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1.
Rev. cuba. med. mil ; 53(1)mar. 2024.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1569899

RESUMO

La Dra. Raquel Pérez González, más conocida entre colegas, alumnos y compañeros de trabajo por "la profe Raquel", obtuvo el título de Medicina en el año 1976. Comenzó por vía directa la residencia de Radiología y obtuvo el título de especialista de primer grado en 1979. Se convirtió así, el Hospital Militar Central "Dr. Carlos J. Finlay", en la cuna de su formación profesional y en años posteriores, en la casa que la vio crecer, especialmente como maestra de numerosas generaciones de radiólogos e imagenólogos. Hoy reposan en el jardín del Departamento de Imagenología, parte de sus cenizas, custodiadas por el amor que fue capaz de cultivar. En el 2016, una paciente femenina de 60 años de edad, acudió a la consulta de gastroenterología, con dolor abdominal difuso. La radiografía de abdomen simple, anteroposterior, en posición acostado mostró, una imagen en "muela de cangrejo", visible al tomar el aire dentro del hemicolon transverso izquierdo, como contraste, el cual bordea por ese lado parcialmente, una opacidad de partes blandas, que se extiende desde el mesogastrio, hasta la fosa ilíaca derecha, donde se observa el signo del menisco. Los estudios de imágenes realizados, evidenciaron signos radiológicos típicos de invaginación por causa tumoral maligna. En varias ocasiones, la profesora Raquel utilizó la imagen de este caso, como pregunta en exámenes de promoción de residentes. La publicación de este caso constituye un homenaje a quien será siempre un paradigma de docente.


Dr. Raquel Pérez González, better known among colleagues, students and co-workers as "professor Raquel", obtained her degree in Medicine in 1976. She began her Radiology residency directly and obtained the title of first-class specialist degree in 1979. Thus, the Central Military Hospital "Dr. Carlos J. Finlay" is the cradle of her professional training and in later years, in her home where she saw her grow up, especially as a teacher to numerous generations of radiologists and imaging scientists. Today, part of her ashes rest in the garden of the Imaging Department, guarded by the love that she was able to cultivate. In 2016, a 60-year-old female patient attended the gastroenterology clinic with diffuse abdominal pain. The simple, anteroposterior abdominal x-ray, in the lying position, showed a "crab claw" image, visible when breathing into the left transverse hemicolon, as contrast, which partially borders on that side, a soft tissue opacity, which extends from the mesogastrium to the right iliac fossa, where the meniscus sign is observed. The imaging studies performed showed typical radiological signs of invagination due to malignant tumor. On several occasions, Professor Raquel used the image of this case as a question in resident promotion exams. The publication of this case constitutes a tribute to someone who will always be a paradigm of a teacher.


Assuntos
Humanos , Feminino , Radiologia/educação , Neoplasias do Colo/etiologia , Docentes/história , Intussuscepção/diagnóstico , Liderança
2.
Clin Transl Oncol ; 24(11): 2155-2165, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35761123

RESUMO

PURPOSE: Panitumumab plus FOLFOX (P-FOLFOX) is standard first-line treatment for RAS wild-type (WT) metastatic colorectal cancer. The value of panitumumab rechallenge is currently unknown. We assessed addition of panitumumab to FOLFIRI (P-FOLFIRI) beyond progression to P-FOLFOX in patients with no RAS mutations in liquid biopsy (LB). METHODS: In this randomized phase II trial, patients were assigned (3:2 ratio) to second-line P-FOLFIRI (arm A) or FOLFIRI alone (arm B). LB for circulating tumor DNA analysis was collected at study entry and at disease progression. Primary endpoint was 6-month progression-free survival. Two-stage Simon design required 85 patients to be included (EudraCT 2017-004519-38). RESULTS: Between February 2019 and November 2020, 49 patients were screened (16 RAS mutations in LB detected) and 31 included (18 assigned to arm A and 13 to arm B). The study was prematurely closed due to inadequate recruitment. Serious adverse events were more frequent in arm A (44% vs. 23%). Overall response rate was 33% (arm A) vs. 7.7% (arm B). Six-month progression-free survival rate was 66.7% (arm A) and 38.5% (arm B). Median progression-free survival was 11.0 months (arm A) and 4.0 months (arm B) (hazard ratio, 0.58). At disease progression, RAS or BRAF mutations in LB were found in 4/11 patients (36%) in arm A and 2/10 (20%) in arm B. CONCLUSIONS: The BEYOND study suggests a meaningful benefit of P-FOLFIRI beyond progression to P-FOLFOX in metastatic colorectal cancer patients with WT RAS status selected by LB. This strategy deserves further investigation.


