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As obesity rates continue to rise, the prevalence of metabolic dysfunction and alcohol-associated steatotic liver disease (MetALD), a new term for Nonalcoholic Fatty Liver Disease (NAFLD), also increases. In an aging population, it is crucial to understand the interplay between metabolic disorders, such as MetALD, and bone health. This understanding becomes particularly significant in the context of implant osseointegration. This study introduces an in vitro model simulating high lipogenesis through the use of human Mesenchymal Stroma Cells-derived adipocytes, 3D intrahepatic cholangiocyte organoids (ICO), and Huh7 hepatocytes, to evaluate the endocrine influence on osteoblasts interacting with titanium. We observed a significant increase in intracellular fat accumulation in all three cell types, along with a corresponding elevation in metabolic gene expression compared to the control groups. Notably, osteoblasts undergoing mineralization in this high-lipogenesis environment also displayed lipid vesicle accumulation. The study further revealed that titanium surfaces modulate osteogenic gene expression and impact cell cycle progression, cell survival, and extracellular matrix remodeling under lipogenic conditions. These findings provide new insights into the challenges of implant integration in patients with obesity and MetALD, offering a deeper understanding of the metabolic influences on bone regeneration and implant success.
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Lipogênese , Osteogênese , Titânio , Humanos , Titânio/farmacologia , Osteogênese/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Adipócitos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Osteoblastos/efeitos dos fármacos , Organoides/metabolismo , Hepatócitos/metabolismoRESUMO
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.
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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 PancreáticasRESUMO
BACKGROUND: Surveillance of individuals at risk of developing pancreatic ductal adenocarcinoma (PDAC) has the potential to improve survival, yet early detection based on solely imaging modalities is challenging. We aimed to identify changes in serum glycosylation levels over time to earlier detect PDAC in high-risk individuals. METHODS: Individuals with a hereditary predisposition to develop PDAC were followed in two surveillance programs. Those, of which at least two consecutive serum samples were available, were included. Mass spectrometry analysis was performed to determine the total N-glycome for each consecutive sample. Potentially discriminating N-glycans were selected based on our previous cross-sectional analysis and relative abundances were calculated for each glycosylation feature. RESULTS: 165 individuals ("FPC-cohort" N = 119; Leiden cohort N = 46) were included. In total, 97 (59%) individuals had a genetic predisposition (77 CDKN2A, 15 BRCA1/2, 5 STK11) and 68 (41%) a family history of PDAC without a known genetic predisposition (>10-fold increased risk of developing PDAC). From each individual, a median number of 3 serum samples (IQR 3) was collected. Ten individuals (6%) developed PDAC during 35 months of follow-up; nine (90%) of these patients carried a CDKN2A germline mutation. In PDAC cases, compared to all controls, glycosylation characteristics were increased (fucosylation, tri- and tetra-antennary structures, specific sialic linkage types), others decreased (complex-type diantennary and bisected glycans). The largest change over time was observed for tri-antennary fucosylated glycans, which were able to differentiate cases from controls with a specificity of 92%, sensitivity of 49% and accuracy of 90%. CONCLUSION: Serum N-glycan monitoring may support early detection in a pancreas surveillance program.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Proteínas Sanguíneas/genética , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Estudos Transversais , Detecção Precoce de Câncer , Predisposição Genética para Doença , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Polissacarídeos/metabolismo , Neoplasias PancreáticasRESUMO
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.
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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/microbiologiaRESUMO
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.
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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 EspecificidadeRESUMO
BACKGROUND: Transanal advancement flap repair of transsphincteric fistulas is a sphincter-preserving procedure, which frequently fails, probably due to ongoing inflammation in the remaining fistula tract. Adipose-derived stromal vascular fraction (SVF) has immunomodulatory properties promoting wound healing and suppressing inflammation. Platelet-rich plasma (PRP) reinforces this biological effect. The aim of this study was to evaluate the efficacy and safety of autologous adipose-derived SVF enriched with PRP in flap repair of transsphincteric cryptoglandular fistulas. METHODS: A prospective cohort study was conducted including consecutive patients with transsphincteric cryptoglandular fistula in a tertiary referral center. During flap repair, SVF was obtained by lipoharvesting and mechanical fractionation of adipose tissue and combined with PRP was injected around the internal opening and into the fistulous wall. Endpoints were fistula healing at clinical examination and fistula closure on postoperative magnetic resonance imaging (MRI). Adverse events were documented. RESULTS: Forty-five patients with transsphincteric cryptoglandular fistula were included (29 males, median age 44 years [range 36-53 years]). In the total study population, primary fistula healing was observed in 38 patients (84%). Among the 42 patients with intestinal continuity at time of surgery, primary fistula healing was observed in 35 patients (84%). In one patient, the fistula recurred, resulting in a long-term healing rate of 82%. MRI, performed in 37 patients, revealed complete closure of the fistula tract in 33 (89.2%). In the other patients, the tract was almost completely obliterated by scar tissue. During follow-up, none of these patients showed clinical signs of recurrence. The postoperative course was uneventful, except for three cases; venous thromboembolism in one patient and bleeding under the flap, necessitating intervention in two patients. CONCLUSIONS: Addition of autologous SVF enriched with PRP during flap repair is feasible, safe and might improve outcomes in patients with a transsphincteric cryptoglandular fistula. TRIAL REGISTRATION: Dutch Trial Register, Trial Number: NL8416, https://www.trialregister.nl/.
