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Laurent Meijer - One of the best experts on this subject based on the ideXlab platform.
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r Roscovitine and cftr modulators enhance killing of multi drug resistant burkholderia cenocepacia by cystic fibrosis macrophages
Scientific Reports, 2020Co-Authors: Chandra L Shrestha, Laurent Meijer, Jonathan Elie, Shuzhong Zhang, Benjamin L Wisniewski, Stephanie Hafner, Benjamin T KoppAbstract:Cystic fibrosis (CF) is characterized by chronic bacterial infections and heightened inflammation. Widespread ineffective antibiotic use has led to increased isolation of drug resistant bacterial strains from respiratory samples. (R)-Roscovitine (Seliciclib) is a unique drug that has many benefits in CF studies. We sought to determine Roscovitine's impact on macrophage function and killing of multi-drug resistant bacteria. Human blood monocytes were isolated from CF (F508del/F508del) and non-CF persons and derived into macrophages (MDMs). MDMs were infected with CF clinical isolates of B. cenocepacia and P. aeruginosa. MDMs were treated with (R)-Roscovitine or its main hepatic metabolite (M3). Macrophage responses to infection and subsequent treatment were determined. (R)-Roscovitine and M3 significantly increased killing of B. cenocepacia and P. aeruginosa in CF MDMs in a dose-dependent manner. (R)-Roscovitine-mediated effects were partially dependent on CFTR and the TRPC6 channel. (R)-Roscovitine-mediated killing of B. cenocepacia was enhanced by combination with the CFTR modulator tezacaftor/ivacaftor and/or the alternative CFTR modulator cysteamine. (R)-Roscovitine also increased MDM CFTR function compared to tezacaftor/ivacaftor treatment alone. (R)-Roscovitine increases CF macrophage-mediated killing of antibiotic-resistant bacteria. (R)-Roscovitine also enhances other macrophage functions including CFTR-mediated ion efflux. Effects of (R)-Roscovitine are greatest when combined with CFTR modulators or cysteamine, justifying further clinical testing of (R)-Roscovitine or optimized derivatives.
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non linear pharmacokinetics of oral Roscovitine seliciclib in cystic fibrosis patients chronically infected with pseudomonas aeruginosa a study on population pharmacokinetics with monte carlo simulations
Pharmaceutics, 2020Co-Authors: Cyril Leven, Laurent Meijer, Emmanuel Nowak, Sacha Schutz, Mariepierre Audrezet, Tristan MontierAbstract:Roscovitine (Seliciclib), a new protein kinase inhibitor, was administered orally to adult patients with cystic fibrosis for the first time in the ROSCO-CF trial, a dose-escalation, phase IIa, randomized, controlled trial. Extensive pharmacokinetic sampling was performed up to 12 h after the first oral dose. Roscovitine and its main metabolite M3 were quantified by liquid chromatography coupled with tandem mass spectrometry. The pharmacokinetics analyses were performed by non-linear mixed effects modelling. Monte Carlo simulations were performed to assess the impact of dose on the pharmacokinetics of oral Roscovitine. Twenty-three patients received oral doses ranging from 200 to 800 mg of Roscovitine and 138 data points were available for both Roscovitine and M3 concentrations. The pharmacokinetics was best described by a two-compartment parent-metabolite model, with a complex saturable absorption process modelled as the sum of Gaussian inverse density functions. The Monte Carlo simulations showed a dose-dependent and saturable first-pass effect leading to pre-systemic formation of M3. The treatment with proton-pump inhibitors reduced the rate of absorption of oral Roscovitine. The pharmacokinetics of oral Roscovitine in adult patients with cystic fibrosis was non-linear and showed significant inter-individual variability. A repeat-dose study will be required to assess the inter-occasional variability of its pharmacokinetics.
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structural analogues of Roscovitine rescue the intracellular traffic and the function of er retained abcb4 variants in cell models
Scientific Reports, 2019Co-Authors: Virginie Vauthier, Nassima Oumata, Jeanlouis Delaunay, Alix Bruneau, Annemarie Durandschneider, Tounsia Aitslimane, C Housset, Amel Ben Saad, Jonathan Elie, Laurent MeijerAbstract:Adenosine triphosphate binding cassette transporter, subfamily B member 4 (ABCB4) is the transporter of phosphatidylcholine at the canalicular membrane of hepatocytes. ABCB4 deficiency, due to genetic variations, is responsible for progressive familial intrahepatic cholestasis type 3 (PFIC3) and other rare biliary diseases. Roscovitine is a molecule in clinical trial that was shown to correct the F508del variant of cystic fibrosis transmembrane conductance regulator (CFTR), another ABC transporter. In the present study, we hypothesized that Roscovitine could act as a corrector of ABCB4 traffic-defective variants. Using HEK and HepG2 cells, we showed that Roscovitine corrected the traffic and localisation at the plasma membrane of ABCB4-I541F, a prototypical intracellularly retained variant. However, Roscovitine caused cytotoxicity, which urged us to synthesize non-toxic structural analogues. Roscovitine analogues were able to correct the intracellular traffic of ABCB4-I541F in HepG2 cells. Importantly, the phospholipid secretion activity of this variant was substantially rescued by three analogues (MRT2-235, MRT2-237 and MRT2-243) in HEK cells. We showed that these analogues also triggered the rescue of intracellular traffic and function of two other intracellularly retained ABCB4 variants, i.e. I490T and L556R. Our results indicate that structural analogues of Roscovitine can rescue genetic variations altering the intracellular traffic of ABCB4 and should be considered as therapeutic means for severe biliary diseases caused by this class of variations.
