received either 300 mg/kg acetaminophen or water as vehicle (n = 5 per group). Survival analysis, hepatocyte necrosis, alanine aminotransferase (ALT) levels, CYP2E1 protein, interleukin (IL-) 5, and IL-6 were assessed for all groups. All infected mice died within 16 h after exposure to acetaminophen (Tc+APAP group), whereas only one-third of uninfected animals exposed to acetaminophen (APAP group) died. Uninfected (Control group) and infected (Tc group) mice that received the vehicle showed no liver damage. Tc+APAP mice exhibited massive liver necrosis characterised by marked balloning degeneration of hepatocytes and higher serum ALT compared to Control, Tc, and APAP animals. Liver tissue from Tc+APAP mice also displayed increased expression of CYP2E1 protein and higher mRNA and protein levels of IL-5 and IL-6 compared to the other groups. These findings suggest that non-hepatotropic parasite infections may increase mortality following acute liver failure by promoting hepatocyte necrosis via IL-5 and IL-6-dependent CYP2E1 overproduction. This study identifies new potential risk factors associated with severe acute liver failure in patients.


Assuntos
Animais , Feminino , Acetaminofen , Analgésicos não Narcóticos , Falência Hepática Aguda , Teníase/parasitologia , Acetaminofen/administração & dosagem , Alanina Transaminase/sangue , Analgésicos não Narcóticos/administração & dosagem , Biomarcadores/sangue , Citocromo P-450 CYP2E1/biossíntese , Citocromo P-450 CYP2E1/sangue , Modelos Animais de Doenças , Hepatócitos/parasitologia , Hepatócitos/patologia , Interleucina-5/sangue , Interleucina-6/sangue , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/mortalidade , Falência Hepática Aguda/parasitologia , Falência Hepática Aguda/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Teníase/patologia
15.
Mem Inst Oswaldo Cruz ; 111(12): 757-764, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27812602

RESUMO

We evaluated the effects of a non-hepatotropic parasite infection (Taenia crassiceps) on the outcome of acetaminophen-induced acute liver failure in mice. Uninfected and T. crassiceps infected mice orally received either 300 mg/kg acetaminophen or water as vehicle (n = 5 per group). Survival analysis, hepatocyte necrosis, alanine aminotransferase (ALT) levels, CYP2E1 protein, interleukin (IL-) 5, and IL-6 were assessed for all groups. All infected mice died within 16 h after exposure to acetaminophen (Tc+APAP group), whereas only one-third of uninfected animals exposed to acetaminophen (APAP group) died. Uninfected (Control group) and infected (Tc group) mice that received the vehicle showed no liver damage. Tc+APAP mice exhibited massive liver necrosis characterised by marked balloning degeneration of hepatocytes and higher serum ALT compared to Control, Tc, and APAP animals. Liver tissue from Tc+APAP mice also displayed increased expression of CYP2E1 protein and higher mRNA and protein levels of IL-5 and IL-6 compared to the other groups. These findings suggest that non-hepatotropic parasite infections may increase mortality following acute liver failure by promoting hepatocyte necrosis via IL-5 and IL-6-dependent CYP2E1 overproduction. This study identifies new potential risk factors associated with severe acute liver failure in patients.


Assuntos
Acetaminofen , Analgésicos não Narcóticos , Falência Hepática Aguda , Teníase/parasitologia , Acetaminofen/administração & dosagem , Alanina Transaminase/sangue , Analgésicos não Narcóticos/administração & dosagem , Animais , Biomarcadores/sangue , Citocromo P-450 CYP2E1/biossíntese , Citocromo P-450 CYP2E1/sangue , Modelos Animais de Doenças , Feminino , Hepatócitos/parasitologia , Hepatócitos/patologia , Interleucina-5/sangue , Interleucina-6/sangue , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/mortalidade , Falência Hepática Aguda/parasitologia , Falência Hepática Aguda/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Teníase/patologia
16.
J Cancer ; 7(12): 1632-1644, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27698900

