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1.
Genes Dev ; 27(3): 288-300, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23355395

RESUMO

Pancreatic exocrine cell plasticity can be observed during development, pancreatitis with subsequent regeneration, and also transformation. For example, acinar-ductal metaplasia (ADM) occurs during acute pancreatitis and might be viewed as a prelude to pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDAC) development. To elucidate regulatory processes that overlap ductal development, ADM, and the progression of normal cells to PanIN lesions, we undertook a systematic approach to identify the Prrx1 paired homeodomain Prrx1 transcriptional factor as a highly regulated gene in these processes. Prrx1 annotates a subset of pancreatic ductal epithelial cells in Prrx1creER(T2)-IRES-GFP mice. Furthermore, sorted Prrx1(+) cells have the capacity to self-renew and expand during chronic pancreatitis. The two isoforms, Prrx1a and Prrx1b, regulate migration and invasion, respectively, in pancreatic cancer cells. In addition, Prrx1b is enriched in circulating pancreatic cells (Pdx1cre;LSL-Kras(G12D/+);p53(fl/+);R26YFP). Intriguingly, the Prrx1b isoform, which is also induced in ADM, binds the Sox9 promoter and positively regulates Sox9 expression. This suggests a new hierarchical scheme whereby a Prrx1-Sox9 axis may influence the emergence of acinar-ductal metaplasia and regeneration. Furthermore, our data provide a possible explanation of why pancreatic cancer is skewed toward a ductal fate.


Assuntos
Proteínas de Homeodomínio/metabolismo , Pâncreas/patologia , Pâncreas/fisiologia , Neoplasias Pancreáticas/fisiopatologia , Regeneração/fisiologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas/citologia , Regiões Promotoras Genéticas/genética , Ligação Proteica , Isoformas de Proteínas/metabolismo , Fatores de Transcrição SOX9/genética
2.
Development ; 143(1): 133-46, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26657772

RESUMO

Through their biased localization and function within the cell, polarity complex proteins are necessary to establish the cellular asymmetry required for tissue organization. Well-characterized germinal zones, mitogenic signals and cell types make the cerebellum an excellent model for addressing the crucial function of polarity complex proteins in the generation and organization of neural tissues. Deletion of the apical polarity complex protein Pals1 in the developing cerebellum results in a remarkably undersized cerebellum with disrupted layers in poorly formed folia and strikingly reduced granule cell production. We demonstrate that Pals1 is not only essential for cerebellum organogenesis, but also for preventing premature differentiation and thus maintaining progenitor pools in cerebellar germinal zones, including cerebellar granule neuron precursors in the external granule layer. In the Pals1 mouse mutants, the expression of genes that regulate the cell cycle was diminished, correlating with the loss of the proliferating cell population of germinal zones. Furthermore, enhanced Shh signaling through activated Smo cannot overcome impaired cerebellar cell generation, arguing for an epistatic role of Pals1 in proliferation capacity. Our study identifies Pals1 as a novel intrinsic factor that regulates the generation of cerebellar cells and Pals1 deficiency as a potential inhibitor of overactive mitogenic signaling.


Assuntos
Proliferação de Células/genética , Cerebelo/embriologia , Proteínas de Membrana/metabolismo , Neurogênese/fisiologia , Núcleosídeo-Fosfato Quinase/metabolismo , Células-Tronco/citologia , Animais , Ciclo Celular/genética , Cerebelo/citologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Neuroglia/citologia , Núcleosídeo-Fosfato Quinase/genética , Organogênese/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/genética , Receptor Smoothened
3.
Biochem Biophys Res Commun ; 501(3): 751-757, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29758193

