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1.
Pancreatology ; 22(7): 973-986, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35864067

RESUMO

BACKGROUND AND AIMS: Pancreatic cancer has a dismal prognosis. So far, imaging has been proven incapable of establishing an early enough diagnosis. Thus, biomarkers are urgently needed for early detection and improved survival. Our aim was to evaluate the pooled diagnostic performance of DNA alterations in pancreatic juice. METHODS: A systematic literature search was performed in EMBASE, MEDLINE Ovid, Cochrane CENTRAL and Web of Science for studies concerning the diagnostic performance of DNA alterations in pancreatic juice to differentiate patients with high-grade dysplasia or pancreatic cancer from controls. Study quality was assessed using QUADAS-2. The pooled prevalence, sensitivity, specificity and diagnostic odds ratio were calculated. RESULTS: Studies mostly concerned cell-free DNA mutations (32 studies: 939 cases, 1678 controls) and methylation patterns (14 studies: 579 cases, 467 controls). KRAS, TP53, CDKN2A, GNAS and SMAD4 mutations were evaluated most. Of these, TP53 had the highest diagnostic performance with a pooled sensitivity of 42% (95% CI: 31-54%), specificity of 98% (95%-CI: 92%-100%) and diagnostic odds ratio of 36 (95% CI: 9-133). Of DNA methylation patterns, hypermethylation of CDKN2A, NPTX2 and ppENK were studied most. Hypermethylation of NPTX2 performed best with a sensitivity of 39-70% and specificity of 94-100% for distinguishing pancreatic cancer from controls. CONCLUSIONS: This meta-analysis shows that, in pancreatic juice, the presence of distinct DNA mutations (TP53, SMAD4 or CDKN2A) and NPTX2 hypermethylation have a high specificity (close to 100%) for the presence of high-grade dysplasia or pancreatic cancer. However, the sensitivity of these DNA alterations is poor to moderate, yet may increase if they are combined in a panel.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Carcinoma Ductal Pancreático/diagnóstico , Detecção Precoce de Câncer , Mutação , Suco Pancreático/química , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas
2.
Gut Microbes ; 14(1): 2015238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34965181

RESUMO

Autophagy is a cellular degradation mechanism, which is triggered by the bacterium Helicobacter pylori. A single nucleotide polymorphism (SNP) in the autophagy gene ATG16L1 (rs2241880, G-allele) has been shown to dysregulate autophagy and increase intestinal endoplasmic reticulum (ER) stress. Here, we investigate the role of this SNP in H.pylori-mediated gastric carcinogenesis and its molecular pathways. ATG16L1 rs2241880 was genotyped in subjects from different ethnic cohorts (Dutch and Australian) presenting with gastric (pre)malignant lesions of various severity. Expression of GRP78 (a marker for ER stress) was assessed in gastric tissues. The effect of ATG16L1 rs2241880 on H.pylori-mediated ER stress and pro-inflammatory cytokine induction was investigated in organoids and CRISPR/Cas9 modified cell lines. Development of gastric cancer was associated with the ATG16L1 rs2241880 G-allele. Intestinal metaplastic cells in gastric tissue of patients showed increased levels of ER-stress. In vitro models showed that H.pylori increases autophagy while reducing ER stress, which appeared partly mediated by the ATG16L1 rs2241880 genotype. H.pylori-induced IL-8 production was increased while TNF-α production was decreased, in cells homozygous for the G-allele. The ATG16L1 rs2241880 G-allele is associated with progression of gastric premalignant lesions and cancer. Modulation of H.pylori-induced ER stress pathways and pro-inflammatory mediators by ATG16L1 rs2441880 may underlie this increased risk.


