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1.
Circulation ; 148(6): 459-472, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37435755

RESUMEN

BACKGROUND: Gut microbiota have been implicated in atherosclerotic disease, but their relation with subclinical coronary atherosclerosis is unclear. This study aimed to identify associations between the gut microbiome and computed tomography-based measures of coronary atherosclerosis and to explore relevant clinical correlates. METHODS: We conducted a cross-sectional study of 8973 participants (50 to 65 years of age) without overt atherosclerotic disease from the population-based SCAPIS (Swedish Cardiopulmonary Bioimage Study). Coronary atherosclerosis was measured using coronary artery calcium score and coronary computed tomography angiography. Gut microbiota species abundance and functional potential were assessed with shotgun metagenomics sequencing of fecal samples, and associations with coronary atherosclerosis were evaluated with multivariable regression models adjusted for cardiovascular risk factors. Associated species were evaluated for association with inflammatory markers, metabolites, and corresponding species in saliva. RESULTS: The mean age of the study sample was 57.4 years, and 53.7% were female. Coronary artery calcification was detected in 40.3%, and 5.4% had at least 1 stenosis with >50% occlusion. Sixty-four species were associated with coronary artery calcium score independent of cardiovascular risk factors, with the strongest associations observed for Streptococcus anginosus and Streptococcus oralis subsp oralis (P<1×10-5). Associations were largely similar across coronary computed tomography angiography-based measurements. Out of the 64 species, 19 species, including streptococci and other species commonly found in the oral cavity, were associated with high-sensitivity C-reactive protein plasma concentrations, and 16 with neutrophil counts. Gut microbial species that are commonly found in the oral cavity were negatively associated with plasma indole propionate and positively associated with plasma secondary bile acids and imidazole propionate. Five species, including 3 streptococci, correlated with the same species in saliva and were associated with worse dental health in the Malmö Offspring Dental Study. Microbial functional potential of dissimilatory nitrate reduction, anaerobic fatty acid ß-oxidation, and amino acid degradation were associated with coronary artery calcium score. CONCLUSIONS: This study provides evidence of an association of a gut microbiota composition characterized by increased abundance of Streptococcus spp and other species commonly found in the oral cavity with coronary atherosclerosis and systemic inflammation markers. Further longitudinal and experimental studies are warranted to explore the potential implications of a bacterial component in atherogenesis.


Asunto(s)
Aterosclerosis , Enfermedad de la Arteria Coronaria , Humanos , Femenino , Persona de Mediana Edad , Masculino , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/epidemiología , Estudios Transversales , Calcio , Aterosclerosis/epidemiología , Streptococcus
2.
Brief Bioinform ; 22(6)2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34015811

RESUMEN

Formalin-fixed paraffin-embedded tissue, the most common tissue specimen stored in clinical practice, presents challenges in the analysis due to formalin-induced artifacts. Here, we present Strand Orientation Bias Detector (SOBDetector), a flexible computational platform compatible with all the common somatic SNV-calling pipelines, designed to assess the probability whether a given detected mutation is an artifact. The underlying predictor mechanism is based on the posterior distribution of a Bayesian logistic regression model trained on The Cancer Genome Atlas whole exomes. SOBDetector is a freely available cross-platform program, implemented in Java 1.8.


Asunto(s)
Artefactos , Técnicas Citológicas/normas , Secuenciación de Nucleótidos de Alto Rendimiento/normas , Modelos Estadísticos , Análisis de Secuencia de ADN/normas , Moldes Genéticos , Algoritmos , ADN de Neoplasias , Bases de Datos Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Mutación , Neoplasias/diagnóstico , Neoplasias/genética , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/métodos
3.
Int J Mol Sci ; 24(14)2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37511184

RESUMEN

Cow's milk protein allergy (CMPA) is a prevalent food allergy among infants and young children. We conducted a randomized, multicenter intervention study involving 194 non-breastfed infants with CMPA until 12 months of age (clinical trial registration: NCT03085134). One exploratory objective was to assess the effects of a whey-based extensively hydrolyzed formula (EHF) supplemented with 2'-fucosyllactose (2'-FL) and lacto-N-neotetraose (LNnT) on the fecal microbiome and metabolome in this population. Thus, fecal samples were collected at baseline, 1 and 3 months from enrollment, as well as at 12 months of age. Human milk oligosaccharides (HMO) supplementation led to the enrichment of bifidobacteria in the gut microbiome and delayed the shift of the microbiome composition toward an adult-like pattern. We identified specific HMO-mediated changes in fecal amino acid degradation and bile acid conjugation, particularly in infants commencing the HMO-supplemented formula before the age of three months. Thus, HMO supplementation partially corrected the dysbiosis commonly observed in infants with CMPA. Further investigation is necessary to determine the clinical significance of these findings in terms of a reduced incidence of respiratory infections and other potential health benefits.


