Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Funct Integr Genomics ; 23(4): 293, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37682415

RESUMEN

Sporadic Alzheimer's disease (AD) is a complex neurological disorder characterized by many risk loci with potential associations with different traits and diseases. AD, characterized by a progressive loss of neuronal functions, manifests with different symptoms such as decline in memory, movement, coordination, and speech. The mechanisms underlying the onset of AD are not always fully understood, but involve a multiplicity of factors. Early diagnosis of AD plays a central role as it can offer the possibility of early treatment, which can slow disease progression. Currently, the methods of diagnosis are cognitive testing, neuroimaging, or cerebrospinal fluid analysis that can be time-consuming, expensive, invasive, and not always accurate. In the present study, we performed a genetic correlation analysis using genome-wide association statistics from a large study of AD and UK Biobank, to examine the association of AD with other human traits and disorders. In addition, since hippocampus, a part of cerebral cortex could play a central role in several traits that are associated with AD; we analyzed the gene expression profiles of hippocampus of AD patients applying 4 different artificial neural network models. We found 65 traits correlated with AD grouped into 9 clusters: medical conditions, fluid intelligence, education, anthropometric measures, employment status, activity, diet, lifestyle, and sexuality. The comparison of different 4 neural network models along with feature selection methods on 5 Alzheimer's gene expression datasets showed that the simple basic neural network model obtains a better performance (66% of accuracy) than other more complex methods with dropout and weight regularization of the network.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/genética , Estudio de Asociación del Genoma Completo , Mapeo Cromosómico , Hipocampo , Redes Neurales de la Computación
2.
Strahlenther Onkol ; 199(4): 412-419, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36326856

RESUMEN

PURPOSE: Total marrow (and lymphoid) irradiation (TMI-TMLI) is limited by the couch travel range of modern linacs, which forces the treatment delivery to be split into two plans with opposite orientations: a head-first supine upper-body plan, and a feet-first supine lower extremities plan. A specific field junction is thus needed to obtain adequate target coverage in the overlap region of the two plans. In this study, an automatic procedure was developed for field junction creation and lower extremities plan optimization. METHODS: Ten patients treated with TMI-TMLI at our institution were selected retrospectively. The planning of the lower extremities was performed automatically. Target volume parameters (CTV_J­V98% > 98%) at the junction region and several dose statistics (D98%, Dmean, and D2%) were compared between automatic and manual plans. The modulation complexity score (MCS) was used to assess plan complexity. RESULTS: The automatic procedure required 60-90 min, depending on the case. All automatic plans achieved clinically acceptable dosimetric results (CTV_J­V98% > 98%), with significant differences found at the junction region, where Dmean and D2% increased on average by 2.4% (p < 0.03) and 3.0% (p < 0.02), respectively. Similar plan complexity was observed (median MCS = 0.12). Since March 2022, the automatic procedure has been introduced in our clinic, reducing the TMI-TMLI simulation-to-delivery schedule by 2 days. CONCLUSION: The developed procedure allowed treatment planning of TMI-TMLI to be streamlined, increasing efficiency and standardization, preventing human errors, while maintaining the dosimetric plan quality and complexity of manual plans. Automated strategies can simplify the future adoption and clinical implementation of TMI-TMLI treatments in new centers.


Asunto(s)
Médula Ósea , Radioterapia de Intensidad Modulada , Humanos , Médula Ósea/efectos de la radiación , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos , Dosificación Radioterapéutica , Órganos en Riesgo/efectos de la radiación , Planificación de la Radioterapia Asistida por Computador/métodos , Extremidad Inferior
3.
J Appl Clin Med Phys ; 24(6): e13931, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37085997

