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Sample records for adhesion kinase inhibitor

  1. The effects of CEP-37440, an inhibitor of focal adhesion kinase, in vitro and in vivo on inflammatory breast cancer cells

    OpenAIRE

    Salem, Israa; Alsalahi, Manal; Chervoneva, Inna; Aburto, Lucy D.; Addya, Sankar; Ott, Gregory R.; Ruggeri, Bruce A.; Cristofanilli, Massimo; Fernandez, Sandra V.

    2016-01-01

    Background Inflammatory breast cancer (IBC) is an aggressive type of advanced breast cancer with a poor prognosis. We recently found that focal adhesion kinase 1 (FAK1) is upregulated and phosphorylated (active) in IBC. In this study, we investigated the effect of CEP-37440, a dual inhibitor of FAK1 and anaplastic lymphoma kinase (ALK), using human IBC cell lines and preclinical models of IBC. Methods Cell proliferation assays were performed in the presence of several concentrations of CEP-37...

  2. Quantitative changes in focal adhesion kinase and its inhibitor, FRNK, drive load-dependent expression of costamere components.

    Science.gov (United States)

    Klossner, Stephan; Li, Ruowei; Ruoss, Severin; Durieux, Anne-Cécile; Flück, Martin

    2013-09-15

    Costameres are mechanosensory sites of focal adhesion in the sarcolemma that reinforce the muscle-fiber composite and provide an anchor for myofibrillogenesis. We hypothesized that elevated content of the integrin-associated regulator of costamere turnover in culture, focal adhesion kinase (FAK), drives changes in costamere component content in antigravity muscle in a load-dependent way in correspondence with altered muscle weight. The content of FAK in soleus muscle being phosphorylated at autoregulatory tyrosine 397 (FAK-pY397) was increased after 20 s of stretch. FAK-pY397 content remained elevated after 24 h of stretch-overload due to upregulated FAK content. Overexpression of FAK in soleus muscle fibers by means of gene electrotransfer increased the β1-integrin (+56%) and meta-vinculin (+88%) content. α7-Integrin (P = 0.46) and γ-vinculin (P = 0.18) content was not altered after FAK overexpression. Co-overexpression of the FAK inhibitor FAK-related nonkinase (FRNK) reduced FAK-pY397 content by 33% and increased the percentage of fast-type fibers that arose in connection with hybrid fibers with gene transfer. Transplantation experiments confirmed the association of FRNK expression with slow-to-fast fiber transformation. Seven days of unloading blunted the elevation of FAK-pY397, β1-integrin, and meta-vinculin content with FAK overexpression, and this was reversed by 1 day of reloading. The results highlight that the expression of components for costameric attachment sites of myofibrils is under load- and fiber type-related control via FAK and its inhibitor FRNK.

  3. Focal Adhesion Kinase Inhibitors in Combination with Erlotinib Demonstrate Enhanced Anti-Tumor Activity in Non-Small Cell Lung Cancer.

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    Grant A Howe

    Full Text Available Blockade of epidermal growth factor receptor (EGFR activity has been a primary therapeutic target for non-small cell lung cancers (NSCLC. As patients with wild-type EGFR have demonstrated only modest benefit from EGFR tyrosine kinase inhibitors (TKIs, there is a need for additional therapeutic approaches in patients with wild-type EGFR. As a key component of downstream integrin signalling and known receptor cross-talk with EGFR, we hypothesized that targeting focal adhesion kinase (FAK activity, which has also been shown to correlate with aggressive stage in NSCLC, would lead to enhanced activity of EGFR TKIs. As such, EGFR TKI-resistant NSCLC cells (A549, H1299, H1975 were treated with the EGFR TKI erlotinib and FAK inhibitors (PF-573,228 or PF-562,271 both as single agents and in combination. We determined cell viability, apoptosis and 3-dimensional growth in vitro and assessed tumor growth in vivo. Treatment of EGFR TKI-resistant NSCLC cells with FAK inhibitor alone effectively inhibited cell viability in all cell lines tested; however, its use in combination with the EGFR TKI erlotinib was more effective at reducing cell viability than either treatment alone when tested in both 2- and 3-dimensional assays in vitro, with enhanced benefit seen in A549 cells. This increased efficacy may be due in part to the observed inhibition of Akt phosphorylation when the drugs were used in combination, where again A549 cells demonstrated the most inhibition following treatment with the drug combination. Combining erlotinib with FAK inhibitor was also potent in vivo as evidenced by reduced tumor growth in the A549 mouse xenograft model. We further ascertained that the enhanced sensitivity was irrespective of the LKB1 mutational status. In summary, we demonstrate the effectiveness of combining erlotinib and FAK inhibitors for use in known EGFR wild-type, EGFR TKI resistant cells, with the potential that a subset of cell types, which includes A549, could be

  4. Kinase Inhibitors from Marine Sponges

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    Ana Zivanovic

    2011-10-01

    Full Text Available Protein kinases play a critical role in cell regulation and their deregulation is a contributing factor in an increasing list of diseases including cancer. Marine sponges have yielded over 70 novel compounds to date that exhibit significant inhibitory activity towards a range of protein kinases. These compounds, which belong to diverse structural classes, are reviewed herein, and ordered based upon the kinase that they inhibit. Relevant synthetic studies on the marine natural product kinase inhibitors have also been included.

  5. Focal Adhesion Kinases in Adhesion Structures and Disease

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    Pierre P. Eleniste

    2012-01-01

    Full Text Available Cell adhesion to the extracellular matrix (ECM is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases.

  6. Focal adhesion kinases in adhesion structures and disease.

    Science.gov (United States)

    Eleniste, Pierre P; Bruzzaniti, Angela

    2012-01-01

    Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases. PMID:22888421

  7. Focal Adhesion Kinases in Adhesion Structures and Disease

    OpenAIRE

    Pierre P. Eleniste; Angela Bruzzaniti

    2012-01-01

    Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organiza...

  8. Renal targeting of kinase inhibitors

    NARCIS (Netherlands)

    Dolman, M. E. M.; Fretz, M. M.; Segers, Gj. W.; Lacombe, M.; Prakash, J.; Storm, G.; Hennink, W. E.; Kok, R. J.

    2008-01-01

    Activation of proximal tubular cells by fibrotic and inflammatory mediators is an important hallmark of chronic kidney disease. We have developed a novel strategy to intervene in renal fibrosis, by means of locally delivered kinase inhibitors. Such compounds will display enhanced activity within tub

  9. Protein kinase C involvement in focal adhesion formation

    DEFF Research Database (Denmark)

    Woods, A; Couchman, J R

    1992-01-01

    Matrix molecules such as fibronectin can promote cell attachment, spreading and focal adhesion formation. Although some interactions of fibronectin with cell surface receptors have now been identified, the consequent activation of intracellular messenger systems by cell/matrix interactions have...... still to be elucidated. We show here that the kinase inhibitors H7 and HA1004 reduce focal adhesion and stress fiber formation in response to fibronectin in a dose-dependent manner, and that activators of protein kinase C can promote their formation under conditions where they do not normally form....... Fibroblasts spread within 1h on substrata composed of fibronectin and formed focal adhesions by 3h, as monitored by interference reflection microscopy (IRM) and by labeling for talin, vinculin and integrin beta 1 subunits. In addition, stress fibers were visible. When cells were allowed to spread for 1h...

  10. Inhibitors of protein kinase C

    Institute of Scientific and Technical Information of China (English)

    LIU Shiying; JIANG Yuyang; CAO Jian; LIU Feng; MA Li; ZHAO Yufen

    2005-01-01

    Protein kinase catalyzes the transfer of the γ-phosphoryl group from ATP to the hydroxyl groups of protein side chains, which plays critical roles in signal transduction pathways by transmitting extracellular signals across the plasma membrane and nuclear membrane to the destination sites in the cytoplasm and the nucleus. Protein kinase C (PKC) is a superfamily of phospholipid-dependent Ser/Thr kinase. There are at least 12 isozymes in PKC family. They are distributed in different tissues and play different roles in physiological processes. On account of their concern with a variety of pathophysiologic states, such as cancer, inflammatory conditions, autoimmune disorder, and cardiac diseases, the inhibitors, which can inhibit the activity of PKC and the interaction of cytokine with receptor, and interfere signal transduction pathway, may be candidates of therapeutic drugs. Therefore, intense efforts have been made to develop specific protein kinase inhibitors as biological tools and therapeutic agents. This article reviews the recent development of some of PKC inhibitors based on their interaction with different conserved domains and different inhibition mechanisms.

  11. Adhesion of ZAP-70+ chronic lymphocytic leukemia cells to stromal cells is enhanced by cytokines and blocked by inhibitors of the PI3-kinase pathway.

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    Lafarge, Sandrine T; Johnston, James B; Gibson, Spencer B; Marshall, Aaron J

    2014-01-01

    CLL cell survival and proliferation is enhanced through direct contact with supporting cells present in lymphoid tissues. PI3Ks are critical signal transduction enzymes controlling B cell survival and activation. PI3K inhibitors have entered clinical trials and show promising therapeutic activity; however, it is unclear whether PI3K inhibitor drugs differentially affect ZAP-70 positive versus negative CLL cells or target specific microenvironmental interactions. Here we provide evidence that CD40L+IL-4, IL-8 or IL-6 enhance adhesion to stromal cells, with IL-6 showing a selective effect on ZAP-70 positive cells. Stimulatory effects of IL-8 or IL-6 are fully reversed by PI3K inhibition, while the effects of CD40L+IL-4 are partially reversed. While CD40L+IL-4 is the only stimulation increasing CLL cell survival for all patient groups, IL-6 protects ZAP-70 positive cells from cell death induced by PI3K inhibition. Altogether, our results indicate that targeting the PI3K pathway can reverse protective CLL-microenvironment interactions in both ZAP-70 positive and negative CLL despite their differences in cytokine responsiveness.

  12. Kinase inhibitors for advanced medullary thyroid carcinoma

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    Martin Schlumberger

    2012-01-01

    Full Text Available The recent availability of molecular targeted therapies leads to a reconsideration of the treatment strategy for patients with distant metastases from medullary thyroid carcinoma. In patients with progressive disease, treatment with kinase inhibitors should be offered.

  13. Conformation-specific inhibitors of Raf kinases.

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    Wang, Xiaolun; Schleicher, Kristin

    2013-01-01

    Since the discovery linking B-Raf mutations to human tumors in 2002, significant advances in the development of Raf inhibitors have been made, leading to the recent approval of two Raf inhibitor drugs. This chapter includes a brief introduction to B-Raf as a validated target and focuses on the three different binding modes observed with Raf small-molecule inhibitors. These various binding modes lock the Raf kinase in different conformations that impact the toxicity profiles of the inhibitors. Possible solutions to mitigate the side effects caused by inhibitor-induced dimerization are also discussed.

  14. Aurora kinase inhibitors: current status and outlook

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    Vassilios eBavetsias

    2015-12-01

    Full Text Available The Aurora kinase family comprises of cell cycle-regulated serine/threonine kinases important for mitosis. Their activity and protein expression are cell cycle regulated, peaking during mitosis to orchestrate important mitotic processes including centrosome maturation, chromosome alignment, chromosome segregation and cytokinesis. In humans, the Aurora kinase family consists of three members; Aurora-A, Aurora-B and Aurora-C, that each share a conserved C-terminal catalytic domain but differ in their sub-cellular localization, substrate specificity and function during mitosis. In addition, Aurora-A and Aurora-B have been found to be overexpressed in a wide variety of human tumors. These observations led to a number of programs among academic and pharmaceutical organizations to discovering small molecule Aurora kinase inhibitors as anti-cancer drugs. This review will summarize the known Aurora kinase inhibitors currently in the clinic and the current and future directions.

  15. Janus kinase inhibitors: jackpot or potluck?

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    Pavithran Keechilat

    2012-06-01

    Full Text Available The reports of a unique mutation in the Janus kinase-2 gene (JAK2 in polycythemia vera by several independent groups in 2005 quickly spurred the development of the Janus kinase inhibitors. In one of the great victories of translational research in recent times, the first smallmolecule Janus kinase inhibitor ruxolitinib entered a phase I trial in 2007. With the approval of ruxolitinib by the US Federal Drug Administration in November 2011 for high-risk and intermediate-2 risk myelofibrosis, a change in paradigm has occurred in the management of a subset of myeloproliferative neoplasms (MPN: primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Whereas the current evidence for ruxolitinib only covers high-risk and intermediate-2 risk myelofibrosis, inhibitors with greater potency are likely to offer better disease control and survival advantage in patients belonging to these categories, and possibly to the low-risk and intermediate-1 risk categories of MPN as well. But use of the Janus kinase inhibitors also probably has certain disadvantages, such as toxicity, resistance, withdrawal phenomenon, non-reversal of histology, and an implausible goal of disease clone eradication, some of which could offset the gains. In spite of this, Janus kinase inhibitors are here to stay, and for use in more than just myeloproliferative neoplasms.

  16. Serine34 phosphorylation of RHO guanine dissociation inhibitor (RHOGDI{alpha}) links signaling from conventional protein kinase C to RHO GTPase in cell adhesion

    DEFF Research Database (Denmark)

    Dovas, Athanassios; Choi, Youngsil; Yoneda, Atsuko;

    2010-01-01

    . Phosphospecific antibodies reveal endogenous phosphorylation in several cell types that is sensitive to adhesion events triggered, for example, by hepatocyte growth factor. Phosphorylation is also sensitive to PKC inhibition. Together with FRET microscopy sensing GTP-RhoA levels, the data reveal a common pathway......, resulting in a specific decrease in affinity for RhoA, but not Rac1 or cdc42. The mechanism of RhoGDIalpha phosphorylation is distinct, requiring PKCalpha and phosphatidylinositol 4,5 bisphosphate, consistent with recent evidence that the inositide can activate, localize and orient PKCalpha in membranes...

  17. Rational design of protein kinase inhibitors

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    Yarmoluk S. M.

    2013-07-01

    Full Text Available Modern methodological approaches to rational design of low molecular weight compounds with specific activity in relation to predetermined biomolecular targets are considered by example of development of high effective protein kinase inhibitors. The application of new computational methods that allow to significantly improve the quality of computational experiments (in, particular, accuracy of low molecular weight compounds activity prediction without increase of computational and time costs are highlighted. The effectiveness of strategy of rational design is demonstrated by examples of several own investigations devoted to development of new inhibitors that are high effective and selective towards protein kinases CK2, FGFR1 and ASK1.

  18. Discovery of inhibitors of bacterial histidine kinases

    NARCIS (Netherlands)

    Velikova, N.R.

    2014-01-01

    Discovery of Inhibitors of Bacterial Histidine Kinases

    Summary

    The thesis is on novel antibacterial drug discovery (http://youtu.be/NRMWOGgeysM). Using structure-based and fragment-based dru

  19. Tyrosine kinase inhibitors in hematological malignancies

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    Kamila Kosior

    2011-12-01

    Full Text Available Recently novel treatment modalities has focused on targeted therapies. Tyrosine kinases represent a good target for cancer treatment since they are involved in transferring phosphate groups from ATP to tyrosine residues in specific substrate proteins transducing intracellular signals engaged in the many mechanisms, playing an important role in the modulation of growth factors signaling that are strongly related to carcinogenesis. Deregulation of tyrosine kinases activity was also found in hematological malignancies, particularly overexpression of tyrosine kinases was observed in chronic myeloid leukemia or acute lymphoblastic leukemia. Herein we show that tyrosine kinase inhibitors have revolutionized hematology malignancies therapy in a very short period of time and they still remain one of the most interesting anticancer compounds that could give a hope for cure and not only long-lasting complete remission. This manuscript summarizes current view on the first generation tyrosine kinase inhibititor – imatinib, second generation – dasatinib, nilotinib and bosutnib as well as new generation tyrosine kinase inhibititors – ponatinib and danusertib in hematooncology.

  20. Recent advances in designing substrate-competitive protein kinase inhibitors.

    Science.gov (United States)

    Han, Ki-Cheol; Kim, So Yeon; Yang, Eun Gyeong

    2012-01-01

    Protein kinases play central roles in cellular signaling pathways and their abnormal phosphorylation activity is inseparably linked with various human diseases. Therefore, modulation of kinase activity using potent inhibitors is an attractive strategy for the treatment of human disease. While most protein kinase inhibitors in clinical development are mainly targeted to the highly conserved ATP-binding sites and thus likely promiscuously inhibit multiple kinases including kinases unrelated to diseases, protein substrate-competitive inhibitors are more selective and expected to be promising therapeutic agents. Most substrate-competitive inhibitors mimic peptides derived from substrate proteins, or from inhibitory domains within kinases or inhibitor proteins. In addition, bisubstrate inhibitors are generated by conjugating substrate-competitive peptide inhibitors to ATP-competitive inhibitors to improve affinity and selectivity. Although structural information on protein kinases provides invaluable guidance in designing substrate-competitive inhibitors, other strategies including bioinformatics, computational modeling, and high-throughput screening are often employed for developing specific substrate-competitive kinase inhibitors. This review focuses on recent advances in the design and discovery of substrate-competitive inhibitors of protein kinases.

  1. Janus kinase inhibitors for rheumatoid arthritis.

    Science.gov (United States)

    Yamaoka, Kunihiro

    2016-06-01

    Treatment of autoimmune diseases, such as rheumatoid arthritis (RA), has advanced substantially over the past decade with the development of biologics targeting inflammatory cytokines. Recent progress in treating RA has been achieved with janus kinase (JAK) inhibitors (Jakinibs), an orally available disease-modifying anti-rheumatic drug targeting the intracellular kinase JAK and with similar efficacy to biologics. The first Jakinib approved for RA was tofacitinib, which exerted superiority to methotrexate and non-inferiority to tumor necrosis factor (TNF) inhibitors. In recent years, the Jakinib baricitinib has demonstrated superiority to both methotrexate and a TNF inhibitor, adalimumab. Given these promising findings, Jakinibs are expected to represent the next generation compounds for treating RA, and a number of Jakinibs are currently in clinical trials. Jakinibs can differ substantially in their selectivity against JAKs; tofacitinib and baricitinib target multiple JAKs, whereas the most recently developed Jakinibs target only a single JAK. The influence of Jakinib selectivity on efficacy and side effects is of great interest, requiring further careful observation. PMID:26994322

  2. Bisarylmaleimides & the Corresponding Indolocarbazoles as Kinase Inhibitors

    Institute of Scientific and Technical Information of China (English)

    Zhu Guoxin; Cathy Ogg; Bharvin Patel; Richard M. Schultz; Charles D. Spencer; Beverly Teicher; Scou A. Watkins; Scott E. Conner; Zhou Xun; Chuan Shih; Li Tiechao; Harold B. Brooks; Eileen Considine; Jack A. Dempsey; Margaret M. Faul

    2004-01-01

    Cyclin dependent kinases (CDKs) have recently raised considerable attention because of their central role in the regulation of cell cycle progression. A high incidence of genetic mutation of CDK substrates and deregulaton of CDK modulators were found in a number of disease states,particularly in cancer. A novel series of unsymmetrical substituted indolocarbazoles were synthesized and their kinase inhibitory capability was evaluated in vitro. 6-Substtuted indolocarbazoles were found to be highly potent and selective D1/CDK4 inhibitors. These indolocarbazoles exhibited ATP competitive D1/CDK4 activity and inhibited tumor cell growth,arrested tumor cell at G1 phase. These molecules demonstrated potent anti-tumor activity and inhibited pRb phosphorylation at S780 in the human lung carcinoma (Calu6) and non-small cell lung carcinoma (NCI-H460) xenograft models. The results indicate that these small molecules have potential as therapeutic agents in cancer chemotherapeutc agents.

  3. Structural investigation of protein kinase C inhibitors

    Science.gov (United States)

    Barak, D.; Shibata, M.; Rein, R.

    1991-01-01

    The phospholipid and Ca2+ dependent protein kinase (PKC) plays an essential role in a variety of cellular events. Inhibition of PKC was shown to arrest growth in tumor cell cultures making it a target for possible antitumor therapy. Calphostins are potent inhibitors of PKC with high affinity for the enzyme regulatory site. Structural characteristics of calphostins, which confer the inhibitory activity, are investigated by comparing their optimized structures with the existing models for PKC activation. The resulting model of inhibitory activity assumes interaction with two out of the three electrostatic interaction sites postulated for activators. The model shows two sites of hydrophobic interaction and enables the inhibitory activity of gossypol to be accounted for.

  4. Inherent formulation issues of kinase inhibitors.

    Science.gov (United States)

    Herbrink, M; Schellens, J H M; Beijnen, J H; Nuijen, B

    2016-10-10

    The small molecular Kinase Inhibitor (smKI) drug class is very promising and rapidly expanding. All of these drugs are administered orally. The clear relationship between structure and function has led to drugs with a general low intrinsic solubility. The majority of the commercial pharmaceutical formulations of the smKIs are physical mixtures that are limited by the low drug solubility of a salt form. This class of drugs is therefore characterized by an impaired and variable bioavailability rendering them costly and their therapies suboptimal. New formulations are sparingly being reported in literature and patents. The presented data suggests that continued research into formulation design can help to develop more efficient and cost-effective smKI formulation. Moreover, it may also be of help in the future design of the formulations of new smKIs.

  5. New Class of Competitive Inhibitor of Bacterial Histidine Kinases

    OpenAIRE

    Gilmour, Raymond; Foster, J. Estelle; Sheng, Qin; McClain, Jonathan R.; Riley, Anna; Sun, Pei-Ming; Ng, Wai-Leung; Yan, Dalai; Nicas, Thalia I.; Henry, Kenneth; Winkler, Malcolm E.

    2005-01-01

    Bacterial histidine kinases have been proposed as targets for the discovery of new antibiotics, yet few specific inhibitors of bacterial histidine kinases have been reported. We report here a novel thienopyridine (TEP) compound that inhibits bacterial histidine kinases competitively with respect to ATP but does not comparably inhibit mammalian serine/threonine kinases. Although it partitions into membranes and does not inhibit the growth of bacterial or mammalian cells, TEP could serve as a s...

  6. In Vitro Characterization of Derrone as an Aurora Kinase Inhibitor.

    Science.gov (United States)

    Hoang, Nhung Thi My; Phuong, Thuong Thien; Nguyen, Trang Thi Nhu; Tran, Yen Thi Hai; Nguyen, Anh Thi Ngoc; Nguyen, Thanh Lai; Bui, Khanh Thi Van

    2016-06-01

    Among mitotic kinases, Aurora kinases are the most widely studied, since their expression is restricted to mitosis. They play a key role in chromosome segregation and cell polyploidy. Aurora kinases are important therapeutic targets, and several research groups have directed their efforts toward the identification of kinase inhibitors. The aim of this study is to screen and characterize Aurora kinase inhibitors from natural substances extracted from plants that are used in the Vietnamese pharmacopoeia. We have characterized in vitro Derrone, extracted from Erythrina orientalis L. MURR, as a novel Aurora kinase inhibitor. This compound exhibited an ability to inhibit the phosphorylation of histone H3 at ser10 both in kinase assay and at the cellular level. The compound was more effective against Aurora kinase B, with a lower IC50 value as compared to Aurora A. Moreover, it impaired the mitotic spindle checkpoint and led to endoreduplication in cancer cells, a phenomenon caused by an Aurora B inhibitor. Interestingly, using the xCelligence system and real-time cell analysis (RTCA) software, we set up a comparison of cell proliferation profiles between cancer cells treated with Derrone and VX680-a well-known Aurora kinase inhibitor-and we found that these profiles exhibited considerable similarity in cell morphology, growth, and death. Additionally, Derrone significantly inhibited the formation and growth of MCF7 tumor spheroids. PMID:26983907

  7. Skin problems and EGFR-tyrosine kinase inhibitor.

    Science.gov (United States)

    Kozuki, Toshiyuki

    2016-04-01

    Epidermal growth factor receptor inhibition is a good target for the treatment of lung, colon, pancreatic and head and neck cancers. Epidermal growth factor receptor-tyrosine kinase inhibitor was first approved for the treatment of advanced lung cancer in 2002. Epidermal growth factor receptor-tyrosine kinase inhibitor plays an essential role in the treatment of cancer, especially for patients harbouring epidermal growth factor receptor activating mutation. Hence, skin toxicity is the most concerning issue for the epidermal growth factor receptor-tyrosine kinase inhibitor treatment. Skin toxicity is bothersome and sometimes affects the quality of life and treatment compliance. Thus, it is important for physicians to understand the background and how to manage epidermal growth factor receptor-tyrosine kinase inhibitor-associated skin toxicity. Here, the author reviewed the mechanism and upfront preventive and reactive treatments for epidermal growth factor receptor inhibitor-associated skin toxicities.

  8. MEK inhibitors, novel anti-adhesive molecules, reduce sickle red blood cell adhesion in vitro and in vivo, and vasoocclusion in vivo.

    Directory of Open Access Journals (Sweden)

    Rahima Zennadi

    Full Text Available In sickle cell disease, sickle erythrocyte (SSRBC interacts with endothelial cells, leukocytes, and platelets, and activates coagulation and inflammation, promoting vessel obstruction, which leads to serious life-threatening complications, including acute painful crises and irreversible damage to multiple organs. The mitogen-activated protein kinase, ERK1/2, is abnormally activated in SSRBCs. However, the therapeutic potential of SSRBC ERK1/2 inactivation has never been investigated. I tested four different inhibitors of MEK1/2 (MEK, the kinase that activates ERK1/2, in a model of human SSRBC adhesion to TNFα-activated endothelial cells (ECs. SSRBC MEK inhibition abrogated adhesion to non-activated and TNFα-activated ECs to levels below baseline SSRBC adhesion to non-activated ECs in vitro. SSRBC MEK inhibition also prevented SSRBCs from activating naïve neutrophils to adhere to endothelium. To determine the effect of MEK inhibitors on SSRBC adherence in vivo, sham-treated or MEK inhibitor-treated SSRBCs were infused to nude mice previously treated with TNFα. Sham-treated SSRBCs displayed marked adhesion and occlusion of enflamed vessels, both small and large. However, SSRBC treatment with MEK inhibitors ex vivo showed poor SSRBC adhesion to enflamed vessels with no visible vasoocclusion in vivo. In addition, MEK inhibitor treatment of SSRBCs reduced SSRBC organ trapping and increased the number of SSRBCs circulating in bloodstream. Thus, these data suggest that SSRBC ERK1/2 plays potentially a critical role in sickle pathogenesis, and that MEK inhibitors may represent a valuable intervention for acute sickle cell crises.

  9. Recent Developments of Protein Kinase Inhibitors as Potential AD Therapeutics

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    Andreas eHilgeroth

    2013-11-01

    Full Text Available Present AD therapies suffer from inefficient effects on AD symptoms like memory or cognition, especially in later states of the disease. Used acteylcholine esterase (ACE inhibitors or the NMDA receptor antagonist memantine address one target structure which is involved in a complex, multifactorial disease progression. So the benefit for patients is presently poor. A more close insight in the AD progression identified more suggested target structures for drug development. Strategies of AD drug development concentrate on novel target structures combined with the established ones dedicated for combined therapy regimes, preferably by the use of one drug which may address two target structures. Protein kinases have been identified as promising target structures because they are involved in AD progression pathways like pathophysiological tau protein phosphorylations and amyloid β toxicity. The review article will shortly view early inhibitors of single protein kinases like glycogen synthase kinase (gsk3 β and cyclin dependent kinase 5. Novel inhibitors will be discussed which address novel AD relevant protein kinases like dual-specifity tyrosine phosphorylation regulated kinase 1A (DYRK1A. Moreover, multitargeting inhibitors will be presented which target several protein kinases and those which are suspected in influencing other AD relevant processes. Such a multitargeting is the most promising strategy to effectively hamper the multifactorial disease progression and thus gives perspective hopes for a future better patient benefit.

  10. Kinase inhibitors: a new class of antirheumatic drugs

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    Kyttaris VC

    2012-09-01

    Full Text Available Vasileios C KyttarisDivision of Rheumatology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USAAbstract: The outlook for patients with rheumatoid arthritis has improved significantly over the last three decades with the use of disease-modifying antirheumatic drugs. However, despite the use of methotrexate, cytokine inhibitors, and molecules targeting T and B cells, a percentage of patients do not respond or lose their response over time. The autoimmune process in rheumatoid arthritis depends on activation of immune cells, which utilize intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. In the past decade, small molecules targeting several kinases, such as p38 MAPK, Syk, and JAK have been developed. Several p38 MAPK inhibitors proved ineffective in treating rheumatoid arthritis. The Syk inhibitor, fostamatinib, proved superior to placebo in Phase II trials and is currently under Phase III investigation. Tofacitinib, a JAK1/3 inhibitor, was shown to be efficacious in two Phase III trials, while VX-509, a JAK3 inhibitor, showed promising results in a Phase II trial. Fostamatinib and tofacitinib were associated with increased rates of infection, elevation of liver enzymes, and neutropenia. Moreover, fostamatinib caused elevations of blood pressure and diarrhea, while tofacitinib was associated with an increase in creatinine and elevation of lipid levels.Keywords: rheumatoid arthritis, kinase inhibitors, mitogen-activated phosphokinase p38, spleen tyrosine kinase, Janus kinases

  11. The Aurora kinase inhibitors in cancer research and therapy.

    Science.gov (United States)

    Cicenas, Jonas

    2016-09-01

    Compounds that affect enzymatic function of kinases are valuable for the understanding of the complex biochemical processes in cells. Aurora kinases (AURKs) play a key role in the control of the mitosis. These kinases are frequently deregulated in different human cancers: overexpression, amplifications, translocations and deletions were reported in many cancer cell lines as well as patient tissues. These findings steered a rigorous hunt for small-molecule AURK inhibitors not only for research purposes as well as for therapeutic uses. In this review, we describe a number of AURK inhibitors and their use in cancer research and/or therapy. We hope to assist researchers and clinicians in deciding which inhibitor is most appropriate for their specific purpose. The review will also provide a broad overview of the clinical studies performed with some of these inhibitors (if such studies have been performed). PMID:26932147

  12. Pyrrolopyridine inhibitors of mitogen-activated protein kinase-activated protein kinase 2 (MK-2).

    Science.gov (United States)

    Anderson, David R; Meyers, Marvin J; Vernier, William F; Mahoney, Matthew W; Kurumbail, Ravi G; Caspers, Nicole; Poda, Gennadiy I; Schindler, John F; Reitz, David B; Mourey, Robert J

    2007-05-31

    A new class of potent kinase inhibitors selective for mitogen-activated protein kinase-activated protein kinase 2 (MAPKAP-K2 or MK-2) for the treatment of rheumatoid arthritis has been prepared and evaluated. These inhibitors have IC50 values as low as 10 nM against the target and have good selectivity profiles against a number of kinases including CDK2, ERK, JNK, and p38. These MK-2 inhibitors have been shown to suppress TNFalpha production in U397 cells and to be efficacious in an acute inflammation model. The structure-activity relationships of this series, the selectivity for MK-2 and their activity in both in vitro and in vivo models are discussed. The observed selectivity is discussed with the aid of an MK-2/inhibitor crystal structure.

  13. IL-12 and IL-18 induce MAP kinase-dependent adhesion of T cells to extracellular matrix components.

    Science.gov (United States)

    Ariel, Amiram; Novick, Daniela; Rubinstein, Menachem; Dinarello, Charles A; Lider, Ofer; Hershkoviz, Rami

    2002-07-01

    Cytokines and chemokines play an essential role in recruiting leukocytes from the circulation to the peripheral sites of inflammation by modulating cellular interactions with endothelial cell ligands and extracellular matrix (ECM). Herein, we examined regulation of T cell adhesion to ECM ligands by two major proinflammatory cytokines, interleukin (IL)-12 and IL-18. IL-12 and IL-18 induced T cell adhesion to fibronectin (FN) and hyaluronic acid at low (pM) concentrations that were mediated by specific adhesion molecules expressed on the T cell surface, namely, beta(1) integrins and CD44, respectively. The induction of adhesion by IL-12 and IL-18 was inhibited by extracellular signal-regulated kinase and p38 mitogen-activated protein kinase inhibitors (PD098059 and SB203580, respectively). In contrast, IL-12- and IL-18-induced interferon-gamma (INF-gamma) secretion from T cells was inhibited by SB203580, but not by PD098059. It is interesting that low concentrations of IL-12 and IL-18 induced T cell adhesion to FN in a synergistic manner. Thus, in addition to the regulation of late inflammatory functions such as INF-gamma production, IL-12 and IL-18, alone or in combination, regulate early inflammatory events such as T cell adhesion to inflamed sites. PMID:12101280

  14. Design, Synthesis and Inhibitory Activity of Photoswitchable RET Kinase Inhibitors

    Science.gov (United States)

    Ferreira, Rubén; Nilsson, Jesper R.; Solano, Carlos; Andréasson, Joakim; Grøtli, Morten

    2015-05-01

    REarranged during Transfection (RET) is a transmembrane receptor tyrosine kinase required for normal development and maintenance of neurons of the central and peripheral nervous systems. Deregulation of RET and hyperactivity of the RET kinase is intimately connected to several types of human cancers, most notably thyroid cancers, making it an attractive therapeutic target for small-molecule kinase inhibitors. Novel approaches, allowing external control of the activity of RET, would be key additions to the signal transduction toolbox. In this work, photoswitchable RET kinase inhibitors based on azo-functionalized pyrazolopyrimidines were developed, enabling photonic control of RET activity. The most promising compound displays excellent switching properties and stability with good inhibitory effect towards RET in cell-free as well as live-cell assays and a significant difference in inhibitory activity between its two photoisomeric forms. As the first reported photoswitchable small-molecule kinase inhibitor, we consider the herein presented effector to be a significant step forward in the development of tools for kinase signal transduction studies with spatiotemporal control over inhibitor concentration in situ.

  15. Novel Phosphotidylinositol 4,5-Bisphosphate Binding Sites on Focal Adhesion Kinase

    OpenAIRE

    Jun Feng; Blake Mertz

    2015-01-01

    Focal adhesion kinase (FAK) is a protein tyrosine kinase that is ubiquitously expressed, recruited to focal adhesions, and engages in a variety of cellular signaling pathways. Diverse cellular responses, such as cell migration, proliferation, and survival, are regulated by FAK. Prior to activation, FAK adopts an autoinhibited conformation in which the FERM domain binds the kinase domain, blocking access to the activation loop and substrate binding site. Activation of FAK occurs through confor...

  16. Allosteric small-molecule kinase inhibitors

    DEFF Research Database (Denmark)

    Wu, Peng; Clausen, Mads Hartvig; Nielsen, Thomas E.

    2015-01-01

    -molecule allosteric inhibitor trametinib in 2013, the progress of more than 10 other allosteric inhibitors in clinical trials, and the emergence of a pipeline of highly selective and potent preclinical molecules, have been reported in the past decade. In this article, we present the current knowledge on allosteric...