Asunto(s)
Microbioma Gastrointestinal , Hipersensibilidad a la Leche , Niño , Femenino , Animales , Bovinos , Humanos , Lactante , Preescolar , Leche Humana , Oligosacáridos , Suplementos Dietéticos , Metaboloma , Fórmulas Infantiles/química
4.
Gastroenterology ; 157(3): 637-646.e4, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31095949

RESUMEN

BACKGROUND & AIMS: Enteropathy and small-intestinal ulcers are common adverse effects of nonsteroidal anti-inflammatory drugs such as acetylsalicylic acid (ASA). Safe, cytoprotective strategies are needed to reduce this risk. Specific bifidobacteria might have cytoprotective activities, but little is known about these effects in humans. We used serial video capsule endoscopy (VCE) to assess the efficacy of a specific Bifidobacterium strain in healthy volunteers exposed to ASA. METHODS: We performed a single-site, double-blind, parallel-group, proof-of-concept analysis of 75 heathy volunteers given ASA (300 mg) daily for 6 weeks, from July 31 through October 24, 2017. The participants were randomly assigned (1:1) to groups given oral capsules of Bifidobacterium breve (Bif195) (≥5 × 1010 colony-forming units) or placebo daily for 8 weeks. Small-intestinal damage was analyzed by serial VCE at 6 visits. The area under the curve (AUC) for intestinal damage (Lewis score) and the AUC value for ulcers were the primary and first-ranked secondary end points of the trial, respectively. RESULTS: Efficacy data were obtained from 35 participants given Bif195 and 31 given placebo. The AUC for Lewis score was significantly lower in the Bif195 group (3040 ± 1340 arbitrary units) than the placebo group (4351 ± 3195) (P = .0376). The AUC for ulcer number was significantly lower in the Bif195 group (50.4 ± 53.1 arbitrary units) than in the placebo group (75.2 ± 85.3 arbitrary units) (P = .0258). Twelve adverse events were reported from the Bif195 group and 20 from the placebo group. None of the events was determined to be related to Bif195 intake. CONCLUSIONS: In a randomized, double-blind trial of healthy volunteers, we found oral Bif195 to safely reduce the risk of small-intestinal enteropathy caused by ASA. ClinicalTrials.gov no: NCT03228589.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/efectos adversos , Bifidobacterium breve/crecimiento & desarrollo , Microbioma Gastrointestinal , Intestino Delgado/efectos de los fármacos , Intestino Delgado/microbiología , Probióticos/administración & dosificación , Úlcera/prevención & control , Adolescente , Adulto , Endoscopía Capsular , Método Doble Ciego , Femenino , Voluntarios Sanos , Humanos , Intestino Delgado/patología , Irlanda , Masculino , Probióticos/efectos adversos , Factores de Tiempo , Úlcera/inducido químicamente , Úlcera/microbiología , Úlcera/patología , Adulto Joven
5.
N Engl J Med ; 366(10): 883-892, 2012 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-22397650

RESUMEN

BACKGROUND: Intratumor heterogeneity may foster tumor evolution and adaptation and hinder personalized-medicine strategies that depend on results from single tumor-biopsy samples. METHODS: To examine intratumor heterogeneity, we performed exome sequencing, chromosome aberration analysis, and ploidy profiling on multiple spatially separated samples obtained from primary renal carcinomas and associated metastatic sites. We characterized the consequences of intratumor heterogeneity using immunohistochemical analysis, mutation functional analysis, and profiling of messenger RNA expression. RESULTS: Phylogenetic reconstruction revealed branched evolutionary tumor growth, with 63 to 69% of all somatic mutations not detectable across every tumor region. Intratumor heterogeneity was observed for a mutation within an autoinhibitory domain of the mammalian target of rapamycin (mTOR) kinase, correlating with S6 and 4EBP phosphorylation in vivo and constitutive activation of mTOR kinase activity in vitro. Mutational intratumor heterogeneity was seen for multiple tumor-suppressor genes converging on loss of function; SETD2, PTEN, and KDM5C underwent multiple distinct and spatially separated inactivating mutations within a single tumor, suggesting convergent phenotypic evolution. Gene-expression signatures of good and poor prognosis were detected in different regions of the same tumor. Allelic composition and ploidy profiling analysis revealed extensive intratumor heterogeneity, with 26 of 30 tumor samples from four tumors harboring divergent allelic-imbalance profiles and with ploidy heterogeneity in two of four tumors. CONCLUSIONS: Intratumor heterogeneity can lead to underestimation of the tumor genomics landscape portrayed from single tumor-biopsy samples and may present major challenges to personalized-medicine and biomarker development. Intratumor heterogeneity, associated with heterogeneous protein function, may foster tumor adaptation and therapeutic failure through Darwinian selection. (Funded by the Medical Research Council and others.).