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modulating innate and adaptive immunity by r Roscovitine potential therapeutic opportunity in cystic fibrosis
Journal of Innate Immunity, 2016Co-Authors: Laurent Meijer, Deborah J. Nelson, Vladimir Riazanski, Nadège Loaëc, Nassima Oumata, Hervé Galons, Aida G Gabdoulkhakova, Genevieve Heryarnaud, Rozenn Le Berre, Emmanuel NowakAbstract:(R)-Roscovitine, a pharmacological inhibitor of kinases, is currently in phase II clinical trial as a drug candidate for the treatment of cancers, Cushing's disease and rheumatoid arthritis. We here review the data that support the investigation of (R)-Roscovitine as a potential therapeutic agent for the treatment of cystic fibrosis (CF). (R)-Roscovitine displays four independent properties that may favorably combine against CF: (1) it partially protects F508del-CFTR from proteolytic degradation and favors its trafficking to the plasma membrane; (2) by increasing membrane targeting of the TRPC6 ion channel, it rescues acidification in phagolysosomes of CF alveolar macrophages (which show abnormally high pH) and consequently restores their bactericidal activity; (3) its effects on neutrophils (induction of apoptosis), eosinophils (inhibition of degranulation/induction of apoptosis) and lymphocytes (modification of the Th17/Treg balance in favor of the differentiation of anti-inflammatory lymphocytes and reduced production of various interleukins, notably IL-17A) contribute to the resolution of inflammation and restoration of innate immunity, and (4) Roscovitine displays analgesic properties in animal pain models. The fact that (R)-Roscovitine has undergone extensive preclinical safety/pharmacology studies, and phase I and II clinical trials in cancer patients, encourages its repurposing as a CF drug candidate.
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134 Rationale for evaluating (R)-Roscovitine (Seliciclib) in patients with cystic fibrosis
Journal of Cystic Fibrosis, 2015Co-Authors: Laurent Meijer, Deborah J. Nelson, Vladimir Riazanski, A.g. Gabdulkhakova, G. Héry-arnaud, R. Le Berre, Nadège Loaëc, Nassima Oumata, Hervé Galons, Emmanuel NowakAbstract:Objectives (R)-Roscovitine, an inhibitor of cyclin-dependent kinases, is currently under clinical evaluation as a drug candidate against various cancers, Cushing disease and rheumatoid arthritis. Roscovitine has diverse biological properties that could be potentially beneficial in the treatment of CF. Results 1Roscovitine acts as a proteostasis regulator that corrects the trafficking of ΔF508-CFTR. 2Roscovitine improves the bactericidal properties of macrophages from CF patients, by affecting the TRPC6 calcium channel (independently of the CFTR mutation) and by lowering the intraphagolysosomal pH that is abnormally elevated in CF macrophages. 3Its main metabolite also shows a ΔF508-CFTR ‘corrector' effect and biological activity on macrophages, despite lack of kinase inhibitory effects. 4Roscovitine has an anti-inflammatory effect likely originating from its ability to promote neutrophil apoptosis. 5Roscovitine reduces eosinophil degranulation and promotes apoptosis. 6Roscovitine suppresses CD4+ T helper cells differentiation into Th17 (pro-inflammatory lymphocytes) and promotes their differentiation into Tregs (anti-inflammatory lymphocytes). 7Roscovitine is an orally available drug which has undergone preclinical pharmacological and toxicological studies, extensive phase I and II clinical trials, in particular against lung cancer. Conclusion Altogether these data suggest that repurposing Roscovitine for CF is a therapeutically and economically valid proposal. We will present the first clinical protocol designed to validate safety and potential beneficial effects of Roscovitine in CF patients with chronic lung Pseudomonas aeruginosa infection.
Keith S Elmslie - One of the best experts on this subject based on the ideXlab platform.
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Roscovitine binds to novel l channel cav1 2 sites that separately affect activation and inactivation
Journal of Biological Chemistry, 2010Co-Authors: Viktor Yarotskyy, Guofeng Gao, Sindura B Ganapathi, Blaise Z Peterson, Keith S ElmslieAbstract:L-type (CaV1.2) calcium channel antagonists play an important role in the treatment of cardiovascular disease. (R)-Roscovitine, a trisubstituted purine, has been shown to inhibit L-currents by slowing activation and enhancing inactivation. This study utilized molecular and pharmacological approaches to determine whether these effects result from (R)-Roscovitine binding to a single site. Using the S enantiomer, we find that (S)-Roscovitine enhances inactivation without affecting activation, which suggests multiple sites. This was further supported in studies using chimeric channels comprised of N- and L-channel domains. Those chimeras containing L-channel domains I and IV showed (R)-Roscovitine-induced slowed activation like that of wild type L-channels, whereas chimeric channels containing L-channel domain I responded to (R)-Roscovitine with enhanced inactivation. We conclude that (R)-Roscovitine binds to distinct sites on L-type channels to slow activation and enhance inactivation. These sites appear to be unique from other calcium channel antagonist sites that reside within domains III and IV and are thus novel sites that could be exploited for future drug development. Trisubstituted purines could become a new class of drugs for the treatment of diseases related to hyperfunction of L-type channels, such as Torsades de Pointes.