Assuntos
Autofagia , Estresse do Retículo Endoplasmático , Infecções por Helicobacter/fisiopatologia , Helicobacter pylori/fisiologia , Neoplasias Gástricas/fisiopatologia , Adulto , Idoso , Austrália , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Estudos de Coortes , Progressão da Doença , Feminino , Microbioma Gastrointestinal , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiologia
3.
Gastric Cancer ; 25(2): 375-381, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34792700

RESUMO

BACKGROUND: Gastric and colorectal cancer (CRC) are both one of the most common cancers worldwide. In many countries fecal immunochemical tests (FIT)-based CRC screening has been implemented. We investigated if FIT can also be applied for detection of H. pylori, the main risk factor for gastric cancer. METHODS: This prospective study included participants over 18 years of age referred for urea breath test (UBT). Patients were excluded if they had used antibiotics/bismuth in the past 4 weeks, or a proton pomp inhibitor (PPI) in the past 2 weeks. Participants underwent UBT, ELISA stool antigen test in standard feces tube (SAT), ELISA stool antigen test in FIT tube (Hp-FIT), and blood sampling, and completed a questionnaire on user friendliness. UBT results were used as reference. RESULTS: A total of 182 patients were included (37.4% male, median age 52.4 years (IQR 22.4)). Of these, 60 (33.0%) tested H. pylori positive. SAT and Hp-FIT showed comparable overall accuracy 71.1% (95%CI 63.2-78.3) vs. 77.6% (95%CI 70.4-83.8), respectively (p = 0.97). Sensitivity of SAT was 91.8% (95%CI 80.4-97.7) versus 94.2% (95%CI 84.1-98.9) of Hp-FIT (p = 0.98). Serology scored low with an overall accuracy of 49.7% (95%CI 41.7-57.7). Hp-FIT showed the highest overall user convenience. CONCLUSIONS: FIT can be used with high accuracy and sensitivity for diagnosis of H. pylori and is rated as the most convenient test. Non-invasive Hp-FIT test is highly promising for combined upper and lower gastrointestinal (pre-) cancerous screening. Further research should investigate the clinical implications, benefits and cost-effectiveness of such an approach.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Adolescente , Adulto , Fezes , Feminino , Infecções por Helicobacter/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
5.
Dis Esophagus ; 33(9)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129453

RESUMO

Barrett's esophagus (BE) is a metaplastic condition of the distal esophagus, resulting from longstanding gastroesophageal reflux disease (GERD). BE predisposes for the highly malignant esophageal adenocarcinoma (EAC). Both BE and EAC have the highest frequencies in white males. Only a subset of patients with GERD develop BE, while <0.5% of BE will progress to EAC. Therefore, it is most likely that the development of BE and EAC is associated with underlying genetic factors. We hypothesized that in white males, Y-chromosomal haplogroups are associated with BE and EAC. To investigate this we conducted a multicenter study studying the frequencies of the Y-chromosomal haplogroups in GERD, BE, and EAC patients. We used genomic analysis by polymerase chain reaction and restriction fragment length polymorphism to determine the frequency of six Y-chromosomal haplogroups (DE, F(xJ,xK), K(xP), J, P(xR1a), and R1a) between GERD, BE, and EAC in a cohort of 1,365 white males, including 612 GERD, 753 BE patients, while 178 of the BE patients also had BE-associated EAC. Univariate logistic regression analysis was used to compare the outcomes. In this study, we found the R1a (6% vs. 9%, P = 0.04) and K (3% vs. 6%, P = 0.035) to be significantly underrepresented in BE patients as compared to GERD patients with an odds ratio (OR) of 0.63 (95% CI 0.42-0.95, P = 0.03) and of 0.56 (95% CI 0.33-0.96, P = 0.03), respectively, while the K haplogroup was protective against EAC (OR 0.30; 95% CI 0.07-0.86, P = 0.05). A significant overrepresentation of the F haplogroup was found in EAC compared to BE and GERD patients (34% vs. 27% and 23%, respectively). The F haplogroup was found to be a risk factor for EAC with an OR of 1.5 (95% CI 1.03-2.19, P = 0.03). We identified the R1a and K haplogroups as protective factors against development of BE. These haplogroups have low frequencies in white male populations. Of importance is that we could link the presence of the predominantly occurring F haplogroup in white males to EAC. It is possible that this F haplogroup is associated to genetic variants that predispose for the EAC development. In future, the haplogroups could be applied to improve stratification of BE and GERD patients with increased risk to develop BE and/or EAC.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Cromossomos Humanos Y/genética , Neoplasias Esofágicas , Adenocarcinoma/genética , Esôfago de Barrett/genética , Cromossomos , Neoplasias Esofágicas/genética , Haplótipos , Humanos , Masculino , Fatores de Risco
6.
Colorectal Dis ; 22(1): 36-45, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344302