Asunto(s)
Carcinoma de Células Renales/genética , Evolución Molecular , Heterogeneidad Genética , Neoplasias Renales/genética , Fenotipo , Biomarcadores de Tumor , Biopsia , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/secundario , Aberraciones Cromosómicas , Everolimus , Exoma , Heterogeneidad Genética/efectos de los fármacos , Humanos , Inmunosupresores/farmacología , Riñón/patología , Neoplasias Renales/patología , Mutación , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/patología , Filogenia , Ploidias , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Sirolimus/análogos & derivados , Sirolimus/farmacología
6.
Nat Genet ; 38(9): 1043-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16921376

RESUMEN

We developed a computational method to characterize aneuploidy in tumor samples based on coordinated aberrations in expression of genes localized to each chromosomal region. We summarized the total level of chromosomal aberration in a given tumor in a univariate measure termed total functional aneuploidy. We identified a signature of chromosomal instability from specific genes whose expression was consistently correlated with total functional aneuploidy in several cancer types. Net overexpression of this signature was predictive of poor clinical outcome in 12 cancer data sets representing six cancer types. Also, the signature of chromosomal instability was higher in metastasis samples than in primary tumors and was able to stratify grade 1 and grade 2 breast tumors according to clinical outcome. These results provide a means to assess the potential role of chromosomal instability in determining malignant potential over a broad range of tumors.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Inestabilidad Cromosómica , Perfilación de la Expresión Génica , Neoplasias/diagnóstico , Aneuploidia , Neoplasias de la Mama/patología , Estudios de Cohortes , Femenino , Humanos , Metástasis de la Neoplasia , Neoplasias/genética , Neoplasias/patología , Pronóstico
7.
Magy Seb ; 66(6): 331-7, 2013 Dec.
Artículo en Húngaro | MEDLINE | ID: mdl-24333978

RESUMEN

UNLABELLED: INTRODUCTION/AIM OF THE STUDY: Preoperative thrombocytosis proved to be a negative prognostic factor in several solid tumor. However, there is still debate in the literature regarding colorectal cancer. The aim of our study was to examine whether thrombocytosis is an independent risk factor for metastasis development and predictor of survival in colorectal cancer. MATERIALS AND METHODS: Clinicopathological data of 336 patients with colorectal cancer (CRC) and 118 patients with liver metastasis of colorectal cancer (mCRC) who had operation between 2001 and 2011 were collected retrospectively. Thrombocytosis was defined as 400 G/L < platelet count. Disease-free survival (DFS) and overall survival (OS) were determined with Kaplan-Meier method supported by log-rank test. RESULTS: Both in the CRC and the mCRC group OS was significantly shorter in patients who had elevated platelet count (HR = 2.2, p < 0.001 and HR = 2.9, p = 0.018, respectively). Multivariate analysis confirmed that elevated platelet count was an independent prognostic factor of both CRC (HR = 1.7, p = 0.035) and mCRC (HR = 3.1, p = 0.017). DFS was significantly shorter in patients with elevated platelet count in the CRC group (HR = 2.0, p = 0.011). DISCUSSION: The platelet count is a valuable and cheap prognostic marker for the prediction of survival in patients both with CRC and mCRC.


Asunto(s)
Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Trombocitosis/etiología , Anciano , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Recuento de Plaquetas , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Trombocitosis/sangre , Trombocitosis/mortalidad
8.
Bioorg Med Chem ; 20(1): 167-76, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22154557