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Plasma Rico em Plaquetas , Fístula Retal , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fístula Retal/cirurgia , Fração Vascular Estromal , Resultado do TratamentoRESUMO
Objectives: The effect of pregnaSSncy on the course of inflammatory bowel disease (IBD) remains controversial. We aimed to describe the disease course before and after a first pregnancy in IBD patients.Methods: We analyzed data from a prospectively followed-up pregnancy cohort (minimal follow-up of 7 years), with clinical, biochemical and endoscopic characteristics obtained pre-pregnancy, during pregnancy and post-pregnancy. Possible factors associated with relapse (disease activity during pregnancy, maternal age, smoking, alcohol use, pre-pregnancy BMI, mode of delivery, thiopurine use during pregnancy, biological use during pregnancy, combination of thiopurine and biological use during pregnancy, breastfeeding, IBD diagnosis, endoscopic scores) were scored.Results: One hundred twenty six patients (95 Crohn's Disease [CD; 75%] and 31 Ulcerative Colitis/IBD unclassified [UC/IBD-U; 25%]) were enrolled, with one hundred pregnancies occurring in 100 primigravida patients. All pregnancies resulted in live birth. Twenty patients (20%) had a relapse during pregnancy. The median number of relapses/patient/year was 0.25 (IQR 0.5) and 0 (IQR 0.43) respectively before and after pregnancy (p = .00). For CD patients the median relapses/person/year was 0.25 (IQR 0.5) before and 0 (IQR 0.25) after delivery (p = .00), for UC/IBD-U patients there was no significant difference. In the post-partum period more UC patients relapsed compared to CD patients (68% vs 30.7%, p = .01). Seven-year IBD-course was unchanged in the 26 women who did not become pregnant.Conclusion: In this prospective observational cohort study, we found a lower rate of relapses in the 4 years after delivery compared to the 3 years prior to a first pregnancy. Post-partum, more UC patients experienced a relapse compared to CD patients.
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Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Estudos de Coortes , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Feminino , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Gravidez , Estudos ProspectivosRESUMO
Background and study aims Gastric cancer (GC) is usually preceded by premalignant gastric lesions (GPLs) such as gastric intestinal metaplasia (GIM). Information on risk factors associated with neoplastic progression of GIM are scarce. This study aimed to identify predictors for progression of GIM in areas with low GC incidence. Patients and methods The Progression and Regression of Precancerous Gastric Lesions (PROREGAL) study includes patients with GPL. Patients underwent at least two upper endoscopies with random biopsy sampling. Progression of GIM means an increase in severity according to OLGIM (operative link on gastric intestinal metaplasia) during follow-up (FU). Family history and lifestyle factors were determined through questionnaires. Serum Helicobacter pylori infection, pepsinogens (PG), gastrin-17 and GC-associated single nucleotide polymorphisms (SNPs) were determined. Cox regression was performed for risk analysis and a chi-squared test for analysis of single nucleotide polymorphisms. Results Three hundred and eight patients (median age at inclusion 61 years, interquartile range (IQR: 17; male 48.4â%; median FU 48 months, IQR: 24) were included. During FU, 116 patients (37.7â%) showed progression of IM and six patients (1.9â%) developed high-grade dysplasia or GC. The minor allele (C) on TLR4 (rs11536889) was inversely associated with progression of GIM (OR 0.6; 95â%CI 0.4-1.0). Family history (HR 1.5; 95â%CI 0.9-2.4) and smoking (HR 1.6; 95â%CI 0.9-2.7) showed trends towards progression of GIM. Alcohol use, body mass index, history of H. pylori infection, and serological markers were not associated with progression. Conclusions Family history and smoking appear to be related to an increased risk of GIM progression in low GC incidence countries. TLR4 (rs11536889) showed a significant inverse association, suggesting that genetic information may play a role in GIM progression.
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BACKGROUND: Epidemiological studies and meta-analyses show an association between statin use and a reduced incidence of colorectal cancer (CRC). We have shown that statins act on CRC through bone morphogenetic protein (BMP) signalling, but the exact cellular targets and underlying mechanism of statin action remain elusive. In this study, we set out to assess the influence of statins on global cancer cell signalling by performing an array-based kinase assay using immobilised kinase substrates spanning the entire human kinome. METHODS: CRC cells with or without Lovastatin treatment were used for kinome analysis. Findings on kinome arrays were further confirmed by immunoblotting with activity-specific antibodies. Experiments in different CRC cell lines using immunoblotting, siRNA-mediated knockdown and treatment with specific BMP inhibitor Noggin were performed. The relevance of in vitro findings was confirmed in xenografts and in CRC patients treated with Simvastatin. RESULTS: Kinome analysis can distinguish between non-specific, toxic effects caused by 10 µM of Lovastatin and specific effects on cell signalling caused by 2 µM Lovastatin. Statins induce upregulation of PTEN activity leading to downregulation of the PI3K/Akt/mTOR signalling. Treatment of cells with the specific BMP inhibitor Noggin as well as PTEN knockdown and transfection of cells with a constitutively active form of AKT abolishes the effect of Lovastatin on mTOR phosphorylation. Experiments in xenografts and in patients treated with Simvastatin confirm statin-mediated BMP pathway activation, activation of PTEN and downregulation of mTOR signalling. CONCLUSIONS: Statins induce BMP-specific activation of PTEN and inhibition of PI3K/Akt/mTOR signalling in CRC.
