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As a best-characterized epigenetic modification, DNA methylation plays an important role in mammalian development. Uhrf1 is a critical epigenetic regulator that can bind to hemimethylated DNA and recruit DNA methyltransferase 1 to maintain DNA methylation. So far, the role of Uhrf1-mediated DNA methylation in intestinal development is still unknown. In order to investigate the impact of Uhrf1 deletion in intestinal development, we have successfully constructed the epithelial-specific Uhrf1 knockout mouse model. After Uhrf1 ablation, we found the mutant mice exhibited abnormal epithlial structure with less and shorter villi and shrinked crypts compared with wild type mice via hematoxylin-eosin staining. Further analysis showed that Uhrf1 deletion in the intestinal epithelium significantly decreased the cell proliferation and induced cell apoptosis. In addition, Uhrf1 deletion inhibited the normal epithelial differentiation and the expression of intestinal stem cell marker genes. Preliminary mechanism study revealed that loss of Uhrf1 caused global DNA hypomethylation which induced DNA damage in crypt cells. Taken together, our data suggested that DNA methylation mediated by Uhrf1 is vital for the normal intestinal development. Our results enriched the in vivo role of Uhrf1 and laid the foundation for further epigenetic regulatory mechanism exploration.
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Proteínas Potenciadoras de Unión a CCAAT/fisiología , Metilación de ADN , Epigénesis Genética , Intestinos/crecimiento & desarrollo , Ubiquitina-Proteína Ligasas/fisiología , Animales , Proteínas Potenciadoras de Unión a CCAAT/genética , Eliminación de Gen , Ratones , Ratones Noqueados , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
BACKGROUND: Pancreatic cancer (PC) is a highly deadly malignancy with few effective therapies. We aimed to unmask the role that long non-coding RNA small nucleolar RNA host gene 6 (SNHG6) plays in PC cells by targeting far upstream element binding protein 1 (FUBP1) via microRNA-26a-5p (miR-26a-5p). METHODS: SNHG6 expression was predicted by bioinformatics, followed by verification via reverse transcription quantitative polymerase chain reaction. Then, the interactions among SNHG6, miR-26a-5p, and FUBP1 were detected through online software analysis, dual luciferase reporter assay and RNA pull-down. After that, cells were treated with different small interfering RNAs and/or mimic to determine the interactions among SNHG6, miR-26a-5p, and FUBP1 and their roles in PC cells. Finally, the role of SNHG6 in tumor growth in vivo was evaluated by measuring the growth and weight of transplanted tumors in nude mice. A t-test, one-way and two-way analysis of variance were used for data analysis. RESULTS: Compared with that in normal tissues, SNHG6 was highly expressed in PC tissues (1.00â±â0.05 vs. 1.56â±â0.06, tâ=â16.03, Pâ<â0.001). Compared with that in human pancreatic duct epithelial cells (HPDE6-C7), SNHG6 showed the highest expression in PANC-1 cells (1.00â±â0.06 vs. 3.87â±â0.13, tâ=â34.72, Pâ<â0.001) and the lowest expression in human pancreatic cancer cells (MIAPaCa-2) (1.00â±â0.06 vs. 1.41â±â0.07, tâ=â7.70, Pâ=â0.0015). Compared with the levels in the si-negative control group, SNHG6 (0.97â±â0.05 vs. 0.21â±â0.06, tâ=â16.85, Pâ<â0.001), N-cadherin (0.74â±â0.05 vs. 0.41â±â0.04, tâ=â8.93, Pâ<â0.001), Vimentin (0.55â±â0.04 vs. 0.25â±â0.03, tâ=â10.39, Pâ<â0.001), and ß-catenin (0.62â±â0.05 vs. 0.32â±â0.03, tâ=â8.91, Pâ<â0.001) were decreased, while E-cadherin (0.65â±â0.06 vs. 1.36â±â0.07, tâ=â13.34, Pâ<â0.001) was increased after SNHG6 knockdown or miR-26a-5p overexpression, accompanied by inhibited cell proliferation, migration, and invasion. SNHG6 overexpression exerted the opposite effects. SNHG6 upregulated FUBP1 expression by sponging miR-26a-5p. Silencing SNHG6 blocked the growth of PC in vivo. CONCLUSION: Silencing SNHG6 might ameliorate PC through inhibition of FUBP1 by sponging miR-26a-5p, thus providing further supporting evidence for its use in PC treatment.