RESUMEN

The NCI60 database is the largest available collection of compounds with measured anti-cancer activity. The strengths and limitations for using the NCI60 database as a source of new anti-cancer agents are explored and discussed in relation to previous studies. We selected a sub-set of 2333 compounds with reliable experimental half maximum growth inhibitions (GI(50)) values for 30 cell lines from the NCI60 data set and evaluated their growth inhibitory effect (chemosensitivity) with respect to tissue of origin. This was done by identifying natural clusters in the chemosensitivity data set and in a data set of expression profiles of 1901 genes for the corresponding tumor cell lines. Five clusters were identified based on the gene expression data using self-organizing maps (SOM), comprising leukemia, melanoma, ovarian and prostate, basal breast, and luminal breast cancer cells, respectively. The strong difference in gene expression between basal and luminal breast cancer cells was reflected clearly in the chemosensitivity data. Although most compounds in the data set were of low potency, high efficacy compounds that showed specificity with respect to tissue of origin could be found. Furthermore, eight potential topoisomerase II inhibitors were identified using a structural similarity search. Finally, a set of genes with expression profiles that were significantly correlated with anti-cancer drug activity was identified. Our study demonstrates that the combined data sets, which provide comprehensive information on drug activity and gene expression profiles of tumor cell lines studied, are useful for identifying potential new active compounds.


Asunto(s)
Antineoplásicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias/patología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Análisis por Conglomerados , Bases de Datos Factuales , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Neoplasias/tratamiento farmacológico
9.
Nucleic Acids Res ; 38(4): e27, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19969549

RESUMEN

DNA microarray measurements are susceptible to error caused by non-specific hybridization between a probe and a target (cross-hybridization), or between two targets (bulk-hybridization). Search algorithms such as BLASTN can quickly identify potentially hybridizing sequences. We set out to improve BLASTN accuracy by modifying the substitution matrix and gap penalties. We generated gene expression microarray data for samples in which 1 or 10% of the target mass was an exogenous spike of known sequence. We found that the 10% spike induced 2-fold intensity changes in 3% of the probes, two-third of which were decreases in intensity likely caused by bulk-hybridization. These changes were correlated with similarity between the spike and probe sequences. Interestingly, even very weak similarities tended to induce a change in probe intensity with the 10% spike. Using this data, we optimized the BLASTN substitution matrix to more accurately identify probes susceptible to non-specific hybridization with the spike. Relative to the default substitution matrix, the optimized matrix features a decreased score for A-T base pairs relative to G-C base pairs, resulting in a 5-15% increase in area under the ROC curve for identifying affected probes. This optimized matrix may be useful in the design of microarray probes, and in other BLASTN-based searches for hybridization partners.


Asunto(s)
Algoritmos , Sondas de ADN/química , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Alineación de Secuencia/métodos , Secuencia de Bases , Levaduras/genética , Levaduras/metabolismo
10.
Proc Natl Acad Sci U S A ; 106(21): 8671-6, 2009 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-19458043

RESUMEN

Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells. Overexpression of these "CIN-survival" genes is associated with poor outcome in estrogen receptor-positive breast cancer and occurs frequently in basal-like and Her2-positive cases. In diploid cells, but not in chromosomally unstable cells, paclitaxel causes repression of CIN-survival genes, followed by cell death. In the OV01 ovarian cancer clinical trial, a high level of CIN was associated with taxane resistance but carboplatin sensitivity, indicating that CIN may determine MTS response in vivo. Thus, pretherapeutic assessment of CIN may optimize treatment stratification and clinical trial design using these agents.


Asunto(s)
Hidrocarburos Aromáticos con Puentes/farmacología , Inestabilidad Cromosómica/efectos de los fármacos , Inestabilidad Cromosómica/genética , Taxoides/farmacología , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Microtúbulos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Paclitaxel/toxicidad , Reacción en Cadena de la Polimerasa , Pronóstico
11.
Front Nutr ; 9: 920362, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35873420

