Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Int J Mol Sci ; 24(12)2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37373295

RESUMEN

Circulating tumor cells (CTCs) are one of the most important causes of tumor recurrence and distant metastases. Glioblastoma (GBM) has been considered restricted to the brain for many years. Nevertheless, in the past years, several pieces of evidence indicate that hematogenous dissemination is a reality, and this is also in the caseof GBM. Our aim was to optimize CTCs' detection in GBM and define the genetic background of single CTCs compared to the primary GBM tumor and its recurrence to demonstrate that CTCs are indeed derived from the parental tumor. We collected blood samples from a recurrent IDH wt GBM patient. We genotyped the parental recurrent tumor tissue and the respective primary GBM tissue. CTCs were analyzed using the DEPArray system. CTCs Copy Number Alterations (CNAs) and sequencing analyses were performed to compare CTCs' genetic background with the same patient's primary and recurrent GBM tissues. We identified 210 common mutations in the primary and recurrent tumors. Among these, three somatic high-frequency mutations (in PRKCB, TBX1, and COG5 genes) were selected to investigate their presence in CTCs. Almost all sorted CTCs (9/13) had at least one of the mutations tested. The presence of TERT promoter mutations was also investigated and C228T variation was found in parental tumors and CTCs (C228T heterozygous and homozygous, respectively). We were able to isolate and genotype CTCs from a patient with GBM. We found common mutations but also exclusive molecular characteristics.


Asunto(s)
Glioblastoma , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Glioblastoma/genética , Glioblastoma/patología , Recurrencia Local de Neoplasia/genética , Mutación , Genotipo
2.
Curr Opin Oncol ; 34(6): 705-712, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36093876

RESUMEN

PURPOSE OF REVIEW: Gliomas are the most common primary tumors of the central nervous system. They are characterized by a disappointing prognosis and ineffective therapy that has shown no substantial improvements in the past 20 years. The lack of progress in treating gliomas is linked with the inadequacy of suitable tumor samples to plan translational studies and support laboratory developments. To overcome the use of tumor tissue, this commentary review aims to highlight the potential for the clinical application of liquid biopsy (intended as the study of circulating biomarkers in the blood), focusing on circulating tumor cells, circulating DNA and circulating noncoding RNA. RECENT FINDINGS: Thanks to the increasing sensitivity of sequencing techniques, it is now possible to analyze circulating nucleic acids and tumor cells (liquid biopsy). SUMMARY: Although studies on the use of liquid biopsy are still at an early stage, the potential clinical applications of liquid biopsy in the study of primary brain cancer are many and have the potential to revolutionize the approach to neuro-oncology, and importantly, they offer the possibility of gathering information on the disease at any time during its history.


Asunto(s)
Ácidos Nucleicos Libres de Células , Glioma , Células Neoplásicas Circulantes , Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Glioma/diagnóstico , Humanos , Biopsia Líquida/métodos , Células Neoplásicas Circulantes/patología , ARN no Traducido
3.
Int J Mol Sci ; 23(11)2022 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-35682658

RESUMEN

Glioblastoma (GBM) is the most common form of malignant brain cancer and is considered the deadliest human cancer. Because of poor outcomes in this disease, there is an urgent need for progress in understanding the molecular mechanisms of GBM therapeutic resistance, as well as novel and innovative therapies for cancer prevention and treatment. The pentose phosphate pathway (PPP) is a metabolic pathway complementary to glycolysis, and several PPP enzymes have already been demonstrated as potential targets in cancer therapy. In this work, we aimed to evaluate the role of sedoheptulose kinase (SHPK), a key regulator of carbon flux that catalyzes the phosphorylation of sedoheptulose in the nonoxidative arm of the PPP. SHPK expression was investigated in patients with GBM using microarray data. SHPK was also overexpressed in GBM cells, and functional studies were conducted. SHPK expression in GBM shows a significant correlation with histology, prognosis, and survival. In particular, its increased expression is associated with a worse prognosis. Furthermore, its overexpression in GBM cells confirms an increase in cell proliferation. This work highlights for the first time the importance of SHPK in GBM for tumor progression and proposes this enzyme and the nonoxidative PPP as possible therapeutic targets.


