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1.
Cell ; 173(2): 338-354.e15, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29625051

RESUMO

Cancer progression involves the gradual loss of a differentiated phenotype and acquisition of progenitor and stem-cell-like features. Here, we provide novel stemness indices for assessing the degree of oncogenic dedifferentiation. We used an innovative one-class logistic regression (OCLR) machine-learning algorithm to extract transcriptomic and epigenetic feature sets derived from non-transformed pluripotent stem cells and their differentiated progeny. Using OCLR, we were able to identify previously undiscovered biological mechanisms associated with the dedifferentiated oncogenic state. Analyses of the tumor microenvironment revealed unanticipated correlation of cancer stemness with immune checkpoint expression and infiltrating immune cells. We found that the dedifferentiated oncogenic phenotype was generally most prominent in metastatic tumors. Application of our stemness indices to single-cell data revealed patterns of intra-tumor molecular heterogeneity. Finally, the indices allowed for the identification of novel targets and possible targeted therapies aimed at tumor differentiation.


Assuntos
Desdiferenciação Celular/genética , Aprendizado de Máquina , Neoplasias/patologia , Carcinogênese , Metilação de DNA , Bases de Dados Genéticas , Epigênese Genética , Humanos , MicroRNAs/metabolismo , Metástase Neoplásica , Neoplasias/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Transcriptoma , Microambiente Tumoral
2.
Mol Med ; 30(1): 43, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539088

RESUMO

BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that has been implicated in multiple inflammatory and non-inflammatory diseases, including liver injury induced by acetaminophen (APAP) overdose. Multiple small molecule inhibitors of MIF have been described, including the clinically available anti-rheumatic drug T-614 (iguratimod); however, this drug's mode of inhibition has not been fully investigated. METHODS: We conducted in vitro testing including kinetic analysis and protein crystallography to elucidate the interactions between MIF and T-614. We also performed in vivo experiments testing the efficacy of T-614 in a murine model of acetaminophen toxicity. We analyzed survival in lethal APAP overdose with and without T-614 and using two different dosing schedules of T-614. We also examined MIF and MIF inhibition effects on hepatic hydrogen peroxide (H2O2) as a surrogate of oxidative stress in non-lethal APAP overdose. RESULTS: Kinetic analysis was consistent with a non-competitive type of inhibition and an inhibition constant (Ki) value of 16 µM. Crystallographic analysis revealed that T-614 binds outside of the tautomerase active site of the MIF trimer, with only the mesyl group of the molecule entering the active site pocket. T-614 improved survival in lethal APAP overdose when given prophylactically, but this protection was not observed when the drug was administered late (6 h after APAP). T-614 also decreased hepatic hydrogen peroxide concentrations during non-lethal APAP overdose in a MIF-dependent fashion. CONCLUSIONS: T-614 is an allosteric inhibitor of MIF that prevented death and decreased hepatic hydrogen peroxide concentrations when given prophylactically in a murine model of acetaminophen overdose. Further studies are needed to elucidate the mechanistic role of MIF in APAP toxicity.


Assuntos
Benzopiranos , Doença Hepática Induzida por Substâncias e Drogas , Cromonas , Fatores Inibidores da Migração de Macrófagos , Sulfonamidas , Camundongos , Animais , Acetaminofen/efeitos adversos , Peróxido de Hidrogênio/metabolismo , Modelos Animais de Doenças , Cinética , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Estresse Oxidativo , Fígado/metabolismo
3.
FASEB J ; 36(6): e22335, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35506565

RESUMO

Dysregulated transforming growth factor-beta (TGF-ß) signaling contributes to fibrotic liver disease and hepatocellular cancer (HCC), both of which are associated with fatty liver disease. SIRT6 limits fibrosis by inhibiting TGF-ß signaling through deacetylating SMAD2 and SMAD3 and limits lipogenesis by inhibiting SREBP1 and SREBP2 activity. Here, we showed that, compared to wild-type mice, high-fat diet-induced fatty liver is worse in TGF-ß signaling-deficient mice (SPTBN1+/- ) and the mutant mice had reduced SIRT6 abundance in the liver. Therefore, we hypothesized that altered reciprocal regulation between TGF-ß signaling and SIRT6 contributes to these liver pathologies. We found that deficiency in SMAD3 or SPTBN1 reduced SIRT6 mRNA and protein abundance and impaired TGF-ß induction of SIRT6 transcripts, and that SMAD3 bound to the SIRT6 promoter, suggesting that an SMAD3-SPTBN1 pathway mediated the induction of SIRT6 in response to TGF-ß. Overexpression of SIRT6 in HCC cells reduced the expression of TGF-ß-induced genes, consistent with the suppressive role of SIRT6 on TGF-ß signaling. Manipulation of SIRT6 abundance in HCC cells altered sterol regulatory element-binding protein (SREBP) activity and overexpression of SIRT6 reduced the amount of acetylated SPTBN1 and the abundance of both SMAD3 and SPTBN1. Furthermore, induction of SREBP target genes in response to SIRT6 overexpression was impaired in SPTBN1 heterozygous cells. Thus, we identified a regulatory loop between SIRT6 and SPTBN1 that represents a potential mechanism for susceptibility to fatty liver in the presence of dysfunctional TGF-ß signaling.