RESUMEN

Background: Human milk oligosaccharides (HMOs) have important biological functions for a healthy development in early life. Objective: This study aimed to investigate gut maturation effects of an infant formula containing five HMOs (2'-fucosyllactose, 2',3-di-fucosyllactose, lacto-N-tetraose, 3'-sialyllactose, and 6'-sialyllactose). Methods: In a multicenter study, healthy infants (7-21 days old) were randomly assigned to a standard cow's milk-based infant formula (control group, CG); the same formula with 1.5 g/L HMOs (test group 1, TG1); or with 2.5 g/L HMOs (test group 2, TG2). A human milk-fed group (HMG) was enrolled as a reference. Fecal samples collected at baseline (n∼150/formula group; HMG n = 60), age 3 (n∼140/formula group; HMG n = 65) and 6 (n∼115/formula group; HMG n = 60) months were analyzed for microbiome (shotgun metagenomics), metabolism, and biomarkers. Results: At both post-baseline visits, weighted UniFrac analysis indicated different microbiota compositions in the two test groups (TGs) compared to CG (P < 0.01) with coordinates closer to that of HMG. The relative abundance of Bifidobacterium longum subsp. infantis (B. infantis) was higher in TGs vs. CG (P < 0.05; except at 6 months: TG2 vs. CG P = 0.083). Bifidobacterium abundance was higher by ∼45% in TGs vs. CG at 6-month approaching HMG. At both post-baseline visits, toxigenic Clostridioides difficile abundance was 75-85% lower in TGs vs. CG (P < 0.05) and comparable with HMG. Fecal pH was significantly lower in TGs vs. CG, and the overall organic acid profile was different in TGs vs. CG, approaching HMG. At 3 months, TGs (vs. CG) had higher secretory immunoglobulin A (sIgA) and lower alpha-1-antitrypsin (P < 0.05). At 6 months, sIgA in TG2 vs. CG remained higher (P < 0.05), and calprotectin was lower in TG1 (P < 0.05) vs. CG. Conclusion: Infant formula with a specific blend of five HMOs supports the development of the intestinal immune system and gut barrier function and shifts the gut microbiome closer to that of breastfed infants with higher bifidobacteria, particularly B. infantis, and lower toxigenic Clostridioides difficile. Clinical Trial Registration: [https://clinicaltrials.gov/ct2/show/], identifier [NCT03722550].

12.
Front Nutr ; 9: 935711, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990340

RESUMEN

Human milk oligosaccharides (HMOs) are structurally diverse oligosaccharides present in breast milk, supporting the development of the gut microbiota and immune system. Previously, 2-HMO (2'fucosyllactose, lacto-N-neotetraose) compared to control formula feeding was associated with reduced risk of lower respiratory tract infections (LRTIs), in part linked to lower acetate and higher bifidobacteria proportions. Here, our objective was to gain further insight into additional molecular pathways linking the 2-HMO formula feeding and LRTI mitigation. From the same trial, we measured the microbiota composition and 743 known biochemical species in infant stool at 3 months of age using shotgun metagenomic sequencing and untargeted mass spectrometry metabolomics. We used multivariate analysis to identify biochemicals associated to 2-HMO formula feeding and LRTI and integrated those findings with the microbiota compositional data. Three molecular pathways stood out: increased gamma-glutamylation and N-acetylation of amino acids and decreased inflammatory signaling lipids. Integration of stool metagenomic data revealed some Bifidobacterium and Bacteroides species to be implicated. These findings deepen our understanding of the infant gut/microbiome co-metabolism in early life and provide evidence for how such metabolic changes may influence immune competence at distant mucosal sites such as the airways.

13.
Nat Commun ; 13(1): 5370, 2022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-36151114

RESUMEN

Human gut microbiota produce a variety of molecules, some of which enter the bloodstream and impact health. Conversely, dietary or pharmacological compounds may affect the microbiota before entering the circulation. Characterization of these interactions is an important step towards understanding the effects of the gut microbiota on health. In this cross-sectional study, we used deep metagenomic sequencing and ultra-high-performance liquid chromatography linked to mass spectrometry for a detailed characterization of the gut microbiota and plasma metabolome, respectively, of 8583 participants invited at age 50 to 64 from the population-based Swedish CArdioPulmonary bioImage Study. Here, we find that the gut microbiota explain up to 58% of the variance of individual plasma metabolites and we present 997 associations between alpha diversity and plasma metabolites and 546,819 associations between specific gut metagenomic species and plasma metabolites in an online atlas ( https://gutsyatlas.serve.scilifelab.se/ ). We exemplify the potential of this resource by presenting novel associations between dietary factors and oral medication with the gut microbiome, and microbial species strongly associated with the uremic toxin p-cresol sulfate. This resource can be used as the basis for targeted studies of perturbation of specific metabolites and for identification of candidate plasma biomarkers of gut microbiota composition.


Asunto(s)
Microbioma Gastrointestinal , Biomarcadores , Estudios Transversales , Microbioma Gastrointestinal/genética , Humanos , Metaboloma , Metabolómica/métodos , Persona de Mediana Edad , Tóxinas Urémicas
14.
BMC Bioinformatics ; 12: 474, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22172014

RESUMEN

BACKGROUND: Interpretation of gene expression microarrays requires a mapping from probe set to gene. On many Affymetrix gene expression microarrays, a given gene may be detected by multiple probe sets, which may deliver inconsistent or even contradictory measurements. Therefore, obtaining an unambiguous expression estimate of a pre-specified gene can be a nontrivial but essential task. RESULTS: We developed scoring methods to assess each probe set for specificity, splice isoform coverage, and robustness against transcript degradation. We used these scores to select a single representative probe set for each gene, thus creating a simple one-to-one mapping between gene and probe set. To test this method, we evaluated concordance between protein measurements and gene expression values, and between sets of genes whose expression is known to be correlated. For both test cases, we identified genes that were nominally detected by multiple probe sets, and we found that the probe set chosen by our method showed stronger concordance. CONCLUSIONS: This method provides a simple, unambiguous mapping to allow assessment of the expression levels of specific genes of interest.


