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1.
Environ Int ; 186: 108587, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38579450

RESUMEN

Air pollution is a key global environmental problem raising human health concern. It is essential to comprehensively assess the long-term characteristics of air pollution and the resultant health impacts. We first assessed the global trends of fine particulate matter (PM2.5) during 1980-2020 using a monthly global PM2.5 reanalysis dataset, and evaluated their association with three types of climate variability including El Niño-Southern Oscillation, Indian Ocean Dipole and North Atlantic Oscillation. We then estimated PM2.5-attributable premature deaths using integrated exposure-response functions. Results show a significant increasing trend of ambient PM2.5 during 1980-2020 due to increases in anthropogenic emissions. Ambient PM2.5 caused a total of âˆ¼ 135 million premature deaths globally during the four decades. Occurrence of air pollution episodes was strongly associated with climate variability, which were associated with up to 14 % increase in annual global PM2.5-attributable premature deaths.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Salud Global , Material Particulado , Material Particulado/análisis , Contaminación del Aire/estadística & datos numéricos , Humanos , Contaminantes Atmosféricos/análisis , Cambio Climático , Exposición a Riesgos Ambientales/estadística & datos numéricos , Clima , Mortalidad Prematura
2.
Gut Microbes ; 15(1): 2172670, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36852457

RESUMEN

Food additives have been linked to the pro-inflammatory microbial dysbiosis associated with Crohn's disease (CD) but the underlying ecological dynamics are unknown. Here, we examine how selection of food additives affects the growth of multiple strains of a key beneficial bacterium (Faecalibacterium prausnitzii), axenic clinical isolates of proinflammatory bacteria from CD patients (Proteus, Morganella, and Klebsiella spp.), and the consortia of mucosa-associated microbiota recovered from multiple Crohn's disease patients. Bacterial growth of the axenic isolates was evaluated using a habitat-simulating medium supplemented with either sodium sulfite, aluminum silicate, carrageenan, carboxymethylcellulose, polysorbate 80, saccharin, sucralose, or aspartame, intended to approximate concentrations found in food. The microbial consortia recovered from post-operative CD patient mucosal biopsy samples were challenged with either carboxymethylcellulose and/or polysorbate 80, and the bacterial communities compared to unchallenged consortia by 16S rRNA gene amplicon profiling. Growth of all F. prausnitzii strains was arrested when either sodium sulfite or polysorbate 80 was added to cultures at baseline or mid-exponential phase of growth, and the inhibitory effects on the Gram-negative bacteria by sodium sulfite were conditional on oxygen availability. The effects from polysorbate 80, saccharin, carrageenan, and/or carboxymethylcellulose on these bacteria were strain-specific. In addition to their direct effects on bacterial growth, polysorbate 80 and/or carboxymethylcellulose can drive profound changes in the CD mucosa-associated microbiota via niche expansion of Proteus and/or Veillonellaceae - both implicated in early Crohn's disease recurrence. These studies on the interaction of food additives with the enteric microbiota provide a basis for dietary management in Crohn's disease.


Asunto(s)
Enfermedad de Crohn , Microbioma Gastrointestinal , Microbiota , Humanos , Aditivos Alimentarios , Carragenina , Carboximetilcelulosa de Sodio , Polisorbatos/farmacología , ARN Ribosómico 16S/genética , Sacarina , Bacterias/genética
3.
ISME J ; 15(11): 3326-3338, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34035441

RESUMEN

The mucosa-associated microbiota is widely recognized as a potential trigger for Crohn's disease pathophysiology but remains largely uncharacterised beyond its taxonomic composition. Unlike stool microbiota, the functional characterisation of these communities using current DNA/RNA sequencing approaches remains constrained by the relatively small microbial density on tissue, and the overwhelming amount of human DNA recovered during sample preparation. Here, we have used a novel ex vivo approach that combines microbe culture from anaerobically preserved tissue with metagenome sequencing (MC-MGS) to reveal patient-specific and strain-level differences among these communities in post-operative Crohn's disease patients. The 16 S rRNA gene amplicon profiles showed these cultures provide a representative and holistic representation of the mucosa-associated microbiota, and MC-MGS produced both high quality metagenome-assembled genomes of recovered novel bacterial lineages. The MC-MGS approach also produced a strain-level resolution of key Enterobacteriacea and their associated virulence factors and revealed that urease activity underpins a key and diverse metabolic guild in these communities, which was confirmed by culture-based studies with axenic cultures. Collectively, these findings using MC-MGS show that the Crohn's disease mucosa-associated microbiota possesses taxonomic and functional attributes that are highly individualistic, borne at least in part by novel bacterial lineages not readily isolated or characterised from stool samples using current sequencing approaches.