  17. The Azaindole Framework in the Design of Kinase Inhibitors

    OpenAIRE

    Jean-Yves Mérour; Frédéric Buron; Karen Plé; Pascal Bonnet; Sylvain Routier

    2014-01-01

    This review article illustrates the growing use of azaindole derivatives as kinase inhibitors and their contribution to drug discovery and innovation. The different protein kinases which have served as targets and the known molecules which have emerged from medicinal chemistry and Fragment-Based Drug Discovery (FBDD) programs are presented. The various synthetic routes used to access these compounds and the chemical pathways leading to their synthesis are also discussed. An analysis of their ...

  18. Phospho-kinase profile of colorectal tumors guides in the selection of multi-kinase inhibitors.

    Science.gov (United States)

    Serrano-Heras, Gemma; Cuenca-López, María Dolores; Montero, Juan Carlos; Corrales-Sanchez, Verónica; Morales, Jorge Carlos; Núñez, Luz-Elena; Morís, Francisco; Pandiella, Atanasio; Ocaña, Alberto

    2015-10-13

    Protein kinases play a central role in the oncogenesis of colorectal tumors and are attractive druggable targets. Detection of activated kinases within a tumor could open avenues for drug selection and optimization of new kinase inhibitors. By using a phosphokinase arrays with human colorectal tumors we identified activated kinases, including the Epidermal Growth Factor Receptor (EGFR), components of the PI3K/mTOR pathway (AKT and S6), and STAT, among others. A pharmacological screening with kinase inhibitors against these proteins helped us to identify a new kinase inhibitor, termed EC-70124 that showed the highest anti-proliferative activity in cell lines. EC-70124 also inhibited cell migration and biochemical experiments demonstrated its effect targeting the PI3K/mTOR pathway. This drug also arrested cells at G2/M and induced apoptosis. Experiments in combination with standard chemotherapy used in the clinical setting indicated a synergistic effect. EC-70124 also reduced tumor growth in vivo and inhibited pS6 in the implanted tumors. In conclusion, by studying the kinase profile of colorectal tumors, we identified relevant activated pathways, and a new multi-kinase compound with significant antitumor properties. PMID:26418718

  19. Protein kinase C, focal adhesions and the regulation of cell migration

    DEFF Research Database (Denmark)

    Fogh, Betina S; Multhaupt, Hinke A B; Couchman, John Robert

    2014-01-01

    and adhesion turnover. Focal adhesions, or focal contacts, are widespread organelles at the cell-matrix interface. They arise as a result of receptor interactions with matrix ligands, together with clustering. Recent analysis shows that focal adhesions contain a very large number of protein components......Cell adhesion to extracellular matrix is a complex process involving protrusive activity driven by the actin cytoskeleton, engagement of specific receptors, followed by signaling and cytoskeletal organization. Thereafter, contractile and endocytic/recycling activities may facilitate migration...... in their intracellular compartment. Among these are tyrosine kinases, which have received a great deal of attention, whereas the serine/threonine kinase protein kinase C has received much less. Here the status of protein kinase C in focal adhesions and cell migration is reviewed, together with discussion of its roles...

  20. Side-effects of protein kinase inhibitors on ion channels

    Indian Academy of Sciences (India)

    Youn Kyoung Son; Hongzoo Park; Amy L Firth; Won Sun Park

    2013-12-01

    Protein kinases are one of the largest gene families and have regulatory roles in all aspects of eukaryotic cell function. Modulation of protein kinase activity is a desirable therapeutic approach for a number of human diseases associated with aberrant kinase activity, including cancers, arthritis and cardiovascular disorders. Several strategies have been used to develop specific and selective protein kinase modulators, primarily via inhibition of phosphorylation and down-regulation of kinase gene expression. These strategies are effective at regulating intracellular signalling pathways, but are unfortunately associated with several undesirable effects, particularly those that modulate ion channel function. In fact, the side-effects have precluded these inhibitors from being both useful experimental tools and therapeutically viable. This review focuses on the ion channel side-effects of several protein kinase inhibitors and specifically on those modulating K+, Na+ and Ca2+ ion channels. It is hoped that the information provided with a detailed summary in this review will assist the future development of novel specific and selective compounds targeting protein kinases both for experimental tools and for therapeutic approaches.

  1. Versatile templates for the development of novel kinase inhibitors: Discovery of novel CDK inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Michael P.; Paruch, Kamil; Alvarez, Carmen; Doll, Ronald J.; Keertikar, Kerry; Duca, Jose; Fischmann, Thierry O.; Hruza, Alan; Madison, Vincent; Lees, Emma; Parry, David; Seghezzi, Wolfgang; Sgambellone, Nicole; Shanahan, Frances; Wiswell, Derek; Guzi, Timothy J. (SPRI)

    2008-06-30

    A series of four bicyclic cores were prepared and evaluated as cyclin-dependent kinase-2 (CDK2) inhibitors. From the in-vitro and cell-based analysis, the pyrazolo[1,5-a]pyrimidine core (represented by 9) emerged as the superior core for further elaboration in the identification of novel CDK2 inhibitors.

  2. Quinazolines as cyclin dependent kinase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sielecki, Thais M.; Johnson, Tricia L.; Liu, Jie; Muckelbauer, Jodi K.; Grafstrom, Robert H.; Cox, Sarah; Boylan, John; Burton, Catherine R.; Chen, Haiying; Smallwood, Angela; Chang, Chong-Hwan; Boisclair, Michael; Benfield, Pamela A.; Trainor, George L.; Seitza, Steven P. (Dupont)

    2010-03-08

    Quinazolines have been identified as inhibitors of CDK4/D1 and CDK2/E. Aspects of the SAR were investigated using solution-phase, parallel synthesis. An X-ray crystal structure was obtained of quinazoline 51 bound in CDK2 and key interactions within the ATP binding pocket are defined.

  3. Old Tyrosine Kinase Inhibitors and Newcomers in Gastrointestinal Cancer Treatment.

    Science.gov (United States)

    Erika, Giordani; Federica, Zoratto; Martina, Strudel; Anselmo, Papa; Luigi, Rossi; Marina, Minozzi; Davide, Caruso; Eleonora, Zaccarelli; Monica, Verrico; Silverio, Tomao

    2016-01-01

    Gastrointestinal cancer treatment is based more on molecular biology that has provided increasing knowledge about cancer pathogenesis on which targeted therapy is being developed. Precisely, targeted therapy is defined as a "type of treatment that uses drugs, such as monoclonal antibodies or tyrosine kinase inhibitors, to identify and attack specific cancer cells". Nowadays, the United States Food and Drug Administration has approved many targeted therapies for gastrointestinal cancer treatment, as many are in various phases of development as well. In a previous review we discussed the main monoclonal antibodies used and studied in gastrointestinal cancer. In addition to monoclonal antibodies, tyrosine kinase inhibitors represent another class of targeted therapy and following the approval of imatinib for gastrointestinal stromal tumours, other tyrosine kinase inhibitors have been approved for gastrointestinal cancers treatment such as sunitinib, regoragenib, sorafenib and erlotinib. Moving forward, the purpose of this review is to focus on the efficacy data of main tyrosine kinase inhibitors commonly used in the personalized treatment of each gastrointestinal tumour and to provide a comprehensive overview about experimental targeted therapies ongoing in this setting. PMID:26278713

  4. JAK kinase inhibitors for the treatment of acute lymphoblastic leukemia

    OpenAIRE

    Degryse, Sandrine; Cools, Jan

    2015-01-01

    Recent studies of acute lymphoblastic leukemia have identified activating mutations in components of the interleukin-7 receptor complex (IL7R, JAK1, and JAK3). It will be of interest to investigate both JAK1 and JAK3 kinase inhibitors as targeted agents for these leukemias.

  5. Molecular pharmacokinetic determinants of anticancer kinase inhibitors in humans

    Directory of Open Access Journals (Sweden)

    Julie Scholler

    2011-06-01

    Full Text Available This review presents the published data regarding the molecular determinants (drug metabolizing enzymes, drug transporters and orphan nuclear receptors of approved anticancer kinase inhibitors pharmacokinetics in humans. The clinical impact of these determinants (drug disposition and drug–drug interactions is also discussed.

  6. Searching Inhibitors of Adenosine Kinase by Simulation Methods

    Institute of Scientific and Technical Information of China (English)

    ZHU Rui-Xin; ZHANG Xing-Long; DONG Xi-Cheng; CHEN Min-Bo

    2006-01-01

    Searching new inhibitors of adenosine kinase (AK) is still drawing attention of experimental scientists. A better and solid model is here proposed by means of simulation methods from different ways, the direct analysis of receptor itself, the conventional 3D-QSAR methods and the integration of docking method and the conventional QSAR analysis.

  7. Old Tyrosine Kinase Inhibitors and Newcomers in Gastrointestinal Cancer Treatment.

    Science.gov (United States)

    Giordani, Erika; Zoratto, Federica; Strudel, Martina; Papa, Anselmo; Rossi, Luigi; Minozzi, Marina; Caruso, Davide; Zaccarelli, Eleonora; Verrico, Monica; Tomao, Silverio

    2016-01-01

    Gastrointestinal cancer treatment is based more on molecular biology that has provided increasing knowledge about cancer pathogenesis on which targeted therapy is being developed. Precisely, targeted therapy is defined as a "type of treatment that uses drugs, such as monoclonal antibodies or tyrosine kinase inhibitors, to identify and attack specific cancer cells". Nowadays, the United States Food and Drug Administration has approved many targeted therapies for gastrointestinal cancer treatment, as many are in various phases of development as well. In a previous review we discussed the main monoclonal antibodies used and studied in gastrointestinal cancer. In addition to monoclonal antibodies, tyrosine kinase inhibitors represent another class of targeted therapy and following the approval of imatinib for gastrointestinal stromal tumours, other tyrosine kinase inhibitors have been approved for gastrointestinal cancers treatment such as sunitinib, regoragenib, sorafenib and erlotinib. Moving forward, the purpose of this review is to focus on the efficacy data of main tyrosine kinase inhibitors commonly used in the personalized treatment of each gastrointestinal tumour and to provide a comprehensive overview about experimental targeted therapies ongoing in this setting.

  8. Opportunities to Target Specific Contractile Abnormalities with Smooth Muscle Protein Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Annegret Ulke-Lemée

    2010-05-01

    Full Text Available Smooth muscle is a major component of most hollow organ systems (e.g., airways, vasculature, bladder and gut/gastrointestine; therefore, the coordinated regulation of contraction is a key property of smooth muscle. When smooth muscle functions normally, it contributes to general health and wellness, but its dysfunction is associated with morbidity and mortality. Rho-associated protein kinase (ROCK is central to calcium-independent, actomyosin-mediated contractile force generation in the vasculature, thereby playing a role in smooth muscle contraction, cell motility and adhesion. Recent evidence supports an important role for ROCK in the increased vasoconstriction and remodeling observed in various models of hypertension. This review will provide a commentary on the development of specific ROCK inhibitors and their clinical application. Fasudil will be discussed as an example of bench-to-bedside development of a clinical therapeutic that is used to treat conditions of vascular hypercontractility. Due to the wide spectrum of biological processes regulated by ROCK, many additional clinical indications might also benefit from ROCK inhibition. Apart from the importance of ROCK in smooth muscle contraction, a variety of other protein kinases are known to play similar roles in regulating contractile force. The zipper-interacting protein kinase (ZIPK and integrin-linked kinase (ILK are two well-described regulators of contraction. The relative contribution of each kinase to contraction depends on the muscle bed as well as hormonal and neuronal stimulation. Unfortunately, specific inhibitors for ZIPK and ILK are still in the development phase, but the success of fasudil suggests that inhibitors for these other kinases may also have valuable clinical applications. Notably, the directed inhibition of ZIPK with a pseudosubstrate molecule shows unexpected effects on the contractility of gastrointestinal smooth muscle.

  9. Octahedral ruthenium complexes as protein kinase inhibitors

    OpenAIRE

    Li FENG

    2010-01-01

    Die vorliegende Arbeit beschäftigt sich mit einer Strategie zur Darstellung von selektiven Proteinkinaseinhibitoren unter Verwendung starrer, oktaedrischer Rutheniumkomplexe als Strukturmerkmal. Nanomolare Inhibitoren für die Proteinkinasen PAK1, MLCK und DAPK1, sowie ein picomolarer Inhibitor für die Proteinkinase Pim1 wurden entwickelt. Diese Inhibitoren weisen eine außerordentlich hohe Selektivität gegenüber den anderen ...

  10. Predictive Models for Fast and Effective Profiling of Kinase Inhibitors.

    Science.gov (United States)

    Bora, Alina; Avram, Sorin; Ciucanu, Ionel; Raica, Marius; Avram, Stefana

    2016-05-23

    In this study we developed two-dimensional pharmacophore-based random forest models for the effective profiling of kinase inhibitors. One hundred seven prediction models were developed to address distinct kinases spanning over all kinase groups. Rigorous external validation demonstrates excellent virtual screening and classification potential of the predictors and, more importantly, the capacity to prioritize novel chemical scaffolds in large chemical libraries. The models built upon more diverse and more potent compounds tend to exert the highest predictive power. The analysis of ColBioS-FlavRC (Collection of Bioselective Flavonoids and Related Compounds) highlighted several potentially promiscuous derivatives with undesirable selectivity against kinases. The prediction models can be downloaded from www.chembioinf.ro . PMID:27064988

  11. Combinations of Kinase Inhibitors Protecting Myoblasts against Hypoxia.

    Directory of Open Access Journals (Sweden)

    Yunyi Kang

    Full Text Available Cell-based therapies to treat skeletal muscle disease are limited by the poor survival of donor myoblasts, due in part to acute hypoxic stress. After confirming that the microenvironment of transplanted myoblasts is hypoxic, we screened a kinase inhibitor library in vitro and identified five kinase inhibitors that protected myoblasts from cell death or growth arrest in hypoxic conditions. A systematic, combinatorial study of these compounds further improved myoblast viability, showing both synergistic and additive effects. Pathway and target analysis revealed CDK5, CDK2, CDC2, WEE1, and GSK3β as the main target kinases. In particular, CDK5 was the center of the target kinase network. Using our recently developed statistical method based on elastic net regression we computationally validated the key role of CDK5 in cell protection against hypoxia. This method provided a list of potential kinase targets with a quantitative measure of their optimal amount of relative inhibition. A modified version of the method was also able to predict the effect of combinations using single-drug response data. This work is the first step towards a broadly applicable system-level strategy for the pharmacology of hypoxic damage.

  12. Focal adhesion kinase overexpression and its impact on human osteosarcoma

    Science.gov (United States)

    Chen, Yong; Yang, Aizhen; Chen, Hui; Zhang, Jian; Wu, Sujia; Shi, Xin; Wang, Chen; Sun, Xiaoliang

    2015-01-01

    Focal adhesion kinase (FAK) has been implicated in tumorigenesis in various malignancies. We sought to examine the expression patterns of FAK and the activated form, phosphorylated FAK (pFAK), in human osteosarcoma and to investigate the correlation of FAK expression with clinicopathologic parameters and prognosis. In addition, the functional consequence of manipulating the FAK protein level was investigated in human osteosarcoma cell lines. Immunohistochemical staining was used to detect FAK and pFAK in pathologic archived materials from 113 patients with primary osteosarcoma. Kaplan-Meier survival and Cox regression analyses were performed to evaluate the prognoses. The role of FAK in the cytological behavior of MG63 and 143B human osteosarcoma cell lines was studied via FAK protein knock down with siRNA. Cell proliferation, migration, invasiveness and apoptosis were assessed using the CCK8, Transwell and Annexin V/PI staining methods. Both FAK and pFAK were overexpressed in osteosarcoma. There were significant differences in overall survival between the FAK-/pFAK- and FAK+/pFAK- groups (P = 0.016), the FAK+/pFAK- and FAK+/pFAK+ groups (P = 0.012) and the FAK-/pFAK- and FAK+/pFAK+ groups (P < 0.001). There were similar differences in metastasis-free survival between groups. The Cox proportional hazards analysis showed that the FAK expression profile was an independent indicator of both overall and metastasis-free survival. siRNA-based knockdown of FAK not only dramatically reduced the migration and invasion of MG63 and 143B cells, but also had a distinct effect on osteosarcoma cell proliferation and apoptosis. These results collectively suggest that FAK overexpression and phosphorylation might predict more aggressive biologic behavior in osteosarcoma and may be an independent predictor of poor prognosis. PMID:26393679

  13. Structure-guided discovery of cyclin-dependent kinase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Fischmann, Thierry O.; Hruza, Alan; Duca, Jose S.; Ramanathan, Lata; Mayhood, Todd; Windsor, William T.; Le, Hung V.; Guzi, Timothy J.; Dwyer, Michael P.; Paruch, Kamil; Doll, Ronald J.; Lees, Emma; Parry, David; Seghezzi, Wolfgang; Madison, Vincent (SPRI)

    2008-10-02

    CDK2 inhibitors containing the related bicyclic heterocycles pyrazolopyrimidines and imidazopyrazines were discovered through high-throughput screening. Crystal structures of inhibitors with these bicyclic cores and two more related ones show that all but one have a common binding mode featuring two hydrogen bonds (H-bonds) to the backbone of the kinase hinge region. Even though ab initio computations indicated that the imidazopyrazine core would bind more tightly to the hinge, pyrazolopyrimidines gain an advantage in potency through participation of N4 in an H-bond network involving two catalytic residues and bridging water molecules. Further insight into inhibitor/CDK2 interactions was gained from analysis of additional crystal structures. Significant gains in potency were obtained by optimizing the fit of hydrophobic substituents to the gatekeeper region of the ATP binding site. The most potent inhibitors have good selectivity.

  14. Endocrine side effects of broad-acting kinase inhibitors.

    Science.gov (United States)

    Lodish, Maya B; Stratakis, Constantine A

    2010-09-01

    Targeted therapy in oncology consists of drugs that specifically interfere with abnormal signaling pathways that are dysregulated in cancer cells. Tyrosine kinase inhibitors (TKIs) take advantage of unique oncogenes that are activated in certain types of cancer, and also target common mechanisms of growth, invasion, metastasis, and angiogenesis. However, many kinase inhibitors for cancer therapy are somewhat nonselective, and most have additional mechanisms of action at the cellular level, which are not completely understood. The use of these agents has increased our knowledge of important side effects, of which the practicing clinician must be aware. Recently, proposed endocrine-related side effects of these agents include alterations in thyroid function, bone metabolism, linear growth, gonadal function, fetal development, and glucose metabolism, and adrenal function. This review summarizes the most recent data on the endocrine side effects of TKIs.

  15. Laminin α2-mediated focal adhesion kinase activation triggers Alport glomerular pathogenesis.

    Directory of Open Access Journals (Sweden)

    Duane Delimont

    Full Text Available It has been known for some time that laminins containing α1 and α2 chains, which are normally restricted to the mesangial matrix, accumulate in the glomerular basement membranes (GBM of Alport mice, dogs, and humans. We show that laminins containing the α2 chain, but not those containing the α1 chain activates focal adhesion kinase (FAK on glomerular podocytes in vitro and in vivo. CD151-null mice, which have weakened podocyte adhesion to the GBM rendering these mice more susceptible to biomechanical strain in the glomerulus, also show progressive accumulation of α2 laminins in the GBM, and podocyte FAK activation. Analysis of glomerular mRNA from both models demonstrates significant induction of MMP-9, MMP-10, MMP-12, MMPs linked to GBM destruction in Alport disease models, as well as the pro-inflammatory cytokine IL-6. SiRNA knockdown of FAK in cultured podocytes significantly reduced expression of MMP-9, MMP-10 and IL-6, but not MMP-12. Treatment of Alport mice with TAE226, a small molecule inhibitor of FAK activation, ameliorated fibrosis and glomerulosclerosis, significantly reduced proteinuria and blood urea nitrogen levels, and partially restored GBM ultrastructure. Glomerular expression of MMP-9, MMP-10 and MMP-12 mRNAs was significantly reduced in TAE226 treated animals. Collectively, this work identifies laminin α2-mediated FAK activation in podocytes as an important early event in Alport glomerular pathogenesis and suggests that FAK inhibitors, if safe formulations can be developed, might be employed as a novel therapeutic approach for treating Alport renal disease in its early stages.

  16. Phosphatidylinositol 3-kinase inhibitors block differentiation of skeletal muscle cells.

    Science.gov (United States)

    Kaliman, P; Viñals, F; Testar, X; Palacín, M; Zorzano, A

    1996-08-01

    Skeletal muscle differentiation involves myoblast alignment, elongation, and fusion into multinucleate myotubes, together with the induction of regulatory and structural muscle-specific genes. Here we show that two phosphatidylinositol 3-kinase inhibitors, LY294002 and wortmannin, blocked an essential step in the differentiation of two skeletal muscle cell models. Both inhibitors abolished the capacity of L6E9 myoblasts to form myotubes, without affecting myoblast proliferation, elongation, or alignment. Myogenic events like the induction of myogenin and of glucose carrier GLUT4 were also blocked and myoblasts could not exit the cell cycle, as measured by the lack of mRNA induction of p21 cyclin-dependent kinase inhibitor. Overexpresssion of MyoD in 10T1/2 cells was not sufficient to bypass the myogenic differentiation blockade by LY294002. Upon serum withdrawal, 10T1/2-MyoD cells formed myotubes and showed increased levels of myogenin and p21. In contrast, LY294002-treated cells exhibited none of these myogenic characteristics and maintained high levels of Id, a negative regulator of myogenesis. These data indicate that whereas phosphatidylinositol 3-kinase is not indispensable for cell proliferation or in the initial events of myoblast differentiation, i.e. elongation and alignment, it appears to be essential for terminal differentiation of muscle cells. PMID:8702591

  17. Effect of kinase inhibitors on the therapeutic properties of monoclonal antibodies

    OpenAIRE

    Duong, Minh Ngoc; Matera, Eva-Laure; Mathé, Doriane; Evesque, Anne; Valsesia-Wittmann, Sandrine; Clémenceau, Béatrice; Dumontet, Charles

    2014-01-01

    Targeted therapies of malignancies currently consist of therapeutic monoclonal antibodies and small molecule kinase inhibitors. The combination of these novel agents raises the issue of potential antagonisms. We evaluated the potential effect of 4 kinase inhibitors, including the Bruton tyrosine kinase inhibitor ibrutinib, and 3 PI3K inhibitors idelalisib, NVP-BEZ235 and LY294002, on the effects of the 3 monoclonal antibodies, rituximab and obinutuzumab (directed against CD20) and trastuzumab...

  18. Growth inhibition by tyrosine kinase inhibitors in mesothelioma cell lines.

    Science.gov (United States)

    Nutt, Joyce E; O'Toole, Kieran; Gonzalez, David; Lunec, John

    2009-06-01

    Clinical outcome following chemotherapy for malignant pleural mesothelioma is poor and improvements are needed. This preclinical study investigates the effect of five tyrosine kinase inhibitors (PTK787, ZD6474, ZD1839, SU6668 and SU11248) on the growth of three mesothelioma cell lines (NCI H226, NCI H28 and MSTO 211H), the presence of growth factor receptors and inhibition of their downstream signalling pathways. GI50 values were determined: ZD6474 and SU11248, mainly VEGFR2 inhibitors, gave the lowest GI50 across all cell lines (3.5-6.9 microM) whereas ZD1839 gave a GI50 in this range only in H28 cells. All cell lines were positive for EGFR, but only H226 cells were positive for VEGFR2 by Western blotting. ZD6474 and ZD1839 inhibited EGF-induced phosphorylation of EGFR, AKT and ERK, whereas VEGF-induced phosphorylation of VEGFR2 was completely inhibited with 0.1 microM SU11248. VEGFR2 was detected in tumour samples by immunohistochemistry. VEGFR2 tyrosine kinase inhibitors warrant further investigation in mesothelioma. PMID:19318229

  19. Screening of protein kinase inhibitors identifies PKC inhibitors as inhibitors of osteoclastic acid secretion and bone resorption

    DEFF Research Database (Denmark)

    Sørensen, Mette G; Henriksen, Kim; Sørensen, Mette Guldmann;

    2010-01-01

    Bone resorption is initiated by osteoclastic acidification of the resorption lacunae. This process is mediated by secretion of protons through the V-ATPase and chloride through the chloride antiporter ClC-7. To shed light on the intracellular signalling controlling extracellular acidification, we...... screened a protein kinase inhibitor library in human osteoclasts....

  20. How to awaken your nanomachines: Site-specific activation of focal adhesion kinases through ligand interactions

    KAUST Repository

    Walkiewicz, Katarzyna W.

    2015-06-17

    The focal adhesion kinase (FAK) and the related protein-tyrosine kinase 2-beta (Pyk2) are highly versatile multidomain scaffolds central to cell adhesion, migration, and survival. Due to their key role in cancer metastasis, understanding and inhibiting their functions are important for the development of targeted therapy. Because FAK and Pyk2 are involved in many different cellular functions, designing drugs with partial and function-specific inhibitory effects would be desirable. Here, we summarise recent progress in understanding the structural mechanism of how the tug-of-war between intramolecular and intermolecular interactions allows these protein ‘nanomachines’ to become activated in a site-specific manner.

  1. Focal adhesion kinase regulates expression of thioredoxin-interacting protein (TXNIP) in cancer cells.

    Science.gov (United States)

    Ho, Baotran; Huang, Grace; Golubovskaya, Vita M

    2014-01-01

    Focal Adhesion Kinase (FAK) plays an important role in cancer cell survival. Previous microarray gene profiling study detected inverse regulation between expression of thioredoxin-interacting protein (TXNIP) and FAK, where down-regulation of FAK by siRNA in MCF-7 cells caused up-regulation of TXNIP mRNA level, and in contrast up-regulation of doxycyclin- induced FAK caused repression of TXNIP. In the present report, we show that overexpression of FAK in MCF-7 cells repressed TXNIP promoter activity. Treatment of MCF-7 cells with 1alpha, 25-dihydroxyvitamin D3 (1,25D) down-regulated endogenous FAK and up-regulated TXNIP protein level, and treatment with 5-FU decreased FAK protein expression and up-regulated TXNIP protein expression in 293 cells. Moreover, silencing of FAK with siRNA increased TXNIP protein expression, while overexpression of FAK inhibited TXNIP protein expression in 293 cells. In addition, treatment of DBTRG glioblastoma cells with FAK inhibitor Y15 increased TXNIP mRNA, decreased cancer cell viability and increased apoptosis. These results for the first time demonstrate FAK-regulated TXNIP expression which is important for apoptotic, survival and oxidative stress signaling pathways in cancer cells. PMID:23387972

  2. Copper deficiency induced emphysema is associated with focal adhesion kinase inactivation.

    Directory of Open Access Journals (Sweden)

    Shiro Mizuno

    Full Text Available BACKGROUND: Copper is an important regulator of hypoxia inducible factor 1 alpha (HIF-1α dependent vascular endothelial growth factor (VEGF expression, and is also required for the activity of lysyl oxidase (LOX to effect matrix protein cross-linking. Cell detachment from the extracellular matrix can induce apoptosis (anoikis via inactivation of focal adhesion kinase (FAK. METHODOLOGY: To examine the molecular mechanisms whereby copper depletion causes the destruction of the normal alveolar architecture via anoikis, Male Sprague-Dawley rats were fed a copper deficient diet for 6 weeks while being treated with the copper chelator, tetrathiomolybdate. Other groups of rats were treated with the inhibitor of auto-phosphorylation of FAK, 1,2,4,5-benzenetetraamine tetrahydrochloride (1,2,4,5-BT or FAK small interfering RNA (siRNA. PRINCIPAL FINDINGS: Copper depletion caused emphysematous changes, decreased HIF-1α activity, and downregulated VEGF expression in the rat lungs. Cleaved caspase-3, caspase-8 and Bcl-2 interacting mediator of cell death (Bim expression was increased, and the phosphorylation of FAK was decreased in copper depleted rat lungs. Administration of 1,2,4,5-BT and FAK siRNA caused emphysematous lung destruction associated with increased expression of cleaved capase-3, caspase-8 and Bim. CONCLUSIONS: These data indicate that copper-dependent mechanisms contribute to the pathogenesis of emphysema, which may be associated with decreased HIF-1α and FAK activity in the lung.

  3. Reduced Mechanical Stretch Induces Enhanced Endothelin B Receptor-mediated Contractility via Activation of Focal Adhesion Kinase and Extra Cellular-regulated Kinase 1/2 in Cerebral Arteries from Rat

    DEFF Research Database (Denmark)

    Rasmussen, Marianne N P; Spray, Stine; Skovsted, Gry F;

    2016-01-01

    Cerebral ischaemia results in enhanced endothelin B (ETB ) receptor-mediated contraction and receptor protein expression in the affected cerebrovascular smooth muscle cells (SMC). Organ culture of cerebral arteries is a method to induce similar alterations in ETB receptor expression. We hypothesize...... ETB receptor agonist sarafotoxin 6c. The involvement of extracellular regulated kinase (ERK) 1/2 and focal adhesion kinase (FAK) were studied by their specific inhibitors U0126 and PF-228, respectively. Compared to their stretched counterparts, un-stretched MCA segments showed a significantly...

  4. Combined effects of EGFR tyrosine kinase inhibitors and vATPase inhibitors in NSCLC cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyeon-Ok [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Hong, Sung-Eun [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Kim, Chang Soon [Department of Microbiological Engineering, Kon-Kuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 143–701 (Korea, Republic of); Park, Jin-Ah; Kim, Jin-Hee; Kim, Ji-Young; Kim, Bora [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Chang, Yoon Hwan; Hong, Seok-Il; Hong, Young Jun [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Park, In-Chul, E-mail: parkic@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Lee, Jin Kyung, E-mail: jklee@kirams.re.kr [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of)

    2015-08-15

    Despite excellent initial clinical responses of non-small cell lung cancer (NSCLC) patients to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), many patients eventually develop resistance. According to a recent report, vacuolar H + ATPase (vATPase) is overexpressed and is associated with chemotherapy drug resistance in NSCLC. We investigated the combined effects of EGFR TKIs and vATPase inhibitors and their underlying mechanisms in the regulation of NSCLC cell death. We found that combined treatment with EGFR TKIs (erlotinib, gefitinib, or lapatinib) and vATPase inhibitors (bafilomycin A1 or concanamycin A) enhanced synergistic cell death compared to treatments with each drug alone. Treatment with bafilomycin A1 or concanamycin A led to the induction of Bnip3 expression in an Hif-1α dependent manner. Knock-down of Hif-1α or Bnip3 by siRNA further enhanced cell death induced by bafilomycin A1, suggesting that Hif-1α/Bnip3 induction promoted resistance to cell death induced by the vATPase inhibitors. EGFR TKIs suppressed Hif-1α and Bnip3 expression induced by the vATPase inhibitors, suggesting that they enhanced the sensitivity of the cells to these inhibitors by decreasing Hif-1α/Bnip3 expression. Taken together, we conclude that EGFR TKIs enhance the sensitivity of NSCLC cells to vATPase inhibitors by decreasing Hif-1α/Bnip3 expression. We suggest that combined treatment with EGFR TKIs and vATPase inhibitors is potentially effective for the treatment of NSCLC. - Highlights: • Co-treatment with EGFR TKIs and vATPase inhibitors induces synergistic cell death • EGFR TKIs enhance cell sensitivity to vATPase inhibitors via Hif-1α downregulation • Co-treatment of these inhibitors is potentially effective for the treatment of NSCLC.

  5. Toward the rational design of protein kinase casein kinase-2 inhibitors.

    Science.gov (United States)

    Sarno, Stefania; Moro, Stefano; Meggio, Flavio; Zagotto, Giuseppe; Dal Ben, Diego; Ghisellini, Paola; Battistutta, Roberto; Zanotti, Giuseppe; Pinna, Lorenzo A

    2002-01-01

    Casein kinase-2 (CK2) probably is the most pleiotropic member of the protein kinase family, with more than 200 substrates known to date. Unlike the great majority of protein kinases, which are tightly regulated enzymes, CK2 is endowed with high constitutive activity, a feature that is suspected to underlie its oncogenic potential and possible implication in viral infections. This makes CK2 an attractive target for anti-neoplastic and antiviral drugs. Here, we present an overview of our present knowledge about CK2 inhibitors, with special reference to the information drawn from two recently solved crystal structures of CK2alpha in complex with emodin and with 4,5,6,7-tetrabromo-2-azabenzimidazole (TBB), this latter being the most specific CK2 inhibitor known to date. A comparison with a series of anthraquinone and xanthenone derivatives highlights the crucial relevance of the hydroxyl group at position 3 for inhibition by emodin, and discloses the possibility of increasing the inhibitory potency by placing an electron withdrawing group at position 5. We also present mutational data corroborating the relevance of two hydrophobic residues unique to CK2, Val66 and Ile174, for the interactions with emodin and TBB, but not with the flavonoid inhibitors quercetin and fisetin. In particular, the CK2alpha mutant V66A displays 27- and 11-fold higher IC(50) values with emodin and TBB, respectively, as compared with the wild-type, while the IC(50) value with quercetin is unchanged. The data presented pave the road toward the rational design of more potent and selective inhibitors of CK2 and the generation of CK2 mutants refractory to inhibition, useful to probe the implication of CK2 in specific cellular functions. PMID:12191608

  6. Crystal structure of inhibitor of ;#954;B kinase [beta

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Guozhou; Lo, Yu-Chih; Li, Qiubai; Napolitano, Gennaro; Wu, Xuefeng; Jiang, Xuliang; Dreano, Michel; Karin, Michael; Wu, Hao (Weill-Med); (Merck-Serono); (UCSD); (EMD Serono)

    2011-07-26

    Inhibitor of {kappa}B (I{kappa}B) kinase (IKK) phosphorylates I{kappa}B proteins, leading to their degradation and the liberation of nuclear factor {kappa}B for gene transcription. Here we report the crystal structure of IKK{beta} in complex with an inhibitor, at a resolution of 3.6 {angstrom}. The structure reveals a trimodular architecture comprising the kinase domain, a ubiquitin-like domain (ULD) and an elongated, {alpha}-helical scaffold/dimerization domain (SDD). Unexpectedly, the predicted leucine zipper and helix-loop-helix motifs do not form these structures but are part of the SDD. The ULD and SDD mediate a critical interaction with I{kappa}B{alpha} that restricts substrate specificity, and the ULD is also required for catalytic activity. The SDD mediates IKK{beta} dimerization, but dimerization per se is not important for maintaining IKK{beta} activity and instead is required for IKK{beta} activation. Other IKK family members, IKK{alpha}, TBK1 and IKK-i, may have a similar trimodular architecture and function.