RESUMEN

PURPOSE: To assess the impact of the planner's experience and optimization algorithm on the plan quality and complexity of total marrow and lymphoid irradiation (TMLI) delivered by means of volumetric modulated arc therapy (VMAT) over 2010-2022 at our institute. METHODS: Eighty-two consecutive TMLI plans were considered. Three complexity indices were computed to characterize the plans in terms of leaf gap size, irregularity of beam apertures, and modulation complexity. Dosimetric points of the target volume (D2%) and organs at risk (OAR) (Dmean) were automatically extracted to combine them with plan complexity and obtain a global quality score (GQS). The analysis was stratified based on the different optimization algorithms used over the years, including a knowledge-based (KB) model. Patient-specific quality assurance (QA) using Portal Dosimetry was performed retrospectively, and the gamma agreement index (GAI) was investigated in conjunction with plan complexity. RESULTS: Plan complexity significantly reduced over the years (r = -0.50, p < 0.01). Significant differences in plan complexity and plan dosimetric quality among the different algorithms were observed. Moreover, the KB model allowed to achieve significantly better dosimetric results to the OARs. The plan quality remained similar or even improved during the years and when moving to a newer algorithm, with GQS increasing from 0.019 ± 0.002 to 0.025 ± 0.003 (p < 0.01). The significant correlation between GQS and time (r = 0.33, p = 0.01) indicated that the planner's experience was relevant to improve the plan quality of TMLI plans. Significant correlations between the GAI and the complexity metrics (r = -0.71, p < 0.01) were also found. CONCLUSION: Both the planner's experience and algorithm version are crucial to achieve an optimal plan quality in TMLI plans. Thus, the impact of the optimization algorithm should be carefully evaluated when a new algorithm is introduced and in system upgrades. Knowledge-based strategies can be useful to increase standardization and improve plan quality of TMLI treatments.


Asunto(s)
Médula Ósea , Radioterapia de Intensidad Modulada , Humanos , Médula Ósea/efectos de la radiación , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos , Irradiación Linfática , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Órganos en Riesgo/efectos de la radiación
4.
Radiol Med ; 128(3): 340-346, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36786971

RESUMEN

PURPOSE: To investigate whether artificial intelligence (AI) can differentiate septic from non-septic total hip arthroplasty (THA) failure based on preoperative MRI features. MATERIALS AND METHODS: We included 173 patients (98 females, age: 67 ± 12 years) subjected to first-time THA revision surgery after preoperative pelvis MRI. We divided the patients into a training/validation/internal testing cohort (n = 117) and a temporally independent external-testing cohort (n = 56). MRI features were used to train, validate and test a machine learning algorithm based on support vector machine (SVM) to predict THA infection on the training-internal validation cohort with a nested fivefold validation approach. Machine learning performance was evaluated on independent data from the external-testing cohort. RESULTS: MRI features were significantly more frequently observed in THA infection (P < 0.001), except bone destruction, periarticular soft-tissue mass, and fibrous membrane (P > 0.005). Considering all MRI features in the training/validation/internal-testing cohort, SVM classifier reached 92% sensitivity, 62% specificity, 79% PPV, 83% NPV, 82% accuracy, and 81% AUC in predicting THA infection, with bone edema, extracapsular edema, and synovitis having been the best predictors. After being tested on the external-testing cohort, the classifier showed 92% sensitivity, 79% specificity, 89% PPV, 83% NPV, 88% accuracy, and 89% AUC in predicting THA infection. SVM classifier showed 81% sensitivity, 76% specificity, 66% PPV, 88% NPV, 80% accuracy, and 74% AUC in predicting THA infection in the training/validation/internal-testing cohort based on the only presence of periprosthetic bone marrow edema on MRI, while it showed 68% sensitivity, 89% specificity, 93% PPV, 60% NPV, 75% accuracy, and 79% AUC in the external-testing cohort. CONCLUSION: AI using SVM classifier showed promising results in predicting THA infection based on MRI features. This model might support radiologists in identifying THA infection.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Femenino , Humanos , Persona de Mediana Edad , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Inteligencia Artificial , Imagen por Resonancia Magnética/métodos , Algoritmos , Edema , Estudios Retrospectivos
5.
Radiol Med ; 128(8): 989-998, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37335422