Asunto(s)
Enfermedad de Crohn , Microbiota , Humanos , Metagenoma , Metagenómica , Membrana Mucosa
4.
Hong Kong Med J ; 25(3): 178-182, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31178437

RESUMEN

INTRODUCTION: Clostridioides difficile infection (CDI) is a leading cause of healthcare-associated infection globally, causing significant morbidity and mortality. Faecal microbiota transplantation (FMT) has emerged as a promising option for recurrent and refractory CDI. This study aimed to assess the safety, efficacy, and feasibility of FMT for CDI in Hong Kong. METHODS: We conducted a single-centre, retrospective study for all consecutive cases of recurrent or refractory CDI who underwent FMT from 2013 to 2018. Clinical demographics, outcome, and safety parameters were collected. RESULTS: A total of 24 patients with recurrent or refractory CDI (median age 70 years, interquartile range=45.0-78.3 years; 67% male) were included. Over 80% had been recently hospitalised or were long-term care facility residents. Faecal microbiota transplantation was delivered by feeding tube in 11 (45.8%), oesophagogastroduodenoscopy in eight (33.3%), and colonoscopy in six (25%) of the patients. Resolution of diarrhoea without relapse within 8 weeks was achieved in 21 out of 24 patients (87.5%) after FMT. No deaths occurred within 30 days. The FMT was well tolerated and no serious adverse events attributable to FMT were reported. CONCLUSION: Our results confirm that FMT is a safe, efficacious, and feasible intervention for patients with refractory or recurrent CDI in Hong Kong. Given the increasing disease burden and the lack of effective alternatives in Hong Kong for difficult-to-treat cases of CDI, we recommend that a territory-wide FMT service be established to address increasing demand for this treatment.


Asunto(s)
Infecciones por Clostridium/terapia , Diarrea/terapia , Trasplante de Microbiota Fecal , Anciano , Colonoscopía , Endoscopía del Sistema Digestivo , Heces/microbiología , Femenino , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento
5.
Ann Oncol ; 29(11): 2254-2260, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30204835

RESUMEN

Background: Cancer-related genes are under intense evolutionary pressure. We conjectured that gene size is an important determinant of amplification propensity for oncogenes and thus cancer susceptibility and therefore could be subject to natural selection. Patients and methods: Gene information, including size and genomic locations, of all protein-coding genes were downloaded from Ensembl (release 87). Quantification of gene amplification was based on Genomic Identification of Significant Targets in Cancer scores obtained from available The Cancer Genome Atlas studies. Results: Oncogenes are larger in size as compared with non-cancer genes (mean size: 92.1 kb versus 61.4 kb; P < 0.0001) in the human genome, which is contributed by both increased total exon size (mean size: 4.6 kb versus 3.4 kb; P < 0.0001) and higher intronic content (mean %: 84.8 versus 78.0; P < 0.01). Such non-random size distribution and intronic composition are conserved in mouse and Drosophila (all P < 0.0001). Stratification by gene age indicated that young oncogenes have been subject to a stronger evolutionary pressure for gene expansion than their non-cancer counterparts. Pan-cancer analysis demonstrated that larger oncogenes were amplified to a lesser extent. Tumor-suppressor genes also moved toward small oncogenes in the course of evolution. Conclusions: Oncogenes expand in size whereas tumor-suppressor genes move closer to small oncogenes in the course of evolution to withstand oncogenic somatic amplification. Our findings have shed new light on the previously unappreciated influence of gene size on oncogene amplification and elucidated how cancers have shaped our genome to its present configuration.