RESUMO

Several aryl hydrocarbon receptor (AhR)-active pharmaceuticals were screened as inhibitors of pancreatic cancer cell invasion and identified two compounds, omeprazole, that inhibited invasion. Inhibition of highly invasive Panc1 cell invasion by omeprazole involves an AhR-dependent non-genomic pathway, and omeprazole-mediated inhibition of Panc1 cell invasion was dependent on Jun-N-terminal kinase (JNK) and mitogen-activated kinase kinase 7 (MKK7). The failure of omeprazole to induce nuclear translocation of the AhR was not due to overexpression of cytosolic AhR partner proteins Hsp90 or XAP2, and results of DNA sequencing show that the AhR expressed in Panc1 cells was not mutated. Results of RNAseq studies indicate that omeprazole induced an AhR-dependent downregulation of several pro-invasion factors including activated leukocyte cell adhesion molecule (ALCAM), long chain fatty acid CoA-synthase (CSL4), stathmin 3 (STMN3) and neuropillin 2 (NRP2), and the specific functions of these genes are currently being investigated.


Assuntos
Movimento Celular/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Invasividade Neoplásica/prevenção & controle , Omeprazol/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores da Bomba de Prótons/farmacologia , Receptores de Hidrocarboneto Arílico/metabolismo , Linhagem Celular Tumoral , Humanos , Invasividade Neoplásica/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia
4.
Gut ; 66(2): 215-225, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27507904

RESUMO

OBJECTIVE: Oesophageal squamous cell carcinoma (ESCC) is a heterogeneous disease with variable outcomes that are challenging to predict. A better understanding of the biology of ESCC recurrence is needed to improve patient care. Our goal was to identify small non-coding RNAs (sncRNAs) that could predict the likelihood of recurrence after surgical resection and to uncover potential molecular mechanisms that dictate clinical heterogeneity. DESIGN: We developed a robust prediction model for recurrence based on the analysis of the expression profile data of sncRNAs from 108 fresh frozen ESCC specimens as a discovery set and assessment of the associations between sncRNAs and recurrence-free survival (RFS). We also evaluated the mechanistic and therapeutic implications of sncRNA obtained through integrated analysis from multiple datasets. RESULTS: We developed a risk assessment score (RAS) for recurrence with three sncRNAs (microRNA (miR)-223, miR-1269a and nc886) whose expression was significantly associated with RFS in the discovery cohort (n=108). RAS was validated in an independent cohort of 512 patients. In multivariable analysis, RAS was an independent predictor of recurrence (HR, 2.27; 95% CI, 1.26 to 4.09; p=0.007). This signature implies the expression of ΔNp63 and multiple alterations of driver genes like PIK3CA. We suggested therapeutic potentials of immune checkpoint inhibitors in low-risk patients, and Polo-like kinase inhibitors, mammalian target of rapamycin (mTOR) inhibitors, and histone deacetylase inhibitors in high-risk patients. CONCLUSION: We developed an easy-to-use prognostic model with three sncRNAs as robust prognostic markers for postoperative recurrence of ESCC. We anticipate that such a stratified and systematic, tumour-specific biological approach will potentially contribute to significant improvement in ESCC treatment.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , MicroRNAs/análise , Recidiva Local de Neoplasia/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/cirurgia , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases , Intervalo Livre de Doença , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Feminino , Genômica , Inibidores de Histona Desacetilases/farmacologia , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Modelos Biológicos , Terapia de Alvo Molecular , Fosfatidilinositol 3-Quinases/genética , Valor Preditivo dos Testes , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Medição de Risco , Biologia de Sistemas , Serina-Treonina Quinases TOR/antagonistas & inibidores , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Quinase 1 Polo-Like
5.
J Cell Sci ; 128(16): 3055-67, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26208636