Assuntos
Carcinoma Hepatocelular , Fígado Gorduroso , Sirtuínas , Fator de Crescimento Transformador beta , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fibrose , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Sirtuínas/genética , Proteína de Ligação a Elemento Regulador de Esterol 1 , Fator de Crescimento Transformador beta/metabolismo
4.
Int J Mol Sci ; 24(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36768686

RESUMO

The emerging field of immuno-oncology has brought exciting developments in the treatment of hepatocellular carcinoma (HCC). It has also raised urgent questions about the role of immunotherapy in the setting of liver transplantation, both before and after transplant. A growing body of evidence points to the safety and efficacy of immunotherapeutic agents as potential adjuncts for successful down-staging of advanced HCCs to allow successful transplant in carefully selected patients. For patients with recurrent HCC post-transplant, immunotherapy has a limited, yet growing role. In this review, we describe optimal regimens in the setting of liver transplantation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Imunoterapia
5.
Gastroenterology ; 161(2): 434-452.e15, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33940008

RESUMO

Genetic alterations affecting transforming growth factor-ß (TGF-ß) signaling are exceptionally common in diseases and cancers of the gastrointestinal system. As a regulator of tissue renewal, TGF-ß signaling and the downstream SMAD-dependent transcriptional events play complex roles in the transition from a noncancerous disease state to cancer in the gastrointestinal tract, liver, and pancreas. Furthermore, this pathway also regulates the stromal cells and the immune system, which may contribute to evasion of the tumors from immune-mediated elimination. Here, we review the involvement of the TGF-ß pathway mediated by the transcriptional regulators SMADs in disease progression to cancer in the digestive system. The review integrates human genomic studies with animal models that provide clues toward understanding and managing the complexity of the pathway in disease and cancer.


Assuntos
Neoplasias do Sistema Digestório/metabolismo , Gastroenteropatias/metabolismo , Hepatopatias/metabolismo , Pancreatopatias/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Neoplasias do Sistema Digestório/genética , Neoplasias do Sistema Digestório/patologia , Progressão da Doença , Gastroenteropatias/genética , Gastroenteropatias/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Hepatopatias/genética , Hepatopatias/patologia , Pancreatopatias/genética , Pancreatopatias/patologia , Receptores de Fatores de Crescimento Transformadores beta/genética , Transdução de Sinais , Proteínas Smad/genética , Fator de Crescimento Transformador beta/genética , Microambiente Tumoral
6.
Gastroenterology ; 158(1): 238-252, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585122

RESUMO

BACKGROUND & AIMS: We studied interactions among proteins of the carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family, which interact with microbes, and transforming growth factor beta (TGFB) signaling pathway, which is often altered in colorectal cancer cells. We investigated mechanisms by which CEACAM proteins inhibit TGFB signaling and alter the intestinal microbiome to promote colorectal carcinogenesis. METHODS: We collected data on DNA sequences, messenger RNA expression levels, and patient survival times from 456 colorectal adenocarcinoma cases, and a separate set of 594 samples of colorectal adenocarcinomas, in The Cancer Genome Atlas. We performed shotgun metagenomic sequencing analyses of feces from wild-type mice and mice with defects in TGFB signaling (Sptbn1+/- and Smad4+/-/Sptbn1+/-) to identify changes in microbiota composition before development of colon tumors. CEACAM protein and its mutants were overexpressed in SW480 and HCT116 colorectal cancer cell lines, which were analyzed by immunoblotting and proliferation and colony formation assays. RESULTS: In colorectal adenocarcinomas, high expression levels of genes encoding CEACAM proteins, especially CEACAM5, were associated with reduced survival times of patients. There was an inverse correlation between expression of CEACAM genes and expression of TGFB pathway genes (TGFBR1, TGFBR2, and SMAD3). In colorectal adenocarcinomas, we also found an inverse correlation between expression of genes in the TGFB signaling pathway and genes that regulate stem cell features of cells. We found mutations encoding L640I and A643T in the B3 domain of human CEACAM5 in colorectal adenocarcinomas; structural studies indicated that these mutations would alter the interaction between CEACAM5 and TGFBR1. Overexpression of these mutants in SW480 and HCT116 colorectal cancer cell lines increased their anchorage-independent growth and inhibited TGFB signaling to a greater extent than overexpression of wild-type CEACAM5, indicating that they are gain-of-function mutations. Compared with feces from wild-type mice, feces from mice with defects in TGFB signaling had increased abundance of bacterial species that have been associated with the development of colon tumors, including Clostridium septicum, and decreased amounts of beneficial bacteria, such as Bacteroides vulgatus and Parabacteroides distasonis. CONCLUSION: We found expression of CEACAMs and genes that regulate stem cell features of cells to be increased in colorectal adenocarcinomas and inversely correlated with expression of TGFB pathway genes. We found colorectal adenocarcinomas to express mutant forms of CEACAM5 that inhibit TGFB signaling and increase proliferation and colony formation. We propose that CEACAM proteins disrupt TGFB signaling, which alters the composition of the intestinal microbiome to promote colorectal carcinogenesis.


