24 research outputs found

    The initial molecular response predicts the deep molecular response but not treatment-free remission maintenance in a real-world chronic myeloid leukemia cohort

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    In chronic myeloid leukemia, the identification of early molecular predictors of stable treatment-free remission (TFR) after tyrosine kinase inhibitor (TKI) discontinuation is challenging. The predictive values of residual disease (BCR::ABL1 quantification) at months 3 and 6 and more recently, BCR::ABL1 transcript halving time (HT) have been described, but no study compared the predictive value of different early parameters. Using a real-world cohort of 408 patients, we compared the performance of the ELTS score, BCR::ABL1 HT, and residual disease at month 3 and 6 to predict the molecular response, achievement of the TKI discontinuation criteria, and TFR maintenance. The performances of BCR::ABL1 HT and residual disease at month 3 were similar. Residual disease at month 6 displayed the best performance for predicting the optimal response (area under the ROC curve between 0.81 and 0.92; cut-off values: 0.11% for MR4 at month 24 and 0.12% for MR4.5 at month 48). Conversely, no early parameter predicted reaching the TKI discontinuation criteria and TFR maintenance. We obtained similar results when patients were divided in subgroups by first-line treatment (imatinib vs second generation TKI, 2G-TKI). We identified a relationship between ELTS score, earlier milestones and TFR maintenance only in the 2G-TKI group. In conclusion, this first comparative study of early therapeutic response parameters showed that they are excellent indicators of TKI efficacy (BCR::ABL1 transcript reduction) and best responders. Conversely, they did not predict the achievement of the TKI discontinuation criteria and TFR maintenance, suggesting that other parameters are involved in TFR maintenance

    Functional study of Metastatic lymph node 51 protein in mRNA metabolism

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    La protĂ©ine MLN51, surexprimĂ©e dans environ 30% des cancers du sein, est un facteur clĂ© du mĂ©tabolisme des ARNm, en tant que membre du complexe de jonction des exons (EJC). Ce graffiti molĂ©culaire est un rĂ©gulateur essentiel de l’expression gĂ©nique de par son implication dans l’épissage, l’export, la traduction, la stabilitĂ© et la dĂ©gradation des ARNm. A l’échelle structurale, l’EJC est organisĂ© autour d’un coeur protĂ©ique avec l’hĂ©licase eIF4A3, MLN51 et l’hĂ©tĂ©rodimĂšre Magoh/Y14. Ce tĂ©tramĂšre sert de plateforme d’ancrage Ă  d’autres facteurs pĂ©riphĂ©riques. Les mĂ©canismes de recrutement du coeur EJC sur l’ARNm ont Ă©tĂ© Ă©lucidĂ©s par des approches biochimiques. Dans ce contexte, nous avons initiĂ© un travail original destinĂ© Ă  mettre en Ă©vidence la localisation cellulaire de l’assemblage du coeur EJC in vivo. L’utilisation de techniques d’imagerie photonique et Ă©lectronique a permis d’établir un lien vĂ©ritable entre la localisation du coeur EJC et l’architecture nuclĂ©aire. Nous avons montrĂ© que la plupart des facteurs EJC sont localisĂ©s et interagissent Ă  la pĂ©riphĂ©rie des speckles nuclĂ©aires, lieux de stockage des facteurs d’épissage. Ces rĂ©gions discrĂštes nuclĂ©aires ont Ă©tĂ© appelĂ©es «perispeckles» et sont des entitĂ©s distinctes des speckles. De maniĂšre intĂ©ressante, la localisation des protĂ©ines coeur coĂŻncide avec celle des ARNm dans les perispeckles et est spatialement reliĂ©e aux sites transcriptionnels. Ces donnĂ©es dĂ©montrent que l’assemblage du coeur EJC a lieu dans le compartiment nuclĂ©aire et dĂ©finissent le perispeckle comme un territoire intermĂ©diaire entre les speckles nuclĂ©aires et sites de transcription oĂč s’opĂšrent des Ă©vĂšnements post-transcriptionnels fondamentaux.The MLN51 protein, overexpressed in around 30% of breast cancers, is a key factor for mRNA metabolism, as a member of the Exon Junction Complex (EJC). The EJC marks the splicing history of an mRNA and influences many stages of its subsequent metabolism: splicing, dynamic cytoplasmic export, efficient and localized translation, quality-control and stability. Structurally, the EJC is organized around a core complex that is formed by four proteins (eIF4A3, MLN51, Magoh, Y14). The core complex serves as a binding platform for more than a dozen peripheral factors. The EJC is not a pre-assembled complex; however, its assembly mode is well described in vitro using recombinant proteins and splicing extracts. Nevertheless, where this complex assembles in vivo was a matter of debate. By using light and electron microscopy approaches, we established an original link between the cellular distribution of the EJC core factors and the nuclear architecture. The core and most of the peripheral EJC factors are colocalized and interact together in discrete regions of the nucleus, located at the periphery of nuclear speckles. This doughnut-shaped region appears to be a novel nuclear territory that we termed “the perispeckle”. This territory is distinct from nuclear speckles; it contains nascent mRNAs and it is close to active transcription sites. Overall, this study supports a model in which the deposition of the EJC core takes place in the nucleus, and that assembled EJC core factors concentrate in discrete subnuclear territories termed perispeckles. These regions contribute to the compartmentalization of the nucleus as an active domain implicated in mRNP packaging