RESUMO

Megakaryocyte and erythroid development are tightly controlled by a repertoire of cytokines, but it is not clear how cytokine-activated signaling pathways are controlled during development of these two lineages. Here, we identify that expression of DLX4, a transcription factor encoded by a homeobox gene, increases during megakaryopoiesis but decreases during erythropoiesis. Enforced expression of DLX4 in CD34(+) stem and progenitor cells and in bipotent K562 cells induced lineage markers and morphologic features of megakaryocytes and repressed erythroid marker expression and hemoglobin levels. Converse results were obtained when DLX4 was knocked down. Gene Ontology and Gene Set Enrichment Analyses of genome-wide changes in gene expression revealed that DLX4 induces a megakaryocytic transcriptional program and inhibits an erythroid transcriptional program. DLX4 also induced gene signatures that are associated with nuclear factor κB (NF-κB) signaling. The ability of DLX4 to promote megakaryocyte development at the expense of erythroid generation was diminished by blocking NF-κB activity or by repressing IL1B, a transcriptional target of DLX4. Collectively, our findings indicate that DLX4 exerts opposing effects on the megakaryocytic and erythroid lineages in part by inducing IL-1ß and NF-κB signaling.


Assuntos
Diferenciação Celular/genética , Eritropoese/genética , Proteínas de Homeodomínio/biossíntese , Interleucina-1beta/genética , Células Progenitoras de Megacariócitos e Eritrócitos/citologia , Fatores de Transcrição/biossíntese , Linhagem da Célula/genética , Eritrócitos/citologia , Eritrócitos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Humanos , Interleucina-1beta/antagonistas & inibidores , Células K562 , Megacariócitos/citologia , Megacariócitos/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/genética
6.
Hepatology ; 63(1): 159-72, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26389641

RESUMO

UNLABELLED: Metabolic activation is a common feature of many cancer cells and is frequently associated with the clinical outcomes of various cancers, including hepatocellular carcinoma. Thus, aberrantly activated metabolic pathways in cancer cells are attractive targets for cancer therapy. Yes-associated protein 1 (YAP1) and transcriptional coactivator with PDZ-binding motif (TAZ) are oncogenic downstream effectors of the Hippo tumor suppressor pathway, which is frequently inactivated in many cancers. Our study revealed that YAP1/TAZ regulates amino acid metabolism by up-regulating expression of the amino acid transporters solute carrier family 38 member 1 (SLC38A1) and solute carrier family 7 member 5 (SLC7A5). Subsequently, increased uptake of amino acids by the transporters (SLC38A1 and SLC7A5) activates mammalian target of rapamycin complex 1 (mTORC1), a master regulator of cell growth, and stimulates cell proliferation. We also show that high expression of SLC38A1 and SLC7A5 is significantly associated with shorter survival in hepatocellular carcinoma patients. Furthermore, inhibition of the transporters and mTORC1 significantly blocks YAP1/TAZ-mediated tumorigenesis in the liver. These findings elucidate regulatory networks connecting the Hippo pathway to mTORC1 through amino acid metabolism and the mechanism's potential clinical implications for treating hepatocellular carcinoma. CONCLUSION: YAP1 and TAZ regulate cancer metabolism and mTORC1 through regulation of amino acid transportation, and two amino acid transporters, SLC38A1 and SLC7A5, might be important therapeutic targets.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Sistemas de Transporte de Aminoácidos/fisiologia , Carcinoma Hepatocelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neoplasias Hepáticas/metabolismo , Complexos Multiproteicos/fisiologia , Fosfoproteínas/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Carcinoma Hepatocelular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Fosfoproteínas/genética , Estrutura Terciária de Proteína , Transdução de Sinais , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP
7.
Chem Res Toxicol ; 28(5): 907-18, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25826687