Assuntos
Antígeno Carcinoembrionário/genética , Carcinogênese/genética , Neoplasias Colorretais/genética , Microbioma Gastrointestinal/fisiologia , Transdução de Sinais/genética , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Antígeno Carcinoembrionário/metabolismo , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/mortalidade , Modelos Animais de Doenças , Fezes/microbiologia , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Mutação com Ganho de Função , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Metagenômica , Camundongos , Camundongos Transgênicos , Domínios Proteicos/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Esferoides Celulares , Análise de Sobrevida , Fator de Crescimento Transformador beta/metabolismo
7.
Gastroenterology ; 154(1): 195-210, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28918914

RESUMO

BACKGROUND & AIMS: Development of hepatocellular carcinoma (HCC) is associated with alterations in the transforming growth factor-beta (TGF-ß) signaling pathway, which regulates liver inflammation and can have tumor suppressor or promoter activities. Little is known about the roles of specific members of this pathway at specific of HCC development. We took an integrated approach to identify and validate the effects of changes in this pathway in HCC and identify therapeutic targets. METHODS: We performed transcriptome analyses for a total of 488 HCCs that include data from The Cancer Genome Atlas. We also screened 301 HCCs reported in the Catalogue of Somatic Mutations in Cancer and 202 from Cancer Genome Atlas for mutations in genome sequences. We expressed mutant forms of spectrin beta, non-erythrocytic 1 (SPTBN1) in HepG2, SNU398, and SNU475 cells and measured phosphorylation, nuclear translocation, and transcriptional activity of SMAD family member 3 (SMAD3). RESULTS: We found somatic mutations in at least 1 gene whose product is a member of TGF-ß signaling pathway in 38% of HCC samples. SPTBN1 was mutated in the largest proportion of samples (12 of 202, 6%). Unsupervised clustering of transcriptome data identified a group of HCCs with activation of the TGF-ß signaling pathway (increased transcription of genes in the pathway) and a group of HCCs with inactivation of TGF-ß signaling (reduced expression of genes in this pathway). Patients with tumors with inactivation of TGF-ß signaling had shorter survival times than patients with tumors with activation of TGF-ß signaling (P = .0129). Patterns of TGF-ß signaling correlated with activation of the DNA damage response and sirtuin signaling pathways. HepG2, SNU398, and SNU475 cells that expressed the D1089Y mutant or with knockdown of SPTBN1 had increased sensitivity to DNA crosslinking agents and reduced survival compared with cells that expressed normal SPTBN1 (controls). CONCLUSIONS: In genome and transcriptome analyses of HCC samples, we found mutations in genes in the TGF-ß signaling pathway in almost 40% of samples. These correlated with changes in expression of genes in the pathways; up-regulation of genes in this pathway would contribute to inflammation and fibrosis, whereas down-regulation would indicate loss of TGF-ß tumor suppressor activity. Our findings indicate that therapeutic agents for HCCs can be effective, based on genetic features of the TGF-ß pathway; agents that block TGF-ß should be used only in patients with specific types of HCCs.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Mutação/genética , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Idoso , Carcinoma Hepatocelular/mortalidade , Estudos de Casos e Controles , Análise por Conglomerados , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade
8.
Gut ; 67(7): 1299-1305, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28607096