Asunto(s)
Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Neoplasias de la Mama/genética , Exones , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Sensibilidad y Especificidad
15.
BMC Bioinformatics ; 12: 310, 2011 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-21798043

RESUMEN

BACKGROUND: Genome scale expression profiling of human tumor samples is likely to yield improved cancer treatment decisions. However, identification of clinically predictive or prognostic classifiers can be challenging when a large number of genes are measured in a small number of tumors. RESULTS: We describe an unsupervised method to extract robust, consistent metagenes from multiple analogous data sets. We applied this method to expression profiles from five "double negative breast cancer" (DNBC) (not expressing ESR1 or HER2) cohorts and derived four metagenes. We assessed these metagenes in four similar but independent cohorts and found strong associations between three of the metagenes and agent-specific response to neoadjuvant therapy. Furthermore, we applied the method to ovarian and early stage lung cancer, two tumor types that lack reliable predictors of outcome, and found that the metagenes yield predictors of survival for both. CONCLUSIONS: These results suggest that the use of multiple data sets to derive potential biomarkers can filter out data set-specific noise and can increase the efficiency in identifying clinically accurate biomarkers.


Asunto(s)
Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/genética , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma del Pulmón , Neoplasias de la Mama/tratamiento farmacológico , Estudios de Cohortes , Receptor alfa de Estrógeno/metabolismo , Femenino , Perfilación de la Expresión Génica , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Terapia Neoadyuvante , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Pronóstico , Receptor ErbB-2/metabolismo
16.
Proc Natl Acad Sci U S A ; 105(52): 20870-5, 2008 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-19104045

RESUMEN

Heritable diseases are caused by germ-line mutations that, despite tissuewide presence, often lead to tissue-specific pathology. Here, we make a systematic analysis of the link between tissue-specific gene expression and pathological manifestations in many human diseases and cancers. Diseases were systematically mapped to tissues they affect from disease-relevant literature in PubMed to create a disease-tissue covariation matrix of high-confidence associations of >1,000 diseases to 73 tissues. By retrieving >2,000 known disease genes, and generating 1,500 disease-associated protein complexes, we analyzed the differential expression of a gene or complex involved in a particular disease in the tissues affected by the disease, compared with nonaffected tissues. When this analysis is scaled to all diseases in our dataset, there is a significant tendency for disease genes and complexes to be overexpressed in the normal tissues where defects cause pathology. In contrast, cancer genes and complexes were not overexpressed in the tissues from which the tumors emanate. We specifically identified a complex involved in XY sex reversal that is testis-specific and down-regulated in ovaries. We also identified complexes in Parkinson disease, cardiomyopathies, and muscular dystrophy syndromes that are similarly tissue specific. Our method represents a conceptual scaffold for organism-spanning analyses and reveals an extensive list of tissue-specific draft molecular pathways, both known and unexpected, that might be disrupted in disease.


Asunto(s)
Bases de Datos Factuales , Regulación de la Expresión Génica/genética , Enfermedades Genéticas Congénitas/genética , Enfermedades Genéticas Congénitas/patología , Genoma Humano/genética , Proteoma/genética , Trastornos del Desarrollo Sexual , Femenino , Enfermedades Genéticas Congénitas/metabolismo , Mutación de Línea Germinal , Humanos , Masculino , Oncogenes , Especificidad de Órganos/genética , Ovario/metabolismo , Ovario/patología , Proteoma/metabolismo , PubMed , Testículo/metabolismo , Testículo/patología
17.
Proc Natl Acad Sci U S A ; 105(31): 10907-12, 2008 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-18669654

RESUMEN

Increased alpha-synuclein gene (SNCA) dosage due to locus multiplication causes autosomal dominant Parkinson's disease (PD). Variation in SNCA expression may be critical in common, genetically complex PD but the underlying regulatory mechanism is unknown. We show that SNCA and the heme metabolism genes ALAS2, FECH, and BLVRB form a block of tightly correlated gene expression in 113 samples of human blood, where SNCA naturally abounds (validated P = 1.6 x 10(-11), 1.8 x 10(-10), and 6.6 x 10(-5)). Genetic complementation analysis revealed that these four genes are co-induced by the transcription factor GATA-1. GATA-1 specifically occupies a conserved region within SNCA intron-1 and directly induces a 6.9-fold increase in alpha-synuclein. Endogenous GATA-2 is highly expressed in substantia nigra vulnerable to PD, occupies intron-1, and modulates SNCA expression in dopaminergic cells. This critical link between GATA factors and SNCA may enable therapies designed to lower alpha-synuclein production.