    Functional study of Metastatic lymph node 51 protein in mRNA metabolism

    No full text
    La protĂ©ine MLN51, surexprimĂ©e dans environ 30% des cancers du sein, est un facteur clĂ© du mĂ©tabolisme des ARNm, en tant que membre du complexe de jonction des exons (EJC). Ce graffiti molĂ©culaire est un rĂ©gulateur essentiel de l’expression gĂ©nique de par son implication dans l’épissage, l’export, la traduction, la stabilitĂ© et la dĂ©gradation des ARNm. A l’échelle structurale, l’EJC est organisĂ© autour d’un coeur protĂ©ique avec l’hĂ©licase eIF4A3, MLN51 et l’hĂ©tĂ©rodimĂšre Magoh/Y14. Ce tĂ©tramĂšre sert de plateforme d’ancrage Ă  d’autres facteurs pĂ©riphĂ©riques. Les mĂ©canismes de recrutement du coeur EJC sur l’ARNm ont Ă©tĂ© Ă©lucidĂ©s par des approches biochimiques. Dans ce contexte, nous avons initiĂ© un travail original destinĂ© Ă  mettre en Ă©vidence la localisation cellulaire de l’assemblage du coeur EJC in vivo. L’utilisation de techniques d’imagerie photonique et Ă©lectronique a permis d’établir un lien vĂ©ritable entre la localisation du coeur EJC et l’architecture nuclĂ©aire. Nous avons montrĂ© que la plupart des facteurs EJC sont localisĂ©s et interagissent Ă  la pĂ©riphĂ©rie des speckles nuclĂ©aires, lieux de stockage des facteurs d’épissage. Ces rĂ©gions discrĂštes nuclĂ©aires ont Ă©tĂ© appelĂ©es «perispeckles» et sont des entitĂ©s distinctes des speckles. De maniĂšre intĂ©ressante, la localisation des protĂ©ines coeur coĂŻncide avec celle des ARNm dans les perispeckles et est spatialement reliĂ©e aux sites transcriptionnels. Ces donnĂ©es dĂ©montrent que l’assemblage du coeur EJC a lieu dans le compartiment nuclĂ©aire et dĂ©finissent le perispeckle comme un territoire intermĂ©diaire entre les speckles nuclĂ©aires et sites de transcription oĂč s’opĂšrent des Ă©vĂšnements post-transcriptionnels fondamentaux.The MLN51 protein, overexpressed in around 30% of breast cancers, is a key factor for mRNA metabolism, as a member of the Exon Junction Complex (EJC). The EJC marks the splicing history of an mRNA and influences many stages of its subsequent metabolism: splicing, dynamic cytoplasmic export, efficient and localized translation, quality-control and stability. Structurally, the EJC is organized around a core complex that is formed by four proteins (eIF4A3, MLN51, Magoh, Y14). The core complex serves as a binding platform for more than a dozen peripheral factors. The EJC is not a pre-assembled complex; however, its assembly mode is well described in vitro using recombinant proteins and splicing extracts. Nevertheless, where this complex assembles in vivo was a matter of debate. By using light and electron microscopy approaches, we established an original link between the cellular distribution of the EJC core factors and the nuclear architecture. The core and most of the peripheral EJC factors are colocalized and interact together in discrete regions of the nucleus, located at the periphery of nuclear speckles. This doughnut-shaped region appears to be a novel nuclear territory that we termed “the perispeckle”. This territory is distinct from nuclear speckles; it contains nascent mRNAs and it is close to active transcription sites. Overall, this study supports a model in which the deposition of the EJC core takes place in the nucleus, and that assembled EJC core factors concentrate in discrete subnuclear territories termed perispeckles. These regions contribute to the compartmentalization of the nucleus as an active domain implicated in mRNP packaging

    Etude fonctionnelle de la protéine Metastatic lymph node 51 dans le métabolisme des ARN messagers

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    La protĂ©ine MLN51, surexprimĂ©e dans environ 30% des cancers du sein, est un facteur clĂ© du mĂ©tabolisme des ARNm, en tant que membre du complexe de jonction des exons (EJC). Ce graffiti molĂ©culaire est un rĂ©gulateur essentiel de l expression gĂ©nique de par son implication dans l Ă©pissage, l export, la traduction, la stabilitĂ© et la dĂ©gradation des ARNm. A l Ă©chelle structurale, l EJC est organisĂ© autour d un coeur protĂ©ique avec l hĂ©licase eIF4A3, MLN51 et l hĂ©tĂ©rodimĂšre Magoh/Y14. Ce tĂ©tramĂšre sert de plateforme d ancrage Ă  d autres facteurs pĂ©riphĂ©riques. Les mĂ©canismes de recrutement du coeur EJC sur l ARNm ont Ă©tĂ© Ă©lucidĂ©s par des approches biochimiques. Dans ce contexte, nous avons initiĂ© un travail original destinĂ© Ă  mettre en Ă©vidence la localisation cellulaire de l assemblage du coeur EJC in vivo. L utilisation de techniques d imagerie photonique et Ă©lectronique a permis d Ă©tablir un lien vĂ©ritable entre la localisation du coeur EJC et l architecture nuclĂ©aire. Nous avons montrĂ© que la plupart des facteurs EJC sont localisĂ©s et interagissent Ă  la pĂ©riphĂ©rie des speckles nuclĂ©aires, lieux de stockage des facteurs d Ă©pissage. Ces rĂ©gions discrĂštes nuclĂ©aires ont Ă©tĂ© appelĂ©es perispeckles et sont des entitĂ©s distinctes des speckles. De maniĂšre intĂ©ressante, la localisation des protĂ©ines coeur coĂŻncide avec celle des ARNm dans les perispeckles et est spatialement reliĂ©e aux sites transcriptionnels. Ces donnĂ©es dĂ©montrent que l assemblage du coeur EJC a lieu dans le compartiment nuclĂ©aire et dĂ©finissent le perispeckle comme un territoire intermĂ©diaire entre les speckles nuclĂ©aires et sites de transcription oĂč s opĂšrent des Ă©vĂšnements post-transcriptionnels fondamentaux.The MLN51 protein, overexpressed in around 30% of breast cancers, is a key factor for mRNA metabolism, as a member of the Exon Junction Complex (EJC). The EJC marks the splicing history of an mRNA and influences many stages of its subsequent metabolism: splicing, dynamic cytoplasmic export, efficient and localized translation, quality-control and stability. Structurally, the EJC is organized around a core complex that is formed by four proteins (eIF4A3, MLN51, Magoh, Y14). The core complex serves as a binding platform for more than a dozen peripheral factors. The EJC is not a pre-assembled complex; however, its assembly mode is well described in vitro using recombinant proteins and splicing extracts. Nevertheless, where this complex assembles in vivo was a matter of debate. By using light and electron microscopy approaches, we established an original link between the cellular distribution of the EJC core factors and the nuclear architecture. The core and most of the peripheral EJC factors are colocalized and interact together in discrete regions of the nucleus, located at the periphery of nuclear speckles. This doughnut-shaped region appears to be a novel nuclear territory that we termed the perispeckle . This territory is distinct from nuclear speckles; it contains nascent mRNAs and it is close to active transcription sites. Overall, this study supports a model in which the deposition of the EJC core takes place in the nucleus, and that assembled EJC core factors concentrate in discrete subnuclear territories termed perispeckles. These regions contribute to the compartmentalization of the nucleus as an active domain implicated in mRNP packaging.STRASBOURG-Bib.electronique 063 (674829902) / SudocSudocFranceF

    Cardio-Oncology Preclinical Models: A Comprehensive Review

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    International audienceCardiotoxicity is a common side effect induced by cancer therapies, which increases the risk of long-term morbidity and mortality in cancer survivors. To date, the mechanism leading to this toxicity is still unclear, thus complicating cardiac safety assessment and predictive factor identification. The advances in technology, particularly regarding radiation therapy and constant development of novel antineoplastic agents, require urgent development of efficient preclinical models to detect drug cardiotoxicity. A myriad of empirical preclinical models have been used to investigate cardiotoxicity, though with limited success. Recently, multicellular spheroid models have gained attention by mimicking the in vivo microenvironment. The aim of this review is to focus on the most relevant preclinical models used to assess antineoplastic drug- and radiotherapy-related cardiotoxicities, with an overview on their current use. It also aims to discuss the possible directions of translational research in the cardio-oncology field

    How to improve clinical research in a department of radiation oncology

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    International audienceIntroductionRadiation therapy is a core modality for cancer treatment. Around 40% of cancer cures include the use of radiotherapy, either as a single strategy or combined with other treatments. In the past decade, substantial technical advances and novel insights into radiobiological properties have considerably improved patients’ outcomes. This study overviewed the landscape of clinical research at our radiotherapy department.MethodsWe surveyed our institutional database of clinical trials to collect information for completed or ongoing radiation therapy clinical trials, from 2005 to December 2017 at the Lucien Neuwirth cancer institute.ResultsA total of 31 clinical trials were undertaken during the study period, of which 4 studies (12.9%) were industry-sponsored and 3 studies (9.7%) were launched by our radiotherapy unit. The vast majority of clinical trials (83.9%) were dedicated to unique organ localization, especially urological cancer (prostate or bladder) (42%). We also observed a shift towards more phase II trials during the study period as well as a special focus on elderly population. Over the last decade, the number of included patients increased by a 5.3 fold input, with 135 inclusions before 2011 and 720 inclusions after 2011.DiscussionThis study provided an observational and comprehensive analysis of radiotherapy research. From a monocentric point-of-view, these results reflected the on-going progress of worldwide radiotherapy research. Based on a 13-years’ experience, this study aimed at highlighting essential cues to ensure efficient and perennial researc

    To exploit the 5 ‘R’ of radiobiology and unleash the 3 ‘E’ of immunoediting: ‘RE’-inventing the radiotherapy-immunotherapy combination

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    International audienceHow radiotherapy counters immune evasion In conventional radiotherapy (RT), the relative biologic effectiveness of radiation is influenced by radiobiological determinants, the so-called ‘5Rs’: Repair, Repopulation, Redistribution, Reoxygenation, and Radiosensitivity.1 A linear-quadratic model prevails to describe the radiation response of the tumor, in which the α/ÎČ ratio is used to characterize the sensitivity of a particular tissue type to fractionation. Fractionation serves to decrease acute, and especially late, toxicity to surrounding normal tissue exposed to RT. Commonly, curative RT is delivered in daily doses of 1.8–2.2 Gy for 5–8 weeks, whereas hypofractionation is defined as a delivery of greater than 2.2 Gy per fraction. With sophisticated advances in RT technologies, delivering higher doses of RT per fraction [i.e. increased biologically effective dose (BED)] in a shorter timeframe appears a safe option. Indeed, increased BED could be achieved with larger fraction sizes relative to conventionally fractionated RT. While early radiobiological studies had found that the major mechanisms of action of radiation were related to DNA damage and subsequent cell death of dividing cells, novel insights on radiation effects have uncovered the immunomodulatory properties of ionizing radiation.

    Fulminant hepatitis due to very severe sinusoidal obstruction syndrome (SOS/VOD) after autologous peripheral stem cell transplantation: a case report

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    Abstract Background Hepatic veno-occlusive disease, also called sinusoidal obstruction syndrome (SOS/VOD), is a potentially fatal complication of allogeneic or autologous hematopoietic stem cell transplantation. A plethora of transplant and patient-related risk factors predispose to SOS/VOD and should be taken into account for prognosis assessment as well as for adequate therapeutic intervention. Case presentation We describe the case of a mantle cell lymphoma patient who developed a fulminant hepatitis following oxaliplatin-containing intensive chemotherapy and autologous transplantation. This clinical manifestation was secondary to a very severe SOS/VOD. The patient did not exhibit the usual risk factors and presented a non-classical form with major cytolysis, thus puzzling SOS/VOD diagnosis in this context. Conclusion SOS has been previously reported after oxaliplatin-based chemotherapy regimens for colorectal cancers, in particular in patients with colorectal liver metastases. We therefore suspected a potential relationship with oxaliplatin-based regimen as a driver of SOS/VOD in a non-susceptible lymphoma patient. With regards to this case, clinicians and especially intensivists should be aware of this atypical presentation

    Differential Formation of Stress Granules in Radiosensitive and Radioresistant Head and Neck Squamous Cell Carcinoma Cells

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    International audiencePurpose: Stress granules (SGs) are cytoplasmic aggregates in which mRNAs and specific proteins are trapped in response to a variety of damaging agents. They participate in the cellular defense mechanisms. Currently, their mechanism of formation in response to ionizing radiation and their role in tumor-cell radiosensitivity remain elusive.Methods and materials: The kinetics of SG formation was investigated after the delivery of photon irradiation at different doses to head and neck squamous cell carcinoma cell lines with different radiosensitivities and the HeLa cervical cancer cell line (used as reference). In parallel, the response to a canonical inducer of SGs, sodium arsenite, was also studied. Immunolabeling of SG-specific proteins and mRNA fluorescence in situ hybridization enabled SG detection and quantification. Furthermore, a ribopuromycylation assay was used to assess the cell translational status. To determine whether reactive oxygen species were involved in SG formation, their scavenging or production was induced by pharmacologic pretreatment in both SCC61 and SQ20B cells.Results: Photon irradiation at different doses led to the formation of cytoplasmic foci that were positive for different SG markers. The presence of SGs gradually increased from 30 minutes to 2 hours postexposure in HeLa, SCC61, and Cal60 radiosensitive cells. In turn, the SQ20B and FaDu radioresistant cells did not form SGs. These results indicated a correlation between sensitivity to photon irradiation and SG formation. Moreover, SG formation was significantly reduced by reactive oxygen species scavenging using dimethyl sulfoxide in SCC61 cells, which supported their role in SG formation. However, a reciprocal experiment in SQ20B cells that depleted glutathione using buthionine sulfoximide did not restore SG formation in these cells.Conclusions: SGs are formed in response to irradiation in radiosensitive, but not in radioresistant, head and neck squamous cell carcinoma cells. Interestingly, compared with sodium arsenite-induced SGs, photon-induced SGs exhibited a different morphology and cellular localization. Moreover, photon-induced SGs were not associated with the inhibition of translation; rather, they depended on oxidative stress
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