Assuntos
DNA Tumoral Circulante , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/uso terapêutico , DNA Tumoral Circulante/genética , Neoplasias do Colo/etiologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Panitumumabe/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética
3.
Int J Mol Sci ; 22(20)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34681866

RESUMO

A close connection between inflammation and the risk of developing colon cancer has been suggested in the last few years. It has been estimated that patients diagnosed with some types of inflammatory bowel disease, such as ulcerative colitis or Crohn's disease, have up to a 30% increased risk of developing colon cancer. However, there is also evidence showing that the activation of anti-inflammatory pathways, such as the IL-4 receptor-mediated pathway, may favor the development of colon tumors. Using an experimental model of colitis-associated colon cancer (CAC), we found that the decrease in tumor development in global IL4Rα knockout mice (IL4RαKO) was apparently associated with an inflammatory response mediated by the infiltration of M1 macrophages (F480+TLR2+STAT1+) and iNOS expression in colon tissue. However, when we developed mice with a specific deletion of IL4Rα in macrophages (LysMcreIL4Rα-/lox mice) and subjected them to CAC, it was found that despite presenting a large infiltration of M1 macrophages into the colon, these mice were as susceptible to colon-tumorigenesis as WT mice. These data suggest that in the tumor microenvironment the absence of IL4Rα expression on macrophages, as well as the recruitment of M1 macrophages, may not be directly associated with resistance to developing colon tumors. Therefore, it is possible that IL4Rα expression in other cell types, such as colonic epithelial cells, could have an important role in promoting the development of colitis-associated colon tumorigenesis.


Assuntos
Colite/patologia , Neoplasias do Colo/patologia , Macrófagos/patologia , Receptores de Superfície Celular/genética , Animais , Neoplasias do Colo/etiologia , Neoplasias do Colo/genética , Citocinas/metabolismo , Feminino , Macrófagos/fisiologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Transgênicos , Neoplasias Experimentais , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Receptores de Superfície Celular/metabolismo , Macrófagos Associados a Tumor/patologia
4.
J Immunother Cancer ; 8(1)2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376720

RESUMO

BACKGROUND: Previous data have reported that the growth of established tumors may be facilitated by postsepsis disorder through changes in the microenvironment and immune dysfunction. However, the influence of postsepsis disorder in initial carcinogenesis remains elusive. METHODS: In the present work, the effect of postsepsis on inflammation-induced early carcinogenesis was evaluated in an experimental model of colitis-associated colorectal cancer (CAC). We also analyzed the frequency and role of intestinal T regulatory cells (Treg) in CAC carcinogenesis. RESULTS: The colitis grade and the tumor development rate were evaluated postmortem or in vivo through serial colonoscopies. Sepsis-surviving mice (SSM) presented with a lower colonic DNA damage, polyp incidence, reduced tumor load, and milder colitis than their sham-operated counterparts. Ablating Treg led to restoration of the ability to develop colitis and tumor polyps in the SSM, in a similar fashion to that in the sham-operated mice. On the other hand, the growth of subcutaneously inoculated MC38luc colorectal cancer cells or previously established chemical CAC tumors was increased in SSM. CONCLUSION: Our results provide evidence that postsepsis disorder has a dual effect in cancer development, inhibiting inflammation-induced early carcinogenesis in a Treg-dependent manner, while increasing the growth of previously established tumors.