Asunto(s)
Glioblastoma , Vía de Pentosa Fosfato , Proliferación Celular , Glioblastoma/genética , Glioblastoma/metabolismo , Heptosas , Humanos
4.
Invest New Drugs ; 39(4): 1159-1165, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33558989

RESUMEN

This study reports the results of a monocentric prospective analysis conducted with the aim of evaluating the impact of XRCC1 rs25487, XRCC3 rs861539, XRCC3 rs1799794, RAD51 rs1801320 and GSTP-1 rs1695 single nucleotide polymorphisms (SNP) on patients with high-grade glioma treated with concomitant radio-chemotherapy. From October 2010 to August 2019, a total of 75 patients aged ≥18 years, with histological diagnosis of high-grade glioma, isocitrate dehydrogenase (IDH) 1/2 wild type and treated with radio-chemotherapy and sequential chemotherapy with temozolomide (TMZ) were prospectively recruited. The local ethic committee approved this study (Comitato Etico di Area Vasta Nord Ovest [CEAVNO]; protocol 3304/2011). After a median follow up of 25 months (range: 7-98 months), median progression-free survival (PFS) and overall survival (OS) were 11 months (CI95%: 8-14 months) and 18 months (CI95%: 15-21 months), respectively. In univariate and multivariate Cox regression analysis, a statistically significant association with PFS and OS was found with XRCC3 rs1799794 SNP. The study suggests that XRCC3 rs1799794 SNP can be associated with different PFS and OS in glioblastoma patients treated with radio-chemotherapy.


Asunto(s)
Neoplasias Encefálicas/terapia , Quimioradioterapia/métodos , Proteínas de Unión al ADN/genética , Glioblastoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/genética , Femenino , Estudios de Seguimiento , Glioblastoma/genética , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Supervivencia sin Progresión , Estudios Prospectivos , Tasa de Supervivencia , Resultado del Tratamiento
5.
Biom J ; 62(7): 1810-1825, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32596846

RESUMEN

The estimation of individual values (marks) in a finite population of units (e.g., trees) scattered onto a survey region is considered under 3P sampling. For each unit, the mark is estimated by means of an inverse distance weighting interpolator. Conditions ensuring the design-based consistency of maps are considered under 3P sampling. A computationally simple mean squared error estimator is adopted. Because 3P sampling involves the prediction of marks for each unit in the population, prediction errors rather than marks can be interpolated. Then, marks are estimated by the predictions plus the interpolated errors. If predictions are good, prediction errors are more smoothed than raw marks so that the procedure is likely to better meet consistency requirements. The purpose of this paper is to provide theoretical and empirical evidence on the effectiveness of the interpolation based on prediction errors to prove that the proposed strategy is a tool of general validity for mapping forest stands.


Asunto(s)
Estadística como Asunto , Árboles , Ecología
6.
Cancer Cell Int ; 19: 223, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31467489

RESUMEN

BACKGROUND: Neoplastic cells promote a hypercoagulable state by the expression of cell surface proteins, such as tissue factor. In BRAFv600 mutated melanoma patients upon BRAF inhibitors, a hypercoagulable state correlates with prognosis, while a down-regulation of the hemostatic parameters is observed in patients responders as compared to non responders. The present study was intended to better clarify the strict relationship between coagulation mediators and target therapy in melanoma. METHODS: The expression of tissue factor was investigated after the treatment with the BRAF inhibitor Dabrafenib and the MEK inhibitor Trametinib in the BRAFv600e mutated melanoma cell lines A-375 and SK-MEL-28, together with its ability to activate the coagulation cascade. RESULTS: Dabrafenib and Trametinib caused the down-regulation of TF in both cell lines A-375 and SK-MEL-28. For the cell line A-375 the effect was evident both at RNA and procoagulant activity; for the cell line SK-MEL-28 only at RNA level without any variation of the protein. Interestingly, when in contact with plasma deficient of factor VII, both cell lines were not able to activate the coagulation cascade. CONCLUSIONS: The present study provides the first in vitro observation that tissue factor expressed in melanoma cells may contribute to the modulation of the coagulation state of patients in the treatment with BRAF inhibitors.

7.
Biom J ; 61(1): 166-186, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30350413

RESUMEN

The estimation of the values of a variable at any point of a study area is performed using Bernstein polynomials when the sampling scheme is implemented by selecting a point in each polygon of a regular grid overimposed onto the area. The evaluation of the precision of the resulting estimates is investigated under a completely design-based framework. Moreover, as the main contribution to the mean squared error of the Bernstein-type estimator is due to the bias, also a pseudo-jackknife estimator is proposed. The performance of both estimators is investigated theoretically and by means of a simulation study. An application to a soil survey performed in Berkshire Downs in Oxfordshire (UK) is considered.