RESUMEN

PURPOSE: To determine diagnostic performance of MRI radiomics-based machine learning for classification of deep-seated lipoma and atypical lipomatous tumor (ALT) of the extremities. MATERIAL AND METHODS: This retrospective study was performed at three tertiary sarcoma centers and included 150 patients with surgically treated and histology-proven lesions. The training-validation cohort consisted of 114 patients from centers 1 and 2 (n = 64 lipoma, n = 50 ALT). The external test cohort consisted of 36 patients from center 3 (n = 24 lipoma, n = 12 ALT). 3D segmentation was manually performed on T1- and T2-weighted MRI. After extraction and selection of radiomic features, three machine learning classifiers were trained and validated using nested fivefold cross-validation. The best-performing classifier according to previous analysis was evaluated and compared to an experienced musculoskeletal radiologist in the external test cohort. RESULTS: Eight features passed feature selection and were incorporated into the machine learning models. After training and validation (74% ROC-AUC), the best-performing classifier (Random Forest) showed 92% sensitivity and 33% specificity in the external test cohort with no statistical difference compared to the radiologist (p = 0.474). CONCLUSION: MRI radiomics-based machine learning may classify deep-seated lipoma and ALT of the extremities with high sensitivity and negative predictive value, thus potentially serving as a non-invasive screening tool to reduce unnecessary referral to tertiary tumor centers.


Asunto(s)
Lipoma , Liposarcoma , Humanos , Estudios Retrospectivos , Imagen por Resonancia Magnética , Liposarcoma/patología , Lipoma/diagnóstico por imagen , Extremidades , Aprendizaje Automático
6.
Eur J Nucl Med Mol Imaging ; 48(11): 3643-3655, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33959797

RESUMEN

OBJECTIVE: The objectives of our study were to assess the association of radiomic and genomic data with histology and patient outcome in non-small cell lung cancer (NSCLC). METHODS: In this retrospective single-centre observational study, we selected 151 surgically treated patients with adenocarcinoma or squamous cell carcinoma who performed baseline [18F] FDG PET/CT. A subgroup of patients with cancer tissue samples at the Institutional Biobank (n = 74/151) was included in the genomic analysis. Features were extracted from both PET and CT images using an in-house tool. The genomic analysis included detection of genetic variants, fusion transcripts, and gene expression. Generalised linear model (GLM) and machine learning (ML) algorithms were used to predict histology and tumour recurrence. RESULTS: Standardised uptake value (SUV) and kurtosis (among the PET and CT radiomic features, respectively), and the expression of TP63, EPHA10, FBN2, and IL1RAP were associated with the histotype. No correlation was found between radiomic features/genomic data and relapse using GLM. The ML approach identified several radiomic/genomic rules to predict the histotype successfully. The ML approach showed a modest ability of PET radiomic features to predict relapse, while it identified a robust gene expression signature able to predict patient relapse correctly. The best-performing ML radiogenomic rule predicting the outcome resulted in an area under the curve (AUC) of 0.87. CONCLUSIONS: Radiogenomic data may provide clinically relevant information in NSCLC patients regarding the histotype, aggressiveness, and progression. Gene expression analysis showed potential new biomarkers and targets valuable for patient management and treatment. The application of ML allows to increase the efficacy of radiogenomic analysis and provides novel insights into cancer biology.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/genética , Recurrencia Local de Neoplasia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Receptores de la Familia Eph , Estudios Retrospectivos , Transcriptoma
7.
Nucleic Acids Res ; 47(5): 2205-2215, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30657980

RESUMEN

MicroRNAs play important roles in many biological processes. Their aberrant expression can have oncogenic or tumor suppressor function directly participating to carcinogenesis, malignant transformation, invasiveness and metastasis. Indeed, miRNA profiles can distinguish not only between normal and cancerous tissue but they can also successfully classify different subtypes of a particular cancer. Here, we focus on a particular class of transcripts encoding polycistronic miRNA genes that yields multiple miRNA components. We describe 'clustered MiRNA Master Regulator Analysis (ClustMMRA)', a fully redesigned release of the MMRA computational pipeline (MiRNA Master Regulator Analysis), developed to search for clustered miRNAs potentially driving cancer molecular subtyping. Genomically clustered miRNAs are frequently co-expressed to target different components of pro-tumorigenic signaling pathways. By applying ClustMMRA to breast cancer patient data, we identified key miRNA clusters driving the phenotype of different tumor subgroups. The pipeline was applied to two independent breast cancer datasets, providing statistically concordant results between the two analyses. We validated in cell lines the miR-199/miR-214 as a novel cluster of miRNAs promoting the triple negative breast cancer (TNBC) phenotype through its control of proliferation and EMT.