RESUMO

AIM: Anastomotic leakage (AL) is one of the most feared complications after rectal resection. This study aimed to assess a combination of biomarkers for early detection of AL after rectal cancer resection. METHOD: This study was an international multicentre prospective cohort study. All patients received a pelvic drain after rectal cancer resection. On the first three postoperative days drain fluid was collected daily and C-reactive protein (CRP) was measured. Matrix metalloproteinase-2 (MMP2), MMP9, glucose, lactate, interleukin 1-beta (IL1ß), IL6, IL10, tumour necrosis factor alpha (TNFα), Escherichia coli, Enterococcus faecalis, lipopolysaccharide-binding protein and amylase were measured in the drain fluid. Prediction models for AL were built for each postoperative day using multivariate penalized logistic regression. Model performance was estimated by the c-index for discrimination. The model with the best performance was visualized with a nomogram and calibration was plotted. RESULTS: A total of 292 patients were analysed; 38 (13.0%) patients suffered from AL, with a median interval to diagnosis of 6.0 (interquartile ratio 4.0-14.8) days. AL occurred less often after partial than after total mesorectal excision (4.9% vs 15.2%, P = 0.035). Of all patients with AL, 26 (68.4%) required reoperation. AL was more often treated by reoperation in patients without a diverting ileostomy (18/20 vs 8/18, P = 0.03). The prediction model for postoperative day 1 included MMP9, TNFα, diverting ileostomy and surgical technique (c-index = 0.71). The prediction model for postoperative day 2 only included CRP (c-index = 0.69). The prediction model for postoperative day 3 included CRP and MMP9 and obtained the best model performance (c-index = 0.78). CONCLUSION: The combination of serum CRP and peritoneal MMP9 may be useful for earlier prediction of AL after rectal cancer resection. In clinical practice, this combination of biomarkers should be interpreted in the clinical context as with any other diagnostic tool.


Assuntos
Fístula Anastomótica/etiologia , Líquido Ascítico/metabolismo , Protectomia/efeitos adversos , Neoplasias Retais/cirurgia , Medição de Risco/métodos , Biomarcadores/análise , Proteína C-Reativa/análise , Drenagem , Feminino , Humanos , Modelos Logísticos , Masculino , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Nomogramas , Peritônio/metabolismo , Período Pós-Operatório , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco
7.
United European Gastroenterol J ; 7(7): 897-907, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31428414

RESUMO

Background: Homeostasis of the gastrointestinal tract depends on a healthy bacterial microbiota, with alterations in microbiota composition suggested to contribute to diseases. To unravel bacterial contribution to disease pathology, a thorough understanding of the microbiota of the complete gastrointestinal tract is essential. To date, most microbial analyses have either focused on faecal samples, or on the microbial constitution of one gastrointestinal location instead of different locations within one individual. Objective: We aimed to analyse the mucosal microbiome along the entire gastrointestinal tract within the same individuals. Methods: Mucosal biopsies were taken from nine different sites in 14 individuals undergoing antegrade and subsequent retrograde double-balloon enteroscopy. The bacterial composition was characterised using 16 S rRNA sequencing with Illumina Miseq. Results: At double-balloon enteroscopy, one individual had a caecal adenocarcinoma and one individual had Peutz-Jeghers polyps. The composition of the microbiota distinctively changed along the gastrointestinal tract with larger bacterial load, diversity and abundance of Firmicutes and Bacteroidetes in the lower gastrointestinal tract than the upper gastrointestinal tract, which was predominated by Proteobacteria and Firmicutes. Conclusions: We show that gastrointestinal location is a larger determinant of mucosal microbial diversity than inter-person differences. These data provide a baseline for further studies investigating gastrointestinal microbiota-related disease.