RESUMO

Omeprazole and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) are aryl hydrocarbon receptor (AhR) agonists that inhibit the invasion of breast cancer cells through inhibition of CXCR4 transcription. Treatment of highly invasive Panc1 pancreatic cancer cells with TCDD, omeprazole, and seven other AhR-active pharmaceuticals showed that only omeprazole and tranilast, but not TCDD, inhibited invasion in a Boyden chamber assay. Similar results were observed in MiaPaCa2 cells, another quasimensenchymal pancreatic ductal adenocarcinoma (QM-PDA) pancreatic cancer cell line, whereas invasion was not observed with BxPC3 or L3.6pL cells, which are classified as classical (less invasive) pancreatic cancer cells. It was also observed in QM-PDA cells that TCDD, omeprazole, and tranilast did not induce CYP1A1 or CXCR4 and that treatment with these compounds did not result in nuclear uptake of AhR. In contrast, treatment of BxPC3 and L3.6pL cells with these AhR ligands resulted in induction of CYP1A1 (by TCDD) and nuclear uptake of AhR, which was similar to that observed for Ah-responsive MDA-MB-468 breast and HepG2 liver cancer cell lines. Results of AhR and AhR nuclear translocator (Arnt) knockdown experiments in Panc1 and MiaPaCa2 cells demonstrated that omeprazole- and tranilast-mediated inhibition of invasion was AhR-dependent but Arnt-independent. These results demonstrate that in the most highly invasive subtype of pancreatic cancer cells (QM-PDA) the selective AhR modulators omeprazole and tranilast inhibit invasion through a nongenomic AhR pathway.


Assuntos
Antineoplásicos/farmacologia , Invasividade Neoplásica/prevenção & controle , Omeprazol/farmacologia , Pâncreas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Citocromo P-450 CYP1A1/metabolismo , Feminino , Humanos , Invasividade Neoplásica/patologia , Pâncreas/patologia , Neoplasias Pancreáticas/patologia
9.
PLoS Med ; 11(12): e1001770, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25536056

RESUMO

BACKGROUND: Typically observed at 2 y after surgical resection, late recurrence is a major challenge in the management of hepatocellular carcinoma (HCC). We aimed to develop a genomic predictor that can identify patients at high risk for late recurrence and assess its clinical implications. METHODS AND FINDINGS: Systematic analysis of gene expression data from human liver undergoing hepatic injury and regeneration revealed a 233-gene signature that was significantly associated with late recurrence of HCC. Using this signature, we developed a prognostic predictor that can identify patients at high risk of late recurrence, and tested and validated the robustness of the predictor in patients (n = 396) who underwent surgery between 1990 and 2011 at four centers (210 recurrences during a median of 3.7 y of follow-up). In multivariate analysis, this signature was the strongest risk factor for late recurrence (hazard ratio, 2.2; 95% confidence interval, 1.3-3.7; p = 0.002). In contrast, our previously developed tumor-derived 65-gene risk score was significantly associated with early recurrence (p = 0.005) but not with late recurrence (p = 0.7). In multivariate analysis, the 65-gene risk score was the strongest risk factor for very early recurrence (<1 y after surgical resection) (hazard ratio, 1.7; 95% confidence interval, 1.1-2.6; p = 0.01). The potential significance of STAT3 activation in late recurrence was predicted by gene network analysis and validated later. We also developed and validated 4- and 20-gene predictors from the full 233-gene predictor. The main limitation of the study is that most of the patients in our study were hepatitis B virus-positive. Further investigations are needed to test our prediction models in patients with different etiologies of HCC, such as hepatitis C virus. CONCLUSIONS: Two independently developed predictors reflected well the differences between early and late recurrence of HCC at the molecular level and provided new biomarkers for risk stratification. Please see later in the article for the Editors' Summary.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/genética , Fatores de Risco , Fator de Transcrição STAT3/genética , Adulto Jovem
10.
Hepatology ; 58(1): 182-91, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23389994

