43 research outputs found
Early T Cell Signalling Is Reversibly Altered in PD-1+ T Lymphocytes Infiltrating Human Tumors
To improve cancer immunotherapy, a better understanding of the weak efficiency of tumor-infiltrating T lymphocytes (TIL) is necessary. We have analyzed the functional state of human TIL immediately after resection of three types of tumors (NSCLC, melanoma and RCC). Several signalling pathways (calcium, phosphorylation of ERK and Akt) and cytokine secretion are affected to different extents in TIL, and show a partial spontaneous recovery within a few hours in culture. The global result is an anergy that is quite distinct from clonal anergy induced in vitro, and closer to adaptive tolerance in mice. PD-1 (programmed death -1) is systematically expressed by TIL and may contribute to their anergy by its mere expression, and not only when it interacts with its ligands PD-L1 or PD-L2, which are not expressed by every tumor. Indeed, the TCR-induced calcium and ERK responses were reduced in peripheral blood T cells transfected with PD-1. Inhibition by sodium stibogluconate of the SHP-1 and SHP-2 phosphatases that associate with several inhibitory receptors including PD-1, relieves part of the anergy apparent in TIL or in PD-1-transfected T cells. This work highlights some of the molecular modifications contributing to functional defects of human TIL
Development and validation of a rabbit model of Pseudomonas aeruginosa non-ventilated pneumonia for preclinical drug development
BackgroundNew drugs targeting antimicrobial resistant pathogens, including Pseudomonas aeruginosa, have been challenging to evaluate in clinical trials, particularly for the non-ventilated hospital-acquired pneumonia and ventilator-associated pneumonia indications. Development of new antibacterial drugs is facilitated by preclinical animal models that could predict clinical efficacy in patients with these infections.MethodsWe report here an FDA-funded study to develop a rabbit model of non-ventilated pneumonia with Pseudomonas aeruginosa by determining the extent to which the natural history of animal disease reproduced human pathophysiology and conducting validation studies to evaluate whether humanized dosing regimens of two antibiotics, meropenem and tobramycin, can halt or reverse disease progression.ResultsIn a rabbit model of non-ventilated pneumonia, endobronchial challenge with live P. aeruginosa strain 6206, but not with UV-killed Pa6206, caused acute respiratory distress syndrome, as evidenced by acute lung inflammation, pulmonary edema, hemorrhage, severe hypoxemia, hyperlactatemia, neutropenia, thrombocytopenia, and hypoglycemia, which preceded respiratory failure and death. Pa6206 increased >100-fold in the lungs and then disseminated from there to infect distal organs, including spleen and kidneys. At 5 h post-infection, 67% of Pa6206-challenged rabbits had PaO2 <60 mmHg, corresponding to a clinical cut-off when oxygen therapy would be required. When administered at 5 h post-infection, humanized dosing regimens of tobramycin and meropenem reduced mortality to 17-33%, compared to 100% for saline-treated rabbits (P<0.001 by log-rank tests). For meropenem which exhibits time-dependent bactericidal activity, rabbits treated with a humanized meropenem dosing regimen of 80 mg/kg q2h for 24 h achieved 100% T>MIC, resulting in 75% microbiological clearance rate of Pa6206 from the lungs. For tobramycin which exhibits concentration-dependent killing, rabbits treated with a humanized tobramycin dosing regimen of 8 mg/kg q8h for 24 h achieved Cmax/MIC of 9.8 ± 1.4 at 60 min post-dose, resulting in 50% lung microbiological clearance rate. In contrast, rabbits treated with a single tobramycin dose of 2.5 mg/kg had Cmax/MIC of 7.8 ± 0.8 and 8% (1/12) microbiological clearance rate, indicating that this rabbit model can detect dose-response effects.ConclusionThe rabbit model may be used to help predict clinical efficacy of new antibacterial drugs for the treatment of non-ventilated P. aeruginosa pneumonia
Altérations génomiques récurrentes des sarcomes de l'adulte à génomique complexe (perte d'expression de PTEN et DKK1, mécanismes et implications biologiques)
PARIS5-BU Méd.Cochin (751142101) / SudocSudocFranceF
Cibles thérapeutiques potentielles dans le carcinome épidermoïde de l'oesophage (expression et corrélations pronostiques de EGFR, HER2, CD117, VEGF et p53 sur une série de 126 cas)
BREST-BU Médecine-Odontologie (290192102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
HPV-circulating tumoural DNA by droplet-based digital polymerase chain reaction, a new molecular tool for early detection of HPV metastatic anal cancer? A case report
International audienceno abstrac
Toxicité pulmonaire des inhibiteurs de mTOR. Comparaison de deux populations distinctes : les transplantés d'organe solide et les patients atteints de cancer RESUME
International audienceIntroduction: Mammalian target of rapamycin (mTOR) inhibitors-associated pneumonitis (mTOR-IP) has long been described in solid organ recipients (T) patients but more recently in cancer (K) patients. Its overall characteristics have never been compared between these 2 populations. The aim of this study was to compare them in terms of presentation, severity and outcome in T and in K patients.Material and methods: We carried out a retrospective study in a single French tertiary center. Four databases were used to ensure the exhaustive collection of all mTOR-IP cases between 2001 and 2020. All clinical, biological, radiological, pathological and outcome data were reviewed.Results: Thirty-nine patients with mTOR-IP were diagnosed during this period, 24T and 15K patients. The average dosage of everolimus and sirolimus was 2,65mg (±1,78) and 2,75mg (±0,96) in T patients, respectively, versus 8,75mg (±2,26) for everolimus in K patients. The overall prevalence of mTOR-IP was 6.4% with a median time of occurrence of 7 months [IQR 3-35 months]. mTOR-IP were significantly more frequent (P<0.001) and occurred earlier (P<0.001) in cancer patients. No clinical, functional, radiological, pathological nor outcome differences were otherwise observed between the 2 groups. Average everolimus blood levels at the time of mTOR-IP diagnosis were in the range of recommended therapeutic values.Conclusion: Our study shows that mTOR-IP is comparable in terms of presentation in T and in K patients but that it occurs significantly earlier after drug introduction in the latter. This raises questions as to the potential role of the higher doses used in K patients as well as that of co-treatments in the pathogeny of the disease.Introduction : Les inhibiteurs de mTOR (mammalian target of rapamycin), initialement utilisés comme immunosuppresseurs en transplantation d’organe solide, ont vu leurs indications s’étendre au domaine de l’oncologie médicale en raison de leurs propriétés antitumorales. La toxicité pulmonaire des inhibiteurs de mTOR est rapportée dans les deux indications, mais peu d’études ont exploré les différences entre les pneumopathies aux inhibiteurs de mTOR (mTOR-PI) en transplantation (T) et en oncologie (K). L’objectif de notre étude est de comparer les mTOR-PI dans ces deux populations. Méthodes : Notre étude rétrospective monocentrique a été réalisée dans un centre expert en pneumopathies interstitielles, en transplantation et en oncologie (Hôpital Européen Georges Pompidou). Quatre bases de données ont été utilisées afin d'assurer la collecte exhaustive de tous les cas de mTOR-PI entre 2001 et 2020. Toutes les données cliniques, biologiques, radiologiques et pathologiques ainsi que les résultats ont été collectés et analysés.Résultats: Trente-neuf patients atteints de mTOR-PI ont été diagnostiqués pendant cette période, 24 en transplantation (T) et 15 en oncologie (K). La posologie moyenne de l’everolimus et du sirolimusétait respectivement de 2,65 mg (± 1,78) et 2,75mg (± 0,96) en T contre 8,75mg (± 2,26) pour l’everolimus en K. La prévalence globale de mTOR-PI était de 6,4 % avec un délai médian de survenue de 7 mois [IQR 3-35 mois]. Les mTOR-PI étaient significativement plus fréquentes (p < 0,001) et survenaient plus précocement (p < 0,001) chez les patients K. Aucune autre différence clinique, fonctionnelle, radiologique, pathologique ou de sévérité n'a été observée entre les deux groupes. Au moment du diagnostic de mTOR-PI, 14/18 (78%) des patients transplantés avaient un taux résiduel d’éverolimus dans les normes des valeurs thérapeutiques recommandées.Conclusion: Les pneumopathies aux inhibiteurs de mTOR sont comparables en termes de présentation chez les patients T et K, mais elles surviennent significativement plus tôt après l'introduction du médicament chez ces derniers. Cela pourrait être en partie lié aux différences de posologie utilisées dans ces deux populations
Best imaging signs identified by radiomics could outperform the model: application to differentiating lung carcinoid tumors from atypical hamartomas
Abstract Objectives Lung carcinoids and atypical hamartomas may be difficult to differentiate but require different treatment. The aim was to differentiate these tumors using contrast-enhanced CT semantic and radiomics criteria. Methods Between November 2009 and June 2020, consecutives patient operated for hamartomas or carcinoids with contrast-enhanced chest-CT were retrospectively reviewed. Semantic criteria were recorded and radiomics features were extracted from 3D segmentations using Pyradiomics. Reproducible and non-redundant radiomics features were used to training a random forest algorithm with cross-validation. A validation-set from another institution was used to evaluate of the radiomics signature, the 3D ‘median’ attenuation feature (3D-median) alone and the mean value from 2D-ROIs. Results Seventy-three patients (median 58 years [43‒70]) were analyzed (16 hamartomas; 57 carcinoids). The radiomics signature predicted hamartomas vs carcinoids on the external dataset (22 hamartomas; 32 carcinoids) with an AUC = 0.76. The 3D-median was the most important in the model. Density thresholds 60 HU to predict carcinoids were chosen for their high specificity > 0.90. On the external dataset, sensitivity and specificity of the 3D-median and 2D-ROIs were, respectively, 0.23, 1.00 and 0.13, 1.00 60 HU. The 3D-median was more reproducible than 2D-ROIs (ICC = 0.97 95% CI [0.95‒0.99]; bias: 3 ± 7 HU limits of agreement (LoA) [− 10‒16] vs. ICC = 0.90 95% CI [0.85‒0.94]; bias: − 0.7 ± 21 HU LoA [− 4‒40], respectively). Conclusions A radiomics signature can distinguish hamartomas from carcinoids with an AUC = 0.76. Median density 60 HU on 3D or 2D-ROIs may be useful in clinical practice to diagnose these tumors with confidence, but 3D is more reproducible. Critical relevance statement Radiomic features help to identify the most discriminating imaging signs using random forest. ‘Median’ attenuation value (Hounsfield units), extracted from 3D-segmentations on contrast-enhanced chest-CTs, could distinguish carcinoids from atypical hamartomas (AUC = 0.85), was reproducible (ICC = 0.97), and generalized to an external dataset. Key points • 3D-‘Median’ was the best feature to differentiate carcinoids from atypical hamartomas (AUC = 0.85). • 3D-‘Median’ feature is reproducible (ICC = 0.97) and was generalized to an external dataset. • Radiomics signature from 3D-segmentations differentiated carcinoids from atypical hamartomas with an AUC = 0.76. • 2D-ROI value reached similar performance to 3D-‘median’ but was less reproducible (ICC = 0.90). Graphical Abstrac
Base-Position Error Rate Analysis of Next-Generation Sequencing Applied to Circulating Tumor DNA in Non-Small Cell Lung Cancer: A Prospective Study
International audienceBACKGROUND:Circulating tumor DNA (ctDNA) is an approved noninvasive biomarker to test for the presence of EGFR mutations at diagnosis or recurrence of lung cancer. However, studies evaluating ctDNA as a noninvasive "real-time" biomarker to provide prognostic and predictive information in treatment monitoring have given inconsistent results, mainly due to methodological differences. We have recently validated a next-generation sequencing (NGS) approach to detect ctDNA. Using this new approach, we evaluated the clinical usefulness of ctDNA monitoring in a prospective observational series of patients with non-small cell lung cancer (NSCLC).METHODS AND FINDINGS:We recruited 124 patients with newly diagnosed advanced NSCLC for ctDNA monitoring. The primary objective was to analyze the prognostic value of baseline ctDNA on overall survival. ctDNA was assessed by ultra-deep targeted NGS using our dedicated variant caller algorithm. Common mutations were validated by digital PCR. Out of the 109 patients with at least one follow-up marker mutation, plasma samples were contributive at baseline (n = 105), at first evaluation (n = 85), and at tumor progression (n = 66). We found that the presence of ctDNA at baseline was an independent marker of poor prognosis, with a median overall survival of 13.6 versus 21.5 mo (adjusted hazard ratio [HR] 1.82, 95% CI 1.01-3.55, p = 0.045) and a median progression-free survival of 4.9 versus 10.4 mo (adjusted HR 2.14, 95% CI 1.30-3.67, p = 0.002). It was also related to the presence of bone and liver metastasis. At first evaluation (E1) after treatment initiation, residual ctDNA was an early predictor of treatment benefit as judged by best radiological response and progression-free survival. Finally, negative ctDNA at E1 was associated with overall survival independently of Response Evaluation Criteria in Solid Tumors (RECIST) (HR 3.27, 95% CI 1.66-6.40, p < 0.001). Study population heterogeneity, over-representation of EGFR-mutated patients, and heterogeneous treatment types might limit the conclusions of this study, which require future validation in independent populations.CONCLUSIONS:In this study of patients with newly diagnosed NSCLC, we found that ctDNA detection using targeted NGS was associated with poor prognosis. The heterogeneity of lung cancer molecular alterations, particularly at time of progression, impairs the ability of individual gene testing to accurately detect ctDNA in unselected patients. Further investigations are needed to evaluate the clinical impact of earlier evaluation times at 1 or 2 wk. Supporting clinical decisions, such as early treatment switching based on ctDNA positivity at first evaluation, will require dedicated interventional studies