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Neoplasias Colorretais/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fosfotransferases/metabolismo , Proteoma/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Feminino , Células HCT116 , Células HT29 , Humanos , Lovastatina/farmacologia , Camundongos , Camundongos Nus , Fosfoproteínas/efeitos dos fármacos , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Fosfotransferases/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteoma/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
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.
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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 RNARESUMO
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.
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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 , HumanosRESUMO
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.
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Carcinogênese/genética , Transformação Celular Neoplásica/genética , Microbioma Gastrointestinal/genética , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/microbiologia , Neoplasias Gastrointestinais/patologia , HumanosRESUMO
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.
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The development of resistance against chemotherapy remains one of the major challenges in the clinical management of leukemia. There is still limited insight into the molecular mechanisms that maintain the chemotherapy-resistant phenotype, despite the obvious clinical relevance that such knowledge would have. In this study, we show that the chemotherapy-resistant phenotype of myeloid leukemia cells correlates with activation of the Hedgehog (Hh) pathway, whereas in chemosensitive cells, such activation is less pronounced. Importantly, the overexpression of Hh pathway components induces chemoprotection and inhibition of the pathway reverts chemoresistance of Lucena-1 cells, apparently by interfering with P-glycoprotein-dependent drug resistance. Our data thus identify the Hh pathway as an essential component of multidrug resistance (MDR) myeloid leukemia and suggest that targeting the Hh pathway might be an interesting therapeutic avenue for overcoming MDR resistance in myeloid leukemia.
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Proteínas Hedgehog/fisiologia , Leucemia Mieloide/tratamento farmacológico , Transdução de Sinais/fisiologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , HumanosRESUMO
Natural-food-based compounds show substantial promise for prevention and biotherapy of cancers including leukemia. In general, their mechanism of action remains unclear, hampering rational use of these compounds. Herein we show that the common dietary flavonoid apigenin has anticancer activity, but also may decrease chemotherapy sensitivity, depending on the cell type. We analyzed the molecular consequences of apigenin treatment in two types of leukemia, the myeloid and erythroid subtypes. Apigenin blocked proliferation in both lineages through cell-cycle arrest in G(2)/M phase for myeloid HL60 and G(0)/G(1) phase for erythroid TF1 cells. In both cell lines the JAK/STAT pathway was one of major targets of apigenin. Apigenin inhibited PI3K/PKB pathway in HL60 and induced caspase-dependent apoptosis. In contrast, no apoptosis was detected in TF1 cells, but initiation of autophagy was observed. The block in cell cycle and induction of autophagy observed in this erythroleukemia cell line resulted in a reduced susceptibility toward the commonly used therapeutic agent vincristine. Thus, this study shows that although apigenin is a potential chemopreventive agent due to the induction of leukemia cell-cycle arrest, caution in dietary intake of apigenin should be taken during disease as it potentially interferes with cancer treatment.
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Antineoplásicos/toxicidade , Apigenina/toxicidade , Leucemia/tratamento farmacológico , Antineoplásicos/uso terapêutico , Apigenina/uso terapêutico , Apoptose , Autofagia , Divisão Celular , Linhagem Celular Tumoral , Fase G2 , Humanos , Janus Quinases/metabolismo , Leucemia/prevenção & controle , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Vincristina/uso terapêuticoRESUMO
Pathogenesis of multiple myeloma is associated with an aberrant expression of pro-proliferative, pro-angiogenic and bone-metabolism-modifying factors by malignant plasma cells. Given the frequently long time span from diagnosis of early-stage plasma cell dyscrasias to overt myeloma and the mostly low proliferation rate of malignant plasma cells, we hypothesize these to similarly express a novel class of inhibitory factors of potential prognostic relevance. Bone morphogenic proteins (BMPs) represent possible candidates as they inhibit proliferation, stimulate bone formation and have an effect on the survival of cancer patients. We assessed the expression of BMPs and their receptors by Affymetrix DNA microarrays (n=779) including CD138-purified primary myeloma cell samples (n=635) of previously untreated patients. BMP6 is the only BMP expressed by malignant and normal plasma cells. Its expression is significantly lower in proliferating myeloma cells, myeloma cell lines or plasmablasts. BMP6 significantly inhibits the proliferation of myeloma cell lines, survival of primary myeloma cells and in vitro angiogenesis. A high BMP6 expression in primary myeloma cell samples delineates significantly superior overall survival for patients undergoing high-dose chemotherapy independent of conventional prognostic factors (International Staging System (ISS) stage, beta(2) microglobulin).