  7. FAK dimerization controls its kinase-dependent functions at focal adhesions

    KAUST Repository

    Brami-Cherrier, Karen

    2014-01-30

    Focal adhesion kinase (FAK) controls adhesion-dependent cell motility, survival, and proliferation. FAK has kinase-dependent and kinase-independent functions, both of which play major roles in embryogenesis and tumor invasiveness. The precise mechanisms of FAK activation are not known. Using x-ray crystallography, small angle x-ray scattering, and biochemical and functional analyses, we show that the key step for activation of FAK\\'s kinase-dependent functions-autophosphorylation of tyrosine-397-requires site-specific dimerization of FAK. The dimers form via the association of the N-terminal FERM domain of FAK and are stabilized by an interaction between FERM and the C-terminal FAT domain. FAT binds to a basic motif on FERM that regulates co-activation and nuclear localization. FAK dimerization requires local enrichment, which occurs specifically at focal adhesions. Paxillin plays a dual role, by recruiting FAK to focal adhesions and by reinforcing the FAT:FERM interaction. Our results provide a structural and mechanistic framework to explain how FAK combines multiple stimuli into a site-specific function. The dimer interfaces we describe are promising targets for blocking FAK activation. © 2014 The Authors.

  8. An evaluation of indirubin analogues as phosphorylase kinase inhibitors.

    Science.gov (United States)

    Begum, Jaida; Skamnaki, Vassiliki T; Moffatt, Colin; Bischler, Nicolas; Sarrou, Josephine; Skaltsounis, Alexios-Leandros; Leonidas, Demetres D; Oikonomakos, Nikos G; Hayes, Joseph M

    2015-09-01

    Phosphorylase kinase (PhK) has been linked with a number of conditions such as glycogen storage diseases, psoriasis, type 2 diabetes and more recently, cancer (Camus et al., 2012 [6]). However, with few reported structural studies on PhK inhibitors, this hinders a structure based drug design approach. In this study, the inhibitory potential of 38 indirubin analogues have been investigated. 11 of these ligands had IC50 values in the range 0.170-0.360μM, with indirubin-3'-acetoxime (1c) the most potent. 7-Bromoindirubin-3'-oxime (13b), an antitumor compound which induces caspase-independent cell-death (Ribas et al., 2006 [20]) is revealed as a specific inhibitor of PhK (IC50=1.8μM). Binding assay experiments performed using both PhK-holo and PhK-γtrnc confirmed the inhibitory effects to arise from binding at the kinase domain (γ subunit). High level computations using QM/MM-PBSA binding free energy calculations were in good agreement with experimental binding data, as determined using statistical analysis, and support binding at the ATP-binding site. The value of a QM description for the binding of halogenated ligands exhibiting σ-hole effects is highlighted. A new statistical metric, the 'sum of the modified logarithm of ranks' (SMLR), has been defined which measures performance of a model for both the "early recognition" (ranking earlier/higher) of active compounds and their relative ordering by potency. Through a detailed structure activity relationship analysis considering other kinases (CDK2, CDK5 and GSK-3α/β), 6'(Z) and 7(L) indirubin substitutions have been identified to achieve selective PhK inhibition. The key PhK binding site residues involved can also be targeted using other ligand scaffolds in future work. PMID:26364215

  9. Receptor Tyrosine Kinase and Tyrosine Kinase Inhibitors: New Hope for Success in Multiple Sclerosis Therapy.

    Science.gov (United States)

    Mirshafiey, Abbas; Ghalamfarsa, Ghasem; Asghari, Babak; Azizi, Gholamreza

    2014-07-01

    Receptor tyrosine kinases (RTKs) are essential components of signal transduction pathways that mediate cell-to-cell communication and their function as relay points for signaling pathways. They have a key role in numerous processes that control cellular proliferation and differentiation, regulate cell growth and cellular metabolism, and promote cell survival and apoptosis. Recently, the role of RTKs including TCR, FLT-3, c-Kit, c-Fms, PDGFR, ephrin, neurotrophin receptor, and TAM receptor in autoimmune disorder, especially rheumatoid arthritis and multiple sclerosis has been suggested. In multiple sclerosis pathogenesis, RTKs and their tyrosine kinase enzymes are selective important targets for tyrosine kinase inhibitor (TKI) agents. TKIs, compete with the ATP binding site of the catalytic domain of several tyrosine kinases, and act as small molecules that have a favorable safety profile in disease treatment. Up to now, the efficacy of TKIs in numerous animal models of MS has been demonstrated, but application of these drugs in human diseases should be tested in future clinical trials.

  10. Structure-based library approach to kinase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Norman, T.C.; Gray, N.S.; Koh, J.T.; Schultz, P.G. [Univ. of California, Berkeley, CA (United States)

    1996-08-07

    While purine analogs were being screened for inhibition of various protein kinases, a relatively selective inhibitor, olomoucine, was identified that competitively inhibits CDK2/cyclin A with an IC{sub 50} of 7 {mu}M. A comparison of the CDK2 crystal structures containing bound ATP and bound olomoucine confirms that olomoucine binds in the adenine binding pocket of CDK2, but its purine nucleus adopts an entirely different orientation than that observed for ATP. In spite of the good shape complementarity shown by the olomoucine-CDK2 complex, structural variations at C-6, C-2, and N-9 might be expected to lead to enhanced affinity and selectivity for CDK2. The coupling of this structural information with combinatorial methods is an obvious strategy for optimizing olomoucine`s potency. Herein we apply this approach to the solid-phase synthesis and screening of combinatorial libraries based on the purine scaffold found in olomoucine. The iteration of library synthesis with structural analysis of the optimized leads should provide an effective strategy for the development of more potent and selective inhibitors of CDK2. In addition, libraries containing purine derivatives may prove useful in the search for inhibitors of a large number of cellular processes. 24 refs., 1 fig.

  11. Study of green film-forming corrosion inhibitor based on mussel adhesive protein

    OpenAIRE

    Holmér, Camilla

    2013-01-01

    Today there are numerous methods to slow down a corrosion process of metallic materials. However, due to environmental effects and health risk issues, several traditional corrosion inhibitors have to be phased out. Hence, it is of great importance to develop new corrosion inhibitors that are “green”, safe, smart and multifunctional. In this essay, the focus is on mussel adhesive protein (MAP) and its possibility to reduce the rate of the corrosion process. The protein exhibit great adhesive s...

  12. The Src homology 2 protein Shb promotes cell cycle progression in murine hematopoietic stem cells by regulation of focal adhesion kinase activity

    International Nuclear Information System (INIS)

    The widely expressed adaptor protein Shb has previously been reported to contribute to T cell function due to its association with the T cell receptor and furthermore, several of Shb's known interaction partners are established regulators of blood cell development and function. In addition, Shb deficient embryonic stem cells displayed reduced blood cell colony formation upon differentiation in vitro. The aim of the current study was therefore to explore hematopoietic stem and progenitor cell function in the Shb knockout mouse. Shb deficient bone marrow contained reduced relative numbers of long-term hematopoietic stem cells (LT-HSCs) that exhibited lower proliferation rates. Despite this, Shb knockout LT-HSCs responded promptly by entering the cell cycle in response to genotoxic stress by 5-fluorouracil treatment. In competitive LT-HSC transplantations, Shb null cells initially engrafted as well as the wild-type cells but provided less myeloid expansion over time. Moreover, Shb knockout bone marrow cells exhibited elevated basal activities of focal adhesion kinase/Rac1/p21-activated kinase signaling and reduced responsiveness to Stem Cell Factor stimulation. Consequently, treatment with a focal adhesion kinase inhibitor increased Shb knockout LT-HSC proliferation. The altered signaling characteristics thus provide a plausible mechanistic explanation for the changes in LT-HSC proliferation since these signaling intermediates have all been shown to participate in LT-HSC cell cycle control. In summary, the loss of Shb dependent signaling in bone marrow cells, resulting in elevated focal adhesion kinase activity and reduced proliferative responses in LT-HSCs under steady state hematopoiesis, confers a disadvantage to the maintenance of LT-HSCs over time. -- Highlights: • Shb is an adaptor protein operating downstream of tyrosine kinase receptors. • Shb deficiency reduces hematopoietic stem cell proliferation. • The proliferative effect of Shb occurs via increased

  13. The Src homology 2 protein Shb promotes cell cycle progression in murine hematopoietic stem cells by regulation of focal adhesion kinase activity

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, Karin [Department of Medical Cell Biology, Uppsala University, Uppsala 751 23 (Sweden); Heffner, Garrett; Wenzel, Pamela L.; Curran, Matthew [HHMI, Children' s Hospital Boston, Harvard Medical School, Boston, 02115 MA (United States); Grawé, Jan [Department of Genetics and Pathology, Uppsala University, Uppsala 75185 (Sweden); McKinney-Freeman, Shannon L. [Department of Hematology, St. Jude Children' s Research Hospital, Memphis, TN 38105 (United States); Daley, George Q. [HHMI, Children' s Hospital Boston, Harvard Medical School, Boston, 02115 MA (United States); Welsh, Michael, E-mail: michael.welsh@mcb.uu.se [Department of Medical Cell Biology, Uppsala University, Uppsala 751 23 (Sweden)

    2013-07-15

    The widely expressed adaptor protein Shb has previously been reported to contribute to T cell function due to its association with the T cell receptor and furthermore, several of Shb's known interaction partners are established regulators of blood cell development and function. In addition, Shb deficient embryonic stem cells displayed reduced blood cell colony formation upon differentiation in vitro. The aim of the current study was therefore to explore hematopoietic stem and progenitor cell function in the Shb knockout mouse. Shb deficient bone marrow contained reduced relative numbers of long-term hematopoietic stem cells (LT-HSCs) that exhibited lower proliferation rates. Despite this, Shb knockout LT-HSCs responded promptly by entering the cell cycle in response to genotoxic stress by 5-fluorouracil treatment. In competitive LT-HSC transplantations, Shb null cells initially engrafted as well as the wild-type cells but provided less myeloid expansion over time. Moreover, Shb knockout bone marrow cells exhibited elevated basal activities of focal adhesion kinase/Rac1/p21-activated kinase signaling and reduced responsiveness to Stem Cell Factor stimulation. Consequently, treatment with a focal adhesion kinase inhibitor increased Shb knockout LT-HSC proliferation. The altered signaling characteristics thus provide a plausible mechanistic explanation for the changes in LT-HSC proliferation since these signaling intermediates have all been shown to participate in LT-HSC cell cycle control. In summary, the loss of Shb dependent signaling in bone marrow cells, resulting in elevated focal adhesion kinase activity and reduced proliferative responses in LT-HSCs under steady state hematopoiesis, confers a disadvantage to the maintenance of LT-HSCs over time. -- Highlights: • Shb is an adaptor protein operating downstream of tyrosine kinase receptors. • Shb deficiency reduces hematopoietic stem cell proliferation. • The proliferative effect of Shb occurs via

  14. Inhibitor-bound structures of human pyruvate dehydrogenase kinase 4.

    Science.gov (United States)

    Kukimoto-Niino, Mutsuko; Tokmakov, Alexander; Terada, Takaho; Ohbayashi, Naomi; Fujimoto, Takako; Gomi, Sumiko; Shiromizu, Ikuya; Kawamoto, Masaki; Matsusue, Tomokazu; Shirouzu, Mikako; Yokoyama, Shigeyuki

    2011-09-01

    The mitochondrial pyruvate dehydrogenase complex (PDC) catalyzes the oxidative decarboxylation of pyruvate to acetyl-CoA. PDC activity is tightly regulated by four members of a family of pyruvate dehydrogenase kinase isoforms (PDK1-4), which phosphorylate and inactivate PDC. Recently, the development of specific inhibitors of PDK4 has become an especially important focus for the pharmaceutical management of diabetes and obesity. In this study, crystal structures of human PDK4 complexed with either AMPPNP, ADP or the inhibitor M77976 were determined. ADP-bound PDK4 has a slightly wider active-site cleft and a more disordered ATP lid compared with AMPPNP-bound PDK4, although both forms of PDK4 assume open conformations with a wider active-site cleft than that in the closed conformation of the previously reported ADP-bound PDK2 structure. M77976 binds to the ATP-binding pocket of PDK4 and causes local conformational changes with complete disordering of the ATP lid. M77976 binding also leads to a large domain rearrangement that further expands the active-site cleft of PDK4 compared with the ADP- and AMPPNP-bound forms. Biochemical analyses revealed that M77976 inhibits PDK4 with increased potency compared with the previously characterized PDK inhibitor radicicol. Thus, the present structures demonstrate for the first time the flexible and dynamic aspects of PDK4 in the open conformation and provide a basis for the development of novel inhibitors targeting the nucleotide-binding pocket of PDK4. PMID:21904029

  15. Exploiting Chemical Libraries, Structure, and Genomics in the Search for Kinase Inhibitors

    NARCIS (Netherlands)

    Gray, Nathanael S.; Wodicka, Lisa; Thunnissen, Andy-Mark W.H.; Norman, Thea C.; Kwon, Soojin; Espinoza, F. Hernan; Morgan, David O.; Barnes, Georjana; LeClerc, Sophie; Meijer, Laurent; Kim, Sung-Hou; Lockhart, David J.; Schultz, Peter G.

    1998-01-01

    Selective protein kinase inhibitors were developed on the basis of the unexpected binding mode of 2,6,9-trisubstituted purines to the adenosine triphosphate-binding site of the human cyclin-dependent kinase 2 (CDK2). By iterating chemical library synthesis and biological screening, potent inhibitors

  16. Template-Based de Novo Design for Type II Kinase Inhibitors and Its Extended Application to Acetylcholinesterase Inhibitors

    OpenAIRE

    Bo-Han Su; Yi-Syuan Huang; Chia-Yun Chang; Yi-Shu Tu; Yufeng J Tseng

    2013-01-01

    There is a compelling need to discover type II inhibitors targeting the unique DFG-out inactive kinase conformation since they are likely to possess greater potency and selectivity relative to traditional type I inhibitors. Using a known inhibitor, such as a currently available and approved drug or inhibitor, as a template to design new drugs via computational de novo design is helpful when working with known ligand-receptor interactions. This study proposes a new template-based de novo desig...

  17. Tyrosine kinase inhibitors induced immune thrombocytopenia in chronic myeloid leukemia?

    Directory of Open Access Journals (Sweden)

    Avital F. Barak

    2011-12-01

    Full Text Available The outcome and quality of life of chronic myeloid leukemia (CML patients has remarkably changed with the treatment of tyrosine kinase inhibitors (TKIs. Currently, hematopoietic stem cell transplantation (HSCT is considered mainly as a third line salvage therapy in cases of TKIs resistance or intolerance. Here we describe a patient with chronic phase CML who developed both resistance and late occurrence of s severe thrombocytopenia on first and second generation TKIs and eventually underwent HSCT. Although the mechanism of the myelosuppression is not fully understood, we showed for the first time the development of dose dependent platelet antibodies in the presence of TKIs, suggesting the possibility of TKIs induced thrombocytopenia. Our case emphasizes that late development of severe myelosuppression during imatinib treatment is probably an important indication for consideration of early HSCT.

  18. Evaluation of tyrosine kinase inhibitor combinations for glioblastoma therapy.

    Directory of Open Access Journals (Sweden)

    Avadhut D Joshi

    Full Text Available Glioblastoma multiforme (GBM is the most common intracranial cancer but despite recent advances in therapy the overall survival remains about 20 months. Whole genome exon sequencing studies implicate mutations in the receptor tyrosine kinase pathways (RTK for driving tumor growth in over 80% of GBMs. In spite of various RTKs being mutated or altered in the majority of GBMs, clinical studies have not been able to demonstrate efficacy of molecular targeted therapies using tyrosine kinase inhibitors in GBMs. Activation of multiple downstream signaling pathways has been implicated as a possible means by which inhibition of a single RTK has been ineffective in GBM. In this study, we sought a combination of approved drugs that would inhibit in vitro and in vivo growth of GBM oncospheres. A combination consisting of gefitinib and sunitinib acted synergistically in inhibiting growth of GBM oncospheres in vitro. Sunitinib was the only RTK inhibitor that could induce apoptosis in GBM cells. However, the in vivo efficacy testing of the gefitinib and sunitinib combination in an EGFR amplified/PTEN wild type GBM xenograft model revealed that gefitinib alone could significantly improve survival in animals whereas sunitinib did not show any survival benefit. Subsequent testing of the same drug combination in a different syngeneic glioma model that lacked EGFR amplification but was more susceptible to sunitinib in vitro demonstrated no survival benefit when treated with gefitinib or sunitinib or the gefitinib and sunitinib combination. Although a modest survival benefit was obtained in one of two animal models with EGFR amplification due to gefitinib alone, the addition of sunitinib, to test our best in vitro combination therapy, did not translate to any additional in vivo benefit. Improved targeted therapies, with drug properties favorable to intracranial tumors, are likely required to form effective drug combinations for GBM.

  19. Targeting Protein Kinase C Downstream of Growth Factor and Adhesion Signalling

    Energy Technology Data Exchange (ETDEWEB)

    Dowling, Catríona M., E-mail: Catriona.Dowling@ul.ie; Kiely, Patrick A., E-mail: Catriona.Dowling@ul.ie [Department of Life Sciences, Materials and Surface Science Institute and Stokes Institute, University of Limerick, Limerick 78666 (Ireland); Health Research Institute (HRI), University of Limerick, Limerick 78666 (Ireland)

    2015-07-15

    The signaling outputs of Receptor Tyrosine Kinases, G-protein coupled receptors and integrins converge to mediate key cell process such as cell adhesion, cell migration, cell invasion and cell proliferation. Once activated by their ligands, these cell surface proteins recruit and direct a diverse range of proteins to disseminate the appropriate response downstream of the specific environmental cues. One of the key groups of proteins required to regulate these activities is the family of serine/threonine intracellular kinases called Protein Kinase Cs. The activity and subcellular location of PKCs are mediated by a series of tightly regulated events and is dependent on several posttranslational modifications and the availability of second messengers. Protein Kinase Cs exhibit both pro- and anti-tumorigenic effects making them an interesting target for anti-cancer treatment.

  20. Novel Phosphotidylinositol 4,5-Bisphosphate Binding Sites on Focal Adhesion Kinase.

    Directory of Open Access Journals (Sweden)

    Jun Feng

    Full Text Available Focal adhesion kinase (FAK is a protein tyrosine kinase that is ubiquitously expressed, recruited to focal adhesions, and engages in a variety of cellular signaling pathways. Diverse cellular responses, such as cell migration, proliferation, and survival, are regulated by FAK. Prior to activation, FAK adopts an autoinhibited conformation in which the FERM domain binds the kinase domain, blocking access to the activation loop and substrate binding site. Activation of FAK occurs through conformational change, and acidic phospholipids such as phosphatidylinositol 4,5-bisphosphate (PIP2 are known to facilitate this process. PIP2 binding alters the autoinhibited conformation of the FERM and kinase domains and subsequently exposes the activation loop to phosphorylation. However, the detailed molecular mechanism of PIP2 binding and its role in FAK activation remain unclear. In this study, we conducted coarse-grained molecular dynamics simulations to investigate the binding of FAK to PIP2. Our simulations identified novel areas of basic residues in the kinase domain of FAK that potentially undergo transient binding to PIP2 through electrostatic attractions. Our investigation provides a molecular picture of PIP2-initiated FAK activation and introduces promising new pathways for future studies of FAK regulation.

  1. Widespread potential for growth-factor-driven resistance to anticancer kinase inhibitors

    OpenAIRE

    Wilson, Timothy R.; Fridlyand, Jane; Yan, Yibing; Penuel, Elicia; Burton, Luciana; Chan, Emily; Peng, Jing; Lin, Eva; Wang, Yulei; Sosman, Jeff; Ribas, Antoni; Li, Jiang; Moffat, John; Sutherlin, Daniel P.; Koeppen, Hartmut

    2012-01-01

    Mutationally activated kinases define a clinically validated class of targets for cancer drug therapy1. However, the efficacy of kinase inhibitors in patients whose tumours harbour such alleles is invariably limited by innate or acquired drug resistance2,3. The identification of resistance mechanisms has revealed a recurrent theme—the engagement of survival signals redundant to those transduced by the targeted kinase4. Cancer cells typically express multiple receptor tyrosine kinases (RTKs) t...

  2. Structure-based lead discovery for protein kinase C zeta inhibitor design by exploiting kinase-inhibitor complex crystal structure data and potential therapeutics for preterm labour.

    Science.gov (United States)

    Shao, Qing-Chun; Zhang, Cui-Juan; Li, Jie

    2014-10-14

    The protein kinase C (PKC) is a family of serine/threonine kinases with a broad range of cellular targets. Members of the PKC family participate at the diverse biological events involved in cellular proliferation, differentiation and survival. The PKC isoform zeta (PKCζ) is an atypical member that has recently been found to play an essential role in promoting human uterine contractility and thus been raised as a new target for treating preterm labour and other tocolytic diseases. In this study, an integrative protocol was described to graft hundreds of inhibitor ligands from their complex crystal structures with cognate kinases into the active pocket of PKCζ and, based on the modeled structures, to evaluate the binding strength of these inhibitors to the non-cognate PKCζ receptor by using a consensus scoring strategy. A total of 32 inhibitors with top score were compiled, and eight out of them were tested for inhibitory potency against PKCζ. Consequently, five compounds, i.e. CDK6 inhibitor fisetin, PIM1 inhibitor myricetin, CDK9 inhibitor flavopiridol and PknB inhibitor mitoxantrone as well as the promiscuous kinase inhibitor staurosporine showed high or moderate inhibitory activity on PKCζ, with IC50 values of 58 ± 9, 1.7 ± 0.4, 108 ± 17, 280 ± 47 and 0.019 ± 0.004 μM, respectively, while other three compounds, including two marketed drugs dasatinib and sunitinib as well as the Rho inhibitor fasudil, have not been detected to possess observable activity. Next, based on the modeled structure data we modified three flavonoid kinase inhibitors, i.e. fisetin, myricetin and flavopiridol, to generate a number of more potential molecular entities, two of which were found to have a moderately improved activity as compared to their parent compounds.

  3. Activation of AMP-activated protein kinase attenuates hepatocellular carcinoma cell adhesion stimulated by adipokine resistin

    International Nuclear Information System (INIS)

    Resistin, adipocyte-secreting adipokine, may play critical role in modulating cancer pathogenesis. The aim of this study was to investigate the effects of resistin on HCC adhesion to the endothelium, and the mechanism underlying these resistin effects. Human SK-Hep1 cells were used to study the effect of resistin on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions as well as NF-κB activation, and hence cell adhesion to human umbilical vein endothelial cells (HUVECs). 5-Aminoimidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR), an AMP-activated protein kinase (AMPK) activator, was used to determine the regulatory role of AMPK on HCC adhesion to the endothelium in regard to the resistin effects. Treatment with resistin increased the adhesion of SK-Hep1 cells to HUVECs and concomitantly induced NF-κB activation, as well as ICAM-1 and VCAM-1 expressions in SK-Hep1 cells. Using specific blocking antibodies and siRNAs, we found that resistin-induced SK-Hep1 cell adhesion to HUVECs was through NF-κB-regulated ICAM-1 and VCAM-1 expressions. Moreover, treatment with AICAR demonstrated that AMPK activation in SK-Hep1 cells significantly attenuates the resistin effect on SK-Hep1 cell adhesion to HUVECs. These results clarify the role of resistin in inducing HCC adhesion to the endothelium and demonstrate the inhibitory effect of AMPK activation under the resistin stimulation. Our findings provide a notion that resistin play an important role to promote HCC metastasis and implicate AMPK may be a therapeutic target to against HCC metastasis

  4. Doxycycline inhibits leukemic cell migration via inhibition of matrix metalloproteinases and phosphorylation of focal adhesion kinase

    OpenAIRE

    WANG, CHUNHUAI; Xiang, Ru; ZHANG, XIANGZHONG; CHEN, YUNXIAN

    2015-01-01

    Doxycycline, a tetracycline-based antibiotic, has been reported to attenuate melanoma cell migration through inhibiting the focal adhesion kinase (FAK) signaling pathway. However, it remains to be elucidated whether doxycycline exerts this effect on leukemia cell migration. The present study aimed to examine the role of doxycycline in leukemia cell migration. The invasion capacities of the human leukemia cell lines KG1a (acute myelogenous leukemia) and K562 (chronic myelogenous leukemia) were...

  5. Benzothiophene inhibitors of MK2. Part 2: improvements in kinase selectivity and cell potency.

    Science.gov (United States)

    Anderson, David R; Meyers, Marvin J; Kurumbail, Ravi G; Caspers, Nicole; Poda, Gennadiy I; Long, Scott A; Pierce, Betsy S; Mahoney, Matthew W; Mourey, Robert J; Parikh, Mihir D

    2009-08-15

    Optimization of kinase selectivity for a set of benzothiophene MK2 inhibitors provided analogs with potencies of less than 500 nM in a cell based assay. The selectivity of the inhibitors can be rationalized by examination of X-ray crystal structures of inhibitors bound to MK2.

  6. Benzothiophene inhibitors of MK2. Part 2: Improvements in kinase selectivity and cell potency

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, David R.; Meyers, Marvin J.; Kurumbail, Ravi G.; Caspers, Nicole; Poda, Gennadiy I.; Long, Scott A.; Pierce, Betsy S.; Mahoney, Matthew W.; Mourey, Robert J.; Parikh, Mihir D.; Pfizer

    2010-10-01

    Optimization of kinase selectivity for a set of benzothiophene MK2 inhibitors provided analogs with potencies of less than 500 nM in a cell based assay. The selectivity of the inhibitors can be rationalized by examination of X-ray crystal structures of inhibitors bound to MK2.

  7. Combined HSP90 and kinase inhibitor therapy: Insights from The Cancer Genome Atlas.

    Science.gov (United States)

    Schwartz, Harvey; Scroggins, Brad; Zuehlke, Abbey; Kijima, Toshiki; Beebe, Kristin; Mishra, Alok; Neckers, Len; Prince, Thomas

    2015-09-01

    The merging of knowledge from genomics, cellular signal transduction and molecular evolution is producing new paradigms of cancer analysis. Protein kinases have long been understood to initiate and promote malignant cell growth and targeting kinases to fight cancer has been a major strategy within the pharmaceutical industry for over two decades. Despite the initial success of kinase inhibitors (KIs), the ability of cancer to evolve resistance and reprogram oncogenic signaling networks has reduced the efficacy of kinase targeting. The molecular chaperone HSP90 physically supports global kinase function while also acting as an evolutionary capacitor. The Cancer Genome Atlas (TCGA) has compiled a trove of data indicating that a large percentage of tumors overexpress or possess mutant kinases that depend on the HSP90 molecular chaperone complex. Moreover, the overexpression or mutation of parallel activators of kinase activity (PAKA) increases the number of components that promote malignancy and indirectly associate with HSP90. Therefore, targeting HSP90 is predicted to complement kinase inhibitors by inhibiting oncogenic reprogramming and cancer evolution. Based on this hypothesis, consideration should be given by both the research and clinical communities towards combining kinase inhibitors and HSP90 inhibitors (H90Ins) in combating cancer. The purpose of this perspective is to reflect on the current understanding of HSP90 and kinase biology as well as promote the exploration of potential synergistic molecular therapy combinations through the utilization of The Cancer Genome Atlas. PMID:26070366

  8. Fluid-flow-induced mesenchymal stem cell migration: role of focal adhesion kinase and RhoA kinase sensors.

    Science.gov (United States)

    Riehl, Brandon D; Lee, Jeong Soon; Ha, Ligyeom; Lim, Jung Yul

    2015-03-01

    The study of mesenchymal stem cell (MSC) migration under flow conditions with investigation of the underlying molecular mechanism could lead to a better understanding and outcome in stem-cell-based cell therapy and regenerative medicine. We used peer-reviewed open source software to develop methods for efficiently and accurately tracking, measuring and processing cell migration as well as morphology. Using these tools, we investigated MSC migration under flow-induced shear and tested the molecular mechanism with stable knockdown of focal adhesion kinase (FAK) and RhoA kinase (ROCK). Under steady flow, MSCs migrated following the flow direction in a shear stress magnitude-dependent manner, as assessed by root mean square displacement and mean square displacement, motility coefficient and confinement ratio. Silencing FAK in MSCs suppressed morphology adaptation capability and reduced cellular motility for both static and flow conditions. Interestingly, ROCK silencing significantly increased migration tendency especially under flow. Blocking ROCK, which is known to reduce cytoskeletal tension, may lower the resistance to skeletal remodelling during the flow-induced migration. Our data thus propose a potentially differential role of focal adhesion and cytoskeletal tension signalling elements in MSC migration under flow shear.

  9. Afatinib: emerging next-generation tyrosine kinase inhibitor for NSCLC

    Directory of Open Access Journals (Sweden)

    Nelson V

    2013-03-01

    Full Text Available Valerie Nelson, Jacqueline Ziehr, Mark Agulnik, Melissa JohnsonRobert H Lurie Comprehensive Cancer Center of Northwestern University, Chicago, IL, USAAbstract: The discovery of epidermal growth-factor receptor (EGFR-activating mutations and the introduction of oral EGFR tyrosine kinase inhibitors (EGFR-TKIs have expanded the treatment options for patients with non-small cell lung cancer. The first two reversible EGFR-TKIs, erlotinib and gefitinib, are approved for use in the first-line setting in patients with known EGFR-activating mutations and in the second- and third-line settings for all NSCLC patients. These first-generation EGFR-TKIs improve progression-free survival when compared to chemotherapy in patients with EGFR-activating mutations in the first-line setting. However, nearly all patients develop resistance to EGFR-directed agents. There is a need for further therapy options for patients with disease progression after treatment with reversible EGFR-TKIs. Afatinib is an irreversible ErbB family blocker that inhibits EGFR, HER2, and HER4. In vitro and in vivo, afatinib have shown increased inhibition of the common EGFR-activating mutations as well as the T790M resistance mutation when compared to erlotinib and gefitinib. Clinically, afatinib has been evaluated in the LUX-Lung series of trials, with improvement in progression-free survival reported in patients with EGFR-activating mutations in both first- and second-/third-line settings when compared to chemotherapy. Further investigation is needed to determine the precise role that afatinib will play in the treatment of patients with non-small cell lung cancer and EGFR-activating mutations.Keywords: afatinib, EGFR, irreversible EGFR inhibitor, EGPR-TKIs, LUX lung, resistance mutation, targeted therapy

  10. Matriptase is required for the active form of hepatocyte growth factor induced Met, focal adhesion kinase and protein kinase B activation on neural stem/progenitor cell motility.

    Science.gov (United States)

    Fang, Jung-Da; Lee, Sheau-Ling

    2014-07-01

    Hepatocyte growth factor (HGF) is a chemoattractant and inducer for neural stem/progenitor (NS/P) cell migration. Although the type II transmembrane serine protease, matriptase (MTP) is an activator of the latent HGF, MTP is indispensable on NS/P cell motility induced by the active form of HGF. This suggests that MTP's action on NS/P cell motility involves mechanisms other than proteolytic activation of HGF. In the present study, we investigate the role of MTP in HGF-stimulated signaling events. Using specific inhibitors of phosphatidylinositol-3-kinase (PI3K), protein kinase B (Akt) or focal adhesion kinase (FAK), we demonstrated that in NS/P cells HGF-activated c-Met induces PI3k-Akt signaling which then leads to FAK activation. This signaling pathway ultimately induces MMP2 expression and NS/P cell motility. Knocking down of MTP in NS/P cells with specific siRNA impaired HGF-stimulation of c-Met, Akt and FAK activation, blocked HGF-induced production of MMP2 and inhibited HGF-stimulated NS/P cell motility. MTP-knockdown NS/P cells cultured in the presence of recombinant protein of MTP protease domain or transfected with the full-length wild-type but not the protease-defected MTP restored HGF-responsive events in NS/P cells. In addition to functioning as HGF activator, our data revealed novel function of MTP on HGF-stimulated c-Met signaling activation.

  11. Structure of Human G Protein-Coupled Receptor Kinase 2 in Complex with the Kinase Inhibitor Balanol

    Energy Technology Data Exchange (ETDEWEB)

    Tesmer, John J.G.; Tesmer, Valerie M.; Lodowski, David T.; Steinhagen, Henning; Huber, Jochen (Sanofi); (Michigan); (Texas)

    2010-07-19

    G protein-coupled receptor kinase 2 (GRK2) is a pharmaceutical target for the treatment of cardiovascular diseases such as congestive heart failure, myocardial infarction, and hypertension. To better understand how nanomolar inhibition and selectivity for GRK2 might be achieved, we have determined crystal structures of human GRK2 in complex with G{beta}{gamma} in the presence and absence of the AGC kinase inhibitor balanol. The selectivity of balanol among human GRKs is assessed.

  12. Checkpoint kinase inhibitors: SAR and radioprotective properties of a series of 2-arylbenzimidazoles.

    Science.gov (United States)

    Arienti, Kristen L; Brunmark, Anders; Axe, Frank U; McClure, Kelly; Lee, Alice; Blevitt, Jon; Neff, Danielle K; Huang, Liming; Crawford, Shelby; Pandit, Chennagiri R; Karlsson, Lars; Breitenbucher, J Guy

    2005-03-24

    The discovery of a series of novel, potent, and highly selective inhibitors of the DNA damage control kinase chk2 is disclosed. Here we report the first SAR study around inhibitors of this kinase. High-throughput screening of purified human chk2 led to the identification of a novel series of 2-arylbenzimidazole inhibitors of the kinase. Optimization was facilitated using homology models of chk2 and docking of inhibitors, leading to the highly potent 2-arylbenzimidazole 2h (IC(50) 15 nM). Compound 2h is an ATP-competitive inhibitor of chk2 that dose dependently protects human CD4(+) and CD8(+) T-cells from apoptosis due to ionizing radiation. This work suggests that a selective small molecule inhibitor of chk2 could be a useful adjuvant to radiotherapy, increasing the therapeutic window of such treatment. PMID:15771432

  13. Identification of inhibitors of checkpoint kinase 1 through template screening.

    Science.gov (United States)

    Matthews, Thomas P; Klair, Suki; Burns, Samantha; Boxall, Kathy; Cherry, Michael; Fisher, Martin; Westwood, Isaac M; Walton, Michael I; McHardy, Tatiana; Cheung, Kwai-Ming J; Van Montfort, Rob; Williams, David; Aherne, G Wynne; Garrett, Michelle D; Reader, John; Collins, Ian

    2009-08-13

    Checkpoint kinase 1 (CHK1) is an oncology target of significant current interest. Inhibition of CHK1 abrogates DNA damage-induced cell cycle checkpoints and sensitizes p53 deficient cancer cells to genotoxic therapies. Using template screening, a fragment-based approach to small molecule hit generation, we have identified multiple CHK1 inhibitor scaffolds suitable for further optimization. The sequential combination of in silico low molecular weight template selection, a high concentration biochemical assay and hit validation through protein-ligand X-ray crystallography provided 13 template hits from an initial in silico screening library of ca. 15000 compounds. The use of appropriate counter-screening to rule out nonspecific aggregation by test compounds was essential for optimum performance of the high concentration bioassay. One low molecular weight, weakly active purine template hit was progressed by iterative structure-based design to give submicromolar pyrazolopyridines with good ligand efficiency and appropriate CHK1-mediated cellular activity in HT29 colon cancer cells. PMID:19572549

  14. Interleukin-2 induces beta2-integrin-dependent signal transduction involving the focal adhesion kinase-related protein B (fakB)

    DEFF Research Database (Denmark)

    Brockdorff, J; Kanner, S B; Nielsen, M;

    1998-01-01

    experiments indicate that the IL-2-induced 125-kDa phosphotyrosine protein is the focal adhesion kinase-related protein B (fakB). Thus, IL-2 induces strong tyrosine phosphorylation of fakB in beta2-integrin-positive but not in beta2-integrin-negative T cells, and CD18 mAb selectively blocks IL-2-induced fakB......-tyrosine phosphorylation in beta2-integrin-positive T cells. In parallel experiments, IL-2 does not induce or augment tyrosine phosphorylation of p125(FAK). In conclusion, our data indicate that IL-2 induces beta2-integrin-dependent signal transduction events involving the tyrosine kinase substrate fakB....... and a leukocyte adhesion deficiency (LAD) patient. We show that IL-2 induces tyrosine phosphorylation of a 125-kDa protein and homotypic adhesion in beta2 integrin (CD18)-positive but not in beta2-integrin-negative T cells. EDTA, an inhibitor of integrin adhesion, blocks IL-2-induced tyrosine phosphorylation...

  15. Inhibitors of 5-lipoxygenase inhibit expression of intercellular adhesion molecule-1 in human melanoma cells

    Institute of Scientific and Technical Information of China (English)

    Yin WANG; Bin ZHOU; Ji LI; Yong-bing CAO; Xin-sheng CHEN; Ming-he CHENG; Ming YIN

    2004-01-01

    AIM: To study the effect of 5-lipoxygenase inhibitors on the expression of intercellular adhesion molecule-1 (ICAM-1) in melanoma cells. METHODS: ICAM-1 protein of human melanoma cell a375 was detected by enzyme-linked immunosorbent, flow cytometry and Western blot analysis. Level of ICAM-1 mRNA in a375 was evaluated by Northern blot analysis. Adhesion of a375 to endothelial cell EC304 was analyzed by isotopic tracing. RESULTS:5-Lipoxygenase inhibitors nordihydroguaiaretic acid, AA861 and MK886, could suppress the expression of ICAM-1 protein as well as of its mRNA in a375 cells and reduce the adhesion of a375 to EC304. CONCLUSION:5-Lipoxygenase inhibitors can inhibit the expression of ICAM-1 in human melanoma cells and may be valuable for treatment of melanoma metastasis.

  16. Conformational Dynamics of the Focal Adhesion Targeting Domain Control Specific Functions of Focal Adhesion Kinase in Cells

    KAUST Repository

    Kadaré, Gress

    2015-01-02

    Focal adhesion (FA) kinase (FAK) regulates cell survival and motility by transducing signals from membrane receptors. The C-terminal FA targeting (FAT) domain of FAK fulfils multiple functions, including recruitment to FAs through paxillin binding. Phosphorylation of FAT on Tyr925 facilitates FA disassembly and connects to the MAPK pathway through Grb2 association, but requires dissociation of the first helix (H1) of the four-helix bundle of FAT. We investigated the importance of H1 opening in cells by comparing the properties of FAK molecules containing wild-type or mutated FAT with impaired or facilitated H1 openings. These mutations did not alter the activation of FAK, but selectively affected its cellular functions, including self-association, Tyr925 phosphorylation, paxillin binding, and FA targeting and turnover. Phosphorylation of Tyr861, located between the kinase and FAT domains, was also enhanced by the mutation that opened the FAT bundle. Similarly phosphorylation of Ser910 by ERK in response to bombesin was increased by FAT opening. Although FAK molecules with the mutation favoring FAT opening were poorly recruited at FAs, they efficiently restored FA turnover and cell shape in FAK-deficient cells. In contrast, the mutation preventing H1 opening markedly impaired FAK function. Our data support the biological importance of conformational dynamics of the FAT domain and its functional interactions with other parts of the molecule.

  17. Quinalizarin as a potent, selective and cell-permeable inhibitor of protein kinase CK2.

    Science.gov (United States)

    Cozza, Giorgio; Mazzorana, Marco; Papinutto, Elena; Bain, Jenny; Elliott, Matthew; di Maira, Giovanni; Gianoncelli, Alessandra; Pagano, Mario A; Sarno, Stefania; Ruzzene, Maria; Battistutta, Roberto; Meggio, Flavio; Moro, Stefano; Zagotto, Giuseppe; Pinna, Lorenzo A

    2009-08-01

    Emodin (1,3,8-trihydroxy-6-methyl-anthraquinone) is a moderately potent and poorly selective inhibitor of protein kinase CK2, one of the most pleiotropic serine/threonine protein kinases, implicated in neoplasia and in other global diseases. By virtual screening of the MMS (Molecular Modeling Section) database, we have now identified quinalizarin (1,2,5,8-tetrahydroxyanthraquinone) as an inhibitor of CK2 that is more potent and selective than emodin. CK2 inhibition by quinalizarin is competitive with respect to ATP, with a Ki value of approx. 50 nM. Tested at 1 microM concentration on a panel of 75 protein kinases, quinalizarin drastically inhibits only CK2, with a promiscuity score (11.1), which is the lowest ever reported so far for a CK2 inhibitor. Especially remarkable is the ability of quinalizarin to discriminate between CK2 and a number of kinases, notably DYRK1a (dual-specificity tyrosine-phosphorylated and -regulated kinase), PIM (provirus integration site for Moloney murine leukaemia virus) 1, 2 and 3, HIPK2 (homeodomain-interacting protein kinase-2), MNK1 [MAPK (mitogen-activated protein kinase)-interacting kinase 1], ERK8 (extracellular-signal-regulated kinase 8) and PKD1 (protein kinase D 1), which conversely tend to be inhibited as drastically as CK2 by commercially available CK2 inhibitors. The determination of the crystal structure of a complex between quinalizarin and CK2alpha subunit highlights the relevance of polar interactions in stabilizing the binding, an unusual characteristic for a CK2 inhibitor, and disclose other structural features which may account for the narrow selectivity of this compound. Tested on Jurkat cells, quinalizarin proved able to inhibit endogenous CK2 and to induce apoptosis more efficiently than the commonly used CK2 inhibitors TBB (4,5,6,7-tetrabromo-1H-benzotriazole) and DMAT (2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole). PMID:19432557

  18. An inhibitor of Janus kinase 2 prevents polycythemia in mice.

    Science.gov (United States)

    Mathur, Anjili; Mo, Jan-Rung; Kraus, Manfred; O'Hare, Erin; Sinclair, Peter; Young, Jonathan; Zhao, Shuxia; Wang, Yuxun; Kopinja, Johnny; Qu, Xianlu; Reilly, John; Walker, Deborah; Xu, Lin; Aleksandrowicz, Daniel; Marshall, Gary; Scott, Martin L; Kohl, Nancy E; Bachman, Eric

    2009-08-15

    Polycythemia vera (PV) is a myeloproliferative disorder characterized by increased red cell mass and splenomegaly in the absence of secondary causes [Tefferi A., Spivak J.L., Polycythemia vera: scientific advances and current practice. Semin Hematol 2005;42(4):206-20.]. Recently, several laboratories have discovered that the vast majority of patients with PV carry a single, activating mutation (V617F) in the pseudokinase domain of Janus kinase 2 (Jak2) [Zhao R, Xing S, Li Z, Fu X, Li Q, Krantz SB, et al., Identification of an acquired JAK2 mutation in polycythemia vera. J Biol Chem 2005;280(24):22788-92; James C, Ugo V, Le Couédic JP, Staerk J, Delhommeau F, Lacout C, et al., A unique clonal JAK2 mutation leading to constitutive signalling causes polycythemia vera. Nature 2005;434(7037):1144-8; Kralovics R, Passamonti F, Buser AS, Teo SS, Tiedt R, Passweg JR, et al., A gain-of-function mutation of JAK2 in myeloproliferative disorders. N Engl J Med 2005;352(17):1779-90; Levine RL, Wadleigh M, Cools J, Ebert BL, Wernig G, Huntly BJ, et al., Activating mutation in the tyrosine kinase JAK2 in polycythemia vera, essential thrombocythemia, and myeloid metaplasia with myelofibrosis. Cancer Cell 2005;7(4):387-97.]. This discovery has spurred interest in developing therapies for PV via inhibition of Jak2. We induced polycythemia in mice by administering high dose recombinant erythropoietin (Epo) and determined that administration recapitulates almost all of the major and minor diagnostic features of human PV. We then tested a selective, small molecule inhibitor of Jak2 (Jak2i) and showed that this treatment prevents polycythemia. This prevention of polycythemia was accompanied by lower hematocrits, reduced spleen sizes and reductions in Stat5 phosphorylation (pStat5). Surprisingly, Epo rapidly (discovery. We conclude that inhibition of Jak2 prevents polycythemia in mice, and furthermore present this model as an efficient tool for the discovery of drugs that effectively

  19. Crystal Structure of the MAP3K TAO2 Kinase Domain Bound by an Inhibitor Staurosporine

    Institute of Scientific and Technical Information of China (English)

    Tian-Jun ZHOU; Li-Guang SUN; Yan GAO; Elizabeth J. GOLDSMITH

    2006-01-01

    Mitogen-activated protein kinase (MAPK) signal transduction pathways are ubiquitous in eukaryotic cells, which transfer signals from the cell surface to the nucleus, controlling multiple cellular programs. MAPKs are activated by MAPK kinases [MAP2Ks or MAP/extracellular signal-regulated kinase (ERK) kinases (MEK)], which in turn are activated by MAPK kinase kinases (MAP3Ks). TAO2 is a MAP3K level kinase that activates the MAP2Ks MEK3 and MEK6 to activate p38 MAPKs. Because p38 MAPKs are key regulators of expression of inflammatory cytokines, they appear to be involved in human diseases such as asthma and autoimmunity. As an upstream activator of p38s, TAO2 represents a potential drug target. Here we report the crystal structure of active TAO2 kinase domain in complex with staurosporine, a broadrange protein kinase inhibitor that inhibits TAO2 with an IC50 of 3 μM. The structure reveals that staurosporine occupies the position where the adenosine of ATP binds in TAO2, and the binding of the inhibitor mimics many features of ATP binding. Both polar and nonpolar interactions contribute to the enzyme-inhibitor recognition. Staurosporine induces conformational changes in TAO2 residues that surround the inhibitor molecule, but causes very limited global changes in the kinase. The structure provides atomic details for TAO2-staurosporine interactions, and explains the relatively low potency of staurosporine against TAO2. The structure presented here should aid in the design of inhibitors specific to TAO2 and related kinases.

  20. Identification of a novel inhibitor of JAK2 tyrosine kinase by structure-based virtual screening

    OpenAIRE

    KISS, Róbert; Polgár, Tímea; Kirabo, Annet; Sayyah, Jacqueline; Figueroa, Nicholas C.; List, Alan F.; Sokol, Lubomir; Zuckerman, Kenneth S.; Gali, Meghanath; Bisht, Kirpal S.; Sayeski, Peter P.; Keserű, György M.

    2009-01-01

    Janus kinase 2 (JAK2) plays a crucial role in the pathomechanism of myeloproliferative disorders and hematologic malignancies. A somatic mutation of JAK2 (Val617Phe) was previously shown to occur in 98% of patients with polycythemia vera and 50% of patients with essential thrombocythemia and primary myelofibrosis. Thus, effective JAK2 kinase inhibitors may be of significant therapeutic importance. Here, we applied a structure-based virtual screen to identify novel JAK2 inhibitors. One JAK2 in...

  1. Methods for Investigation of Targeted Kinase Inhibitor Therapy using Chemical Proteomics and Phosphorylation Profiling

    OpenAIRE

    Fang, Bin; Haura, Eric B.; Smalley, Keiran S.; Eschrich, Steven A.; Koomen, John M.

    2010-01-01

    Phosphorylation acts as a molecular switch for many regulatory events in signaling pathways that drive cell division, proliferation, and apoptosis. Because of the critical nature of these protein post-translational modifications in cancer, drug development programs often focus on inhibitors for kinases and phosphatases, which control protein phosphorylation. Numerous kinase inhibitors have entered clinical use, but prediction of their efficacy and a molecular basis for patient response remain...

  2. PCI-32765, the First BTK (Bruton’s Tyrosine Kinase) Inhibitor in Clinical Trials

    OpenAIRE

    Brown, Jennifer R

    2013-01-01

    Ibrutinib is a potent covalent kinase inhibitor that targets BTK. BTK, or Bruton’s tyrosine kinase, is an obvious target for therapy of B cell diseases because inactivating mutations lead to B cell aplasia in humans and the disease X-linked agammaglobulinemia. Ibrutinib has modest cytotoxicity against CLL cells in vitro but also blocks trophic stimuli from the microenvironment. As with other inhibitors of the BCR pathway, ibrutinib causes rapid nodal reduction and response associated with rap...

  3. Progesterone receptor isoforms PRA and PRB differentially contribute to breast cancer cell migration through interaction with focal adhesion kinase complexes.

    Science.gov (United States)

    Bellance, Catherine; Khan, Junaid A; Meduri, Geri; Guiochon-Mantel, Anne; Lombès, Marc; Loosfelt, Hugues

    2013-05-01

    Progesterone receptor (PR) and progestins affect mammary tumorigenesis; however, the relative contributions of PR isoforms A and B (PRA and PRB, respectively) in cancer cell migration remains elusive. By using a bi-inducible MDA-MB-231 breast cancer cell line expressing PRA and/or PRB, we analyzed the effect of conditional PR isoform expression. Surprisingly, unliganded PRB but not PRA strongly enhanced cell migration as compared with PR(-) cells. 17,21-Dimethyl-19-norpregna-4,9-dien-3,20-dione (R5020) progestin limited this effect and was counteracted by the antagonist 11β-(4-dimethyl-amino)-phenyl-17β-hydroxy-17-(1-propynyl)-estra-4,9-dien-3-one (RU486). Of importance, PRA coexpression potentiated PRB-mediated migration, whereas PRA alone was ineffective. PR isoforms differentially regulated expressions of major players of cell migration, such as urokinase plasminogen activator (uPA), its inhibitor plasminogen activator inhibitor type 1, uPA receptor (uPAR), and β1-integrin, which affect focal adhesion kinase (FAK) signaling. Moreover, unliganded PRB but not PRA enhanced FAK Tyr397 phosphorylation and colocalized with activated FAK in cell protrusions. Because PRB, as well as PRA, coimmunoprecipitated with FAK, both isoforms can interact with FAK complexes, depending on their respective nucleocytoplasmic trafficking. In addition, FAK degradation was coupled to R5020-dependent turnovers of PRA and PRB. Such an effect of PRB/PRA expression on FAK signaling might thus affect adhesion/motility, underscoring the implication of PR isoforms in breast cancer invasiveness and metastatic evolution with underlying therapeutic outcomes.

  4. The Discovery of Aurora Kinase Inhibitor by Multi-Docking-Based Virtual Screening

    Directory of Open Access Journals (Sweden)

    Jun-Tae Kim

    2014-11-01

    Full Text Available We report the discovery of aurora kinase inhibitor using the fragment-based virtual screening by multi-docking strategy. Among a number of fragments collected from eMololecules, we found four fragment molecules showing potent activity (>50% at 100 μM against aurora kinase. Based on the explored fragment scaffold, we selected two compounds in our synthesized library and validated the biological activity against Aurora kinase.

  5. The Discovery of Aurora Kinase Inhibitor by Multi-Docking-Based Virtual Screening

    OpenAIRE

    Jun-Tae Kim; Seo Hee Jung; Sun Young Kang; Chung-Kyu Ryu; Nam Sook Kang

    2014-01-01

    We report the discovery of aurora kinase inhibitor using the fragment-based virtual screening by multi-docking strategy. Among a number of fragments collected from eMololecules, we found four fragment molecules showing potent activity (>50% at 100 μM) against aurora kinase. Based on the explored fragment scaffold, we selected two compounds in our synthesized library and validated the biological activity against Aurora kinase.

  6. The Mussel Adhesive Protein (Mefp-1) : A GREEN Corrosion Inhibitor

    OpenAIRE

    Zhang, Fan

    2013-01-01

    Corrosion of metallic materials is a natural process, and our study shows that even in an alkaline environment severe corrosion may occur on a carbon steel surface. While corrosion cannot be stopped it can be retarded. Many of the traditional anti-corrosion approaches such as the chromate process are effective but hazardous to the environment and human health. Mefp-1, a protein derived from blue mussel byssus, is well known for its extraordinary adhesion and film forming properties. Moreover,...

  7. Template-Based de Novo Design for Type II Kinase Inhibitors and Its Extented Application to Acetylcholinesterase Inhibitors

    Directory of Open Access Journals (Sweden)

    Bo-Han Su

    2013-10-01

    Full Text Available There is a compelling need to discover type II inhibitors targeting the unique DFG-out inactive kinase conformation since they are likely to possess greater potency and selectivity relative to traditional type I inhibitors. Using a known inhibitor, such as a currently available and approved drug or inhibitor, as a template to design new drugs via computational de novo design is helpful when working with known ligand-receptor interactions. This study proposes a new template-based de novo design protocol to discover new inhibitors that preserve and also optimize the binding interactions of the type II kinase template. First, sorafenib (Nexavar® and nilotinib (Tasigna®, two type II inhibitors with different ligand-receptor interactions, were selected as the template compounds. The five-step protocol can reassemble each drug from a large fragment library. Our procedure demonstrates that the selected template compounds can be successfully reassembled while the key ligand-receptor interactions are preserved. Furthermore, to demonstrate that the algorithm is able to construct more potent compounds, we considered kinase inhibitors and other protein dataset, acetylcholinesterase (AChE inhibitors. The de novo optimization was initiated using a template compound possessing a less than optimal activity from a series of aminoisoquinoline and TAK-285 inhibiting type II kinases, and E2020 derivatives inhibiting AChE respectively. Three compounds with greater potency than the template compound were discovered that were also included in the original congeneric series. This template-based lead optimization protocol with the fragment library can help to design compounds with preferred binding interactions of known inhibitors automatically and further optimize the compounds in the binding pockets.

  8. Role of Cbl-associated protein/ponsin in receptor tyrosine kinase signaling and cell adhesion

    Directory of Open Access Journals (Sweden)

    Ritva Tikkanen

    2012-10-01

    Full Text Available The Cbl-associated protein/ponsin (CAP is an adaptor protein that contains a so-called Sorbin homology (SoHo domain and three Src homology 3 (SH3 domains which are engaged in diverse protein-protein interactions. CAP has been shown to function in the regulation of the actin cytoskeleton and cell adhesion and to be involved in the differentiation of muscle cells and adipocytes. In addition, it participates in signaling pathways through several receptor tyrosine kinases such as insulin and neurotrophin receptors. In the last couple of years, several studies have shed light on the details of these processes and identified novel interaction partners of CAP. In this review, we summarize these recent findings and provide an overview on the function of CAP especially in cell adhesion and membrane receptor signaling.

  9. Mitogen-activated protein kinase (MAPK pathway regulates branching by remodeling epithelial cell adhesion.

    Directory of Open Access Journals (Sweden)

    Anneliis Ihermann-Hella

    2014-03-01

    Full Text Available Although the growth factor (GF signaling guiding renal branching is well characterized, the intracellular cascades mediating GF functions are poorly understood. We studied mitogen-activated protein kinase (MAPK pathway specifically in the branching epithelia of developing kidney by genetically abrogating the pathway activity in mice lacking simultaneously dual-specificity protein kinases Mek1 and Mek2. Our data show that MAPK pathway is heterogeneously activated in the subset of G1- and S-phase epithelial cells, and its tissue-specific deletion results in severe renal hypodysplasia. Consequently to the deletion of Mek1/2, the activation of ERK1/2 in the epithelium is lost and normal branching pattern in mutant kidneys is substituted with elongation-only phenotype, in which the epithelium is largely unable to form novel branches and complex three-dimensional patterns, but able to grow without primary defects in mitosis. Cellular characterization of double mutant epithelium showed increased E-cadherin at the cell surfaces with its particular accumulation at baso-lateral locations. This indicates changes in cellular adhesion, which were revealed by electron microscopic analysis demonstrating intercellular gaps and increased extracellular space in double mutant epithelium. When challenged to form monolayer cultures, the mutant epithelial cells were impaired in spreading and displayed strong focal adhesions in addition to spiky E-cadherin. Inhibition of MAPK activity reduced paxillin phosphorylation on serine 83 while remnants of phospho-paxillin, together with another focal adhesion (FA protein vinculin, were augmented at cell surface contacts. We show that MAPK activity is required for branching morphogenesis, and propose that it promotes cell cycle progression and higher cellular motility through remodeling of cellular adhesions.

  10. Ruxolitinib: An Oral Janus Kinase 1 and Janus Kinase 2 Inhibitor in the Management of Myelofibrosis

    Science.gov (United States)

    Verstovsek, Srdan

    2016-01-01

    Myelofibrosis (MF), polycythemia vera (PV), and essential thrombocythemia (ET) are referred to as the classic Philadelphia chromosome (BCR-ABL1)-negative myeloproliferative neoplasms. Although each has distinct pathologic features, all 3 display alterations in Janus kinase (JAK) signal transduction activator of transcription signaling. Myelofibrosis is the most serious of the 3, associated with shortened survival (median survival, 5–7 years); bone marrow failure with anemia; progressive splenomegaly; and chronic, burdensome symptoms, including fatigue, night sweats, itching, abdominal discomfort, loss of appetite/early satiety, unintentional weight loss, and bone, chest, and abdominal pain. Treatments for MF have been mainly palliative, with the exception of allogeneic stem cell transplantation, which, although potentially curative, is feasible only in a small subpopulation of patients. In November 2011, ruxolitinib, an inhibitor of JAK1 and JAK2, was approved by the US Food and Drug Administration for the treatment of intermediate- or high-risk MF, including primary MF, post-PV MF, and post-ET MF. In clinical trials, ruxolitinib was shown to reduce spleen volume and improve MF-related symptoms and quality-of-life measures. Evidence also suggests that ruxolitinib therapy has a survival advantage over placebo and best available therapy. Thrombocytopenia and anemia were the most common adverse events with treatment. Ongoing trials are assessing the efficacy and safety of ruxolitinib therapy in patients with PV and ET. PMID:23391678

  11. Exploiting the repertoire of CK2 inhibitors to target DYRK and PIM kinases.

    Science.gov (United States)

    Cozza, Giorgio; Sarno, Stefania; Ruzzene, Maria; Girardi, Cristina; Orzeszko, Andrzej; Kazimierczuk, Zygmunt; Zagotto, Giuseppe; Bonaiuto, Emanuela; Di Paolo, Maria Luisa; Pinna, Lorenzo A

    2013-07-01

    Advantage has been taken of the relative promiscuity of commonly used inhibitors of protein kinase CK2 to develop compounds that can be exploited for the selective inhibition of druggable kinases other than CK2 itself. Here we summarize data obtained by altering the scaffold of CK2 inhibitors to give rise to novel selective inhibitors of DYRK1A and to a powerful cell permeable dual inhibitor of PIM1 and CK2. In the former case one of the new compounds, C624 (naphto [1,2-b]benzofuran-5,9-diol) displays a potency comparable to that of the first-in-class DYRK1A inhibitor, harmine, lacking however the drawback of drastically inhibiting monoamine oxidase-A (MAO-A) as harmine does. On the other hand the promiscuous CK2 inhibitor 4,5,6,7-tetrabromo-1H-benzimidazole (TBI,TBBz) has been derivatized with a sugar moiety to generate a 1-(β-D-2'-deoxyribofuranosyl)-4,5,6,7-tetrabromo-1H-benzimidazole (TDB) compound which inhibits PIM1 and CK2 with comparably high efficacy (IC50 values<100nM) and remarkable selectivity. TDB, unlike other dual PIM1/CK2 inhibitors described in the literature is readily cell permeable and displays a cytotoxic effect on cancer cells consistent with concomitant inhibition of both its onco-kinase targets. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012). PMID:23360763

  12. ATP competitive protein kinase C inhibitors demonstrate distinct state-dependent inhibition.

    Directory of Open Access Journals (Sweden)

    Ida M Smith

    Full Text Available We previously reported that some ATP competitive protein kinase C (PKC inhibitors are either competitive or uncompetitive inhibitors with respect to substrate peptides. In this report, we demonstrate how the interactions between PKC and inhibitors change PKC activation kinetics. A substrate competitive inhibitor, bisindolylmaleimide I, targets activated PKC and stabilizes PKC in the activated conformation. This leads to transient activation and prolonged deactivation of PKC in the presence of bisindolylmaleimide I. In contrast, an uncompetitive substrate inhibitor, bisindolylmaleimide IV, targets quiescent PKC and stabilizes PKC in the quiescent conformation, which generates slower activation and suppressed translocation upon activation of PKC.

  13. Jadomycin B, an Aurora-B kinase inhibitor discovered through virtual screening

    Institute of Scientific and Technical Information of China (English)

    Da Huafu; Jing Zhang; Jian Tingzheng; Yan Li; Ke Qianyang; Yan Changwang; Shu Yisi

    2008-01-01

    @@ Aurora kinases are clearly implicated in tumorgenesis and have emerged as promising targets for cancer therapy in recent years. In a virtual screening attempt, 22 compounds were identified from nearly 15,000 microbial natural products as potential small-molecule inhibitors of human Aurora-B kinase. When tested in yeast models, 2 compounds (one is Jadomycin B) showed preferential inhibition of ipll-321 (yeast Aurora kinase temperature sensitive mutant) than wild type yeast cell, suggesting these compounds are true Aurora kinase inhibitors. Further in vitro biochemical assay using purified recombinant Aurora-B kinase showed Jadomycin B inhibits Aurora-B activity in a dose-dependent fashion while two Jadomycin congeners, Jadomycin S and T, showed no activity.

  14. Effect of cycline-dependent kinase and matrix metalloproteinase inhibitors on hematopoietic and leukemic cells

    OpenAIRE

    Song, Hairong

    2008-01-01

    Rapid advances in molecular and cellular biology have improved the understanding of the mechanisms involved in leukemia development. Cyclin-dependent kinases (CDKs) and matrix metalloproteinases (MMPs) have been suggested as potential therapeutic targets and a number of pharmacologic inhibitors of CDKs and MMPs have been developed. This thesis aimed to increase knowledge about pharmacokinetics and cytotoxic effects of the CDK inhibitor roscovitine and MMP inhibitors from...

  15. Mycosporine-Like Amino Acids Promote Wound Healing through Focal Adhesion Kinase (FAK and Mitogen-Activated Protein Kinases (MAP Kinases Signaling Pathway in Keratinocytes

    Directory of Open Access Journals (Sweden)

    Yun-Hee Choi

    2015-11-01

    Full Text Available Mycosporine-like amino acids (MAAs are secondary metabolites found in diverse marine, freshwater, and terrestrial organisms. Evidence suggests that MAAs have several beneficial effects on skin homeostasis such as protection against UV radiation and reactive oxygen species (ROS. In addition, MAAs are also involved in the modulation of skin fibroblasts proliferation. However, the regulatory function of MAAs on wound repair in human skin is not yet clearly elucidated. To investigate the roles of MAAs on the wound healing process in human keratinocytes, three MAAs, Shinorine (SH, Mycosporine-glycine (M-Gly, and Porphyra (P334 were purified from Chlamydomonas hedlyei and Porphyra yezoensis. We found that SH, M-Gly, and P334 have significant effects on the wound healing process in human keratinocytes and these effects were mediated by activation of focal adhesion kinases (FAK, extracellular signal-regulated kinases (ERK, and c-Jun N-terminal kinases (JNK. These results suggest that MAAs accelerate wound repair by activating the FAK-MAPK signaling pathways. This study also indicates that MAAs can act as a new wound healing agent and further suggests that MAAs might be a novel biomaterial for wound healing therapies.

  16. Induction of multiple sclerosis and response to tyrosine kinase inhibitors.

    Science.gov (United States)

    Moawad, Emad Y

    2014-10-01

    The goal of this work is to determine the role of the autoimmune cells in multiple sclerosis (MS) induction and the immunomodulatory mechanism of therapy with tyrosine kinase inhibitors (TKIs) in MS attenuation. Samples (5 × 10(5) cells per well) of C6 and primary rat astrocytes were stimulated with 10 ng/mL of platelet-derived growth factor (PDGFbb) as a positive control forming a mouse model of MS. PDGFbb was added to the astrocytes in the absence or presence of 0.1 and 1 μM of imatinib. Proliferation of C6 and primary rat astrocytes samples were assessed for samples staging by the addition of 1 μCi of (3)H-thymidine per well. Samples of RAW 264.7 cells were stimulated for 48 h with 10 ng/mL of PDGFbb in the absence or presence of 0.1 and 1 μM of sorafenib. Tumour necrotic factor (TNF) levels in culture supernatants from RAW 264.7 cells were measured by ELISA. The histologic grade (HG) and the level of TNF of the mouse model of MS was 1/5 and 5 times respectively of those in the control one to clarify that MS induction is due to a major decrease in HG inversely proportional to the accompanied increase in TNF level perpetuating local inflammation and demyelination in MS lesion. The addition of 0.1 and 1 μM doses of imatinib increased HG of the mouse model of MS by 6 and 11 times respectively while 0.1 and 1 μM doses of sorafenib decreased TNF level to be 1/2 and 1/5 of that in the mouse model of MS respectively restoring normal rate of TNF level of normal lesion to show that HGand TNF level would be strongly inversely correlated (r = -0.99) in attenuating MS effectively by TKIs therapy but not in an inverse proportion as in MS induction. PMID:25298631

  17. Role of Titanium Surface Topography and Surface Wettability on Focal Adhesion Kinase Mediated Signaling in Fibroblasts

    Directory of Open Access Journals (Sweden)

    Douglas W. Hamilton

    2011-05-01

    Full Text Available Changes of titanium surface roughness and surface free energy may influence protein absorption that increases cell differentiation through activation of focal adhesion kinase related pathways. However, the influence of titanium surface roughness and hydrophilicity on fibroblast behavior is not well understood. The aim of this study was to investigate the influence of topography and hydrophilicity on fibroblast attachment, spreading, morphology, intracellular signaling, proliferation, and collagen I mRNA levels. Using a cellular FAK knockout (FAK−/− model and wild-type (WT controls, we also investigated the contribution of adhesion in fibroblasts cultured on smooth (PT, sand-blasted, large grit, acid-etched (SLA and hydrophilic SLA topographies. Loss of FAK did not significantly affect fibroblast attachment to any surface, but SLA and hydrophilic SLA surface attenuated spreading of WT cells significantly more than FAK−/− fibroblasts. Both FAK−/− and WT cells formed numerous focal adhesions on PT surfaces, but significantly less on SLA and hydrophilic SLA surfaces. In WT cells, phosphorylation levels of FAK were lower on SLA and hydrophilic SLA in comparison with PT 24 h post seeding. Labeling of cells with antibodies to cortactin showed that FAK−/−cells contained significantly more cortactin-rich focal adhesion in comparison with WT cells on PT surfaces, but not on SLA or hydrophilic SLA. ERK 1/2 phosphorylation was highest in WT cells on all surfaces which correlated with collagen I expression levels. We conclude that fibroblasts are sensitive to changes in surface roughness and hydrophilicity, with adhesive interactions mediated through FAK, an important modulator of fibroblast response.

  18. Random mutagenesis reveals residues of JAK2 critical in evading inhibition by a tyrosine kinase inhibitor.

    Directory of Open Access Journals (Sweden)

    Michael R Marit

    Full Text Available BACKGROUND: The non-receptor tyrosine kinase JAK2 is implicated in a group of myeloproliferative neoplasms including polycythemia vera, essential thrombocythemia, and primary myelofibrosis. JAK2-selective inhibitors are currently being evaluated in clinical trials. Data from drug-resistant chronic myeloid leukemia patients demonstrate that treatment with a small-molecule inhibitor generates resistance via mutation or amplification of BCR-ABL. We hypothesize that treatment with small molecule inhibitors of JAK2 will similarly generate inhibitor-resistant mutants in JAK2. METHODOLOGY: In order to identify inhibitor-resistant JAK2 mutations a priori, we utilized TEL-JAK2 to conduct an in vitro random mutagenesis screen for JAK2 alleles resistant to JAK Inhibitor-I. Isolated mutations were evaluated for their ability to sustain cellular growth, stimulate downstream signaling pathways, and phosphorylate a novel JAK2 substrate in the presence of inhibitor. CONCLUSIONS: Mutations were found exclusively in the kinase domain of JAK2. The panel of mutations conferred resistance to high concentrations of inhibitor accompanied by sustained activation of the Stat5, Erk1/2, and Akt pathways. Using a JAK2 substrate, enhanced catalytic activity of the mutant JAK2 kinase was observed in inhibitor concentrations 200-fold higher than is inhibitory to the wild-type protein. When testing the panel of mutations in the context of the Jak2 V617F allele, we observed that a subset of mutations conferred resistance to inhibitor, validating the use of TEL-JAK2 in the initial screen. These results demonstrate that small-molecule inhibitors select for JAK2 inhibitor-resistant alleles, and the design of next-generation JAK2 inhibitors should consider the location of mutations arising in inhibitor-resistant screens.

  19. Crystal structure of a human cyclin-dependent kinase 6 complexwith a flavonol inhibitor, Fisetin

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Heshu; Chang, Debbie J.; Baratte, Blandine; Meijer, Laurent; Schulze-Gahmen, Ursula

    2005-01-10

    Cyclin-dependent kinases (CDKs) play a central role in cell cycle control, apoptosis, transcription and neuronal functions. They are important targets for the design of drugs with anti-mitotic and/or anti-neurodegenerative effects. CDK4 and CDK6 form a subfamily among the CDKs in mammalian cells, as defined by sequence similarities. Compared to CDK2 and CDK5, structural information on CDK4 and CDK6 is sparse. We describe here the crystal structure of human CDK6 in complex with a viral cyclin and a flavonol inhibitor, fisetin. Fisetin binds to the active form of CDK6, forming hydrogen bonds with the side chains of residues in the binding pocket that undergo large conformational changes during CDK activation by cyclin binding. The 4-keto group and the 3-hydroxyl group of fisetin are hydrogen bonded with the backbone in the hinge region between the N-terminal and C-terminal kinase domain, as has been observed for many CDK inhibitors. However, CDK2 and HCK kinase in complex with other flavone inhibitors such as quercetin and flavopiridol showed a different binding mode with the inhibitor rotated by about 180. The structural information of the CDK6-fisetin complex is correlated with the binding affinities of different flavone inhibitors for CDK6. This complex structure is the first description of an inhibitor complex with a kinase from the CDK4/6 subfamily and can provide a basis for selecting and designing inhibitor compounds with higher affinity and specificity.

