Apoptose et voie WNT/beta -caténine (induction et régulation par le monoxyde d azote dans des cellules cancéreuses coliques humaines)

Les cancers sont le plus souvent la conséquence d une perturbation de l équilibre entre la vie et la mort cellulaire. Ainsi, tout agent cytotoxique capable d intervenir sur ces processus est potentiellement utilisable dans le traitement des cancers. Nous avons démontré, que le GTN (GlycerylTriNitrate), un donneur endogène de monoxyde d azote (NO), induit l apoptose des cellules cancéreuses coliques humaines de manière dépendante des caspases-1 et -10 et les sensibilise à l apoptose induite par le ligand de Fas. Nous avons également analysé les effets du GTN sur la voie de signalisation Wnt/beta caténine impliquée dans la survenue des cancers colorectaux. J ai démontré que le GTN diminue très fortement l activité de cette voie en activant une enzyme sensible aux inhibiteurs de sérine protéases, TPCK et AEBSF. Nous avons ainsi mis en évidence un mécanisme original de régulation de la voie Wnt/ beta caténine qui s ajoute à ceux impliquant le protéasome, les caspases ou encore les calpaïnes.Deregulation of signaling pathways involved in survival or cell death is the leading cause of cancer. Therefore, any cytotoxic agent able to modulate these pathways is potentially efficient in cancer treatment. We demonstrate that, glyceryltrinitrate (GTN), an endogenous nitric oxide (NO) donor, induces caspase-1 and -10-dependant human colon cancer cells apoptosis. Moreover, GTN sensitizes these cells to Fas ligand induced apoptosis. We also analyze GTN effects on the oncogenic signaling Wnt/ beta catenin pathway which is highly active in colorectal cancer. I demonstrate that GTN induces a strong decrease of this activity mediated by an enzyme sensitive to two serine protease inhibitors, TPCK and AEBSF. Therefore, we describe an original regulatory mechanism of the Wnt/ beta catenin pathway additionally to proteasome, calpain or caspase degradation pathways.DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF

Influence of the nitric oxide donor glyceryl trinitrate on apoptotic pathways in human colon cancer cells

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Safety and pharmacokinetics of Roscovitine (Seliciclib) in cystic fibrosis patients chronically infected with Pseudomonas aeruginosa, a randomized, placebo-controlled study

International audienceBackground: The orally available kinase inhibitor R-roscovitine has undergone clinical trials against various cancers and is currently under clinical evaluation against Cushing disease and rheumatoid arthritis. Roscovitine displays biological properties suggesting potential benefits in CF: it partially corrects F508del-CFTR trafficking, stimulates the bactericidal properties of CF alveolar macrophages, and displays anti-inflammatory properties and analgesic effects.Methods: A phase 2 trial study (ROSCO-CF) was launched to evaluate the safety and effects of roscovitine in Pseudomonas aeruginosa infected adult CF patients carrying two CF causing mutations (at least one F508del-CFTR mutation) and harboring a FEV1 ≥40%. ROSCO-CF was a multicenter, double-blind, placebo-controlled, dose-ranging study (200, 400, 800 mg roscovitine, orally administered daily for 4 days/week/4 weeks).Results: Among the 34 volunteers enrolled, randomization assigned 11/8/8/7 to receive the 0 (placebo)/ 200/400/800 mg roscovitine doses, respectively. In these subjects with polypharmacy, roscovitine was relatively safe and well-tolerated, with no significant adverse effects (AEs) other than five serious AEs (SAEs) possibly related to roscovitine. Pharmacokinetics of roscovitine were rather variable among subjects. No significant efficacy, at the levels of inflammation, infection, spirometry, sweat chloride, pain and quality of life, was detected in roscovitine-treated groups compared to the placebo-treated group.Conclusion: Roscovitine was relatively safe and well-tolerated in CF patients especially at the 200 and 400 mg doses. However, there were 5 subject withdrawals due to SAEs in the roscovitine group and none in the placebo group. The lack of evidence for efficacy of roscovitine (despite encouraging cellular and animal results) may be due to high pharmacokinetics variability, short duration of treatment, and/or inappropriate dosing protocol

Clinical response to lumacaftor-ivacaftor in patients with cystic fibrosis according to baseline lung function

International audienceBackground: Phase 3 trials have demonstrated the safety and efficacy of lumacaftor-ivacaftor (LUMA-IVA) in patients with cystic fibrosis (CF) homozygous for the Phe508del CFTR mutation and percent predicted forced expiratory volume in 1 s (ppFEV1) between 40 and 90. Marketing authorizations have been granted for patients at all levels of ppFEV1.Methods: To evaluate the safety and effectiveness of LUMA-IVA over the first year of treatment in patients with ppFEV1<40 or ppFEV1≥90 in comparison with those with ppFEV1 [40-90[. Analysis of data collected during a real world study, which included all patients aged ≥12 years who started LUMA-IVA in 2016 across all 47 French CF centers.Results: 827 patients were classified into 3 subgroups according to ppFEV1 at treatment initiation (ppFEV1<40, n = 121; ppFEV1 [40-90[, n = 609; ppFEV1≥90, n = 97). Treatment discontinuation rate was higher in ppFEV1<40 patients (28.9%) than in those with ppFEV1 [40-90[(16.4%) or ppFEV1≥90 (17.5%). In patients with uninterrupted treatment, significant increase in ppFEV1 occurred in the ppFEV1 [40-90[subgroup (+2.9%, P<0.001), and in those ppFEV1<40 (+0.5%, P = 0.03) but not in those with ppFEV1≥90 (P = 0.46). Compared with the year prior to initiation, the number of days of intravenous antibiotics were reduced in all subgroups, although 72% of patients with ppFEV1<40 still experienced at least one exacerbation/year under LUMA-IVA. Comparable increase in body mass index was seen in the three subgroups.Conclusion: Phe508del homozygous CF patients benefit from LUMA-IVA at all levels of baseline lung function, but the characteristics and magnitude of the response vary depending on ppFEV1 at baseline

CT Imaging Assessment of Response to Treatment in Allergic Bronchopulmonary Aspergillosis in Adults With Bronchial Asthma

International audienceBackgroundOne of the major challenges in managing allergic bronchopulmonary aspergillosis (ABPA) remains consistent and reproducible assessment of response to treatment.Research questionWhat are the most relevant changes in computed tomography (CT-scan) parameters over time for assessing response to treatment?Study Design and MethodsIn this ancillary study of a randomized clinical trial (NEBULAMB), asthmatic patients with available CT-scan and without exacerbation during a 4-month ABPA exacerbation treatment period (corticosteroids and itraconazole) were included. Changed CT-scan parameters were assessed by systematic analyses of CT-scan findings at initiation (M0) and end of treatment (M4). CT-scans were assessed by two radiologists blinded to the clinical data. Radiological parameters were determined by selecting those showing significant changes over time. Improvement of at least one, without worsening of the others, defined the radiological response. Agreement between radiological changes, clinical and immunologic responses was likewise investigated.ResultsAmong the 139 originally randomized patients, 132 were included. We identified 5 CT-scan parameters showing significant changes at M4: mucoid impaction extent, mucoid impaction density, centrilobular micronodules, consolidation/ground-glass opacities and bronchial wall thickening (P<0.05). These changes were only weakly associated with one another, except for mucoid impaction extent and density. No agreement was observed between clinical or immunologic and radiological responses, assessed as an overall response, or considering each of the parameters (Cohen’s κ, -0.01 to 0.24).InterpretationChanges in extent and density of mucoid impactions, centrilobular micronodules, consolidation/ground-glass opacities and thickening of the bronchial walls were found to be the most relevant CT-scan parameters to assess radiological response to treatment. A clinical, immunologic and radiological multidimensional approach should be adopted to assess outcomes, probably with a composite definition of response to treatment

Rapid Improvement after Starting Elexacaftor–Tezacaftor–Ivacaftor in Patients with Cystic Fibrosis and Advanced Pulmonary Disease

International audienceRationale: Elexacaftor-tezacaftor-ivacaftor is a CFTR (cystic fibrosis [CF] transmembrane conductance regulator) modulator combination, developed for patients with CF with at least one Phe508del mutation. Objectives: To evaluate the effects of elexacaftor-tezacaftor- ivacaftor in patients with CF and advanced respiratory disease. Methods: A prospective observational study, including all patients aged ⩾12 years and with a percent-predicted FEV1 (ppFEV1) <40 who initiated elexacaftor-tezacaftor-ivacaftor from December 2019 to August 2020 in France was conducted. Clinical characteristics were collected at initiation and at 1 and 3 months. Safety and effectiveness were evaluated by September 2020. National-level transplantation and mortality figures for 2020 were obtained from the French CF and transplant centers and registries. Measurements and Main Results: Elexacaftor-tezacaftor- ivacaftor was initiated in 245 patients with a median (interquartile range) ppFEV1 = 29 (24-34). The mean (95% confidence interval) absolute increase in the ppFEV1 was +15.1 (+13.8 to +16.4; P < 0.0001), and the mean (95% confidence interval) in weight was +4.2 kg (+3.9 to +4.6; P < 0.0001). The number of patients requiring long-term oxygen, noninvasive ventilation, and/or enteral tube feeding decreased by 50%, 30%, and 50%, respectively (P < 0.01). Although 16 patients were on the transplant waiting list and 37 were undergoing transplantation evaluation at treatment initiation, only 2 received a transplant, and 1 died. By September 2020, only five patients were still on the transplantation path. Compared with the previous 2 years, a twofold decrease in the number of lung transplantations in patients with CF was observed in 2020, whereas the number of deaths without transplantation remained stable. Conclusions: In patients with advanced disease, elexacaftor-tezacaftor-ivacaftor is associated with rapid clinical improvement, often leading to the indication for lung transplantation being suspended