Assuntos
Colite/complicações , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Inflamação/complicações , Sepse/complicações , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/imunologia , Animais , Colite/imunologia , Colite/patologia , Neoplasias do Colo/etiologia , Citocinas/metabolismo , Feminino , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Sepse/imunologia , Sepse/patologia , Transdução de Sinais
5.
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
6.
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
7.
J Am Coll Nutr ; 38(2): 162-170, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30211662

RESUMO

OBJECTIVE: Colon cancer occupies the third place in incidence worldwide; eating habits, in particular, consumption of hypercaloric diets, are relevant in its etiopathogenesis. On the other hand, foods can also modulate carcinogenesis: for example, proteins, which when hydrolyzed release peptides with biological activities, and legumes, especially, chickpea, represent a good source of hydrolysates. The objective of this work was to verify the inhibitory effect of chickpea hydrolyzed protein on azoxymethane (AOM)-induced carcinogenesis in mice fed a hypercaloric diet. METHODS: We hydrolyzed chickpea protein by pepsin, pancreatin, and a combined pepsin-pancreatin system, to test its anticarcinogenic and hypercaloric activity in mice that had consumed a hypercaloric diet or a normal diet but were injected with azoxymethane (AOM). RESULTS: A concentrate (70% proteins) was obtained from chickpea seeds (18.5% proteins), and extensive hydrolysates were obtained at 15 minutes, in all tested enzyme systems. The greatest activity was evidenced in the hydrolysates obtained with pepsin-pancreatin at 90 minutes. Animals that consumed the hypercaloric diet had a higher concentration of cholesterol and a higher atherogenic index, which were significantly reduced with the administration of chickpea protein hydrolysates with a dose-response effect (10, 20, or 30 mg/kg), whereas no effect was observed in animals that consumed the normal diet. In animals given AOM, aberrant crypts were observed, at a higher rate in animals that consumed the hypercaloric diet; with the consumption of hydrolysates by the animals that consumed either diet, the number of aberrant crypts was reduced with the 3 doses tested, and the effect was better in those animals fed the hypercaloric diet. The best effect in all tests was with 30 mg/kg body weight. CONCLUSION: The consumption of chickpea protein hydrolysates might confer a protective effect against colon carcinogenesis.


Assuntos
Carcinogênese/efeitos dos fármacos , Cicer/química , Substâncias Protetoras/farmacologia , Hidrolisados de Proteína/farmacologia , Sementes/química , Animais , Azoximetano , Carcinogênese/induzido quimicamente , Colo/efeitos dos fármacos , Neoplasias do Colo/etiologia , Dieta/efeitos adversos , Dieta/métodos , Modelos Animais de Doenças , Ingestão de Energia , Masculino , Camundongos
8.
Chemosphere ; 209: 623-631, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29957523

RESUMO

Environmental factors may increase colon cancer (CC) risk. It has been suggested that pesticides could play a significant role in the etiology of this malignancy. As agriculture is one of the mainstays of the Brazilian economy, this country has become the largest pesticides consumer worldwide. The CC burden is also increasing in Brazil. Herein, we examined data from the Brazilian Federal Government to determine whether CC mortality and pesticide consumption may be associated. Database of the Ministry of Health provided CC mortality data in Brazil, while pesticide usage was accessed at the website of Brazilian Institute of Environment and Renewable Natural Resources. The CC mortality in the Brazilian states was calculated as standard mortality rates (SMR). All Bayesian analysis was performed using a Markov chain Monte Carlo method in WinBUGS software. We observed that CC mortality has exhibited a steady increase for more than a decade, which correlated with the amount of sold pesticides in the country. Both observations are concentrated in the Southern and the Southeast regions of Brazil. Although ecological studies like ours have methodological limitations, the current dataset suggests the possibility that pesticide exposure may be a risk factor for CC. It warrants further investigation.


Assuntos
Neoplasias do Colo/etiologia , Praguicidas/efeitos adversos , Brasil , Neoplasias do Colo/patologia , Humanos , Fatores de Risco
9.
Food Chem Toxicol ; 112: 11-18, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29269057