Asunto(s)
Evolución Molecular , Regulación Neoplásica de la Expresión Génica , Genoma Humano/genética , Neoplasias/genética , Oncogenes/genética , Animales , Biología Computacional , Conjuntos de Datos como Asunto , Drosophila , Amplificación de Genes , Genes Supresores de Tumor , Genómica/métodos , Humanos , Ratones
6.
Aliment Pharmacol Ther ; 47(9): 1306-1316, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29520872

RESUMEN

BACKGROUND: In the large randomised NEPTUNE study, peginterferon alfa-2a 180 µg/wk for 48 weeks produced higher hepatitis B e antigen (HBeAg) seroconversion rates 24 weeks post-treatment (36%) than a lower dose (90 µg/wk) and/or shorter duration (24 weeks) (range 14%-26%). AIM: To determine seroconversion rates 5 years after completion of treatment in NEPTUNE. METHODS: HBeAg-positive patients who completed 24 weeks' follow-up in NEPTUNE (with peginterferon alfa-2a 90 µg/wk × 24 weeks [group 1]; 180 µg/wk × 24 weeks [2]; 90 µg/wk × 48 weeks [3] or 180 µg/wk × 48 weeks [4]) were followed up. RESULTS: Three hundred and eighty three of the 544 patients in the original study were enrolled in the long-term follow-up study. Many patients (196 overall; more in groups 1-3 than 4) received nucleos(t)ide analogues or immunomodulators during follow-up, and more patients had missing data at year 5 in groups 2 and 4 (48 weeks, 50/112) than in groups 1 and 3 (24 weeks, 23/103), which confounds the planned per-protocol analysis. HBeAg seroconversion rates in groups 1, 2, 3 and 4 at year 5 were 47.5%, 50.7%, 52.2% and 67.1%, respectively, (odds ratio for group 4 versus 1-3: 2.02; 95% CI 1.21, 3.38), using multiple imputation methods for missing measurements. CONCLUSION: Seroconversion rates are durable for up to 5 years after completion of peginterferon alfa-2a therapy and, consistent with NEPTUNE, the results suggest that the licensed regimen (180 µg × 48 weeks) is more efficacious for HBeAg-positive patients than a lower dose and/or shorter treatment duration.


Asunto(s)
Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Respuesta Virológica Sostenida , Adulto , Antivirales/uso terapéutico , ADN Viral/análisis , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Antígenos e de la Hepatitis B/genética , Antígenos e de la Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
7.
Oncogene ; 36(2): 182-193, 2017 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-27212034

RESUMEN

REC8 meiotic recombination protein (REC8) was found to be preferentially methylated in gastric cancer (GC) using promoter methylation array. We aimed to elucidate the epigenetic alteration and biological function of REC8 in GC. REC8 was downregulated in 100% (3/3) of Epstein-Barr virus (EBV)-positive and 80% (8/10) of EBV-negative GC cell lines by promoter methylation, but the expression could be restored through demethylation treatment. Protein expression of REC8 was significantly lower in human primary gastric tumors than in adjacent non-tumor tissues. A negative correlation between methylation and mRNA expression of REC8 was observed in 223 gastric samples of The Cancer Genome Atlas study (r=-0.7018, P<0.001). The methylation level (%) of the REC8 promoter was significantly higher in EBV-positive gastric tumors than in EBV-negative gastric tumors, as shown by bisulfite genomic sequencing (77.6 (69.3-80.5) vs 51.4 (39.5-62.3), median (interquartile range); P<0.001); methylation levels in both subtypes of tumors were significantly higher than in normal stomach tissues (14.8 (4.2-24.0)) (both P<0.001). Multivariate analysis revealed that REC8 methylation was an independent factor for poor survival in GC patients (hazard ratio=1.68, P<0.05). REC8 expression significantly suppressed cell viability, clonogenicity and cell cycle progression; it induced apoptosis and inhibited migration of AGS-EBV (EBV-positive) and BGC823 (EBV-negative) GC cells, and it suppressed tumorigenicity in nude mice. In contrast, knockdown of REC8 in gastric epithelial immortalized GES-1 cells significantly increased cell viability, clonogenicity and migration ability. The tumor-suppressive effect of REC8 is mediated at least in part by the downregulation of genes involved in cell growth (G6PD, SLC2A1, NOL3, MCM2, SNAI1 and SNAI2), and the upregulation of apoptosis/migration inhibitors (GADD45G and LDHA) and tumor suppressors (PinX1, IGFBP3 and ETS2). In conclusion, REC8 is a novel tumor suppressor that is commonly downregulated by promoter methylation in GC, especially in the EBV-associated subtype. Promoter methylation of REC8 is an independent risk factor for the shortened survival of GC patients.