Assuntos
Mucosa Gástrica/microbiologia , Microbioma Gastrointestinal , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Adulto , Carga Bacteriana , Biópsia , Neoplasias do Ceco/microbiologia , Neoplasias do Ceco/patologia , Enteroscopia de Duplo Balão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Peutz-Jeghers/microbiologia , Síndrome de Peutz-Jeghers/patologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de RNA
8.
Biochim Biophys Acta Rev Cancer ; 1872(2): 188291, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31059738

RESUMO

Idiopathic achalasia and Barrett's esophagus (BE) are preneoplastic conditions of the esophagus. BE increases the risk of esophageal adenocarcinoma (EAC), while achalasia is associated with both EAC and esophageal squamous cell carcinoma (ESCC). However, while the molecular mechanisms underlying the transformation of esophageal epithelial cells in BE are relatively well characterized, less is known regarding these processes in achalasia. Nevertheless, both conditions are associated with chronic inflammation and BE can occur in achalasia patients, and it is likely that similar processes underlie cancer risk in both diseases. The present review will discuss possible lessons that we can learn from the molecular analysis of BE for the study of achalasia-associated cancer and contrast findings in BE with those in achalasia. First, we will describe cellular fate during development of BE, EAC, and ESCC, and consider the inflammatory status of the epithelial barrier in BE and achalasia in terms of its contribution to carcinogenesis. Next, we will summarize current data on genetic alterations and molecular pathways involved in these processes. Lastly, the plausible role of the microbiota in achalasia-associated carcinogenesis and its contribution to abnormal lower esophageal sphincter (LES) functioning, the maintenance of chronic inflammatory status and influence on the esophageal mucosa through carcinogenic by-products, will be discussed.


Assuntos
Esôfago de Barrett/imunologia , Acalasia Esofágica/imunologia , Neoplasias Esofágicas/etiologia , Adenocarcinoma/etiologia , Adenocarcinoma/genética , Esôfago de Barrett/complicações , Esôfago de Barrett/genética , Progressão da Doença , Acalasia Esofágica/complicações , Acalasia Esofágica/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/etiologia , Carcinoma de Células Escamosas do Esôfago/genética , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Predisposição Genética para Doença , Humanos
9.
Best Pract Res Clin Gastroenterol ; 31(6): 607-618, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29566903

RESUMO

Advances in research techniques have made it possible to map the microbial communities in the gastrointestinal (GI) tract, where the majority of bacteria in the human body reside. Disturbances in these communities are referred to as dysbiosis and have been associated with GI cancers. Although dysbiosis is observed in several GI malignancies, the specific role of these changes has not been understood to the extent of Helicobacter pylori (HP) in gastric cancer (GC). This review will address the bacterial communities along the GI tract, from the oral cavity to the anal canal, particularly focusing on bacterial dysbiosis and carcinogenesis. Just as non-HP bacteria in the stomach may interact with HP in gastric carcinogenesis, the same may hold true for other GI tract malignancies, where an interplay between microbes in carcinogenesis seems conceivable, especially in colorectal cancer (CRC). In the last part of this review we will discuss the potential mechanisms of bacterial dysbiosis in GI carcinogenesis.


Assuntos
Carcinogênese/genética , Transformação Celular Neoplásica/genética , Microbioma Gastrointestinal/genética , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/microbiologia , Neoplasias Gastrointestinais/patologia , Humanos
10.
Mucosal Immunol ; 10(2): 352-360, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27435106

RESUMO

Thiopurines are commonly used drugs in the therapy of Crohn's disease, but unfortunately only show a 30% response rate. The biological basis for the thiopurine response is unclear, thus hampering patient selection prior to treatment. A genetic risk factor associated specifically with Crohn's disease is a variant in ATG16L1 that reduces autophagy. We have previously shown that autophagy is involved in dendritic cell (DC)-T-cell interactions and cytoskeletal regulation. Here we further investigated the role of autophagy in DC cytoskeletal modulation and cellular trafficking. Autophagy-deficient DC displayed loss of filopodia, altered podosome distribution, and increased membrane ruffling, all consistent with increased cellular adhesion. Consequently, autophagy-deficient DC showed reduced migration. The cytoskeletal aberrations were mediated through hyperactivation of Rac1, a known thiopurine target. Indeed thiopurines restored the migratory defects in autophagy-deficient DC. Clinically, the ATG16L1 risk variant associated with increased response to thiopurine treatment in patients with Crohn's disease but not ulcerative colitis. These results suggest that the association between ATG16L1 and Crohn's disease is mediated at least in part through Rac1 hyperactivation and subsequent defective DC migration. As this phenotype can be corrected using thiopurines, ATG16L1 genotyping may be useful in the identification of patients that will benefit most from thiopurine treatment.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Doença de Crohn/imunologia , Células Dendríticas/fisiologia , Proteínas rac1 de Ligação ao GTP/metabolismo , Alelos , Animais , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Estruturas da Membrana Celular/patologia , Movimento Celular , Células Cultivadas , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/genética , Citoesqueleto/metabolismo , Células Dendríticas/patologia , Feminino , Predisposição Genética para Doença , Humanos , Mercaptopurina/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Polimorfismo Genético , RNA Interferente Pequeno/genética , Risco
11.
Mol Ther Nucleic Acids ; 5: e350, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28131248