RESUMO

The risk of developing colorectal cancer (CRC) could be associated with red and processed meat intake. Experimental data supports that hemin iron, found abundantly in red meat, promotes CRC in mice and rats, while indole-3 carbinol (I3C) and synbiotics (syn) exert anti-carcinogenic activities in most studies of colon carcinogenesis. This study aimed to investigate the modifying effects of I3C and syn (inulin + Bifidobacterium lactis), given separately or together, on dimethylhidrazine (DMH)-induced colon carcinogenesis in hemin-fed rats. All animals were given four subcutaneous DMH injections and then, two weeks after carcinogen exposure, they began a basal diet containing hemin, hemin + I3C, hemin + syn, or hemin + I3C + syn for 23 weeks. The combination of I3C + syn significantly increased fecal water genotoxicity, tumor volume and invasiveness when compared to the hemin-fed control group. The groups fed I3C or syn alone had a significant reduction in the number of preneoplastic aberrant crypt foci (ACF) lesions compared to the hemin-fed group. Dietary I3C also reduced fecal water genotoxicity. Gene expression analysis of colorectal tumors demonstrated that the combination of dietary I3C + syn increased transcript levels for Raf1 and decreased tumor progression and invasiveness related to the genes Cdh1 and Appl1. This analysis also revealed that the Tnf and Cdh1 genes were significantly up- and down-regulated, respectively, in tumors of rats that received I3C, in comparison with the hemin-fed group. These findings reveal that the joint administration of I3C and syn enhanced the development of colon tumors induced by DMH in hemin-fed rats, while they potentially reduced ACF development when given alone.


Assuntos
Anticarcinógenos/administração & dosagem , Cocarcinogênese , Neoplasias do Colo/etiologia , Hemina/efeitos adversos , Indóis/administração & dosagem , Carne Vermelha/efeitos adversos , Simbióticos/administração & dosagem , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Células CACO-2 , Caderinas/genética , Carcinógenos/toxicidade , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Ensaio Cometa , Dimetilidrazinas/toxicidade , Progressão da Doença , Perfilação da Expressão Gênica , Hemina/administração & dosagem , Humanos , Peroxidação de Lipídeos , Masculino , Invasividade Neoplásica/genética , Proteínas do Tecido Nervoso/genética , Proteínas Proto-Oncogênicas c-raf/genética , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética
10.
Clin Transl Oncol ; 20(3): 302-312, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28808878

RESUMO

OBJECTIVE: Chronic intestinal inflammation is a risk factor for colorectal cancer (CRC) initiation and development. Diets that are rich in Western style fats have been shown to promote CRC. This study was conducted to investigate the role of intestinal microbiome in American ginseng-mediated CRC chemoprevention in a mouse model. The population and diversity of enteric microbiome were evaluated after the ginseng treatment. METHODS: Using an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced gut inflammation and tumorigenesis mouse model, the effects of oral American ginseng on high fat diet-associated enteric pathology were determined. After establishment of a 16S rRNA illumina library from fecal samples, MiSeq sequencing was carried out to reveal the microbial population. The alpha and beta diversities of microbiome were analyzed. RESULTS: American ginseng significantly attenuated AOM/DSS-induced colon inflammation and tumorigenesis by reducing the colitis score and colon tumor multiplicity. The MiSeq results showed that the majority of sequences fell into three phyla: Firmicutes, Bacteroidetes and Verrucomicrobia. Further, two significant abundance shifts at the family level, Bacteroidaceae and Porphyromonadaceae, were identified to support ginseng's anti-colitis and anti-tumor effects. In addition, alpha and beta diversity data demonstrated that ginseng led to a profound recovery from the AOM/DSS-induced dysbiosis in the microbial community. CONCLUSION: Our results suggest that the CRC chemopreventive effects of American ginseng are mediated through enteric microbiome population-shift recovery and dysbiosis restoration. Ginseng's regulation of the microbiome balance contributes to the maintenance of enteric homeostasis.


Assuntos
Carcinogênese/efeitos dos fármacos , Neoplasias do Colo/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Panax , Extratos Vegetais/farmacologia , Animais , Azoximetano/toxicidade , Carcinogênese/induzido quimicamente , Carcinogênese/patologia , Colite/etiologia , Colite/microbiologia , Colite/patologia , Neoplasias do Colo/etiologia , Neoplasias do Colo/microbiologia , Sulfato de Dextrana/toxicidade , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Raízes de Plantas
11.
Crit Rev Oncol Hematol ; 116: 125-133, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28693794

RESUMO

Adipose tissue synthesizes many proteins and hormones collectively called adipokines, which are linked to a number of diseases, including cancer. Low levels of adiponectin are reported to be a risk factor for obesity-related cancers including colorectal and prostate cancers. Accordingly, obesity/lifestyle-related diseases, including certain cancers, may be treated by developing drugs that act specifically on adiponectin levels in circulation. Adiponectin may also serve as a clinical biomarker in obesity-related diseases. Adiponectin-based therapies are known to inhibit cancer advancement and thus may provide a therapeutic approach to delay cancer progression. Better understanding of the function of adiponectin is of great significance in the fight against cancer. This timely review is concentrated on the role of adiponectin and the impact of obesity on the development of cancers, especially colorectal and prostate cancers.