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Proteínas de Unión al ADN , MicroARNs , Neoplasias Pancreáticas , ARN Largo no Codificante , Proteínas de Unión al ARN , Animales , Proliferación Celular/genética , Humanos , Ratones , Ratones Desnudos , MicroARNs/genética , Neoplasias Pancreáticas/genética , ARN Largo no Codificante/genética , ARN Nucleolar Pequeño , Regulación hacia ArribaRESUMEN
Previous circular RNA (circRNA) microarray analyses have uncovered an abnormal expression of hsa_circ_0070963 in hepatic stellate cells (HSCs). However, the specific role of hsa_circ_0070963 in liver fibrosis remains unknown. Here, we show that hsa_circ_0070963 inhibits liver fibrosis via regulation of miR-223-3p and LEMD3. Moreover, we demonstrated that hsa_circ_0070963 levels were reduced during liver fibrosis while restoring hsa_circ_0070963 levels abolished HSC activation, with a reduction in α-SMA and type I collagen levels both in vitro and in vivo. Furthermore, hsa_circ_0070963 overexpression suppressed both cell proliferation and the cell cycle of HSCs. MiR-223-3p was confirmed as a target of hsa_circ_0070963 and was shown to be involved in the effects of hsa_circ_0070963 on HSC activation. Furthermore, LEMD3 was confirmed as a target of miR-223-3p and was shown to be responsible for the activation of HSCs. The interactions between hsa_circ_0070963, miR-223-3p, and LEMD3 were validated via bioinformatic analysis, luciferase reporter assays, and rescue experiments. Collectively, hsa_circ_0070963 appeared to function as a miR-223-3p sponge that inhibited HSC activation in liver fibrosis via regulation of miR-223-3p and LEMD3. Therefore, hsa_circ_0070963 may serve as a potential therapeutic target for liver fibrosis.
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Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Cirrosis Hepática/etiología , Proteínas de la Membrana/genética , MicroARNs/genética , Línea Celular , Predisposición Genética a la Enfermedad , Células Estrelladas Hepáticas/metabolismo , Humanos , Cirrosis Hepática/patología , Interferencia de ARNRESUMEN
IMPORTANCE: Effective cancer prevention is based on accurate molecular diagnosis and results of genetic family screening, genotype-informed risk assessment, and tailored strategies for early diagnosis. The expanding etiology for hereditary pheochromocytomas and paragangliomas has recently included SDHA, TMEM127, MAX, and SDHAF2 as susceptibility genes. Clinical management guidelines for patients with germline mutations in these 4 newly included genes are lacking. OBJECTIVE: To study the clinical spectra and age-related penetrance of individuals with mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes. DESIGN, SETTING, AND PATIENTS: This study analyzed the prospective, longitudinally followed up European-American-Asian Pheochromocytoma-Paraganglioma Registry for prevalence of SDHA, TMEM127, MAX, and SDHAF2 germline mutation carriers from 1993 to 2016. Genetic predictive testing and clinical investigation by imaging from neck to pelvis was offered to mutation-positive registrants and their relatives to clinically characterize the pheochromocytoma/paraganglioma diseases associated with mutations of the 4 new genes. MAIN OUTCOMES AND MEASURES: Prevalence and spectra of germline mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes were assessed. The clinical features of SDHA, TMEM127, MAX, and SDHAF2 disease were characterized. RESULTS: Of 972 unrelated registrants without mutations in the classic pheochromocytoma- and paraganglioma-associated genes (632 female [65.0%] and 340 male [35.0%]; age range, 8-80; mean [SD] age, 41.0 [13.3] years), 58 (6.0%) carried germline mutations of interest, including 29 SDHA, 20 TMEM127, 8 MAX, and 1 SDHAF2. Fifty-three of 58 patients (91%) had familial, multiple, extra-adrenal, and/or malignant tumors and/or were younger than 40 years. Newly uncovered are 7 of 63 (11%) malignant pheochromocytomas and paragangliomas in SDHA and TMEM127 disease. SDHA disease occurred as early as 8 years of age. Extra-adrenal tumors occurred in 28 mutation carriers (48%) and in 23 of 29 SDHA mutation carriers (79%), particularly with head and neck paraganglioma. MAX disease occurred almost exclusively in the adrenal glands with frequently bilateral tumors. Penetrance in the largest subset, SDHA carriers, was 39% at 40 years of age and is statistically different in index patients (45%) vs mutation-carrying relatives (13%; P < .001). CONCLUSIONS AND RELEVANCE: The SDHA, TMEM127, MAX, and SDHAF2 genes may contribute to hereditary pheochromocytoma and paraganglioma. Genetic testing is recommended in patients at clinically high risk if the classic genes are mutation negative. Gene-specific prevention and/or early detection requires regular, systematic whole-body investigation.