RESUMO

A subset of pancreatic cystic neoplasms are regarded as precursor lesions of pancreatic cancer, but only a minority of all pancreatic cystic neoplasms will undergo malignant transformation. MicroRNAs are increasingly recognized as molecular targets in carcinogenesis. Previously, a 9-microRNA (miR) signature was suggested to discriminate between high risk and low risk pancreatic cystic neoplasm. In this study, we aimed to validate this 9-miR panel in a prospective cohort. Total miR was isolated from pancreatic cyst fluid and expression of miR18a, miR24, miR30a-3p, miR92a, miR99b, miR106b, miR142-3p, miR342-3p, and miR532-3p was analyzed by singleplex Taqman MicroRNA Assay. A total of 62 patient samples were analyzed. During follow-up, 24 (38.7%) patients underwent resection, of which 6 (9.7%) patients showed at least high grade dysplasia. A logistic regression model presented a "predicted risk" score which significantly differed between low and high risk cysts, either including all patients or only those with histological confirmation of diagnosis. Using a set cut-off of 50%, the sensitivity of the model for the total cohort was 10.0%, specificity 100.0%, positive predicted value 100.0%, negative predicted value 85.2%, and diagnostic accuracy of 85.5%. Thus, while observing a significant difference between low and high risk cysts, clinical implementation of this biomarker panel is as yet unlikely to be beneficial in the management of pancreatic cysts.

12.
J Viral Hepat ; 23(4): 294-304, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26620360

RESUMO

Hepatitis E virus (HEV) represents one of the foremost causes of acute hepatitis globally. Although there is no proven medication for hepatitis E, pegylated interferon-α (IFN-α) has been used as off-label drug for treating HEV. However, the efficacy and molecular mechanisms of how IFN signalling interacts with HEV remain undefined. As IFN-α has been approved for treating chronic hepatitis C (HCV) for decades and the role of interferon signalling has been well studied in HCV infection, this study aimed to comprehensively investigate virus-host interactions in HEV infection with focusing on the IFN signalling, in comparison with HCV infection. A comprehensive screen of human cytokines and chemokines revealed that IFN-α was the sole humoral factor inhibiting HEV replication. IFN-α treatment exerted a rapid and potent antiviral activity against HCV, whereas it had moderate and delayed anti-HEV effects in vitro and in patients. Surprisingly, blocking the basal IFN pathway by inhibiting JAK1 to phosphorylate STAT1 has resulted in drastic facilitation of HEV, but not HCV infection. Gene silencing of the key components of JAK-STAT cascade of the IFN signalling, including JAK1, STAT1 and interferon regulatory factor 9 (IRF9), stimulated HEV infection. In conclusion, compared to HCV, HEV is less sensitive to IFN treatment. In contrast, the basal IFN cascade could effectively restrict HEV infection. This bears significant implications in management of HEV patients and future therapeutic development.


Assuntos
Vírus da Hepatite E/imunologia , Hepatite E/patologia , Hepatite E/terapia , Interações Hospedeiro-Patógeno , Interferon-alfa/metabolismo , Antivirais/metabolismo , Antivirais/uso terapêutico , Linhagem Celular Tumoral , Hepatite C Crônica/patologia , Hepatite C Crônica/terapia , Vírus da Hepatite E/fisiologia , Hepatócitos/virologia , Humanos , Interferon-alfa/uso terapêutico , Replicação Viral
13.
Br J Cancer ; 112(1): 122-30, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25393365