Assuntos
Adiponectina/metabolismo , Neoplasias do Colo/etiologia , Obesidade/complicações , Neoplasias da Próstata/etiologia , Animais , Neoplasias do Colo/metabolismo , Humanos , Masculino , Obesidade/metabolismo , Neoplasias da Próstata/metabolismo , Fatores de Risco
12.
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
13.
Probiotics Antimicrob Proteins ; 9(2): 163-171, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28316010

RESUMO

The administration of probiotics is a promising approach to reduce the prevalence of colon cancer, a multifactorial disease, with hereditary factors, as well as environmental lifestyle-related risk factors. Biogenic polyamines, putrescine, spermidine, and spermine are small cationic molecules with great roles in cell proliferation and differentiation as well as regulation of gene expression. Ornithine decarboxylase is the first rate-limiting enzyme for polyamine synthesis, and upregulation of ornithine decarboxylase activity and polyamine metabolism has been associated with abnormal cell proliferation. This paper is focused on studying the protective role of Lactobacillus casei ATCC 393 in a chemically induced mouse model of colon carcinogenesis, directing our attention on aberrant crypt foci as preneoplastic markers, and on polyamine metabolism as a possible key player in carcinogenesis. BALB/c mice were administered 1,2-dimethylhydrazine dihydrochloride (DMH) to induce colon cancer (20 mg/kg body weight, subcutaneous, twice a week for 24 weeks). L. casei ATCC 393 was given orally (106 CFU, twice a week), 2 weeks before DMH administration. Hematoxylin and eosin staining, high-performance liquid chromatography, and Western blotting were used to evaluate aberrant crypt foci, urinary polyamines, and ornithine decarboxylase expression in the colon. The experimental data showed that the preventive administration of L. casei ATCC 393 may delay the onset of cancer as it significantly reduced the number of DMH-induced aberrant crypt foci, the levels of putrescine, and the expression of ornithine decarboxylase. Hence, this probiotic strain has a prospective role in protection against colon carcinogenesis, and its antimutagenic activity may be associated with the maintenance of polyamine metabolism.


Assuntos
Neoplasias do Colo/prevenção & controle , Dimetilidrazinas/toxicidade , Lacticaseibacillus casei/fisiologia , Probióticos/administração & dosagem , Animais , Carcinogênese , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/microbiologia , Neoplasias do Colo/etiologia , Neoplasias do Colo/metabolismo , Feminino , Humanos , Lacticaseibacillus casei/genética , Camundongos , Poliaminas/metabolismo
14.
Toxicol Lett ; 265: 106-116, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27908614

RESUMO

Colon cancer is one of the most common malignancies and its etiology closely tied to dietary habits. Recent epidemiological data shows that colon cancer incidence is shifting to a much younger population. In this regard, some dietary components from a regular human meal might have various DNA-damaging compounds. Given that not every person endure cancer, the colonic malignancy develops throughout decades, and persistent DNA damage promotes cancer when induced at the proper intensity, a critical discussion of possible novel mechanisms by which carcinogens promote these tumors is urgently needed. Robust genomic sequencing analyses showed that low and late cell cycle expressed genes are prone to undergo mutation. Moreover, detection and repair mechanisms have a particular threshold to be activated throughout the G2/M phase, and reactivation of these devices during the M phase promotes genomic instability. Conditions of combined exposure to non-genotoxic concentrations of various carcinogens seem to act effectively through these weaknesses in genomic repair mechanisms. Therefore, we suggest that the natural tolerance of body defence mechanisms eventually become overwhelmed by the chronic exposure to different combinations and intensities of dietary mutagens leading to the high incidence of colon cancer in modern society.