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Neoplasias de las Glándulas Suprarrenales/genética , Predisposición Genética a la Enfermedad , Neoplasias de Cabeza y Cuello/genética , Neoplasias Primarias Secundarias/genética , Paraganglioma Extraadrenal/genética , Feocromocitoma/genética , Adolescente , Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Niño , Análisis Mutacional de ADN , Detección Precoz del Cáncer/métodos , Complejo II de Transporte de Electrones/genética , Femenino , Pruebas Genéticas , Genotipo , Mutación de Línea Germinal , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Proteínas Mitocondriales/genética , Paraganglioma Extraadrenal/diagnóstico por imagen , Penetrancia , Feocromocitoma/diagnóstico por imagen , Estudios Prospectivos , Sistema de Registros , Adulto JovenRESUMEN
BACKGROUND: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. METHODS: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. RESULTS: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. CONCLUSION: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.
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Four new fungal polyketides named koninginins N-Q (1-4), together with four known analogues (5-8), were isolated from the endophytic fungus Trichoderma koningiopsis YIM PH30002 harbored in Panax notoginseng. Their structures were determined on the basis of spectral data interpretation. These compounds were evaluated for their antifungal activity, nitric oxide inhibition, and anticoagulant activity.
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Eight new fungal polyketides named koningiopisins A-H (1-8) and four previously known polyketides (9-12) were isolated from the endophytic fungus Trichoderma koningiopsis YIM PH 30002. Their structures were elucidated using extensive spectral data interpretation, and their antifungal and synergistic activities were also evaluated. Koningiopisin C (3) exhibited in vitro antifungal activity against the phytopathogenic fungus Plectosphaerella cucumerina with an MIC of 16 µg/mL. Although the antifungal activities of single compounds were not obvious, a mixture of six compounds (4-9) exhibited potent synergistic antifungal activity against P. cucumerina with an MIC of 16 µg/mL, and the antifungal activity of the mixture of any two compounds with a 1:1 ratio was better than that observed from the individual compound. The synergistic biological activity of the metabolites in YIM PH 30002 demonstrates the significant ecological function of the endophyte for its host plant, and provides additional insight into the search for and development of agents for biological control.
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Antifúngicos/aislamiento & purificación , Policétidos/aislamiento & purificación , Trichoderma/química , Antifúngicos/química , Antifúngicos/farmacología , Ascomicetos/efectos de los fármacos , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Policétidos/química , Policétidos/farmacologíaRESUMEN
The mammalian target of rapamycin (mTOR) signaling pathway integrates environmental cues to regulate cell growth and survival through various mechanisms. However, how mTORC1 responds to acute inflammatory signals to regulate bowel regeneration is still obscure. In this study, we investigated the role of mTORC1 in acute inflammatory bowel disease. Inhibition of mTORC1 activity by rapamycin treatment or haploinsufficiency of Rheb through genetic modification in mice impaired intestinal cell proliferation and induced cell apoptosis, leading to high mortality in dextran sodium sulfate- and 2,4,6-trinitrobenzene sulfonic acid-induced colitis models. Through bone marrow transplantation, we found that mTORC1 in nonhematopoietic cells played a major role in protecting mice from colitis. Reactivation of mTORC1 activity by amino acids had a positive therapeutic effect in mTORC1-deficient Rheb(+/-) mice. Mechanistically, mTORC1 mediated IL-6-induced Stat3 activation in intestinal epithelial cells to stimulate the expression of downstream targets essential for cell proliferation and tissue regeneration. Therefore, mTORC1 signaling critically protects against inflammatory bowel disease through modulation of inflammation-induced Stat3 activity. As mTORC1 is an important therapeutic target for multiple diseases, our findings will have important implications for the clinical usage of mTORC1 inhibitors in patients with acute inflammatory bowel disease.