RESUMO

UNLABELLED: Metabolic changes are common features of many cancer cells and are frequently associated with the clinical outcome of patients with various cancers, including hepatocellular carcinoma (HCC). Thus, aberrant metabolic pathways in cancer cells are attractive targets for cancer therapy. However, our understanding of cancer-specific regulatory mechanisms of cell metabolism is still very limited. We found that Tat-activating regulatory DNA-binding protein (TARDBP) is a novel regulator of glycolysis in HCC cells. TARDBP regulates expression of the platelet isoform of phosphofructokinase (PFKP), the rate-limiting enzyme of glycolysis that catalyzes the irreversible conversion of fructose-6-phosphate to fructose-1,6-bisphosphate. Silencing of TARDBP expression in multiple HCC cell lines leads to impaired glucose metabolism and inhibition of in vitro and in vivo growth of HCC cells. Notably, the microRNA 520 (miR-520) family is an intermediate regulator of TARDBP-mediated regulation of glycolysis. Mechanistically, TARDBP suppressed expression of the miR-520 family, which, in turn, inhibited expression of PFKP. We further showed that expression of TARDBP is significantly associated with the overall survival of patients with HCC. CONCLUSION: Our study provides new mechanistic insights into the regulation of glycolysis in HCC cells and reveals TARDBP as a potential therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Proteínas de Ligação a DNA/fisiologia , Neoplasias Hepáticas/fisiopatologia , MicroRNAs/fisiologia , Fosfofrutoquinase-1 Tipo C/genética , Animais , Plaquetas/enzimologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Feminino , Glicólise/efeitos dos fármacos , Glicólise/genética , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , MicroRNAs/antagonistas & inibidores
11.
Proc Natl Acad Sci U S A ; 108(42): 17456-61, 2011 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-21987811

RESUMO

Although the importance of the cellular microenvironment (soil) during invasion and metastasis of cancer cells (seed) has been well-recognized, technical challenges have limited the ability to assess the influence of the microenvironment on cancer cells at the molecular level. Here, we show that an experimental strategy, competitive cross-species hybridization of microarray experiments, can characterize the influence of different microenvironments on cancer cells by independently extracting gene expression data of cancer and host cells when human cancer cells were xenografted into different organ sites of immunocompromised mice. Surprisingly, the analysis of gene expression data showed that the brain microenvironment induces complete reprogramming of metastasized cancer cells, resulting in a gain of neuronal cell characteristics and mimicking neurogenesis during development. We also show that epigenetic changes coincide with transcriptional reprogramming in cancer cells. These observations provide proof of principle for competitive cross-species hybridization of microarray experiments to characterize the effect of the microenvironment on tumor cell behavior.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Animais , Astrócitos/metabolismo , Sequência de Bases , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Metilação de DNA , Primers do DNA/genética , DNA de Neoplasias/genética , Epigênese Genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Neurônios/metabolismo , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade da Espécie , Transcriptoma , Transplante Heterólogo , Microambiente Tumoral/genética
12.
Hepatology ; 55(5): 1443-52, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22105560

RESUMO

UNLABELLED: Clinical application of the prognostic gene expression signature has been delayed due to the large number of genes and complexity of prediction algorithms. In the current study we aimed to develop an easy-to-use risk score with a limited number of genes that can robustly predict prognosis of patients with hepatocellular carcinoma (HCC). The risk score was developed using Cox coefficient values of 65 genes in the training set (n = 139) and its robustness was validated in test sets (n = 292). The risk score was a highly significant predictor of overall survival (OS) in the first test cohort (P = 5.6 × 10(-5), n = 100) and the second test cohort (P = 5.0 × 10(-5) , n = 192). In multivariate analysis, the risk score was a significant risk factor among clinical variables examined together (hazard ratio [HR], 1.36; 95% confidence interval [CI], 1.13-1.64; P = 0.001 for OS). CONCLUSION: The risk score classifier we have developed can identify two clinically distinct HCC subtypes at early and late stages of the disease in a simple and highly reproducible manner across multiple datasets.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Perfilação da Expressão Gênica/classificação , Predisposição Genética para Doença/epidemiologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Área Sob a Curva , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Medição de Risco , Análise de Sobrevida , Adulto Jovem
13.
Helicobacter ; 18(2): 143-50, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23136938