Assuntos
Neoplasias do Colo/etiologia , Dano ao DNA , Reparo do DNA , Dieta Ocidental/efeitos adversos , Poluentes Ambientais/toxicidade , Instabilidade Genômica , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Instabilidade Genômica/efeitos dos fármacos , Humanos
16.
PLoS Negl Trop Dis ; 9(4): e0003744, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25884710

RESUMO

BACKGROUND: Trypanosomiasis induces a remarkable myenteric neuronal degeneration leading to megacolon. Very little is known about the risk for colon cancer in chagasic megacolon patients. To clarify whether chagasic megacolon impacts on colon carcinogenesis, we investigated the risk for colon cancer in Trypanosoma cruzi (T. cruzi) infected patients and rats. METHODS: Colon samples from T. cruzi-infected and uninfected patients and rats were histopathologically investigated with colon cancer biomarkers. An experimental model for chemical myenteric denervation was also performed to verify the myenteric neuronal effects on colon carcinogenesis. All experiments complied the guidelines and approval of ethical institutional review boards. RESULTS: No colon tumors were found in chagasic megacolon samples. A significant myenteric neuronal denervation was observed. Epithelial cell proliferation and hyperplasia were found increased in chagasic megacolon. Analyzing the argyrophilic nucleolar organiser regions within the cryptal bottom revealed reduced risk for colon cancer in Chagas' megacolon patients. T. cruzi-infected rats showed a significant myenteric neuronal denervation and decreased numbers of colon preneoplastic lesions. In chemical myenteric denervated rats preneoplastic lesions were reduced from the 2nd wk onward, which ensued having the colon myenteric denervation significantly induced. CONCLUSION/SIGNIFICANCE: Our data suggest that the trypanosomiasis-related myenteric neuronal degeneration protects the colon tissue from carcinogenic events. Current findings highlight potential mechanisms in tropical diseases and cancer research.


Assuntos
Doença de Chagas/complicações , Neoplasias do Colo/etiologia , Megacolo/complicações , Megacolo/etiologia , Plexo Mientérico/citologia , Neurônios/patologia , Trypanosoma cruzi , Animais , Biomarcadores Tumorais , Doença de Chagas/patologia , Células Epiteliais/patologia , Humanos , Masculino , Plexo Mientérico/parasitologia , Neurônios/parasitologia , Ratos , Medição de Risco/métodos
17.
Acta Gastroenterol Latinoam ; 45(3): 198-202, 2015 09.
Artigo em Espanhol | MEDLINE | ID: mdl-28590602

RESUMO

INTRODUCTION: XSome authors have assessed the link between obesity and colon adenoma risk. Moreover, it has been reported that obesity could increase the risk of proximal adenoma development. Accordingly, obese patients may have a distinctive pattern of adenoma recurrence. AIM: To determine whether metachronous adenoma features differ between obese and non-obese subjects submitted to colonoscopy surveillance. MATERIALS AND METHODS: We prospectively evaluated all patients over 18 years old that underwent surveillance colonoscopy at our institution between June 2013 and June 2014. Date of prior colonoscopy was registered. A body mass index ≥ 30 was used to define obesity. Analysis looking for variables significantly associated with metachronous adenoma was performed. Metachronous adenoma rate was compared between obese and non-obese subjects, as well as size, location, morphological and histopathological characteristics. RESULTS: Overall, 825 subjects were enrolled. Median time of surveillance colonoscopy was 38.9 months. Obesity was statistically more frequent in those subjects with metachronous adenomas (40% vs 25.71%, p < 0.001). On multivariate analysis, obesity [OR 1.7 (1.01-2.9)] and age [OR 1.02 (1-1.05)] were independently associated with metachronous adenoma presence. Obesity was also significantly associated with a higher risk of right colon adenomas [OR 2.4 (1.76-3.26)] and advanced adenoma [OR 1.99 (1.29-3.06)]. The risk is significantly higher in men and in those with a family history of colorectal cancer/adenoma. CONCLUSION: Obesity was associated with a higher risk of metachronous adenomas on surveillance colonoscopy. A higher risk of right-sided lesions and advanced adenomas was also found in this population.