RESUMO

OBJECTIVE: There are few studies which characterised the molecular alterations in premalignant colorectal adenomas. Our major goal was to establish colorectal adenoma genome atlas and identify molecular markers of progression from colorectal adenoma to adenocarcinoma. DESIGN: Whole-exome sequencing and targeted sequencing were carried out in 149 adenoma samples and paired blood from patients with conventional adenoma or sessile serrated adenoma to characterise the somatic mutation landscape for premalignant colorectal lesions. The identified somatic mutations were compared with those in colorectal cancer (CRC) samples from The Cancer Genome Atlas. A supervised random forest model was employed to identify gene panels differentiating adenoma from CRC. RESULTS: Similar somatic mutation frequencies, but distinctive driver mutations, were observed in sessile serrated adenomas and conventional adenomas. The final model included 20 genes and was able to separate the somatic mutation profile of colorectal adenoma and adenocarcinoma with an area under the curve of 0.941. CONCLUSION: The findings of this project hold potential to better identify patients with adenoma who may be candidates for targeted surveillance programmes and preventive interventions to reduce the incidence of CRC.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Mutação/genética , Lesões Pré-Cancerosas/genética , Adenocarcinoma/patologia , Adenoma/patologia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Sequenciamento do Exoma
10.
Gastroenterology ; 152(6): 1477-1491, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28143772

RESUMO

BACKGROUND & AIMS: Stearoyl-CoA desaturase (SCD) synthesizes monounsaturated fatty acids (MUFAs) and has been associated with the development of metabolic syndrome, tumorigenesis, and stem cell characteristics. We investigated whether and how SCD promotes liver fibrosis and tumor development in mice. METHODS: Rodent primary hepatic stellate cells (HSCs), mouse liver tumor-initiating stem cell-like cells (TICs), and human hepatocellular carcinoma (HCC) cell lines were exposed to Wnt signaling inhibitors and changes in gene expression patterns were analyzed. We assessed the functions of SCD by pharmacologic and conditional genetic manipulation in mice with hepatotoxic or cholestatic induction of liver fibrosis, orthotopic transplants of TICs, or liver tumors induced by administration of diethyl nitrosamine. We performed bioinformatic analyses of SCD expression in HCC vs nontumor liver samples collected from patients, and correlated levels with HCC stage and patient mortality. We performed nano-bead pull-down assays, liquid chromatography-mass spectrometry, computational modeling, and ribonucleoprotein immunoprecipitation analyses to identify MUFA-interacting proteins. We examined the effects of SCD inhibition on Wnt signaling, including the expression and stability of low-density lipoprotein-receptor-related proteins 5 and 6 (LRP5 and LRP6), by immunoblot and quantitative polymerase chain reaction analyses. RESULTS: SCD was overexpressed in activated HSC and HCC cells from patients; levels of SCD messenger RNA (mRNA) correlated with HCC stage and patient survival time. In rodent HSCs and TICs, the Wnt effector ß-catenin increased sterol regulatory element binding protein 1-dependent transcription of Scd, and ß-catenin in return was stabilized by MUFAs generated by SCD. This loop required MUFA inhibition of binding of Ras-related nuclear protein 1 (Ran1) to transportin 1 and reduced nuclear import of elav-like protein 1 (HuR), increasing cytosolic levels of HuR and HuR-mediated stabilization of mRNAs encoding LRP5 and LRP6. Genetic disruption of Scd and pharmacologic inhibitors of SCD reduced HSC activation and TIC self-renewal and attenuated liver fibrosis and tumorigenesis in mice. Conditional disruption of Scd2 in activated HSCs prevented growth of tumors from TICs and reduced the formation of diethyl nitrosamine-induced liver tumors in mice. CONCLUSIONS: In rodent HSCs and TICs, we found SCD expression to be regulated by Wnt-ß-catenin signaling, and MUFAs produced by SCD provided a forward loop to amplify Wnt signaling via stabilization of Lrp5 and Lrp6 mRNAs, contributing to liver fibrosis and tumor growth. SCD expressed by HSCs promoted liver tumor development in mice. Components of the identified loop linking HSCs and TICs might be therapeutic targets for liver fibrosis and tumors.


Assuntos
Carcinoma Hepatocelular/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Via de Sinalização Wnt/genética , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Colestase/complicações , Dietilnitrosamina , Proteína Semelhante a ELAV 1/metabolismo , Células Estreladas do Fígado , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Camundongos , Estadiamento de Neoplasias , Transplante de Neoplasias , Células-Tronco Neoplásicas , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Taxa de Sobrevida , Transcrição Gênica , beta Catenina/metabolismo , beta Carioferinas/metabolismo , Proteína ran de Ligação ao GTP/metabolismo
11.
Hepatology ; 65(4): 1222-1236, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27863449