Asunto(s)
Proteínas de Ciclo Celular/genética , Metilación de ADN , Regulación hacia Abajo , Infecciones por Virus de Epstein-Barr/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/virología , Adulto , Anciano , Animales , Línea Celular Tumoral , Movimiento Celular , Epigénesis Genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Trasplante de Neoplasias , Pronóstico , Análisis de Supervivencia
8.
Oncogene ; 35(49): 6271-6280, 2016 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-27132506

RESUMEN

Epidemiological studies showed that obesity and its related non-alcoholic fatty liver disease (NAFLD) promote hepatocellular carcinoma (HCC) development. We aimed to uncover the genetic alterations of NAFLD-HCC using whole-exome sequencing. We compared HCC development in genetically obese mice and dietary obese mice with wild-type lean mice fed a normal chow after treatment with diethylnitrosamine. HCC tumor and adjacent normal samples from obese and lean mice were then subjected to whole-exome sequencing. Functional and mechanistic importance of the identified mutations in Carboxyl ester lipase (Cel) gene and Harvey rat sarcoma virus oncogene 1 (Hras) was further elucidated. We demonstrated significantly higher incidences of HCC in both genetic and dietary obese mice with NAFLD development as compared with lean mice without NAFLD. The mutational signatures of NAFLD-HCC and lean HCC were distinct, with <3% overlapped. Eight metabolic or oncogenic pathways were found to be significantly enriched by mutated genes in NAFLD-HCC, but only two of these pathways were dysregulated by mutations in lean HCC. In particular, Cel was mutated significantly more frequently in NAFLD-HCC than in lean HCC. The multiple-site mutations in Cel are loss-of-function mutations, with effects similar to Cel knock-down. Mutant Cel caused accumulation of cholesteryl ester in liver cells, which led to induction of endoplasmic reticulum stress and consequently activated the IRE1α/c-Jun N-terminal kinase (JNK)/c-Jun/activating protein-1 (AP-1) signaling cascade to promote liver cell growth. In addition, single-site mutations in Hras at codon 61 were found in NAFLD-HCC but none in lean HCC. The gain-of-function mutations in Hras (Q61R and Q61K) significantly promoted liver cell growth through activating the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/3-phosphoinositide-dependent protein kinase-1 (PDK1)/Akt pathways. In conclusion, we have identified mutation signature and pathways in NAFLD-associated HCC. Mutations in Cel and Hras have important roles in NAFLD-associated hepatocellular carcinogenesis.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Obesidad/genética , Animales , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Humanos , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/complicaciones , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Mutación , Obesidad/complicaciones , Obesidad/patología , Transducción de Señal
9.
Aliment Pharmacol Ther ; 43(7): 755-64, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26858128

RESUMEN

BACKGROUND: The performance of faecal occult blood tests (FOBTs) to screen proximally located colorectal cancer (CRC) has produced inconsistent results. AIM: To assess in a meta-analysis, the diagnostic accuracy of FOBTs for relative detection of CRC according to anatomical location of CRC. METHODS: Diagnostic studies including both symptomatic and asymptomatic cohorts assessing performance of FOBTs for CRC were searched from MEDINE and EMBASE. Primary outcome was accuracy of FOBTs according to the anatomical location of CRC. Bivariate random-effects model was used. Subgroup analyses were performed to evaluate test performance of guaiac-based FOBT (gFOBT) and immunochemical-based FOBT (iFOBT). RESULTS: Thirteen studies, with 17 cohorts, reporting performance of FOBT were included; a total of 26 342 patients (mean age 58.9 years; 58.1% male) underwent both colonoscopy and FOBT. Pooled sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of FOBTs for CRC detection in the proximal colon were 71.2% (95% CI 61.3-79.4%), 93.6% (95% CI 90.7-95.7%), 11.1 (95% CI 7.8-15.8) and 0.3 (95% CI 0.2-0.4) respectively. Corresponding findings for CRC detection in distal colon were 80.1% (95% CI 70.9-87.0%), 93.6% (95% CI 90.7-95.7%), 12.6 (95% CI 8.8-18.1) and 0.2 (95% CI 0.1-0.3). The area-under-curve for FOBT detection for proximal and distal CRC were 90% vs. 94% (P = 0.0143). Both gFOBT and iFOBT showed significantly lower sensitivity but comparable specificity for the detection of proximally located CRC compared with distal CRC. CONCLUSION: Faecal occult blood tests, both guaiac- and immunochemical-based, show better diagnostic performance for the relative detection of colorectal cancer in the distal colon than in the proximal bowel.