Asunto(s)
Estadística como Asunto/métodos , Concentración de Iones de Hidrógeno , Suelo/química
8.
Invest New Drugs ; 36(2): 340-345, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28965273

RESUMEN

Glioblastoma (GBM) is the most frequent malignant primary brain tumor in adults and, despite recent advances, the prognosis for this cancer remains dismal. The aims of this study were to test the influence of XRCC1 rs25487, XRCC3 rs861539, XRCC3 rs1799794, RAD51 rs1801320 and GSTP-1 rs1695 single nucleotide polymorphisms on progression free survival (PFS) and overall survival (OS) in GBM patients treated with radiotherapy (RT) and temozolomide (TMZ). Fifty GBM patients treated with upfront radio-chemotherapy (RT 60 Gy/30 sessions; TMZ 75 mg/m2 during RT and 200 mg/m2 days 1 â†’ 5 every 28 days) were enrolled. Survival curves were calculated using the Kaplan-Meier method, and the log-rank test was used to evaluate differences between curves. A trend to a statistically significant association with PFS in univariate and multivariate COX regression analysis was found with GSTP-1 rs1695 polymorphism (p = 0.087 and p = 0.097 on univariate and multivariate analyses, respectively). Conversely, the same GSTP-1 rs1695 SNP revealed a statistically significant association with OS (p = 0.007 and p = 0.042 on univariate and multivariate analysis, respectively). Our pharmacogenetic prospective study suggests that GSTP-1 rs1695 genotypes can be associated with different OS in GBM patients treated with RT and TMZ.


Asunto(s)
Quimioradioterapia , Estudios de Asociación Genética , Glioblastoma/genética , Glioblastoma/terapia , Gutatión-S-Transferasa pi/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Glioblastoma/enzimología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Análisis de Supervivencia
9.
BMC Neurol ; 18(1): 99, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30029642

RESUMEN

BACKGROUND: Leigh Syndrome (LS, OMIM 256000) is an early-onset, progressive neurodegenerative disorder characterized by broad clinical and genetic heterogeneity; it is the most frequent disorder of mitochondrial energy production in children. LS inheritance is complex because patients may present mutations in mitochondrial DNA (mtDNA) or in nuclear genes, which predominantly encode proteins involved in respiratory chain structure and assembly or in coenzyme Q10 biogenesis. However, during the last 15 years, the discovery of several genetic mutations and improved knowledge of the natural history of LS has significantly increased our understanding of this mitochondrial disorder. CASE PRESENTATION: Here we describe a 19-year-old male with clinical and neuroimaging LS diagnosed at 3 years of age. Genetic analyses of the whole mtDNA for maternally inherited LS (MILS) and neuropathy ataxia retinitis pigmentosa (NARP) syndrome failed to reveal any pathogenic mutations. CONCLUSIONS: Recently, a missense mutation in ECHS1 and a ~ 35 kb deletion in 10q26.3 involving the region including the gene were identified by WES (whole exome sequencing), uncovering the genetic diagnosis clinically hypothesized for 15 years. We also report the long-term follow-up of this patient, showing a comparison with classical LS or other Leigh-like pictures.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedad de Leigh , Secuenciación Completa del Genoma , Adolescente , Heterogeneidad Genética , Humanos , Enfermedad de Leigh/diagnóstico , Enfermedad de Leigh/genética , Masculino
10.
Carcinogenesis ; 38(9): 938-943, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28911001

RESUMEN

Li-Fraumeni syndrome is a clinically heterogeneous familial cancer predisposition syndrome with autosomal-dominant inheritance caused by heterozygous germline mutations in the TP53 gene. We here analyze the genetic background of a family with a 4-year-proband presented with a Li-Fraumeni tumor. The mother developed breast cancer at age 37 and the proband died at age 8. We performed Sanger sequencing and whole-exome sequencing on peripheral blood DNA from proband and relatives. Data analysis selected only high-quality score and depth reads, rare variants and protein impact involving missense, non-sense, frameshift and splice disrupt mutations. Disease implicated variants and predicted deleterious alterations were also chosen. TP53 genetic testing revealed a never reported TP53 deletion arose as de novo mutation in the mother and inherited by the proband. We then performed whole-exome analysis of the trio to uncover inherited variants from the father that potentially worsen the already altered genetic background in the proband. No pathogenic variants were inherited in autosomal recessive, de novo dominant or X-linked recessive manner. Comparing proband and father exome we detected 25 predicted deleterious variants including a nonsense mutation in ERCC3. Those inherited mutations are possible candidate modifiers linked to TP53, explaining the proband accelerated tumor onset compared to the mother and providing a possible explanation of the genetic anticipation event in this Li-Fraumeni family.