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Colitis/inmunología , Proteínas de Unión al GTP Monoméricas/inmunología , Complejos Multiproteicos/antagonistas & inhibidores , Neuropéptidos/inmunología , Factor de Transcripción STAT3/inmunología , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Trasplante de Médula Ósea , Células CACO-2 , Proliferación Celular/efectos de los fármacos , Colitis/inducido químicamente , Colitis/genética , Colitis/mortalidad , Regulación de la Expresión Génica , Haploinsuficiencia , Humanos , Interleucina-6/genética , Interleucina-6/inmunología , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas de Unión al GTP Monoméricas/deficiencia , Proteínas de Unión al GTP Monoméricas/genética , Complejos Multiproteicos/genética , Complejos Multiproteicos/inmunología , Neuropéptidos/deficiencia , Neuropéptidos/genética , Proteína Homóloga de Ras Enriquecida en el Cerebro , Factor de Transcripción STAT3/genética , Transducción de Señal , Dodecil Sulfato de Sodio , Análisis de Supervivencia , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/inmunología , Ácido TrinitrobencenosulfónicoRESUMEN
Hepatocellular carcinoma (HCC) is a disease with a high incidence and mortality rate worldwide. However, the mechanisms underlying its pathogenesis are still elusive. In recent years, studies on functions of Krüppel-like factors (KLFs) in HCC have shed new light on this field. To date, five members (KLF4, KLF6, KLF8, KLF9, and KLF17) in the KLF family have been reported to function in the pathogenesis of HCC in multiple ways, which hold the potential of deepening and widening our understanding in the initiation and progression of HCC. In this review, we focus on the functions, roles, and regulatory networks of these five KLFs in HCC, summarize key pathways, and propose areas for further investigation, with the hope that this review will provide a reliable and concise reference for readers interested in this area.
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Carcinoma Hepatocelular/genética , Factores de Transcripción de Tipo Kruppel/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/genética , Factores de Transcripción/genética , Carcinoma Hepatocelular/patología , Redes Reguladoras de Genes , Humanos , Factor 4 Similar a Kruppel , Factor 6 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismoRESUMEN
Most cancers develop upon the accumulation of genetic alterations that provoke and sustain the transformed phenotype. Several metabolomic approaches now allow for the global assessment of intermediate metabolites, generating profound insights into the metabolic rewiring associated with malignant transformation. The metabolomic profiling of neoplastic lesions growing in mice, irrespective of their origin, can provide invaluable information on the mechanisms underlying oncogenesis, tumor progression, and response to therapy. Moreover, the metabolomic profiling of tumors growing in mice may result in the identification of novel diagnostic or prognostic biomarkers, which is of great clinical significance. Several methods can be applied to the metabolomic profiling of neoplastic lesions in mice, including mass spectrometry-based techniques (e.g., gas chromatography-, capillary electrophoresis-, or liquid chromatography-coupled mass spectrometry) as well as nuclear magnetic resonance. Here, we compare and discuss the advantages and disadvantages of all these techniques to provide a concise and reliable guide for readers interested in this active area of investigation.
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Metabolómica , Neoplasias Experimentales/metabolismo , Animales , Biomarcadores de Tumor/metabolismo , Cromatografía Liquida , Electroforesis Capilar , Análisis de Fourier , Espectrometría de Masas , Ratones , Neoplasias Experimentales/patología , Resonancia Magnética Nuclear BiomolecularRESUMEN
There is still a lack of satisfactory tumor markers for gastric cancer (GasC). This study is aimed at optimizing parameters in CE-MS based on moving reaction boundary (MRB) so as to improve its sensitivity and stability, and at searching for potential tumor markers of GasC in patients' urine samples via MRB-CE-MS. In this study, several parameters of MRB-CE-MS were investigated and optimized in order to gain optimal stability, sensitivity, and specificity, and was afterwards evaluated as valid. Subsequently, urine samples from GasC patients and control subjects were subjected to MRB-CE-MS analysis under optimized conditions, which successfully distinguished GasC patients from controls, as well as early-stage patients from advanced stage patients. Differentiation performance was evaluated by area under the curve, which showed fine differential value between GasC patients and controls, as well as between early and advanced stage patients (area under the curve value 1.0 and 0.847, respectively). In conclusion, this study established a set of feasible and useful methodology in searching potential tumor markers in urine samples from GasC patients. Moreover, several amino acids have been recognized as potential tumor markers that deserve further investigation.