RESUMO

Hepatocellular carcinoma (HCC) is the second-leading cause of cancer-related deaths worldwide with a poor survival rate. As many as 40% of HCCs are clonal, with alteration of key tumor-suppressor pathways in stem cells as the primary cause of HCC initiation. However, mechanisms that generate metastatic stem cells in preneoplastic liver tissue are not well understood. We hypothesized that chronic inflammation is a major driver of the transformation of genetically defective liver stem cells (LSCs) into highly metastatic liver cancer cells in premalignant liver tissue. We developed models of chronic inflammation in wild-type (WT) and ß2-spectrin (ß2SP)+/- (SPTBN1) mice. CD133+ LSCs derived from preneoplastic livers of ß2SP+/- mice treated with interleukin-6 (pIL6; IL6 ß2SP+/- LSCs) were highly tumorigenic and metastatic, whereas those derived from WT mice treated with pIL6 (IL6 WT LSCs) had significantly less proliferation and no tumorigenic properties. IL6 ß2SP+/- LSCs not only exhibited nuclear localization of Twist and Slug, markers of epithelial-mesenchymal transition (EMT), but also constitutive activation of nuclear factor kappa B (NFκB; RELA). Knockdown of NFκB decreased the EMT phenotypes and metastatic capacity of these cells. NFκB in IL6 ß2SP+/- LSCs was activated by transforming growth factor ß (TGFß)-activated kinase 1 (TAK1; MAP3K7), which is associated with poor survival in HCC and interleukin-6 (IL6) expression. The amount of constitutively activated NFκB increased dramatically from normal to cirrhotic to HCC tissues from human patients. CONCLUSION: IL6-mediated inflammation programs constitutive activation of the TAK1-NFκB signaling cascade in CD133+ LSCs, and this program interacts with deficient TGFß signaling, thereby accelerating the transformation of normal LSCs to metastatic cancer stem cells (mCSCs). Indeed, this study delineates the development of EMT-positive mCSCs in HCC-free liver tissue upon chronic inflammation. (Hepatology 2017;65:1222-1236).


Assuntos
Carcinoma Hepatocelular/patologia , Interleucina-6/farmacologia , Neoplasias Hepáticas/patologia , MAP Quinase Quinase Quinases/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Biópsia por Agulha , Western Blotting , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , MAP Quinase Quinase Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/metabolismo , Distribuição Aleatória , Estatísticas não Paramétricas , Fator de Crescimento Transformador beta1/efeitos dos fármacos
12.
Hepatology ; 65(2): 678-693, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28114741

RESUMO

Exposure to genotoxins such as ethanol-derived acetaldehyde leads to DNA damage and liver injury and promotes the development of cancer. We report here a major role for the transforming growth factor ß/mothers against decapentaplegic homolog 3 adaptor ß2-Spectrin (ß2SP, gene Sptbn1) in maintaining genomic stability following alcohol-induced DNA damage. ß2SP supports DNA repair through ß2SP-dependent activation of Fanconi anemia complementation group D2 (Fancd2), a core component of the Fanconi anemia complex. Loss of ß2SP leads to decreased Fancd2 levels and sensitizes ß2SP mutants to DNA damage by ethanol treatment, leading to phenotypes that closely resemble those observed in animals lacking both aldehyde dehydrogenase 2 and Fancd2 and resemble human fetal alcohol syndrome. Sptbn1-deficient cells are hypersensitive to DNA crosslinking agents and have defective DNA double-strand break repair that is rescued by ectopic Fancd2 expression. Moreover, Fancd2 transcription in response to DNA damage/transforming growth factor ß stimulation is regulated by the ß2SP/mothers against decapentaplegic homolog 3 complex. CONCLUSION: Dysfunctional transforming growth factor ß/ß2SP signaling impacts the processing of genotoxic metabolites by altering the Fanconi anemia DNA repair pathway. (Hepatology 2017;65:678-693).


Assuntos
Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Instabilidade Genômica/genética , Prenhez , Espectrina/genética , Fator de Crescimento Transformador beta2/genética , Análise de Variância , Animais , Animais Recém-Nascidos , Dano ao DNA/genética , Reparo do DNA/genética , Etanol/farmacologia , Feminino , Transtornos do Espectro Alcoólico Fetal/genética , Transtornos do Espectro Alcoólico Fetal/patologia , Humanos , Imuno-Histoquímica , Peroxidação de Lipídeos/genética , Camundongos , Camundongos Transgênicos , Gravidez , Reação em Cadeia da Polimerase em Tempo Real/métodos , Transdução de Sinais
13.
Dig Dis Sci ; 63(5): 1123-1138, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29572615