Asunto(s)
Anticipación Genética , Neoplasias de la Mama/genética , Síndrome de Li-Fraumeni/genética , Proteína p53 Supresora de Tumor/genética , Carcinoma Corticosuprarrenal/terapia , Preescolar , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Exoma/genética , Femenino , Genes p53 , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Mutación de Línea Germinal , Heterocigoto , Humanos , Metástasis Linfática , Masculino , Linaje , Análisis de Secuencia de ADN , Eliminación de Secuencia
11.
J Med Genet ; 53(4): 242-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26729821

RESUMEN

BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare autosomal recessive genetic disorder characterised by dysfunction of motile cilia. Ciliary dysmotility causes poor mucociliary clearance and leads to impairment of pulmonary function and severe respiratory infections. PCD has no specific therapy. With the aim to permanently restore gene function and normalise ciliary motility, we used gene editing to replace mutated with wild-type sequence in defective cells. METHODS: The target gene was dynein heavy chain 11 (DNAH11), an essential component of ciliary structure. Airway ciliated cells were collected from two patients with PCD with DNAH11 nonsense mutations and altered ciliary beating and pattern. Repair of the genetic defect was performed ex vivo by site-specific recombination using transcription activator-like effector nucleases (TALENs). RESULTS: In an epithelial cell line engineered to contain the DNAH11 target site, TALENs cleaved over 80% of the mutated DNAH11 sequence and replaced the mutated sequence with wild-type sequence in about 50% of cells. In airway ciliated cells of patients with PCD, site-specific recombination and normalisation of ciliary beating and pattern occurred in 33% and 29% of cells, respectively. CONCLUSION: This study demonstrates that gene editing can rescue ciliary beating ex vivo, opening up new avenues for treating PCD.


Asunto(s)
Dineínas Axonemales/genética , Edición Génica , Terapia Genética , Síndrome de Kartagener/terapia , Adolescente , Línea Celular , Movimiento Celular/genética , Cilios/metabolismo , Cilios/patología , Células Epiteliales/patología , Genotipo , Humanos , Síndrome de Kartagener/genética , Síndrome de Kartagener/patología , Lentivirus/genética , Masculino , Fenotipo , Gemelos
12.
J Transl Med ; 14(1): 248, 2016 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-27567668

RESUMEN

AIMS: Myocardial fibrosis (MF) is a deleterious consequence of aortic valve stenosis (AVS). Global longitudinal strain (GLS) is a novel left ventricular (LV) functional parameter potentially useful to non-invasively estimate MF. MicroRNAs (miRNAs) are non-coding small ribonucleic acids (RNA) modulating genes function, mainly through RNA degradation. miRNA-21 is a biomarker associated with MF in pressure overload. The aim of the present study was to find an integrated algorithm for detection of MF using a combined approach with both bio- and functional markers. METHODS: Thirty-six patients (75.2 ± 8 y.o.; 63 % Female) with severe AVS and preserved LV ejection fraction (EF), candidate to surgical aortic valve replacement (sAVR) were enrolled. Clinical, bio-humoral evaluation (including plasmatic miRNA-21 collected using specific tubes, PAXgene, for stabilization of peripheral RNA) and a complete echocardiographic study, including GLS and septal strain, were performed before sAVR. Twenty-eight of those patients underwent sAVR and, in 23 of them, an inter-ventricular septum biopsy was performed. Tissues were fixed in formalin and embedded in paraffin. Sections were stained with Hematoxylin and Eosin for histological evaluation and with histochemical Masson trichrome for collagen fibers. The different components were calculated and expressed as micrometers(2). To evaluate tissue miRNA components, sections 2-µm thick were cut using a microtome blade for each slide. Regression analysis was performed to test association between dependent variable and various predictors included in the model. RESULTS: Despite a preserved EF (66 ± 11 %), patients presented altered myocardial deformation parameters (GLS -14,02 ± 3.8 %; septal longitudinal strain, SSL -9.63 ± 2.9 %; septal longitudinal strain rate, SL-Sr -0.58 ± 0.17 1/s; Septal Longitudinal early-diastolic strain rate, SL-SrE 0.62 ± 0.32 1/s). The extent of MF showed an inverse association with both GLS and septal longitudinal deformation indices (GLS: R(2) = 0.30; p = 0.02; SSL: R(2) = 0.36; p = 0.01; SL-Sr: R(2) = 0.39; p < 0.001; SL-SrE: R(2) = 0.35; p = 0.001). miRNA-21 was mainly expressed in fibrous tissue (p < 0.0001). A significant association between MF and plasmatic miRNA-21, alone and weighted for measures of structural (LVMi R(2) = 0.50; p = 0.0005) and functional (SSL R(2) = 0.35; p = 0.006) remodeling, was found. CONCLUSIONS: In AVS, MF is associated with alterations of regional and global strain. Plasmatic miRNA-21 is directly related to MF and associated with LV structural and functional impairment.