Asunto(s)
Colon/patología , Colonoscopía/normas , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/normas , Sangre Oculta , Anciano , Estudios de Cohortes , Colonoscopía/métodos , Neoplasias Colorrectales/sangre , Detección Precoz del Cáncer/métodos , Femenino , Guayaco/análisis , Humanos , Masculino , Persona de Mediana Edad
10.
Oncogene ; 35(16): 2133-44, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-26212015

RESUMEN

Accumulating evidence reveals the effectiveness of epigenetic therapy in gastric cancer. However, the molecular mechanisms and targets underlying such therapeutic responses remain elusive. Herein, we report an aberrant yet therapeutically rectifiable epigenetic signaling in gastric carcinogenesis. Administration of DNA-demethylating drug 5-aza-2'-deoxycytidine (5-aza-dC) reduced gastric cancer incidence by ~74% (P < 0.05) in N-nitroso-N-methylurea-treated mice. Through genome-wide methylation scanning, novel promoter hypermethylation-silenced and drug-targeted genes were identified in the resected murine stomach tumors and tissues. We uncovered that growth/differentiation factor 1 (Gdf1), a member of the transforming growth factor-ß superfamily, was silenced by promoter hypermethylation in control tumor-bearing mice, but became reactivated in 5-aza-dC-treated mice (P < 0.05). In parallel, the downregulated SMAD2/3 phosphorylation in gastric cancer was revived by 5-aza-dC in vivo. Such hypermethylation-dependent silencing and 5-aza-dC-mediated reactivation of GDF1-SMAD2/3 activity was conserved in human gastric cancer cells (P < 0.05). Subsequent functional characterization further revealed the antiproliferative activity of GDF1, which was exerted through activation of SMAD2/3/4-mediated signaling, transcriptional controls on p15, p21 and c-Myc cell-cycle regulators and phosphorylation of retinoblastoma protein. Clinically, hypermethylation and loss of GDF1 was significantly associated with reduced phosphorylated-SMAD2/3 and poor survival in stomach cancer patients (P < 0.05). Taken together, we demonstrated a causal relationship between DNA methylation and a tumor-suppressive pathway in gastric cancer. Epigenetic silencing of GDF1 abrogates the growth-inhibitory SMAD signaling and renders proliferation advantage to gastric epithelial cells during carcinogenesis. This study lends support to epigenetic therapy for gastric cancer chemoprevention and identifies a potential biomarker for prognosis.


Asunto(s)
Epigénesis Genética , Silenciador del Gen , Factor 1 de Diferenciación de Crecimiento/genética , Transducción de Señal/genética , Proteínas Smad/metabolismo , Neoplasias Gástricas/patología , Animales , Metilación de ADN , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Regiones Promotoras Genéticas , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
11.
Oncogene ; 35(2): 187-95, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-25823027

RESUMEN

Whole-genome and transcriptome sequencing were used to discover novel gene fusions in a case of colon cancer. A tumor-specific LACTB2-NCOA2 fusion originating from intra-chromosomal rearrangement of chromosome 8 was identified at both DNA and RNA levels. Unlike conventional oncogenic chimeric proteins, the fusion product lacks functional domain from respective genes, indicative of an amorphic rearrangement. This chimeric LACTB2-NCOA2 transcript was detected in 6 out of 99 (6.1%) colorectal cancer (CRC) cases, where NCOA2 was significantly downregulated. Enforced expression of wild-type NCOA2 but not the LACTB2-NCOA2 fusion protein impaired the pro-tumorigenic phenotypes of CRC cells, whereas knockdown of endogenous NCOA2 in normal colonocytes had opposite effects. Mechanistically, NCOA2 inhibited Wnt/ß-catenin signaling through simultaneously upregulating inhibitors and downregulating stimulators of Wnt/ß-catenin pathway. Collectively, our data supports that NCOA2 is a novel negative growth regulatory gene repressing the Wnt/ß-catenin pathway in CRC, where recurrent fusion with LACTB2 contributes to its disruption.