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Biomarcadores de Tumor/orina , Electroforesis Capilar/métodos , Espectrometría de Masas/métodos , Metaboloma/fisiología , Neoplasias Gástricas/orina , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Metabolómica , Persona de Mediana EdadRESUMEN
The Krüppel-like factor (KLF) family of transcription factors regulates diverse biological processes that include proliferation, differentiation, apoptosis, development, and responses to external stress. In the present study, we aim to investigate the roles of KLF2 in hepatic steatosis. Our results showed that mRNA and protein levels of KLF2 were significantly elevated in livers from obese mice. Adenoviruses-mediated overexpression of KLF2 induced accumulation of triglycerides in C57BL/6 mice, whereas KLF2 silencing ameliorates hepatosteatosis in ob/ob mice. At the molecular level, our data established CD36 as a novel transcriptional target of KLF2. KLF2 upregulated CD36 expression through a consensus binding site on its proximal promoter region. Additionally, the steatotic effect of KLF2 was dramatically inhibited in CD36-null mice. Therefore, our study reveals a novel link between KLF2-induced hepatic triglyceride accumulation and the expression of CD36.
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Antígenos CD36/genética , Hígado Graso/metabolismo , Regulación de la Expresión Génica , Factores de Transcripción de Tipo Kruppel/fisiología , Animales , Antígenos CD36/metabolismo , Hígado Graso/genética , Hipertrigliceridemia/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Especificidad de Órganos , Regiones Promotoras GenéticasRESUMEN
BACKGROUND & AIMS: Gastrointestinal polyposis is a common clinical problem, yet there is no consensus on how to best manage patients with moderate-load polyposis. Identifying genetic features of this disorder could improve management and especially surveillance of these patients. We sought to determine the prevalence of hamartomatous polyposis-associated mutations in the susceptibility genes PTEN, BMPR1A, SMAD4, ENG, and STK11 in individuals with ≥5 gastrointestinal polyps, including at least 1 hamartomatous or hyperplastic/serrated polyp. METHODS: We performed a prospective, referral-based study of 603 patients (median age: 51 years; range, 2-89 years) enrolled from June 2006 through January 2012. Genomic DNA was extracted from peripheral lymphocytes and analyzed for specific mutations and large rearrangements in PTEN, BMPR1A, SMAD4, and STK11, as well as mutations in ENG. Recursive partitioning analysis was used to determine cutoffs for continuous variables. The prevalence of mutations was compared using Fisher's exact test. Logistic regression analyses were used to determine univariate and multivariate risk factors. RESULTS: Of 603 patients, 119 (20%) had a personal history of colorectal cancer and most (n = 461 [76%]) had <30 polyps. Seventy-seven patients (13%) were found to have polyposis-associated mutations, including 11 in ENG (1.8%), 13 in PTEN (2.2%), 13 in STK11 (2.2%), 20 in BMPR1A (3.3%), and 21 in SMAD4 (3.5%). Univariate clinical predictors for risk of having these mutations included age at presentation younger than 40 years (19% vs 10%; P = .008), a polyp burden of ≥30 (19% vs 11%; P = .014), and male sex (16% vs 10%; P = .03). Patients who had ≥1 ganglioneuroma (29% vs 2%; P < .001) or presented with polyps of ≥3 histologic types (20% vs 2%; P = .003) were more likely to have germline mutations in PTEN. CONCLUSIONS: Age younger than 40 years, male sex, and specific polyp histologies are significantly associated with risk of germline mutations in hamartomatous-polyposis associated genes. These associations could guide clinical decision making and further investigations.