Asunto(s)
Estenosis de la Válvula Aórtica/genética , Estenosis de la Válvula Aórtica/fisiopatología , MicroARNs/genética , Miocardio/metabolismo , Miocardio/patología , Índice de Severidad de la Enfermedad , Anciano , Estenosis de la Válvula Aórtica/sangre , Estenosis de la Válvula Aórtica/patología , Biomarcadores , Femenino , Fibrosis , Humanos , Masculino , MicroARNs/sangre , Proyectos Piloto , Análisis de Regresión
14.
BMC Cancer ; 15: 918, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26581891

RESUMEN

BACKGROUND: Papillary thyroid cancer is the most common endocrine malignancy. The most sensitive and specific diagnostic tool for thyroid nodule diagnosis is fine-needle aspiration (FNA) biopsy with cytological evaluation. Nevertheless, FNA biopsy is not always decisive leading to "indeterminate" or "suspicious" diagnoses in 10%-30% of cases. BRAF V600E detection is currently used as molecular test to improve the diagnosis of thyroid nodules, yet it lacks sensitivity. The aim of the present study was to identify novel molecular markers/computational models to improve the discrimination between benign and malignant thyroid lesions. METHODS: We collected 118 pre-operative thyroid FNA samples. All 118 FNA samples were characterized for the presence of the BRAF V600E mutation (exon15) by pyrosequencing and further assessed for mRNA expression of four genes (KIT, TC1, miR-222, miR-146b) by quantitative polymerase chain reaction. Computational models (Bayesian Neural Network Classifier, discriminant analysis) were built, and their ability to discriminate benign and malignant tumors were tested. Receiver operating characteristic (ROC) analysis was performed and principal component analysis was used for visualization purposes. RESULTS: In total, 36/70 malignant samples carried the V600E mutation, while all 48 benign samples were wild type for BRAF exon15. The Bayesian neural network (BNN) and discriminant analysis, including the mRNA expression of the four genes (KIT, TC1, miR-222, miR-146b) showed a very strong predictive value (94.12% and 92.16%, respectively) in discriminating malignant from benign patients. The discriminant analysis showed a correct classification of 100% of the samples in the malignant group, and 95% by BNN. KIT and miR-146b showed the highest diagnostic accuracy of the ROC curve, with area under the curve values of 0.973 for KIT and 0.931 for miR-146b. CONCLUSIONS: The four genes model proposed in this study proved to be highly discriminative of the malignant status compared with BRAF assessment alone. Its implementation in clinical practice can help in identifying malignant/benign nodules that would otherwise remain suspicious.


Asunto(s)
Biomarcadores de Tumor/genética , MicroARNs/genética , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas c-kit/genética , Neoplasias de la Tiroides/diagnóstico , Anciano , Teorema de Bayes , Biomarcadores de Tumor/metabolismo , Biopsia con Aguja Fina , Femenino , Perfilación de la Expresión Génica , Marcadores Genéticos , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Mutación , Proteínas de Neoplasias/metabolismo , Análisis de Componente Principal , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , ARN/metabolismo , ARN Mitocondrial , Curva ROC , Sensibilidad y Especificidad , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/metabolismo
15.
Cells ; 13(6)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38534332