Asunto(s)
Neoplasias Colorrectales/genética , Coactivador 2 del Receptor Nuclear/genética , beta-Lactamasas/genética , Anciano , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Reordenamiento Génico , Genes Supresores de Tumor , Humanos , Masculino , Ratones Endogámicos BALB C , Coactivador 2 del Receptor Nuclear/metabolismo , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Vía de Señalización Wnt/genética , Ensayos Antitumor por Modelo de Xenoinjerto , beta Catenina/metabolismo , beta-Lactamasas/metabolismo
12.
Oncogene ; 35(19): 2453-64, 2016 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-26279301

RESUMEN

The Ras association domain family (RASSF) encodes several members with tumor-suppressive potentials. We aimed to investigate the biological function and clinical implication of RASSF10 in gastric cancer (GC). We found that RASSF10 was silenced in six of seven GC cell lines and in primary GC tissues, but was highly expressed in normal gastric tissues. The silence of RASSAF10 was mediated by promoter methylation as evaluated by bisulfite genomic sequencing. RASSF10 expression could be restored by demethylation treatment. A negative correlation between methylation and mRNA expression of RASSF10 was observed in 223 gastric samples of The Cancer Genome Atlas study (P<0.0001). Re-expression of RASSF10 in GC cell lines (AGS and MKN45) significantly suppressed cell viability, colony formation, migration and invasion, reduced cells in S phase, accumulated cells in G2 phase and induced cell apoptosis in vitro, and inhibited tumorigenicity in nude mice. These were confirmed by decreased expression of proliferation markers (proliferating cell nuclear antigen, p-CDC2 and p-CDC25) and increased apoptotic cascades (cleaved caspases-9, -8, -3 and cleaved poly (ADP-ribose) polymerase). Conversely, RASSF10 knockdown in normal gastric cell line yielded an opposing effect. Co-immunoprecipitation combined with mass spectrometry analyses were performed to reveal the downstream effectors of RASSF10. The result revealed that glutathione S-transferase Pi 1 (GSTP1) was a direct cooperator of RASSF10. The tumor-suppressive effect of RASSF10 was partially mediated by cooperating with GSTP1 to deregulate Jun N-terminal kinase (JNK)/c-Jun/AP-1 pathway. Importantly, RASSF10 methylation was detected in 56.6% (98/173) of primary GCs and is an independent risk factor for poor survival of GC patients (P=0.001). In conclusions, RASSF10 functions as a tumor suppressor by cooperating with GSTP1 to deregulate JNK/c-Jun/AP-1 pathway in GC. Promoter methylation of RASSF10 is associated with poor survival of GC patients.


Asunto(s)
Gutatión-S-Transferasa pi/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Transducción de Señal , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Factor de Transcripción AP-1/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Metilación de ADN , Femenino , Silenciador del Gen , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica , Regiones Promotoras Genéticas/genética , Neoplasias Gástricas/genética , Proteínas Supresoras de Tumor/deficiencia , Proteínas Supresoras de Tumor/genética
15.
Aliment Pharmacol Ther ; 41(1): 108-15, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25339583

RESUMEN

BACKGROUND: Serrated polyps of the colorectum have distinct histological features and malignant potential. AIM: To assess the association between the presence of serrated polyps and synchronous advanced colorectal neoplasia. METHODS: Among 4989 asymptomatic Chinese individuals aged 50-70 years who underwent screening colonoscopy, 281 cases with advanced neoplasia (adenoma ≥1 cm, with tubulovillous/villous histology, with high-grade dysplasia, or invasive adenocarcinoma) were compared with 4708 controls without advanced neoplasia for age, sex, smoking history, body mass index, family history of colorectal cancer and the presence of serrated polyps. Independent predictors of advanced neoplasia were determined by multivariate logistic regression analysis. RESULTS: The prevalence of advanced neoplasia and serrated polyps (excluding small distal hyperplastic polyps) was 5.7% and 5.6%, respectively. 3.7% and 0.4% subjects had proximal and large (≥10 mm) serrated polyps, respectively. Independent predictors of synchronous advanced colorectal neoplasia were the presence of sessile serrated adenomas (OR: 4.52; 95% CI: 2.40-8.49), proximal serrated polyps (OR: 2.23, 95% CI: 1.38-3.60), large serrated polyps (OR: 59.25; 95% CI: 18.85-186.21), hyperplastic polyps (OR: 1.66; 95% CI: 1.03-2.67), three or more serrated polyps (OR: 4.86; 95% CI: 1.24-19.15) and one or more non-advanced tubular adenomas (OR: 3.58, 95% CI: 2.59-4.96). CONCLUSION: Detection of proximal, sessile and/or large serrated polyps at screening colonoscopy is independently associated with an increased risk for synchronous advanced neoplasia.