RESUMO

BACKGROUND: Constitutive Wnt activation is essential for colorectal cancer (CRC) initiation but also underlies the cancer stem cell phenotype, metastasis and chemosensitivity. Importantly Wnt activity is still modulated as evidenced by higher Wnt activity at the invasive front of clonal tumours termed the ß-catenin paradox. SMAD4 and p53 mutation status and the bone morphogenetic protein (BMP) pathway are known to affect Wnt activity. The combination of SMAD4 loss, p53 mutations and BMP signalling may integrate to influence Wnt signalling and explain the ß-catenin paradox. METHODS: We analysed the expression patterns of SMAD4, p53 and ß-catenin at the invasive front of CRCs using immunohistochemistry. We activated BMP signalling in CRC cells in vitro and measured BMP/Wnt activity using luciferase reporters. MTT assays were performed to study the effect of BMP signalling on CRC chemosensitivity. RESULTS: Eighty-four percent of CRCs with high nuclear ß-catenin staining are SMAD4 negative and/or p53 aberrant. BMP signalling inhibits Wnt signalling in CRC only when p53 and SMAD4 are unaffected. In the absence of SMAD4, BMP signalling activates Wnt signalling. When p53 is lost or mutated, BMP signalling no longer influences Wnt signalling. The cytotoxic effects of 5-FU are influenced in a similar manner. CONCLUSIONS: The BMP signalling pathway differentially modulates Wnt signalling dependent on the SMAD4 and p53 status. The use of BMPs in cancer therapy, as has been proposed by previous studies, should be targeted to individual cancers based on the mutational status of p53 and SMAD4.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Neoplasias Colorretais/metabolismo , Proteína Smad4/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt , Proteínas Morfogenéticas Ósseas/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Transdução de Sinais , Transfecção , Proteína Supressora de Tumor p53/genética , beta Catenina/genética , beta Catenina/metabolismo
14.
Oncogene ; 34(39): 5055-68, 2015 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25531314

RESUMO

Further understanding of the molecular biology and pathogenesis of hepatocellular carcinoma (HCC) is crucial for future therapeutic development. SMAD4, recognized as an important tumor suppressor, is a central mediator of transforming growth factor beta (TGFB) and bone morphogenetic protein (BMP) signaling. This study investigated the role of SMAD4 in HCC. Nuclear localization of SMAD4 was observed in a cohort of 140 HCC patients using tissue microarray. HCC cell lines were used for functional assay in vitro and in immune-deficient mice. Nuclear SMAD4 levels were significantly increased in patient HCC tumors as compared with adjacent tissues. Knockdown of SMAD4 significantly reduced the efficiency of colony formation and migratory capacity of HCC cells in vitro and was incompatible with HCC tumor initiation and growth in mice. Knockdown of SMAD4 partially conferred resistance to the anti-growth effects of BMP ligand in HCC cells. Importantly, simultaneous elevation of SMAD4 and phosphorylated SMAD2/3 is significantly associated with poor patient outcome after surgery. Although high levels of SMAD4 can also mediate an antitumor function by coupling with phosphorylated SMAD1/5/8, this signaling, however, is absent in majority of our HCC patients. In conclusion, this study revealed a highly non-canonical tumor-promoting function of SMAD4 in HCC. The drastic elevation of nuclear SMAD4 in sub-population of HCC tumors highlights its potential as an outcome predictor for patient stratification and a target for personalized therapeutic development.


Assuntos
Carcinogênese , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteína Smad4/fisiologia , Animais , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Camundongos , Fosforilação , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad4/genética
15.
Aliment Pharmacol Ther ; 40(10): 1202-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25263077

RESUMO

BACKGROUND: Adalimumab is an effective therapy for Crohn's disease patients. However, there is limited knowledge on the pharmacokinetic properties of adalilumab in patients with Crohn's disease. AIM: To assess the pharmacokinetic properties of adalilumab in a retrospective clinical cohort of patients with Crohn's disease, naïve to anti-tumour necrosis factor alpha therapy (anti-TNF). METHODS: In a single tertiary centre, a clinical retrospective cohort was formed out of 76 patients with Crohn's disease who started adalilumab treatment (160/80/40EOW) between July 2007 and September 2010. We serially evaluated adalilumab serum levels at week 0, 12 and 28. RESULTS: Patients were followed for a median time of 201 days (range 120-244) and received a median of 14 adalilumab injections (range 6-25). Adalilumab levels, although divergent between patients, were stable between week 12 and week 28. There was no correlation between adalilumab level and time since last administration (r = -0.061). In a multivariable regression analysis of patient factors influencing week 28 adalilumab levels, the regression model containing CRP at week 28 and BMI at baseline weakly but significantly predicted week 28 adalilumab levels (R(2) = 0.193, P = 0.004). Concomitant use of immunosuppressives was not a significant predictor (P = 0.304). CONCLUSIONS: Intra-individual adalilumab levels seem very stable during the first 28 weeks of treatment, whereas inter-individual levels vary. Adalilumab levels appear stable over a 2-week period, as the time since last adalilumab administration did not affect the adalilumab level. CRP and BMI weakly predict week 28 adalilumab levels, whereas the use of immunosuppressives does not.