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Antígenos CD/genética , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Pólipos del Colon/genética , Mutación de Línea Germinal , Fosfohidrolasa PTEN/genética , Proteínas Serina-Treonina Quinasas/genética , Receptores de Superficie Celular/genética , Proteína Smad4/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Endoglina , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Peutz-Jeghers/genética , Estudios Prospectivos , Adulto JovenRESUMEN
Cowden syndrome (CS) is a difficult-to-recognize multiple hamartoma syndrome with high risks of breast, thyroid, and other cancers. Germline mutations in PTEN on 10q23 were found to cause 85% of CS when accrued from tertiary academic centers, but prospective accrual from the community over the last 12 years has revealed a 25% PTEN mutation frequency. PTEN is the phosphatase that has been implicated in a heritable cancer syndrome and subsequently in multiple sporadic cancers and developmental processes. PTEN antagonizes the AKT1/PI3K signaling pathway and has roles in cell cycle, migration, cell polarity, and apoptosis. We report that 8 of 91 (8.8%) unrelated CS individuals without germline PTEN mutations carried 10 germline PIK3CA mutations (7 missense, 1 nonsense, and 2 indels) and 2 (2.2%) AKT1 mutations. These mutations result in significantly increased P-Thr308-AKT and increased cellular PIP3. Our observations suggest that PIK3CA and AKT1 are CS susceptibility genes.
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Síndrome de Hamartoma Múltiple/genética , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Fosfatidilinositol 3-Quinasa Clase I , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Fosfohidrolasa PTENRESUMEN
Aim. The study was to investigate the metabolic profile of urine metabolites and to elucidate their clinical significance in patients with colorectal cancer. Methods. Colorectal cancers from early stage and advanced stage were used in this study. Urine samples of colorectal cancer patients and healthy adults were collected and subjected to capillary electrophoresis mass spectrometry based on moving reaction boundary analysis. The metabolic data were analyzed by SPSS 17.0 to find urinary biomarkers for colorectal cancer. Results. The results indicated that the urine metabolic profiling of colorectal cancer patients had significant changes compared with the normal controls, and there were also differences between early stage and advanced colorectal cancer patients. Compared with the control group, the levels of isoleucine, valine, arginine, lactate acid and leucine increased (P < 0.05), but those of histidine, methionine, serine, aspartic acid, citric acid, succinate, and malic acid decreased in urine samples from colorectal cancer (P < 0.05). Furthermore, the levels of isoleucine and valine were lower in urine of patients with advanced colorectal cancer than those in early stage colorectal cancer (P < 0.05). Conclusion. The technique of capillary electrophoresis mass spectrometry based on MRB could reveal the significant metabolic alterations during progression of colorectal cancer, and the method is feasible and may be useful for the early diagnosis of colorectal cancer.
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Aim. Amino acid metabolism in cancer patients differs from that in healthy people. In the study, we performed urine-free amino acid profile of gastric cancer at different stages and health subjects to explore potential biomarkers for diagnosing or screening gastric cancer. Methods. Forty three urine samples were collected from inpatients and healthy adults who were divided into 4 groups. Healthy adults were in group A (n = 15), early gastric cancer inpatients in group B (n = 7), and advanced gastric cancer inpatients in group C (n = 16); in addition, two healthy adults and three advanced gastric cancer inpatients were in group D (n = 5) to test models. We performed urine amino acids profile of each group by applying ion chromatography (IC) technique and analyzed urine amino acids according to chromatogram of amino acids standard solution. The data we obtained were processed with statistical analysis. A diagnostic model was constructed to discriminate gastric cancer from healthy individuals and another diagnostic model for clinical staging by principal component analysis. Differentiation performance was validated by the area under the curve (AUC) of receiver-operating characteristic (ROC) curves. Results. The urine-free amino acid profile of gastric cancer patients changed to a certain degree compared with that of healthy adults. Compared with healthy adult group, the levels of valine, isoleucine, and leucine increased (P < 0.05), but the levels of histidine and methionine decreased (P < 0.05), and aspartate decreased significantly (P < 0.01). The urine amino acid profile was also different between early and advanced gastric cancer groups. Compared with early gastric cancer, the levels of isoleucine and valine decreased in advanced gastric cancer (P < 0.05). A diagnosis model constructed for gastric cancer with AUC value of 0.936 tested by group D showed that 4 samples could coincide with it. Another diagnosis model for clinical staging with an AUC value of 0.902 tested by 3 advanced gastric cancer inpatients of group D showed that all could coincide with the model. Conclusions. The noticeable differences of urine-free amino acid profiles between gastric cancer patients and healthy adults indicate that such amino acids as valine, isoleucine, leucine, methionine, histidine and aspartate are important metabolites in cell multiplication and gene expression during tumor growth and metastatic process. The study suggests that urine-free amino acid profiling is of potential value for screening or diagnosing gastric cancer.