Asunto(s)
Transición Epitelial-Mesenquimal/genética , MicroARNs/genética , Familia de Multigenes/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Línea Celular Tumoral , Proliferación Celular , Conjuntos de Datos como Asunto , Silenciador del Gen , Humanos , Invasividad Neoplásica/genética , Reproducibilidad de los Resultados , Neoplasias de la Mama Triple Negativas/clasificación
8.
Aging Clin Exp Res ; 33(6): 1709-1711, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31428998

RESUMEN

As claimed by Robert Gilles et al., "Images are more than pictures, they are data". This statement refers to the power of imaging to provide large amounts of quantitative features for improving diagnosis, prognosis and therapy response. The conversion of digital medical images into high-dimensional mineable data is called radiomics. Radiomics analysis is based on data-characterisation algorithms which have the potential to uncover disease heterogeneity characteristics that might escape from the expert evaluation. This method has been widely applied in oncology and genetic fields, while the literature on neurodegenerative disorders is in its relative infancy. Here, we provide a preliminary evaluation of the main results reached applying radiomics analyses on well-established MRI features of patients with Alzheimer's Disease and Parkinson's disease.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Parkinson , Algoritmos , Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Enfermedad de Parkinson/diagnóstico por imagen
9.
Int J Mol Sci ; 22(2)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445780

RESUMEN

MicroRNAs (miRNAs) are small noncoding RNAs that have emerged as new potential epigenetic biomarkers. Here, we evaluate the efficacy of six circulating miRNA previously described in the literature as biomarkers for the diagnosis of temporal lobe epilepsy (TLE) and/or as predictive biomarkers to antiepileptic drug response. We measured the differences in serum miRNA levels by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assays in a cohort of 27 patients (14 women and 13 men; mean ± SD age: 43.65 ± 17.07) with TLE compared to 20 healthy controls (HC) matched for sex, age and ethnicity (11 women and 9 men; mean ± SD age: 47.5 ± 9.1). Additionally, patients were classified according to whether they had drug-responsive (n = 17) or drug-resistant (n = 10) TLE. We have investigated any correlations between miRNAs and several electroclinical parameters. Three miRNAs (miR-142, miR-146a, miR-223) were significantly upregulated in patients (expressed as average expression ± SD). In detail, miR-142 expression was 0.40 ± 0.29 versus 0.16 ± 0.10 in TLE patients compared to HC (t-test, p < 0.01), miR-146a expression was 0.15 ± 0.11 versus 0.07 ± 0.04 (t-test, p < 0.05), and miR-223 expression was 6.21 ± 3.65 versus 1.23 ± 0.84 (t-test, p < 0.001). Moreover, results obtained from a logistic regression model showed the good performance of miR-142 and miR-223 in distinguishing drug-sensitive vs. drug-resistant TLE. The results of this pilot study give evidence that miRNAs are suitable targets in TLE and offer the rationale for further confirmation studies in larger epilepsy cohorts.


Asunto(s)
Biomarcadores/sangre , MicroARN Circulante/sangre , MicroARN Circulante/genética , Resistencia a Medicamentos/genética , Epilepsia del Lóbulo Temporal/sangre , Epilepsia del Lóbulo Temporal/genética , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Regulación hacia Arriba/genética
10.
Entropy (Basel) ; 23(2)2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670375

RESUMEN

The development of new computational approaches that are able to design the correct personalized drugs is the crucial therapeutic issue in cancer research. However, tumor heterogeneity is the main obstacle to developing patient-specific single drugs or combinations of drugs that already exist in clinics. In this study, we developed a computational approach that integrates copy number alteration, gene expression, and a protein interaction network of 73 basal breast cancer samples. 2509 prognostic genes harboring a copy number alteration were identified using survival analysis, and a protein-protein interaction network considering the direct interactions was created. Each patient was described by a specific combination of seven altered hub proteins that fully characterize the 73 basal breast cancer patients. We suggested the optimal combination therapy for each patient considering drug-protein interactions. Our approach is able to confirm well-known cancer related genes and suggest novel potential drug target genes. In conclusion, we presented a new computational approach in breast cancer to deal with the intra-tumor heterogeneity towards personalized cancer therapy.