Asunto(s)
Adenocarcinoma/epidemiología , Adenoma/epidemiología , Pólipos del Colon/epidemiología , Neoplasias Colorrectales/epidemiología , Adenocarcinoma/diagnóstico , Adenoma/diagnóstico , Factores de Edad , Anciano , Índice de Masa Corporal , China , Pólipos del Colon/diagnóstico , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología
16.
Gut ; 64(1): 121-32, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24647008

RESUMEN

OBJECTIVE: Since the publication of the first Asia Pacific Consensus on Colorectal Cancer (CRC) in 2008, there are substantial advancements in the science and experience of implementing CRC screening. The Asia Pacific Working Group aimed to provide an updated set of consensus recommendations. DESIGN: Members from 14 Asian regions gathered to seek consensus using other national and international guidelines, and recent relevant literature published from 2008 to 2013. A modified Delphi process was adopted to develop the statements. RESULTS: Age range for CRC screening is defined as 50-75 years. Advancing age, male, family history of CRC, smoking and obesity are confirmed risk factors for CRC and advanced neoplasia. A risk-stratified scoring system is recommended for selecting high-risk patients for colonoscopy. Quantitative faecal immunochemical test (FIT) instead of guaiac-based faecal occult blood test (gFOBT) is preferred for average-risk subjects. Ancillary methods in colonoscopy, with the exception of chromoendoscopy, have not proven to be superior to high-definition white light endoscopy in identifying adenoma. Quality of colonoscopy should be upheld and quality assurance programme should be in place to audit every aspects of CRC screening. Serrated adenoma is recognised as a risk for interval cancer. There is no consensus on the recruitment of trained endoscopy nurses for CRC screening. CONCLUSIONS: Based on recent data on CRC screening, an updated list of recommendations on CRC screening is prepared. These consensus statements will further enhance the implementation of CRC screening in the Asia Pacific region.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/normas , Anciano , Asia , Humanos , Persona de Mediana Edad
17.
Br J Cancer ; 111(9): 1765-71, 2014 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-25233396

RESUMEN

BACKGROUND: The detection of microRNA (miRNA) dysregulation in stool is a novel approach for the diagnosis of colorectal carcinoma (CRC). The aim of this study is to investigate the use of miR-221 and miR-18a in stool samples as non-invasive biomarkers for CRC diagnosis. METHODS: A miRNA expression array containing 667 miRNAs was performed to identify miRNA dysregulation in CRC tissues. We focused on miR-221 and miR-18a, two significantly upregulated miRNAs which were subsequently verified in 40 pairs of CRC tissues and 595 stool samples (198 CRCs, 199 polyps and 198 normal controls). RESULTS: miR-221 and miR-18a were upregulated in the miRNA expression array. miR-221 and miR-18a levels were also significantly higher in 40 CRC tumours compared with their respective adjacent normal tissues. In stool samples, miR-221 and miR-18a showed a significant increasing trend from normal controls to late stages of CRC (P<0.0001). The levels of stool miR-221 and miR-18a were both significantly higher in subjects with stages I+II (miR-221: P<0.0001, miR-18a: P<0.0001) and stages III+IV of CRC (miR-221: P=0.0004, miR-18a: P<0.0001) compared with normal controls. The AUC of stool miR-221 and miR-18a were 0.73 and 0.67 for CRC patients as compared with normal controls, respectively. No significant differences in stool miR-221 and miR-18a levels were found between patients with proximal and distal CRCs. The use of antibiotics did not influence stool miRNA-221 and miRNA-18a levels. CONCLUSIONS: Stool-based miR-221 can be used as a non-invasive biomarker for the detection of CRC.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Heces/química , MicroARNs/genética , Anciano , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , Curva ROC
18.
Curr Med Chem ; 21(21): 2392-400, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24524763