RESUMO

BACKGROUND: Gastric cancer is supposed to be a result of inflammation induced by Helicobacter pylori (H. pylori) infection. Nucleotide-binding oligomerization domain 1 (NOD 1) is required for the innate immune response to H. pylori. We aim to investigate whether single nucleotide polymorphism (SNP) in NOD 1 gene is associated with H. pylori-induced gastric mucosal inflammation in a healthy Korean population. METHODS: The study was conducted on 412 adults who visited two different healthcare centers for health examinations. The G796A (E266K) NOD 1 SNP was detected by using polymerase chain reaction/restriction fragment length polymorphism. A gastritis score was calculated by the summed values of the grade and the activity of gastritis scored according to the updated Sydney system. The expression of IL-8 and COX-2 mRNA was assessed by quantitative reverse transcription polymerase chain reaction. In the group with H. pylori infection, the complete screening of the genes comprising the cag PAI was performed. RESULTS: The genotype frequencies were 26.7% (AA type), 58.3% (GA), and 15.0% (GG). In H. pylori-positive patients, gastritis score of the AA genotype was significantly higher than those of the others (p = .04). Also, the IL-8 and COX-2 mRNA levels increased in the AA genotype. In the group with H. pylori infection, 31.9% were found to carry the complete cag PAI. When the subjects were infected with intact cag PAI, the IL-8 and COX-2 mRNA levels were significantly high in AA genotype. CONCLUSION: G796A (E266K) NOD 1 polymorphism is closely correlated with H. pylori-associated gastric mucosal inflammation in the Korean population.


Assuntos
Povo Asiático/genética , Gastrite/genética , Predisposição Genética para Doença , Infecções por Helicobacter/genética , Proteína Adaptadora de Sinalização NOD1/genética , Polimorfismo Genético , Adulto , Idoso , Feminino , Gastrite/imunologia , Gastrite/microbiologia , Gastrite/patologia , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/fisiopatologia , Helicobacter pylori/patogenicidade , Humanos , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Adulto Jovem
14.
Gut ; 61(9): 1291-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21997556

RESUMO

AIMS: Despite continual efforts to develop prognostic and predictive models of colorectal cancer by using clinicopathological and genetic parameters, a clinical test that can discriminate between patients with good or poor outcome after treatment has not been established. Thus, the authors aim to uncover subtypes of colorectal cancer that have distinct biological characteristics associated with prognosis and identify potential biomarkers that best reflect the biological and clinical characteristics of subtypes. METHODS: Unsupervised hierarchical clustering analysis was applied to gene expression data from 177 patients with colorectal cancer to determine a prognostic gene expression signature. Validation of the signature was sought in two independent patient groups. The association between the signature and prognosis of patients was assessed by Kaplan-Meier plots, log-rank tests and the Cox model. RESULTS: The authors identified a gene signature that was associated with overall survival and disease-free survival in 177 patients and validated in two independent cohorts of 213 patients. In multivariate analysis, the signature was an independent risk factor (HR 3.08; 95% CI 1.33 to 7.14; p=0.008 for overall survival). Subset analysis of patients with AJCC (American Joint Committee on Cancer) stage III cancer revealed that the signature can also identify the patients who have better outcome with adjuvant chemotherapy (CTX). Adjuvant chemotherapy significantly affected disease-free survival in patients in subtype B (3-year rate, 71.2% (CTX) vs 41.9% (no CTX); p=0.004). However, such benefit of adjuvant chemotherapy was not significant for patients in subtype A. CONCLUSION: The gene signature is an independent predictor of response to chemotherapy and clinical outcome in patients with colorectal cancer.


Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante , Análise por Conglomerados , Estudos de Coortes , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
15.
Carcinogenesis ; 33(10): 1843-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22581827

RESUMO

Transcription factors are direct effectors of altered signaling pathways in cancer and frequently determine clinical outcomes in cancer patients. To uncover new transcription factors that would determine clinical outcomes in breast cancer, we systematically analyzed gene expression data from breast cancer patients. Our results revealed that Forkhead box protein M1 (FOXM1) is the top-ranked survival-associated transcription factor in patients with triple-negative breast cancer. Surprisingly, silencing FOXM1 expression led breast cancer cells to become more sensitive to doxorubicin (Dox). We found that FOXM1-dependent resistance to Dox is mediated by regulating DNA repair genes. We further demonstrated that NFκB1 interacts with FOXM1 in the presence of Dox to protect breast cancer cells from DNA damage. Finally, silencing FOXM1 expression in breast cancer cells in a mouse xenograft model significantly sensitized the cells to Dox. Our systematic approaches identified an unexpected role of FOXM1 in Dox resistance by regulating DNA repair genes, and our findings provide mechanistic insights into how FOXM1 mediates resistance to Dox and evidence that FOXM1 may be a promising therapeutic target for sensitizing breast cancer cells to Dox.


Assuntos
Neoplasias da Mama/genética , Reparo do DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição Forkhead/fisiologia , Fatores de Transcrição/fisiologia , Animais , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Transgênicos , Subunidade p50 de NF-kappa B/fisiologia , Prognóstico , Transplante Heterólogo
16.
Breast Cancer Res Treat ; 130(1): 155-64, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21833625

RESUMO

The aims of this study were to compare the performance of six different genomic prognostic markers to predict long-term survival and chemotherapy response on the same patient cohort and assess if clinicopathological variables carry independent prognostic and predictive values. We examined seven clinical variables and six previously described prognostic signatures on 228 tumors from patients who received homogeneous preoperative chemotherapy and had long-term follow-up information for survival. We used the area under the receiver operator characteristic curve (AUC) to compare predictors and also performed univariate and multivariate analyses including the genomic and clinical variables and plotted Kaplan-Meir survival curves. All genomic prognostic markers had statistically similar AUCs and sensitivity to predict 5-year progression-free survival (PFS, sensitivities ranged from 0.591 to 0.773, and AUCs: 0.599-0.673), overall survival (OS, sensitivities: 0.590-0.769, AUCs: 0.596-0.684) and pathologic complete response (pCR, sensitivities: 0.596-0.851, AUCs: 0.614-0.805). In multivariate analysis, the genomic markers were not independent from one another; however, estrogen receptor (Odds Ratio [OR] 7.63, P < 0.001) and HER2 status (OR: 0.37, P = 0.021) showed significant independent predictive values for pCR. Nodal status remained an independent prognostic, but not predictive, variable (OR for PFS: 2.77, P = 0.021, OR for OS: 3.62, P = 0.01). There was moderate to good agreement between different prediction results in pair-wise comparisons. First-generation prognostic-gene signatures predict both chemotherapy response and long-term survival. When multiple predictors are applied to the same case discordant risk prediction frequently occurs.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Risco , Resultado do Tratamento
17.
Opt Express ; 18(2): 1271-7, 2010 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-20173951

RESUMO

We have demonstrated that, in elevated oxide-layer vertical-cavity surface-emitting lasers (VCSELs) where the spacing between 1-lambda cavity and oxide layer is 9lambda/4, a variety of turn-off-induced abnormalities such as secondary pulsations, bumps and tails is effectively suppressed. Compared are turn-off transient responses of conventional and elevated oxide-layer VCSELs with the oxide-aperture diameter of approximately 6.6 microm. The "on"- and "off"-current dependence of the turn-off-induced transient responses and bit rate dependence of the timing jitters show that the elevated oxide-layer structure effectively suppresses the turn-off-induced pulsations to less than half of the conventional one, which enables the VCSEL transmitter to operate without deleterious effects by the turnoff-induced pulsation.