Assuntos
Anti-Inflamatórios/farmacocinética , Anticorpos Monoclonais Humanizados/farmacocinética , Doença de Crohn/sangue , Adalimumab , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Índice de Massa Corporal , Proteína C-Reativa/análise , Doença de Crohn/tratamento farmacológico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto Jovem
16.
Cancer Treat Rev ; 40(4): 513-22, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24315741

RESUMO

Traditional chemotherapeutics have largely failed to date to produce significant improvements in pancreatic cancer survival. One of the reasons for the resilience of pancreatic cancer towards intensive treatment is that the cancer is capable of high jacking the immune system: during disease progression the immune system is converted from a system that attacks tumor cells into a support structure for the cancer, exerting trophic actions on the cancer cells. This turn-around of immune system action is achieved through mobilization and activation of regulatory T cells, myeloid derived suppressor cells, tumor-associated macrophages and fibroblasts, all of which suppress CD8 T cells and NK cells. This immune suppression occurs both through the expression of tolerance-inducing cell surface molecules, such as PD-L1, as well as through the production of "tolerogenic" cytokines, such as IL-10 and TGF-ß. Based on the accumulating insight into the importance of the immune system for the outcome of pancreatic cancer patients multiple new immunotherapeutic approaches against pancreatic cancer are being currently tested in clinical trials. In this review we give an overview of both the immune escaping mechanisms of pancreatic cancer as well as the new immune related therapeutic strategies currently being tested in pancreatic cancer clinical trials.


Assuntos
Imunoterapia/métodos , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/terapia , Animais , Citocinas/imunologia , Progressão da Doença , Humanos , Imunidade Celular/imunologia , Neoplasias Pancreáticas/patologia
17.
Leukemia ; 28(3): 589-99, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24240200

RESUMO

Single kinase-targeted cancer therapies often failed prolonged responses because cancer cells bypass through alternative routes. In this study, high-throughput kinomic and proteomic approaches enabled to identify aberrant activity profiles in mixed lineage leukemia (MLL)-rearranged acute myeloid leukemia (AML) that defined druggable targets. This approach revealed impaired activity of proteins belonging to the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathway. Pharmacological druggable MAPK pathway targets tested in primary MLL-rearranged AML included MAPKK1/2 (MEK), cyclic AMP-responsive element-binding protein (CREB) and MAPK8/9 (JNK). MEK inhibition showed to severely decrease MLL-rearranged AML cell survival without showing cytotoxicity in normal controls, whereas inhibition of CREB and JNK failed to exhibit MLL selectivity. Exploring the working mechanism of MEK inhibition, we assessed proteome activity in response to MEK inhibition in THP-1. MAPK1/3 (Erk) phosphorylation was instantly decreased in concurrence with a sustained Akt/mammalian target of rapamycin (mTOR) phosphorylation that enabled a subpopulation of cells to survive MEK inhibition. After exhaustion of MEK inhibition the AML cells recovered via increased activity of vascular endothelial growth factor receptor-2 (VEGFR-2) and Erk proteins to resume their proliferative state. Combined MEK and VEGFR-2 inhibition strengthened the reduction in MLL-rearranged AML cell survival by blocking the Akt/mTOR and MAPK pathways simultaneously. The generation of insights in cancerous altered activity profiles and alternative escape mechanisms upon targeted therapy allows the rational design of novel combination strategies.