Asunto(s)
Factores de Transcripción GATA/metabolismo , Regulación de la Expresión Génica/fisiología , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , 5-Aminolevulinato Sintetasa/metabolismo , Animales , Northern Blotting , Western Blotting , Células Cultivadas , Biología Computacional , Ensayo de Inmunoadsorción Enzimática , Prueba de Complementación Genética , Humanos , Inmunohistoquímica , Ratones , Análisis por Micromatrices , ARN Interferente Pequeño/genética
18.
Lancet Oncol ; 11(4): 358-65, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20189874

RESUMEN

BACKGROUND: Addition of taxanes to preoperative chemotherapy in breast cancer increases the proportion of patients who have a pathological complete response (pCR). However, a substantial proportion of patients do not respond, and the prognosis is particularly poor for patients with oestrogen-receptor (ER)/progesterone-receptor (PR)/human epidermal growth factor receptor 2 (HER2; ERBB2)-negative (triple-negative) disease who do not achieve a pCR. Reliable identification of such patients is the first step in determining who might benefit from alternative treatment regimens in clinical trials. We previously identified genes involved in mitosis or ceramide metabolism that influenced sensitivity to paclitaxel, with an RNA interference (RNAi) screen in three cancer cell lines, including a triple-negative breast-cancer cell line. Here, we assess these genes as a predictor of pCR to paclitaxel combination chemotherapy in triple-negative breast cancer. METHODS: We derived a paclitaxel response metagene based on mitotic and ceramide genes identified by functional genomics studies. We used area under the curve (AUC) analysis and multivariate logistic regression to retrospectively assess the metagene in six cohorts of patients with triple-negative breast cancer treated with neoadjuvant chemotherapy; two cohorts treated with paclitaxel (n=27, 30) and four treated without paclitaxel (n=88, 28, 48, 39). FINDINGS: The metagene was associated with pCR in paclitaxel-treated cohorts (AUC 0.79 [95% CI 0.53-0.93], 0.72 [0.48-0.90]) but not in non-paclitaxel treated cohorts (0.53 [0.31-0.77], 0.59 [0.22-0.82], 0.53 [0.36-0.71], 0.64 [0.43-0.81]). In multivariate logistic regression, the metagene was associated with pCR (OR 19.92, 2.62-151.57; p=0.0039) with paclitaxel-containing chemotherapy. INTERPRETATION: The paclitaxel response metagene shows promise as a paclitaxel-specific predictor of pCR in patients with triple-negative breast cancer. The metagene is suitable for development into a reverse transcription-PCR assay, for which clinically relevant thresholds could be established in randomised clinical trials. These results highlight the potential for functional genomics to accelerate development of drug-specific predictive biomarkers without the need for training clinical trial cohorts. FUNDING: UK Medical Research Council; Cancer Research UK; the National Institute for Health Research (UK); the Danish Council for Independent Research-Medical Sciences (FSS); Breast Cancer Research Foundation (New York); Fondation Luxembourgeoise contre le Cancer; the Fonds National de la Recherche Scientifique; Brussels Region (IRSIB-IP, Life Sciences 2007) and Walloon Region (Biowin-Keymarker); Sally Pearson Breast Cancer Fund; and the European Commission.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Ensayos de Selección de Medicamentos Antitumorales/métodos , Metagenómica/métodos , Paclitaxel/farmacología , Interferencia de ARN , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Área Bajo la Curva , Neoplasias de la Mama/patología , Ceramidas/genética , Ceramidas/metabolismo , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Mitosis/genética , Modelos Genéticos , Análisis Multivariante , Terapia Neoadyuvante , Paclitaxel/administración & dosificación , Valor Predictivo de las Pruebas , Estudios Retrospectivos
19.
mSphere ; 6(6): e0068621, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34756056