RESUMO

Colorectal cancer (CRC) is an important health issue worldwide, accounting for the third place of cancer incidence. Chronic inflammation, as seen in Crohn's disease and ulcerative colitis, is the most important risk factor for developing CRC, as it favours neoplastic transformation by enhancing epithelial cell turnover in the colonic mucosa. Treatments for CRC need to be improved; currently they are not specific and have several secondary effects in patients. The main objective of this work was to evaluate a new therapeutic strategy against a colitis-related colorectal cancer in vivo and in vitro by targeting mTOR-signaling and lactate dehydrogenase A. Together, these mechanisms directly affect tumor energetics. In this study we evaluated a better and more efficient triple therapy against a chronic inflammation-associated CRC in vivo and in vitro. After the development of tumors, mice were treated intraperitoneally during a forty-day period with single drugs or different combinations of Metformin, Sodium Oxamate and Doxorubicin. Targeted inhibition of the mTOR pathway, lactate dehydrogenase A and the concurrent use of Doxorubicin (called in this work as triple therapy), leaded to a notable reduction in the number and size of tumors in mice, and, a significant pro-inflammatory cytokines reduction Besides, we showed that treated cells were induced to early autophagy, and apoptosis cell death. Our results represent a novel and robust therapeutic strategy for overcoming CRC by means of targeting central molecular pathways in cancer by the combination of Metformin, Oxamate, and Doxorubicin leading to a rapid tumor growth inhibition and a dramatic colorectal crypt restoration. Besides, drug combination resulted in a notable reduction of anti-inflammatory cytokines.

17.
Food Chem Toxicol ; 93: 20-31, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27117919

RESUMO

Colorectal cancer is the fourth worldwide cause of death and even if some dietary habits are consider risk factors, the contribution of food additives including foodgrade titanium dioxide (TiO2), designated as E171, has been poorly investigated. We hypothesized that oral E171 intake could have impact on the enhancement of colorectal tumor formation and we aimed to investigate if E171 administration could enhance tumor formation in a colitis associated cancer (CAC) model. BALB/c male mice were grouped as follows: a) control, b) E171, c) CAC and d) CAC + E171 group (n = 6). E171 used in this study formed agglomerates of 300 nm in water. E171 intragastric administration (5 mg/kg body weight/5 days/10 weeks) was unable to induce tumor formation but dysplastic alterations were observed in the distal colon but enhanced the tumor formation in distal colon (CAC + E171 group) measured by tumor progression markers. Some E171 particles were internalized in colonic cells of the E171 and CAC + E171 groups and both groups showed a decrease in goblet cells in the distal colon. However the CAC + E171 group showed a higher decrease of these cells that act as protection barrier in colon. These results suggest that E171 could worsen pre-existent intestinal diseases.


Assuntos
Colite/complicações , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Aditivos Alimentares/toxicidade , Células Caliciformes/patologia , Titânio/toxicidade , Animais , Células Cultivadas , Colite/tratamento farmacológico , Neoplasias Colorretais/induzido quimicamente , Células Caliciformes/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
18.
Biomed Res Int ; 2015: 563425, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090422

RESUMO

Chronic inflammation of the intestinal mucosa is characteristic of inflammatory bowel diseases such as ulcerative colitis and Crohn's disease. Helminth parasites have developed immunomodulatory strategies that may impact the outcome of several inflammatory diseases. Therefore, we investigated whether Taenia crassiceps infection is able to decrease the inflammatory effects of dextran sulfate sodium- (DSS-) induced ulcerative colitis in BALB/c and C57BL/6 mice. Preinfection significantly reduced the manifestations of DSS-induced colitis, as weight loss and shortened colon length, and decreased the disease activity index independently of the genetic background of the mice. Taenia infection decreased systemic levels of proinflammatory cytokines while increasing levels of IL-4 and IL-10, and the inflammatory infiltrate into the colon was also markedly reduced. RT-PCR assays from colon showed that T. crassiceps-infected mice displayed increased expression of Arginase-1 but decreased expression of iNOS compared to DSS-treated uninfected mice. The percentages of T regulatory cells were not increased. The adoptive transfer of alternatively activated macrophages (AAMФs) from infected mice into mice with DSS-induced colitis reduced the severity of colon inflammation. Administration of indomethacin abrogated the anticolitic effect of Taenia. Thus, T. crassiceps infection limits the pathology of ulcerative colitis by suppressing inflammatory responses mechanistically associated with AAMФs and prostaglandins.