  20. Glycosylation inhibitors efficiently inhibit P-selectin-mediated cell adhesion to endothelial cells.

    Science.gov (United States)

    Ghoshal, Pushpankur; Rajendran, Mythilypriya; Odo, Nadine; Ikuta, Tohru

    2014-01-01

    Adhesion molecules play a critical role in the adhesive interactions of multiple cell types in sickle cell disease (SCD). We previously showed that anti-P-selectin aptamer efficiently inhibits cell adhesion to endothelial cells (ECs) and permits SCD mice to survive hypoxic stress. In an effort to discover new mechanisms with which to inhibit P-selectin, we examined the role of glycosylation. P-selectin is a 90 kDa protein but was found to migrate as 90 and 140 kDa bands on gel electrophoresis. When P-selectin isolated from ECs was digested with peptide N-glycosidase F, but not O-glycosidase, the 140 kDa band was lost and the 90 kDa band was enhanced. Treatment of ECs with tunicamycin, an N-glycosylation inhibitor, suppressed CD62P (P-selectin) expression on the cell surface as well as the 140 kDa form in the cytoplasm. These results indicate that the 140 kDa band is N-glycosylated and glycosylation is critical for cell surface expression of P-selectin in ECs. Thrombin, which stimulates P-selectin expression on ECs, induced AKT phosphorylation, whereas tunicamycin inhibited AKT phosphorylation, suggesting that AKT signaling is involved in the tunicamycin-mediated inhibition of P-selectin expression. Importantly, the adhesion of sickle red blood cells (sRBCs) and leukocytes to ECs induced by thrombin or hypoxia was markedly inhibited by two structurally distinct glycosylation inhibitors; the levels of which were comparable to that of a P-selectin monoclonal antibody which most strongly inhibited cell adhesion in vivo. Knockdown studies of P-selectin using short-hairpin RNAs in ECs suppressed sRBC adhesion, indicating a legitimate role for P-selectin in sRBC adhesion. Together, these results demonstrate that P-selectin expression on ECs is regulated in part by glycosylation mechanisms and that glycosylation inhibitors efficiently reduce the adhesion of sRBCs and leukocytes to ECs. Glycosylation inhibitors may lead to a novel therapy which inhibits cell adhesion in SCD.

  1. MOLECULAR MODELING AND DRUG DISCOVERY OF POTENTIAL INHIBITORS FOR ANTICANCER TARGET GENE MELK (MATERNAL EMBRYONIC LEUCINE ZIPPER KINASE

    Directory of Open Access Journals (Sweden)

    Sabitha. K

    2011-12-01

    Full Text Available Maternal embryonic leucine zipper kinase (MELK, a member of the AMP serine/threonine kinase family, exhibits multiple features consistent with the potential utility of this gene as an anticancer target. Reports show that MELK functions as a cancer-specific protein kinase, and that down-regulation of MELK results in growth suppression of breast cancer cells. There are many inhibitors which bind to kinases and are in clinical trials too. In our study we have taken a library of different inhibitors and docked those using GLIDE Induced Fit. From docking result we can conclude that Syk inhibitor II, Rho kinase inhibitor IV, p38 MAP Kinase Inhibitor III, HA 1004, Dihydrochloride and IKK -2 inhibitor VI have good binding affinity towards MELK and may have anticancer activity.

  2. Reduced Proteolytic Shedding of Receptor Tyrosine Kinases is a Post-Translational Mechanism of Kinase Inhibitor Resistance

    Science.gov (United States)

    Miller, Miles A.; Oudin, Madeleine J.; Sullivan, Ryan J.; Wang, Stephanie J.; Meyer, Aaron S.; Im, Hyungsoon; Frederick, Dennie T.; Tadros, Jenny; Griffith, Linda G.; Lee, Hakho; Weissleder, Ralph; Flaherty, Keith T.; Gertler, Frank B.; Lauffenburger, Douglas A.

    2016-01-01

    Kinase inhibitor resistance often involves upregulation of poorly understood “bypass” signaling pathways. Here, we show that extracellular proteomic adaptation is one path to bypass signaling and drug resistance. Proteolytic shedding of surface receptors, which can provide negative feedback on signaling activity, is blocked by kinase inhibitor treatment and enhances bypass signaling. In particular, MEK inhibition broadly decreases shedding of multiple receptor tyrosine kinases (RTKs) including HER4, MET, and most prominently AXL, an ADAM10 and ADAM17 substrate, thus increasing surface RTK levels and mitogenic signaling. Progression-free survival of melanoma patients treated with clinical BRAF/MEK inhibitors inversely correlates with RTK shedding reduction following treatment, as measured non-invasively in blood plasma. Disrupting protease inhibition by neutralizing TIMP1 improves MAPK inhibitor efficacy, and combined MAPK/AXL inhibition synergistically reduces tumor growth and metastasis in xenograft models. Altogether, extracellular proteomic rewiring through reduced RTK shedding represents a surprising mechanism for bypass signaling in cancer drug resistance. PMID:26984351

  3. Distinct biophysical mechanisms of focal adhesion kinase mechanoactivation by different extracellular matrix proteins.

    Science.gov (United States)

    Seong, Jihye; Tajik, Arash; Sun, Jie; Guan, Jun-Lin; Humphries, Martin J; Craig, Susan E; Shekaran, Asha; García, Andrés J; Lu, Shaoying; Lin, Michael Z; Wang, Ning; Wang, Yingxiao

    2013-11-26

    Matrix mechanics controls cell fate by modulating the bonds between integrins and extracellular matrix (ECM) proteins. However, it remains unclear how fibronectin (FN), type 1 collagen, and their receptor integrin subtypes distinctly control force transmission to regulate focal adhesion kinase (FAK) activity, a crucial molecular signal governing cell adhesion/migration. Here we showed, using a genetically encoded FAK biosensor based on fluorescence resonance energy transfer, that FN-mediated FAK activation is dependent on the mechanical tension, which may expose its otherwise hidden FN synergy site to integrin α5. In sharp contrast, the ligation between the constitutively exposed binding motif of type 1 collagen and its receptor integrin α2 was surprisingly tension-independent to induce sufficient FAK activation. Although integrin α subunit determines mechanosensitivity, the ligation between α subunit and the ECM proteins converges at the integrin β1 activation to induce FAK activation. We further discovered that the interaction of the N-terminal protein 4.1/ezrin/redixin/moesin basic patch with phosphatidylinositol 4,5-biphosphate is crucial during cell adhesion to maintain the FAK activation from the inhibitory effect of nearby protein 4.1/ezrin/redixin/moesin acidic sites. Therefore, different ECM proteins either can transmit or can shield from mechanical forces to regulate cellular functions, with the accessibility of ECM binding motifs by their specific integrin α subunits determining the biophysical mechanisms of FAK activation during mechanotransduction.

  4. Protocadherin clusters and cell adhesion kinase regulate dendrite complexity through Rho GTPase

    Institute of Scientific and Technical Information of China (English)

    Lun Suo; Huinan Lu; Guoxin Ying; Mario R. Capecchi; Qiang Wu

    2012-01-01

    Dendritic patterning and spine morphogenesis are crucial for the assembly of neuronal circuitry to ensure normal brain development and synaptic connectivity as well as for understanding underlying mechanisms of neuropsychiatric diseases and cognitive impairments.The Rho GTPase family is essential for neuronal morphogenesis and synaptic plasticity by modulating and reorganizing the cytoskeleton.Here,we report that protocadherin (Pcdh) clusters and cell adhesion kinases (CAKs) play important roles in dendritic development and spine elaboration.The knockout of the entire Pcdhα cluster results in the dendritic simplification and spine loss in CA1 pyramidal neurons in vivo and in cultured primary hippocampal neurons in vitro.The knockdown of the whole Pcdhγ cluster or in combination with the Pcdhα knockout results in similar dendritic and spine defects in vitro.The overexpression of proline-rich tyrosine kinase 2 (Pyk2,also known as CAKβ,RAFTK,FAK2,and CADTK) recapitulates these defects and its knockdown rescues the phenotype.Moreover,the genetic deletion of the Pcdhα cluster results in phosphorylation and activation of Pyk2 and focal adhesion kinase (Fak) and the inhibition of Rho GTPases in vivo.Finally,the overexpression of PyK2 leads to inactivation of Rac1 and,conversely,the constitutive active Rac1 rescues the dendritic and spine morphogenesis defects caused by the knockout of the Pcdhα cluster and the knockdown of the Pcdhγ cluster.Thus,the involvement of the Pcdh-CAK-Rho GTPase pathway in the dendritic development and spine morphogenesis has interesting implications for proper assembly of neuronal connections in the brain.

  5. Janus kinases as targets for small molecule inhibitors

    OpenAIRE

    Kaczor, Jakub

    2010-01-01

    Many cytokines transduce signals by employing receptor/Janus kinase (Jak) complexes that, once activated, promote phosphorylation of several signaling proteins such as STAT transcription factors. The Jak/STAT pathway is normally tightly modulated by regulatory mechanisms preventing its over-activation. However, a number of genetic alterations in Jak kinase genes have been found in myeloproliferative neoplasms and leukemia that render the Jaks hyperactive and cytokine-independent. In the prese...

  6. Mesenchymal stem cells are sensitive to treatment with kinase inhibitors and ionizing radiation

    International Nuclear Information System (INIS)

    Mesenchymal stem cells (MSCs) can regenerate damaged tissues and may therefore be of importance for normal tissue repair after cancer treatment. Small molecule receptor kinase inhibitors (RKIs) have recently been introduced into cancer treatment. However, the influence of these drugs - particularly in combination with radiotherapy - on the survival of MSCs is largely unknown. The sensitivity of human primary MSCs from healthy volunteers and primary human fibroblast cells to small molecule kinase inhibitors of the vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ) receptors, as well to inhibitors of c-Kit, was examined in combination with ionizing radiation (IR); cell survival and proliferation were assessed. Expression patterns of different kinase receptors and ligands were investigated using gene arrays. MSCs were highly sensitive to the tyrosine kinase inhibitors SU14816 (imatinib) and SU11657 (sunitinib), but showed only moderate sensitivity to the selective TGFβ receptor 1 inhibitor LY2109761. Primary adult human fibroblasts were comparably resistant to all three inhibitors. The addition of IR had an additive or supra-additive effect in the MSCs, but this was not the case for differentiated fibroblasts. Proliferation was markedly reduced in MSCs following kinase inhibition, both with and without IR. Gene expression analysis revealed high levels of the PDGF α and β receptors, and lower levels of the TGFβ receptor 2 and Abl kinase. IR did not alter the expression of kinase receptors or their respective ligands in either MSCs or adult fibroblasts. These data show that MSCs are highly sensitive to RKIs and combination treatments incorporating IR. Expression analyses suggest that high levels of PDGF receptors may contribute to this effect. (orig.)

  7. Repurposing Kinase Inhibitors as Antiviral Agents to Control Influenza A Virus Replication.

    Science.gov (United States)

    Perwitasari, Olivia; Yan, Xiuzhen; O'Donnell, Jason; Johnson, Scott; Tripp, Ralph A

    2015-12-01

    Influenza A virus (IAV) infection causes seasonal epidemics of contagious respiratory illness that causes substantial morbidity and some mortality. Regular vaccination is the principal strategy for controlling influenza virus, although vaccine efficacy is variable. IAV antiviral drugs are available; however, substantial drug resistance has developed to two of the four currently FDA-approved antiviral drugs. Thus, new therapeutic approaches are being sought to reduce the burden of influenza-related disease. A high-throughput screen using a human kinase inhibitor library was performed targeting an emerging IAV strain (H7N9) in A549 cells. The inhibitor library contained 273 structurally diverse, active cell permeable kinase inhibitors with known bioactivity and safety profiles, many of which are at advanced stages of clinical development. The current study shows that treatment of human A549 cells with kinase inhibitors dinaciclib, flavopiridol, or PIK-75 exhibits potent antiviral activity against H7N9 IAV as well as other IAV strains. Thus, targeting host kinases can provide a broad-spectrum therapeutic approach against IAV. These findings provide a path forward for repurposing existing kinase inhibitors safely as potential antivirals, particularly those that can be tested in vivo and ultimately for clinical use. PMID:26192013

  8. Molecular Mechanism of Selectivity among G Protein-Coupled Receptor Kinase 2 Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Thal, David M.; Yeow, Raymond Y.; Schoenau, Christian; Huber, Jochen; Tesmer, John J.G. (Sanofi); (Michigan)

    2012-07-11

    G protein-coupled receptors (GPCRs) are key regulators of cell physiology and control processes ranging from glucose homeostasis to contractility of the heart. A major mechanism for the desensitization of activated GPCRs is their phosphorylation by GPCR kinases (GRKs). Overexpression of GRK2 is strongly linked to heart failure, and GRK2 has long been considered a pharmaceutical target for the treatment of cardiovascular disease. Several lead compounds developed by Takeda Pharmaceuticals show high selectivity for GRK2 and therapeutic potential for the treatment of heart failure. To understand how these drugs achieve their selectivity, we determined crystal structures of the bovine GRK2-G{beta}{gamma} complex in the presence of two of these inhibitors. Comparison with the apoGRK2-G{beta}{gamma} structure demonstrates that the compounds bind in the kinase active site in a manner similar to that of the AGC kinase inhibitor balanol. Both balanol and the Takeda compounds induce a slight closure of the kinase domain, the degree of which correlates with the potencies of the inhibitors. Based on our crystal structures and homology modeling, we identified five amino acids surrounding the inhibitor binding site that we hypothesized could contribute to inhibitor selectivity. However, our results indicate that these residues are not major determinants of selectivity among GRK subfamilies. Rather, selectivity is achieved by the stabilization of a unique inactive conformation of the GRK2 kinase domain.

  9. Heat shock protein 90β stabilizes focal adhesion kinase and enhances cell migration and invasion in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Xiangyang [Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Donghu District, Nanchang, Jiangxi 330006 (China); Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanchang University, Nanchang, Jiangxi 330006 (China); State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047 (China); Wang, Yao [Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Donghu District, Nanchang, Jiangxi 330006 (China); Liu, Chengmei [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, Jiangxi 330047 (China); Lu, Quqin [Department of Biostatistics and Epidemiology, School of Public Health, Nanchang University, Nanchang, Jiangxi 330006 (China); Liu, Tao [Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Donghu District, Nanchang, Jiangxi 330006 (China); Chen, Guoan [Department of Hematology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006 (China); Rao, Hai [Department of Molecular Medicine, University of Texas Health Science Center, San Antonio, TX 78229 (United States); Luo, Shiwen, E-mail: shiwenluo@ncu.edu.cn [Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Donghu District, Nanchang, Jiangxi 330006 (China)

    2014-08-01

    Focal adhesion kinase (FAK) acts as a regulator of cellular signaling and may promote cell spreading, motility, invasion and survival in malignancy. Elevated expression and activity of FAK frequently correlate with tumor cell metastasis and poor prognosis in breast cancer. However, the mechanisms by which the turnover of FAK is regulated remain elusive. Here we report that heat shock protein 90β (HSP90β) interacts with FAK and the middle domain (amino acids 233–620) of HSP90β is mainly responsible for this interaction. Furthermore, we found that HSP90β regulates FAK stability since HSP90β inhibitor 17-AAG triggers FAK ubiquitylation and subsequent proteasome-dependent degradation. Moreover, disrupted FAK-HSP90β interaction induced by 17-AAG contributes to attenuation of tumor cell growth, migration, and invasion. Together, our results reveal how HSP90β regulates FAK stability and identifies a potential therapeutic strategy to breast cancer. - Highlights: • HSP90β protects FAK from degradation by the ubiquitin-proteasome pathway. • Inhibition of HSP90β or FAK attenuates tumorigenesis of breast cancer cells. • Genetic repression of HSP90β or FAK inhibits tumor cell migration and proliferation. • Inhibition of HSP90β or FAK interferes cell invasion and cytoskeleton.

  10. Small-molecule kinase inhibitors: an analysis of FDA-approved drugs

    DEFF Research Database (Denmark)

    Wu, Peng; Nielsen, Thomas Eiland; Clausen, Mads Hartvig

    2016-01-01

    Small-molecule kinase inhibitors (SMKIs), 28 of which are approved by the US Food and Drug Administration (FDA), have been actively pursued as promising targeted therapeutics. Here, we assess the key structural and physicochemical properties, target selectivity and mechanism of function, and...... therapeutic indications of these approved inhibitors. Our analysis showed that >30% of approved SMKIs have a molecule weight (MW) exceeding 500 and all have a total ring count of between three and five. The assumption that type II inhibitors tend to be more selective than type I inhibitors has been proved to...

  11. Benzofuran Small Molecules as Potential Inhibitors of Human Protein Kinases. A Review.

    Science.gov (United States)

    Kwiecień, Halina; Goszczyńska, Agata; Rokosz, Paulina

    2016-01-01

    Kinases are known to regulate the majority of human cellular processes such as communication, division, metabolism, survival and apoptosis therefore they can be promising targets in cancer diseases, viral infection and in other disorders. Small molecules acting as selective human protein kinase inhibitors are very attractive pharmacological targets. This review presents a number of examples of biologically active natural and synthetic benzo[b]furans and their derivatives, such as benzo[b]furan-2- and 3-ones, benzo[b]furan-2- and 3-carboxylic acids, as well as benzo[c]furans as potential inhibitors of various human protein kinases. The pathways of function and implication of the inhibitors in cancer and other diseases are discussed. PMID:26648467

  12. Neural cell adhesion molecule-stimulated neurite outgrowth depends on activation of protein kinase C and the Ras-mitogen-activated protein kinase pathway

    DEFF Research Database (Denmark)

    Kolkova, K; Novitskaya, V; Pedersen, N;

    2000-01-01

    , inhibitors of the nonreceptor tyrosine kinase p59(fyn), PLC, PKC and MEK and an activator of PKC, phorbol-12-myristate-13-acetate (PMA). MEK2 transfection rescued cells treated with all inhibitors. The same was found for PMA treatment, except when cells concomitantly were treated with the MEK inhibitor....... Arachidonic acid rescued cells treated with antibodies to the FGF receptor or the PLC inhibitor, but not cells in which the activity of PKC, p59(fyn), FAK, Ras, or MEK was inhibited. Interaction of NCAM with a synthetic NCAM peptide ligand, known to induce neurite outgrowth, was shown to stimulate...

  13. The kinase inhibitor tofacitinib in patients with rheumatoid arthritis: latest findings and clinical potential

    OpenAIRE

    Cutolo, Maurizio

    2013-01-01

    Macrophages, T and B cells, and neutrophils concentrate mainly into the synovial tissue of rheumatoid arthritis (RA) patients and produce several inflammatory mediators including cytokines. More recently, small molecule inhibitors of signalling mediators which have intracellular targets (mainly in T and B cells) such as the Janus kinase (JAK) family of tyrosine kinases have been introduced in RA treatment. The JAK family consist of four types: JAK1, JAK2, JAK3 and TyK2. In particular, JAK3 is...

  14. Selective Phosphorylation Inhibitor of Delta Protein Kinase C-Pyruvate Dehydrogenase Kinase Protein-Protein Interactions: Application for Myocardial Injury in Vivo.

    Science.gov (United States)

    Qvit, Nir; Disatnik, Marie-Hélène; Sho, Eiketsu; Mochly-Rosen, Daria

    2016-06-22

    Protein kinases regulate numerous cellular processes, including cell growth, metabolism, and cell death. Because the primary sequence and the three-dimensional structure of many kinases are highly similar, the development of selective inhibitors for only one kinase is challenging. Furthermore, many protein kinases are pleiotropic, mediating diverse and sometimes even opposing functions by phosphorylating multiple protein substrates. Here, we set out to develop an inhibitor of a selective protein kinase phosphorylation of only one of its substrates. Focusing on the pleiotropic delta protein kinase C (δPKC), we used a rational approach to identify a distal docking site on δPKC for its substrate, pyruvate dehydrogenase kinase (PDK). We reasoned that an inhibitor of PDK's docking should selectively inhibit the phosphorylation of only PDK without affecting phosphorylation of the other δPKC substrates. Our approach identified a selective inhibitor of PDK docking to δPKC with an in vitro Kd of ∼50 nM and reducing cardiac injury IC50 of ∼5 nM. This inhibitor, which did not affect the phosphorylation of other δPKC substrates even at 1 μM, demonstrated that PDK phosphorylation alone is critical for δPKC-mediated injury by heart attack. The approach we describe is likely applicable for the identification of other substrate-specific kinase inhibitors. PMID:27218445

  15. De novo design of VEGFR-2 tyrosine kinase inhibitors based on a linked-fragment approach.

    Science.gov (United States)

    Liu, Yi-Zhou; Wang, Xiao-Li; Wang, Xin-Ying; Yu, Ri-Lei; Liu, Dong-Qing; Kang, Cong-Min

    2016-09-01

    Vascular endothelial growth factor receptor-2 (VEGFR-2) tyrosine kinase inhibitors have been demonstrated to possess substantial antitumor activity. VEGFR-2 tyrosine kinase inhibitors are crucial for development of antitumor drugs. Based on the crystal structure of VEGFR-2 tyrosine kinase, a linked-fragment strategy was employed to design novel VEGFR-2 tyrosine kinase inhibitors, and 1000 compounds were generated in this process. Absorption, distribution, metabolism, excretion and toxicity (ADMET) were used to screen the 1000 compounds, and 59 compounds were acceptable. Scaffold hopping was then used for further screening, and only four compounds were obtained in this way. Then, the binding energy of the four molecules to VEGFR-2 tyrosine kinase was calculated using molecular docking, and their values were found to be lower than that of Sorafenib. Finally, molecular dynamics simulations were performed on the complex of the compound with the lowest binding energy with VEGFR-2 tyrosine kinase, and the binding model was analyzed. At the end, four chemical entities with novel structures were obtained, and were suggested for experimental testing in future studies. PMID:27558799

  16. Unique Cyclin-Dependent Kinase (CDK) Inhibitors at the ATP-site

    Institute of Scientific and Technical Information of China (English)

    LI Lin; LUNDGREN Karen; ESCOBAR Jorge; MINNICK Sharon price; HUBER Andrea; KOUDRIAKOVA Tatiana; ARRUDA Jeannie; SISSON Wes; AUST Robert M.; VERKHIVKER Gennady M.; SCHAFFER Lana; CHONG Wesley K. M.; ROSE Peter w.; LEWIS Cristrina T; DUVADIE Rohit K.; CHU Shao Song; YANG Y. Michelle; NONOMIYA Jim; TUCKER Kadthleen D.; KNIGHTON Daniel R.; FERRE RoseAnn

    2001-01-01

    @@ Control of the cell cycle could be applicable in new approaches for cancer chemotherapy. The cyclin-dependent kinases (CDK's) and their corresponding complexes with cyclins are regulatory enzymes for which we have discovered a novel small molecule series of inhibitors, with potencies in the nanomolar range and good selectivity for the CDK's versus other kinases. We will discuss structure-based drug design efforts with crystal structures of complexes with certain CDK's. Cellular effects and some preliminary examination of in vivo cancer efficacy by these inhibitors will also be discussed.

  17. Global effects of kinase inhibitors on signaling networks revealed by quantitative phosphoproteomics

    DEFF Research Database (Denmark)

    Pan, Cuiping; Olsen, Jesper V; Daub, Henrik;

    2009-01-01

    to identify the direct targets of kinase inhibitors upon affinity purification from cellular extracts. Here we introduce a complementary approach to evaluate the effects of kinase inhibitors on the entire cell signaling network. We used triple labeling SILAC (stable isotope labeling by amino acids in cell......-ABL, which is the cause of chronic myelogenous leukemia, affected nearly 1,000 phosphopeptides. In addition to the proximal effects on ABL and its immediate targets, dasatinib broadly affected the downstream MAPK pathways. Pathway mapping of regulated sites implicated a variety of cellular functions...

  18. Glycogen synthase kinase 3β sustains invasion of glioblastoma via the focal adhesion kinase, Rac1, and c-Jun N-terminal kinase-mediated pathway.

    Science.gov (United States)

    Chikano, Yuri; Domoto, Takahiro; Furuta, Takuya; Sabit, Hemragul; Kitano-Tamura, Ayako; Pyko, Ilya V; Takino, Takahisa; Sai, Yoshimichi; Hayashi, Yutaka; Sato, Hiroshi; Miyamoto, Ken-ichi; Nakada, Mitsutoshi; Minamoto, Toshinari

    2015-02-01

    The failure of current treatment options for glioblastoma stems from their inability to control tumor cell proliferation and invasion. Biologically targeted therapies offer great hope and one promising target is glycogen synthase kinase-3β (GSK3β), implicated in various diseases, including cancer. We previously reported that inhibition of GSK3β compromises the survival and proliferation of glioblastoma cells, induces their apoptosis, and sensitizes them to temozolomide and radiation. Here, we explore whether GSK3β also contributes to the highly invasive nature of glioblastoma. The effects of GSK3β inhibition on migration and invasion of glioblastoma cells were examined by wound-healing and Transwell assays, as well as in a mouse model of glioblastoma. We also investigated changes in cellular microarchitectures, cytoskeletal components, and proteins responsible for cell motility and invasion. Inhibition of GSK3β attenuated the migration and invasion of glioblastoma cells in vitro and that of tumor cells in a mouse model of glioblastoma. These effects were associated with suppression of the molecular axis involving focal adhesion kinase, guanine nucleotide exchange factors/Rac1 and c-Jun N-terminal kinase. Changes in cellular phenotypes responsible for cell motility and invasion were also observed, including decreased formation of lamellipodia and invadopodium-like microstructures and alterations in the subcellular localization, and activity of Rac1 and F-actin. These changes coincided with decreased expression of matrix metalloproteinases. Our results confirm the potential of GSK3β as an attractive therapeutic target against glioblastoma invasion, thus highlighting a second role in this tumor type in addition to its involvement in chemo- and radioresistance. PMID:25504636

  19. Review of current classification, molecular alterations, and tyrosine kinase inhibitor therapies in myeloproliferative disorders with hypereosinophilia

    Directory of Open Access Journals (Sweden)

    Havelange V

    2013-08-01

    Full Text Available Violaine Havelange,1,2 Jean-Baptiste Demoulin1 1de Duve Institute, Université catholique de Louvain, Brussels, Belgium; 2Department of Hematology, Cliniques universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium Abstract: Recent advances in our understanding of the molecular mechanisms underlying hypereosinophilia have led to the development of a 'molecular' classification of myeloproliferative disorders with eosinophilia. The revised 2008 World Health Organization classification of myeloid neoplasms included a new category called “myeloid and lymphoid neoplasms with eosinophilia and abnormalities of PDGFRA, PDGFRB or FGFR1.” Despite the molecular heterogeneity of PDGFR (platelet-derived growth factor receptor rearrangements, tyrosine kinase inhibitors at low dose induce rapid and complete hematological remission in the majority of these patients. Other kinase inhibitors are promising. Further discoveries of new molecular alterations will direct the development of new specific inhibitors. In this review, an update of the classifications of myeloproliferative disorders associated with hypereosinophilia is discussed together with open and controversial questions. Molecular mechanisms and promising results of tyrosine kinase inhibitor treatments are reviewed. Keywords: hypereosinophilia, classification, myeloproliferative disorders, molecular alterations, tyrosine kinase inhibitor

  20. [Dasatinib. A novel tyrosine kinase inhibitor for the treatment of chronic myeloid leukaemia

    DEFF Research Database (Denmark)

    Dufva, I.H.; Stentoft, J.; Hasselbalch, H.C.;

    2008-01-01

    Chronic myeloid leukaemia is characterized by an abnormal tyrosin kinase in the cytoplasm of the clonal cells. The enzyme is derived from a fusion gene on the Philadelphia-chromosome, evolved by a translocation between chromosomes 9 and 22. Understanding the biology of the tyrosin kinase led to t...... targeted therapy, inhibiting the ATP-binding site by a small molecule--imatinib (Glivec). A novel 2nd generation tyrosin kinase inhibitor--dasatinib (Sprycel)--is now available in cases of insufficient response or intolerance to imatinib Udgivelsesdato: 2008/1/28...

  1. Ibrutinib: a first in class covalent inhibitor of Bruton’s tyrosine kinase

    OpenAIRE

    Davids, Matthew S.; Brown, Jennifer R

    2014-01-01

    Ibrutinib (formerly PCI-32765) is a potent, covalent inhibitor of Bruton’s tyrosine kinase, a kinase downstream of the B-cell receptor that is critical for B-cell survival and proliferation. In preclinical studies, ibrutinib bound to Bruton’s tyrosine kinase with high affinity, leading to inhibition of B-cell receptor signaling, decreased B-cell activation and induction of apoptosis. In clinical studies, ibrutinib has been well-tolerated and has demonstrated profound anti-tumor activity in a ...

  2. Methods Of Using Chemical Libraries To Search For New Kinase Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Nathanael S. (Berkeley, CA), Schultz, Peter (Oakland, CA), Wodicka, Lisa (Santa Clara, CA), Meijer, Laurent (Roscoff, FR), Lockhart, David J. (Mountain View, CA)

    2003-06-03

    The generation of selective inhibitors for specific protein kinases would provide new tools for analyzing signal transduction pathways and possibly new therapeutic agents. We have invented an approach to the development of selective protein kinase inhibitors based on the unexpected binding mode of 2,6,9-trisubstituted purines to the ATP binding site of human CDK2. The most potent inhibitor, purvalanol B (IC.sub.50 =6 nM), binds with a 30-fold greater affinity than the known CDK2 inhibitor, flavopiridol. The cellular effects of this class of compounds were examined and compared to those of flavopiridol by monitoring changes in mRNA expression levels for all genes in treated cells of Saccharomyces cerevisiae using high-density oligonucleotide probe arrays.

  3. Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

    Directory of Open Access Journals (Sweden)

    Ohannessian Arthur

    2004-05-01

    Full Text Available Abstract Background Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK. Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK. Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC lines. Methods Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. Results In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. Conclusions We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway.

  4. PROLACTIN-INDUCED TYROSINE PHOSPHORYLATION, ACTIVATION AND RECEPTOR ASSOCIATION OF FOCAL ADHESION KINASE (FAK) IN MAMMARY EPITHELIAL CELLS

    Science.gov (United States)

    Prolactin-Induced Tyrosine Phosphorylation, Activation and ReceptorAssociation of Focal Adhesion Kinase (FAK) in Mammary Epithelial Cells. Suzanne E. Fenton1 and Lewis G. Sheffield2. 1U.S. Environmental ProtectionAgency, MD-72, Research Triangle Park, NC 27711, and

  5. Mammary gland-specific ablation of focal adhesion kinase reduces the incidence of p53-mediated mammary tumour formation.

    NARCIS (Netherlands)

    Miltenburg, van M.H.; Nimwegen, van M.J.; Tijdens, R.B.; Lalai, R.A.; Kuiper, R.; Klarenbeek, S.; Schouten, P.C.; Vries, de A.; Jonkers, J.M.M..; Water, van de B.

    2014-01-01

    BACKGROUND Elevated expression of focal adhesion kinase (FAK) occurs in numerous human cancers including colon-, cervix- and breast cancer. Although several studies have implicated FAK in mammary tumour formation induced by ectopic oncogene expression, evidence supporting a role for FAK in spontaneo

  6. Activation of cardiac chloride conductance by the tyrosine kinase inhibitor, genistein.

    OpenAIRE

    Shuba, L. M.; Asai, T.; Pelzer, S.; McDonald, T. F.

    1996-01-01

    1. Genistein (GST), an inhibitor of protein tyrosine kinase (PTK), Na3VO4 (VO4), an inhibitor of phosphotyrosine phosphatase (PTPase), and forskolin (FSK), an activator of the cyclic AMP-dependent, cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel, were applied to guinea-pig ventricular myocytes to probe for a possible role of tyrosine phosphorylation in the regulation of cardiac Cl- channels. 2. Myocytes in the standard whole-cell configuration were pulsed to various pot...

  7. Random Mutagenesis Reveals Residues of JAK2 Critical in Evading Inhibition by a Tyrosine Kinase Inhibitor

    OpenAIRE

    Marit, Michael R.; Chohan, Manprit; Matthew, Natasha; Huang, Kai; Kuntz, Douglas A.; Rose, David R.; Barber, Dwayne L.

    2012-01-01

    Background The non-receptor tyrosine kinase JAK2 is implicated in a group of myeloproliferative neoplasms including polycythemia vera, essential thrombocythemia, and primary myelofibrosis. JAK2-selective inhibitors are currently being evaluated in clinical trials. Data from drug-resistant chronic myeloid leukemia patients demonstrate that treatment with a small-molecule inhibitor generates resistance via mutation or amplification of BCR-ABL. We hypothesize that treatment with small molecule i...

  8. Bruton tyrosine kinase inhibitors: a promising novel targeted treatment for B cell lymphomas

    OpenAIRE

    Aalipour, Amin; Advani, Ranjana H.

    2013-01-01

    Constitutive or aberrant signalling of the B cell receptor signalling cascade has been implicated in the propagation and maintenance of a variety of B cell malignancies. Small molecule inhibitors of Bruton tyrosine kinase (BTK), a protein early in this cascade and specifically expressed in B cells, have emerged as a new class of targeted agents. There are several BTK inhibitors, including ONO-WG-307, LFM-A13, dasatinib, CC-292, and PCI-32765 (ibrutinib), in preclinical and/or clinical develop...

  9. Structural Mechanism of the Pan-BCR-ABL Inhibitor Ponatinib (AP24534): Lessons for Overcoming Kinase Inhibitor Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Tianjun; Commodore, Lois; Huang, Wei-Sheng; Wang, Yihan; Thomas, Mathew; Keats, Jeff; Xu, Qihong; Rivera, Victor M.; Shakespeare, William C.; Clackson, Tim; Dalgarno, David C.; Zhu, Xiaotian (ARIAD)

    2012-01-20

    The BCR-ABL inhibitor imatinib has revolutionized the treatment of chronic myeloid leukemia. However, drug resistance caused by kinase domain mutations has necessitated the development of new mutation-resistant inhibitors, most recently against the T315I gatekeeper residue mutation. Ponatinib (AP24534) inhibits both native and mutant BCR-ABL, including T315I, acting as a pan-BCR-ABL inhibitor. Here, we undertook a combined crystallographic and structure-activity relationship analysis on ponatinib to understand this unique profile. While the ethynyl linker is a key inhibitor functionality that interacts with the gatekeeper, virtually all other components of ponatinib play an essential role in its T315I inhibitory activity. The extensive network of optimized molecular contacts found in the DFG-out binding mode leads to high potency and renders binding less susceptible to disruption by single point mutations. The inhibitory mechanism exemplified by ponatinib may have broad relevance to designing inhibitors against other kinases with mutated gatekeeper residues.

