230 results on '"Gallego O"'
Search Results
102. Erratum to: Efficacy of erlotinib in patients with relapsed gliobastoma multiforme who expressed EGFRVIII and PTEN determined by immunohistochemistry
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Gallego O, Cuatrecasas M, Benavides M, Pp, Segura, Berrocal A, Erill N, Colomer A, Mj, Quintana, Balaña C, Gil M, Alberto Gallardo, Murata P, and Barnadas A
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Cancer Research ,Neurology ,Oncology ,Neurology (clinical) ,Erratum
103. High rate of resistance to antiretroviral drugs among HIV-infected prison inmates
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Gallego, O., Corral, A., Mendoza, C., González-Lahoz, J., and Vicente Soriano
104. Duodenal Obstruction Secondary to a Metastasis from an Adenocarcinoma of the Cecum: A Case Report.
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Sebastián, J. J., Zaragozano, R., Vicente, J., Gallego, O., and Trufero, J. M.
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METASTASIS ,DUODENAL diseases ,CECUM cancer ,TUMOR surgery ,PALLIATIVE treatment of cancer - Abstract
Metastatic tumors to the gastrointestinal tract are rare; the stomach and small bowel are the most common organs involved. Lung cancer, renal cell carcinoma, breast carcinoma, and malignant melanoma are the most common primary tumors metastatic to the duodenum. We report a metastasis to the duodenum from an adenocarcinoma of the cecum presenting as a duodenal obstruction 4.5 yr after the surgical resection of the primary tumor. The condition of the patient was temporarily controlled with the implantation of an endoduodenal metallic prosthesis as a palliative measure. [ABSTRACT FROM AUTHOR]
- Published
- 1997
105. The exocyst in context.
- Author
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Meek S, Hernandez AC, Oliva B, and Gallego O
- Abstract
The exocyst is a hetero-octameric complex involved in the exocytosis arm of cellular trafficking. Specifically, it tethers secretory vesicles to the plasma membrane, but it is also a main convergence point for many players of exocytosis: regulatory proteins, motor proteins, lipids and Soluble N-ethylmaleimide-sensitive factor Attachment Protein Receptor (SNARE) proteins are all connected physically by the exocyst. Despite extensive knowledge about its structure and interactions, the exocyst remains an enigma precisely because of its increasingly broad and flexible role across the exocytosis process. To solve the molecular mechanism of such a multi-tasking complex, dynamical structures with self, other proteins, and environment should be described. And to do this, interrogation within contexts increasingly close to native conditions is needed. Here we provide a perspective on how different experimental contexts have been used to study the exocyst, and those that could be used in the future. This review describes the structural breakthroughs on the isolated in vitro exocyst, followed by the use of membrane reconstitution assays for revealing in vitro exocyst functionality. Next, it moves to in situ cell contexts, reviewing imaging techniques that have been, and that ideally could be, used to look for near-native structure and organization dynamics. Finally, it looks at the exocyst structure in situ within evolutionary contexts, and the potential of structure prediction therein. From in vitro, to in situ, cross-context investigation of exocyst structure has begun, and will be critical for functional mechanism elucidation., (© 2024 The Author(s).)
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- 2024
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106. PyF2F: a robust and simplified fluorophore-to-fluorophore distance measurement tool for Protein interactions from Imaging Complexes after Translocation experiments.
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Hernandez AC, Ortiz S, Betancur LI, Dojčilović R, Picco A, Kaksonen M, Oliva B, and Gallego O
- Abstract
Structural knowledge of protein assemblies in their physiological environment is paramount to understand cellular functions at the molecular level. Protein interactions from Imaging Complexes after Translocation (PICT) is a live-cell imaging technique for the structural characterization of macromolecular assemblies in living cells. PICT relies on the measurement of the separation between labelled molecules using fluorescence microscopy and cell engineering. Unfortunately, the required computational tools to extract molecular distances involve a variety of sophisticated software programs that challenge reproducibility and limit their implementation to highly specialized researchers. Here we introduce PyF2F, a Python-based software that provides a workflow for measuring molecular distances from PICT data, with minimal user programming expertise. We used a published dataset to validate PyF2F's performance., (© The Author(s) 2024. Published by Oxford University Press on behalf of NAR Genomics and Bioinformatics.)
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- 2024
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107. TRAPPIII requires Drs2 binding to transport Atg9 vesicles at cold temperatures.
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Puig-Tintó M, Pazos I, Betancur L, Hernández AC, and Gallego O
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- Autophagy, Autophagy-Related Proteins metabolism, Cold Temperature, Protein Transport, Transport Vesicles metabolism, Saccharomyces cerevisiae Proteins metabolism, Vesicular Transport Proteins metabolism
- Abstract
Abbreviations: Autophagy-related 9 (Atg9); cytoplasm-to-vacuole targeting (Cvt); Golgi-associated retrograde protein (GARP); multisubunit tethering complexes (MTCs); phagophore assembly site (PAS); phosphatidylserine (PS); Protein interactions from Imaging Complexes after Translocation (PICT); transport protein particle III (TRAPPIII); type IV P-type ATPases (P4-ATPases).
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- 2023
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108. CM2D3: Furnishing the Human Interactome with Structural Models of Protein Complexes Derived by Comparative Modeling and Docking.
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Mirela Bota P, Hernandez AC, Segura J, Gallego O, Oliva B, and Fernandez-Fuentes N
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- Humans, Computational Biology methods, Molecular Docking Simulation, Protein Binding, Protein Conformation, Protein Interaction Mapping methods, Software, Databases, Protein, Proteins chemistry
- Abstract
The human interactome is composed of around half a million interactions according to recent estimations and it is only for a small fraction of those that three-dimensional structural information is available. Indeed, the structural coverage of the human interactome is very low and given the complexity and time-consuming requirements of solving protein structures this problem will remain for the foreseeable future. Structural models, or predictions, of protein complexes can provide valuable information when the experimentally determined 3D structures are not available. Here we present CM2D3, a relational database containing structural models of the whole human interactome derived both from comparative modeling and data-driven docking. Starting from a consensus interactome derived from integrating several interactomics databases, a strategy was devised to derive structural models by computational means. Currently, CM2D3 includes 33338 structural models of which 5121 derived from comparative modeling and the remaining from docking. Of the latter, the structures of 14554 complexes were derived from monomers modeled by M4T while the rest were modeled with structures as predicted by AlphaFold2. Lastly, CM2D3 complements existing resources by focusing on models derived from both free-docking, as opposed to template-based docking, and hence expanding the available structural information on protein complexes to the scientific community. Database URL:http://www.bioinsilico.org/CM2D3., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
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- 2023
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109. The P4-ATPase Drs2 interacts with and stabilizes the multisubunit tethering complex TRAPPIII in yeast.
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Pazos I, Puig-Tintó M, Betancur L, Cordero J, Jiménez-Menéndez N, Abella M, Hernández AC, Duran AG, Adachi-Fernández E, Belmonte-Mateos C, Sabido-Bozo S, Tosi S, Nezu A, Oliva B, Colombelli J, Graham TR, Yoshimori T, Muñiz M, Hamasaki M, and Gallego O
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- Adenosine Triphosphatases genetics, Adenosine Triphosphatases metabolism, Autophagy-Related Proteins genetics, Autophagy-Related Proteins metabolism, Membrane Proteins genetics, Membrane Proteins metabolism, Calcium-Transporting ATPases chemistry, Calcium-Transporting ATPases metabolism, ATP-Binding Cassette Transporters metabolism, Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae metabolism, Saccharomyces cerevisiae Proteins metabolism
- Abstract
Multisubunit Tethering Complexes (MTCs) are a set of conserved protein complexes that tether vesicles at the acceptor membrane. Interactions with other components of the trafficking machinery regulate MTCs through mechanisms that are partially understood. Here, we systematically investigate the interactome that regulates MTCs. We report that P4-ATPases, a family of lipid flippases, interact with MTCs that participate in the anterograde and retrograde transport at the Golgi, such as TRAPPIII. We use the P4-ATPase Drs2 as a paradigm to investigate the mechanism and biological relevance of this interplay during transport of Atg9 vesicles. Binding of Trs85, the sole-specific subunit of TRAPPIII, to the N-terminal tail of Drs2 stabilizes TRAPPIII on membranes loaded with Atg9 and is required for Atg9 delivery during selective autophagy, a role that is independent of P4-ATPase canonical functions. This mechanism requires a conserved I(S/R)TTK motif that also mediates the interaction of the P4-ATPases Dnf1 and Dnf2 with MTCs, suggesting a broader role of P4-ATPases in MTC regulation., (© 2023 The Authors. Published under the terms of the CC BY NC ND 4.0 license.)
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- 2023
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110. Gal-1 Expression Analysis in the GLIOCAT Multicenter Study: Role as a Prognostic Factor and an Immune-Suppressive Biomarker.
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Martínez-Bosch N, Vilariño N, Alameda F, Mojal S, Arumí-Uria M, Carrato C, Aldecoa I, Ribalta T, Vidal N, Bellosillo B, Menéndez S, Del Barco S, Gallego O, Pineda E, López-Martos R, Hernández A, Mesia C, Esteve-Codina A, de la Iglesia N, Balañá C, Martínez-García M, and Navarro P
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- Humans, Galectin 1 genetics, Galectin 1 metabolism, Prognosis, Biomarkers, 14-3-3 Proteins metabolism, Glioblastoma diagnosis, Glioblastoma genetics, Glioblastoma metabolism, Astrocytoma metabolism, Vacuolar Proton-Translocating ATPases metabolism
- Abstract
Glioblastoma (GBM) is the most frequent primary malignant brain tumor and has a dismal prognosis. Unfortunately, despite the recent revolution of immune checkpoint inhibitors in many solid tumors, these have not shown a benefit in overall survival in GBM patients. Therefore, new potential treatment targets as well as diagnostic, prognostic, and/or predictive biomarkers are needed to improve outcomes in this population. The β-galactoside binding protein Galectin-1 (Gal-1) is a protein with a wide range of pro-tumor functions such as proliferation, invasion, angiogenesis, and immune suppression. Here, we evaluated Gal-1 expression by immunohistochemistry in a homogenously treated cohort of GBM (the GLIOCAT project) and correlated its expression with clinical and molecular data. We observed that Gal-1 is a negative prognostic factor in GBM. Interestingly, we observed higher levels of Gal-1 expression in the mesenchymal/classical subtypes compared to the less aggressive proneural subtype. We also observed a Gal-1 expression correlation with immune suppressive signatures of CD4 T-cells and macrophages, as well as with several GBM established biomarkers, including SHC1, PD-L1, PAX2, MEOX2, YKL-40, TCIRG1, YWHAG, OLIG2, SOX2, Ki-67, and SOX11. Moreover, Gal-1 levels were significantly lower in grade 4 IDH-1 mutant astrocytomas, which have a better prognosis. Our results confirm the role of Gal-1 as a prognostic factor and also suggest its value as an immune-suppressive biomarker in GBM.
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- 2023
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111. In silico validation of RNA-Seq results can identify gene fusions with oncogenic potential in glioblastoma.
