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BackgroundWhile great advances in clinical and pathological description of tenosynovial giant cell tumors (TGCT) have been made, TGCT molecular heterogeneity represents an ongoing challenge. The canonical oncogenic fusion CSF1::COL6A3 is not systematically observed, suggesting that other oncogenic mechanisms are involved in tumorigenesis. This study aims to explore by RNA sequencing a retrospective series of tumors diagnosed as TGCT, in order to provide a better description of their molecular landscape and to correlate molecular features with clinical data.MethodsWe analyzed clinicopathological data and performed whole-exome RNA sequencing on 41 TGCT samples.ResultsRNAseq analysis showed significant higher CSF1 and CSF1-R expression than a control panel of 2642 solid tumors. RNA sequencing revealed fusion transcripts in 14 patients including 6 not involving CSF1 and some previously unreported fusions. Unsupervised clustering on the expression profiles issued from this series suggested two distinct subgroups: one composed of various molecular subtypes including CSF1 and FN1 rearranged samples and one composed of four tumors harboring an HMGA2::NCOR2 fusion, suggesting distinct tumor entities. Overall, 15 patients received at least one systemic anti-CSF1R treatment and clinical improvement was observed in 11 patients, including patients from both clusters.DiscussionThis study reported molecular heterogeneity in TGCT, contrasting with the clinical and pathological homogeneity and the ubiquitous high CSF1 and CSF1R expression levels. Whether molecular diversity may impact the efficacy of systemic treatments needs to be further investigated.

Introduction A few studies have highlighted the potential synergy between early palliative care and inclusion in an early-phase clinical trial that may improve quality of life, reduce symptoms of exhaustion related to the side effects of treatment and allow patients to complete their treatment protocol. The primary objective of this qualitative study is to evaluate the reasons for acceptance or refusal of early palliative care in patients included in early-phase clinical trials.Method and analysis All patients from the Centre Léon Bérard (Comprehensive Cancer Centre in Lyon, France) who consent to one of the early-phase clinical trials proposed at the centre will be invited to participate in this study. The cohort will consist of a subgroup (n=20) of patients who accept palliative care together with their clinical trial, and a second subgroup (n=20) of patients who decline it. Patients will be interviewed in exploratory interviews conducted by a psychology researcher before the start of their clinical trial. The interviews will be audio-recorded. Patients will also be asked to complete quality of life and anxiety/depression questionnaires both before the beginning of the treatment and at the end of their clinical trial. The content of the interviews will be analysed thematically. Descriptive and comparative statistical analysis of both cohorts will also be conducted.Ethics and dissemination Personal data will be collected and processed in accordance with the laws and regulations in force. All patients will give informed consent to participate. This study complies with reference methodology MR004 of the Commission Nationale de l'Informatique et des Libertés. The protocol has received the validation of an ethics committee (Groupe de Réflexion Ethique du CLB, number: 2020-006). The results will be disseminated through conference presentations and peer-reviewed publications.Trial registration number NCT04717440.

Plants contain several NADPH-producing enzymes including glucose-6-phosphate dehydrogenases (G6PDH) with different sub-cellular localizations. The activity of plastidial G6PDHs is redox-regulated by thioredoxins (TRX). Although specific TRXs are known to regulate chloroplastic isoforms of G6PDH, little information is available for plastidic isoforms found in heterotrophic organs or tissues. Here, we investigated TRX regulation of the two G6PDH plastidic isoforms of Arabidopsis roots during exposure to a mild salt stress. We report that in vitro m-type TRXs are the most efficient regulators of the G6PDH2 and G6PDH3 mainly found in Arabidopsis roots. While expression of the corresponding G6PD and plastidic TRX genes was marginally affected by salt, it impaired root growth of several of the corresponding mutant lines. Using an in situ assay for G6PDH, G6PDH2 was found to be the major contributor to salt-induced increases in activity, while data from ROS assays further provide in vivo evidence that TRX m acts in redox regulation during salt stress. Taken together, our data suggest that regulation of plastid G6PDH activity by TRX m may be an important player regulating NADPH production in Arabidopsis roots undergoing salt stress.

Background: Advanced sarcoma is a group of heterogeneous disease with poor prognosis and poor efficacy of medical treatment. They represent a promising group of tumors to assess molecular-based therapy (MBT) strategy. Patients and methods: Genomic profiles of patients with advanced sarcoma included in the ProfiLER program were established by NGS using a 69 genes panel and CGH array. A weekly molecular board reviewed genomic reports to select relevant genomic alterations and propose recommendations for MBT. Results: A genomic profile was available for 158 of 164 patients. At least 1 relevant genomic alteration was reported for 106 patients (67%), with frequent multiple alterations (68%). In total, 289 relevant genomic alterations were identified in 143 different genes; 139 homozygous deletions, 86 gene amplifications and 64 somatic mutations. The most frequently impacted genes were TP53, Rb1, CDKN2A, CDK4, MDM2, and PTEN. MBT was recommended for 47 patients and initiated for 13 patients.One objective response was observed for an angiosarcoma treated with pazopanib for FLT4 amplification; 4 patients had a stable disease, including a long-lasting 33 months stabilization. Conclusion: Genomic profiling for advanced sarcoma is feasible, even for bone sarcoma. A small proportion of patients are eventually treated with MBT, similar to other tumor types. We could not demonstrate this strategy to be beneficial to patients. Our data suggest that molecular profiling should not be used in routine practice but warrants further exploration in clinical trials, focusing on sarcoma with complex genomic, and adding transcriptomic analysis to the copy number and mutational analyses.

Thioredoxins (TRXs) are key players within the complex response network of plants to environmental constraints. Here, the physiological implication of the plastidial y-type TRXs in Arabidopsis drought tolerance was examined. We previously showed that TRXs y1 and y2 have antioxidant functions, and here, the corresponding single and double mutant plants were studied in the context of water deprivation. TRX y mutant plants showed reduced stress tolerance in comparison with wild-type (WT) plants that correlated with an increase in their global protein oxidation levels. Furthermore, at the level of the main antioxidant metabolites, while glutathione pool size and redox state were similarly affected by drought stress in WT and trxy1y2 plants, ascorbate (AsA) became more quickly and strongly oxidized in mutant leaves. Monodehydroascorbate (MDA) is the primary product of AsA oxidation and NAD(P)H-MDA reductase (MDHAR) ensures its reduction. We found that the extractable leaf NADPH-dependent MDHAR activity was strongly activated by TRX y2. Moreover, activity of recombinant plastid Arabidopsis MDHAR isoform (MDHAR6) was specifically increased by reduced TRX y, and not by other plastidial TRXs. Overall, these results reveal a new function for y-type TRXs and highlight their role as major antioxidants in plastids and their importance in plant stress tolerance.