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Roscovitine a cyclin dependent kinase inhibitor affects several gating mechanisms to inhibit cardiac l type ca v 1 2 calcium channels
British Journal of Pharmacology, 2007Co-Authors: Viktor Yarotskyy, Keith S ElmslieAbstract:Background and purpose: L-type calcium channels (Ca(V)1.2) play an important role in cardiac contraction. Roscovitine, a cyclin-dependent kinase inhibitor and promising anticancer drug, has been shown to affect Ca(V)1.2 by inhibiting current amplitude and slowing activation. This research investigates the mechanism by which Roscovitine inhibits Ca(V)1.2 channels. Experimental approach: Ca(V)1.2 channels were transfected into HEK 293 cells, using the calcium phosphate precipitation method, and currents were measured using the whole-cell patch clamp technique. Key results: Roscovitine slows activation at all voltages, which precludes one previously proposed mechanism. In addition, Roscovitine enhances voltage-dependent, but not calcium-dependent inactivation. This enhancement resulted from both an acceleration of inactivation and a slowing of the recovery from inactivation. Internally applied Roscovitine failed to affect Ca(V)1.2 currents, which supports a kinase-independent mechanism and extracellular binding site. Unlike the dihydropyridines, closed state inactivation was not affected by Roscovitine. Inactivation was enhanced in a dose-dependent manner with an IC50=29.5±12 μM, which is close to that for slow activation and inhibition. Conclusions and implications: We conclude that Roscovitine binds to an extracellular site on Ca(V)1.2 channels to inhibit current by both slowing activation and enhancing inactivation. Purine-based drugs could become a new option for treatment of diseases that benefit from L-channel inhibition such as cardiac arrhythmias and hypertension. British Journal of Pharmacology (2007) 152, 386–395; doi:10.1038/sj.bjp.0707414; published online 13 August 2007
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Roscovitine differentially affects cav2 and kv channels by binding to the open state
Neuropharmacology, 2007Co-Authors: Zafir Buraei, Keith S Elmslie, Geoffrey G SchofieldAbstract:Abstract Roscovitine potently inhibits cyclin-dependent kinases (CDK) and can independently slow the closing of neuronal (CaV2.2) calcium channels. We were interested if this drug could affect other ion channels similarly. Using whole cell recordings, we found that Roscovitine specifically slows deactivation of all CaV2 channels (N, P/Q and R) by binding to the open state. This effect had a rapid onset and EC50 = 54, 120 and 54 μM for N-, P/Q-, and R-type channels, respectively. Deactivation of other channel types was not slowed, including L-type calcium channels (CaV1.2, CaV1.3), potassium channels (native, Kv4.2, Kv2.1 and Kv1.3), and native sodium channels. However, most of the channels tested were inhibited by Roscovitine. The inhibition was characterized by slow development and a lower affinity (EC50 = 100–300 μM). Surprisingly, potassium channels were rapidly inhibited with an EC50 = 23 μM, which is similar to the EC50 for Roscovitine block of cell division [Meijer, L., Borgne, A., Mulner, O., Chong, J., Blow, J., Inagaki, N., Inagaki, M., Delcros, J., Moulinoux, J., 1997. Biochemical and cellular effects of Roscovitine, a potent and selective inhibitor of the cyclin-dependent kinases cdc2, cdk2 and cdk5. Eur. J. Biochem. 243, 527–536]. Potassium current inhibition seemed to result from open channel block. The high potency of these two rapid onset effects makes them complicating factors for ongoing clinical trials and research using Roscovitine. Thus, the physiology and pharmacology of slow CaV2 deactivation and potassium channel block must be explored.
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slowed n type calcium channel cav2 2 deactivation by the cyclin dependent kinase inhibitor Roscovitine
Biophysical Journal, 2005Co-Authors: Zafir Buraei, Mircea Anghelescu, Keith S ElmslieAbstract:The lack of a calcium channel agonist (e.g., BayK8644) for CaV2 channels has impeded their investigation. Roscovitine, a potent inhibitor of cyclin-dependent kinases 1, 2, and 5, has recently been reported to slow the deactivation of P/Q-type calcium channels (CaV2.1). We show that Roscovitine also slows deactivation (EC50 ∼53 μM) of N-type calcium channels (CaV2.2) and investigate gating alterations induced by Roscovitine. The onset of slowed deactivation was rapid (∼2 s), which contrasts with a slower effect of Roscovitine to inhibit N-current (EC50 ∼300 μM). Slow deactivation was specific to Roscovitine, since it could not be induced by a closely related cyclin-dependent kinase inhibitor, olomoucine (300 μM). Intracellularly applied Roscovitine failed to slow deactivation, which implies an extracellular binding site. The Roscovitine-induced slow deactivation was accompanied by a slight left shift in the activation-voltage relationship, slower activation at negative potentials, and increased inactivation. Additional data showed that Roscovitine preferentially binds to the open channel to slow deactivation. A model where Roscovitine reduced a backward rate constant between two open states was able to reproduce the effect of Roscovitine on both activation and deactivation.