  10. Focal adhesion kinase regulation in stem cell alignment and spreading on nanofibers.

    Science.gov (United States)

    Andalib, Mohammad Nahid; Lee, Jeong Soon; Ha, Ligyeom; Dzenis, Yuris; Lim, Jung Yul

    2016-05-13

    While electrospun nanofibers have demonstrated the potential for novel tissue engineering scaffolds, very little is known about the molecular mechanism of how cells sense and adapt to nanofibers. Here, we revealed the role of focal adhesion kinase (FAK), one of the key molecular sensors in the focal adhesion complex, in regulating mesenchymal stem cell (MSC) shaping on nanofibers. We produced uniaxially aligned and randomly distributed nanofibers from poly(l-lactic acid) to have the same diameters (about 130 nm) and evaluated MSC behavior on these nanofibers comparing with that on flat PLLA control. C3H10T1/2 murine MSCs exhibited upregulations in FAK expression and phosphorylation (pY397) on nanofibrous cultures as assessed by immunoblotting, and this trend was even greater on aligned nanofibers. MSCs showed significantly elongated and well-spread morphologies on aligned and random nanofibers, respectively. In the presence of FAK silencing via small hairpin RNA (shRNA), cell elongation length in the aligned nanofiber direction (cell major axis length) was significantly decreased, while cells still showed preferred orientation along the aligned nanofibers. On random nanofibers, MSCs with FAK-shRNA showed impaired cell spreading resulting in smaller cell area and higher circularity. Our study provides new data on how MSCs shape their morphologies on aligned and random nanofibrous cultures potentially via FAK-mediated mechanism. PMID:27040763

  11. Cytoskeletal inhibitors, anti-adhesion molecule antibodies, and lectins inhibit hepatocyte spheroid formation.

    Directory of Open Access Journals (Sweden)

    Nakamura M

    2002-02-01

    Full Text Available We investigated the role of cytoskeletons, adhesion molecules, membrane-glycosylations, and proteoglycans in forming the shape of adult rat hepatocyte spheroids. Isolated hepatocytes were cultured on dishes coated with chondroitin sulfate phosphatidyl ethanolamine (CS-PE. Spheroid-forming ability was observed after adding cytoskeletal inhibitors (cytochalasin D, colchicine, okadaic acid, mycalolide B, anti-adhesion molecule antibodies (anti-E-cadherin, anti-connexin 32, anti-zo-1, a glycosphingolipid synthetic inhibitor (N-butyldeoxynojirimycin, a proteoglycan synthetic inhibitor (p-nitrophenyl-beta-D-xylopyranoside, and several lectins. Localization of actin was studied using confocal microscopy after rhodamine-phalloidin staining. Adding cytoskeletal inhibitors on the initial day resulted in weakly clustered cell aggregates rather than smoothly formed spheroids. These effects disappeared at lower reagent concentrations. When reagents were added on day 3, after the formation of spheroids, only mycalolide B was associated with an irregular spheroid surface; the others had no effect. Adding the anti-E-cadherin, anti-connexin 32 on the initial day showed inhibition of spheroid formation, but anti-zo-1 and proteoglycan synthetic inhibitor had no effects. Among the several lectins, only Wheat Germ Agglutinin (WGA, Ricinus communis Agglutinin I (RCA-I, and Concanavalin A (ConA showed inhibition. These results suggest that cytoskeletal conformation and some adhesion molecules are necessary to form spheroids. Based on the interactions between lectins and hepatocytes in the present study, hepatocytes appear to contain an N-linked complex or N-linked hybrid glycosylated chains.

  12. Non-small-cell lung cancer cells combat epidermal growth factor receptor tyrosine kinase inhibition through immediate adhesion-related responses

    Directory of Open Access Journals (Sweden)

    Wang HY

    2016-05-01

    Full Text Available Hsian-Yu Wang,1,2 Min-Kung Hsu,3,4 Kai-Hsuan Wang,1 Ching-Ping Tseng,2,4 Feng-Chi Chen,3,4 John T-A Hsu1,4 1Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes (NHRI, Zhunan, Miaoli County, 2Institute of Molecular Medicine and Bioengineering, National Chiao Tung University (NCTU, Hsinchu, 3Division of Biostatistics and Bioinformatics, Institute of Population Health Sciences, National Health Research Institutes (NHRI, Zhunan, Miaoli County, 4Department of Biological Science and Technology, National Chiao Tung University (NCTU, Hsinchu, Taiwan, Republic of China Background: Epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKIs, such as gefitinib, erlotinib, and afatinib, have greatly improved treatment efficacy in non-small cell lung cancer (NSCLC patients with drug-sensitive EGFR mutations. However, in some TKI responders, the benefits of such targeted therapies are limited by the rapid development of resistance, and strategies to overcome this resistance are urgently needed. Studies of drug resistance in cancer cells typically involve long term in vitro induction to obtain stably acquired drug-resistant cells followed by elucidation of resistance mechanisms, but the immediate responses of cancer cells upon drug treatment have been ignored. The aim of this study was to investigate the immediate responses of NSCLC cells upon treatment with EGFR TKIs.Results: Both NSCLC cells, ie, PC9 and H1975, showed immediate enhanced adhesion-related responses as an apoptosis-countering mechanism upon first-time TKI treatment. By gene expression and pathway analysis, adhesion-related pathways were enriched in gefitinib-treated PC9 cells. Pathway inhibition by small-hairpin RNAs or small-molecule drugs revealed that within hours of EGFR TKI treatment, NSCLC cells used adhesion-related responses to combat the drugs. Importantly, we show here that the Src family inhibitor, dasatinib, dramatically inhibits

  13. Discovery and Characterization of Non-ATP Site Inhibitors of the Mitogen Activated Protein (MAP) Kinases

    Energy Technology Data Exchange (ETDEWEB)

    Comess, Kenneth M.; Sun, Chaohong; Abad-Zapatero, Cele; Goedken, Eric R.; Gum, Rebecca J.; Borhani, David W.; Argiriadi, Maria; Groebe, Duncan R.; Jia, Yong; Clampit, Jill E.; Haasch, Deanna L.; Smith, Harriet T.; Wang, Sanyi; Song, Danying; Coen, Michael L.; Cloutier, Timothy E.; Tang, Hua; Cheng, Xueheng; Quinn, Christopher; Liu, Bo; Xin, Zhili; Liu, Gang; Fry, Elizabeth H.; Stoll, Vincent; Ng, Teresa I.; Banach, David; Marcotte, Doug; Burns, David J.; Calderwood, David J.; Hajduk, Philip J. (Abbott)

    2012-03-02

    Inhibition of protein kinases has validated therapeutic utility for cancer, with at least seven kinase inhibitor drugs on the market. Protein kinase inhibition also has significant potential for a variety of other diseases, including diabetes, pain, cognition, and chronic inflammatory and immunologic diseases. However, as the vast majority of current approaches to kinase inhibition target the highly conserved ATP-binding site, the use of kinase inhibitors in treating nononcology diseases may require great selectivity for the target kinase. As protein kinases are signal transducers that are involved in binding to a variety of other proteins, targeting alternative, less conserved sites on the protein may provide an avenue for greater selectivity. Here we report an affinity-based, high-throughput screening technique that allows nonbiased interrogation of small molecule libraries for binding to all exposed sites on a protein surface. This approach was used to screen both the c-Jun N-terminal protein kinase Jnk-1 (involved in insulin signaling) and p38{alpha} (involved in the formation of TNF{alpha} and other cytokines). In addition to canonical ATP-site ligands, compounds were identified that bind to novel allosteric sites. The nature, biological relevance, and mode of binding of these ligands were extensively characterized using two-dimensional {sup 1}H/{sup 13}C NMR spectroscopy, protein X-ray crystallography, surface plasmon resonance, and direct enzymatic activity and activation cascade assays. Jnk-1 and p38{alpha} both belong to the MAP kinase family, and the allosteric ligands for both targets bind similarly on a ledge of the protein surface exposed by the MAP insertion present in the CMGC family of protein kinases and distant from the active site. Medicinal chemistry studies resulted in an improved Jnk-1 ligand able to increase adiponectin secretion in human adipocytes and increase insulin-induced protein kinase PKB phosphorylation in human hepatocytes, in

  14. Protein kinase inhibitors CK59 and CID755673 alter primary human NK cell effector functions

    Directory of Open Access Journals (Sweden)

    Maxi eScheiter

    2013-03-01

    Full Text Available Natural killer (NK cells are part of the innate immune response and play a crucial role in the defense against tumors and virus-infected cells. Their effector functions include the specific killing of target cells, as well as the modulation of other immune cells by cytokine release. Kinases constitute a relevant part in signaling, are prime targets in drug research and the protein kinase inhibitor Dasatinib is already used for immune-modulatory theraphies. In this study, we have tested the effects of the kinase inhibitors CK59 and CID755673. These inhibitors are directed against CaMKII (CK59 and PKD family kinases (CID755673 that were previously suggested as novel components of NK activation pathways. Here, we use a multi-parameter, FACS-based assay to validate the influence of CK59 and CID755673 on the effector functions of primary NK cells. Dose dependent treatment with CK59 and CID755673 indeed results in a significant reduction of NK cell degranulation markers and cytokine release in freshly isolated PBMC populations from healthy blood donors. These results underline the importance of CaMKII for NK cell signaling and suggest PKD2 as a novel signaling component in NK cell activation. Notably, kinase inhibition studies on pure NK cell populations indicate significant donor variations.

  15. The tyrosine kinase inhibitor sunitinib affects ovulation but not ovarian reserve in mouse: A preclinical study

    NARCIS (Netherlands)

    V. Bernard (Valérie); J. Bouilly (Justine); P. Kramer (Piet); N. Carré (Nadège); M. Schlumberger (Martin); J.A. Visser (Jenny A.); J. Young (Jacques); N.B. Binart (Nadine Binart)

    2016-01-01

    textabstractThe aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI) sunitinib, since only scarce data are available on gonadal function after this treatment. Six-weekold female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d) during 5 weeks. Fertil

  16. A comparison of protein kinases inhibitor screening methods using both enzymatic activity and binding affinity determination

    DEFF Research Database (Denmark)

    Rudolf, Amalie Frederikke; Skovgaard, Tine; Knapp, Stefan;

    2014-01-01

    Binding assays are increasingly used as a screening method for protein kinase inhibitors; however, as yet only a weak correlation with enzymatic activity-based assays has been demonstrated. We show that the correlation between the two types of assays can be improved using more precise screening...

  17. Receptor-Based Virtual Screening of EGFR Kinase Inhibitors from the NCI Diversity Database

    Directory of Open Access Journals (Sweden)

    Kiattawee Choowongkomon

    2010-06-01

    Full Text Available Epidermal growth factor receptor (EGFR abnormalities have been associated with several types of human cancer. The crystal structures of its tyrosine kinase domain (EGFR-TK complexed with small molecule inhibitors revealed the kinase inhibition modes, prompting us to search for novel anti-cancer drugs. A total of 1,990 compounds from the National Cancer Institute (NCI diversity set with nonredundant structures have been tested to inhibit cancer cell lines with unknown mechanism. Cancer inhibition through EGFR-TK is one of the mechanisms of these compounds. In this work, we performed receptor-based virtual screening against the NCI diversity database. Using two different docking algorithms, AutoDock and Gold, combined with subsequent post-docking analyses, we found eight candidate compounds with high scoring functions that all bind to the ATP-competitive site of the kinase. None of these compounds belongs to the main group of the currently known EGFR-TK inhibitors. Binding mode analyses revealed that the way these compounds complexed with EGFR-TK differs from quinazoline inhibitor binding and the interaction mainly involves hydrophobic interactions. Also, the common kinase-inhibitor (NH---N and CO---HC hydrogen bonds between the hinge region and the hit compounds are rarely observed. Our results suggest that these molecules could be developed as novel lead compounds in anti-cancer drug design.

  18. Synthesis of Benzofuran Analogue of Go6976, an Isoform Selective Protein Kinase C Inhibitor

    Institute of Scientific and Technical Information of China (English)

    MA, Da-Wei; ZHANG, Xin-Rong; WU, Shi-Hui; TAO, Feng-Gang

    2001-01-01

    Based on the structure of Go6976, a known isoform-selective protein kinase C inhibitor, a benzofuran analogue (1) was designed. This analogue was synthesized by coupling of benzofuran 3-acetic acid and 8-oxo-tryptamine and subsequent intramolecular Dieckmann condensation, alkylation, oxidative photocyclization and cyanation reaction of mesylate.

  19. Crystal structure of the PIM2 kinase in complex with an organoruthenium inhibitor.

    Directory of Open Access Journals (Sweden)

    Alex N Bullock

    Full Text Available BACKGROUND: The serine/threonine kinase PIM2 is highly expressed in human leukemia and lymphomas and has been shown to positively regulate survival and proliferation of tumor cells. Its diverse ATP site makes PIM2 a promising target for the development of anticancer agents. To date our knowledge of catalytic domain structures of the PIM kinase family is limited to PIM1 which has been extensively studied and which shares about 50% sequence identity with PIM2. PRINCIPAL FINDINGS: Here we determined the crystal structure of PIM2 in complex with an organoruthenium complex (inhibition in sub-nanomolar level. Due to its extraordinary shape complementarity this stable organometallic compound is a highly potent inhibitor of PIM kinases. SIGNIFICANCE: The structure of PIM2 revealed several differences to PIM1 which may be explored further to generate isoform selective inhibitors. It has also demonstrated how an organometallic inhibitor can be adapted to the binding site of protein kinases to generate highly potent inhibitors. ENHANCED VERSION: This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  20. Inhibitors of Glycogen Synthase Kinase 3 with Exquisite Kinome-Wide Selectivity and Their Functional Effects.

    Science.gov (United States)

    Wagner, Florence F; Bishop, Joshua A; Gale, Jennifer P; Shi, Xi; Walk, Michelle; Ketterman, Joshua; Patnaik, Debasis; Barker, Doug; Walpita, Deepika; Campbell, Arthur J; Nguyen, Shannon; Lewis, Michael; Ross, Linda; Weïwer, Michel; An, W Frank; Germain, Andrew R; Nag, Partha P; Metkar, Shailesh; Kaya, Taner; Dandapani, Sivaraman; Olson, David E; Barbe, Anne-Laure; Lazzaro, Fanny; Sacher, Joshua R; Cheah, Jaime H; Fei, David; Perez, Jose; Munoz, Benito; Palmer, Michelle; Stegmaier, Kimberly; Schreiber, Stuart L; Scolnick, Edward; Zhang, Yan-Ling; Haggarty, Stephen J; Holson, Edward B; Pan, Jen Q

    2016-07-15

    The mood stabilizer lithium, the first-line treatment for bipolar disorder, is hypothesized to exert its effects through direct inhibition of glycogen synthase kinase 3 (GSK3) and indirectly by increasing GSK3's inhibitory serine phosphorylation. GSK3 comprises two highly similar paralogs, GSK3α and GSK3β, which are key regulatory kinases in the canonical Wnt pathway. GSK3 stands as a nodal target within this pathway and is an attractive therapeutic target for multiple indications. Despite being an active field of research for the past 20 years, many GSK3 inhibitors demonstrate either poor to moderate selectivity versus the broader human kinome or physicochemical properties unsuitable for use in in vitro systems or in vivo models. A nonconventional analysis of data from a GSK3β inhibitor high-throughput screening campaign, which excluded known GSK3 inhibitor chemotypes, led to the discovery of a novel pyrazolo-tetrahydroquinolinone scaffold with unparalleled kinome-wide selectivity for the GSK3 kinases. Taking advantage of an uncommon tridentate interaction with the hinge region of GSK3, we developed highly selective and potent GSK3 inhibitors, BRD1652 and BRD0209, which demonstrated in vivo efficacy in a dopaminergic signaling paradigm modeling mood-related disorders. These new chemical probes open the way for exclusive analyses of the function of GSK3 kinases in multiple signaling pathways involved in many prevalent disorders. PMID:27128528

  1. Design of Targeted Inhibitors of Polo-like Kinase 1 (Plk1)

    Science.gov (United States)

    Dalafave, D. S.

    2011-03-01

    Computational design of small molecule inhibitors of Polo-like Kinase 1 (Plk1) is presented. Plk1, which regulates cell cycle, is often overexpressed in cancers. Its downregulation was shown to inhibit cancer progression. Most inhibitors of kinases' interact with the highly conserved ATP binding site. This makes the development of Plk1-specific inhibitors challenging, since different kinases have similar ATP sites. However, Plk1 also contains the polo-box domain (PBD), which is absent from other kinases. In this study, the PBD site was used as a target for designed Plk1 inhibitors. Common structural features of experimentally known Plk1 ligands were first identified. The information was used to design putative small molecules that specifically bonded Plk1. Druglikeness and possible toxicities of the designed molecules were determined. Molecules with no implied toxicities and optimal druglikeness were used for docking studies. The docking studies identified several molecules that made stable complexes with the Plk1 PBD site. Possible utilization of the designed molecules in drugs against cancers with overexpressed Plk1 is discussed.

  2. Protein kinase C-δ inhibitor, Rottlerin inhibits growth and survival of mycobacteria exclusively through Shikimate kinase.

    Science.gov (United States)

    Pandey, Sapna; Chatterjee, Aditi; Jaiswal, Swati; Kumar, Sanjay; Ramachandran, Ravishankar; Srivastava, Kishore K

    2016-09-16

    The molecular bases of disease provide exceptional prospect to translate research findings into new drugs. Nevertheless, to develop new and novel chemical entities takes huge amount of time and efforts, mainly due to the stringent processes. Therefore, drug repurposing is one of such strategies which is being used in recent times to identify new pharmacophores. The essential first step in discovery of the specific inhibitor with low toxicity is the identification and elucidation of pathways exclusive to target pathogen. One such target is the shikimate pathway, which is essential for algae, higher plants, bacteria and fungi. Since, this enzyme system is absent in higher eukaryotes and in mammals, the enzymes involved in the pathway provide an attractive target for the development of potentially selective and non toxic antimicrobial agents. Since, so far there is no specific inhibitor which is able to restrain mycobacterial shikimate pathway; we expanded the use of a known kinase inhibitor; Rottlerin, in order to predict the prototype in discovering the specific molecules against this enzyme. For the first time we have shown that Rottlerin inhibits extracellular mycobacteria by affecting Shikimate Kinase (SK) and this effect is further enhanced during the intracellular infection due to the added effect of PKC- δ down-regulation. The molecular docking of Rottlerin with both the mycobacterial SKs, corroborated the inhibition data, and revealed that the effects of SK, in slow and in fast grower mycobacteria are due to the changes in affinity of binding with the drug. PMID:27498028

  3. A Small-Molecule Inhibitor of PIM Kinases as a Potential Treatment for Urothelial Carcinomas

    Directory of Open Access Journals (Sweden)

    Jason M. Foulks

    2014-05-01

    Full Text Available The proto-oncogene proviral integration site for moloney murine leukemia virus (PIM kinases (PIM-1, PIM-2, and PIM-3 are serine/threonine kinases that are involved in a number of signaling pathways important to cancer cells. PIM kinases act in downstream effector functions as inhibitors of apoptosis and as positive regulators of G1-S phase progression through the cell cycle. PIM kinases are upregulated in multiple cancer indications, including lymphoma, leukemia, multiple myeloma, and prostate, gastric, and head and neck cancers. Overexpression of one or more PIM family members in patient tumors frequently correlates with poor prognosis. The aim of this investigation was to evaluate PIM expression in low- and high-grade urothelial carcinoma and to assess the role PIM function in disease progression and their potential to serve as molecular targets for therapy. One hundred thirty-seven cases of urothelial carcinoma were included in this study of surgical biopsy and resection specimens. High levels of expression of all three PIM family members were observed in both noninvasive and invasive urothelial carcinomas. The second-generation PIM inhibitor, TP-3654, displays submicromolar activity in pharmacodynamic biomarker modulation, cell proliferation studies, and colony formation assays using the UM-UC-3 bladder cancer cell line. TP-3654 displays favorable human ether-à-go-go-related gene and cytochrome P450 inhibition profiles compared with the first-generation PIM inhibitor, SGI-1776, and exhibits oral bioavailability. In vivo xenograft studies using a bladder cancer cell line show that PIM kinase inhibition can reduce tumor growth, suggesting that PIM kinase inhibitors may be active in human urothelial carcinomas.

  4. QSAR, molecular docking studies of thiophene and imidazopyridine derivatives as polo-like kinase 1 inhibitors

    Science.gov (United States)

    Cao, Shandong

    2012-08-01

    The purpose of the present study was to develop in silico models allowing for a reliable prediction of polo-like kinase inhibitors based on a large diverse dataset of 136 compounds. As an effective method, quantitative structure activity relationship (QSAR) was applied using the comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). The proposed QSAR models showed reasonable predictivity of thiophene analogs (Rcv2=0.533, Rpred2=0.845) and included four molecular descriptors, namely IC3, RDF075m, Mor02m and R4e+. The optimal model for imidazopyridine derivatives (Rcv2=0.776, Rpred2=0.876) was shown to perform good in prediction accuracy, using GATS2m and BEHe1 descriptors. Analysis of the contour maps helped to identify structural requirements for the inhibitors and served as a basis for the design of the next generation of the inhibitor analogues. Docking studies were also employed to position the inhibitors into the polo-like kinase active site to determine the most probable binding mode. These studies may help to understand the factors influencing the binding affinity of chemicals and to develop alternative methods for prescreening and designing of polo-like kinase inhibitors.

  5. A targeted library screen reveals a new inhibitor scaffold for protein kinase D.

    Directory of Open Access Journals (Sweden)

    Manuj Tandon

    Full Text Available Protein kinase D (PKD has emerged as a potential therapeutic target in multiple pathological conditions, including cancer and heart diseases. Potent and selective small molecule inhibitors of PKD are valuable for dissecting PKD-mediated cellular signaling pathways and for therapeutic application. In this study, we evaluated a targeted library of 235 small organic kinase inhibitors for PKD1 inhibitory activity at a single concentration. Twenty-eight PKD inhibitory chemotypes were identified and six exhibited excellent PKD1 selectivity. Five of the six lead structures share a common scaffold, with compound 139 being the most potent and selective for PKD vs PKC and CAMK. Compound 139 was an ATP-competitive PKD1 inhibitor with a low double-digit nanomolar potency and was also cell-active. Kinase profiling analysis identified this class of small molecules as pan-PKD inhibitors, confirmed their selectivity again PKC and CAMK, and demonstrated an overall favorable selectivity profile that could be further enhanced through structural modification. Furthermore, using a PKD homology model based on similar protein kinase structures, docking modes for compound 139 were explored and compared to literature examples of PKD inhibition. Modeling of these compounds at the ATP-binding site of PKD was used to rationalize its high potency and provide the foundation for future further optimization. Accordingly, using biochemical screening of a small number of privileged scaffolds and computational modeling, we have identified a new core structure for highly potent PKD inhibition with promising selectivity against closely related kinases. These lead structures represent an excellent starting point for the further optimization and the design of selective and therapeutically effective small molecule inhibitors of PKD.

  6. Focal adhesion kinase and Src phosphorylations in HGF-induced proliferation and invasion of human cholangiocarcinoma cell line, HuCCA-1

    Institute of Scientific and Technical Information of China (English)

    Urai Pongchairerk; Jun-Lin Guan; Vijittra Leardkamolkarn

    2005-01-01

    AIM: To study the role of focal adhesion kinase (FAK) and its association with Src in hepatocyte growth factor (HGF)-induced cell signaling in cholangiocarcinoma progression.METHODS: Previously isolated HuCCA-1 cells were re-characterized by immunofluorescent staining and reverse transcriptase-polymerase chain reaction assay for the expression of cytokeratin 19, HGF and c-Met mRNA. Cultured HuCCA-1 cells were treated with HGF and determined for cell proliferation and invasion effects by MTT and invasion assays. Western blotting, immunoprecipitation, and co-immunoprecipitation were also performed to study the phosphorylation and interaction of FAK and Src. A novel Src inhibitor (AZM555130) was applied in cultures to investigate the effects on FAK phosphorylation inhibition and on cell proliferation and invasion.RESULTS: HGF enhanced HuCCA-1 cell proliferation and invasion by mediating FAK and Src phosphorylations.FAK-Src interaction occurred in a time-dependent manner that Src was proved to be an upstream signaling molecule to FAK. The inhibitor to Src decreased FAK phosphorylation level in correlation with the reduction of cell proliferation and invasion.CONCLUSION: FAK plays a significant role in signaling pathway of HGF-responsive cell line derived from cholangiocarcinoma. Autophosphorylated Src, induced by HGF, mediates Src kinase activation, which subsequently phosphorylates its substrate, FAK, and signals to cell proliferation and invasion.

  7. Molecular characterization of c-Abl/c-Src kinase inhibitors targeted against murine tumour progenitor cells that express stem cell markers.

    Directory of Open Access Journals (Sweden)

    Thomas Kruewel

    Full Text Available BACKGROUND: The non-receptor tyrosine kinases c-Abl and c-Src are overexpressed in various solid human tumours. Inhibition of their hyperactivity represents a molecular rationale in the combat of cancerous diseases. Here we examined the effects of a new family of pyrazolo [3,4-d] pyrimidines on a panel of 11 different murine lung tumour progenitor cell lines, that express stem cell markers, as well as on the human lung adenocarcinoma cell line A549, the human hepatoma cell line HepG2 and the human colon cancer cell line CaCo2 to obtain insight into the mode of action of these experimental drugs. METHODOLOGY/PRINCIPAL FINDINGS: Treatment with the dual kinase inhibitors blocked c-Abl and c-Src kinase activity efficiently in the nanomolar range, induced apoptosis, reduced cell viability and caused cell cycle arrest predominantly at G0/G1 phase while western blot analysis confirmed repressed protein expression of c-Abl and c-Src as well as the interacting partners p38 mitogen activated protein kinase, heterogenous ribonucleoprotein K, cyclin dependent kinase 1 and further proteins that are crucial for tumour progression. Importantly, a significant repression of the epidermal growth factor receptor was observed while whole genome gene expression analysis evidenced regulation of many cell cycle regulated genes as well integrin and focal adhesion kinase (FAK signalling to impact cytoskeleton dynamics, migration, invasion and metastasis. CONCLUSIONS/SIGNIFICANCE: Our experiments and recently published in vivo engraftment studies with various tumour cell lines revealed the dual kinase inhibitors to be efficient in their antitumour activity.

  8. Key Structures and Interactions for Binding of Mycobacterium tuberculosis Protein Kinase B Inhibitors from Molecular Dynamics Simulation.

    Science.gov (United States)

    Punkvang, Auradee; Kamsri, Pharit; Saparpakorn, Patchreenart; Hannongbua, Supa; Wolschann, Peter; Irle, Stephan; Pungpo, Pornpan

    2015-07-01

    Substituted aminopyrimidine inhibitors have recently been introduced as antituberculosis agents. These inhibitors show impressive activity against protein kinase B, a Ser/Thr protein kinase that is essential for cell growth of M. tuberculosis. However, up to now, X-ray structures of the protein kinase B enzyme complexes with the substituted aminopyrimidine inhibitors are currently unavailable. Consequently, structural details of their binding modes are questionable, prohibiting the structural-based design of more potent protein kinase B inhibitors in the future. Here, molecular dynamics simulations, in conjunction with molecular mechanics/Poisson-Boltzmann surface area binding free-energy analysis, were employed to gain insight into the complex structures of the protein kinase B inhibitors and their binding energetics. The complex structures obtained by the molecular dynamics simulations show binding free energies in good agreement with experiment. The detailed analysis of molecular dynamics results shows that Glu93, Val95, and Leu17 are key residues responsible to the binding of the protein kinase B inhibitors. The aminopyrazole group and the pyrimidine core are the crucial moieties of substituted aminopyrimidine inhibitors for interaction with the key residues. Our results provide a structural concept that can be used as a guide for the future design of protein kinase B inhibitors with highly increased antagonistic activity.

  9. 3-Phosphoinositide-Dependent protein Kinase-1 (PDK1) inhibitors: A review from patent literature

    Science.gov (United States)

    Barile, Elisa; De, Surya K.; Pellecchia, Maurizio

    2016-01-01

    PDK1 (3-Phosphoinositide-dependent kinase 1) is a key member of the AGC protein kinase family. It plays an important role in a variety of cellular functions, leading to the activation of the PI3K signaling pathway, an event often associated with the onset and progression of several human cancers. Numerous recent observations suggest that PDK1 inhibitors may provide novel opportunities for the development of effective classes of therapeutics. On these premises, recent years have witnessed an increased effort by medicinal chemists to develop novel scaffolds to derive potent and selective PDK1 inhibitors. The intent of this review is to update the reader on the recent patent literature covering applications published between June 2008 and September 2011 that report on PDK1 inhibitors. PMID:24236780

  10. Sonic hedgehog regulates osteoblast function by focal adhesion kinase signaling in the process of fracture healing.

    Directory of Open Access Journals (Sweden)

    Yuu Horikiri

    Full Text Available Several biological studies have indicated that hedgehog signaling plays an important role in osteoblast proliferation and differentiation, and sonic hedgehog (SHH expression is positively correlated with phosphorylated focal adhesion kinase (FAK Tyr(397. However, the relationship between them and their role in the process of normal fracture repair has not been clarified yet. Immunohistochemical analysis revealed that SHH and pFAK Tyr(397 were expressed in bone marrow cells and that pFAK Tyr(397 was also detected in ALP-positive osteoblasts near the TRAP-positive osteoclasts in the fracture site in the ribs of mice on day 5 after fracture. SHH and pFAK Tyr(397 were detectable in osteoblasts near the hypertrophic chondrocytes on day 14. In vitro analysis showed that SHH up-regulated the expression of FAK mRNA and pFAK Tyr(397 time dependently in osteoblastic MC3T3-E1 cells. Functional analysis revealed that 5 lentivirus encoding short hairpin FAK RNAs (shFAK-infected MC3T3-E1 cell groups displayed a round morphology and decreased proliferation, adhesion, migration, and differentiation. SHH stimulated the proliferation and differentiation of MC3T3-E1 cells, but had no effect on the shFAK-infected cells. SHH also stimulated osteoclast formation in a co-culture system containing MC3T3-E1 and murine CD11b(+ bone marrow cells, but did not affect the shFAK-infected MC3T3-E1 co-culture group. These data suggest that SHH signaling was activated in osteoblasts at the dynamic remodeling site of a bone fracture and regulated their proliferation and differentiation, as well as osteoclast formation, via FAK signaling.

  11. Kinase Inhibitors that Increase the Sensitivity of Methicillin Resistant Staphylococcus aureus to β-Lactam Antibiotics

    Directory of Open Access Journals (Sweden)

    Jay Vornhagen

    2015-10-01

    Full Text Available Staphylococcus aureus are Gram-positive bacteria that are the leading cause of recurrent infections in humans that include pneumonia, bacteremia, osteomyelitis, arthritis, endocarditis, and toxic shock syndrome. The emergence of methicillin resistant S. aureus strains (MRSA has imposed a significant concern in sustained measures of treatment against these infections. Recently, MRSA strains deficient in expression of a serine/threonine kinase (Stk1 or PknB were described to exhibit increased sensitivity to β-lactam antibiotics. In this study, we screened a library consisting of 280 drug-like, low-molecular-weight compounds with the ability to inhibit protein kinases for those that increased the sensitivity of wild-type MRSA to β-lactams and then evaluated their toxicity in mice. We report the identification of four kinase inhibitors, the sulfonamides ST085384, ST085404, ST085405, and ST085399 that increased sensitivity of WT MRSA to sub-lethal concentrations of β-lactams. Furthermore, these inhibitors lacked alerting structures commonly associated with toxic effects, and toxicity was not observed with ST085384 or ST085405 in vivo in a murine model. These results suggest that kinase inhibitors may be useful in therapeutic strategies against MRSA infections.

  12. Identification and Structure-Function Analysis of Subfamily Selective G Protein-Coupled Receptor Kinase Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Homan, Kristoff T.; Larimore, Kelly M.; Elkins, Jonathan M.; Szklarz, Marta; Knapp, Stefan; Tesmer, John J.G. [Michigan; (Oxford)

    2015-02-13

    Selective inhibitors of individual subfamilies of G protein-coupled receptor kinases (GRKs) would serve as useful chemical probes as well as leads for therapeutic applications ranging from heart failure to Parkinson’s disease. To identify such inhibitors, differential scanning fluorimetry was used to screen a collection of known protein kinase inhibitors that could increase the melting points of the two most ubiquitously expressed GRKs: GRK2 and GRK5. Enzymatic assays on 14 of the most stabilizing hits revealed that three exhibit nanomolar potency of inhibition for individual GRKs, some of which exhibiting orders of magnitude selectivity. Most of the identified compounds can be clustered into two chemical classes: indazole/dihydropyrimidine-containing compounds that are selective for GRK2 and pyrrolopyrimidine-containing compounds that potently inhibit GRK1 and GRK5 but with more modest selectivity. The two most potent inhibitors representing each class, GSK180736A and GSK2163632A, were cocrystallized with GRK2 and GRK1, and their atomic structures were determined to 2.6 and 1.85 Å spacings, respectively. GSK180736A, developed as a Rho-associated, coiled-coil-containing protein kinase inhibitor, binds to GRK2 in a manner analogous to that of paroxetine, whereas GSK2163632A, developed as an insulin-like growth factor 1 receptor inhibitor, occupies a novel region of the GRK active site cleft that could likely be exploited to achieve more selectivity. However, neither compound inhibits GRKs more potently than their initial targets. This data provides the foundation for future efforts to rationally design even more potent and selective GRK inhibitors.