RESUMO

Colorectal cancer (CRC) accounts for ~9% of all cancers in the Veteran population, a fact which has focused a great deal of the attention of the VA's research and development efforts. A field-based meeting of CRC experts was convened to discuss both challenges and opportunities in precision medicine for CRC. This group, designated as the VA Colorectal Cancer Cell-genomics Consortium (VA4C), discussed advances in CRC biology, biomarkers, and imaging for early detection and prevention. There was also a discussion of precision treatment involving fluorescence-guided surgery, targeted chemotherapies and immunotherapies, and personalized cancer treatment approaches. The overarching goal was to identify modalities that might ultimately lead to personalized cancer diagnosis and treatment. This review summarizes the findings of this VA field-based meeting, in which much of the current knowledge on CRC prescreening and treatment was discussed. It was concluded that there is a need and an opportunity to identify new targets for both the prevention of CRC and the development of effective therapies for advanced disease. Also, developing methods integrating genomic testing with tumoroid-based clinical drug response might lead to more accurate diagnosis and prognostication and more effective personalized treatment of CRC.


Assuntos
Neoplasias Colorretais , Medicina de Precisão/métodos , Saúde dos Veteranos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/terapia , Terapia Combinada , Detecção Precoce de Câncer/métodos , Humanos , Prognóstico
14.
Adv Exp Med Biol ; 1032: 93-104, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30362093

RESUMO

Over 90% of hepatocellular carcinoma (HCC) occurs against a background of chronic liver disease or cirrhosis induced from viral hepatitis to alcohol injury. One third of patients with cirrhosis will develop HCC during their lifetime, with a 3-5% annual incidence. However, little is known about the key mechanisms by which toxins mediate DNA damage in the liver. Recent studies support a central role for TGF-ß signaling in conferring genomic stability yet the precise mechanism of action and the specific stages of tumor suppression remain unclear (Bornstein S, White R, Malkoski S, Oka M, Han G, Cleaver T, Reh D, Andersen P, Gross N, Olson S, Deng C, Lu SL, Wang XJ. J Clin Invest 119:3408-3419 (2009); Korc M. J Clin Invest 119:3208-3211 (2009); Glick A, Popescu N, Alexander V, Ueno H, Bottinger E, Yuspa SH. Proc Natl Acad Sci U S A 96:14949-14954 (1999)). Furthermore, it has recently been shown that ß2SP+/- and ß2SP+/-/Smad3+/- mice phenocopy a hereditary human cancer syndrome, the Beckwith-Wiedemann syndrome (BWS), which has an 800 fold risk of cancers including HCC, hepatoblastoma, and a range of liver disorders. Identifying key biological pathways and mechanisms for suppressing alcohol-induced stem cell injury and HCC will be critical for enhancing patient care and the employment of new therapeutic approaches.


Assuntos
Carcinoma Hepatocelular/etiologia , Cirrose Hepática/complicações , Hepatopatias Alcoólicas/complicações , Neoplasias Hepáticas/etiologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Síndrome de Beckwith-Wiedemann , Instabilidade Genômica , Humanos , Hepatopatias Alcoólicas/metabolismo , Camundongos
15.
Cancer ; 123(20): 4066-4074, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28640361

RESUMO

BACKGROUND: Patients with colorectal adenoma polyps (PLPs) are at higher risk for developing colorectal cancer (CRC). However, the development of improved and robust biomarkers to enable the screening, surveillance, and early detection of PLPs and CRC continues to be a challenge. The aim of this study was to identify biomarkers of progression to CRC through metabolomic profiling of human serum samples with a multistage approach. METHODS: Metabolomic profiling was conducted with the Metabolon platform for 30 CRC patients, 30 PLP patients, and 30 control subjects, and this was followed by the targeted validation of the top metabolites in an additional set of 50 CRC patients, 50 PLP patients, and 50 controls with liquid chromatography-tandem mass spectrometry. Unconditional multivariate logistic regression models, adjusted for covariates, were used to evaluate associations with PLP and CRC risk. RESULTS: For the discovery phase, 404 serum metabolites were detected, with 50 metabolites showing differential levels between CRC patients, PLP patients, and controls (P for trend < .05). After validation, the 3 top metabolites (xanthine, hypoxanthine, and d-mannose) were validated: lower levels of xanthine and hypoxanthine and higher levels of d-mannose were found in PLP and CRC cases versus controls. A further exploratory analysis of metabolic pathways revealed key roles for the urea cycle and caffeine metabolism associated with PLP and CRC risk. In addition, a joint effect of the top metabolites with smoking and a significant interaction with the body mass index were observed. An analysis of the ratio of hypoxanthine levels to xanthine levels indicated an association with CRC progression. CONCLUSIONS: These results suggest the potential utility of circulating metabolites as novel biomarkers for the early detection of CRC. Cancer 2017;123:4066-74. © 2017 American Cancer Society.