Assuntos
Artefatos , Lasers , Óxidos/química , Desenho de Equipamento , Análise de Falha de Equipamento
18.
Opt Express ; 17(7): 5147-52, 2009 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19333278

RESUMO

We have investigated low-current operation characteristics of a passively aligned VCSEL transmitter driven at fixed "on" and "off" current over a wide temperature range. GaAs/AlGaAs-based 850-nm oxide VCSELs with the minimum threshold current of 0.79 mA at 50 masculineC and small temperature dependence of the threshold current, d(2)I(th)/dT(2), as low as 0.114 muA/ masculineC(2) have been fabricated and used for the transmitter module. The superior temperature characteristics enable fixed-current operation of the VCSEL transmitter that complies with Gigabit Ethernet standard over a wide temperature range from -20 to 120 masculineC. This result paves the way to a VCSEL transmitter featured by low-power consumption, low-cost with a simple driving circuit and passive alignment, and a wide operation temperature range.


Assuntos
Lasers , Desenho Assistido por Computador , Fontes de Energia Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura
19.
Bioinformatics ; 23(13): 1697-9, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17468122

RESUMO

UNLABELLED: Gene Set Analyzer (GAzer) is a web-based integrated gene set analysis tool covering previously reported parametric and non-parametric models. Based on a simulation test for the reported algorithms, we classified and implemented three main statistical methods consisting of the z-statistic, gene permutation and sample permutation for ten gene set categories including Gene Ontology (GO) for human, mouse, rat and yeast. This tool identifies significantly altered gene sets scored by z-statistics and P-values from the z-test or permutation test and provides q-values and Bonferroni P-values to correct multiple hypothesis testing. GAzer allows users to observe changes in expression of each gene in a gene set or to see the significance of the gene sets containing a gene(s) of interest, thus allowing interactive data analysis both at the gene and gene set level. Moreover, GAzer offers extensive annotation for each gene. AVAILABILITY: The GAzer gene set analyzer is freely available at http://integromics.kobic.re.kr/GAzer/. SUPPLEMENTARY INFORMATION: This can be found on the web page (http://integromics.kobic.re.kr/GAzer/supplement.jsp).


Assuntos
Algoritmos , Perfilação da Expressão Gênica/métodos , Internet , Família Multigênica/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Software , Interface Usuário-Computador , Animais , Humanos , Camundongos , Ratos , Integração de Sistemas , Leveduras
20.
Mol Cancer Res ; 16(11): 1713-1723, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30082483

RESUMO

Hepatocellular carcinoma (HCC) is a heterogeneous disease. Mouse models are commonly used as preclinical models to study hepatocarcinogenesis, but how well these models recapitulate molecular subtypes of human HCC is unclear. Here, integration of genomic signatures from molecularly and clinically defined human HCC (n = 11) and mouse models of HCC (n = 9) identified the mouse models that best resembled subtypes of human HCC and determined the clinical relevance of each model. Mst1/2 knockout (KO), Sav1 KO, and SV40 T antigen mouse models effectively recapitulated subtypes of human HCC with a poor prognosis, whereas the Myc transgenic model best resembled human HCCs with a more favorable prognosis. The Myc model was also associated with activation of ß-catenin. E2f1, E2f1/Myc, E2f1/Tgfa, and diethylnitrosamine (DEN)-induced models were heterogeneous and were unequally split into poor and favorable prognoses. Mst1/2 KO and Sav1 KO models best resemble human HCC with hepatic stem cell characteristics. Applying a genomic predictor for immunotherapy, the six-gene IFNγ score, the Mst1/2 KO, Sav1 KO, SV40, and DEN models were predicted to be the least responsive to immunotherapy. Further analysis showed that elevated expression of immune-inhibitory genes (Cd276 and Nectin2/Pvrl2) in Mst1/2 KO, Sav1 KO, and SV40 models and decreased expression of immune stimulatory gene (Cd86) in the DEN model might be accountable for the lack of predictive response to immunotherapy.Implication: The current genomic approach identified the most relevant mouse models to human liver cancer and suggests immunotherapeutic potential for the treatment of specific subtypes. Mol Cancer Res; 16(11); 1713-23. ©2018 AACR.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas/genética , Animais , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Genômica/métodos , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Prognóstico
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