Assuntos
Colite Ulcerativa/parasitologia , Doença de Crohn/parasitologia , Inflamação/parasitologia , Prostaglandinas/biossíntese , Animais , Arginase , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/genética , Doença de Crohn/induzido quimicamente , Doença de Crohn/genética , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Interleucina-10/biossíntese , Interleucina-4/biossíntese , Mucosa Intestinal/parasitologia , Mucosa Intestinal/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Óxido Nítrico Sintase Tipo II/biossíntese , Prostaglandinas/metabolismo , Taenia/patogenicidade , Teníase/complicações , Teníase/parasitologia
19.
Mediators Inflamm ; 2015: 493409, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25944984

RESUMO

Obstructive sleep apnea (OSA) has been related to elevation of inflammatory cytokines and development of insulin resistance in morbidly obese (MO) subjects. However, it is still unclear whether the systemic concentration of anti-inflammatory mediators is also affected in MO subjects directly related to the severity of OSA and level of insulin resistance. Normal weight and MO subjects were subjected to overnight polysomnography in order to establish the severity of OSA, according to the apnea-hypopnea index (AHI). Blood samples were obtained for estimation of total cholesterol and triglycerides, insulin, glucose, insulin resistance, tumor necrosis factor alpha (TNF-α), interleukin 12 (IL12), and interleukin 10 (IL-10). Serum levels of IL-10 were significantly lower in MO subjects with OSA than in MO and control individuals without OSA. Besides being inversely associated with serum TNF-α and IL-12, decreased IL-10 levels were significantly related to increased AHI, hyperinsulinemia, and insulin resistance. Serum IL-10 is significantly reduced in morbidly obese subjects with severe OSA while also showing a clear relationship with a state of hyperinsulinemia and insulin resistance probably regardless of obesity in the present sample. It may be of potential clinical interest to identify the stimulatory mechanisms of IL-10 in obese individuals with OSA.


Assuntos
Regulação da Expressão Gênica , Resistência à Insulina , Interleucina-10/sangue , Obesidade Mórbida/imunologia , Apneia Obstrutiva do Sono/metabolismo , Adulto , Antropometria , Índice de Massa Corporal , Estudos de Casos e Controles , Colesterol/metabolismo , Citocinas/metabolismo , Feminino , Humanos , Hiperinsulinismo , Insulina/metabolismo , Interleucina-10/metabolismo , Subunidade p35 da Interleucina-12/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/metabolismo , Polissonografia , Síndromes da Apneia do Sono/metabolismo , Inquéritos e Questionários , Triglicerídeos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
20.
Int J Biol Sci ; 10(9): 948-56, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25210492

RESUMO

Colitis-associated colorectal cancer (CAC) is one of the most common cancers and is closely related to chronic or deregulated inflammation. Helminthic infections can modulate inflammatory responses in some diseases, but their immunomodulatory role during cancer development remains completely unknown. We have analyzed the role of Taenia crassiceps-induced anti-inflammatory response in determining the outcome of CAC. We show that extraintestinal T. crassiceps infection in CAC mice inhibited colonic inflammatory responses and tumor formation and prevented goblet cell loss. There was also increased expression of IL-4 and alternatively activated macrophages markers in colonic tissue and negative immunomodulation of pro-inflammatory cytokine expression. In addition, T. crassiceps infection prevented the upregulation of ß-catenin and CXCR2 expression observed in the CAC mice, which are both markers associated with CAC-tumorigenesis, and reduced the numbers of circulating and colonic CD11b(+)Ly6C(hi)CCR2(+) monocytes. Thus, immunomodulatory activities induced by helminth infections may have a role in the progression of CAC.


Assuntos
Colite/complicações , Neoplasias Colorretais/etiologia , Teníase/metabolismo , Animais , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/metabolismo , Sulfato de Dextrana/toxicidade , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Taenia
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