Assuntos
Adenoma/sangue , Pólipos do Colo/sangue , Neoplasias Colorretais/sangue , Adenoma/metabolismo , Adulto , Idoso , Cafeína/metabolismo , Estudos de Casos e Controles , Cromatografia Líquida , Pólipos do Colo/metabolismo , Neoplasias Colorretais/metabolismo , Progressão da Doença , Feminino , Humanos , Hipoxantina/sangue , Pólipos Intestinais/sangue , Pólipos Intestinais/metabolismo , Modelos Logísticos , Masculino , Manose/sangue , Metabolômica , Pessoa de Meia-Idade , Análise Multivariada , Espectrometria de Massas em Tandem , Ureia/metabolismo , Xantina/sangue
16.
J Vasc Surg ; 65(4): 1161-1169, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27288104

RESUMO

OBJECTIVE: Chronic nonhealing wounds are a major health problem for patients in the United States and worldwide. Diabetes and ischemia are two major risk factors behind impaired healing of chronic lower extremity wounds. Poly-ADP-ribose polymerase (PARP) is found to be overactivated with both ischemic and diabetic conditions. This study seeks a better understanding of the role of PARP in ischemic and diabetic wound healing, with a specific focus on angiogenesis and vasculogenesis. METHODS: Ischemic and diabetic wounds were created in FVB/NJ mice and an in vitro scratch wound model. PARP inhibitor PJ34 was delivered to the animals at 10 mg/kg/d through implanted osmotic pumps or added to the culture medium, respectively. Animal wound healing was assessed by daily digital photographs. Animal wound tissues, peripheral blood, and bone marrow cells were collected at different time points for further analysis with Western blot and flow cytometry. Scratch wound migration and invasion angiogenesis assays were performed using human umbilical vein endothelial cells (HUVECs). Measurements were reported as mean ± standard deviation. Continuous measurements were compared by t-test. P < .05 was considered statistically significant. RESULTS: A significant increase in PARP activity was observed under ischemic and diabetic conditions that correlated with delayed wound healing and slower HUVEC migration. The beneficial effect of PARP inhibition with PJ34 on ischemic and diabetic wound healing was observed in both animal and in vitro models. In the animal model, the percentage of wound healing was significantly enhanced from 43% ± 6% to 71% ± 9% (P < .05) by day 7 with the addition of PJ34. PARP inhibition promoted angiogenesis at the ischemic and diabetic wound beds as evidenced by significantly higher levels of endothelial cell markers (vascular endothelial growth factor receptor 2 [VEGFR2] and endothelial nitric oxide synthase) in mice treated with PJ34 compared with controls. Flow cytometry analysis of peripheral blood mononuclear cells showed that PARP inhibition increased mobilization of endothelial progenitor cells (VEGFR2+/CD133+ and VEGFR2+/CD34+) into the systemic circulation. Furthermore, under in vitro hyperglycemia and hypoxia conditions, PARP inhibition enhanced HUVEC migration and invasion in Boyden chamber assays by 80% and 180% (P < .05), respectively. CONCLUSIONS: Delayed healing in ischemic and diabetic wounds is caused by PARP hyperactivity, and PARP inhibition significantly enhanced ischemic and diabetic wound healing by promoting angiogenesis.


Assuntos
Indutores da Angiogênese/farmacologia , Diabetes Mellitus Experimental/complicações , Angiopatias Diabéticas/tratamento farmacológico , Isquemia/complicações , Neovascularização Fisiológica/efeitos dos fármacos , Fenantrenos/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Úlcera Cutânea/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Antígeno AC133/metabolismo , Animais , Antígenos CD34/metabolismo , Hipóxia Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Angiopatias Diabéticas/enzimologia , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/patologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/enzimologia , Glucose/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Isquemia/enzimologia , Isquemia/patologia , Masculino , Camundongos Knockout , Óxido Nítrico Sintase Tipo III/metabolismo , Poli(ADP-Ribose) Polimerase-1/deficiência , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Úlcera Cutânea/enzimologia , Úlcera Cutânea/etiologia , Úlcera Cutânea/patologia , Fatores de Tempo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
17.
J Hepatol ; 64(5): 1128-1136, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26767500