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Hernandez A, Muñoz-Mármol AM, Esteve-Codina A, Alameda F, Carrato C, Pineda E, Arpí-Lluciá O, Martinez-García M, Mallo M, Gut M, Del Barco S, Gallego O, Dabad M, Mesia C, Bellosillo B, Domenech M, Vidal N, Aldecoa I, de la Iglesia N, and Balana C
- Subjects
- Carcinogenesis, Gene Fusion, Humans, Microtubule-Associated Proteins genetics, Oncogene Proteins, Fusion genetics, RNA-Seq, Glioblastoma pathology, Glioma genetics
- Abstract
RNA-Sequencing (RNA-Seq) can identify gene fusions in tumors, but not all these fusions have functional consequences. Using multiple data bases, we have performed an in silico analysis of fusions detected by RNA-Seq in tumor samples from 139 newly diagnosed glioblastoma patients to identify in-frame fusions with predictable oncogenic potential. Among 61 samples with fusions, there were 103 different fusions, involving 167 different genes, including 20 known oncogenes or tumor suppressor genes (TSGs), 16 associated with cancer but not oncogenes or TSGs, and 32 not associated with cancer but previously shown to be involved in fusions in gliomas. After selecting in-frame fusions able to produce a protein product and running Oncofuse, we identified 30 fusions with predictable oncogenic potential and classified them into four non-overlapping categories: six previously described in cancer; six involving an oncogene or TSG; four predicted by Oncofuse to have oncogenic potential; and 14 other in-frame fusions. Only 24 patients harbored one or more of these 30 fusions, and only two fusions were present in more than one patient: FGFR3::TACC3 and EGFR::SEPTIN14. This in silico study provides a good starting point for the identification of gene fusions with functional consequences in the pathogenesis or treatment of glioblastoma., (© 2022. The Author(s).)
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- 2022
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112. RNA sequencing and Immunohistochemistry Reveal ZFN7 as a Stronger Marker of Survival than Molecular Subtypes in G-CIMP-negative Glioblastoma.
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Esteve-Codina A, Alameda F, Carrato C, Pineda E, Arpí O, Martinez-García M, Mallo M, Gut M, Dabad M, Tortosa A, Del Barco S, Capellades J, Puig J, Gallego O, Pujol T, Oleaga L, Gil-Gil M, de Quintana-Schmidt C, Valduvieco I, Martinez-Cardús A, Bellosillo B, Muñoz-Marmol AM, Esteve A, Domenech M, Camins A, Craven-Bartle J, Villa S, Marruecos J, Domenech S, de la Iglesia N, and Balana C
- Subjects
- Aged, Biomarkers, Tumor metabolism, Brain Neoplasms metabolism, Brain Neoplasms therapy, CpG Islands genetics, DNA Methylation, Female, Gene Expression Profiling methods, Gene Expression Regulation, Neoplastic, Glioblastoma metabolism, Glioblastoma therapy, Humans, Kruppel-Like Transcription Factors metabolism, Male, Middle Aged, Multivariate Analysis, Prognosis, Survival Analysis, Biomarkers, Tumor genetics, Brain Neoplasms genetics, Glioblastoma genetics, Immunohistochemistry methods, Kruppel-Like Transcription Factors genetics, Sequence Analysis, RNA methods
- Abstract
Purpose: Glioblastoma is the most aggressive brain tumor in adults and has few therapeutic options. The study of molecular subtype classifications may lead to improved prognostic classification and identification of new therapeutic targets. The Cancer Genome Atlas (TCGA) subtype classification has mainly been applied in U.S. clinical trials, while the intrinsic glioma subtype (IGS) has mainly been applied in European trials., Experimental Design: From paraffin-embedded tumor samples of 432 patients with uniformly treated, newly diagnosed glioblastoma, we built tissue microarrays for IHC analysis and applied RNA sequencing to the best samples to classify them according to TCGA and IGS subtypes., Results: We obtained transcriptomic results from 124 patients. There was a lack of agreement among the three TCGA classificatory algorithms employed, which was not solely attributable to intratumoral heterogeneity. There was overlapping of TCGA mesenchymal subtype with IGS cluster 23 and of TCGA classical subtype with IGS cluster 18. Molecular subtypes were not associated with prognosis, but levels of expression of 13 novel genes were identified as independent prognostic markers in glioma-CpG island methylator phenotype-negative patients, independently of clinical factors and MGMT methylation. These findings were validated in at least one external database. Three of the 13 genes were selected for IHC validation. In particular, high ZNF7 RNA expression and low ZNF7 protein expression were strongly associated with longer survival, independently of molecular subtypes., Conclusions: TCGA and IGS molecular classifications of glioblastoma have no higher prognostic value than individual genes and should be refined before being applied to clinical trials., (©2020 American Association for Cancer Research.)
- Published
- 2021
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113. A phase II randomized, multicenter, open-label trial of continuing adjuvant temozolomide beyond 6 cycles in patients with glioblastoma (GEINO 14-01).
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Balana C, Vaz MA, Manuel Sepúlveda J, Mesia C, Del Barco S, Pineda E, Muñoz-Langa J, Estival A, de Las Peñas R, Fuster J, Gironés R, Navarro LM, Gil-Gil M, Alonso M, Herrero A, Peralta S, Olier C, Perez-Segura P, Covela M, Martinez-García M, Berrocal A, Gallego O, Luque R, Perez-Martín FJ, Esteve A, Munne N, Domenech M, Villa S, Sanz C, and Carrato C
- Subjects
- Antineoplastic Agents, Alkylating adverse effects, Antineoplastic Agents, Alkylating therapeutic use, Disease-Free Survival, Humans, Temozolomide adverse effects, Temozolomide therapeutic use, Brain Neoplasms drug therapy, Glioblastoma drug therapy
- Abstract
Background: Standard treatment for glioblastoma is radiation with concomitant and adjuvant temozolomide for 6 cycles, although the optimal number of cycles of adjuvant temozolomide has long been a subject of debate. We performed a phase II randomized trial investigating whether extending adjuvant temozolomide for more than 6 cycles improved outcome., Methods: Glioblastoma patients treated at 20 Spanish hospitals who had not progressed after 6 cycles of adjuvant temozolomide were centrally randomized to stop (control arm) or continue (experimental arm) temozolomide up to a total of 12 cycles at the same doses they were receiving in cycle 6. Patients were stratified by MGMT methylation and measurable disease. The primary endpoint was differences in 6-month progression-free survival (PFS). Secondary endpoints were PFS, overall survival (OS), and safety (Clinicaltrials.gov NCT02209948)., Results: From August 2014 to November 2018, 166 patients were screened, 7 of whom were ineligible. Seventy-nine patients were included in the stop arm and 80 in the experimental arm. All patients were included in the analyses of outcomes and of safety. There were no differences in 6-month PFS (control 55.7%; experimental 61.3%), PFS, or OS between arms. MGMT methylation and absence of measurable disease were independent factors of better outcome. Patients in the experimental arm had more lymphopenia (P < 0.001), thrombocytopenia (P < 0.001), and nausea and vomiting (P = 0.001)., Conclusions: Continuing temozolomide after 6 adjuvant cycles is associated with greater toxicity but confers no additional benefit in 6-month PFS., Key Points: 1. Extending adjuvant temozolomide to 12 cycles did not improve 6-month PFS.2. Extending adjuvant temozolomide did not improve PFS or OS in any patient subset.3. Extending adjuvant temozolomide was linked to increased toxicities., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2020
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114. Glioblastoma TCGA Mesenchymal and IGS 23 Tumors are Identifiable by IHC and have an Immune-phenotype Indicating a Potential Benefit from Immunotherapy.
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Carrato C, Alameda F, Esteve-Codina A, Pineda E, Arpí O, Martinez-García M, Mallo M, Gut M, Lopez-Martos R, Barco SD, Ribalta T, Capellades J, Puig J, Gallego O, Mesia C, Muñoz-Marmol AM, Archilla I, Arumí M, Blanc JM, Bellosillo B, Menendez S, Esteve A, Bagué S, Hernandez A, Craven-Bartle J, Fuentes R, Vidal N, Aldecoa I, Iglesia N, and Balana C
- Subjects
- Brain Neoplasms genetics, Brain Neoplasms immunology, Brain Neoplasms pathology, Computational Biology, Follow-Up Studies, Glioblastoma genetics, Glioblastoma immunology, Glioblastoma pathology, Humans, Prognosis, RNA-Seq, Retrospective Studies, Tissue Array Analysis, Biomarkers, Tumor genetics, Brain Neoplasms classification, Glioblastoma classification, Immunohistochemistry methods, Immunophenotyping methods, Mesoderm pathology, Oncogene Proteins, Fusion genetics
- Abstract
Purpose: Molecular subtype classifications in glioblastoma may detect therapy sensitivities. IHC would potentially allow the identification of molecular subtypes in routine clinical practice., Experimental Design: Formalin-fixed, paraffin-embedded tumor samples of 124 uniformly treated, newly diagnosed patients with glioblastoma were submitted to RNA sequencing, IHC, and immune-phenotyping to identify differences in molecular subtypes associated with treatment sensitivities., Results: We detected high molecular and IHC overlapping of the The Cancer Genome Atlas (TCGA) mesenchymal subtype with instrinsic glioma subtypes (IGS) cluster 23 and of the TCGA classical subtype with IGS cluster 18. IHC patterns, gene fusion profiles, and immune-phenotypes varied across subtypes. IHC revealed that the TCGA classical subtype was identified by high expression of EGFR and low expression of PTEN, while the mesenchymal subtype was identified by low expression of SOX2 and high expression of two antibodies, SHC1 and TCIRG1, selected on the basis of RNA differential transcriptomic expression. The proneural subtype was identified by frequent positive IDH1 expression and high Olig2 and Ki67 expression. Immune-phenotyping showed that mesenchymal and IGS 23 tumors exhibited a higher positive effector cell score, a higher negative suppressor cell score, and lower levels of immune checkpoint molecules. The cell-type deconvolution analysis revealed that these tumors are highly enriched in M2 macrophages, resting memory CD4
+ T cells, and activated dendritic cells, indicating that they may be ideal candidates for immunotherapy, especially with anti-M2 and/or dendritic cell vaccination., Conclusions: There is a subset of tumors, frequently classified as mesenchymal or IGS cluster 23, that may be identified with IHC and could well be optimal candidates for immunotherapy., (©2020 American Association for Cancer Research.)- Published
- 2020
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115. Live-Cell Structural Biology to Solve Biological Mechanisms: The Case of the Exocyst.
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Irastorza-Azcarate I, Castaño-Díez D, Devos DP, and Gallego O
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- Cell Membrane metabolism, Cytoplasm metabolism, Models, Molecular, Protein Conformation, Protein Multimerization, Protein Transport, Proteins metabolism, Cell Membrane ultrastructure, Cryoelectron Microscopy methods, Cytoplasm ultrastructure, Electron Microscope Tomography methods, Exocytosis, Proteins chemistry
- Abstract
Historically, structural biology has been largely centered on in vitro approaches as the dominant technique to obtain indispensable high-resolution data. In situ structural biology is now poised to contribute with high-precision observations in a near-physiological context. Mass spectrometry, electron tomography, and fluorescence microscopy are opening up new opportunities for structural analysis, including the study of the protein machinery in living cells. The complementarity between studies is increasingly used to reveal biologically significant observations. Here we compare two complementary studies addressing the mechanisms of vesicle tethering with in vitro and in situ approaches. Cryoelectron microscopy and live-cell imaging assisted by anchoring platforms team up to explore elusive mechanisms of exocytosis, showing directions of future research., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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116. Pseudoprogression as an adverse event of glioblastoma therapy.
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Balaña C, Capellades J, Pineda E, Estival A, Puig J, Domenech S, Verger E, Pujol T, Martinez-García M, Oleaga L, Velarde J, Mesia C, Fuentes R, Marruecos J, Del Barco S, Villà S, Carrato C, Gallego O, Gil-Gil M, Craven-Bartle J, and Alameda F
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers, Tumor genetics, Brain Neoplasms diagnostic imaging, Brain Neoplasms genetics, Brain Neoplasms mortality, Chi-Square Distribution, DNA Methylation, DNA Modification Methylases genetics, DNA Repair Enzymes genetics, Disease Progression, Disease-Free Survival, Female, Glioblastoma diagnostic imaging, Glioblastoma genetics, Glioblastoma mortality, Humans, Kaplan-Meier Estimate, Magnetic Resonance Imaging, Male, Middle Aged, Odds Ratio, Polymerase Chain Reaction, Predictive Value of Tests, Proportional Hazards Models, Retrospective Studies, Risk Factors, Spain, Time Factors, Treatment Outcome, Tumor Suppressor Proteins genetics, Young Adult, Brain Neoplasms therapy, Glioblastoma therapy
- Abstract
We explored predictive factors of pseudoprogression (PsP) and its impact on prognosis in a retrospective series of uniformly treated glioblastoma patients. Patients were classified as having PsP, early progression (eP) or neither (nP). We examined potential associations with clinical, molecular, and basal imaging characteristics and compared overall survival (OS), progression-free survival (PFS), post-progression survival (PPS) as well as the relationship between PFS and PPS in the three groups. Of the 256 patients studied, 56 (21.9%) were classified as PsP, 70 (27.3%) as eP, and 130 (50.8%) as nP. Only MGMT methylation status was associated to PsP. MGMT methylated patients had a 3.5-fold greater possibility of having PsP than eP (OR: 3.48; 95% CI: 1.606-7.564; P = 0.002). OS was longer for PsP than eP patients (18.9 vs. 12.3 months; P = 0.0001) but was similar for PsP and nP patients (P = 0.91). OS was shorter-though not significantly so-for PsP than nP patients (OS: 19.5 vs. 27.9 months; P = 0.63) in methylated patients. PPS was similar for patients having PsP, eP or nP (PPS: 7.2 vs. 5.4 vs. 6.7; P = 0.43). Neurological deterioration occurred in 64.3% of cases at the time they were classified as PsP and in 72.8% of cases of eP (P = 0.14). PsP confounds the evaluation of disease and does not confer a survival advantage in glioblastoma., (© 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)
- Published
- 2017
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117. The dynamic assembly of distinct RNA polymerase I complexes modulates rDNA transcription.
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Torreira E, Louro JA, Pazos I, González-Polo N, Gil-Carton D, Duran AG, Tosi S, Gallego O, Calvo O, and Fernández-Tornero C
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- Cryoelectron Microscopy, DNA Mutational Analysis, Protein Binding, Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae metabolism, DNA, Ribosomal genetics, Pol1 Transcription Initiation Complex Proteins metabolism, Protein Multimerization, RNA Polymerase I metabolism, Saccharomyces cerevisiae enzymology, Saccharomyces cerevisiae Proteins metabolism, Transcription, Genetic
- Abstract
Cell growth requires synthesis of ribosomal RNA by RNA polymerase I (Pol I). Binding of initiation factor Rrn3 activates Pol I, fostering recruitment to ribosomal DNA promoters. This fundamental process must be precisely regulated to satisfy cell needs at any time. We present in vivo evidence that, when growth is arrested by nutrient deprivation, cells induce rapid clearance of Pol I-Rrn3 complexes, followed by the assembly of inactive Pol I homodimers. This dual repressive mechanism reverts upon nutrient addition, thus restoring cell growth. Moreover, Pol I dimers also form after inhibition of either ribosome biogenesis or protein synthesis. Our mutational analysis, based on the electron cryomicroscopy structures of monomeric Pol I alone and in complex with Rrn3, underscores the central role of subunits A43 and A14 in the regulation of differential Pol I complexes assembly and subsequent promoter association.
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- 2017
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118. The In Vivo Architecture of the Exocyst Provides Structural Basis for Exocytosis.
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Picco A, Irastorza-Azcarate I, Specht T, Böke D, Pazos I, Rivier-Cordey AS, Devos DP, Kaksonen M, and Gallego O
- Subjects
- Golgi Apparatus metabolism, Models, Molecular, Secretory Vesicles metabolism, Exocytosis, Saccharomyces cerevisiae cytology, Saccharomyces cerevisiae metabolism
- Abstract
The structural characterization of protein complexes in their native environment is challenging but crucial for understanding the mechanisms that mediate cellular processes. We developed an integrative approach to reconstruct the 3D architecture of protein complexes in vivo. We applied this approach to the exocyst, a hetero-octameric complex of unknown structure that is thought to tether secretory vesicles during exocytosis with a poorly understood mechanism. We engineered yeast cells to anchor the exocyst on defined landmarks and determined the position of its subunit termini at nanometer precision using fluorescence microscopy. We then integrated these positions with the structural properties of the subunits to reconstruct the exocyst together with a vesicle bound to it. The exocyst has an open hand conformation made of rod-shaped subunits that are interlaced in the core. The exocyst architecture explains how the complex can tether secretory vesicles, placing them in direct contact with the plasma membrane., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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119. Bevacizumab and temozolomide versus temozolomide alone as neoadjuvant treatment in unresected glioblastoma: the GENOM 009 randomized phase II trial.
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Balana C, De Las Penas R, Sepúlveda JM, Gil-Gil MJ, Luque R, Gallego O, Carrato C, Sanz C, Reynes G, Herrero A, Ramirez JL, Pérez-Segura P, Berrocal A, Vieitez JM, Garcia A, Vazquez-Estevez S, Peralta S, Fernandez I, Henriquez I, Martinez-Garcia M, De la Cruz JJ, Capellades J, Giner P, and Villà S
- Subjects
- Adult, Aged, Bevacizumab administration & dosage, Brain Neoplasms pathology, Dacarbazine administration & dosage, Dacarbazine analogs & derivatives, Female, Follow-Up Studies, Glioblastoma pathology, Humans, Male, Middle Aged, Neoplasm Staging, Prognosis, Survival Rate, Temozolomide, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Brain Neoplasms drug therapy, Glioblastoma drug therapy, Neoadjuvant Therapy
- Abstract
We sought to determine the impact of bevacizumab on reduction of tumor size prior to chemoradiotherapy in unresected glioblastoma patients. Patients were randomized 1:1 to receive temozolomide (TMZ arm) or temozolomide plus bevacizumab (TMZ + BEV arm). In both arms, neoadjuvant treatment was temozolomide (85 mg/m(2), days 1-21, two 28-day cycles), concurrent radiation plus temozolomide, and six cycles of adjuvant temozolomide. In the TMZ + BEV arm, bevacizumab (10 mg/kg) was added on days 1 and 15 of each neoadjuvant cycle and on days 1, 15 and 30 of concurrent treatment. The primary endpoint was investigator-assessed response to neoadjuvant treatment. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and the impact on outcome of MGMT methylation in tumor and serum. One hundred and two patients were included; 43 in the TMZ arm and 44 in the TMZ + BEV arm were evaluable for response. Results favored the TMZ + BEV arm in terms of objective response (3 [6.7 %] vs. 11 [22.9 %]; odds ratio 4.2; P = 0.04). PFS and OS were longer in the TMZ + BEV arm, though the difference did not reach statistical significance. MGMT methylation in tumor, but not in serum, was associated with outcome. More patients experienced toxicities in the TMZ + BEV than in the TMZ arm (P = 0.06). The combination of bevacizumab plus temozolomide is more active than temozolomide alone and may well confer benefit in terms of tumor shrinkage in unresected patients albeit at the expense of greater toxicity.
- Published
- 2016
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120. Phase II trial of irinotecan and metronomic temozolomide in patients with recurrent glioblastoma.
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Reynés G, Martínez-Sales V, Vila V, Balañá C, Pérez-Segura P, Vaz MA, Benavides M, Gallego O, Palomero I, Gil-Gil M, Fleitas T, and Reche E
- Subjects
- Administration, Metronomic, Adult, Aged, Camptothecin administration & dosage, Camptothecin analogs & derivatives, Dacarbazine administration & dosage, Dacarbazine analogs & derivatives, Female, Humans, Irinotecan, Male, Middle Aged, Neoplasm Recurrence, Local, Temozolomide, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Brain Neoplasms drug therapy, Glioblastoma drug therapy
- Abstract
This phase II study was conducted to determine the efficacy and safety of metronomic temozolomide (TMZ) in combination with irinotecan in glioblastoma (GB) at first relapse. Patients with GB at first relapse received TMZ 50 mg/m/2day divided into three doses, except for a single 100 mg/m2 dose, administered between 3 and 6 h before every irinotecan infusion. Irinotecan was given intravenously at the previously established dose of 100 mg/m2 on days 8 and 22 of 28-day cycles. Treatment was given for a maximum of nine cycles or until progression or unacceptable toxicity occurred. Vascular endothelial growth factor and its soluble receptor 1, thrombospondin-1, microparticles, and microparticle-dependent procoagulant activity were measured in blood before treatment. The primary objective was 6-month progression-free survival (PFS). Twenty-seven evaluable patients were enrolled. Six-month PFS was 20.8%. Median PFS was 11.6 weeks (95% confidence interval: 7.5-15.7). Stable disease was the best response for nine (37.5%) patients, with a median duration of 11.2 weeks (4.2-35.85 weeks). No differences in PFS or response were observed among patients who relapsed during or after completion of adjuvant TMZ. Grade 3/4 adverse events included lymphopenia (15%), fatigue, diarrhea and febrile neutropenia (3.7% each), lymphopenia, neutropenia, and nausea/vomiting (11.1% each). One patient died from pneumonia and one patient died from pulmonary thromboembolism. Pretreatment levels of angiogenesis biomarkers, microparticles, and microparticle-related procoagulant activity were elevated in patients compared with healthy volunteers. This regimen is feasible, but failed to improve the results obtained with other second-line therapies in recurrent GB.
- Published
- 2016
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121. A phase I study of irinotecan in combination with metronomic temozolomide in patients with recurrent glioblastoma.
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Reynés G, Balañá C, Gallego O, Iglesias L, Pérez P, and García JL
- Subjects
- Adult, Aged, Camptothecin administration & dosage, Camptothecin analogs & derivatives, Dacarbazine administration & dosage, Dacarbazine analogs & derivatives, Female, Humans, Irinotecan, Male, Maximum Tolerated Dose, Middle Aged, Temozolomide, Administration, Metronomic, Antineoplastic Combined Chemotherapy Protocols adverse effects, Central Nervous System Neoplasms drug therapy, Glioblastoma drug therapy, Neoplasm Recurrence, Local drug therapy
- Abstract
To determine the maximum tolerated dose of irinotecan administered every 2 weeks, in combination with a fixed and continuous administration of temozolomide, in patients with glioblastoma at first relapse. Patients received oral temozolomide at a fixed and continuous dose of 50 mg/m divided into three daily doses, except for a single 100 mg/m dose, administered before every irinotecan infusion. Irinotecan was given intravenously on days 8 and 22 of 28-day cycles. The starting dose of irinotecan was 100 mg/m, and this was escalated by increments of 15 mg/m in cohorts of 3-6 evaluable patients. Determination of the dose-limiting toxicity was based on toxicities recorded from day 1 of the first cycleto day 8 of the third cycle. Enzyme-inducing antiepileptic drugs were not allowed. Tumor response was assessed by MRI every 8 weeks. Twelve patients were enrolled in this phase I study. The three patients enrolled at dose level 1 and six of nine patients enrolled at dose level 2 were evaluable for toxicity. The maximum tolerated dose of irinotecan was 100 mg/m. The dose-limiting toxicities were hematologic and gastrointestinal. Nine patients were evaluable for response: one patient achieved a partial response, four patients remained stable, and four patients had disease progression. The combination of metronomic temozolomide and irinotecan every 2 weeks can be safely administered at the recommended doses; a phase II study with this combination was started and has completed accrual.
- Published
- 2014
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122. [Influence of the combination of antiplatelet agents on the occurrence of early left ventricular insufficiency in patients with acute coronary syndromes without persistent ST-segment elevation].
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Blancas Gómez-Casero R, Quintana Díaz M, Chana García M, Martín Parra C, López Matamala B, Estébanez Montiel B, Ballesteros Ortega D, Martínez González O, Vigil Escribano D, Prieto Valderrey F, Marina Martínez L, and Castro Gallego O
- Subjects
- Acute Coronary Syndrome complications, Aged, Aged, 80 and over, Aspirin adverse effects, Aspirin therapeutic use, Clopidogrel, Drug Therapy, Combination adverse effects, Female, Humans, Male, Middle Aged, Platelet Aggregation Inhibitors therapeutic use, Prospective Studies, Risk Factors, Ticlopidine adverse effects, Ticlopidine analogs & derivatives, Ticlopidine therapeutic use, Tirofiban, Treatment Outcome, Tyrosine adverse effects, Tyrosine analogs & derivatives, Tyrosine therapeutic use, Ventricular Dysfunction, Left epidemiology, Ventricular Dysfunction, Left etiology, Acute Coronary Syndrome drug therapy, Platelet Aggregation Inhibitors adverse effects, Ventricular Dysfunction, Left chemically induced
- Abstract
Background and Objective: The frequency of left ventricular failure (LVF) in the early stages of non-ST-segment elevation acute coronary syndrome (NSTE ACS) has not been described so far. The objective of this study is to describe for the first time the frequency of LVF in the early course of NSTE ACS and to assess its association with other interventions., Patients and Method: Observational prospective cohort multicenter study in intensive and coronary care units (ICCU). Patients with NSTE ACS admitted within 24h after onset were included. Main outcome was the occurrence of LVF. We evaluated the association between LVF and clinical and therapeutic variables., Results: LVF occurred in 15.6% of patients. Coronary angiography (CA) during admission to the ICCU was a protective variable against the main outcome, performed before 72h (odds ratio [OR] 0.47; 95% confidence interval [95% CI] 0.25-0.89; P=.022) and later (OR 0,39; 95% CI 0,15-0,98; P=.044). The administration of beta-blockers was a protective variable against the occurrence of LVF (OR 0,54; 95% CI 0,32-0,87; P=.013). Patients receiving acetylsalicylic acid before admission to the ICCU had a higher risk of developing LVF (OR 1.74; 95% CI 1.06-2.86; P=.028). Age was also a factor of risk for LVF (OR 1.02; 95% CI 1.00-1.05; P=.032)., Conclusions: CA and beta-blockers can decrease the occurrence of LVF. The association between previous administration of acetylsalicylic acid and age with the occurrence of LVF may reflect long-standing cardiovascular disease., (Copyright © 2012 Elsevier España, S.L. All rights reserved.)
- Published
- 2014
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123. [Microwave ablation of a sarcoma lung metastasis in a patient with a pacemaker].
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Hidalgo A, Guerra JM, Gallego O, and Franquet T
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- Aged, Equipment Design, Humans, Male, Ablation Techniques instrumentation, Lung Neoplasms secondary, Lung Neoplasms surgery, Microwaves therapeutic use, Pacemaker, Artificial, Sarcoma secondary, Sarcoma surgery
- Abstract
We present the case of a patient with a pacemaker and a sarcoma lung metastasis treated with microwave ablation. Although the treatment of tumours with microwave ablation is a successful and minimally invasive approach, there are concerns about the safety of this procedure for patients with implanted cardiac devices, such as a pacemaker. After careful planning between radiology and cardiology, microwave ablation was indicated in the patient since it is safer and shorter than the radiofrequency technique. The lesion was treated without complications. It is important to communicate the procedures performed, as well as any complications in order to formulate guidelines for the use of microwave ablation in patients with pacemakers., (Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.)
- Published
- 2014
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124. Efficacy of erlotinib in patients with relapsed gliobastoma multiforme who expressed EGFRVIII and PTEN determined by immunohistochemistry.
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Gallego O, Cuatrecasas M, Benavides M, Segura PP, Berrocal A, Erill N, Colomer A, Quintana MJ, Balaña C, Gil M, Gallardo A, Murata P, and Barnadas A
- Subjects
- Female, Humans, Kaplan-Meier Estimate, Male, Neoplasm Recurrence, Local diagnosis, Neoplasm Recurrence, Local etiology, Radiosurgery methods, Brain Neoplasms therapy, Hemangiopericytoma therapy
- Abstract
Epidermal growth factor receptor gene (EGFR) alteration is a common feature in most of glioblastoma multiforme (GBM). Robust response of anti-EGFR treatments has been mostly associated with the EGFR deletion mutant variant III (EGFRvIII) and expression of PTEN. We have performed a prospective trial in order to confirm the efficacy of erlotinib treatment in patients with relapsed GBM who expressed EGFRvIII and PTEN. All patients included in the trial were required to be PTEN (+++), EGFR (+++) and EGFRvIII (+++) positives by immunohistochemistry. This new phase II trial enrolled 40 patients and was design to be stopped in case of fewer than two responses in the first 13 patients. Patient eligibility included histopathology criteria, radiological progression, more than 18 years old, Karnofsky performed status, KPS > 50, and adequate bone marrow and organ function. There was no limit to the number of prior treatments for relapses. No enzyme-inducing antiepileptic drugs were allowed. The primary endpoints were response and progression-free survival at 6 months (PFS6). Thirteen patients (6 men, 7 women) with recurrent GBM received erlotinib 150 mg/day. Median age was 53 years, median KPS was 80, and median prior treatments for relapses were 2. There was one partial response and three stable diseases (one at 18 months). PFS at 6 months was 20 %. Dose reduction for toxicity was not needed in any patient. Dermatitis was the main treatment-related toxicity, grade 1 in 8 patients and grade 2 in 5 patients. No grade 3 toxicity was observed. Median survival was 7 months (95 % IC 1.41-4.7). As conclusion, monotherapy with erlotinib in GBM relapses patients with high protein expression for PTEN (+++), EGFR (+++), and EGFRvlII (+++) showed low toxicity but minimal efficacy and the trial stopped.
- Published
- 2014
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125. Detection and characterization of protein interactions in vivo by a simple live-cell imaging method.
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Gallego O, Specht T, Brach T, Kumar A, Gavin AC, and Kaksonen M
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- Adaptor Proteins, Signal Transducing metabolism, Carrier Proteins metabolism, Endocytosis, Exocytosis, Fluorescence Recovery After Photobleaching, MAP Kinase Kinase Kinases metabolism, MAP Kinase Signaling System, Microscopy, Fluorescence, Multiprotein Complexes metabolism, Protein Interaction Maps, Protein Multimerization, Protein Transport, Saccharomyces cerevisiae cytology, Saccharomyces cerevisiae Proteins metabolism, Single-Cell Analysis, Vesicular Transport Proteins metabolism, Protein Interaction Mapping methods, Saccharomyces cerevisiae metabolism
- Abstract
Over the last decades there has been an explosion of new methodologies to study protein complexes. However, most of the approaches currently used are based on in vitro assays (e.g. nuclear magnetic resonance, X-ray, electron microscopy, isothermal titration calorimetry etc). The accurate measurement of parameters that define protein complexes in a physiological context has been largely limited due to technical constrains. Here, we present PICT (Protein interactions from Imaging of Complexes after Translocation), a new method that provides a simple fluorescence microscopy readout for the study of protein complexes in living cells. We take advantage of the inducible dimerization of FK506-binding protein (FKBP) and FKBP-rapamycin binding (FRB) domain to translocate protein assemblies to membrane associated anchoring platforms in yeast. In this assay, GFP-tagged prey proteins interacting with the FRB-tagged bait will co-translocate to the FKBP-tagged anchor sites upon addition of rapamycin. The interactions are thus encoded into localization changes and can be detected by fluorescence live-cell imaging under different physiological conditions or upon perturbations. PICT can be automated for high-throughput studies and can be used to quantify dissociation rates of protein complexes in vivo. In this work we have used PICT to analyze protein-protein interactions from three biological pathways in the yeast Saccharomyces cerevisiae: Mitogen-activated protein kinase cascade (Ste5-Ste11-Ste50), exocytosis (exocyst complex) and endocytosis (Ede1-Syp1).
- Published
- 2013
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126. Bevacizumab plus irinotecan in recurrent malignant glioma shows high overall survival in a multicenter retrospective pooled series of the Spanish Neuro-Oncology Research Group (GEINO).
- Author
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Gil MJ, de Las Peñas R, Reynés G, Balañá C, Peréz-Segura P, García-Velasco A, Mesia C, Gallego O, Fernández-Chacón C, Martínez-García M, Herrero A, Andrés R, Benavides M, Quintanar T, and Pérez-Martin X
- Subjects
- Adult, Aged, Antibodies, Monoclonal, Humanized administration & dosage, Bevacizumab, Camptothecin administration & dosage, Camptothecin analogs & derivatives, Central Nervous System Neoplasms pathology, Central Nervous System Neoplasms radiotherapy, Compassionate Use Trials, Dacarbazine analogs & derivatives, Dacarbazine therapeutic use, Disease Progression, Glioma pathology, Glioma radiotherapy, Humans, Irinotecan, Middle Aged, Neoplasm Recurrence, Local drug therapy, Neoplasm Recurrence, Local mortality, Neoplasm Recurrence, Local pathology, Retrospective Studies, Temozolomide, Treatment Outcome, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Central Nervous System Neoplasms drug therapy, Central Nervous System Neoplasms mortality, Glioma drug therapy, Glioma mortality
- Abstract
There is no 'standard of care' for recurrent malignant glioma (MG). Our aim is to confirm the efficacy and safety of bevacizumab 10 mg/kg plus irinotecan 125 mg/m² (or 340 mg/m² if enzyme-inducing antiepileptic drugs) every 2 weeks for a maximum of 1 year in a retrospective pooled series of patients with recurrent MG. The inclusion criteria were as follows: age 18 years and above, histology of MG, progression after radiation and temozolomide, Karnofsky performance status (KPS) of at least 60, and signed informed consent for bevacizumab compassionate use. Response was assessed by MRI using the Macdonald criteria and evaluation of the FLAIR sequence every 8 weeks. A total of 130 patients were enrolled; 72% had glioblastoma (GBM). The median age of the patients was 53 years (20-78); the median KPS was 80%; the median number of prior chemotherapy lines was 2 (1-5); the median interval between the diagnosis of MG and inclusion was 14.6 months (2-166); and the median number of bevacizumab infusions was 8 (1-39). The median follow-up duration was 7.2 months (1-47). The median overall survival (OS) was 8.8 months for GBM and 11.2 months for anaplastic glioma (AG). The median progression-free survival was 5.1 months for GBM and 4.6 months for AG. The response rate was 56% for GBM and 68% for AG. Neurological and KPS improvements were observed in 49 and 45% of patients. Only KPS less than 80% was associated with a worse significant response rate (odds ratio, 0.57; 95% confidence interval, 0.22-0.96). The most frequent grades 3-4 toxicities were asthenia (7%), diarrhea (6%), and thromboembolic events (5%). There were five toxic deaths (4%). Bevacizumab plus irinotecan in recurrent MG improves responses, progression-free survival, and OS compared with historical data. KPS of at least 80% was a predictive factor for response and OS.
- Published
- 2012
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127. Pituitary adenylate cyclase-activating polypeptide counteracts the impaired adult neural stem cell viability induced by palmitate.
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Mansouri S, Ortsäter H, Pintor Gallego O, Darsalia V, Sjöholm A, and Patrone C
- Subjects
- Adenosine Triphosphate metabolism, Analysis of Variance, Animals, Cell Survival drug effects, Cells, Cultured, Corpus Striatum drug effects, Corpus Striatum metabolism, Dose-Response Relationship, Drug, Fatty Acids pharmacology, Gene Expression Regulation drug effects, Lateral Ventricles cytology, Mice, Mice, Inbred C57BL, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-bcl-2, RNA, Messenger metabolism, Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide genetics, Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide metabolism, Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I genetics, Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I metabolism, Receptors, Vasoactive Intestinal Peptide, Type II genetics, Receptors, Vasoactive Intestinal Peptide, Type II metabolism, Receptors, Vasoactive Intestinal Polypeptide, Type I genetics, Receptors, Vasoactive Intestinal Polypeptide, Type I metabolism, Thymidine metabolism, Tritium metabolism, Adult Stem Cells drug effects, Neurotransmitter Agents pharmacology, Palmitates adverse effects, Pituitary Adenylate Cyclase-Activating Polypeptide pharmacology
- Abstract
Diabetes and obesity are characterized by hyperlipidemia and represent risk factors for premature neurological disorders. Diabetic/obese animals have impaired adult neurogenesis. We hypothesize that lipotoxicity leading to neurogenesis impairment plays a role in the development of neurological complications. If so, normalizing neurogenesis in diabetes/obesity could be therapeutically useful in counteracting neurological dysfunction. The goal of this study was to determine the potential of pituitary adenylate cyclase-activating polypeptide (PACAP) to protect adult neural stem cells (NSCs) from lipotoxicity and to study the expression of PACAP receptors in NSCs under lipotoxic conditions in vitro and in the subventricular zone in vivo. The viability of NSCs isolated from the adult mouse brain subventricular zone was assessed in the presence of a high-fat milieu, as mimicked by palmitate, which characterizes diabetic lipotoxicity. Regulation studies of PACAP receptors were performed by quantitative PCR on NSCs in vitro or on subventricular tissues isolated from obese ob/ob mice and their lean littermates. We show that palmitate impairs NSC viability by promoting lipoapoptosis. We also show that PACAP counteracts lipotoxicity via PAC-1 receptor activation. Studies on PACAP receptor expression revealed that PAC-1 and VPAC-2 are expressed by NSC in vitro and are upregulated by palmitate treatment and that PAC-1, VPAC-1, and VPAC-2 are expressed in the subventricular zone/striatum in vivo and are upregulated in ob/ob mice. The present study reveals a previously uncharacterized role of PACAP to protect NSC from lipotoxicity and suggests a potential therapeutic role for PACAP receptor agonists in the treatment of neurological complications in obesity and diabetes., (Copyright © 2011 Wiley Periodicals, Inc.)
- Published
- 2012
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128. Detoxifying antitumoral drugs via nanoconjugation: the case of gold nanoparticles and cisplatin.
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Comenge J, Sotelo C, Romero F, Gallego O, Barnadas A, Parada TG, Domínguez F, and Puntes VF
- Subjects
- Animals, Antineoplastic Agents adverse effects, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Cell Line, Tumor, Cisplatin adverse effects, Cisplatin chemistry, Cisplatin pharmacology, DNA, Neoplasm metabolism, Drug Carriers chemistry, Endocytosis drug effects, Humans, Hydrogen-Ion Concentration drug effects, Inactivation, Metabolic, Metal Nanoparticles toxicity, Metal Nanoparticles ultrastructure, Mice, Organ Size drug effects, Time Factors, Tissue Distribution drug effects, United States, United States Food and Drug Administration, Antineoplastic Agents pharmacokinetics, Cisplatin pharmacokinetics, Gold chemistry, Metal Nanoparticles chemistry, Nanotechnology methods
- Abstract
Nanoparticles (NPs) have emerged as a potential tool to improve cancer treatment. Among the proposed uses in imaging and therapy, their use as a drug delivery scaffold has been extensively highlighted. However, there are still some controversial points which need a deeper understanding before clinical application can occur. Here the use of gold nanoparticles (AuNPs) to detoxify the antitumoral agent cisplatin, linked to a nanoparticle via a pH-sensitive coordination bond for endosomal release, is presented. The NP conjugate design has important effects on pharmacokinetics, conjugate evolution and biodistribution and results in an absence of observed toxicity. Besides, AuNPs present unique opportunities as drug delivery scaffolds due to their size and surface tunability. Here we show that cisplatin-induced toxicity is clearly reduced without affecting the therapeutic benefits in mice models. The NPs not only act as carriers, but also protect the drug from deactivation by plasma proteins until conjugates are internalized in cells and cisplatin is released. Additionally, the possibility to track the drug (Pt) and vehicle (Au) separately as a function of organ and time enables a better understanding of how nanocarriers are processed by the organism.
- Published
- 2012
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129. Retinaldehyde is a substrate for human aldo-keto reductases of the 1C subfamily.
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Ruiz FX, Porté S, Gallego O, Moro A, Ardèvol A, Del Río-Espínola A, Rovira C, Farrés J, and Parés X
- Subjects
- 20-Hydroxysteroid Dehydrogenases chemistry, 3-Hydroxysteroid Dehydrogenases chemistry, 3-Hydroxysteroid Dehydrogenases genetics, Aldo-Keto Reductase Family 1 Member C3, Amino Acid Substitution, Binding Sites, Cell Line, Tumor, Cell Proliferation, Humans, Hydroxyprostaglandin Dehydrogenases chemistry, Hydroxyprostaglandin Dehydrogenases genetics, Hydroxysteroid Dehydrogenases chemistry, Hydroxysteroid Dehydrogenases metabolism, Kinetics, Models, Molecular, Mutagenesis, Site-Directed, Oxidoreductases chemistry, Oxidoreductases metabolism, Protein Binding, Receptors, Retinoic Acid antagonists & inhibitors, Receptors, Retinoic Acid metabolism, Retinaldehyde pharmacology, Retinaldehyde physiology, Substrate Specificity, Transcriptional Activation, Vitamin A chemistry, Vitamin A pharmacology, Vitamin A physiology, 20-Hydroxysteroid Dehydrogenases metabolism, 3-Hydroxysteroid Dehydrogenases metabolism, Hydroxyprostaglandin Dehydrogenases metabolism, Retinaldehyde chemistry
- Abstract
Human AKR (aldo-keto reductase) 1C proteins (AKR1C1-AKR1C4) exhibit relevant activity with steroids, regulating hormone signalling at the pre-receptor level. In the present study, investigate the activity of the four human AKR1C enzymes with retinol and retinaldehyde. All of the enzymes except AKR1C2 showed retinaldehyde reductase activity with low Km values (~1 μM). The kcat values were also low (0.18-0.6 min-1), except for AKR1C3 reduction of 9-cis-retinaldehyde whose kcat was remarkably higher (13 min-1). Structural modelling of the AKR1C complexes with 9-cis-retinaldehyde indicated a distinct conformation of Trp227, caused by changes in residue 226 that may contribute to the activity differences observed. This was partially supported by the kinetics of the AKR1C3 R226P mutant. Retinol/retinaldehyde conversion, combined with the use of the inhibitor flufenamic acid, indicated a relevant role for endogenous AKR1Cs in retinaldehyde reduction in MCF-7 breast cancer cells. Overexpression of AKR1C proteins depleted RA (retinoic acid) transactivation in HeLa cells treated with retinol. Thus AKR1Cs may decrease RA levels in vivo. Finally, by using lithocholic acid as an AKR1C3 inhibitor and UVI2024 as an RA receptor antagonist, we provide evidence that the pro-proliferative action of AKR1C3 in HL-60 cells involves the RA signalling pathway and that this is in part due to the retinaldehyde reductase activity of AKR1C3.
- Published
- 2011
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130. Human and rodent aldo-keto reductases from the AKR1B subfamily and their specificity with retinaldehyde.
- Author
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Ruiz FX, Moro A, Gallego O, Ardèvol A, Rovira C, Petrash JM, Parés X, and Farrés J
- Subjects
- Aldehyde Reductase chemistry, Aldehyde Reductase genetics, Amino Acid Sequence, Animals, Binding Sites, Computational Biology, Cricetinae, Humans, Kinetics, Mice, Molecular Dynamics Simulation, Molecular Sequence Data, Mutagenesis, Site-Directed, Mutation, NADP metabolism, Protein Conformation, Rats, Substrate Specificity, Aldehyde Reductase metabolism, Retinaldehyde metabolism
- Abstract
NADP(H)-dependent cytosolic aldo-keto reductases (AKR) are mostly monomeric enzymes which fold into a typical (α/β)(8)-barrel structure. Substrate specificity and inhibitor selectivity are determined by interaction with residues located in three highly variable loops (A, B, and C). Based on sequence identity, AKR have been grouped into families, namely AKR1-AKR15, containing multiple subfamilies. Two human enzymes from the AKR1B subfamily (AKR1B1 and AKR1B10) are of special interest. AKR1B1 (aldose reductase) is related to secondary diabetic complications, while AKR1B10 is induced in cancer cells and is highly active with all-trans-retinaldehyde. Residues interacting with all-trans-retinaldehyde and differing between AKR1B1 and AKR1B10 are Leu125Lys and Val131Ala (loop A), Leu301Val, Ser303Gln, and Cys304Ser (loop C). Recently, we demonstrated the importance of Lys125 as a determinant of AKR1B10 specificity for retinoids. Residues 301 and 304 are also involved in interactions with substrates or inhibitors, and thus we checked their contribution to retinoid specificity. We also extended our study with retinoids to rodent members of the AKR1B subfamily: AKR1B3 (aldose reductase), AKR1B7 (mouse vas deferens protein), AKR1B8 (fibroblast-growth factor 1-regulated protein), and AKR1B9 (Chinese hamster ovary reductase), which were tested against all-trans isomers of retinaldehyde and retinol. All enzymes were active with retinaldehyde, but with k(cat) values (0.02-0.52 min(-1)) much lower than that of AKR1B10 (27 min(-1)). None of the enzymes showed oxidizing activity with retinol. Since these enzymes (except AKR1B3) have Lys125, other residues should account for retinaldehyde specificity. Here, by using site-directed mutagenesis and molecular modeling, we further delineate the contribution of residues 301 and 304. We demonstrate that besides Lys125, Ser304 is a major structural determinant for all-trans-retinaldehyde specificity of AKR1B10., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2011
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131. A systematic screen for protein-lipid interactions in Saccharomyces cerevisiae.
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Gallego O, Betts MJ, Gvozdenovic-Jeremic J, Maeda K, Matetzki C, Aguilar-Gurrieri C, Beltran-Alvarez P, Bonn S, Fernández-Tornero C, Jensen LJ, Kuhn M, Trott J, Rybin V, Müller CW, Bork P, Kaksonen M, Russell RB, and Gavin AC
- Subjects
- Algorithms, Fatty Acid-Binding Proteins analysis, Fatty Acid-Binding Proteins chemistry, Fatty Acid-Binding Proteins metabolism, Lipid-Linked Proteins analysis, Lipid-Linked Proteins chemistry, Lipid-Linked Proteins metabolism, Lipids analysis, Metabolome, Models, Biological, Protein Array Analysis methods, Protein Binding, Protein Interaction Domains and Motifs physiology, Saccharomyces cerevisiae metabolism, Saccharomyces cerevisiae Proteins chemistry, Validation Studies as Topic, High-Throughput Screening Assays methods, Lipid Metabolism physiology, Saccharomyces cerevisiae chemistry, Saccharomyces cerevisiae Proteins analysis, Saccharomyces cerevisiae Proteins metabolism
- Abstract
Protein-metabolite networks are central to biological systems, but are incompletely understood. Here, we report a screen to catalog protein-lipid interactions in yeast. We used arrays of 56 metabolites to measure lipid-binding fingerprints of 172 proteins, including 91 with predicted lipid-binding domains. We identified 530 protein-lipid associations, the majority of which are novel. To show the data set's biological value, we studied further several novel interactions with sphingolipids, a class of conserved bioactive lipids with an elusive mode of action. Integration of live-cell imaging suggests new cellular targets for these molecules, including several with pleckstrin homology (PH) domains. Validated interactions with Slm1, a regulator of actin polarization, show that PH domains can have unexpected lipid-binding specificities and can act as coincidence sensors for both phosphatidylinositol phosphates and phosphorylated sphingolipids.
- Published
- 2010
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132. Aldo-keto reductases from the AKR1B subfamily: retinoid specificity and control of cellular retinoic acid levels.
- Author
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Ruiz FX, Gallego O, Ardèvol A, Moro A, Domínguez M, Alvarez S, Alvarez R, de Lera AR, Rovira C, Fita I, Parés X, and Farrés J
- Subjects
- Alcohol Oxidoreductases genetics, Aldehyde Reductase, Aldo-Keto Reductases, Base Sequence, Biocatalysis, Cells, Cultured, Cloning, Molecular, DNA Primers, DNA, Complementary, HeLa Cells, Humans, Kinetics, Models, Molecular, Mutagenesis, Site-Directed, Retinoids metabolism, Substrate Specificity, Alcohol Oxidoreductases metabolism, Retinoids pharmacology, Tretinoin metabolism
- Abstract
NADP(H)-dependent cytosolic aldo-keto reductases (AKRs) have been added to the group of enzymes which contribute to oxidoreductive conversions of retinoids. Recently, we found that two members from the AKR1B subfamily (AKR1B1 and AKRB10) were active in the reduction of all-trans- and 9-cis-retinaldehyde, with K(m) values in the micromolar range, but with very different k(cat) values. With all-trans-retinaldehyde, AKR1B10 shows a much higher k(cat) value than AKR1B1 (18 min(-1)vs. 0.37 min(-1)) and a catalytic efficiency comparable to that of the best retinaldehyde reductases. Structural, molecular dynamics and site-directed mutagenesis studies on AKR1B1 and AKR1B10 point that subtle differences at the entrance of their retinoid-binding site, especially at position 125, are determinant for the all-trans-retinaldehyde specificity of AKR1B10. Substitutions in the retinoid cyclohexene ring, analyzed here further, also influence such specificity. Overall it is suggested that the rate-limiting step in the reaction mechanism with retinaldehyde differs between AKR1B1 and AKR1B10. In addition, we demonstrate here that enzymatic activity of AKR1B1 and AKR1B10 lowers all-trans- and 9-cis-retinoic acid-dependent trans-activation in living cells, indicating that both enzymes may contribute to pre-receptor regulation of retinoic acid and retinoid X nuclear receptors. This result supports that overexpression of AKR1B10 in cancer (an updated review on this topic is included) may contribute to dedifferentiation and tumor development.
- Published
- 2009
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133. The social network of a cell: recent advances in interactome mapping.
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Charbonnier S, Gallego O, and Gavin AC
- Subjects
- Social Support, Chromatography, Affinity trends, Gene Expression Profiling trends, Mass Spectrometry trends, Protein Interaction Mapping trends, Proteome metabolism, Signal Transduction physiology, Two-Hybrid System Techniques trends
- Abstract
Proteins very rarely act in isolation. Biomolecular interactions are central to all biological functions. In human, for example, interference with biomolecular networks often lead to disease. Protein-protein and protein-metabolite interactions have traditionally been studied one by one. Recently, significant progresses have been made in adapting suitable tools for the global analysis of biomolecular interactions. Here we review this suite of powerful technologies that enable an exponentially growing number of large-scale interaction datasets. These new technologies have already contributed to a more comprehensive cartography of several pathways relevant to human pathologies, offering a broader choice for therapeutic targets. Genome-wide scale analyses in model organisms reveal general organizational principles of eukaryotic proteomes. We also review the biochemical approaches that have been used in the past on a smaller scale for the quantification of the binding constant and the thermodynamics parameters governing biomolecular interaction. The adaptation of these technologies to the large-scale measurement of biomolecular interactions in (semi-)quantitative terms represents an important challenge.
- Published
- 2008
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134. Structural basis for the high all-trans-retinaldehyde reductase activity of the tumor marker AKR1B10.
- Author
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Gallego O, Ruiz FX, Ardèvol A, Domínguez M, Alvarez R, de Lera AR, Rovira C, Farrés J, Fita I, and Parés X
- Subjects
- Alcohol Oxidoreductases metabolism, Aldehyde Reductase metabolism, Aldo-Keto Reductases, Animals, Biomarkers, Tumor metabolism, COS Cells, Chlorocebus aethiops, Computer Simulation, Crystallography, X-Ray, Humans, Naphthalenes pharmacology, Protein Conformation, Protein Structure, Tertiary, Aldehyde Reductase chemistry, Aldehyde Reductase physiology, Gene Expression Regulation, Neoplastic, Oxidoreductases metabolism, Retinaldehyde chemistry, Tretinoin metabolism
- Abstract
AKR1B10 is a human aldo-keto reductase (AKR) found to be elevated in several cancer types and in precancerous lesions. In vitro, AKR1B10 exhibits a much higher retinaldehyde reductase activity than any other human AKR, including AKR1B1 (aldose reductase). We here demonstrate that AKR1B10 also acts as a retinaldehyde reductase in vivo. This activity may be relevant in controlling the first step of retinoic acid synthesis. Up-regulation of AKR1B10, resulting in retinoic acid depletion, may lead to cellular proliferation. Both in vitro and in vivo activities of AKR1B10 were inhibited by tolrestat, an AKR1B1 inhibitor developed for diabetes treatment. The crystal structure of the ternary complex AKR1B10-NADP(+)-tolrestat was determined at 1.25-A resolution. Molecular dynamics models of AKR1B10 and AKR1B1 with retinaldehyde isomers and site-directed mutagenesis show that subtle differences at the entrance of the retinoid-binding site, especially at position 125, are determinant for the all-trans-retinaldehyde specificity of AKR1B10. Substitutions in the retinaldehyde cyclohexene ring also influence the specificity. These structural features should facilitate the design of specific inhibitors, with potential use in cancer and diabetes treatments.
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- 2007
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135. New perspectives on an old disease: proteomics in cancer research.
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Gallego O and Gavin AC
- Subjects
- Biomarkers, Tumor blood, Humans, Neoplasm Proteins blood, Phosphorylation, Neoplasm Proteins metabolism, Neoplasms metabolism, Proteomics methods
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- 2007
- Full Text
- View/download PDF
136. What can nanotechnology do to fight cancer?
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Gallego O and Puntes V
- Subjects
- Animals, Antineoplastic Agents administration & dosage, Antineoplastic Agents therapeutic use, Biocompatible Materials, Contrast Media, Diagnostic Imaging methods, Drug Carriers, Drug Compounding, Drug Delivery Systems, Drug Design, Drug Screening Assays, Antitumor, Humans, Hyperthermia, Induced methods, Mice, Nanoparticles administration & dosage, Nanotubes, Carbon, Neoplasms diagnosis, Neoplasms drug therapy, Neoplasms, Experimental diagnosis, Quantum Dots, Nanotechnology methods, Nanotechnology trends, Neoplasms therapy
- Abstract
The marriage of physics, chemistry and biology at the namometric scale, nanotechnology, is a powerful technology which is predicted to have a large impacto on life sciences and particularly cancer treatment. In the following we will show some examples of applications which has already reached clinical treatments as new ideas which may positively influence the understanding, diagnosis and therapy of cancer.
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- 2006
- Full Text
- View/download PDF
137. Comparative functional analysis of human medium-chain dehydrogenases, short-chain dehydrogenases/reductases and aldo-keto reductases with retinoids.
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Gallego O, Belyaeva OV, Porté S, Ruiz FX, Stetsenko AV, Shabrova EV, Kostereva NV, Farrés J, Parés X, and Kedishvili NY
- Subjects
- Aldehyde Reductase, Aldo-Keto Reductases, Animals, Cell Line, Gene Expression Regulation, Enzymologic, Humans, Insecta, Acyl-CoA Dehydrogenase metabolism, Alcohol Oxidoreductases metabolism, Butyryl-CoA Dehydrogenase metabolism, Retinoids metabolism
- Abstract
Retinoic acid biosynthesis in vertebrates occurs in two consecutive steps: the oxidation of retinol to retinaldehyde followed by the oxidation of retinaldehyde to retinoic acid. Enzymes of the MDR (medium-chain dehydrogenase/reductase), SDR (short-chain dehydrogenase/reductase) and AKR (aldo-keto reductase) superfamilies have been reported to catalyse the conversion between retinol and retinaldehyde. Estimation of the relative contribution of enzymes of each type was difficult since kinetics were performed with different methodologies, but SDRs would supposedly play a major role because of their low K(m) values, and because they were found to be active with retinol bound to CRBPI (cellular retinol binding protein type I). In the present study we employed detergent-free assays and HPLC-based methodology to characterize side-by-side the retinoid-converting activities of human MDR [ADH (alcohol dehydrogenase) 1B2 and ADH4), SDR (RoDH (retinol dehydrogenase)-4 and RDH11] and AKR (AKR1B1 and AKR1B10) enzymes. Our results demonstrate that none of the enzymes, including the SDR members, are active with CRBPI-bound retinoids, which questions the previously suggested role of CRBPI as a retinol supplier in the retinoic acid synthesis pathway. The members of all three superfamilies exhibit similar and low K(m) values for retinoids (0.12-1.1 microM), whilst they strongly differ in their kcat values, which range from 0.35 min(-1) for AKR1B1 to 302 min(-1) for ADH4. ADHs appear to be more effective retinol dehydrogenases than SDRs because of their higher kcat values, whereas RDH11 and AKR1B10 are efficient retinaldehyde reductases. Cell culture studies support a role for RoDH-4 as a retinol dehydrogenase and for AKR1B1 as a retinaldehyde reductase in vivo.
- Published
- 2006
- Full Text
- View/download PDF
138. Relationship between drug resistance mutations, plasma viremia, and CD4+ T-cell counts in patients with chronic HIV infection.
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de Mendoza C, Martín-Carbonero L, Gallego O, Corral A, González-Lahoz J, and Soriano V
- Subjects
- Anti-HIV Agents pharmacology, Anti-HIV Agents therapeutic use, CD4 Lymphocyte Count, Chronic Disease, Genotype, HIV genetics, HIV Infections drug therapy, Humans, Multivariate Analysis, Mutation, RNA-Directed DNA Polymerase genetics, Viral Load, Viremia, Drug Resistance, Viral genetics, HIV drug effects, HIV Infections immunology, HIV Infections virology
- Abstract
Transmission of drug-resistant viruses has been shown to be associated with lower virus replication capacity and higher CD4+ cell counts in recent human immunodeficiency virus (HIV) seroconvertors. The impact of drug resistance mutations on CD4 cell counts in chronically HIV-infected patients has not been examined. A total of 825 patients whose plasma specimens were submitted to a reference laboratory for genotypic testing from 1999 to 2002 were analyzed. There was no significant difference in the median CD4+ cell count when comparing 63 drug-naive and 762 treatment-experienced patients [399 (IQR, 141-525) vs. 319 (IQR, 174-521); P = 0.8]. In contrast, the median viral load was significantly higher in drug-naive than in pre-treated patients [4.6 (IQR, 4.1-5.25) vs. 4.1 (IQR, 3.4-4.7) logs; P < 0.0001]. Overall, drug resistance mutations appeared in 81% of patients, with a median number of 9 (IQR, 5-14). The rate of drug resistance genotypes was 9.5% for drug-naive patients and 86.7% for pre-treated individuals. In the univariate analysis, a lower viral load (P < 0.0001), the presence of drug-resistant viruses (P = 0.038), and specific mutations in the reverse transcriptase (RT) gene [presence of M184V (P = 0.016) or K70R (P < 0.0001), and lack of L74V (P < 0.003)] were all associated with higher CD4+ counts. However, in the multivariate analyses, only a lower viral load and the presence of K70R were significantly associated with higher CD4+ cell counts. In summary, drug-resistant viruses are associated with lower viral loads, but after adjusting for plasma viremia, subjects carrying drug-resistant viruses do not show significantly higher CD4 cell counts. Thus, keeping on treatment HIV-infected individuals failing virologically and harboring drug-resistant viruses may ameliorate their immunological deterioration until new drugs became available., (Copyright 2005 Wiley-Liss, Inc.)
- Published
- 2005
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139. Estimated extent of cross-resistance to ritonavir-boosted protease inhibitors among protease inhibitors-experienced patients: implications for tipranavir use.
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Gallego O, de Mendoza C, Corral A, Barrios A, and Soriano V
- Subjects
- HIV Protease Inhibitors pharmacokinetics, Humans, Mutation, Sulfonamides, Drug Resistance, Multiple, Viral genetics, HIV Infections drug therapy, HIV Protease Inhibitors pharmacology, Pyridines pharmacology, Pyrones pharmacology, Ritonavir pharmacology
- Published
- 2005
- Full Text
- View/download PDF
140. Higher efavirenz concentrations determine the response to viruses carrying non-nucleoside reverse transcriptase resistance mutations.
- Author
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González de Requena D, Gallego O, Corral A, Jiménez-Nácher I, and Soriano V
- Subjects
- Alkynes, Anti-HIV Agents therapeutic use, Benzoxazines, Cyclopropanes, HIV Infections blood, Humans, Nevirapine therapeutic use, Oxazines blood, Reverse Transcriptase Inhibitors blood, Treatment Failure, Viral Load, Drug Resistance, Viral genetics, HIV Infections drug therapy, HIV-1 genetics, Mutation genetics, Oxazines therapeutic use, Reverse Transcriptase Inhibitors therapeutic use
- Abstract
We examined the influence of both efavirenz plasma concentrations and non-nucleoside reverse transcriptase (NNRTI) resistance mutations on the antiviral activity of efavirenz in patients experiencing early virological failure under nevirapine-containing regimens. Up to 41% of patients reach less than 50 copies/ml at 48 weeks. No association was found between the presence of NNRTI resistance mutations and virological outcome. Nevertheless, patients responding virologically and carrying NNRTI-resistant viruses had higher efavirenz levels than those who did not respond.
- Published
- 2004
- Full Text
- View/download PDF
141. Kinetics of human alcohol dehydrogenase with ring-oxidized retinoids: effect of Tween 80.
- Author
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Martras S, Alvarez R, Gallego O, Domínguez M, de Lera AR, Farrés J, and Parés X
- Subjects
- Alcohol Dehydrogenase drug effects, Alcohol Dehydrogenase genetics, Alcohol Dehydrogenase isolation & purification, Escherichia coli genetics, Humans, Kinetics, Molecular Structure, Oxidation-Reduction, Reproducibility of Results, Retinoids chemistry, Substrate Specificity, Alcohol Dehydrogenase metabolism, Polysorbates pharmacology, Retinoids metabolism
- Abstract
Human alcohol dehydrogenases (ADH1 and ADH4) actively use retinoids oxidized at the cyclohexenyl ring (4-oxo-, 4-hydroxy-, and 3,4-didehydro-retinoids), which are functional compounds in several cells and tissues (i.e., in human skin). Remarkably, activities with 4-oxo-retinal and 4-hydroxy-retinol (kcat = 2050 min(-1) for ADH4) are the highest among retinoids, similar to those of the best aliphatic alcohols. Thus, ADH1 and ADH4 provide a metabolic pathway for the synthesis of the corresponding retinoic acids. Tween 80, a widely used detergent in the retinoid activity assay, behaves as a competitive inhibitor. The Km values for all-trans-retinol (2-3 microM), estimated in the absence of detergent, are 10-fold lower than those obtained at the usual 0.02% Tween 80. This suggests a contribution of ADH to retinoid metabolism more relevant than previously expected. However, Tween 80 stabilizes retinoids in water solution and provides a reliable and reproducible assay, suitable for comparing different ADHs and different retinoid substrates.
- Published
- 2004
- Full Text
- View/download PDF
142. Correlation between rules-based interpretation and virtual phenotype interpretation of HIV-1 genotypes for predicting drug resistance in HIV-infected individuals.
- Author
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Gallego O, Martin-Carbonero L, Aguero J, de Mendoza C, Corral A, and Soriano V
- Subjects
- Adenine pharmacology, Amino Acid Substitution, Didanosine pharmacology, Dideoxynucleosides pharmacology, Genotype, HIV Infections drug therapy, Humans, Microbial Sensitivity Tests, Mutation, Nucleosides pharmacology, Organophosphonates pharmacology, Phenotype, Protease Inhibitors pharmacology, Reverse Transcriptase Inhibitors pharmacology, Tenofovir, Adenine analogs & derivatives, Anti-HIV Agents pharmacology, Drug Resistance, Viral genetics, HIV Infections virology, HIV-1 drug effects, HIV-1 genetics
- Abstract
Drug resistance testing provides useful information for managing HIV-infected patients. Phenotyping could add complementary information to genotyping and occasionally be more useful, although is less available to clinicians. Large paired geno-pheno databases have allowed the prediction of phenotypes from genotypes. However, the accuracy of these virtual phenotypes (vPT) in a clinical setting has not been well assessed yet. We analyzed the concordance between vPT and interpreted genotype (GT) in 105 samples belonging to treatment-experienced HIV-infected patients. A high concordance was seen when examining both non-nucleoside reverse transcriptase inhibitors (NNRTI) and protease inhibitors (PI) (r = 0.95 either), while it was lower for nucleoside analogs (r = 0.79). The drugs with lower concordance were abacavir (71.1%), tenofovir (71.5%) and didanosine (71.9%). In 20% of specimens (21/105), the vPT did not provide results for all approved drugs. These were mainly samples with a high number of drug resistance mutations or rare genotypes, which seem to be underepresented in the VircoNET database. Overall, there is good correlation between vPT/GT, especially for PI and NNRTI. The inclusion of additional sequences in the VircoNET database, mainly those derived from heavily treatment-experienced patients and/or from patients failing the most recently approved drugs might improve its performance.
- Published
- 2004
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- View/download PDF
143. Predictors of virological response to atazanavir in protease inhibitor-experienced patients.
- Author
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Barrios A, Rendón AL, Gallego O, Martín-Carbonero L, Valer L, Ríos P, Maida I, García-Benayas T, Jiménez-Nácher I, González-Lahoz J, and Soriano V
- Subjects
- Adult, Atazanavir Sulfate, CD4 Lymphocyte Count, Female, HIV Infections drug therapy, HIV Protease Inhibitors administration & dosage, HIV Protease Inhibitors adverse effects, HIV Protease Inhibitors blood, HIV Protease Inhibitors therapeutic use, HIV-1 genetics, Humans, Male, Oligopeptides administration & dosage, Oligopeptides adverse effects, Oligopeptides blood, Oligopeptides therapeutic use, Predictive Value of Tests, Pyridines administration & dosage, Pyridines adverse effects, Pyridines blood, Pyridines therapeutic use, RNA, Viral analysis, Retrospective Studies, Viral Load, Drug Resistance, Viral genetics, HIV Infections virology, HIV Protease Inhibitors pharmacology, HIV-1 drug effects, Oligopeptides pharmacology, Pyridines pharmacology
- Abstract
Background: Atazanavir (ATV) is the latest approved HIV protease inhibitor (PI). Even though it is very convenient (only two capsules once a day), concerns have risen about its potency., Method: The clinical performance of ATV 400 mg once a day was examined in all PI-experienced patients who were included in the ATV expanded access program conducted in a single institution. The predictive value of baseline drug resistance HIV genotypes, ATV plasma trough levels, and the genotypic inhibitory quotient (GIQ) on the virological response at week 24 was assessed., Results: Data from 92 patients were analyzed. ATV was prescribed as part of a rescue intervention (45%), a simplification strategy (11%), or an attempt to ameliorate hyperlipidemias (23%) or other toxicities (16%). Tenofovir (TDF) was concomitantly used with ATV in 78% of patients. None received ritonavir boosting. In patients with detectable viremia at baseline (65%), the median HIV RNA drop was 0.7 logs. The median ATV Cmin was 0.12 microg/mL (IQR, 0.05-0.22 microg/mL), which is clearly above the IC90 (90% inhibitory concentration) for ATV in wild-type viruses. The virological response did not correlate significantly with ATV Cmin. The median number of protease resistance mutations was lower in patients showing virological response than in nonresponders (1 vs. 5; p=.07). A higher HIV RNA drop was associated with a higher GIQ (p=.02; beta=-5.4; 95% CI, -10 to -1). Only 4 patients (4%) discontinued treatment due to ATV-related toxicities (hyperbilirubinemia in 1). Bilirubin levels were associated with ATV plasma concentrations (p=.05; beta=3.2; 95% CI, -0.1 to 6.5). The rate of hypertriglyceridemia and hypercholesterolemia declined significantly with respect to baseline., Conclusion: ATV is relatively safe and provides significant virological response in PI-experienced patients, mainly among those with a low number of protease resistance mutations. The GIQ predicts accurately the virological response in patients receiving ATV. Hyperbilirubinemia is associated with higher ATV plasma levels.
- Published
- 2004
- Full Text
- View/download PDF
144. The specificity of alcohol dehydrogenase with cis-retinoids. Activity with 11-cis-retinol and localization in retina.
- Author
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Martras S, Alvarez R, Martínez SE, Torres D, Gallego O, Duester G, Farrés J, de Lera AR, and Parés X
- Subjects
- Animals, Humans, Immunohistochemistry, Isoenzymes metabolism, Kinetics, Mice, Rats, Rats, Sprague-Dawley, Substrate Specificity, Alcohol Dehydrogenase metabolism, Retina enzymology, Vitamin A metabolism
- Abstract
Studies in knockout mice support the involvement of alcohol dehydrogenases ADH1 and ADH4 in retinoid metabolism, although kinetics with retinoids are not known for the mouse enzymes. Moreover, a role of alcohol dehydrogenase (ADH) in the eye retinoid interconversions cannot be ascertained due to the lack of information on the kinetics with 11-cis-retinoids. We report here the kinetics of human ADH1B1, ADH1B2, ADH4, and mouse ADH1 and ADH4 with all-trans-, 7-cis-, 9-cis-, 11-cis- and 13-cis-isomers of retinol and retinal. These retinoids are substrates for all enzymes tested, except the 13-cis isomers which are not used by ADH1. In general, human and mouse ADH4 exhibit similar activity, higher than that of ADH1, while mouse ADH1 is more efficient than the homologous human enzymes. All tested ADHs use 11-cis-retinoids efficiently. ADH4 shows much higher k(cat)/K(m) values for 11-cis-retinol oxidation than for 11-cis-retinal reduction, a unique property among mammalian ADHs for any alcohol/aldehyde substrate pair. Docking simulations and the kinetic properties of the human ADH4 M141L mutant demonstrated that residue 141, in the middle region of the active site, is essential for such ADH4 specificity. The distinct kinetics of ADH4 with 11-cis-retinol, its wide specificity with retinol isomers and its immunolocalization in several retinal cell layers, including pigment epithelium, support a role of this enzyme in the various retinol oxidations that occur in the retina. Cytosolic ADH4 activity may complement the isomer-specific microsomal enzymes involved in photopigment regeneration and retinoic acid synthesis.