RESUMEN

Cathelicidin is a host defense peptide with multiple innate immunity-related functions. Recent findings indicate that cathelicidin is frequently dysregulated in human cancers where it plays a paradoxical yet dominant role in the regulation of tumor malignancy. In this review, the regulation of malignant phenotypes by cathelicidin in relation to the activation of its receptors and intracellular signaling is discussed.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Carcinogénesis , Neoplasias/patología , Animales , Humanos , Neoplasias/irrigación sanguínea , Neoplasias/metabolismo , Catelicidinas
19.
Aliment Pharmacol Ther ; 38(7): 721-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23915096

RESUMEN

BACKGROUND: The efficacy of adjuvant use of intravenous proton pump inhibitors (PPIs) after endoscopic therapy has been proved in peptic ulcer bleeding patients, but the efficacy of oral PPIs is uncertain. AIM: To compare the clinical outcomes of oral PPIs vs. intravenous PPIs in patients with peptic ulcer bleeding. METHODS: Prospective randomised controlled trials were systematically searched from OVID databases until June 2012. Trials comparing oral and intravenous PPIs among patients with peptic ulcer bleeding were included. Recurrent bleeding, length of hospitalisation, blood transfusion, requirement of surgery and mortality were measured. The risk of bias, study quality and heterogeneity were also evaluated. RESULTS: Six randomised trials from 2006 to 2011 were included. A total of 615 patients were randomly assigned to receive oral PPIs (n = 302) or intravenous PPIs (n = 313). The mean age was 60 years and 71.1% was male. No significant difference between oral and intravenous PPIs was observed regarding recurrent bleeding (RR: 0.92, 95% CI: 0.56-1.50), mean volume of blood transfused (-0.02 unit, 95% CI: -0.29-0.24 unit), requirement of surgery (RR: 0.82, 95% CI: 0.19-3.61) and all-cause mortality (RR: 0.88, 95% CI: 0.29-2.71). The duration of hospital stay in days was significantly shortened in those using oral PPIs (-0.74 day, 95% CI: -1.10 day to -0.39 day). CONCLUSION: Oral PPIs demonstrate a similar effectiveness to intravenous PPIs among patients with peptic ulcer bleeding, but the results were combined from open-labelled trials with limited sample size. A large double-blind non-inferiority trial is required to better assess the role of oral PPIs.


Asunto(s)
Endoscopía/métodos , Úlcera Péptica Hemorrágica/tratamiento farmacológico , Inhibidores de la Bomba de Protones/administración & dosificación , Administración Intravenosa , Administración Oral , Transfusión Sanguínea , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
20.
Aliment Pharmacol Ther ; 38(8): 854-63, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23981095

RESUMEN

BACKGROUND: Complementary and alternative medicine (CAM), particularly herbal therapy, is widely used by patients with inflammatory bowel disease (IBD) but controlled data are limited. AIM: To systematically review the literature on the efficacy of herbal therapy in the treatment of ulcerative colitis (UC) and Crohn's disease (CD). METHODS: Publications in English and non-English literatures (MEDLINE, EMBASE, EBM Reviews, AMED, Global Health) were searched from 1947 to 2013 for controlled clinical studies of herbal therapy in IBD. Outcome measures included response and remission rates. RESULTS: Twenty-one randomised controlled trials (14 UC; 7 CD) including a total of 1484 subjects (mean age 41, 50% female) were analysed. In UC, aloe vera gel, Triticum aestivum (wheat grass juice), Andrographis paniculata extract (HMPL-004) and topical Xilei-san were superior to placebo in inducing remission or response, and curcumin was superior to placebo in maintaining remission; Boswellia serrata gum resin and Plantago ovata seeds were as effective as mesalazine, whereas Oenothera biennis (evening primrose oil) had similar relapse rates as omega-3 fatty acids in the treatment of UC. In CD, Artemisia absinthium (wormwood) and Tripterygium wilfordii were superior to placebo in inducing remission, and preventing clinical recurrence of post-operative CD respectively. CONCLUSIONS: Randomised controlled trials of herbal therapy for the treatment of IBD show encouraging results but studies remain limited and heterogenous. Larger controlled studies with stricter endpoints and better-defined patient groups are required to obtain more conclusive results on the use of CAM therapies in IBD.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Fitoterapia , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Inducción de Remisión , Prevención Secundaria , Resultado del Tratamiento
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