Assuntos
Adenoma/etiologia , Neoplasias do Colo/etiologia , Obesidade/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Colonoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Fatores de Risco
18.
Cell Mol Life Sci ; 71(17): 3191-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24848584

RESUMO

Several different cell types constitute the intestinal wall and interact in different manners to maintain tissue homeostasis. Elegant reports have explored these physiological cellular interactions revealing that glial cells and neurons not only modulate peristalsis and mechanical stimulus in the intestines but also control epithelial proliferation and sub-epithelial angiogenesis. Although colon carcinoma arises from epithelial cells, different sub-epithelial cell phenotypes are known to support the manifestation and development of tumors from their early steps on. Therefore, new perspectives in cancer research have been proposed, in which neurons and glial cells not only lead to higher cancer cell proliferation at the tumor invasion front but also further enhance angiogenesis and neurogenesis in tumors. Transformation of physiological neural activity into a pro-cancer event is thus discussed for colon carcinogenesis herein.


Assuntos
Adenocarcinoma/patologia , Transformação Celular Neoplásica/patologia , Neoplasias do Colo/patologia , Células Endoteliais/fisiologia , Células Epiteliais/fisiologia , Neuroglia/fisiologia , Neurônios/fisiologia , Adenocarcinoma/etiologia , Adenoma/etiologia , Adenoma/patologia , Animais , Comunicação Celular , Transformação Celular Neoplásica/genética , Neoplasias do Colo/etiologia , Progressão da Doença , Sistema Nervoso Entérico/patologia , Retroalimentação Fisiológica , Humanos , Inflamação , Mucosa Intestinal/patologia , Intestinos/irrigação sanguínea , Camundongos , Camundongos Transgênicos , Mutação , Invasividade Neoplásica , Células-Tronco Neoplásicas/fisiologia , Neovascularização Patológica/fisiopatologia , Serotonina/fisiologia , Microambiente Tumoral
19.
Rev Gastroenterol Peru ; 33(2): 147-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23838942

RESUMO

Colorectal cancer (CRC) is the third most common cancer in the world. Fortunately, it is also proven to be one of the most preventable cancers, in large part due to the utilization of CRC screening. Historically, it was believed that the adenomatous polyp was the only precursor to carcinoma of the colorectum. Within the last decade, it has been shown that approximately 20-30% of sporadic colon cancers arise through a distinct molecular pathway called CpG Island Methylation (CIMP) which is due to widespread DNA methylation. There is strong evidence that serrated polyps are the precursor lesions for colon cancers arising through the CIMP pathway.


Assuntos
Neoplasias do Colo/etiologia , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Pólipos do Colo/etiologia , Ilhas de CpG/genética , Metilação de DNA , Humanos
20.
Rev. gastroenterol. Perú ; 33(2): 147-151, abr.-jun. 2013. ilus, tab
Artigo em Inglês | LILACS, LIPECS | ID: lil-692432

RESUMO

Colorectal cancer (CRC) is the third most common cancer in the world. Fortunately, it is also proven to be one of the most preventable cancers, in large part due to the utilization of CRC screening. Historically, it was believed that the adenomatous polyp was the only precursor to carcinoma of the colorectum. Within the last decade, it has been shown that approximately 20-30% of sporadic colon cancers arise through a distinct molecular pathway called CpG Island Methylation (CIMP) which is due to widespread DNA methylation. There is strong evidence that serrated polyps are the precursor lesions for colon cancers arising through the CIMP pathway.


Cáncer Colorectal (CRC) es el tercer cáncer más común en el mundo (1). Afortunadamente también se ha probado que es el cáncer que más se puede prevenir, en gran parte debido al "screening" del CRC. Históricamente, se creía que el pólipo adenomatoso era el único precursor del carcinoma de colon y recto. En la última década se ha demostrado que aproximadamente el 20 al 30% de los cánceres colónicos esporádicos se derivan de una vía molecular diferente llamada Metilación de las Islas CpG (CIMP) que es debida a una extensión de la metilación del DNA.Actualmente hay una fuerte evidencia que los pólipos serrados son las lesiones precursoras de cáncer de colon surgiendo desde la vía CIMP.


Assuntos
Humanos , Neoplasias do Colo/etiologia , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Pólipos do Colo/etiologia , Ilhas de CpG/genética , Metilação de DNA
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