Assuntos
Rearranjo Gênico , Leucemia Mieloide Aguda/enzimologia , MAP Quinase Quinase Quinases/antagonistas & inibidores , Fosfotransferases/metabolismo , Linhagem Celular Tumoral , Histona-Lisina N-Metiltransferase , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
18.
Sci Rep ; 3: 2173, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23838847

RESUMO

Adipocytes hypertrophy is the main cause of obesity and its affliction such as type 2 diabetes (T2D). Since superparamagnetic iron oxide nanoparticles (SPIONs) are used for a wide range of biomedical/medical applications, we aimed to study the effect of SPIONs on 22 and 29 risk genes (Based on gene wide association studies) for obesity and T2D in human adipocytes. The mRNA expression of lipid and glucose metabolism genes was changed upon the treatment of human primary adipocytes with SPIONs. mRNA of GULP1, SLC30A8, NEGR1, SEC16B, MTCH2, MAF, MC4R, and TMEM195 were severely induced, whereas INSIG2, NAMPT, MTMR9, PFKP, KCTD15, LPL and GNPDA2 were down-regulated upon SPIONs stimulation. Since SEC16B gene assist the phagocytosis of apoptotic cells and this gene were highly expressed upon SPIONs treatment in adipocytes, it is logic to assume that SPIONs may play a crucial role in this direction, which requires more consideration in the future.


Assuntos
Adipócitos/efeitos dos fármacos , Diabetes Mellitus Tipo 2/genética , Compostos Férricos/farmacologia , Expressão Gênica/efeitos dos fármacos , Predisposição Genética para Doença , Magnetismo , Obesidade/genética , Adipócitos/metabolismo , Compostos Férricos/química , Humanos , Microscopia Eletrônica de Transmissão
19.
Biochim Biophys Acta ; 1835(2): 194-210, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23287572

RESUMO

The serine/threonine kinase LKB1 is a master kinase involved in cellular responses such as energy metabolism, cell polarity and cell growth. LKB1 regulates these crucial cellular responses mainly via AMPK/mTOR signaling. Germ-line mutations in LKB1 are associated with the predisposition of the Peutz-Jeghers syndrome in which patients develop gastrointestinal hamartomas and have an enormously increased risk for developing gastrointestinal, breast and gynecological cancers. In addition, somatic inactivation of LKB1 has been associated with sporadic cancers such as lung cancer. The exact mechanisms of LKB1-mediated tumor suppression remain so far unidentified; however, the inability to activate AMPK and the resulting mTOR hyperactivation has been detected in PJS-associated lesions. Therefore, targeting LKB1 in cancer is now mainly focusing on the activation of AMPK and inactivation of mTOR. Preclinical in vitro and in vivo studies show encouraging results regarding these approaches, which have even progressed to the initiation of a few clinical trials. In this review, we describe the functions, regulation and downstream signaling of LKB1, and its role in hereditary and sporadic cancers. In addition, we provide an overview of several AMPK activators, mTOR inhibitors and additional mechanisms to target LKB1 signaling, and describe the effect of these compounds on cancer cells. Overall, we will explain the current strategies attempting to find a way of treating LKB1-associated cancer.


Assuntos
Neoplasias/tratamento farmacológico , Proteínas Serina-Treonina Quinases/fisiologia , Transdução de Sinais/fisiologia , Quinases Proteína-Quinases Ativadas por AMP , Animais , Polaridade Celular , Humanos , Metformina/farmacologia , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
20.
Dis Esophagus ; 26(2): 130-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22458661

RESUMO

Clinicians and basic researchers worldwide convened at the annual Digestive Disease Week where the latest research in the field of gastroenterology and hepatology is presented. In this report, the highlights of the convention on the field of Barrett's esophagus (BE) and associated esophageal adenocarcinoma (EAC) are summarized. New clinical and preclinical developments in etiology, diagnosis, surveillance, and prevention and therapy of BE and EAC in respect to current knowledge are reflected. We also discuss the relevance and impact of these findings on the future of BE and EAC research.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Neoplasias Esofágicas , Adenocarcinoma/diagnóstico , Adenocarcinoma/etiologia , Adenocarcinoma/metabolismo , Adenocarcinoma/terapia , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/etiologia , Esôfago de Barrett/metabolismo , Esôfago de Barrett/terapia , Biomarcadores/metabolismo , Biópsia , Progressão da Doença , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/terapia , Esofagectomia , Esofagoscopia , Esôfago/patologia , Fármacos Gastrointestinais/uso terapêutico , Humanos , Fatores de Risco
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