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Objective. The present study was performed to investigate the effect of N-desulfated heparin on basic fibroblast growth factor (bFGF) expression, tumor angiogenesis and metastasis of gastric carcinoma. Methods. Human gastric cancer SGC-7901 tissues were orthotopically implanted into the stomach of NOD SCID mice. Twenty mice were randomly divided into two groups which received either intravenous injection of 0.9% NaCl solution (normal saline group) or 10 mg/kg N-desulfated heparin (N-desulfated heparin group) twice weekly for three weeks. In vitro, human gastric carcinoma SGC-7901 cells were treated with N-desulfated heparin in different concentration (0.1 mg/mL, 1 mg/mL, N-desulfated heparin group), and treated with medium (control group). Results. In vivo, the tumor metastasis rates were 9/10 in normal saline group and 2/10 in N-desulfated heparin group (P < 0.05). The intratumoral microvessel density was higher in normal saline group than in N-desulfated heparin group (P < 0.05). bFGF expression in gastric tissue was inhibited by N-desulfated heparin (P < 0.05). There was no bleeding in N-desulfated heparin group. In vitro, N-desulfated heparin inhibited significantly bFGF protein and mRNA expression of gastric carcinoma cells (P < 0.05). Conclusions. N-desulfated heparin can inhibit the metastasis of gastric cancer through inhibiting tumor bFGF expression and tumor angiogenesis with no obvious anticoagulant activity.
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AIM: To gain new insights into tumor metabolism and to identify possible biomarkers with potential diagnostic values to predict tumor metastasis. METHODS: Human gastric cancer SGC-7901 cells were implanted into 24 severe combined immune deficiency (SCID) mice, which were randomly divided into metastasis group (n = 8), non-metastasis group (n = 8), and normal group (n = 8). Urinary metabolomic information was obtained by gas chromatography/mass spectrometry (GC/MS). RESULTS: There were significant metabolic differences among the three groups (t test, P < 0.05). Ten selected metabolites were different between normal and cancer groups (non-metastasis and metastasis groups), and seven metabolites were also different between non-metastasis and metastasis groups. Two diagnostic models for gastric cancer and metastasis were constructed respectively by the principal component analysis (PCA). These PCA models were confirmed by corresponding receiver operating characteristic analysis (area under the curve = 1.00). CONCLUSION: The urinary metabolomic profile is different, and the selected metabolites might be instructive to clinical diagnosis or screening metastasis for gastric cancer.
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Biomarcadores de Tumor/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Metabolómica/métodos , Metástasis de la Neoplasia , Neoplasias Gástricas/patología , Neoplasias Gástricas/orina , Animales , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones SCID , Trasplante de Neoplasias , Análisis de Componente Principal , Curva ROC , Distribución AleatoriaRESUMEN
Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome are allelic, defined by germline PTEN mutations, and collectively referred to as PTEN hamartoma tumor syndrome. To date, there are no existing criteria based on large prospective patient cohorts to select patients for PTEN mutation testing. To address these issues, we conducted a multicenter prospective study in which 3042 probands satisfying relaxed CS clinical criteria were accrued. PTEN mutation scanning, including promoter and large deletion analysis, was performed for all subjects. Pathogenic mutations were identified in 290 individuals (9.5%). To evaluate clinical phenotype and PTEN genotype against protein expression, we performed immunoblotting (PTEN, P-AKT1, P-MAPK1/2) for a patient subset (n = 423). In order to obtain an individualized estimation of pretest probability of germline PTEN mutation, we developed an optimized clinical practice model to identify adult and pediatric patients. For adults, a semiquantitative score-the Cleveland Clinic (CC) score-resulted in a well-calibrated estimation of pretest probability of PTEN status. Overall, decreased PTEN protein expression correlated with PTEN mutation status; decreasing PTEN protein expression correlated with increasing CC score (p < 0.001), but not with the National Comprehensive Cancer Network (NCCN) criteria (p = 0.11). For pediatric patients, we identified highly sensitive criteria to guide PTEN mutation testing, with phenotypic features distinct from the adult setting. Our model improved sensitivity and positive predictive value for germline PTEN mutation relative to the NCCN 2010 criteria in both cohorts. We present the first evidence-based clinical practice model to select patients for genetics referral and PTEN mutation testing, further supported biologically by protein correlation.