Nassima Oumata - One of the best experts on this subject based on the ideXlab platform.
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structural analogues of Roscovitine rescue the intracellular traffic and the function of er retained abcb4 variants in cell models
Scientific Reports, 2019Co-Authors: Virginie Vauthier, Nassima Oumata, Jeanlouis Delaunay, Alix Bruneau, Annemarie Durandschneider, Tounsia Aitslimane, C Housset, Amel Ben Saad, Jonathan Elie, Laurent MeijerAbstract:Adenosine triphosphate binding cassette transporter, subfamily B member 4 (ABCB4) is the transporter of phosphatidylcholine at the canalicular membrane of hepatocytes. ABCB4 deficiency, due to genetic variations, is responsible for progressive familial intrahepatic cholestasis type 3 (PFIC3) and other rare biliary diseases. Roscovitine is a molecule in clinical trial that was shown to correct the F508del variant of cystic fibrosis transmembrane conductance regulator (CFTR), another ABC transporter. In the present study, we hypothesized that Roscovitine could act as a corrector of ABCB4 traffic-defective variants. Using HEK and HepG2 cells, we showed that Roscovitine corrected the traffic and localisation at the plasma membrane of ABCB4-I541F, a prototypical intracellularly retained variant. However, Roscovitine caused cytotoxicity, which urged us to synthesize non-toxic structural analogues. Roscovitine analogues were able to correct the intracellular traffic of ABCB4-I541F in HepG2 cells. Importantly, the phospholipid secretion activity of this variant was substantially rescued by three analogues (MRT2-235, MRT2-237 and MRT2-243) in HEK cells. We showed that these analogues also triggered the rescue of intracellular traffic and function of two other intracellularly retained ABCB4 variants, i.e. I490T and L556R. Our results indicate that structural analogues of Roscovitine can rescue genetic variations altering the intracellular traffic of ABCB4 and should be considered as therapeutic means for severe biliary diseases caused by this class of variations.
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modulating innate and adaptive immunity by r Roscovitine potential therapeutic opportunity in cystic fibrosis
Journal of Innate Immunity, 2016Co-Authors: Laurent Meijer, Deborah J. Nelson, Vladimir Riazanski, Nadège Loaëc, Nassima Oumata, Hervé Galons, Aida G Gabdoulkhakova, Genevieve Heryarnaud, Rozenn Le Berre, Emmanuel NowakAbstract:(R)-Roscovitine, a pharmacological inhibitor of kinases, is currently in phase II clinical trial as a drug candidate for the treatment of cancers, Cushing's disease and rheumatoid arthritis. We here review the data that support the investigation of (R)-Roscovitine as a potential therapeutic agent for the treatment of cystic fibrosis (CF). (R)-Roscovitine displays four independent properties that may favorably combine against CF: (1) it partially protects F508del-CFTR from proteolytic degradation and favors its trafficking to the plasma membrane; (2) by increasing membrane targeting of the TRPC6 ion channel, it rescues acidification in phagolysosomes of CF alveolar macrophages (which show abnormally high pH) and consequently restores their bactericidal activity; (3) its effects on neutrophils (induction of apoptosis), eosinophils (inhibition of degranulation/induction of apoptosis) and lymphocytes (modification of the Th17/Treg balance in favor of the differentiation of anti-inflammatory lymphocytes and reduced production of various interleukins, notably IL-17A) contribute to the resolution of inflammation and restoration of innate immunity, and (4) Roscovitine displays analgesic properties in animal pain models. The fact that (R)-Roscovitine has undergone extensive preclinical safety/pharmacology studies, and phase I and II clinical trials in cancer patients, encourages its repurposing as a CF drug candidate.
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134 Rationale for evaluating (R)-Roscovitine (Seliciclib) in patients with cystic fibrosis
Journal of Cystic Fibrosis, 2015Co-Authors: Laurent Meijer, Deborah J. Nelson, Vladimir Riazanski, A.g. Gabdulkhakova, G. Héry-arnaud, R. Le Berre, Nadège Loaëc, Nassima Oumata, Hervé Galons, Emmanuel NowakAbstract:Objectives (R)-Roscovitine, an inhibitor of cyclin-dependent kinases, is currently under clinical evaluation as a drug candidate against various cancers, Cushing disease and rheumatoid arthritis. Roscovitine has diverse biological properties that could be potentially beneficial in the treatment of CF. Results 1Roscovitine acts as a proteostasis regulator that corrects the trafficking of ΔF508-CFTR. 2Roscovitine improves the bactericidal properties of macrophages from CF patients, by affecting the TRPC6 calcium channel (independently of the CFTR mutation) and by lowering the intraphagolysosomal pH that is abnormally elevated in CF macrophages. 3Its main metabolite also shows a ΔF508-CFTR ‘corrector' effect and biological activity on macrophages, despite lack of kinase inhibitory effects. 4Roscovitine has an anti-inflammatory effect likely originating from its ability to promote neutrophil apoptosis. 5Roscovitine reduces eosinophil degranulation and promotes apoptosis. 6Roscovitine suppresses CD4+ T helper cells differentiation into Th17 (pro-inflammatory lymphocytes) and promotes their differentiation into Tregs (anti-inflammatory lymphocytes). 7Roscovitine is an orally available drug which has undergone preclinical pharmacological and toxicological studies, extensive phase I and II clinical trials, in particular against lung cancer. Conclusion Altogether these data suggest that repurposing Roscovitine for CF is a therapeutically and economically valid proposal. We will present the first clinical protocol designed to validate safety and potential beneficial effects of Roscovitine in CF patients with chronic lung Pseudomonas aeruginosa infection.
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Roscovitine is a proteostasis regulator that corrects the trafficking defect of f508del cftr by a cdk independent mechanism
British Journal of Pharmacology, 2014Co-Authors: Caroline Norez, Nassima Oumata, Hervé Galons, Clarisse Vandebrouck, J Bertrand, Sabrina Noel, E Durieu, Fabrice Antigny, Aurelien Chatelier, Patrick BoisAbstract:Background and Purpose The most common mutation in cystic fibrosis (CF), F508del, causes defects in trafficking, channel gating and endocytosis of the CF transmembrane conductance regulator (CFTR) protein. Because CF is an orphan disease, therapeutic strategies aimed at improving mutant CFTR functions are needed to target the root cause of CF. Experimental Approach Human CF airway epithelial cells were treated with Roscovitine 100 μM for 2 h before CFTR maturation, expression and activity were examined. The mechanism of action of Roscovitine was explored by recording the effect of depleting endoplasmic reticulum (ER) Ca2+ on the F508del-CFTR/calnexin interaction and by measuring proteasome activity. Key Results Of the cyclin-dependent kinase (CDK) inhibitors investigated, Roscovitine was found to restore the cell surface expression and defective channel function of F508del-CFTR in human CF airway epithelial cells. Neither olomoucine nor (S)-CR8, two very efficient CDK inhibitors, corrected F508del-CFTR trafficking demonstrating that the correcting effect of Roscovitine was independent of CDK inhibition. Competition studies with inhibitors of the ER quality control (ERQC) indicated that Roscovitine acts on the calnexin pathway and on the degradation machinery. Roscovitine was shown (i) to partially inhibit the interaction between F508del-CFTR and calnexin by depleting ER Ca2+ and (ii) to directly inhibit the proteasome activity in a Ca2+-independent manner. Conclusions and Implications Roscovitine is able to correct the defective function of F508del-CFTR by preventing the ability of the ERQC to interact with and degrade F508del-CFTR via two synergistic but CDK-independent mechanisms. Roscovitine has potential as a pharmacological therapy for CF.
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cdk inhibitors r Roscovitine and s cr8 effectively block renal and hepatic cystogenesis in an orthologous model of adpkd
Cell Cycle, 2012Co-Authors: Nikolay O Bukanov, Laurent Meijer, Nassima Oumata, Hervé Galons, Sarah Moreno, Thomas A Natoli, Kelly A Rogers, Laurie A Smith, Steven R Ledbetter, Oxana IbraghimovbeskrovnayaAbstract:Autosomal dominant polycystic kidney disease (ADPKD) and other forms of PKD are associated with dysregulated cell cycle and proliferation. Although no effective therapy for the treatment of PKD is currently available, possible mechanism-based approaches are beginning to emerge. A therapeutic intervention targeting aberrant cilia-cell cycle connection using CDK-inhibitor R-Roscovitine showed effective arrest of PKD in jck and cpk models that are not orthologous to human ADPKD. To evaluate whether CDK inhibition approach will translate into efficacy in an orthologous model of ADPKD, we tested R-Roscovitine and its derivative S-CR8 in a model with a conditionally inactivated Pkd1 gene (Pkd1 cKO). Similar to ADPKD, Pkd1 cKO mice developed renal and hepatic cysts. Treatment of Pkd1 cKO mice with R-Roscovitine and its more potent and selective analog S-CR8 significantly reduced renal and hepatic cystogenesis and attenuated kidney function decline. Mechanism of action studies demonstrated effective blockade of cell cycle and proliferation and reduction of apoptosis. Together, these data validate CDK inhibition as a novel and effective approach for the treatment of ADPKD.
K Bettayeb - One of the best experts on this subject based on the ideXlab platform.
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CDK Inhibitors Roscovitine and CR8 Trigger Mcl-1 Down-Regulation and Apoptotic Cell Death in Neuroblastoma Cells
Genes & Cancer, 2010Co-Authors: K Bettayeb, Nadège Loaëc, Alison J Hole, Sonja Baumli, Jane A Endicott, Dianne Baunbæk, Claire Delehouzé, Sétha Douc-rasy, Jean Bénard, Nassima OumataAbstract:Neuroblastoma (NB), the most frequent extracranial solid tumor of children accounting for nearly 15% of all childhood cancer mortality, displays overexpression of antiapoptotic Bcl-2 and Mcl-1 in aggressive forms of the disease. The clinical phase 2 drug Roscovitine (CYC202, seliciclib), a relatively selective inhibitor of cyclin-dependent kinases (CDKs), and CR8, a recently developed and more potent analog, induce concentration-dependent apoptotic cell death of NB cells (average IC 50 values: 24.2 µM and 0.4 µM for Roscovitine and CR8, respectively). Both Roscovitine and CR8 trigger rapid down- regulation of the short-lived survival factor Mcl-1 in the 9 investigated human NB cell lines. This effect was further analyzed in the human SH-SY5Y NB cell line. Down-regulation of Mcl-1 appears to depend on inhibition of CDKs rather than on interaction of Roscovitine and CR8 with their secondary targets. CR8 is an adenosine triphosphate-competitive inhibitor of CDK9, and the structure of a CDK9/cyclin T/CR8 complex is described. Mcl-1 down- regulation occurs both at the mRNA and protein levels. This effect can be accounted for by a reduction in Mcl-1 protein synthesis, under stable Mcl-1 degradation conditions. Mcl-1 down-regulation is accompanied by a transient increase in free Noxa, a proapoptotic factor. Mcl-1 down-regulation occurs independently of the presence or up-regulation of p53 and of the MYCN status. Taken together, these results suggest that the clinical drug Roscovitine and its novel analog CR8 induce apoptotic tumor cell death by down-regulating Mcl-1, a key survival factor expressed in all NB cell lines. CDK inhibition may thus constitute a new approach to treat refractory high-risk NB.
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Pyrazolo[1,5-a]-1,3,5-triazine as a purine bioisostere: access to potent cyclin-dependent kinase inhibitor (R)-Roscovitine analogue.
Journal of Medicinal Chemistry, 2009Co-Authors: Florence Popowycz, Yoan Ferandin, K Bettayeb, Guy Fournet, Oscar M Tirado, Vicente Notario, Cédric Schneider, Cyrile Lamigeon, Silvia Mateo-lozano, Pierre ColasAbstract:Pharmacological inhibitors of cyclin-dependent kinases (CDKs) have a wide therapeutic potential. Among the CDK inhibitors currently under clinical trials, the 2,6,9-trisubstituted purine (R)-Roscovitine displays rather high selectivity, low toxicity, and promising antitumor activity. In an effort to improve this structure, we synthesized several bioisosteres of Roscovitine. Surprisingly, one of them, pyrazolo[1,5-a]-1,3,5-triazine 7a (N-&-N1, GP0210), displayed significantly higher potency, compared to (R)-Roscovitine and imidazo[2,1-f]-1,2,4-triazine 13 (N-&-N2, GP0212), at inhibiting various CDKs and at inducing cell death in a wide variety of human tumor cell lines. This approach may thus provide second generation analogues with enhanced biomedical potential.
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CR8, a potent and selective, Roscovitine-derived inhibitor of cyclin-dependent kinases
Oncogene, 2008Co-Authors: K Bettayeb, Nassima Oumata, Hervé Galons, Yoan Ferandin, A Echalier, J A Endicott, L MeijerAbstract:Among the ten pharmacological inhibitors of cyclin-dependent kinases (CDKs) currently in clinical trials, the purine Roscovitine (CYC202, Seliciclib) is undergoing phase 2 trials against non-small-cell lung and nasopharyngeal cancers. An extensive medicinal chemistry study, designed to generate more potent analogues of Roscovitine, led to the identification of an optimal substitution at the N6 position (compound CR8). An extensive selectivity study (108 kinases) highlights the exquisite selectivity of CR8 for CDK1/2/3/5/7/9. CR8 was 2- to 4-fold more potent than (R)-Roscovitine at inhibiting these kinases. Cocrystal structures of (R)-CR8 and (R)-Roscovitine with pCDK2/cyclin A showed that both inhibitors adopt essentially identical positions. The cellular effects of CR8 and (R)-Roscovitine were investigated in human neuroblastoma SH-SY5Y cells. CR8 inhibited the phosphorylation of CDK1 and 9 substrates, with a 25–50 times higher potency compared to (R)-Roscovitine. CR8 was consistently more potent than (R)-Roscovitine at inducing apoptotic cell death parameters: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium reduction (40-fold), lactate dehydrogenase release (35-fold), caspases activation (68-fold) and poly-(ADP-ribose)polymerase cleavage (50-fold). This improved cell death-inducing activity of CR8 over (R)-Roscovitine was observed in 25 different cell lines. Altogether these results show that second-generation analogues of (R)-Roscovitine can be designed with improved antitumor potential.
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n n a new class of cell death inducing kinase inhibitors derived from the purine Roscovitine
Molecular Cancer Therapeutics, 2008Co-Authors: K Bettayeb, Yoan Ferandin, A Echalier, Moustapha Hassan, Jane A Endicott, Hatem Sallam, Florence Popowycz, Guy Fournet, Philippe Bernard, Benoit JosephAbstract:Cyclin-dependent kinases (CDKs) and their regulators show frequent abnormalities in tumors. Ten low molecular weight pharmacologic inhibitors of CDKs are currently in clinical trials against various cancers, including the 2,6,9-trisubstituted purine (R)-Roscovitine (CYC202/Seliciclib). We here report the characterization of N-&-N1, a bioisoster of Roscovitine displaying improved antitumoral properties. N-&-N1 shows exquisite selectivity for CDKs, with 2- to 3-fold enhanced potency compared with (R)-Roscovitine. Inhibition of retinoblastoma protein phosphorylation and RNA polymerase II Ser2 phosphorylation in neuroblastoma SH-SY5Y cells exposed to N-&-N1 indicates that N-&-N1 is able to inhibit CDKs in a cellular context. N-&-N1 also down-regulates the expression of RNA polymerase. Cocrystal structures of N-&-N1 and (R)-Roscovitine in complex with CDK2/cyclin A reveal that both inhibitors adopt similar binding modes. A competitive assay shows that, compared with (R)-Roscovitine, N-&-N1 has reduced affinity for Erk2 and pyridoxal kinase. N-&-N1 triggers cell death in a panel of diverse cell lines. Cell death is accompanied by events characteristic of apoptosis: cytochrome c release, activation of effector caspases, and poly(ADP-ribose) polymerase cleavage. Induction of p53 and p21CIP1 and down-regulation of the Mcl-1 antiapoptotic factor were also observed. Studies in mice show that N-&-N1 has pharmacokinetics properties similar to those of (R)-Roscovitine. Altogether, these results show that analogues of (R)-Roscovitine can be designed with improved antitumor potential.
Hervé Galons - One of the best experts on this subject based on the ideXlab platform.
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modulating innate and adaptive immunity by r Roscovitine potential therapeutic opportunity in cystic fibrosis
Journal of Innate Immunity, 2016Co-Authors: Laurent Meijer, Deborah J. Nelson, Vladimir Riazanski, Nadège Loaëc, Nassima Oumata, Hervé Galons, Aida G Gabdoulkhakova, Genevieve Heryarnaud, Rozenn Le Berre, Emmanuel NowakAbstract:(R)-Roscovitine, a pharmacological inhibitor of kinases, is currently in phase II clinical trial as a drug candidate for the treatment of cancers, Cushing's disease and rheumatoid arthritis. We here review the data that support the investigation of (R)-Roscovitine as a potential therapeutic agent for the treatment of cystic fibrosis (CF). (R)-Roscovitine displays four independent properties that may favorably combine against CF: (1) it partially protects F508del-CFTR from proteolytic degradation and favors its trafficking to the plasma membrane; (2) by increasing membrane targeting of the TRPC6 ion channel, it rescues acidification in phagolysosomes of CF alveolar macrophages (which show abnormally high pH) and consequently restores their bactericidal activity; (3) its effects on neutrophils (induction of apoptosis), eosinophils (inhibition of degranulation/induction of apoptosis) and lymphocytes (modification of the Th17/Treg balance in favor of the differentiation of anti-inflammatory lymphocytes and reduced production of various interleukins, notably IL-17A) contribute to the resolution of inflammation and restoration of innate immunity, and (4) Roscovitine displays analgesic properties in animal pain models. The fact that (R)-Roscovitine has undergone extensive preclinical safety/pharmacology studies, and phase I and II clinical trials in cancer patients, encourages its repurposing as a CF drug candidate.
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134 Rationale for evaluating (R)-Roscovitine (Seliciclib) in patients with cystic fibrosis
Journal of Cystic Fibrosis, 2015Co-Authors: Laurent Meijer, Deborah J. Nelson, Vladimir Riazanski, A.g. Gabdulkhakova, G. Héry-arnaud, R. Le Berre, Nadège Loaëc, Nassima Oumata, Hervé Galons, Emmanuel NowakAbstract:Objectives (R)-Roscovitine, an inhibitor of cyclin-dependent kinases, is currently under clinical evaluation as a drug candidate against various cancers, Cushing disease and rheumatoid arthritis. Roscovitine has diverse biological properties that could be potentially beneficial in the treatment of CF. Results 1Roscovitine acts as a proteostasis regulator that corrects the trafficking of ΔF508-CFTR. 2Roscovitine improves the bactericidal properties of macrophages from CF patients, by affecting the TRPC6 calcium channel (independently of the CFTR mutation) and by lowering the intraphagolysosomal pH that is abnormally elevated in CF macrophages. 3Its main metabolite also shows a ΔF508-CFTR ‘corrector' effect and biological activity on macrophages, despite lack of kinase inhibitory effects. 4Roscovitine has an anti-inflammatory effect likely originating from its ability to promote neutrophil apoptosis. 5Roscovitine reduces eosinophil degranulation and promotes apoptosis. 6Roscovitine suppresses CD4+ T helper cells differentiation into Th17 (pro-inflammatory lymphocytes) and promotes their differentiation into Tregs (anti-inflammatory lymphocytes). 7Roscovitine is an orally available drug which has undergone preclinical pharmacological and toxicological studies, extensive phase I and II clinical trials, in particular against lung cancer. Conclusion Altogether these data suggest that repurposing Roscovitine for CF is a therapeutically and economically valid proposal. We will present the first clinical protocol designed to validate safety and potential beneficial effects of Roscovitine in CF patients with chronic lung Pseudomonas aeruginosa infection.
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Roscovitine is a proteostasis regulator that corrects the trafficking defect of f508del cftr by a cdk independent mechanism
British Journal of Pharmacology, 2014Co-Authors: Caroline Norez, Nassima Oumata, Hervé Galons, Clarisse Vandebrouck, J Bertrand, Sabrina Noel, E Durieu, Fabrice Antigny, Aurelien Chatelier, Patrick BoisAbstract:Background and Purpose The most common mutation in cystic fibrosis (CF), F508del, causes defects in trafficking, channel gating and endocytosis of the CF transmembrane conductance regulator (CFTR) protein. Because CF is an orphan disease, therapeutic strategies aimed at improving mutant CFTR functions are needed to target the root cause of CF. Experimental Approach Human CF airway epithelial cells were treated with Roscovitine 100 μM for 2 h before CFTR maturation, expression and activity were examined. The mechanism of action of Roscovitine was explored by recording the effect of depleting endoplasmic reticulum (ER) Ca2+ on the F508del-CFTR/calnexin interaction and by measuring proteasome activity. Key Results Of the cyclin-dependent kinase (CDK) inhibitors investigated, Roscovitine was found to restore the cell surface expression and defective channel function of F508del-CFTR in human CF airway epithelial cells. Neither olomoucine nor (S)-CR8, two very efficient CDK inhibitors, corrected F508del-CFTR trafficking demonstrating that the correcting effect of Roscovitine was independent of CDK inhibition. Competition studies with inhibitors of the ER quality control (ERQC) indicated that Roscovitine acts on the calnexin pathway and on the degradation machinery. Roscovitine was shown (i) to partially inhibit the interaction between F508del-CFTR and calnexin by depleting ER Ca2+ and (ii) to directly inhibit the proteasome activity in a Ca2+-independent manner. Conclusions and Implications Roscovitine is able to correct the defective function of F508del-CFTR by preventing the ability of the ERQC to interact with and degrade F508del-CFTR via two synergistic but CDK-independent mechanisms. Roscovitine has potential as a pharmacological therapy for CF.
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cdk inhibitors r Roscovitine and s cr8 effectively block renal and hepatic cystogenesis in an orthologous model of adpkd
Cell Cycle, 2012Co-Authors: Nikolay O Bukanov, Laurent Meijer, Nassima Oumata, Hervé Galons, Sarah Moreno, Thomas A Natoli, Kelly A Rogers, Laurie A Smith, Steven R Ledbetter, Oxana IbraghimovbeskrovnayaAbstract:Autosomal dominant polycystic kidney disease (ADPKD) and other forms of PKD are associated with dysregulated cell cycle and proliferation. Although no effective therapy for the treatment of PKD is currently available, possible mechanism-based approaches are beginning to emerge. A therapeutic intervention targeting aberrant cilia-cell cycle connection using CDK-inhibitor R-Roscovitine showed effective arrest of PKD in jck and cpk models that are not orthologous to human ADPKD. To evaluate whether CDK inhibition approach will translate into efficacy in an orthologous model of ADPKD, we tested R-Roscovitine and its derivative S-CR8 in a model with a conditionally inactivated Pkd1 gene (Pkd1 cKO). Similar to ADPKD, Pkd1 cKO mice developed renal and hepatic cysts. Treatment of Pkd1 cKO mice with R-Roscovitine and its more potent and selective analog S-CR8 significantly reduced renal and hepatic cystogenesis and attenuated kidney function decline. Mechanism of action studies demonstrated effective blockade of cell cycle and proliferation and reduction of apoptosis. Together, these data validate CDK inhibition as a novel and effective approach for the treatment of ADPKD.
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CR8, a potent and selective, Roscovitine-derived inhibitor of cyclin-dependent kinases
Oncogene, 2008Co-Authors: K Bettayeb, Nassima Oumata, Hervé Galons, Yoan Ferandin, A Echalier, J A Endicott, L MeijerAbstract:Among the ten pharmacological inhibitors of cyclin-dependent kinases (CDKs) currently in clinical trials, the purine Roscovitine (CYC202, Seliciclib) is undergoing phase 2 trials against non-small-cell lung and nasopharyngeal cancers. An extensive medicinal chemistry study, designed to generate more potent analogues of Roscovitine, led to the identification of an optimal substitution at the N6 position (compound CR8). An extensive selectivity study (108 kinases) highlights the exquisite selectivity of CR8 for CDK1/2/3/5/7/9. CR8 was 2- to 4-fold more potent than (R)-Roscovitine at inhibiting these kinases. Cocrystal structures of (R)-CR8 and (R)-Roscovitine with pCDK2/cyclin A showed that both inhibitors adopt essentially identical positions. The cellular effects of CR8 and (R)-Roscovitine were investigated in human neuroblastoma SH-SY5Y cells. CR8 inhibited the phosphorylation of CDK1 and 9 substrates, with a 25–50 times higher potency compared to (R)-Roscovitine. CR8 was consistently more potent than (R)-Roscovitine at inducing apoptotic cell death parameters: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium reduction (40-fold), lactate dehydrogenase release (35-fold), caspases activation (68-fold) and poly-(ADP-ribose)polymerase cleavage (50-fold). This improved cell death-inducing activity of CR8 over (R)-Roscovitine was observed in 25 different cell lines. Altogether these results show that second-generation analogues of (R)-Roscovitine can be designed with improved antitumor potential.