RESUMEN

Glioblastoma, a deadly brain tumor, shows limited response to standard therapies like temozolomide (TMZ). Recent findings from the REGOMA trial underscore a significant survival improvement offered by Regorafenib (REGO) in recurrent glioblastoma. Our study aimed to propose a 3D ex vivo drug response precision medicine approach to investigate recurrent glioblastoma sensitivity to REGO and elucidate the underlying molecular mechanisms involved in tumor resistance or responsiveness to treatment. Three-dimensional glioblastoma organoids (GB-EXPs) obtained from 18 patients' resected recurrent glioblastoma tumors were treated with TMZ and REGO. Drug responses were evaluated using NAD(P)H FLIM, stratifying tumors as responders (Resp) or non-responders (NRs). Whole-exome sequencing was performed on 16 tissue samples, and whole-transcriptome analysis on 13 GB-EXPs treated and untreated. We found 35% (n = 9) and 77% (n = 20) of tumors responded to TMZ and REGO, respectively, with no instances of TMZ-Resp being REGO-NRs. Exome analysis revealed a unique mutational profile in REGO-Resp tumors compared to NR tumors. Transcriptome analysis identified distinct expression patterns in Resp and NR tumors, impacting Rho GTPase and NOTCH signaling, known to be involved in drug response. In conclusion, recurrent glioblastoma tumors were more responsive to REGO compared to TMZ treatment. Importantly, our approach enables a comprehensive longitudinal exploration of the molecular changes induced by treatment, unveiling promising biomarkers indicative of drug response.


Asunto(s)
Glioblastoma , Compuestos de Fenilurea , Piridinas , Humanos , Antineoplásicos Alquilantes/farmacología , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Recurrencia Local de Neoplasia/patología , Temozolomida/farmacología
16.
Biom J ; 55(6): 925-43, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24022794

RESUMEN

Unit nonresponse is often a problem in sample surveys. It arises when the values of the survey variable cannot be recorded for some sampled units. In this paper, the use of nonresponse calibration weighting to treat nonresponse is considered in a complete design-based framework. Nonresponse is viewed as a fixed characteristic of the units. The approach is suitable in environmental and forest surveys when sampled sites cannot be reached by field crews. Approximate expressions of design-based bias and variance of the calibration estimator are derived and design-based consistency is investigated. Choice of auxiliary variables to perform calibration is discussed. Sen-Yates-Grundy, Horvitz-Thompson, and jackknife estimators of the sampling variance are proposed. Analytical and Monte Carlo results demonstrate the validity of the procedure when the relationship between survey and auxiliary variables is similar in respondent and nonrespondent strata. An application to a forest survey performed in Northeastern Italy is considered.


Asunto(s)
Recolección de Datos , Ambiente , Estadística como Asunto/métodos , Análisis de Varianza , Calibración , Conservación de los Recursos Naturales , Análisis de Regresión , Árboles
17.
Sci Total Environ ; 871: 161789, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36716887

RESUMEN

The potential for climate change to affect animal behaviour is widely recognized, yet its possible consequences on aggressiveness are still unclear. If warming and drought limit the availability of food resources, climate change may elicit an increase of intraspecific conflicts stemming from resource competition. By measuring aggressivity indices in a group-living, herbivorous mammal (the Apennine chamois Rupicapra pyrenaica ornata) in two sites differing in habitat quality, and coupling them with estimates of plant productivity, we investigated whether harsh climatic conditions accumulated during the growing season influenced agonistic contests at feeding via vegetation-mediated effects, and their interaction with the site-specific habitat quality. We focused on females, which exhibit intra-group contest competition to access nutritious food patches. Accounting for confounding variables, we found that (1) the aggression rate between foraging individuals increased with the warming accumulated over previous weeks; (2) the probability to deliver more aggressive behaviour patterns toward contestants increased with decreasing rainfall recorded in previous weeks; (3) the effects of cumulative warming and drought on aggressivity indices occurred at time windows spanning 15-30 days, matching those found on vegetation productivity; (4) the effects of unfavourable climatic conditions via vegetation growth on aggressivity were independent of the site-specific habitat quality. Simulations conducted on our model species predict a ~50 % increase in aggression rate following the warming projected over the next 60 years. Where primary productivity will be impacted by warming and drought, our findings suggest that the anticipated climate change scenarios may trigger bottom-up consequences on intraspecific animal conflicts. This study opens the doors for a better understanding of the multifactorial origin of aggression in group-living foragers, emphasising how the escalation of agonistic contests could emerge as a novel response of animal societies to ongoing global warming.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Femenino , Calentamiento Global , Herbivoria , Plantas , Mamíferos
18.
Sci Rep ; 12(1): 15537, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109545