RESUMO

BACKGROUND & AIMS: Sepsis is an acute systemic inflammatory response to infection associated with high patient mortality (28-40%). We hypothesized that interleukin (IL)-30, a novel cytokine protecting mice against liver injury resulting from inflammation, would generate a protective effect against systemic inflammation and sepsis-induced death. METHODS: Sepsis was induced by lipopolysaccharide (LPS) or cecal ligation and puncture (CLP). The inhibitory effects of IL-30 on septic inflammation and associated therapeutic effects were determined in wild-type, IL30 (p28)(-/-), IL10(-/-), and CD1d(-/-) mice. RESULTS: Mice treated with pIL30 gene therapy or recombinant IL-30 protein (rIL30) were protected from LPS-induced septic shock or CLP-induced polymicrobial sepsis and showed markedly less liver damage and lymphocyte apoptosis than control septic mice. The resulting reduction in mortality was mediated through attenuation of the systemic pro-inflammatory response and augmentation of bacterial clearance. Mice lacking IL-30 were more sensitive to LPS-induced sepsis. Natural killer-like T cells (NKT) produced much higher levels of IL-10 and lower levels of interferon-gamma and tumor necrosis factor-alpha in IL-30-treated septic mice than in control septic mice. Likewise, deficiency in IL-10 or NKT cells abolished the protective role of IL-30 against sepsis. Furthermore, IL-30 induced IL-10 production in purified and LPS-stimulated NKT cells. Blocking IL-6R or gp130 inhibited IL-30 mediated IL-10 production. CONCLUSIONS: IL-30 is important in modulating production of NKT cytokines and subsequent NKT cell-mediated immune regulation of other cells. Therefore, IL-30 has a role in prevention and treatment of sepsis via modulation of cytokine production by NKT.


Assuntos
Citocinas/metabolismo , Interleucinas/farmacologia , Fígado/patologia , Células T Matadoras Naturais/imunologia , Choque Séptico/tratamento farmacológico , Animais , Citocinas/efeitos dos fármacos , Modelos Animais de Doenças , Citometria de Fluxo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Choque Séptico/metabolismo , Choque Séptico/patologia
19.
Gastrointest Endosc ; 84(2): 315-25, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26859866

RESUMO

BACKGROUND AND AIMS: Patients with complex colon polyps were traditionally referred for surgery to avoid adverse events associated with endoscopic resection. Recent advances in endoscopic imaging as well as endoscopic hemostasis and clip closure allow for the use of EMR as an alternative to surgery for such lesions. To determine the outcome of treatment of complex colon polyps with EMR as an alternative to surgery, we conducted a retrospective observational study. METHODS: Two hundred three patients with complex colon polyps were referred to an EMR center as an alternative to surgery. Patients underwent a protocol-driven EMR. The primary endpoint was the complete resection rate. Secondary endpoints were safety, residual adenoma rate, and incidence of missed synchronous polyps. RESULTS: EMR was performed in 155 patients and was deferred in 48 patients who were referred to surgery. EMR specimens revealed benign polyps in 149 and cancer in 6 patients. EMR adverse events occurred in 7 patients, requiring hospitalization in 5 of them. None of the patients died as a result of their adverse events. Surveillance colonoscopy at 4 to 6 months after resection of a benign lesion in 137 patients revealed residual adenoma at the scar site in 6 patients and additional synchronous precancerous lesions in 117 patients that were not removed by the referring endoscopist. None underwent surgery for failure of EMR. The overall precancerous lesion burden was 2.83 per patient, the adenoma burden was 2.13 per patient, and the serrated polyp burden was .69 per patient. CONCLUSIONS: EMR can be used instead of surgery for complex colon polyps in 75% of patients with few adverse events and few residual adenomas at resection sites. In addition, careful repeat examination of the entire colon for synchronous lesions overlooked by the referring endoscopist is required for most patients. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT01827241.).


Assuntos
Adenoma/cirurgia , Pólipos do Colo/cirurgia , Colonoscopia/métodos , Neoplasias Colorretais/cirurgia , Ressecção Endoscópica de Mucosa/métodos , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Colectomia , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos
20.
Biochim Biophys Acta ; 1846(1): 152-60, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24821201

RESUMO

Inflammation plays an integral part in tumor initiation. Specifically, patients with colitis, pancreatitis, or hepatitis have an increased susceptibility to cancer. The activation, mutation, and overexpression of oncogenes have been well documented in cell proliferation and transformation. Recently, oncogenes were found to also regulate the inflammatory milieu in tumors. Similarly, the inflammatory milieu can promote oncogene activation. In this review, we summarize advances of the symbiotic relationship oncogene activation and inflammation in gastrointestinal tumors such as colorectal, hepatic, and pancreatic tumors. NF-κB and STAT3 are the two most common pathways that are deregulated via these oncogenes. Understanding these interactions may yield effective therapeutic strategies for tumor prevention and treatment.


Assuntos
Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Inflamação/genética , Oncogenes/fisiologia , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/imunologia , Neoplasias Gastrointestinais/imunologia , Regulação Neoplásica da Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Permeabilidade , Transdução de Sinais/genética
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