RESUMEN

Acute respiratory infections (ARIs) are one of the most common causes of morbidity and mortality in young children. The aim of our study was to examine whether variation in maternal FUT2 (α1,2-fucosyltransferase 2) and FUT3 (α1,3/4-fucosyltransferase 3) genes, which shape fucosylated human milk oligosaccharides (HMOs) in breast milk, are associated with the occurrence of ARIs in breastfed infants as well as the influence of the nasopharyngeal microbiome on ARI risk. Occurrences of ARIs were prospectively recorded in a cohort of 240 breastfed Bangladeshi infants from birth to 2 years. Secretor and Lewis status was established by sequencing of FUT2/3 genes. The nasopharyngeal microbiome was characterized by shotgun metagenomics, complemented by specific detection of respiratory pathogens; 88.6% of mothers and 91% of infants were identified as secretors. Maternal secretor status was associated with reduced ARI incidence among these infants in the period from birth to 6 months (incidence rate ratio [IRR], 0.66; 95% confidence interval [CI], 0.47 to 0.94; P = 0.020), but not at later time periods. The nasopharyngeal microbiome, despite precise characterization to the species level, was not predictive of subsequent ARIs. The observed risk reduction of ARIs among infants of secretor mothers during the predominant breastfeeding period is consistent with the hypothesis that fucosylated oligosaccharides in human milk contribute to protection against respiratory infections. However, we found no evidence that modulation of the nasopharyngeal microbiome influenced ARI risk. IMPORTANCE The observed risk reduction of acute respiratory infections (ARIs) among infants of secretor mothers during the predominant breastfeeding period is consistent with the hypothesis that fucosylated oligosaccharides in human milk contribute to protection against respiratory infections. Respiratory pathogens were only weak modulators of risk, and the nasopharyngeal microbiome did not influence ARI risk, suggesting that the associated protective effects of human milk oligosaccharides (HMOs) are not conveyed via changes in the nasopharyngeal microbiome. Our observations add to the evidence for a role of fucosylated HMOs in protection against respiratory infections in exclusively or predominantly breastfed infants in low-resource settings. There is no indication that the nasopharyngeal microbiome substantially modulates the risk of subsequent mild ARIs. Larger studies are needed to provide mechanistic insights on links between secretor status, HMOs, and risk of respiratory infections.


Asunto(s)
Bacterias/clasificación , Lactancia Materna , Fucosiltransferasas/metabolismo , Microbioma Gastrointestinal , Leche Humana/metabolismo , Bacterias/crecimiento & desarrollo , Bangladesh , Femenino , Humanos , Lactante , Masculino , Madres , Infecciones del Sistema Respiratorio/microbiología , Galactósido 2-alfa-L-Fucosiltransferasa
20.
Breast Cancer Res Treat ; 123(3): 725-31, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20020197

RESUMEN

Validating prognostic or predictive candidate genes in appropriately powered breast cancer cohorts are of utmost interest. Our aim was to develop an online tool to draw survival plots, which can be used to assess the relevance of the expression levels of various genes on the clinical outcome both in untreated and treated breast cancer patients. A background database was established using gene expression data and survival information of 1,809 patients downloaded from GEO (Affymetrix HGU133A and HGU133+2 microarrays). The median relapse free survival is 6.43 years, 968/1,231 patients are estrogen-receptor (ER) positive, and 190/1,369 are lymph-node positive. After quality control and normalization only probes present on both Affymetrix platforms were retained (n = 22,277). In order to analyze the prognostic value of a particular gene, the cohorts are divided into two groups according to the median (or upper/lower quartile) expression of the gene. The two groups can be compared in terms of relapse free survival, overall survival, and distant metastasis free survival. A survival curve is displayed, and the hazard ratio with 95% confidence intervals and logrank P value are calculated and displayed. Additionally, three subgroups of patients can be assessed: systematically untreated patients, endocrine-treated ER positive patients, and patients with a distribution of clinical characteristics representative of those seen in general clinical practice in the US. Web address: www.kmplot.com . We used this integrative data analysis tool to confirm the prognostic power of the proliferation-related genes TOP2A and TOP2B, MKI67, CCND2, CCND3, CCNDE2, as well as CDKN1A, and TK2. We also validated the capability of microarrays to determine estrogen receptor status in 1,231 patients. The tool is highly valuable for the preliminary assessment of biomarkers, especially for research groups with limited bioinformatic resources.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Marcadores Genéticos , Análisis de Secuencia por Matrices de Oligonucleótidos , Sistemas en Línea , Adulto , Anciano , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Gráficos por Computador , Supervivencia sin Enfermedad , Femenino , Humanos , Internet , Estimación de Kaplan-Meier , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Receptores de Estrógenos/análisis , Reproducibilidad de los Resultados , Factores de Tiempo
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