RESUMEN

In previous studies, beta-k distribution and distribution functions strongly related to that, have played important roles in representing extreme events. Among these distributions, the Beta-Singh-Maddala turned out to be adequate for modelling hydrological extreme events. Starting from this distribution, the aim of the paper is to express the model as a function of indexes of hydrological interest and simultaneously investigate on their dependence with a set of explanatory variables in such a way to explore on possible determinants of extreme hydrologic events. Finally, an application to a real hydrologic dataset is considered in order to show the potentiality of the proposed model in describing data and in understanding effects of covariates on frequently adopted hydrological indicators.


Asunto(s)
Hidrología
19.
Cells ; 11(7)2022 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-35406690

RESUMEN

BACKGROUND: Glioblastoma (GB) is a devastating primary brain malignancy. The recurrence of GB is inevitable despite the standard treatment of surgery, chemotherapy, and radiation, and the median survival is limited to around 15 months. The barriers to treatment include the complex interactions among the different cellular components inhabiting the tumor microenvironment. The complex heterogeneous nature of GB cells is helped by the local inflammatory tumor microenvironment, which mostly induces tumor aggressiveness and drug resistance. METHODS: By using fluorescent multiple labeling and a DEPArray cell separator, we recovered several single cells or groups of single cells from populations of different origins from IDH-WT GB samples. From each GB sample, we collected astrocytes-like (GFAP+), microglia-like (IBA1+), stem-like cells (CD133+), and endothelial-like cells (CD105+) and performed Copy Number Aberration (CNA) analysis with a low sequencing depth. The same tumors were subjected to a bulk CNA analysis. RESULTS: The tumor partition in its single components allowed single-cell molecular subtyping which revealed new aspects of the GB altered genetic background. CONCLUSIONS: Nowadays, single-cell approaches are leading to a new understanding of GB physiology and disease. Moreover, single-cell CNAs resource will permit new insights into genome heterogeneity, mutational processes, and clonal evolution in malignant tissues.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/genética , Antecedentes Genéticos , Glioblastoma/patología , Humanos , Microglía/patología , Microambiente Tumoral/genética
20.
Front Oncol ; 12: 969812, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36132155

RESUMEN

Background: Glioblastoma (GB) is the most severe form of brain cancer, with a 12-15 month median survival. Surgical resection, temozolomide (TMZ) treatment, and radiotherapy remain the primary therapeutic options for GB, and no new therapies have been introduced in recent years. This therapeutic standstill is primarily due to preclinical approaches that do not fully respect the complexity of GB cell biology and fail to test efficiently anti-cancer treatments. Therefore, better treatment screening approaches are needed. In this study, we have developed a novel functional precision medicine approach to test the response to anticancer treatments in organoids derived from the resected tumors of glioblastoma patients. Methods: GB organoids were grown for a short period of time to prevent any genetic and morphological evolution and divergence from the tumor of origin. We chose metabolic imaging by NAD(P)H fluorescence lifetime imaging microscopy (FLIM) to predict early and non-invasively ex-vivo anti-cancer treatment responses of GB organoids. TMZ was used as the benchmark drug to validate the approach. Whole-transcriptome and whole-exome analyses were performed to characterize tumor cases stratification. Results: Our functional precision medicine approach was completed within one week after surgery and two groups of TMZ Responder and Non-Responder tumors were identified. FLIM-based metabolic tumor stratification was well reflected at the molecular level, confirming the validity of our approach, highlighting also new target genes associated with TMZ treatment and identifying a new 17-gene molecular signature associated with survival. The number of MGMT gene promoter methylated tumors was higher in the responsive group, as expected, however, some non-methylated tumor cases turned out to be nevertheless responsive to TMZ, suggesting that our procedure could be synergistic with the classical MGMT methylation biomarker. Conclusions: For the first time, FLIM-based metabolic imaging was used on live glioblastoma organoids. Unlike other approaches, ex-vivo patient-tailored drug response is performed at an early stage of tumor culturing with no animal involvement and with minimal tampering with the original tumor cytoarchitecture. This functional precision medicine approach can be exploited in a range of clinical and laboratory settings to improve the clinical management of GB patients and implemented on other cancers as well.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA