Evaluating ZNF217 mRNA Expression Levels as a Predictor of Response to Endocrine Therapy in ER+ Breast Cancer

ZNF217 is a candidate oncogene with a wide variety of deleterious functions in breast cancer. Here, we aimed at investigating in a pilot prospective study the association between ZNF217 mRNA expression levels and the clinical response to neoadjuvant endocrine therapy (ET) in postmenopausal ER-positive (ER C) breast cancer patients. Core surgical biopsy samples before treatment initiation and post-treatment were obtained from 68 patients, and Ki-67 values measured by immunohistochemistry (IHC) were used to identify responders (n = 59) and non-responders (n = 9) after 4 months of ET. We report for the first time that high ZNF217 mRNA expression level measured by RT-qPCR in the initial tumor samples (pre-treatment) is associated with poor response to neoadjuvant ET. Indeed, the clinical positive response rate in patients with low ZNF217 expression levels was significantly higher than that in those with high ZNF217 expression levels (P = 0.027). Additionally, a retrospective analysis evaluating ZNF217 expression levels in primary breast tumor of ER+/HER2-/LNO breast cancer patients treated with adjuvant ET enabled the identification of poorer responders prone to earlier relapse (P = 0.013), while ZNF217 did not retain any prognostic value in the ER+/HER2-/LNO breast cancer patients who did not receive any treatment. Altogether, these data suggest that ZNF217 expression might be predictive of clinical response to ET

Molecular events associated with acquired resistance to aromatase inhibitors in hormone-dependent breast cancer : the PI3K/Akt/mTOR survival pathway : specific expression profiles of miRNAs

La résistance aux anti-aromatases (AAs) constitue un obstacle thérapeutique majeur dans le traitement des cancers du sein RE+. Les objectifs de ce travail étaient : (i) de caractériser les événements moléculaires associés à la résistance acquise aux AAs ; (ii) d’identifier de manière globale de nouveaux profils de miRNAs spécifiquement associés à la résistance aux AAs. Notre étude a mis en évidence le rôle central de la voie Akt/mTOR dans la résistance acquise et de novo aux AAs dans des modèles cellulaires, mais également dans des échantillons de patientes ayant récidivé sous anastrozole. La combinaison d’un AA avec le MK-2206, inhibiteur d’Akt ou avec la rapamycine, inhibiteur de mTOR, augmente la sensibilité à l’AA dans les cellules contrôles et est suffisante pour surmonter la résistance et restaurer la sensibilité à l'hormonothérapie dans les cellules résistantes. Notre travail propose également un modèle de résistance acquise aux AAs basé sur la sélection de cellules « cancer-initiating-like » dotées de propriétés d'auto-renouvellement, d’une résistance intrinsèque aux AAs et d’une sensibilité au MK-2206. Notre étude à grande échelle des miRNAs a identifié la voie Akt/mTOR comme une des cibles privilégiées de ces miRNAs. Nous avons identifié et validé trois miRNAs dérégulés capables de moduler le statut d’activation de la voie Akt/mTOR, qui représentent des cibles potentielles. En conclusion, notre projet a mis en évidence de nouvelles voies de signalisations ciblées par ces miRNAs et de nouveaux évènements moléculaires, qui représentent des candidats potentiels dans la résistance aux AAsResistance to aromatase inhibitors (AIs) remains a major drawback in the treatment of ER+ breast cancers. Our objectives were (i) to characterize molecular events associated with acquired AI resistance (ii) to capture a global view of the miRNA expression profiles associated with AI resistance. Our results showed the major role of the Akt/mTOR pathway in both de novo and acquired resistance to AI in cellular models and also in breast tumors of patients who relapsed under anastrozole. Combining AI with the Akt inhibitor MK-2206 or with the mTOR inhibitor rapamycin increased sensitivity to this AI in the control cells and was sufficient to overcome resistance and restore sensitivity to endocrine therapy in the resistant cells. Our findings propose a model of AI-acquired resistance based on the selection of cancer-initiating-like cells possessing self-renewing properties, intrinsic resistance to AI and sensitivity to MK-2206. Our large-scale study identified the Akt/mTOR pathway as one of the main targets of the deregulated miRNAs. We identified and validated three miRNAs able to modulate the Akt/mTOR activation status, suggesting these miRNAs as potential targets. To conclude, our project identified new miRNA-targeted signaling pathways and new molecular events, representing strong candidates in the mediation of AI resistanc

Evolution vers une médecine personnalisée de la prise en charge thérapeutique du cancer du sein

Le cancer du sein est classiquement réparti selon des critères anatomo-pathologiques en trois sous-types majeurs: hormona-dépendant, Human Epidermal Growth Factor Receptor-2 positif et triple négatif. Le développement récent des technologies à haut débit a permis de mieux appréhender l'hétérogénéité du cancer du sein en révélant l'existence d'une multitude d'entités moléculaires au sein de ces trois sous-types. Malgré l'enthousiasme généré autour des thérapies ciblées, l'efficacité clinique de ces molécules demeure encore limitée. Une des approches actuelles pour surmonter ce problème est de mieux sélectionner les patientes pouvant bénéficier d'une thérapie ciblée donnée en se basant sur les données moléculaires de chaque patiente. Cette personnalisation de la prise en charge des patientes va très prochainement modifier en profondeur la façon de développer et d'évaluer les nouvelles molécules. L'émergence de la médecine personnalisée constitue donc un véritable défi nécessitant une coordination multi-disciplinaire englobant des compétences scientifiques, pharmaceutiques et médicales multiples pour sa mise en place en pratique cliniqueLYON1-BU Santé (693882101) / SudocSudocFranceF

Benchmarking of Amplicon-Based Next-Generation Sequencing Panels Combined with Bioinformatics Solutions for Germline BRCA1 and BRCA2 Alteration Detection

International audienceThe recent deployment of next-generation sequencing approaches in routine laboratory analysis has considerably modified the landscape of BRCA1 and BRCA2 germline alteration detection in patients with a high risk of developing breast and/or ovarian cancer. Several commercial multiplex amplicon-based panels and bioinformatics solutions are currently available. In this study, we evaluated the combinations of several BRCA testing assays and bioinformatics solutions for the identification of single-nucleotide variants, insertion/deletion variants, and copy number variations (CNVs). Four assays (BRCA Tumor, BRCA HC, Ion AmpliSeq BRCA, and Access Array BRCA) and two commercial bioinformatics solutions (SeqNext software version 4.3.1 and Sophia DDM version 5.0.13) were tested on a set of 28 previously genotyped samples. All solutions exhibited accurate detection of single-nucleotide variants and insertion/deletion variants, except for Ion AmpliSeq BRCA, which exhibited a decrease in coverage. Of interest, for CNV analysis, the best accuracy was observed with the Sophia DDM platform regardless of the BRCA kit used. Finally, the performance of the most relevant combination (BRCA Tumor and Sophia DDM) was blindly validated on an independent set of 152 samples. Altogether, our results emphasize the need to accurately compare and control both molecular next-generation sequencing approaches and bioinformatics pipelines to limit the number of discrepant alterations and to provide a powerful tool for reliable detection of genetic alterations in BRCA1 and BRCA2, notably CNVs

Premature termination codons in SOD1 causing Amyotrophic Lateral Sclerosis are predicted to escape the nonsense-mediated mRNA decay

International audienceAmyotrophic lateral sclerosis (ALS) is the most common and severe adult-onset motoneuron disease and has currently no effective therapy. Approximately 20% of familial ALS cases are caused by dominantly-inherited mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1), which represents one of the most frequent genetic cause of ALS. Despite the overwhelming majority of ALS-causing missense mutations in SOD1, a minority of premature termination codons (PTCs) have been identified. mRNA harboring PTCs are known to be rapidly degraded by nonsense-mediated mRNA decay (NMD), which limits the production of truncated proteins. The rules of NMD surveillance varying with PTC location in mRNA, we analyzed the localization of PTCs in SOD1 mRNA to evaluate whether or not those PTCs can be triggered to degradation by the NMD pathway. Our study shows that all pathogenic PTCs described in SOD1 so far can theoretically escape the NMD, resulting in the production of truncated protein. This finding supports the hypothesis that haploinsufficiency is not an underlying mechanism of SOD1 mutant-associated ALS and suggests that PTCs found in the regions that trigger NMD are not pathogenic. Such a consideration is particularly important since the availability of SOD1 antisense strategies, in view of variant treatment assignment

Metallic oxide defect luminescent emission for application in solar cells and WLEDs

International audienceThe diversity of applications in optoelectronics, solar cells, light emitting diodes (LEDs), sensors and catalysis, as well as medical diagnostics profits from unique and attractive properties of and metal oxide nanostructures. In the present communication we report the fabrication methods and the properties of the metallic oxide nanostructures for solar cell and white light emitting diode applications (WLEDs). Zinc oxide and gallium oxide are wide bandgap semiconductors (3,37 eV and 4,8 eV for ZnO and beta-Ga2O3, respectively) and their nanostructures are of increasing interest because they have a variety of intrinsic defects that produce light emission in the visible range without the introduction of additional critical elements (doping). As technological costs and environmental concerns such as the use of critical metals or the issue of recycling become decision parameters, industrial fabrication methods should be cheap and harmless to humans, aquatic and terrestrial organisms, and the environment. To develop the studied nanostructures, hydrolysis method was used to synthesize ZnO nanoparticles and the Physical Vapor Deposition (PVD) for the fabrication of alpha-Ga2O3 and beta-Ga2O3. The obtained materials were characterized using various techniques. The XRD data and scanning electron microscopy (SEM)confirm the presence of nanoparticles and alpha and beta-Ga2O3 phases. Raman spectroscopy confirms the presence of some disorder for both ZnO and Ga2O3, characteristic of the presence of the defects. We discuss the effects of the nanoparticle size, the morphology and the surface stabilization on the enhancement of the PL QY in case of the ZnO NPs and of the PVD conditions for alpha- and beta-Ga2O3 thin layers. The photoluminescent emission of the studied materials is also examined, in order to achieve a perfect control of the defect emission to increase its efficiency. This opens up the prospect of synthesizing phosphors without rare earth for white LEDs, solar cells and whose spectrum can be tuned to render warm or cold white light, by a fabrication process easy to implement industrially and with a low environmental impact

Structure, chemical analysis, and ferroelectric properties of chemical solution derived epitaxial PbZr0.2_{0.2}Ti0.8_{0.8}O3_3 films for nanomechanical switching

National audienceFerroelectrics are a material class characterized by the presence of a spontaneous polarization, which can be switched under electrical and mechanical stimuli. Switching phenomena is a complex process entangled to electronic, chemistry and (micro)structural properties, and intrinsic and extrinsic defects, all these phenomena happening within the ferroelectric object and at its physical boundaries. Considering these phenomena becomes critical in the framework of ferroelectric nanostructures, e.g. integrated thin films, where interfaces and surfaces effects dominate against volume related properties.Here we present the investigation of mechanical and electrical polarization switching on the prototypical tetragonal ferroelectric PbZr0.2Ti0.8O3 (PZT) thin films. Using different routes for chemical solution derived processing and rapid thermal annealing crystallization of epitaxial PZT thin films, we gain control over the electrical properties, chemistry and microstructure of thin films of different thickness. The ferroelectric properties obtained from microcapacitors underline that polarization switching behaviors under electric field are compatible with out-of-plane c-oriented tetragonal PZT, depicting remnant polarization values close to bulk ones for film thickness above 100 nm. Interestingly, a decrease of measured remnant polarization and larger leakage current are observed in capacitors based on films with thickness below 100 nm as well as in those undergoing different crystallization processes. To understand the nanoscale nature of the ferroelectric properties of these films, we used atomic force microscopy (AFM) derived techniques, i.e. piezoresponse force microscopy and local piezoelectric hysteresis loops [1]. Through application of voltage and/or pressure using the AFM-tip, within different electrical boundary conditions, we studied the nucleation and switching phenomena in as grown and in electrically and pressure-induced patterned ferroelectric domains. Results on the coercive electric fields and threshold forces required for polarization switching of PZT films are analyzed in view not only of the different electrical and mechanical poling, but also on the microstructure, film density, defects and chemical composition determined from X-ray diffraction, scanning electron transmission microscopy and electron energy loss spectroscopy, Rutherford backscattering and secondary ion mass spectroscopies.Polarization switching results of PZT films both at the micro- and nano-scales underline that the robust ferroelectric properties and switching mechanisms arise from reproducible chemistry, (micro)structure and defect distribution over thickness in chemical solution derived PZT films. These results will be discussed in the framework of integrated ferroelectric films for nanomechanical applications

Structure, chemical analysis, and ferroelectric properties of chemical solution derived epitaxial PbZr0.2_{0.2}Ti0.8_{0.8}O3_3 films for nanomechanical switching

National audienceFerroelectrics are a material class characterized by the presence of a spontaneous polarization, which can be switched under electrical and mechanical stimuli. Switching phenomena is a complex process entangled to electronic, chemistry and (micro)structural properties, and intrinsic and extrinsic defects, all these phenomena happening within the ferroelectric object and at its physical boundaries. Considering these phenomena becomes critical in the framework of ferroelectric nanostructures, e.g. integrated thin films, where interfaces and surfaces effects dominate against volume related properties.Here we present the investigation of mechanical and electrical polarization switching on the prototypical tetragonal ferroelectric PbZr0.2Ti0.8O3 (PZT) thin films. Using different routes for chemical solution derived processing and rapid thermal annealing crystallization of epitaxial PZT thin films, we gain control over the electrical properties, chemistry and microstructure of thin films of different thickness. The ferroelectric properties obtained from microcapacitors underline that polarization switching behaviors under electric field are compatible with out-of-plane c-oriented tetragonal PZT, depicting remnant polarization values close to bulk ones for film thickness above 100 nm. Interestingly, a decrease of measured remnant polarization and larger leakage current are observed in capacitors based on films with thickness below 100 nm as well as in those undergoing different crystallization processes. To understand the nanoscale nature of the ferroelectric properties of these films, we used atomic force microscopy (AFM) derived techniques, i.e. piezoresponse force microscopy and local piezoelectric hysteresis loops [1]. Through application of voltage and/or pressure using the AFM-tip, within different electrical boundary conditions, we studied the nucleation and switching phenomena in as grown and in electrically and pressure-induced patterned ferroelectric domains. Results on the coercive electric fields and threshold forces required for polarization switching of PZT films are analyzed in view not only of the different electrical and mechanical poling, but also on the microstructure, film density, defects and chemical composition determined from X-ray diffraction, scanning electron transmission microscopy and electron energy loss spectroscopy, Rutherford backscattering and secondary ion mass spectroscopies.Polarization switching results of PZT films both at the micro- and nano-scales underline that the robust ferroelectric properties and switching mechanisms arise from reproducible chemistry, (micro)structure and defect distribution over thickness in chemical solution derived PZT films. These results will be discussed in the framework of integrated ferroelectric films for nanomechanical applications

Conditional Probability of Survival and Prognostic Factors in Long-Term Survivors of High-Grade Serous Ovarian Cancer

International audienceObjective: High-grade serous ovarian cancers (HGSOC) are heterogeneous, often diagnosed at an advanced stage, and associated with poor overall survival (OS, 39% at five years). There are few data about the prognostic factors of late relapses in HGSOC patients who survived ≥five years, long-term survivors (LTS). The aim of our study is to assess the probability of survival according to the already survived time from diagnosis. Methods: Data from HGSOC patients treated between 1995 and 2016 were retrospectively collected to estimate the conditional probability of survival (CPS), probability of surviving Y years after diagnosis when the patient had already survived X years, and to determine the LTS prognostic factors. The primary endpoint was OS. Results: 404 patients were included; 120 of them were LTS. Patients were aged 61 years (range: 20–89), WHO performance status 0–1 in 86.9% and 2 in 13.1%, and Fédération Internationale de Gynécologie et d’Obstétrique (FIGO) staging III and IV in 82.7% and 17.3% patients. Breast cancer (BRCA) status was available in 116 patients (33% mutated), including 58 LTS (36% mutated). No macroscopic residual disease was observed in 58.4% patients. First-line platinum-based chemotherapy plus paclitaxel was administered in 80.4% of patients (median: six cycles (range: 1–14)). After a 9 point 3-year follow-up, median OS was four years (95% CI: 3.6–4.5). The CPS at five years after surviving one year was 42.8% (95% CI: 35.3–48.3); it increased to 81.7% (95% CI: 75.5–87.8) after four survived years. Progression-free interval>18 months was the only LTS prognostic factor in the multivariable analysis (hazard ratio (HR) = 0.23; 95% CI: 0.13–0.40; p < 0.001). Conclusion: The CPS provided relevant and encouraging clinical information on the life expectancy of HGSOC patients who already survived a period of time after diagnosis. LTS prognostic factors are useful for clinicians and patients

A multiscale study of the structure, chemistry and ferroelectric properties of epitaxial sol-gel PbZr0.2Ti0.8O3 films for nanomechanical switching

International audiencePolarization switching phenomena in ferroelectrics are complex processes entangled to electronic, chemical and (micro)(nano)structural properties, and intrinsic and extrinsic defects. These phenomena become critical in the framework of ferroelectric nanostructures, e.g. integrated thin films, where interface and surface effects dominate against volume-related properties.Here, we explore the mechanical and electrical polarization switching of ferroelectric thin films of the prototypical tetragonal ferroelectric PbZr0.2Ti0.8O3 (PZT). Using different parameters for sol-gel derived processing and rapid thermal annealing crystallization, we gain control over the electrical properties, chemistry and nanostructure of epitaxial PZT thin films of different thicknesses. The ferroelectric properties determined from microcapacitors indicate that polarization switching under electric field is compatible with out-of-plane c-oriented tetragonal PZT, depicting bulk-like remnant polarization values for films thicker than 100 nm. In capacitors based on films less than 100 nm thick as well as in those undergoing different crystallization processes, a decrease of the measured remnant polarization and the appearance of a leakage current are observed.Piezoresponse force microscopy was used to understand the nanoscale nature of the ferroelectric properties and the polarization switching under different stimuli of these films and environment. Through application of voltage and/or stress using the atomic force microscope tip, and under different electrical boundary conditions, we studied nucleation and switching phenomena in as-grown and in electrically and stress-induced patterned ferroelectric domains. Coercive electric fields and threshold forces required for polarization switching are not only dependent on the conditions of poling, but also on the structure, chemical and electronic properties, and concentration of defects, which we analyzed at different scales using X-ray diffraction and photoemission spectroscopy, scanning electron transmission microscopy, electron energy loss spectroscopy, and Rutherford backscattering and secondary ion mass spectrometry. Phase field simulations of PZT films depicting nanoscale defects support the experimental evidence of the significant contribution of the strain gradient leading to nanomechanical switching.Our results on polarization switching in epitaxial sol-gel derived PZT films will be discussed in the framework of integrated ferroelectric thin films and nanoscale ferroelectric switching for nanomechanical applications in stress sensors