- Published
- 2004
- Full Text
- View/download PDF
145. Prevalence of drug resistance genotypes causing broad cross-resistance to nucleos(t)ide analogues.
- Author
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Gallego O, de Mendoza C, Corral A, and Soriano V
- Subjects
- Genotype, HIV Infections virology, HIV-1 drug effects, Humans, Mutation, RNA-Directed DNA Polymerase genetics, Anti-HIV Agents therapeutic use, Drug Resistance, Multiple, Viral genetics, HIV Infections drug therapy, HIV-1 genetics, Reverse Transcriptase Inhibitors therapeutic use
- Published
- 2004
- Full Text
- View/download PDF
146. Prediction of virological response to lopinavir/ritonavir using the genotypic inhibitory quotient.
- Author
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González de Requena D, Gallego O, Valer L, Jiménez-Nácher I, and Soriano V
- Subjects
- Adult, Female, Genotype, HIV Infections virology, HIV Protease drug effects, HIV Protease Inhibitors pharmacology, HIV-1 enzymology, HIV-1 genetics, Humans, Lopinavir, Male, Mutation, Predictive Value of Tests, Pyrimidinones pharmacology, RNA, Viral blood, Ritonavir pharmacology, Salvage Therapy, Viral Load, Drug Resistance, Viral genetics, HIV Protease genetics, HIV Protease Inhibitors pharmacokinetics, HIV-1 drug effects, Pyrimidinones pharmacokinetics, Ritonavir pharmacokinetics
- Abstract
The predictive value of virological response to lopinavir (LPV)/ritonavir (r) was assessed in 126 HIV-infected patients who failed antiretroviral therapy and had begun a rescue intervention based on LPV/r. At 3 months, subjects with < or =6 protease (PRO) resistance mutations showed a higher rate of virological response (HIV-RNA drop > 1 log or to <50 copies/ml) than patients with >6 PRO resistance mutations (77% versus 48%; p = 0.01). On the other hand, virological responders had greater mean LPV plasma trough levels than nonresponders (6.4 versus 3.9 microg/ml; p = 0.02). A positive correlation was found between LPV trough concentration and viral load reductions at 3 months under LPV/r (r = 0.23; p = 0.017). Overall, virological response was seen in 80.8% of patients with LPV trough levels >4.8 microg/ml while in only 52.5% of patients with lower LPV trough concentrations (p = 0.002). In the multivariate analysis, both < or =6 PRO resistance mutations and LPV trough levels >4.8 microg/ml were independent predictors of virological response to salvage therapy with LPV/r. A genotypic inhibitory quotient (GIQ) was estimated for each patient based on the ratio between LPV trough levels and the number of PRO resistance mutations. A positive strong correlation was found between GIQ and viral load reductions (r = 0.42; p = 0.002). Virological response was seen in 78% of patients with a GIQ >0.7 but only in 41.6% of those with lower GIQ (p = 0.004). When LPV trough levels >4.8 microg/ml, PRO resistance mutations < or =6, and GIQ >0.7 were all included in a stepwise multivariate analysis, GIQ remained as the main independent predictor of response to LPV/r.
- Published
- 2004
- Full Text
- View/download PDF
147. Long-term outcome of HIV-infected patients with multinucleoside-resistant genotypes.
- Author
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Gallego O, d Mendoza C, Labarga P, Altisent C, González J, García-Alcalde I, Valer L, Valencia E, and Soriano V
- Subjects
- Adolescent, Adult, CD4 Lymphocyte Count, Female, Genotype, HIV Infections blood, HIV-1 genetics, Humans, Male, Middle Aged, Mutation, RNA, Viral analysis, Reverse Transcriptase Polymerase Chain Reaction, Salvage Therapy, Survivors, Treatment Outcome, Viral Load, Anti-HIV Agents therapeutic use, Drug Resistance, Viral genetics, HIV Infections drug therapy
- Abstract
Background: Multiple resistance to nucleoside analogs mediated by the Q151M complex and/or codon 67-69 inserts/deletions represents a growing problem among HIV-infected persons, most of whom have been exposed to sequential therapies for long periods of time., Patients and Method: All plasma samples collected from HIV-infected patients failing antiretroviral therapy and referred for HIV genotyping to our institution during the last 3 years were examined. Genetic analysis of the reverse transcriptase (RT) and protease (PR) genes was performed using an automatic sequencer., Results: Multinucleoside-resistance (MNR) genotypes were recognized in 22 (2.9%) of 761 participants. Twelve of them carried the Q151M complex and 9 harbored different codon 67-69 inserts. One participant carried a deletion at codon 67 of the RT gene. All patients with MNR viruses had been exposed to nucleoside analogs for a median of 54 months (range, 19-96). The mean plasma HIV RNA at the time MNR was first identified was 4.62 log and the mean CD4 count was 227 cells/microL. All patients with MNR viruses except two began salvage therapies based on protease inhibitors (PIs). Overall, 54.5% (12/22) of participants showed a significant virologic response (defined as >1 log reduction in plasma HIV RNA). Seven of them reached <50 copies/mL and remained with undetectable viremia for a median of 17 months (range, 8-50). No differences were found when patients with Q151M and codon 67-69 rearrangements were compared. The only predictor of response was the inclusion of ritonavir-boosted PI in the salvage regimen. In all patients with virologic failure, MNR genotypes have persisted over time., Conclusion: The prevalence of viruses with MNR genotypes is currently low (approximately 3%) among HIV-infected patients failing antiretroviral therapy. The expected poor prognosis of patients harboring MNR viruses may often be overcome using rescue interventions based on potent ritonavir-boosted PI combinations.
- Published
- 2003
- Full Text
- View/download PDF
148. Human aldose reductase and human small intestine aldose reductase are efficient retinal reductases: consequences for retinoid metabolism.
- Author
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Crosas B, Hyndman DJ, Gallego O, Martras S, Parés X, Flynn TG, and Farrés J
- Subjects
- Alcohol Oxidoreductases chemistry, Aldehyde Reductase chemistry, Animals, Binding Sites, Chromatography, High Pressure Liquid, Humans, Kinetics, Swine, Alcohol Oxidoreductases metabolism, Aldehyde Reductase metabolism, Intestine, Small enzymology, Retinoids metabolism
- Abstract
Aldo-keto reductases (AKRs) are NAD(P)H-dependent oxidoreductases that catalyse the reduction of a variety of carbonyl compounds, such as carbohydrates, aliphatic and aromatic aldehydes and steroids. We have studied the retinal reductase activity of human aldose reductase (AR), human small-intestine (HSI) AR and pig aldehyde reductase. Human AR and HSI AR were very efficient in the reduction of all- trans -, 9- cis - and 13- cis -retinal ( k (cat)/ K (m)=1100-10300 mM(-1).min(-1)), constituting the first cytosolic NADP(H)-dependent retinal reductases described in humans. Aldehyde reductase showed no activity with these retinal isomers. Glucose was a poor inhibitor ( K (i)=80 mM) of retinal reductase activity of human AR, whereas tolrestat, a classical AKR inhibitor used pharmacologically to treat diabetes, inhibited retinal reduction by human AR and HSI AR. All- trans -retinoic acid failed to inhibit both enzymes. In this paper we present the AKRs as an emergent superfamily of retinal-active enzymes, putatively involved in the regulation of retinoid biological activity through the assimilation of retinoids from beta-carotene and the control of retinal bioavailability.
- Published
- 2003
- Full Text
- View/download PDF
149. Indinavir plasma concentrations and resistance mutations in patients experiencing early virological failure.
- Author
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González de Requena D, Gallego O, de Mendoza C, Corral A, Jiménez-Nácher I, and Soriano V
- Subjects
- Anti-HIV Agents therapeutic use, Drug Therapy, Combination, HIV Infections virology, HIV Protease genetics, HIV Protease Inhibitors pharmacology, HIV Protease Inhibitors therapeutic use, HIV Reverse Transcriptase genetics, Humans, Indinavir pharmacology, Indinavir therapeutic use, Reverse Transcriptase Inhibitors therapeutic use, Treatment Failure, Drug Resistance, Viral genetics, HIV Infections drug therapy, HIV Protease Inhibitors blood, HIV-1 drug effects, Indinavir blood, Mutation
- Abstract
Virological failure under protease inhibitor (PI)-based antiretroviral regimens is often not explained by the selection of resistance mutations. The role of low indinavir (IDV) plasma levels in treatment failure was assessed in 46 subjects experiencing early virological failure to a first-line IDV-containing triple combination. Overall, 69% of patients showed subtherapeutic IDV plasma levels (it was not detected at all in 75% of them). Subjects with detectable but suboptimal IDV levels developed more IDV resistance mutations. Thus, drug monitoring may be useful to assess treatment adherence and risk of drug resistance in early virological failures. This information may be crucial for choosing the most appropriate rescue intervention.
- Published
- 2003
- Full Text
- View/download PDF
150. High rate of resistance to antiretroviral drugs among HIV-infected prison inmates.
- Author
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Gallego O, Corral A, De Mendoza C, Gonzalez-Lahoz J, and Soriano V
- Subjects
- Endopeptidases blood, HIV drug effects, Humans, RNA, Viral blood, RNA, Viral isolation & purification, RNA-Directed DNA Polymerase blood, Retrospective Studies, Spain, Viral Load, Anti-HIV Agents therapeutic use, Drug Resistance, Viral, HIV genetics, HIV Infections drug therapy, Mutation, Prisoners
- Abstract
Background: Resistance to antiretroviral (ARV) drugs represents a major obstacle to the success of HIV therapy. The aim of the study was to examine the prevalence of genotypic resistance to ARV drugs in a large group of HIV-infected individuals incarcerated in penal facilities., Material/methods: We analyzed the reverse transcriptase and protease genes on plasma samples collected from 309 HIV-infected prison inmates in Madrid. In order to compare the prevalence of resistance at different periods and detect any trend over time, half of the samples from ARV-naive and half from pre-treated subjects were randomly collected in 1999 and in 2001., Results: Overall, 63.7% of specimens harbored plasma HIV-RNA above 1000 copies/ml. Genotypic data were obtained in 94.4% of them. Primary resistance mutations among 127 drug-naive subjects were recognized in 13% in 1999 vs. 15% in 2001. In contrast, drug resistance was found in 35% and 59% of 182 pre-treated subjects in 1999 and 2001., Conclusions: Drug resistance has increased over the last two years among inmates on ARV drugs and currently affects 59% of those failing treatment. A nearly 3-fold increase has been noticed for NNRTI resistance. In comparison with HIV-positive subjects outside jail on ARV drugs, prisoners are more likely to experience virological failure, but show a lower rate of drug resistance; this affects particularly drugs with a low genetic barrier (i.e. NNRTI and 3TC).
- Published
- 2003
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