11.
Medicina (Kaunas) ; 57(3)2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33809336

RESUMEN

Background and Objectives: Breast cancer is a heterogeneous disease categorized into four subtypes. Previous studies have shown that copy number alterations of several genes are implicated with the development and progression of many cancers. This study evaluates the effects of DNA copy number alterations on gene expression levels in different breast cancer subtypes. Materials and Methods: We performed a computational analysis integrating copy number alterations and gene expression profiles in 1024 breast cancer samples grouped into four molecular subtypes: luminal A, luminal B, HER2, and basal. Results: Our analyses identified several genes correlated in all subtypes such as KIAA1967 and MCPH1. In addition, several subtype-specific genes that showed a significant correlation between copy number and gene expression profiles were detected: SMARCB1, AZIN1, MTDH in luminal A, PPP2R5E, APEX1, GCN5 in luminal B, TNFAIP1, PCYT2, DIABLO in HER2, and FAM175B, SENP5, SCAF1 in basal subtype. Conclusions: This study showed that computational analyses integrating copy number and gene expression can contribute to unveil the molecular mechanisms of cancer and identify new subtype-specific biomarkers.


Asunto(s)
Neoplasias de la Mama , Variaciones en el Número de Copia de ADN , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Variaciones en el Número de Copia de ADN/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas de la Membrana , Proteína Fosfatasa 2 , Proteínas de Unión al ARN , Transcriptoma/genética
12.
Cereb Cortex ; 29(12): 4948-4957, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-30877789

RESUMEN

Brain energy metabolism actively regulates synaptic transmission and activity. We have previously shown that acute footshock (FS)-stress induces fast and long-lasting functional and morphological changes at excitatory synapses in prefrontal cortex (PFC). Here, we asked whether FS-stress increased energy metabolism in PFC, and modified related cognitive functions. Using positron emission tomography (PET), we found that FS-stress induced a redistribution of glucose metabolism in the brain, with relative decrease of [18F]FDG uptake in ventro-caudal regions and increase in dorso-rostral ones. Absolute [18F]FDG uptake was inversely correlated with serum corticosterone. Increased specific hexokinase activity was also measured in purified PFC synaptosomes (but not in total extract) of FS-stressed rats, which positively correlated with 2-Deoxy [3H] glucose uptake by synaptosomes. In line with increased synaptic energy demand, using an electron microscopy-based stereological approach, we found that acute stress induced a redistribution of mitochondria at excitatory synapses, together with an increase in their volume. The fast functional and metabolic activation of PFC induced by acute stress, was accompanied by rapid and sustained alterations of working memory performance in delayed response to T-maze test. Taken together, the present data suggest that acute stress increases energy consumption at PFC synaptic terminals and alters working memory.


Asunto(s)
Metabolismo Energético/fisiología , Memoria a Corto Plazo/fisiología , Corteza Prefrontal/metabolismo , Estrés Psicológico/metabolismo , Sinapsis/metabolismo , Animales , Masculino , Tomografía de Emisión de Positrones , Ratas , Ratas Sprague-Dawley
13.
Eur J Nucl Med Mol Imaging ; 46(13): 2673-2699, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31292700

RESUMEN

INTRODUCTION: The quantitative imaging features (radiomics) that can be obtained from the different modalities of current-generation hybrid imaging can give complementary information with regard to the tumour environment, as they measure different morphologic and functional imaging properties. These multi-parametric image descriptors can be combined with artificial intelligence applications into predictive models. It is now the time for hybrid PET/CT and PET/MRI to take the advantage offered by radiomics to assess the added clinical benefit of using multi-parametric models for the personalized diagnosis and prognosis of different disease phenotypes. OBJECTIVE: The aim of the paper is to provide an overview of current challenges and available solutions to translate radiomics into hybrid PET-CT and PET-MRI imaging for a smart and truly multi-parametric decision model.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen Multimodal , Algoritmos , Toma de Decisiones , Humanos
14.
Int J Mol Sci ; 20(23)2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31756987

RESUMEN

Personalized medicine relies on the integration and consideration of specific characteristics of the patient, such as tumor phenotypic and genotypic profiling. BACKGROUND: Radiogenomics aim to integrate phenotypes from tumor imaging data with genomic data to discover genetic mechanisms underlying tumor development and phenotype. METHODS: We describe a computational approach that correlates phenotype from magnetic resonance imaging (MRI) of breast cancer (BC) lesions with microRNAs (miRNAs), mRNAs, and regulatory networks, developing a radiomiRNomic map. We validated our approach to the relationships between MRI and miRNA expression data derived from BC patients. We obtained 16 radiomic features quantifying the tumor phenotype. We integrated the features with miRNAs regulating a network of pathways specific for a distinct BC subtype. RESULTS: We found six miRNAs correlated with imaging features in Luminal A (miR-1537, -205, -335, -337, -452, and -99a), seven miRNAs (miR-142, -155, -190, -190b, -1910, -3617, and -429) in HER2+, and two miRNAs (miR-135b and -365-2) in Basal subtype. We demonstrate that the combination of correlated miRNAs and imaging features have better classification power of Luminal A versus the different BC subtypes than using miRNAs or imaging alone. CONCLUSION: Our computational approach could be used to identify new radiomiRNomic profiles of multi-omics biomarkers for BC differential diagnosis and prognosis.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/diagnóstico , Aprendizaje Automático , MicroARNs/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/genética , Femenino , Redes Reguladoras de Genes , Humanos , Imagen por Resonancia Magnética , MicroARNs/metabolismo , Transcriptoma
15.
BMC Genomics ; 19(1): 25, 2018 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-29304754

RESUMEN

BACKGROUND: Modern high-throughput genomic technologies represent a comprehensive hallmark of molecular changes in pan-cancer studies. Although different cancer gene signatures have been revealed, the mechanism of tumourigenesis has yet to be completely understood. Pathways and networks are important tools to explain the role of genes in functional genomic studies. However, few methods consider the functional non-equal roles of genes in pathways and the complex gene-gene interactions in a network. RESULTS: We present a novel method in pan-cancer analysis that identifies de-regulated genes with a functional role by integrating pathway and network data. A pan-cancer analysis of 7158 tumour/normal samples from 16 cancer types identified 895 genes with a central role in pathways and de-regulated in cancer. Comparing our approach with 15 current tools that identify cancer driver genes, we found that 35.6% of the 895 genes identified by our method have been found as cancer driver genes with at least 2/15 tools. Finally, we applied a machine learning algorithm on 16 independent GEO cancer datasets to validate the diagnostic role of cancer driver genes for each cancer. We obtained a list of the top-ten cancer driver genes for each cancer considered in this study. CONCLUSIONS: Our analysis 1) confirmed that there are several known cancer driver genes in common among different types of cancer, 2) highlighted that cancer driver genes are able to regulate crucial pathways.


Asunto(s)
Biomarcadores de Tumor/genética , Redes Reguladoras de Genes , Genómica/métodos , Neoplasias/genética , Transducción de Señal , Algoritmos , Estudios de Casos y Controles , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos
16.
J Transl Med ; 16(1): 154, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29871693

RESUMEN

BACKGROUND: Despite great development in genome and proteome high-throughput methods, treatment failure is a critical point in the management of most solid cancers, including breast cancer (BC). Multiple alternative mechanisms upon drug treatment are involved to offset therapeutic effects, eventually causing drug resistance or treatment failure. METHODS: Here, we optimized a computational method to discover novel drug target pathways in cancer subtypes using pathway cross-talk inhibition (PCI). The in silico method is based on the detection and quantification of the pathway cross-talk for distinct cancer subtypes. From a BC data set of The Cancer Genome Atlas, we have identified different networks of cross-talking pathways for different BC subtypes, validated using an independent BC dataset from Gene Expression Omnibus. Then, we predicted in silico the effects of new or approved drugs on different BC subtypes by silencing individual or combined subtype-derived pathways with the aim to find new potential drugs or more effective synergistic combinations of drugs. RESULTS: Overall, we identified a set of new potential drug target pathways for distinct BC subtypes on which therapeutic agents could synergically act showing antitumour effects and impacting on cross-talk inhibition. CONCLUSIONS: We believe that in silico methods based on PCI could offer valuable approaches to identifying more tailored and effective treatments in particular in heterogeneous cancer diseases.


Asunto(s)
Neoplasias de la Mama/clasificación , Neoplasias de la Mama/patología , Simulación por Computador , Sistemas de Liberación de Medicamentos , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Receptor ErbB-2/metabolismo , Reproducibilidad de los Resultados
17.
Nucleic Acids Res ; 44(8): e71, 2016 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-26704973

RESUMEN

The Cancer Genome Atlas (TCGA) research network has made public a large collection of clinical and molecular phenotypes of more than 10 000 tumor patients across 33 different tumor types. Using this cohort, TCGA has published over 20 marker papers detailing the genomic and epigenomic alterations associated with these tumor types. Although many important discoveries have been made by TCGA's research network, opportunities still exist to implement novel methods, thereby elucidating new biological pathways and diagnostic markers. However, mining the TCGA data presents several bioinformatics challenges, such as data retrieval and integration with clinical data and other molecular data types (e.g. RNA and DNA methylation). We developed an R/Bioconductor package called TCGAbiolinks to address these challenges and offer bioinformatics solutions by using a guided workflow to allow users to query, download and perform integrative analyses of TCGA data. We combined methods from computer science and statistics into the pipeline and incorporated methodologies developed in previous TCGA marker studies and in our own group. Using four different TCGA tumor types (Kidney, Brain, Breast and Colon) as examples, we provide case studies to illustrate examples of reproducibility, integrative analysis and utilization of different Bioconductor packages to advance and accelerate novel discoveries.


Asunto(s)
Biología Computacional/métodos , Minería de Datos/métodos , Bases de Datos Genéticas , Genoma Humano/genética , Genómica/métodos , Neoplasias/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Biomarcadores de Tumor/genética , Metilación de ADN/genética , Humanos , Neoplasias/clasificación , Estadística como Asunto/métodos
18.
Int J Mol Sci ; 19(3)2018 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-29562723

RESUMEN

Like other cancer diseases, prostate cancer (PC) is caused by the accumulation of genetic alterations in the cells that drives malignant growth. These alterations are revealed by gene profiling and copy number alteration (CNA) analysis. Moreover, recent evidence suggests that also microRNAs have an important role in PC development. Despite efforts to profile PC, the alterations (gene, CNA, and miRNA) and biological processes that correlate with disease development and progression remain partially elusive. Many gene signatures proposed as diagnostic or prognostic tools in cancer poorly overlap. The identification of co-expressed genes, that are functionally related, can identify a core network of genes associated with PC with a better reproducibility. By combining different approaches, including the integration of mRNA expression profiles, CNAs, and miRNA expression levels, we identified a gene signature of four genes overlapping with other published gene signatures and able to distinguish, in silico, high Gleason-scored PC from normal human tissue, which was further enriched to 19 genes by gene co-expression analysis. From the analysis of miRNAs possibly regulating this network, we found that hsa-miR-153 was highly connected to the genes in the network. Our results identify a four-gene signature with diagnostic and prognostic value in PC and suggest an interesting gene network that could play a key regulatory role in PC development and progression. Furthermore, hsa-miR-153, controlling this network, could be a potential biomarker for theranostics in high Gleason-scored PC.


Asunto(s)
Simulación por Computador , Redes Reguladoras de Genes , MicroARNs/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Adulto , Anciano , Área Bajo la Curva , Variaciones en el Número de Copia de ADN/genética , Regulación hacia Abajo/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Invasividad Neoplásica , Regulación hacia Arriba/genética
19.
Int J Mol Sci ; 19(4)2018 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-29617354

RESUMEN

BACKGROUND: There is extensive scientific evidence that radiation therapy (RT) is a crucial treatment, either alone or in combination with other treatment modalities, for many types of cancer, including breast cancer (BC). BC is a heterogeneous disease at both clinical and molecular levels, presenting distinct subtypes linked to the hormone receptor (HR) status and associated with different clinical outcomes. The aim of this study was to assess the molecular changes induced by high doses of ionizing radiation (IR) on immortalized and primary BC cell lines grouped according to Human epidermal growth factor receptor (HER2), estrogen, and progesterone receptors, to study how HR status influences the radiation response. Our genomic approach using in vitro and ex-vivo models (e.g., primary cells) is a necessary first step for a translational study to describe the common driven radio-resistance features associated with HR status. This information will eventually allow clinicians to prescribe more personalized total doses or associated targeted therapies for specific tumor subtypes, thus enhancing cancer radio-sensitivity. METHODS: Nontumorigenic (MCF10A) and BC (MCF7 and MDA-MB-231) immortalized cell lines, as well as healthy (HMEC) and BC (BCpc7 and BCpcEMT) primary cultures, were divided into low grade, high grade, and healthy groups according to their HR status. At 24 h post-treatment, the gene expression profiles induced by two doses of IR treatment with 9 and 23 Gy were analyzed by cDNA microarray technology to select and compare the differential gene and pathway expressions among the experimental groups. RESULTS: We present a descriptive report of the substantial alterations in gene expression levels and pathways after IR treatment in both immortalized and primary cell cultures. Overall, the IR-induced gene expression profiles and pathways appear to be cell-line dependent. The data suggest that some specific gene and pathway signatures seem to be linked to HR status. CONCLUSIONS: Genomic biomarkers and gene-signatures of specific tumor subtypes, selected according to their HR status and molecular features, could facilitate personalized biological-driven RT treatment planning alone and in combination with targeted therapies.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Radiación Ionizante , Neoplasias de la Mama/metabolismo , Línea Celular Transformada , Línea Celular Tumoral , Biología Computacional/métodos , Relación Dosis-Respuesta en la Radiación , Femenino , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Clasificación del Tumor , Dosis de Radiación , Tolerancia a Radiación/genética , Transducción de Señal , Transcriptoma
20.
Breast Cancer Res Treat ; 161(3): 605-616, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28000015

RESUMEN

PURPOSE: We demonstrated that Hsa-miR-567 expression is significantly downregulated in poor prognosis breast cancer, compared to better prognosis breast cancer, having a role in the control of cell proliferation and migration by regulating KPNA4 gene. METHODS AND RESULTS: In this study, based on our previously published in silico results, we proved both in vitro (cell line studies) and ex vivo (clinical studies), that Hsa-miR-567 expression is significantly downregulated in breast cancer with poor prognosis when compared to breast cancer with better prognosis. More intriguingly, we demonstrated that the ectopic expression of Hsa-miR-567 in poor prognosis breast cancer cell line strongly inhibits in vitro cell proliferation and migration. Furthermore, we showed in vivo that breast cancer cells, stably expressing Hsa-miR-567, xenografted in mouse, reduce tumor growth ability. Consistently, we found that karyopherin 4 (KPNA4), predicted target gene of Hsa-miR-567 as identified by our in silico analysis, is upregulated in highly aggressive MDA-MB-231 breast cancer cell line and patient tissues with poor prognosis with respect to good prognosis. CONCLUSIONS: Our results suggest a potential role of Hsa-miR-567 as a novel prognostic biomarker for BC and as regulator of KPNA4.


Asunto(s)
Neoplasias de la Mama/genética , Carcinogénesis/genética , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , MicroARNs/genética , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Biología Computacional/métodos , Modelos Animales de Enfermedad , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Xenoinjertos , Humanos , Ratones , Interferencia de ARN , Reproducibilidad de los Resultados , Carga Tumoral , alfa Carioferinas/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA