The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Juan Carlos Lacal - One of the best experts on this subject based on the ideXlab platform.
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Choline Kinase an unexpected journey for a precision medicine strategy in human diseases
Pharmaceutics, 2021Co-Authors: Juan Carlos Lacal, Tahl Zimmerman, Joaquin M CamposAbstract:Choline Kinase (ChoK) is a cytosolic enzyme that catalyzes the phosphorylation of Choline to form phosphorylCholine (PCho) in the presence of ATP and magnesium. ChoK is required for the synthesis of key membrane phospholipids and is involved in malignant transformation in a large variety of human tumours. Active compounds against ChoK have been identified and proposed as antitumor agents. The ChoK inhibitory and antiproliferative activities of symmetrical bispyridinium and bisquinolinium compounds have been defined using quantitative structure–activity relationships (QSARs) and structural parameters. The design strategy followed in the development of the most active molecules is presented. The selective anticancer activity of these structures is also described. One promising anticancer compound has even entered clinical trials. Recently, ChoKα inhibitors have also been proposed as a novel therapeutic approach against parasites, rheumatoid arthritis, inflammatory processes, and pathogenic bacteria. The evidence for ChoKα as a novel drug target for approaches in precision medicine is discussed.
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Choline Kinase emerges as a promising drug target in gram positive bacteria
Frontiers in Microbiology, 2019Co-Authors: Tahl Zimmerman, Juan Carlos Lacal, Salam A IbrahimAbstract:Both nosocomial pathogens, such as Streptococcus pneumoniae and Haemophilus influenzae and food-borne pathogens, such as Bacillus cereus and Clostridium perfringens are known to be detrimental to human and animal health. The effectiveness of currently used treatments for these pathogens becomes limited as resistant strains emerge. Therefore, new methods for eliminating bacterial pathogens must be developed continuously. This includes establishing novel targets to which drug discovery efforts could be focused. A promising method for discovering new drug targets in prokaryotes is to take advantage of the information available regarding the enzymatic pathways that have been established as drug targets in eukaryotic systems and explore the analogous pathways found in bacterial systems. This is an efficient strategy because the same inhibitors developed at considerable expense to block these pathways in eukaryotic systems could also be employed in prokaryotes. Drugs that are used to prevent diseases involving eukaryotic cells could be repurposed as antibiotics and antimicrobials for the control of bacteria pathogens. This strategy could be pursued whenever the primary and tertiary structures of a target are are conserved between eukaryotic and prokaryotes. A possible novel target fitting these parameters is Choline Kinase (ChoK), whose active site sequences are conserved (Figure 1) and whose tertiary structure (Figure 2) is maintained. Here, we describe why ChoK is a putative drug target by describing its role in the growth and pathogenesis of Gram-positive bacteria S. pneumoniae and the Gram-negative bacteria H. influenzae. Using S. pneumoniae as a model, we also present promising preliminary information that repurposing of drugs known to inhibit the human isoform of ChoK (hChoK), is a promising strategy for blocking the growth of S. pneumoniae cells and inhibiting the activity of the S. pneumoniae isoform of ChoK (sChok), with downstream physiological effects on the cell wall.
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antiplasmodial activity and mechanism of action of rsm 932a a promising synergistic inhibitor of plasmodium falciparum Choline Kinase
Antimicrobial Agents and Chemotherapy, 2013Co-Authors: Tahl Zimmerman, Teresa Gomez Del Pulgar, Carlos Moneriz, Amalia Diez, Jose M Bautista, Arancha Cebrian, Juan Carlos LacalAbstract:We have investigated the mechanism of action of inhibition of the Choline Kinase of P. falciparum (p.f.-ChoK) by two inhibitors of the human ChoKα, MN58b and RSM-932A, which have previously been shown to be potent antitumoral agents. The efficacy of these inhibitors against p.f.-ChoK is investigated using enzymatic and in vitro assays. While MN58b may enter the Choline/phosphoCholine binding site, RSM-932A appears to have an altogether novel mechanism of inhibition and is synergistic with respect to both Choline and ATP. A model of inhibition for RSM-932A in which this inhibitor traps p.f.-ChoK in a phosphorylated intermediate state blocking phosphate transfer to Choline is presented. Importantly, MN58b and RSM-932A have in vitro inhibitory activity in the low nanomolar range and are equally effective against chloroquine-sensitive and chloroquine-resistant strains. RSM-932A and MN58b significantly reduced parasitemia and induced the accumulation of trophozoites and schizonts, blocking intraerythrocytic development and interfering with parasite egress or invasion, suggesting a delay of the parasite maturation stage. The present data provide two new potent structures for the development of antimalarial compounds and validate p.f.-ChoK as an accessible drug target against the parasite.
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Differential activation of Choline Kinase α1 and β1 isoforms by Ras and Rho GTPases.
2013Co-Authors: David Gallego-ortega, Ana Ramirez De Molina, Maria Angeles Ramos, Fatima Valdes-mora, Maria Gonzalez Barderas, Jacinto Sarmentero-estrada, Juan Carlos LacalAbstract:Choline Kinase isoforms were expressed alone or in combination with the indicated Ras and Rho GTPases and the in vitro ChoK activity determined. A) Analysis of ectopic expression by Western Blot in HEK293T transfected cell extracts of ChoKα1 (52 KDa), ChoKβ1(45 KDa), RhoA-QL(22 KDa), Cdc42-QL(25 KDa) and H-rasV12 (23 KDa). Empty vectors were used as controls for the endogenous levels, and GAPDH as loading control. B) and C)In vitro Choline Kinase activity of ChoKα1 or ChoKβ1 in the presence of enhanced expression of constitutive active forms of RhoA, Cdc42 or H-Ras. D) and E)In vitro ethanolamine Kinase activity of ChoKα or ChoKβ in the presence of each indicated constitutive active form of GTPase. The results are represented as fold induction of conversion to the corresponding phosphorylated metabolite determined as total cpm/µg of whole cellular extract, and normalized to the empty vector transfected cells as control. Data shown represent the mean values±SEM of 3 independent experiments, each one performed with duplicate samples. Statistical significance (p≤0.05) is marked by an asterisk comparing to the activity achieved when ChoKα1 or ChoKβ1, where appropriate, are transfected alone.
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Choline Kinase alpha depletion selectively kills tumoral cells
Current Cancer Drug Targets, 2008Co-Authors: Monica Banezcoronel, Ana Ramirez De Molina, Jacinto Sarmentero, Agustin Rodriguezgonzalez, Ma Angeles Ramos, Miguel Angel Garciacabezas, Lourdes Garciaoroz, Juan Carlos LacalAbstract:Choline Kinase (ChoK) comprises a family of cytosolic enzymes involved in the synthesis of phosphatidylCholine (PC), the most abundant phospholipid in eukaryotic cell membranes. One of the ChoK isoforms, Choline Kinase α (ChoKα), is found over expressed in human tumours. Chemical inhibitors able to interfere with ChoK activity have proven to be effective antitumoral drugs in vitro and in vivo. To validate the use of selective ChoKα inhibitors in cancer therapy, we have developed a genetic strategy to interfere specifically with ChoKα activity based on the generation of a shRNA against the alpha isoform of ChoK. Here we demonstrate that specific inhibition of ChoKα by shRNA has antitumor activity. The specific depletion of ChoKα induces apoptosis in several tumor-derived cell lines from breast, bladder, lung and cervix carcinoma tumors, while the viability of normal primary cells is not affected. Furthermore, this selective antiproliferative effect is achieved both under in vitro and in vivo conditions, as demonstrated by an inducible ChoKα suppression system in human tumour xenografts. These results demonstrate that ChoKα inhibition is a useful antitumoral strategy per se, and provides definitive and non-ambiguous evidence that ChoKα can be used as an efficient and selective drug target for cancer therapy.
Arnon Lavie - One of the best experts on this subject based on the ideXlab platform.
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molecular basis for the interaction between human Choline Kinase alpha and the sh3 domain of the c src tyrosine Kinase
Scientific Reports, 2019Co-Authors: Stefanie L Kall, Kindra Whitlatch, Thomas E Smithgall, Arnon LavieAbstract:Choline Kinase alpha is a 457-residue protein that catalyzes the reaction between ATP and Choline to yield ADP and phosphoCholine. This metabolic action has been well studied because of Choline Kinase’s link to cancer malignancy and poor patient prognosis. As the myriad of x-ray crystal structures available for this enzyme show, chemotherapeutic drug design has centered on stopping the catalytic activity of Choline Kinase and reducing the downstream metabolites it produces. Furthermore, these crystal structures only reveal the catalytic domain of the protein, residues 80–457. However, recent studies provide evidence for a non-catalytic protein-binding role for Choline Kinase alpha. Here, we show that Choline Kinase alpha interacts with the SH3 domain of c-Src. Co-precipitation assays, surface plasmon resonance, and crystallographic analysis of a 1.5 A structure demonstrate that this interaction is specific and is mediated by the poly-proline region found N-terminal to the catalytic domain of Choline Kinase. Taken together, these data offer strong evidence that Choline Kinase alpha has a heretofore underappreciated role in protein-protein interactions, which offers an exciting new way to approach drug development against this cancer-enhancing protein.
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identification of a unique inhibitor binding site on Choline Kinase α
Biochemistry, 2018Co-Authors: Stefanie L Kall, Edward J Delikatny, Arnon LavieAbstract:Choline Kinase α (ChoKα) is an enzyme that is upregulated in many types of cancer and has been shown to be tumorigenic. As such, it makes a promising target for inhibiting tumor growth. Though there have been several inhibitors synthesized for ChoKα, not all of them demonstrate the same efficacy in vivo, though the reasons behind this difference in potency are not clear. One particular inhibitor, designated TCD-717, has recently completed phase I clinical trials. Cell culture and in vitro studies support the powerful inhibitory effect TCD-717 has on ChoKα, but an examination of the inhibitor’s interaction with the ChoKα enzyme has been missing prior to this work. Here we detail the 2.35 A structure of ChoKα in complex with TCD-717. Examination of this structure in conjunction with kinetic assays reveals that TCD-717 does not bind directly in the Choline pocket as do previously characterized ChoKα inhibitors, but rather in a proximal but novel location near the surface of the enzyme. The unique binding sit...
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identification of a unique inhibitor binding site on Choline Kinase α
Biochemistry, 2018Co-Authors: Stefanie L Kall, Arnon Lavie, Edward J DelikatnyAbstract:Choline Kinase α (ChoKα) is an enzyme that is upregulated in many types of cancer and has been shown to be tumorigenic. As such, it makes a promising target for inhibiting tumor growth. Though there have been several inhibitors synthesized for ChoKα, not all of them demonstrate the same efficacy in vivo, though the reasons behind this difference in potency are not clear. One particular inhibitor, designated TCD-717, has recently completed phase I clinical trials. Cell culture and in vitro studies support the powerful inhibitory effect TCD-717 has on ChoKα, but an examination of the inhibitor’s interaction with the ChoKα enzyme has been missing prior to this work. Here we detail the 2.35 A structure of ChoKα in complex with TCD-717. Examination of this structure in conjunction with kinetic assays reveals that TCD-717 does not bind directly in the Choline pocket as do previously characterized ChoKα inhibitors, but rather in a proximal but novel location near the surface of the enzyme. The unique binding site identified for TCD-717 lends insight for the future design of more potent in vivo inhibitors for ChoKα.
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balance of human Choline Kinase isoforms is critical for cell cycle regulation implications for the development of Choline Kinase targeted cancer therapy
FEBS Journal, 2012Co-Authors: Jens Gruber, Arnon Lavie, Wei Cun See Too, Mun Teng Wong, Theresa Mcsorley, Manfred KonradAbstract:The enzyme Choline Kinase (CK), which catalyzes the phosphorylation of Choline to phosphorylCholine in the presence of ATP, has an essential role in the biosynthesis of phosphatidylCholine, the major constituent of all mammalian cell membranes. CK is encoded by two separate genes expressing the three isoforms CKα1, CKα2 and CKβ that are active as homodimeric or heterodimeric species. Metabolic changes observed in various cancer cell lines and tumors have been associated with differential and marked up-regulation of the CKα genes, and specific inhibition of CKα activity has been proposed as a potential anti-cancer strategy. As a result, less attention has been given to CKβ and its interaction with CKα. With the aim of profiling the intracellular roles of CKα and CKβ, we used RNA interference (RNAi) as a molecular approach to down-regulate the expression of CK in HeLa cells. Individual and simultaneous RNAi-based silencing of the CK α and β isoforms was achieved using different combinations of knockdown strategies. Efficient knockdown was confirmed by immunodetection using our isoform-specific antibodies and by quantitative real-time PCR. Our analyses of the phenotypic consequences of CK depletion showed the expected lethal effect of CKα knockdown. However, CKβ- and CKα + CKβ-silenced cells had no aberrant phenotype. Therefore, our results support the hypothesis that the balance of the α and β isoforms is critical for cancer cell survival. The suppression of the cancer cell killing effect of CKα silencing by simultaneous knockdown of both isoforms implies that a more effective CK-based anti-cancer strategy can be achieved by reducing cross-reactivity with CKβ.
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elucidation of human Choline Kinase crystal structures in complex with the products adp or phosphoCholine
Journal of Molecular Biology, 2006Co-Authors: Enrico Malito, Nikolina Sekulic, Wei Cun See Too, Manfred Konrad, Arnon LavieAbstract:Abstract Choline Kinase, responsible for the phosphorylation of Choline to phosphoCholine as the first step of the CDP-Choline pathway for the biosynthesis of phosphatidylCholine, has been recognized as a new target for anticancer therapy. Crystal structures of human Choline Kinase in its apo, ADP and phosphoCholine-bound complexes, respectively, reveal the molecular details of the substrate binding sites. ATP binds in a cavity where residues from both the N and C-terminal lobes contribute to form a cleft, while the Choline-binding site constitutes a deep hydrophobic groove in the C-terminal domain with a rim composed of negatively charged residues. Upon binding of Choline, the enzyme undergoes conformational changes independently affecting the N-terminal domain and the ATP-binding loop. From this structural analysis and comparison with other Kinases, and from mutagenesis data on the homologous Caenorhabditis elegans Choline Kinase, a model of the ternary ADP·phosphoCholine complex was built that reveals the molecular basis for the phosphoryl transfer activity of this enzyme.
Dennis E Vance - One of the best experts on this subject based on the ideXlab platform.
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Choline Kinase beta is required for normal endochondral bone formation
Biochimica et Biophysica Acta, 2014Co-Authors: Roger B Sher, Gregory A Cox, Zohreh Khavandgar, Martin Hermansson, Michael R Doschak, Monzur Murshed, Frank Beier, Dennis E VanceAbstract:Abstract Background Choline Kinase has three isoforms encoded by the genes Chka and Chkb. Inactivation of Chka in mice results in embryonic lethality, whereas Chkb−/− mice display neonatal forelimb bone deformations. Methods To understand the mechanisms underlying the bone deformations, we compared the biology and biochemistry of bone formation from embryonic to young adult wild-type (WT) and Chkb−/− mice. Results The deformations are specific to the radius and ulna during the late embryonic stage. The radius and ulna of Chkb−/− mice display expanded hypertrophic zones, unorganized proliferative columns in their growth plates, and delayed formation of primary ossification centers. The differentiation of chondrocytes of Chkb−/− mice was impaired, as was chondrocyte proliferation and expression of matrix metalloproteinases 9 and 13. In chondrocytes from Chkb−/− mice, phosphatidylCholine was slightly lower than in WT mice whereas the amount of phosphoCholine was decreased by approximately 75%. In addition, the radius and ulna from Chkb−/− mice contained fewer osteoclasts along the cartilage/bone interface. Conclusions Chkb has a critical role in the normal embryogenic formation of the radius and ulna in mice. General Significance Our data indicate that Choline Kinase beta plays an important role in endochondral bone formation by modulating growth plate physiology.
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Choline Kinase and its functionthis paper is one of a selection of papers published in this special issue entitled second international symposium on recent advances in basic clinical and social medicine and has undergone the journal s usual peer revi
Biochemistry and Cell Biology, 2010Co-Authors: Dennis E VanceAbstract:Choline Kinase (CK) was discovered in 1953. Progress in understanding the function of CK was slow until its purification in 1984. The subsequent cloning and expression of the cDNA led to the description of the gene structures. Two genes encode Choline Kinase, Chka and Chkb, and 3 isoforms of the enzyme have been identified — CKα-1, CKα-2, and CKβ — and the active form of CK is a hetero- or homo-dimer. More recently, gene-disrupted mice have been described. Mice that lack CKα die early in embryogenesis. In contrast, mice that lack CKβ survive to adulthood, but develop hindlimb muscular dystrophy and forelimb bone deformity. It has been shown that this hindlimb muscular dystrophy is due to decreased biosynthesis of phosphatidylCholine and increased catabolism of phosphatidylCholine in the hindlimbs, but not the forelimbs, of mice. CK and its product phosphoCholine have also been implicated in development of numerous cancers. Thus, a possible treatment for some kinds of cancer may involve drug inhibition of ...
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differential expression of Choline Kinase isoforms in skeletal muscle explains the phenotypic variability in the rostrocaudal muscular dystrophy mouse
Biochimica et Biophysica Acta, 2010Co-Authors: Roger B Sher, Gregory A Cox, Dennis E VanceAbstract:Choline Kinase in mammals is encoded by two genes, Chka and Chkb. Disruption of murine Chka leads to embryonic lethality, whereas a spontaneous genomic deletion in murine Chkb results in neonatal forelimb bone deformity and hindlimb muscular dystrophy. Surprisingly, muscular dystrophy isn't significantly developed in the forelimb. We have investigated the mechanism by which a lack of Choline Kinase beta, encoded by Chkb, results in minimal muscular dystrophy in forelimbs. We have found that Choline Kinase beta is the major isoform in hindlimb muscle and contributes more to Choline Kinase activity, while Choline Kinase alpha is predominant in forelimb muscle and contributes more to Choline Kinase activity. Although Choline Kinase activity is decreased in forelimb muscles of Chkb(-/-) mice, the activity of CTP:phosphoCholine cytidylyltransferase is increased, resulting in enhanced phosphatidylCholine biosynthesis. The activity of phosphatidylCholine phospholipase C is up-regulated while the activity of phospholipase A(2) in forelimb muscle is not altered. Regeneration of forelimb muscles of Chkb(-/-) mice is normal when challenged with cardiotoxin. In contrast to hindlimb muscle, mega-mitochondria are not significantly formed in forelimb muscle of Chkb(-/-) mice. We conclude that the relative lack of muscle degeneration in forelimbs of Chkb(-/-) mice is due to abundant Choline Kinase alpha and the stable homeostasis of phosphatidylCholine.
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understanding the muscular dystrophy caused by deletion of Choline Kinase beta in mice
Biochimica et Biophysica Acta, 2009Co-Authors: Roger B Sher, Gregory A Cox, Dennis E VanceAbstract:article i nfo Choline Kinase in mice is encoded by two genes, Chka and Chkb. Disruption of murine Chka leads to embryonic lethality, whereas a spontaneously occurring genomic deletion in murine Chkb results in neonatal bone deformity and hindlimb muscular dystrophy. We have investigated the mechanism by which a lack of Choline Kinase β, encoded by Chkb, causes hindlimb muscular dystrophy. The biosynthesis of phosphatidylCholine (PC) is impaired in the hindlimbs of Chkb �/� mice, with an accumulation of Choline and decreased amount of phosphoCholine. The activity of CTP:phosphoCholine cytidylyltransferase is also decreased in the hindlimb muscle of mutant mice. Concomitantly, the activities of PC phospholipase C and phospholipase A2 are increased. The mitochondria in Chkb �/� mice are abnormally large and exhibit decreased inner membrane potential. Despite the muscular dystrophy in Chkb �/� mice, we observed increased expression of insulin like growth factor 1 and proliferating cell nuclear antigen. However, regeneration of hindlimb muscles of Chkb �/� mice was impaired when challenged with cardiotoxin. Injection of CDP-Choline increased PC content of hindlimb muscle and decreased creatine Kinase activity in plasma of Chkb �/� mice. We conclude that the hindlimb muscular dystrophy in Chkb �/� mice is due to attenuated PC biosynthesis and enhanced catabolism of PC.
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early embryonic lethality caused by disruption of the gene for Choline Kinase α the first enzyme in phosphatidylCholine biosynthesis
Journal of Biological Chemistry, 2008Co-Authors: Chieko Aoyama, Stephen G Young, Dennis E VanceAbstract:Choline Kinase α (CK-α) is one of two mammalian enzymes that catalyze the phosphorylation of Choline to phosphoCholine in the biosynthesis of the major membrane phospholipid, phosphatidylCholine. We created mice lacking CK-α with an embryonic stem cell line containing an insertional mutation in the gene for CK-α (Chka). Embryos homozygous for the mutant Chka allele were recovered at the blastocyst stage, but not at embryonic day 7.5, indicating that CK-α is crucial for the early development of mouse embryos. Heterozygous mutant mice (Chka+/-) appeared entirely normal in their embryonic development and gross anatomy, and they were fertile. Although Choline Kinase activity was decreased by ∼30%, the amount of phosphatidylCholine in cells and the levels of other enzymes involved in phosphatidylCholine biosynthesis were unaffected. PhosphatidylCholine biosynthesis measured by Choline incorporation into hepatocytes was also not compromised in Chka+/- mice. Enhanced levels of Choline and attenuated levels of phosphoCholine were observed in both the livers and testes of Chka+/- mice. Triacylglycerol and cholesterol ester were elevated ∼2-fold in the livers, whereas neutral lipid profiles in plasma were similar in Chka+/- and wild-type (Chka+/+) mice. Thus, Chka is an essential gene for early embryonic development, but adult mice do not require full expression of the gene for normal levels of phosphatidylCholine.
Antonio Espinosa - One of the best experts on this subject based on the ideXlab platform.
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discovery of a new binding site on human Choline Kinase α1 design synthesis crystallographic studies and biological evaluation of asymmetrical bispyridinium derivatives
Journal of Medicinal Chemistry, 2014Co-Authors: Belen Rubioruiz, Antonio Espinosa, Pablo Riosmarco, Carmen Marco, Miguel A Gallo, Ainoa Figuerolaconchas, Javier Ramostorrecillas, Fermin Capitancanadas, Ma Paz Carrasco, Concepcion RuizAbstract:Human Choline Kinase α (CKα) is a validated drug target for the treatment of cancer. In recent years, a large number of CK inhibitors have been synthesized, and one of them is currently being evaluated in Phase I clinical trials as a treatment for solid tumors. Here we have evaluated a new series of asymmetrical biscationic CK inhibitors by means of enzymatic, crystallographic, and antitumor studies. We demonstrate that one of these structures adopts a completely new binding mode not observed before inducing the aperture of an adjacent binding site. This compound shows antiproliferative and apoptotic effects on cancer cells through activation of caspase-3. Therefore, this study not only provides fruitful insights into the design of more efficient compounds that may target different regions in CKα1 but also explains how these compounds induce apoptosis in cancer cells.
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new non symmetrical Choline Kinase inhibitors
Bioorganic & Medicinal Chemistry, 2013Co-Authors: Santiago Schiaffinoortega, Miguel A Gallo, Antonio Espinosa, Luisa Carlota Lopezcara, Pablo Riosmarco, Maria Paz Carrascojimenez, Carmen Marco, Antonio EntrenaAbstract:Identification of novel and selective anticancer agents remains an important and challenging goal in pharmacological research. Choline Kinase (ChoK) is the first enzyme in the CDP-Choline pathway that synthesizes phosphatidylCholine (PC), the major phospholipid in eukaryotic cell membranes. In the present paper, a new family of non-symmetrical monocationic compounds is developed including a 3-aminophenol moiety, bound to 4-(dimethylamino)- or 4-(pyrrolidin-1-yl)pyridinium cationic heads through several linkers. The most promising compounds in these series as ChoK inhibitors are 3f and 4f, while compounds 3c, 3d and 4c are the better antiproliferative agents. The analysis of the biological data observed in the described series of compounds mays represents a platform for the design of more active molecules.
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the mechanism of allosteric coupling in Choline Kinase α1 revealed by the action of a rationally designed inhibitor
Angewandte Chemie, 2013Co-Authors: Maria Sahunroncero, Antonio Espinosa, Antonio Entrena, Ana Conejogarcia, Belen Rubioruiz, Giorgio Saladino, Adrian Velazquezcampoy, Francesco Luigi Gervasio, Ramon HurtadoguerreroAbstract:Applying a CHOK hold: Combined experimental and computational studies of the binding mode of a rationally designed inhibitor of the dimeric Choline Kinase α1 (CHOKα1) explain the molecular mechanism of negative cooperativity (see scheme) and how the monomers are connected. The results give insight into how the symmetry of the dimer can be partially conserved despite a lack of conservation in the static crystal structures.
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design synthesis theoretical calculations and biological evaluation of new non symmetrical Choline Kinase inhibitors
European Journal of Medicinal Chemistry, 2012Co-Authors: Belen Rubioruiz, Miguel A Gallo, Antonio Espinosa, Pablo Riosmarco, Maria Paz Carrascojimenez, Carmen Marco, Ana Conejogarcia, J L Segovia, Antonio EntrenaAbstract:Inhibition of Choline Kinase (ChoK) has been reported as a therapeutical target in the treatment of some kinds of tumor. In this paper, the design and synthesis of new non-symmetrical monocationic ChoK inhibitors is described, bearing a cationic head and an adenine moiety connected by linkers of different lengths. Docking studies indicate that the cationic head of these compounds could be inserted into the Choline binding site of the enzyme, while the adenine moiety could be stabilized into the ATP binding site. Docking studies also support the difference of activity of the synthesized compounds, which depends on both the substituent at position 4 of the cationic head and the linker length, being dimethylamine and 1,4-diphenylbutane respectively, the most appropriate ones. Compounds 14 (IC(50) = 10.70 ± 0.40 μM) and 17 (IC(50) = 6.21 ± 0.97 μM) are the most potent ChoK inhibitors and suitable for further modification with a view to obtain more potent antitumor compounds.
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Symmetrical bis-quinolinium compounds: new human Choline Kinase inhibitors with antiproliferative activity against the HT-29 cell line.
Journal of medicinal chemistry, 2005Co-Authors: Rosario M. Sanchez-martin, Joaquin M Campos, Miguel A Gallo, Ana Conejo-garcía, Olga Cruz-lopez, Mónica Báñez-coronel, Agustín Rodríguez-gonzález, Juan Carlos Lacal, Antonio EspinosaAbstract:Studies have been aimed at the establishment of structure−activity relationships that define Choline Kinase inhibitory and antiproliferative activities of 40 bisquinolinium compounds. These derivatives have electron-releasing groups at position 4 of the quinolinium ring. It is found that the enzymatic inhibition is closely related to the size of the linker, the 3,3‘-biphenyl moiety being the most suitable. On the other hand, the antiproliferative activity against the HT-29 cancer cell line is less influenced by the linker type and by substituent R4. The corresponding QSAR equation was obtained for the whole set of compounds for the antiproliferative activity, the electronic parameter σR of R4, the molar refractivity of R8, and the lipophilic parameters clog P and πlinker. The most potent antiproliferative agent so far described is 40 for which an IC50 = 0.45 μM was predicted by the QSAR equation, while its experimental value is IC50 = 0.20 μM.
Roger B Sher - One of the best experts on this subject based on the ideXlab platform.
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Choline Kinase beta is required for normal endochondral bone formation
Biochimica et Biophysica Acta, 2014Co-Authors: Roger B Sher, Gregory A Cox, Zohreh Khavandgar, Martin Hermansson, Michael R Doschak, Monzur Murshed, Frank Beier, Dennis E VanceAbstract:Abstract Background Choline Kinase has three isoforms encoded by the genes Chka and Chkb. Inactivation of Chka in mice results in embryonic lethality, whereas Chkb−/− mice display neonatal forelimb bone deformations. Methods To understand the mechanisms underlying the bone deformations, we compared the biology and biochemistry of bone formation from embryonic to young adult wild-type (WT) and Chkb−/− mice. Results The deformations are specific to the radius and ulna during the late embryonic stage. The radius and ulna of Chkb−/− mice display expanded hypertrophic zones, unorganized proliferative columns in their growth plates, and delayed formation of primary ossification centers. The differentiation of chondrocytes of Chkb−/− mice was impaired, as was chondrocyte proliferation and expression of matrix metalloproteinases 9 and 13. In chondrocytes from Chkb−/− mice, phosphatidylCholine was slightly lower than in WT mice whereas the amount of phosphoCholine was decreased by approximately 75%. In addition, the radius and ulna from Chkb−/− mice contained fewer osteoclasts along the cartilage/bone interface. Conclusions Chkb has a critical role in the normal embryogenic formation of the radius and ulna in mice. General Significance Our data indicate that Choline Kinase beta plays an important role in endochondral bone formation by modulating growth plate physiology.
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muscle Choline Kinase beta defect causes mitochondrial dysfunction and increased mitophagy
Human Molecular Genetics, 2011Co-Authors: Satomi Mitsuhashi, Roger B Sher, Hideyuki Hatakeyama, Minako Karahashi, Tomoko Koumura, Ikuya Nonaka, Yukiko K Hayashi, Satoru Noguchi, Yasuhito Nakagawa, Giovanni ManfrediAbstract:Choline Kinase is the first step enzyme for phosphatidylCholine (PC) de novo biosynthesis. Loss of Choline Kinase activity in muscle causes rostrocaudal muscular dystrophy (rmd) in mouse and congenital muscular dystrophy in human, characterized by distinct mitochondrial morphological abnormalities. We performed biochemical and pathological analyses on skeletal muscle mitochondria from rmd mice. No mitochondria were found in the center of muscle fibers, while those located at the periphery of the fibers were significantly enlarged. Muscle mitochondria in rmd mice exhibited significantly decreased PC levels, impaired respiratory chain enzyme activities, decreased mitochondrial ATP synthesis, decreased coenzyme Q and increased superoxide production. Electron microscopy showed the selective autophagic elimination of mitochondria in rmd muscle. Molecular markers of mitophagy, including Parkin, PINK1, LC3, polyubiquitin and p62, were localized to mitochondria of rmd muscle. Quantitative analysis shows that the number of mitochondria in muscle fibers and mitochondrial DNA copy number were decreased. We demonstrated that the genetic defect in Choline Kinase in muscle results in mitochondrial dysfunction and subsequent mitochondrial loss through enhanced activation of mitophagy. These findings provide a first evidence for a pathomechanistic link between de novo PC biosynthesis and mitochondrial abnormality.
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differential expression of Choline Kinase isoforms in skeletal muscle explains the phenotypic variability in the rostrocaudal muscular dystrophy mouse
Biochimica et Biophysica Acta, 2010Co-Authors: Roger B Sher, Gregory A Cox, Dennis E VanceAbstract:Choline Kinase in mammals is encoded by two genes, Chka and Chkb. Disruption of murine Chka leads to embryonic lethality, whereas a spontaneous genomic deletion in murine Chkb results in neonatal forelimb bone deformity and hindlimb muscular dystrophy. Surprisingly, muscular dystrophy isn't significantly developed in the forelimb. We have investigated the mechanism by which a lack of Choline Kinase beta, encoded by Chkb, results in minimal muscular dystrophy in forelimbs. We have found that Choline Kinase beta is the major isoform in hindlimb muscle and contributes more to Choline Kinase activity, while Choline Kinase alpha is predominant in forelimb muscle and contributes more to Choline Kinase activity. Although Choline Kinase activity is decreased in forelimb muscles of Chkb(-/-) mice, the activity of CTP:phosphoCholine cytidylyltransferase is increased, resulting in enhanced phosphatidylCholine biosynthesis. The activity of phosphatidylCholine phospholipase C is up-regulated while the activity of phospholipase A(2) in forelimb muscle is not altered. Regeneration of forelimb muscles of Chkb(-/-) mice is normal when challenged with cardiotoxin. In contrast to hindlimb muscle, mega-mitochondria are not significantly formed in forelimb muscle of Chkb(-/-) mice. We conclude that the relative lack of muscle degeneration in forelimbs of Chkb(-/-) mice is due to abundant Choline Kinase alpha and the stable homeostasis of phosphatidylCholine.
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understanding the muscular dystrophy caused by deletion of Choline Kinase beta in mice
Biochimica et Biophysica Acta, 2009Co-Authors: Roger B Sher, Gregory A Cox, Dennis E VanceAbstract:article i nfo Choline Kinase in mice is encoded by two genes, Chka and Chkb. Disruption of murine Chka leads to embryonic lethality, whereas a spontaneously occurring genomic deletion in murine Chkb results in neonatal bone deformity and hindlimb muscular dystrophy. We have investigated the mechanism by which a lack of Choline Kinase β, encoded by Chkb, causes hindlimb muscular dystrophy. The biosynthesis of phosphatidylCholine (PC) is impaired in the hindlimbs of Chkb �/� mice, with an accumulation of Choline and decreased amount of phosphoCholine. The activity of CTP:phosphoCholine cytidylyltransferase is also decreased in the hindlimb muscle of mutant mice. Concomitantly, the activities of PC phospholipase C and phospholipase A2 are increased. The mitochondria in Chkb �/� mice are abnormally large and exhibit decreased inner membrane potential. Despite the muscular dystrophy in Chkb �/� mice, we observed increased expression of insulin like growth factor 1 and proliferating cell nuclear antigen. However, regeneration of hindlimb muscles of Chkb �/� mice was impaired when challenged with cardiotoxin. Injection of CDP-Choline increased PC content of hindlimb muscle and decreased creatine Kinase activity in plasma of Chkb �/� mice. We conclude that the hindlimb muscular dystrophy in Chkb �/� mice is due to attenuated PC biosynthesis and enhanced catabolism of PC.
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a rostrocaudal muscular dystrophy caused by a defect in Choline Kinase beta the first enzyme in phosphatidylCholine biosynthesis
Journal of Biological Chemistry, 2006Co-Authors: Roger B Sher, Chieko Aoyama, Kimberly A Huebsch, Janos Kerner, Yan Yang, Wayne N Frankel, Charles L Hoppel, Philip A Wood, Dennis E VanceAbstract:Muscular dystrophies include a diverse group of genetically heterogeneous disorders that together affect 1 in 2000 births worldwide. The diseases are characterized by progressive muscle weakness and wasting that lead to severe disability and often premature death. Rostrocaudal muscular dystrophy (rmd) is a new recessive mouse mutation that causes a rapidly progressive muscular dystrophy and a neonatal forelimb bone deformity. The rmd mutation is a 1.6-kb intragenic deletion within the Choline Kinase beta (Chkb) gene, resulting in a complete loss of CHKB protein and enzymatic activity. CHKB is one of two mammalian Choline Kinase (CHK) enzymes (α and β) that catalyze the phosphorylation of Choline to phosphoCholine in the biosynthesis of the major membrane phospholipid phosphatidylCholine. While mutant rmd mice show a dramatic decrease of CHK activity in all tissues, the dystrophy is only evident in skeletal muscle tissues in an unusual rostral-to-caudal gradient. Minor membrane disruption similar to dysferlinopathies suggest that membrane fusion defects may underlie this dystrophy, because severe membrane disruptions are not evident as determined by creatine Kinase levels, Evans Blue infiltration, and unaltered levels of proteins in the dystrophin-glycoprotein complex. The rmd mutant mouse offers the first demonstration of a defect in a phospholipid biosynthetic enzyme causing muscular dystrophy, representing a unique model for understanding mechanisms of muscle degeneration.