  13. Combining the pan-aurora kinase inhibitor AMG 900 with histone deacetylase inhibitors enhances antitumor activity in prostate cancer

    International Nuclear Information System (INIS)

    Histone deacetylase inhibitors (HDACIs) are being tested in clinical trials for the treatment of solid tumors. While most studies have focused on the reexpression of silenced tumor suppressor genes, a number of genes/pathways are downregulated by HDACIs. This provides opportunities for combination therapy: agents that further disable these pathways through inhibition of residual gene function are speculated to enhance cell death in combination with HDACIs. A previous study from our group indicated that mitotic checkpoint kinases such as PLK1 and Aurora A are downregulated by HDACIs. We used in vitro and in vivo xenograft models of prostate cancer (PCA) to test whether combination of HDACIs with the pan-aurora kinase inhibitor AMG 900 can synergistically or additively kill PCA cells. AMG 900 and HDACIs synergistically decreased cell proliferation activity and clonogenic survival in DU-145, LNCaP, and PC3 PCA cell lines compared to single-agent treatment. Cellular senescence, polyploidy, and apoptosis was significantly increased in all cell lines after combination treatment. In vivo xenograft studies indicated decreased tumor growth and decreased aurora B kinase activity in mice treated with low-dose AMG 900 and vorinostat compared to either agent alone. Pharmacodynamics was assessed by scoring for phosphorylated histone H3 through immunofluorescence. Our results indicate that combination treatment with low doses of AMG 900 and HDACIs could be a promising therapy for future clinical trials against PCA

  14. Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Okabe, Seiichi, E-mail: okabe@tokyo-med.ac.jp; Tauchi, Tetsuzo; Tanaka, Yuko; Ohyashiki, Kazuma

    2013-06-07

    Highlights: •Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells okabe et al. •Imatinib or nilotinib resistance was involved Src family kinase. •The BCR-ABL point mutation (E334V) was highly resistant to imatinib or nilotinib. •Ponatinib was a powerful strategy against imatinib or nilotinib resistant Ph-positive cells. -- Abstract: Because a substantial number of patients with chronic myeloid leukemia acquire resistance to ABL tyrosine kinase inhibitors (TKIs), their management remains a challenge. Ponatinib, also known as AP24534, is an oral multi-targeted TKI. Ponatinib is currently being investigated in a pivotal phase 2 clinical trial. In the present study, we analyzed the molecular and functional consequences of ponatinib against imatinib- or nilotinib-resistant (R) K562 and Ba/F3 cells. The proliferation of imatinib- or nilotinib-resistant K562 cells did not decrease after treatment with imatinib or nilotinib. Src family kinase Lyn was activated. Point mutation Ba/F3 cells (E334 V) were also highly resistant to imatinib and nilotinib. Treatment with ponatinib for 72 h inhibited the growth of imatinib- and nilotinib-resistant cells. The phosphorylation of BCR-ABL, Lyn, and Crk-L was reduced. This study demonstrates that ponatinib has an anti-leukemia effect by reducing ABL and Lyn kinase activity and this information may be of therapeutic relevance.

  15. Comparative VEGF receptor tyrosine kinase modeling for the development of highly specific inhibitors of tumor angiogenesis.

    Science.gov (United States)

    Schmidt, Ulrike; Ahmed, Jessica; Michalsky, Elke; Hoepfner, Michael; Preissner, Robert

    2008-01-01

    The Vascular Endothelial Growth Factor receptors (VEGF-Rs) play a significant role in tumor development and tumor angiogenesis and are therefore interesting targets in cancer therapy. Targeting the VEGF-R is of special importance as the feed of the tumor has to be reduced. In general, this can be carried out by inhibiting the tyrosine kinase function of the VEGF-R. Nevertheless, there arise some problems with the specificity of known kinase inhibitors: they bind to the ATP-binding site and inhibit a number of kinases, moreover the so far most specific inhibitors act at least on these three major types of VEGF-Rs: Flt-1, Flk-1/KDR, Flt-4. The goal is a selective VEGF-R-2 (Flk-1/KDR) inhibitor, because this receptor triggers rather unspecific signals from VEGF-A, -C, -D and -E. Here, we describe a protocol starting from an established inhibitor (Vatalanib) with 2D-/3D-searching and property filtering of the in silico screening hits and the "negative docking approach". With this approach we were able to identify a compound, which shows a fourfold higher reduction of the proliferation rate of endothelial cells compared to the reduction effect of the lead structure.

  16. Design, validation and efficacy of bisubstrate inhibitors specifically affecting ecto-CK2 kinase activity.

    Science.gov (United States)

    Cozza, Giorgio; Zanin, Sofia; Sarno, Stefania; Costa, Elena; Girardi, Cristina; Ribaudo, Giovanni; Salvi, Mauro; Zagotto, Giuseppe; Ruzzene, Maria; Pinna, Lorenzo A

    2015-11-01

    By derivatizing the purely competitive CK2 inhibitor N1-(4,5,6,7-tetrabromo-1H-benzimidazol-2-yl)-propane-1,3-diamine (K137) at its 3-amino position with a peptidic fragment composed of three or four glutamic or aspartic acid residues, a new family of bisubstrate inhibitors has been generated whose ability to simultaneously interact with both the ATP and the phosphoacceptor substrate-binding sites has been probed by running mixed competition kinetics and by mutational mapping of the kinase residues implicated in substrate recognition. The most effective bisubstrate inhibitor, K137-E4, interacts with three functional regions of the kinase: the hydrophobic pocket close to the ATP-binding site, the basic residues of the p+1 loop that recognizes the acidic determinant at position n+1 and the basic residues of α-helixC that recognize the acidic determinant at position n+3. Compared with the parent inhibitor (K137), K137-E4 is severalfold more potent (IC50 25 compared with 130 nM) and more selective, failing to inhibit any other kinase as drastically as CK2 out of 140 enzymes, whereas 35 kinases are inhibited more potently than CK2 by K137. K137-E4 is unable to penetrate the cell and to inhibit endogenous CK2, its pro-apoptotic efficacy being negligible compared with cell-permeant inhibitors; however, it readily inhibits ecto-CK2 on the outer cell surface, reducing the phosphorylation of several external phosphoproteins. Inhibition of ecto-CK2 by K137-E4 is accompanied by a slower migration of cancer cells as judged by wound healing assays. On the basis of the cellular responses to K137-E4, we conclude that ecto-CK2 is implicated in cell motility, whereas its contribution to the pro-survival role of CK2 is negligible. PMID:26349539

  17. Antineoplastic effects of an Aurora B kinase inhibitor in breast cancer

    Directory of Open Access Journals (Sweden)

    Velazquez-Torres Guermarie

    2010-02-01

    Full Text Available Abstract Background Aurora B kinase is an important mitotic kinase involved in chromosome segregation and cytokinesis. It is overexpressed in many cancers and thus may be an important molecular target for chemotherapy. AZD1152 is the prodrug for AZD1152-HQPA, which is a selective inhibitor of Aurora B kinase activity. Preclinical antineoplastic activity of AZD1152 against acute myelogenous leukemia, multiple myeloma and colorectal cancer has been reported. However, this compound has not been evaluated in breast cancer, the second leading cause of cancer deaths among women. Results The antineoplastic activity of AZD1152-HQPA in six human breast cancer cell lines, three of which overexpress HER2, is demonstrated. AZD1152-HQPA specifically inhibited Aurora B kinase activity in breast cancer cells, thereby causing mitotic catastrophe, polyploidy and apoptosis, which in turn led to apoptotic death. AZD1152 administration efficiently suppressed the tumor growth in a breast cancer cell xenograft model. In addition, AZD1152 also inhibited pulmonary metastatic nodule formation in a metastatic breast cancer model. Notably, it was also found that the protein level of Aurora B kinase declined after inhibition of Aurora B kinase activity by AZD1152-HQPA in a time- and dose-dependent manner. Investigation of the underlying mechanism suggested that AZD1152-HQPA accelerated protein turnover of Aurora B via enhancing its ubiquitination. Conclusions It was shown that AZD1152 is an effective antineoplastic agent for breast cancer, and our results define a novel mechanism for posttranscriptional regulation of Aurora B after AZD1152 treatment and provide insight into dosing regimen design for this kinase inhibitor in metastatic breast cancer treatment.

  18. Anti-Angiogenic Therapy: Strategies to Develop Potent VEGFR-2 Tyrosine Kinase Inhibitors and Future Prospect.

    Science.gov (United States)

    Shi, Leilei; Zhou, Jianfeng; Wu, Jifeng; Shen, Yuemao; Li, Xun

    2016-01-01

    Tumor angiogenesis has always been a major gap for effective cancer therapy. Interruption of aberrant angiogenesis by specific inhibitors targeting receptor tyrosine kinases (RTKs) has been of great interests to medicinal chemists. Among the factors that are involved in tumor angiogenesis, vascular endothelial growth factor receptor-2 (VEGFR-2) is validated as the most closely related factor which can drive angiogenesis through binding with its natural ligand VEGF. The well-validated VEGF-driven VEGFR-2 signaling pathway can stimulate many endothelial responses, including increasing vessel permeability and enhancing endothelial cell proliferation, migration and differentiation. Consequently, circumventing angiogenesis by VEGFR-2 inhibitors represents a promising strategy for counteracting various VEGFR-2-mediated disorders as well as drug resistance. Over the past decades, a considerable number of novel small molecular VEGFR-2 inhibitors have been exploited with diverse chemical scaffolds. Especially, recent frequently launched inhibitors have declared their research values and therapeutic potentials in oncology. Still, the antiangiogenesis based treatment remains an ongoing challenge. In this review, a comprehensive retrospective of newly emerged VEGFR-2 inhibitors have been summarized, with the emphasis on the structure-activity relationship (SAR) investigation, and also binding patterns of representative inhibitors with biotargets. On the basis of all of this information, varied strategies for developing potent VEGFR-2 inhibitors and the future prospect of the clinical application of antiangiogenic inhibitors are discussed hereby.

  19. Focal adhesion kinase as a mechanotransducer during rapid brain growth of the chick embryo.

    Science.gov (United States)

    Desmond, Mary E; Knepper, Janice E; DiBenedetto, Angela J; Malaugh, Elizabeth; Callejo, Sagrario; Carretero, Raquel; Alonso, Maria-Isabel; Gato, Angel

    2014-01-01

    Expansion of the hollow fluid-filled embryonic brain occurs by an increase in intraluminal pressure created by accumulation of cerebrospinal fluid (CSF). Experiments have shown a direct correlation between cavity pressure and cell proliferation within the neuroepithelium. These findings lead us to ask how mechanistically this might come about. Are there perhaps molecules on the luminal surface of the embryonic neuroepithelium, such as focal adhesion kinases (FAKs) known to respond to tension in other epithelial cells? Immunodetection using antibodies to total FAK and p-FAK was performed with subsequent confocal analysis of the pattern of their activation under normal intraluminal pressure and induced chronic pressure. Western analysis was also done to look at the amount of FAK expression, as well as its activation under these same conditions. Using immunolocalization, we have shown that FAK is present and activated on both apical and basolateral surfaces and within the cytoplasm of the neuroepithelial cells. This pattern changed profoundly when the neuroepithelium was under pressure. By Western blot, we have shown that FAK was upregulated and activated in the neuroepithelium of the embryos just after the neural tube becomes a closed pressurized system, with phosphorylation detected on the luminal instead of the basal surface, along with an increase in cell proliferation. Chronic hyper-pressure does not induce an increase in phosphorylation of FAK. In conclusion, here we show that neuroepithelial cells respond to intraluminal pressure via FAK phosphorylation on the luminal surface. PMID:24860993

  20. Adhesion

    Science.gov (United States)

    As the body moves, tissues or organs inside are normally able to shift around each other. This is because these tissues have ... occur if the adhesions cause an organ or body part to: Twist Pull ... unable to move normally The risk of forming adhesions is high ...

  1. Focal Adhesion Kinase Is Required for Intestinal Regeneration and Tumorigenesis Downstream of Wnt/c-Myc Signaling

    OpenAIRE

    Ashton, Gabrielle H.; Morton, Jennifer P; Myant, Kevin; Phesse, Toby J.; Ridgway, Rachel A.; Marsh, Victoria; Wilkins, Julie A.; Athineos, Dimitris; Muncan, Vanesa; Kemp, Richard; Neufeld, Kristi; Clevers, Hans; Brunton, Valerie; Winton, Douglas J.; Wang, Xiaoyan

    2010-01-01

    The intestinal epithelium has a remarkable capacity to regenerate after injury and DNA damage. Here, we show that the integrin effector protein Focal Adhesion Kinase (FAK) is dispensable for normal intestinal homeostasis and DNA damage signaling, but is essential for intestinal regeneration following DNA damage. Given Wnt/c-Myc signaling is activated following intestinal regeneration, we investigated the functional importance of FAK following deletion of the Apc tumor suppressor protein withi...

  2. Role of tyrosine-kinase inhibitors in myeloproliferative neoplasms: comparative lessons learned

    Science.gov (United States)

    Pinilla-Ibarz, Javier; Sweet, Kendra L; Corrales-Yepez, Gabriela M; Komrokji, Rami S

    2016-01-01

    An important pathogenetic distinction in the classification of myeloproliferative neoplasms (MPNs) is the presence or absence of the BCR–ABL fusion gene, which encodes a unique oncogenic tyrosine kinase. The BCR–ABL fusion, caused by the formation of the Philadelphia chromosome (Ph) through translocation, constitutes the disease-initiating event in chronic myeloid leukemia. The development of successive BCR–ABL-targeted tyrosine-kinase inhibitors has led to greatly improved outcomes in patients with chronic myeloid leukemia, including high rates of complete hematologic, cytogenetic, and molecular responses. Such levels of treatment success have long been elusive for patients with Ph-negative MPNs, because of the difficulties in identifying specific driver proteins suitable as drug targets. However, in recent years an improved understanding of the complex pathobiology of classic Ph-negative MPNs, characterized by variable, overlapping multimutation profiles, has prompted the development of better and more broadly targeted (to pathway rather than protein) treatment options, particularly JAK inhibitors. In classic Ph-negative MPNs, overactivation of JAK-dependent signaling pathways is a central pathogenic mechanism, and mutually exclusive mutations in JAK2, MPL, and CALR linked to aberrant JAK activation are now recognized as key drivers of disease progression in myelofibrosis (MF). In clinical trials, the JAK1/JAK2 inhibitor ruxolitinib – the first therapy approved for MF worldwide – improved disease-related splenomegaly and symptoms independent of JAK2V617F mutational status, and prolonged survival compared with placebo or standard therapy in patients with advanced MF. In separate trials, ruxolitinib also provided comprehensive hematologic control in patients with another Ph-negative MPN – polycythemia vera. However, complete cytogenetic or molecular responses with JAK inhibitors alone are normally not observed, underscoring the need for novel

  3. The Recent Medicinal Chemistry Development of Jak2 Tyrosine Kinase Small Molecule Inhibitors

    OpenAIRE

    Baskin, Rebekah; Majumder, Anurima; Sayeski, Peter P.

    2010-01-01

    Since the discovery of the Jak2-V617F mutation as the causative agent in a large number of myeloproliferative neoplasms (MPNs), there has been a drive to develop Jak2 specific inhibitors that can be used in therapy for MPN patients and other Jak2-related pathologies. Over the past few years, a number of research groups have sought to develop Jak2 tyrosine kinase inhibitors. These compounds are currently in pre-clinical or clinical trials. Unfortunately, there is still a need for more potent, ...

  4. Overall survival after immunotherapy, tyrosine kinase inhibitors and surgery in treatment of metastatic renal cell cancer

    DEFF Research Database (Denmark)

    de Lichtenberg, Trine Honnens; Hermann, Gregers G.; Rorth, Mikael;

    2014-01-01

    , stage, performance status and white cell blood count were related to poor OS. Using multivariate analyses to adjust for risk predictors the difference in OS disappeared. Median OS before and after introduction of TKIs was 16 months and 14 months, respectively (p = 0.189). Memorial Sloan Kettering Cancer......Abstract Objective. The aim of this study was to evaluate overall survival (OS) after treatment of metastatic renal cell carcinoma (mRCC) following the introduction of tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin (mTOR) inhibitors. Material and methods. One-hundred and forty...

  5. Combining RNA interference and kinase inhibitors against cell signalling components involved in cancer

    Directory of Open Access Journals (Sweden)

    Hanson Bonnie J

    2005-10-01

    Full Text Available Abstract Background The transcription factor activator protein-1 (AP-1 has been implicated in a large variety of biological processes including oncogenic transformation. The tyrosine kinases of the epidermal growth factor receptor (EGFR constitute the beginning of one signal transduction cascade leading to AP-1 activation and are known to control cell proliferation and differentiation. Drug discovery efforts targeting this receptor and other pathway components have centred on monoclonal antibodies and small molecule inhibitors. Resistance to such inhibitors has already been observed, guiding the prediction of their use in combination therapies with other targeted agents such as RNA interference (RNAi. This study examines the use of RNAi and kinase inhibitors for qualification of components involved in the EGFR/AP-1 pathway of ME180 cells, and their inhibitory effects when evaluated individually or in tandem against multiple components of this important disease-related pathway. Methods AP-1 activation was assessed using an ME180 cell line stably transfected with a beta-lactamase reporter gene under the control of AP-1 response element following epidermal growth factor (EGF stimulation. Immunocytochemistry allowed for further quantification of small molecule inhibition on a cellular protein level. RNAi and RT-qPCR experiments were performed to assess the amount of knockdown on an mRNA level, and immunocytochemistry was used to reveal cellular protein levels for the targeted pathway components. Results Increased potency of kinase inhibitors was shown by combining RNAi directed towards EGFR and small molecule inhibitors acting at proximal or distal points in the pathway. After cellular stimulation with EGF and analysis at the level of AP-1 activation using a β-lactamase reporter gene, a 10–12 fold shift or 2.5–3 fold shift toward greater potency in the IC50 was observed for EGFR and MEK-1 inhibitors, respectively, in the presence of RNAi

  6. Protein kinase C-β inhibitor treatment attenuates hepatic ischemia and reperfusion injury in diabetic rats

    OpenAIRE

    MENG, GUANG-XING; Yuan, Qiang; WEI, LI-PING; Meng, Hua; Wang, Yi-Jun

    2015-01-01

    Hepatic ischemia and reperfusion (I/R) injury plays an active role in hepatic resection and transplantation. While the effects of protein kinase C (PKC)-βII activation and the role of PKC-β inhibitors are well understood in myocardial I/R in diabetes, they remain unclear in liver I/R. The aim of this study was to explore the effect of PKC-β inhibition and the potential mechanism by which PKC-β inhibitor treatment protects against hepatic I/R injury in diabetic rats. Diabetic rats were establi...

  7. Role of tyrosine-kinase inhibitors in myeloproliferative neoplasms: comparative lessons learned

    Directory of Open Access Journals (Sweden)

    Pinilla-Ibarz J

    2016-08-01

    Full Text Available Javier Pinilla-Ibarz, Kendra L Sweet, Gabriela M Corrales-Yepez, Rami S Komrokji Department of Malignant Hematology, H Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA Abstract: An important pathogenetic distinction in the classification of myeloproliferative neoplasms (MPNs is the presence or absence of the BCR–ABL fusion gene, which encodes a unique oncogenic tyrosine kinase. The BCR–ABL fusion, caused by the formation of the Philadelphia chromosome (Ph through translocation, constitutes the disease-initiating event in chronic myeloid leukemia. The development of successive BCR–ABL-targeted tyrosine-kinase inhibitors has led to greatly improved outcomes in patients with chronic myeloid leukemia, including high rates of complete hematologic, cytogenetic, and molecular responses. Such levels of treatment success have long been elusive for patients with Ph-negative MPNs, because of the difficulties in identifying specific driver proteins suitable as drug targets. However, in recent years an improved understanding of the complex pathobiology of classic Ph-negative MPNs, characterized by variable, overlapping multimutation profiles, has prompted the development of better and more broadly targeted (to pathway rather than protein treatment options, particularly JAK inhibitors. In classic Ph-negative MPNs, overactivation of JAK-dependent signaling pathways is a central pathogenic mechanism, and mutually exclusive mutations in JAK2, MPL, and CALR linked to aberrant JAK activation are now recognized as key drivers of disease progression in myelofibrosis (MF. In clinical trials, the JAK1/JAK2 inhibitor ruxolitinib – the first therapy approved for MF worldwide – improved disease-related splenomegaly and symptoms independent of JAK2V617F mutational status, and prolonged survival compared with placebo or standard therapy in patients with advanced MF. In separate trials, ruxolitinib also provided comprehensive hematologic control in

  8. Quinalizarin as a potent, selective and cell permeable inhibitor of protein kinase CK2

    OpenAIRE

    Cozza, Giorgio; Mazzorana, Marco; Papinutto, Elena; Bain, Jenny; Elliott, Matthew; Di Maira, Giovanni; Gianoncelli, Alessandra; Pagano, Mario A.; Sarno, Stefania; Ruzzene, Maria; Battistutta, Roberto; Meggio, Flavio; Moro, Stefano; Zagotto, Giuseppe; Pinna, Lorenzo A.

    2009-01-01

    Abstract Emodin (1,3,8-trihydroxy-6-methyl-anthraquinone) is a moderately potent and poorly selective inhibitor of CK2, one of the most pleiotropic Ser/Thr protein kinases, implicated in neoplasia and in other global diseases. By virtual screening of the MMS database we have now identified quinalizarin (1,2,5,8-tetrahydroxy-anthraquinone) as an inhibitor of CK2 more potent and selective than emodin. CK2 inhibition by quinalizarin is competitive with respect to ATP, with a Ki value ...

  9. Enhanced susceptibility of cyclin kinase inhibitor p21 knockout mice to high fat diet induced atherosclerosis

    OpenAIRE

    Khanna Ashwani K

    2009-01-01

    Abstract Cyclin kinase inhibitor p21 is one of the most potent inhibitors of aortic smooth muscle cell proliferation, a key mediator of atherosclerosis. This study tests if p2l deficiency will result in severe atherosclerosis in a mouse model. p21-/- and strain matched wild type mice were fed with high fat diet for 21 weeks. Analysis for biochemical parameters (cholesterol, triglycerides) in serum and mRNA expression of CD36, HO-1, TGF-β, IFN-γ, TNF-α, PPAR-γ and NADPH oxidase components (p22...

  10. Alteration of radiation response by two tyrosine kinase inhibitors: STI571 (Glivec) and BIBW 2992

    International Nuclear Information System (INIS)

    Concurrent chemo-radiation is one of the main weapon in the treatment of cancer. The targeted therapies may act on the mechanisms of tumor resistance to radiation and are therefore very promising in combination with radiotherapy. The STI571 (imatinib or Gleevec) inhibits specifically the Bcr-Abl tyrosine kinase. It leads to radiosensitization in K562 chronic myeloid leukemia cell line by alterations of the cell cycle. The BIBW2992 is a selective inhibitor of EGFR and HER2. The BIBW 2992 shows cytotoxic and radiosensitizing effects on pancreatic adenocarcinoma cells BxPC3 and Capan-2, regardless of KRAS status. The mechanism underlying this radiosensitization is not unequivocal, involving both changes in the cell cycle and induction of mitotic death. Our results show that the combination of an inhibitor of tyrosine kinase with ionizing radiation may lead to a radiosensitization in vitro with mechanisms depending on the type of cell line. (author)

  11. Masitinib (AB1010, a potent and selective tyrosine kinase inhibitor targeting KIT.

    Directory of Open Access Journals (Sweden)

    Patrice Dubreuil

    Full Text Available BACKGROUND: The stem cell factor receptor, KIT, is a target for the treatment of cancer, mastocytosis, and inflammatory diseases. Here, we characterise the in vitro and in vivo profiles of masitinib (AB1010, a novel phenylaminothiazole-type tyrosine kinase inhibitor that targets KIT. METHODOLOGY/PRINCIPAL FINDINGS: In vitro, masitinib had greater activity and selectivity against KIT than imatinib, inhibiting recombinant human wild-type KIT with an half inhibitory concentration (IC(50 of 200+/-40 nM and blocking stem cell factor-induced proliferation and KIT tyrosine phosphorylation with an IC(50 of 150+/-80 nM in Ba/F3 cells expressing human or mouse wild-type KIT. Masitinib also potently inhibited recombinant PDGFR and the intracellular kinase Lyn, and to a lesser extent, fibroblast growth factor receptor 3. In contrast, masitinib demonstrated weak inhibition of ABL and c-Fms and was inactive against a variety of other tyrosine and serine/threonine kinases. This highly selective nature of masitinib suggests that it will exhibit a better safety profile than other tyrosine kinase inhibitors; indeed, masitinib-induced cardiotoxicity or genotoxicity has not been observed in animal studies. Molecular modelling and kinetic analysis suggest a different mode of binding than imatinib, and masitinib more strongly inhibited degranulation, cytokine production, and bone marrow mast cell migration than imatinib. Furthermore, masitinib potently inhibited human and murine KIT with activating mutations in the juxtamembrane domain. In vivo, masitinib blocked tumour growth in mice with subcutaneous grafts of Ba/F3 cells expressing a juxtamembrane KIT mutant. CONCLUSIONS: Masitinib is a potent and selective tyrosine kinase inhibitor targeting KIT that is active, orally bioavailable in vivo, and has low toxicity.

  12. Molecular Docking and NMR Binding Studies to Identify Novel Inhibitors of Human Phosphomevalonate Kinase

    OpenAIRE

    Boonsri, Pornthip; Neumann, Terrence S.; Olson, Andrew L.; Cai, Sheng; Herdendorf, Timothy J.; Miziorko, Henry M.; Hannongbua, Supa; Sem, Daniel S.

    2012-01-01

    Phosphomevalonate kinase (PMK) phosphorylates mevalonate-5-phosphate (M5P) in the mevalonate pathway, which is the sole source of isoprenoids and steroids in humans. We have identified new PMK inhibitors with virtual screening, using Autodock. Promising hits were verified and their affinity measured using NMR-based 1H-15N Heteronuclear Single Quantum Coherence (HSQC) chemical shift perturbation and fluorescence titrations. Chemical shift changes were monitored, plotted, and fitted to obtain d...

  13. Comparison of the Radiosensitizing Effect of ATR, ATM and DNA-PK Kinase Inhibitors on Cervical Carcinoma Cells.

    Science.gov (United States)

    Vávrová, J; Zárybnická, L; Jošt, P; Tichý, A; Řezáčová, M; Šinkorová, Z; Pejchal, J

    2016-01-01

    Here, we compared the effects of inhibitors of three phosphatidylinositol-3-kinase-related kinases, ATM, ATR a DNA-PK, on radiosensitization of cervical carcinoma cells. We demonstrated that DNA-PK inhibitor NU7441 enhanced phosphorylation of Chk1 and Chk2 kinases 2 h after irradiation of HeLa cells at a dose of 8 Gy in contrast to ATM kinase inhibitor KU55933, which completely blocked the Chk2 kinase phosphorylation on threonine 68, and ATR kinase inhibitor VE-821, which blocked the Chk1 kinase phosphorylation on serine 345. Most HeLa cells were accumulated in G2 phase of the cell cycle 24 h after irradiation at a high dose of 15 Gy, which was even potentiated after adding the inhibitors NU7441 and KU55933. Compared to all other irradiated groups, inhibitor VE-821 increased the number of cells in S phase and reduced the number of cells in G2 phase 24 h after irradiation at the high dose of 15 Gy. HeLa cells entered the mitotic cycle with unrepaired DNA, which resulted in cell death and the radiosensitizing effect of VE-821. Short-term application of the inhibitors (2 h before and 30 min after the irradiation by the dose of 8 Gy) significantly decreased the colony-forming ability of HeLa cells. Using real-time monitoring of cell proliferation by the xCELLigence system we demonstrated that while the radiosensitizing effect of VE-821 (ATR inhibitor) is manifested early after the irradiation, the radiosensitizing effect of KU55933 (ATM inhibitor) and NU7441 (DNA-PK inhibitor) is only observed as late as 72 h after the irradiation. PMID:27643582

  14. Identification and Characterization of Amlexanox as a G Protein-Coupled Receptor Kinase 5 Inhibitor

    Directory of Open Access Journals (Sweden)

    Kristoff T. Homan

    2014-10-01

    Full Text Available G protein-coupled receptor kinases (GRKs have been implicated in human diseases ranging from heart failure to diabetes. Previous studies have identified several compounds that selectively inhibit GRK2, such as paroxetine and balanol. Far fewer selective inhibitors have been reported for GRK5, a target for the treatment of cardiac hypertrophy, and the mechanism of action of reported compounds is unknown. To identify novel scaffolds that selectively inhibit GRK5, a differential scanning fluorometry screen was used to probe a library of 4480 compounds. The best hit was amlexanox, an FDA-approved anti-inflammatory, anti-allergic immunomodulator. The crystal structure of amlexanox in complex with GRK1 demonstrates that its tricyclic aromatic ring system forms ATP-like interactions with the hinge of the kinase domain, which is likely similar to how this drug binds to IκB kinase ε (IKKε, another kinase known to be inhibited by this compound. Amlexanox was also able to inhibit myocyte enhancer factor 2 transcriptional activity in neonatal rat ventricular myocytes in a manner consistent with GRK5 inhibition. The GRK1 amlexanox structure thus serves as a springboard for the rational design of inhibitors with improved potency and selectivity for GRK5 and IKKε.

  15. Discovery of Novel Fibroblast Growth Factor Receptor 1 Kinase Inhibitors by Structure-Based Virtual Screening

    Energy Technology Data Exchange (ETDEWEB)

    Ravindranathan, K.; Mandiyan, V; Ekkati, A; Bae, J; Schlessinger, J; Jorgensen, W

    2010-01-01

    Fibroblast growth factors (FGFs) play important roles in embryonic development, angiogenesis, wound healing, and cell proliferation and differentiation. In search of inhibitors of FGFR1 kinase, 2.2 million compounds were docked into the ATP binding site of the protein. A co-crystal structure, which shows two alternative conformations for the nucleotide binding loop, is reported. Docking was performed on both conformations and, ultimately, 23 diverse compounds were purchased and assayed. Following hit validation, two compounds 10 and 16, a benzylidene derivative of pseudothiohydantoin and a thienopyrimidinone derivative, respectively, were discovered that inhibit FGFR1 kinase with IC{sub 50} values of 23 and 50 {micro}M. Initial optimization of 16 led to the more unsaturated 40, which has significantly enhanced potency, 1.9 {micro}M. The core structures represent new structural motifs for FGFR1 kinase inhibitors. The study also illustrates complexities associated with the choice of protein structures for docking, possible use of multiple kinase structures to seek selectivity, and hit identification.

  16. Radiosensitization of Human Leukemic HL-60 Cells by ATR Kinase Inhibitor (VE-821: Phosphoproteomic Analysis

    Directory of Open Access Journals (Sweden)

    Barbora Šalovská

    2014-07-01

    Full Text Available DNA damaging agents such as ionizing radiation or chemotherapy are frequently used in oncology. DNA damage response (DDR—triggered by radiation-induced double strand breaks—is orchestrated mainly by three Phosphatidylinositol 3-kinase-related kinases (PIKKs: Ataxia teleangiectasia mutated (ATM, DNA-dependent protein kinase (DNA-PK and ATM and Rad3-related kinase (ATR. Their activation promotes cell-cycle arrest and facilitates DNA damage repair, resulting in radioresistance. Recently developed specific ATR inhibitor, VE-821 (3-amino-6-(4-(methylsulfonylphenyl-N-phenylpyrazine-2-carboxamide, has been reported to have a significant radio- and chemo-sensitizing effect delimited to cancer cells (largely p53-deficient without affecting normal cells. In this study, we employed SILAC-based quantitative phosphoproteomics to describe the mechanism of the radiosensitizing effect of VE-821 in human promyelocytic leukemic cells HL-60 (p53-negative. Hydrophilic interaction liquid chromatography (HILIC-prefractionation with TiO2-enrichment and nano-liquid chromatography—tandem mass spectrometry (LC-MS/MS analysis revealed 9834 phosphorylation sites. Proteins with differentially up-/down-regulated phosphorylation were mostly localized in the nucleus and were involved in cellular processes such as DDR, all phases of the cell cycle, and cell division. Moreover, sequence motif analysis revealed significant changes in the activities of kinases involved in these processes. Taken together, our data indicates that ATR kinase has multiple roles in response to DNA damage throughout the cell cycle and that its inhibitor VE-821 is a potent radiosensitizing agent for p53-negative HL-60 cells.

  17. Tyrosine Kinase Inhibitors Induced Thyroid Dysfunction: A Review of Its Incidence, Pathophysiology, Clinical Relevance, and Treatment

    Directory of Open Access Journals (Sweden)

    Hala Ahmadieh

    2013-01-01

    Full Text Available Tyrosine kinase inhibitors (TKI belong to a new class of molecular multitargeted anticancer therapy which targets different growth factor receptors and hence attenuates cancer cell survival and growth. Since their introduction as adjunct treatment for renal cell carcinoma and gastrointestinal stromal tumors (GIST, a number of reports have demonstrated that TKI can induce thyroid dysfunction which was especially more common with sunitinib maleate. Many mechanisms with respect to this adverse effect of tyrosine kinase inhibitors have been proposed including their induction of thyroiditis, capillary regression in the thyroid gland, antithyroid peroxidase antibody production, and their ability to decrease iodine uptake by the thyroid gland. Of interest is the observation that TKI-induced thyroid dysfunction may actually be protective as it was shown to improve overall survival, and it was suggested that it may have a prognostic value. Followup on thyroid function tests while patients are maintained on tyrosine kinase inhibitor is strongly recommended. When thyroid dysfunction occurs, appropriate treatment should be individualized depending on patients symptoms and thyroid stimulating hormone level.

  18. Mesenchymal stem cells are sensitive to treatment with kinase inhibitors and ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nicolay, Nils H.; Debus, Juergen; Huber, Peter E. [Heidelberg University Hospital, Department of Radiation Oncology, Heidelberg (Germany); German Cancer Research Center (dkfz), Department of Molecular and Radiation Oncology, Heidelberg (Germany); Sommer, Eva; Lopez Perez, Ramon; Wirkner, Ute [German Cancer Research Center (dkfz), Department of Molecular and Radiation Oncology, Heidelberg (Germany); Bostel, Tilman [Heidelberg University Hospital, Department of Radiation Oncology, Heidelberg (Germany); Ho, Anthony D.; Saffrich, Rainer [Heidelberg University Hospital, Department of Hematology, Oncology and Rheumatology, Heidelberg (Germany); Lahn, Michael [Lilly Research Laboratories, Oncology Early Clinical Investigation, Indianapolis, IN (United States)

    2014-11-15

    Mesenchymal stem cells (MSCs) can regenerate damaged tissues and may therefore be of importance for normal tissue repair after cancer treatment. Small molecule receptor kinase inhibitors (RKIs) have recently been introduced into cancer treatment. However, the influence of these drugs - particularly in combination with radiotherapy - on the survival of MSCs is largely unknown. The sensitivity of human primary MSCs from healthy volunteers and primary human fibroblast cells to small molecule kinase inhibitors of the vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ) receptors, as well to inhibitors of c-Kit, was examined in combination with ionizing radiation (IR); cell survival and proliferation were assessed. Expression patterns of different kinase receptors and ligands were investigated using gene arrays. MSCs were highly sensitive to the tyrosine kinase inhibitors SU14816 (imatinib) and SU11657 (sunitinib), but showed only moderate sensitivity to the selective TGFβ receptor 1 inhibitor LY2109761. Primary adult human fibroblasts were comparably resistant to all three inhibitors. The addition of IR had an additive or supra-additive effect in the MSCs, but this was not the case for differentiated fibroblasts. Proliferation was markedly reduced in MSCs following kinase inhibition, both with and without IR. Gene expression analysis revealed high levels of the PDGF α and β receptors, and lower levels of the TGFβ receptor 2 and Abl kinase. IR did not alter the expression of kinase receptors or their respective ligands in either MSCs or adult fibroblasts. These data show that MSCs are highly sensitive to RKIs and combination treatments incorporating IR. Expression analyses suggest that high levels of PDGF receptors may contribute to this effect. (orig.) [German] Mesenchymale Stammzellen (MSCs) koennen die Geweberegeneration unterstuetzen und haben daher moeglicherweise eine Rolle bei der Reparatur

  19. Organization and post-transcriptional processing of focal adhesion kinase gene

    Directory of Open Access Journals (Sweden)

    Enslen Hervé

    2006-08-01

    Full Text Available Abstract Background Focal adhesion kinase (FAK is a non-receptor tyrosine kinase critical for processes ranging from embryo development to cancer progression. Although isoforms with specific molecular and functional properties have been characterized in rodents and chicken, the organization of FAK gene throughout phylogeny and its potential to generate multiple isoforms are not well understood. Here, we study the phylogeny of FAK, the organization of its gene, and its post-transcriptional processing in rodents and human. Results A single orthologue of FAK and the related PYK2 was found in non-vertebrate species. Gene duplication probably occurred in deuterostomes after the echinoderma embranchment, leading to the evolution of PYK2 with distinct properties. The amino acid sequence of FAK and PYK2 is conserved in their functional domains but not in their linker regions, with the absence of autophosphorylation site in C. elegans. Comparison of mouse and human FAK genes revealed the existence of multiple combinations of conserved and non-conserved 5'-untranslated exons in FAK transcripts suggesting a complex regulation of their expression. Four alternatively spliced coding exons (13, 14, 16, and 31, previously described in rodents, are highly conserved in vertebrates. Cis-regulatory elements known to regulate alternative splicing were found in conserved alternative exons of FAK or in the flanking introns. In contrast, other reported human variant exons were restricted to Homo sapiens, and, in some cases, other primates. Several of these non-conserved exons may correspond to transposable elements. The inclusion of conserved alternative exons was examined by RT-PCR in mouse and human brain during development. Inclusion of exons 14 and 16 peaked at the end of embryonic life, whereas inclusion of exon 13 increased steadily until adulthood. Study of various tissues showed that inclusion of these exons also occurred, independently from each other, in a

  20. Structure-Activity Relationship Studies of Mitogen Activated Protein Kinase Interacting Kinase (MNK) 1 and 2 and BCR-ABL1 Inhibitors Targeting Chronic Myeloid Leukemic Cells.

    Science.gov (United States)

    Cherian, Joseph; Nacro, Kassoum; Poh, Zhi Ying; Guo, Samantha; Jeyaraj, Duraiswamy A; Wong, Yun Xuan; Ho, Melvyn; Yang, Hai Yan; Joy, Joma Kanikadu; Kwek, Zekui Perlyn; Liu, Boping; Wee, John Liang Kuan; Ong, Esther H Q; Choong, Meng Ling; Poulsen, Anders; Lee, May Ann; Pendharkar, Vishal; Ding, Li Jun; Manoharan, Vithya; Chew, Yun Shan; Sangthongpitag, Kanda; Lim, Sharon; Ong, S Tiong; Hill, Jeffrey; Keller, Thomas H

    2016-04-14

    Clinically used BCR-ABL1 inhibitors for the treatment of chronic myeloid leukemia do not eliminate leukemic stem cells (LSC). It has been shown that MNK1 and 2 inhibitors prevent phosphorylation of eIF4E and eliminate the self-renewal capacity of LSCs. Herein, we describe the identification of novel dual MNK1 and 2 and BCR-ABL1 inhibitors, starting from the known kinase inhibitor 2. Initial structure-activity relationship studies resulted in compound 27 with loss of BCR-ABL1 inhibition. Further modification led to orally bioavailable dual MNK1 and 2 and BCR-ABL1 inhibitors 53 and 54, which are efficacious in a mouse xenograft model and also reduce the level of phosphorylated eukaryotic translation initiation factor 4E in the tumor tissues. Kinase selectivity of these compounds is also presented. PMID:27011159

  1. Identification of ellagic acid as potent inhibitor of protein kinase CK2: a successful example of a virtual screening application.

    Science.gov (United States)

    Cozza, Giorgio; Bonvini, Paolo; Zorzi, Elisa; Poletto, Giorgia; Pagano, Mario A; Sarno, Stefania; Donella-Deana, Arianna; Zagotto, Giuseppe; Rosolen, Angelo; Pinna, Lorenzo A; Meggio, Flavio; Moro, Stefano

    2006-04-20

    Casein kinase 2 (CK2) is a ubiquitous, essential, and highly pleiotropic protein kinase whose abnormally high constitutive activity is suspected to underlie its pathogenic potential in neoplasia and other diseases. Using a virtual screening approach, we have identified the ellagic acid, a naturally occurring tannic acid derivative, as a novel potent CK2 inhibitor. At present, ellagic acid represents the most potent known CK2 inhibitor (K(i) = 20 nM). PMID:16610779

  2. Modulation of human basophil histamine release by protein kinase C inhibitors differs with secretagogue and with inhibitor.

    Science.gov (United States)

    Bergstrand, H; Lundquist, B; Karabelas, K; Michelsen, P

    1992-03-01

    To assess possible involvement of protein kinase C (PKC) in human basophil degranulation, the present work compared effects of various purported PKC inhibitors on leukocyte histamine release triggered by different stimuli. The effects recorded varied with the inhibitor and the secretagogue used; moreover, with a given secretagogue, different inhibitors often displayed different activities. Thus, histamine release triggered by the PKC activator 4 beta-phorbol 12-myristate 13-acetate was blocked by K252a, staurosporine and the purported specific PKC inhibitor Ro 31-7549, and reduced by calphostin C, H-7, TMB-8 and W-7 but not affected by polymyxin B; it was augmented by 2.1 microM palmitoyl carnitine. The leukocyte response induced by another putative activator of PKC, 1,2-isopropylidene-3-decanoyl-sn-glycerol, was also enhanced by 2.1 microM palmitoyl carnitine, slightly increased by staurosporine, TMB-8 and W-7 but not affected by calphostin C, H-7, K252a or Ro 31-7549, whereas the hyperosmolar mannitol-induced response was reduced by H-7, calphostin C, TMB-8 and W-7 and slightly augmented by staurosporine. Anti-IgE-induced histamine release was blocked by staurosporine and K252a and reduced by calphostin C, sphingosine, TMB-8 and W-7 but not affected by H-7, polymyxin B or retinal. It was enhanced by Ro 31-7549. In contrast, leukocyte histamine release induced by calcium ionophore A23187 or by ionomycin was blocked by retinal, TMB-8 and W-7 and reduced by calphostin C and palmitoyl carnitine but enhanced by H-7, staurosporine and polymyxin B; K252a and Ro 31-7549 did not affect such responses. Formyl-methionyl-leucyl-phenylalanine-triggered histamine release was barely affected by any agent used. Thus, the specific PKC inhibitor Ro 31-7549 selectively blocked 4 beta-phorbol 12-myristate 13-acetate-triggered leukocyte histamine release. These results imply that examined secretagogues trigger human leukocyte histamine release through partly separate pathways

  3. Inhibition of dihydroceramide desaturase activity by the sphingosine kinase inhibitor SKI II.

    Science.gov (United States)

    Cingolani, Francesca; Casasampere, Mireia; Sanllehí, Pol; Casas, Josefina; Bujons, Jordi; Fabrias, Gemma

    2014-08-01

    Sphingosine kinase inhibitor (SKI) II has been reported as a dual inhibitor of sphingosine kinases (SKs) 1 and 2 and has been extensively used to prove the involvement of SKs and sphingosine-1-phosphate (S1P) in cellular processes. Dihydroceramide desaturase (Des1), the last enzyme in the de novo synthesis of ceramide (Cer), regulates the balance between dihydroceramides (dhCers) and Cers. Both SKs and Des1 have interest as therapeutic targets. Here we show that SKI II is a noncompetitive inhibitor (Ki = 0.3 μM) of Des1 activity with effect also in intact cells without modifying Des1 protein levels. Molecular modeling studies support that the SKI II-induced decrease in Des1 activity could result from inhibition of NADH-cytochrome b5 reductase. SKI II, but not the SK1-specific inhibitor PF-543, provoked a remarkable accumulation of dhCers and their metabolites, while both SKI II and PF-543 reduced S1P to almost undetectable levels. SKI II, but not PF543, reduced cell proliferation with accumulation of cells in the G0/G1 phase. SKI II, but not PF543, induced autophagy. These overall findings should be taken into account when using SKI II as a pharmacological tool, as some of the effects attributed to decreased S1P may actually be caused by augmented dhCers and/or their metabolites.

  4. JAK2 inhibition sensitizes resistant EGFR-mutant lung adenocarcinoma to tyrosine kinase inhibitors.

    Science.gov (United States)

    Gao, Sizhi P; Chang, Qing; Mao, Ninghui; Daly, Laura A; Vogel, Robert; Chan, Tyler; Liu, Shu Hui; Bournazou, Eirini; Schori, Erez; Zhang, Haiying; Red Brewer, Monica; Pao, William; Morris, Luc; Ladanyi, Marc; Arcila, Maria; Manova-Todorova, Katia; de Stanchina, Elisa; Norton, Larry; Levine, Ross L; Altan-Bonnet, Gregoire; Solit, David; Zinda, Michael; Huszar, Dennis; Lyden, David; Bromberg, Jacqueline F

    2016-01-01

    Lung adenocarcinomas with mutant epidermal growth factor receptor (EGFR) respond to EGFR-targeted tyrosine kinase inhibitors (TKIs), but resistance invariably occurs. We found that the Janus kinase (JAK)/signal transduction and activator of transcription 3 (STAT3) signaling pathway was aberrantly increased in TKI-resistant EGFR-mutant non-small cell lung cancer (NSCLC) cells. JAK2 inhibition restored sensitivity to the EGFR inhibitor erlotinib in TKI-resistant cell lines and xenograft models of EGFR-mutant TKI-resistant lung cancer. JAK2 inhibition uncoupled EGFR from its negative regulator, suppressor of cytokine signaling 5 (SOCS5), consequently increasing EGFR abundance and restoring the tumor cells' dependence on EGFR signaling. Furthermore, JAK2 inhibition led to heterodimerization of mutant and wild-type EGFR subunits, the activity of which was then blocked by TKIs. Our results reveal a mechanism whereby JAK2 inhibition overcomes acquired resistance to EGFR inhibitors and support the use of combination therapy with JAK and EGFR inhibitors for the treatment of EGFR-dependent NSCLC. PMID:27025877

  5. Akt Inhibitor A-443654 Interferes with Mitotic Progression by Regulating Aurora A Kinase Expression

    Directory of Open Access Journals (Sweden)

    Xuesong Liu

    2008-08-01

    Full Text Available Both Akt and Aurora A kinase have been shown to be important targets for intervention for cancer therapy. We report here that Compound A (A-443654, a specific Akt inhibitor, interferes with mitotic progression and bipolar spindle formation. Compound A induces G2/M accumulation, defects in centrosome separation, and formation of either monopolar arrays or disorganized spindles. On the basis of gene expression array studies, we identified Aurora A as one of the genes regulated transcriptionally by Akt inhibitors including Compound A. Inhibition of the phosphatidylinositol 3-kinase (PI3K/Akt pathway, either by PI3K inhibitor LY294002 or by Compound A, dramatically inhibits the promoter activity of Aurora A, whereas the mammalian target of rapamycin inhibitor has little effect, suggesting that Akt might be responsible for up-regulating Aurora A for mitotic progression. Further analysis of the Aurora A promoter region indicates that the Ets element but not the Sp1 element is required for Compound A-sensitive transcriptional control of Aurora A. Overexpression of Aurora A in cells treated with Compound A attenuates the mitotic arrest and the defects in bipolar spindle formation induced by Akt inhibition. Our studies suggest that that Akt may promote mitotic progression through the transcriptional regulation of Aurora A.

  6. Relationship between focal adhesion kinase and hepatic stellate cell proliferation during rat hepatic fibrogenesis

    Institute of Scientific and Technical Information of China (English)

    Hui-Qing Jiang; Xiao-Lan Zhang; Li Liu; Chang-Chun Yang

    2004-01-01

    AIM: To investigate the dynamic expression of focal adhesion kinase (FAK) protein and FAK mRNA in fibrotic rat liver tissue,and the relationship between FAK and hepatic stellate cell (HSC) proliferation.METHODS: Rat hepatic fibrosis was induced by bile duct ligation (BDL). Histopathological changes were evaluated by hematoxylin and eosin staining, and by Masson′s trichrome method. FAK mRNA in the rat livers was determined by reverse transcription-polymerase chain reaction (RT-PCR), and the distributions of FAK were assessed immunohistochemistrically.The number of activated HSCs was quantified after alpha smooth muscle actin (α-SMA) staining.RESULTS: With the development of hepatic fibrosis, the positively stained cells of α-SMA increased obviously, which were mainly resided in the portal ducts, fiber septa and perisinuses accompanied with proliferating bile ducts. The positively stained areas of the rat livers in model groups 1 to 4 wk after ligation of common bile duct (12.88±2.63%,22.65±2.16%, 27.45±1.86%, 35.25±2.34%, respectively)were significantly larger than those in the control group (5.88±1.46%) (P<0.01). The positive staining for FAK significantly increased, which was mainly situated in portal ducts, fiber septa and around the bile ducts, vascular endothelial cells and perisinusoidal cells. The expression of FAK was positively correlated with α-SMA expression (r = 0.963, P<0.05). FAK mRNA expression was obviously up-regulated in the model groups compared to the control group.CONCLUSION: These data suggest that expressions of FAK protein and mRNA are greatly increased in fibrotic rat livers,which may play an important role in HSC proliferation and hepatic fibrogenesis.

  7. Treatment of Breast Cancer Cells by IGF1R Tyrosine Kinase Inhibitor Combined with Conventional Systemic Drugs

    NARCIS (Netherlands)

    Hartog, H.; Van der Graaf, W. T. A.; Boezen, H. M.; Wesseling, J.

    2012-01-01

    Aim: Insulin-like growth factor-1 receptor (IGF1R) is a tyrosine kinase receptor mediating cell growth and survival of cancer cells. We studied responses to IGF1R tyrosine kinase inhibitor NVP-AEW541 combined with conventional systemic drugs in breast cancer cell lines of different clinical subtype.

  8. Treatment of breast cancer cells by IGF1R tyrosine kinase inhibitor combined with conventional systemic drugs.

    NARCIS (Netherlands)

    Hartog, H.; Graaf, W.T.A. van der; Boezen, H.M.; Wesseling, J.

    2012-01-01

    AIM: Insulin-like growth factor-1 receptor (IGF1R) is a tyrosine kinase receptor mediating cell growth and survival of cancer cells. We studied responses to IGF1R tyrosine kinase inhibitor NVP-AEW541 combined with conventional systemic drugs in breast cancer cell lines of different clinical subtype.

  9. Discovery of pyrrolo[1,2-b]pyridazine-3-carboxamides as Janus kinase (JAK) inhibitors.

    Science.gov (United States)

    Duan, James J-W; Lu, Zhonghui; Jiang, Bin; Yang, Bingwei V; Doweyko, Lidia M; Nirschl, David S; Haque, Lauren E; Lin, Shuqun; Brown, Gregory; Hynes, John; Tokarski, John S; Sack, John S; Khan, Javed; Lippy, Jonathan S; Zhang, Rosemary F; Pitt, Sidney; Shen, Guoxiang; Pitts, William J; Carter, Percy H; Barrish, Joel C; Nadler, Steven G; Salter-Cid, Luisa M; McKinnon, Murray; Fura, Aberra; Schieven, Gary L; Wrobleski, Stephen T

    2014-12-15

    A new class of Janus kinase (JAK) inhibitors was discovered using a rationally designed pyrrolo[1,2-b]pyridazine-3-carboxamide scaffold. Preliminary studies identified (R)-(2,2-dimethylcyclopentyl)amine as a preferred C4 substituent on the pyrrolopyridazine core (3b). Incorporation of amino group to 3-position of the cyclopentane ring resulted in a series of JAK3 inhibitors (4g-4j) that potently inhibited IFNγ production in an IL2-induced whole blood assay and displayed high functional selectivity for JAK3-JAK1 pathway relative to JAK2. Further modifications led to the discovery of an orally bioavailable (2-fluoro-2-methylcyclopentyl)amino analogue 5g which is a nanomolar inhibitor of both JAK3 and TYK2, functionally selective for the JAK3-JAK1 pathway versus JAK2, and active in a human whole blood assay. PMID:25453808

  10. Sulfonylpiperidines as novel, antibacterial inhibitors of Gram-positive thymidylate kinase (TMK).

    Science.gov (United States)

    Martínez-Botella, Gabriel; Loch, James T; Green, Oluyinka M; Kawatkar, Sameer P; Olivier, Nelson B; Boriack-Sjodin, P Ann; Keating, Thomas A

    2013-01-01

    Thymidylate kinase (TMK) is an essential enzyme for DNA synthesis in bacteria, phosphorylating deoxythymidine monophosphate (dTMP) to deoxythymidine diphosphate (dTDP), and thus is a potential new antibacterial drug target. Previously, we have described the first potent and selective inhibitors of Gram-positive TMK, leading to in vivo validation of the target. Here, a structure-guided design approach based on the initial series led to the discovery of novel sulfonylpiperidine inhibitors of TMK. Formation of hydrogen bonds with Arg48 in Staphylococcus aureus TMK was key to obtaining excellent enzyme affinity, as verified by protein crystallography. Replacement of a methylene linker in the series by a sulfonamide was accomplished with retention of binding conformation. Further optimization of logD yielded phenol derivative 11, a potent inhibitor of TMK showing excellent MICs against a broad spectrum of Gram-positive bacteria and >10(5) selectivity versus the human TMK homologue. PMID:23206863

  11. Evolution of resistance to Aurora kinase B inhibitors in leukaemia cells.

    Directory of Open Access Journals (Sweden)

    Timothy W Failes

    Full Text Available Aurora kinase inhibitors are new mitosis-targeting drugs currently in clinical trials for the treatment of haematological and solid malignancies. However, knowledge of the molecular factors that influence sensitivity and resistance remains limited. Herein, we developed and characterised an in vitro leukaemia model of resistance to the Aurora B inhibitor ZM447439. Human T-cell acute lymphoblastic leukaemia cells, CCRF-CEM, were selected for resistance in 4 µM ZM447439. CEM/AKB4 cells showed no cross-resistance to tubulin-targeted and DNA-damaging agents, but were hypersensitive to an Aurora kinase A inhibitor. Sequencing revealed a mutation in the Aurora B kinase domain corresponding to a G160E amino acid substitution. Molecular modelling of drug binding in Aurora B containing this mutation suggested that resistance is mediated by the glutamate substitution preventing formation of an active drug-binding motif. Progression of resistance in the more highly selected CEM/AKB8 and CEM/AKB16 cells, derived sequentially from CEM/AKB4 in 8 and 16 µM ZM447439 respectively, was mediated by additional defects. These defects were independent of Aurora B and multi-drug resistance pathways and are associated with reduced apoptosis mostly likely due to reduced inhibition of the catalytic activity of aurora kinase B in the presence of drug. Our findings are important in the context of the use of these new targeted agents in treatment regimes against leukaemia and suggest resistance to therapy may arise through multiple independent mechanisms.

  12. Characterization of the biological effects of a novel protein kinase D inhibitor in endothelial cells.

    Science.gov (United States)

    Evans, Ian M; Bagherzadeh, Azadeh; Charles, Mark; Raynham, Tony; Ireson, Chris; Boakes, Alexandra; Kelland, Lloyd; Zachary, Ian C

    2010-08-01

    VEGF (vascular endothelial growth factor) plays an essential role in angiogenesis during development and in disease largely mediated by signalling events initiated by binding of VEGF to its receptor, VEGFR2 (VEGF receptor 2)/KDR (kinase insert domain receptor). Recent studies indicate that VEGF activates PKD (protein kinase D) in endothelial cells to regulate a variety of cellular functions, including signalling events, proliferation, migration and angiogenesis. To better understand the role of PKD in VEGF-mediated endothelial function, we characterized the effects of a novel pyrazine benzamide PKD inhibitor CRT5 in HUVECs (human umbilical vein endothelial cells). The activity of the isoforms PKD1 and PKD2 were blocked by this inhibitor as indicated by reduced phosphorylation, at Ser916 and Ser876 respectively, after VEGF stimulation. The VEGF-induced phosphorylation of three PKD substrates, histone deacetylase 5, CREB (cAMP-response-element-binding protein) and HSP27 (heat-shock protein 27) at Ser82, was also inhibited by CRT5. In contrast, CRT6, an inactive analogue of CRT5, had no effect on PKD or HSP27 Ser82 phosphorylation. Furthermore, phosphorylation of HSP27 at Ser78, which occurs solely via the p38 MAPK (mitogen-activated protein kinase) pathway, was also unaffected by CRT5. In vitro kinase assays show that CRT5 did not significantly inhibit several PKC isoforms expressed in endothelial cells. CRT5 also decreased VEGF-induced endothelial migration, proliferation and tubulogenesis, similar to effects seen when the cells were transfected with PKD siRNA (small interfering RNA). CRT5, a novel specific PKD inhibitor, will greatly facilitate the study of the role of PKD signalling mechanisms in angiogenesis. PMID:20497126

  13. The potent Cdc7-Dbf4 (DDK) kinase inhibitor XL413 has limited activity in many cancer cell lines and discovery of potential new DDK inhibitor scaffolds.

    Science.gov (United States)

    Sasi, Nanda Kumar; Tiwari, Kanchan; Soon, Fen-Fen; Bonte, Dorine; Wang, Tong; Melcher, Karsten; Xu, H Eric; Weinreich, Michael

    2014-01-01

    Cdc7-Dbf4 kinase or DDK (Dbf4-dependent kinase) is required to initiate DNA replication by phosphorylating and activating the replicative Mcm2-7 DNA helicase. DDK is overexpressed in many tumor cells and is an emerging chemotherapeutic target since DDK inhibition causes apoptosis of diverse cancer cell types but not of normal cells. PHA-767491 and XL413 are among a number of potent DDK inhibitors with low nanomolar IC50 values against the purified kinase. Although XL413 is highly selective for DDK, its activity has not been extensively characterized on cell lines. We measured anti-proliferative and apoptotic effects of XL413 on a panel of tumor cell lines compared to PHA-767491, whose activity is well characterized. Both compounds were effective biochemical DDK inhibitors but surprisingly, their activities in cell lines were highly divergent. Unlike PHA-767491, XL413 had significant anti-proliferative activity against only one of the ten cell lines tested. Since XL413 did not effectively inhibit DDK in multiple cell lines, this compound likely has limited bioavailability. To identify potential leads for additional DDK inhibitors, we also tested the cross-reactivity of ∼400 known kinase inhibitors against DDK using a DDK thermal stability shift assay (TSA). We identified 11 compounds that significantly stabilized DDK. Several inhibited DDK with comparable potency to PHA-767491, including Chk1 and PKR kinase inhibitors, but had divergent chemical scaffolds from known DDK inhibitors. Taken together, these data show that several well-known kinase inhibitors cross-react with DDK and also highlight the opportunity to design additional specific, biologically active DDK inhibitors for use as chemotherapeutic agents.

  14. The potent Cdc7-Dbf4 (DDK kinase inhibitor XL413 has limited activity in many cancer cell lines and discovery of potential new DDK inhibitor scaffolds.

    Directory of Open Access Journals (Sweden)

    Nanda Kumar Sasi

    Full Text Available Cdc7-Dbf4 kinase or DDK (Dbf4-dependent kinase is required to initiate DNA replication by phosphorylating and activating the replicative Mcm2-7 DNA helicase. DDK is overexpressed in many tumor cells and is an emerging chemotherapeutic target since DDK inhibition causes apoptosis of diverse cancer cell types but not of normal cells. PHA-767491 and XL413 are among a number of potent DDK inhibitors with low nanomolar IC50 values against the purified kinase. Although XL413 is highly selective for DDK, its activity has not been extensively characterized on cell lines. We measured anti-proliferative and apoptotic effects of XL413 on a panel of tumor cell lines compared to PHA-767491, whose activity is well characterized. Both compounds were effective biochemical DDK inhibitors but surprisingly, their activities in cell lines were highly divergent. Unlike PHA-767491, XL413 had significant anti-proliferative activity against only one of the ten cell lines tested. Since XL413 did not effectively inhibit DDK in multiple cell lines, this compound likely has limited bioavailability. To identify potential leads for additional DDK inhibitors, we also tested the cross-reactivity of ∼400 known kinase inhibitors against DDK using a DDK thermal stability shift assay (TSA. We identified 11 compounds that significantly stabilized DDK. Several inhibited DDK with comparable potency to PHA-767491, including Chk1 and PKR kinase inhibitors, but had divergent chemical scaffolds from known DDK inhibitors. Taken together, these data show that several well-known kinase inhibitors cross-react with DDK and also highlight the opportunity to design additional specific, biologically active DDK inhibitors for use as chemotherapeutic agents.

  15. Comparison of the cancer gene targeting and biochemical selectivities of all targeted kinase inhibitors approved for clinical use.

    Directory of Open Access Journals (Sweden)

    Joost C M Uitdehaag

    Full Text Available The anti-proliferative activities of all twenty-five targeted kinase inhibitor drugs that are in clinical use were measured in two large assay panels: (1 a panel of proliferation assays of forty-four human cancer cell lines from diverse tumour tissue origins; and (2 a panel of more than 300 kinase enzyme activity assays. This study provides a head-on comparison of all kinase inhibitor drugs in use (status Nov. 2013, and for six of these drugs, the first kinome profiling data in the public domain. Correlation of drug activities with cancer gene mutations revealed novel drug sensitivity markers, suggesting that cancers dependent on mutant CTNNB1 will respond to trametinib and other MEK inhibitors, and cancers dependent on SMAD4 to small molecule EGFR inhibitor drugs. Comparison of cellular targeting efficacies reveals the most targeted inhibitors for EGFR, ABL1 and BRAF(V600E-driven cell growth, and demonstrates that the best targeted agents combine high biochemical potency with good selectivity. For ABL1 inhibitors, we computationally deduce optimized kinase profiles for use in a next generation of drugs. Our study shows the power of combining biochemical and cellular profiling data in the evaluation of kinase inhibitor drug action.

  16. The relative expression of Mig6 and EGFR is associated with resistance to EGFR kinase inhibitors.

    Directory of Open Access Journals (Sweden)

    Xiaofei Chang

    Full Text Available The sensitivity of only a few tumors to anti-epidermal growth factor receptor EGFR tyrosine kinase inhibitors (TKIs can be explained by the presence of EGFR tyrosine kinase (TK domain mutations. In addition, such mutations were rarely found in tumor types other than lung, such as pancreatic and head and neck cancer. In this study we sought to elucidate mechanisms of resistance to EGFR-targeted therapies in tumors that do not harbor TK sensitizing mutations in order to identify markers capable of guiding the decision to incorporate these drugs into chemotherapeutic regimens. Here we show that EGFR activity was markedly decreased during the evolution of resistance to the EGFR tyrosine kinase inhibitor (TKI erlotinib, with a concomitant increase of mitogen-inducible gene 6 (Mig6, a negative regulator of EGFR through the upregulation of the PI3K-AKT pathway. EGFR activity, which was more accurately predicted by the ratio of Mig6/EGFR, highly correlated with erlotinib sensitivity in panels of cancer cell lines of different tissue origins. Blinded testing and analysis in a prospectively followed cohort of lung cancer patients treated with gefitinib alone demonstrated higher response rates and a marked increased in progression free survival for patients with a low Mig6/EGFR ratio (approximately 100 days, P = 0.01.

  17. Manganese-induced integrin affinity maturation promotes recruitment of alpha V beta 3 integrin to focal adhesions in endothelial cells: evidence for a role of phosphatidylinositol 3-kinase and Src.

    Science.gov (United States)

    Dormond, Olivier; Ponsonnet, Lionel; Hasmim, Meriem; Foletti, Alessandro; Rüegg, Curzio

    2004-07-01

    Integrin activity is controlled by changes in affinity (i.e. ligand binding) and avidity (i.e. receptor clustering). Little is known, however, about the effect of affinity maturation on integrin avidity and on the associated signaling pathways. To study the effect of affinity maturation on integrin avidity, we stimulated human umbilical vein endothelial cells (HUVEC) with MnCl(2) to increase integrin affinity and monitored clustering of beta 1 and beta 3 integrins. In unstimulated HUVEC, beta 1 integrins were present in fibrillar adhesions, while alpha V beta 3 was detected in peripheral focal adhesions. Clustered beta 1 and beta 3 integrins expressed high affinity/ligand-induced binding site (LIBS) epitopes. MnCl(2)-stimulation promoted focal adhesion and actin stress fiber formation at the basal surface of the cells, and strongly enhanced mAb LM609 staining and expression of beta 3 high affinity/LIBS epitopes at focal adhesions. MnCl(2)-induced alpha V beta 3 clustering was blocked by a soluble RGD peptide, by wortmannin and LY294002, two pharmacological inhibitors of phosphatidylinositol 3-kinase (PI 3-K), and by over-expressing a dominant negative PI 3-K mutant protein. Conversely, over-expression of active PI 3-K and pharmacological inhibiton of Src with PP2 and CGP77675, enhanced basal and manganese-induced alpha V beta 3 clustering. Transient increased phosphorylation of protein kinase B/Akt, a direct target of PI 3K, occurred upon manganese stimulation. MnCl(2) did not alter beta 1 integrin distribution or beta1 high-affinity/LIBS epitope expression. Based on these results, we conclude that MnCl(2)-induced alpha V beta 3 integrin affinity maturation stimulates focal adhesion and actin stress fiber formation, and promotes recruitment of high affinity alpha V beta 3 to focal adhesions. Affinity-modulated alpha V beta 3 clustering requires PI3-K signaling and is negatively regulate by Src.

  18. Determination of human serum alpha1-acid glycoprotein and albumin binding of various marketed and preclinical kinase inhibitors.

    Science.gov (United States)

    Zsila, Ferenc; Fitos, Ilona; Bencze, Gyula; Kéri, György; Orfi, László

    2009-01-01

    There are about 380 protein kinase inhibitors in drug development as of today and 15 drugs have been marketed already for the treatment of cancer. This time 139 validated kinase targets are in the focus of drug research of pharmaceutical companies and big efforts are made for the development of new, druglike kinase inhibitors. Plasma protein binding is an important factor of the ADME profiling of a drug compound. Human serum albumin (HSA) and alpha(1)-acid glycoprotein (AAG) are the most relevant drug carriers in blood plasma. Since previous literature data indicated that AAG is the principal plasma binding component of some kinase inhibitors the present work focuses on the comprehensive evaluation of AAG binding of a series of marketed and experimental kinase inhibitors by using circular dichroism (CD) spectroscopy approach. HSA binding was also evaluated by affinity chromatography. Protein binding interactions of twenty-six kinase inhibitors are characterized. The contribution of AAG and HSA binding data to the pharmacokinetic profiles of the investigated therapeutic agents is discussed. Structural, biological and drug binding properties of AAG as well as the applicability of the CD method in studying drug-protein binding interactions are also briefly reviewed.

  19. Design of a selective insulin receptor tyrosine kinase inhibitor and its effect on glucose uptake and metabolism in intact cells

    International Nuclear Information System (INIS)

    An inhibitor of the insulin receptor tyrosine kinase (IRTK), (hydroxy-2-napthalenylmethyl)phosphonic acid, was designed and synthesized and was shown to be an inhibitor of the biological effects of insulin in vitro. With a wheat germ purified human placental insulin receptor preparation, this compound inhibited the insulin-stimulated autophosphorylation of the 95-kDa β-subunit of the insulin receptor. The ability of the kinase to phosphorylate an exogenous peptide substrate, angiotensin II, was also inhibited. Half-maximal inhibition of basal and insulin-stimulated human placental IRTK activity was found at concentrations of 150 and 100 μM, respectively, with 2 mM angiotensin II as the peptide substrate. The inhibitor was found to be specific for tyrosine kinases over serine kinases and noncompetitive with ATP. The inhibitor was converted into various (acyloxy)methyl prodrugs in order to achieve permeability through cell membranes. These prodrugs inhibited insulin-stimulated autophosphorylation of the insulin receptor 95-kDa β-subunit in intact CHO cells transfected with human insulin receptor. Inhibition of insulin-stimulated glucose oxidation in isolated rat adipocytes and 2-deoxyglucose uptake into CHO cells was observed with these prodrugs. The data provide additional evidence for the involvement of the insulin receptor tyrosine kinase in the regulation of glucose uptake and metabolism. These results and additional data reported herein suggest that this class of prodrugs and inhibitors will be useful for modulating the activity of a variety of tyrosine kinases

  20. Adhesion-related kinase induction of migration requires phosphatidylinositol-3-kinase and ras stimulation of rac activity in immortalized gonadotropin-releasing hormone neuronal cells.

    Science.gov (United States)

    Nielsen-Preiss, Sheila M; Allen, Melissa P; Xu, Mei; Linseman, Daniel A; Pawlowski, John E; Bouchard, R J; Varnum, Brian C; Heidenreich, Kim A; Wierman, Margaret E

    2007-06-01

    GnRH neurons migrate into the hypothalamus during development. Although migratory defects may result in disordered activation of the reproductive axis and lead to delayed or absent sexual maturation, specific factors regulating GnRH neuronal migration remain largely unknown. The receptor tyrosine kinase, adhesion-related kinase (Ark) (also known as Axl, UFO, and Tyro7), has been implicated in the migration of GnRH neuronal cells. Binding of its ligand, growth arrest-specific gene 6 (Gas6), promotes cytoskeletal remodeling and migration of NLT GnRH neuronal cells via Rac and p38 MAPK. Here, we examined the Axl effectors proximal to Rac in the signaling pathway. Gas6/Axl-induced lamellipodia formation and migration were blocked after phosphatidylinositol-3-kinase (PI3K) inhibition in GnRH neuronal cells. The p85 subunit of PI3K coimmunoprecipitated with Axl and was phosphorylated in a Gas6-sensitive manner. In addition, PI3K inhibition in GnRH neuronal cells diminished Gas6-induced Rac activation. Exogenous expression of a dominant-negative form of Ras also decreased GnRH neuronal lamellipodia formation, migration, and Rac activation. PI3K inhibition blocked Ras in addition to Rac activation and migration. In contrast, pharmacological blockade of the phospholipase C gamma effectors, protein kinase C or calcium/calmodulin protein kinase II, had no effect on Gas6/Axl signaling to promote Rac activation or stimulate cytoskeletal reorganization and migration. Together, these data show that the PI3K-Ras pathway is a major mediator of Axl actions upstream of Rac to induce GnRH neuronal cell migration. PMID:17332061

  1. Erkitinib, a novel EGFR tyrosine kinase inhibitor screened using a ProteoChip system from a phytochemical library

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eung-Yoon; Choi, Young-Jin [Biochip Research Center, Hoseo University, Asan 336-795 (Korea, Republic of); Innopharmascreen, Inc., Asan 336-795 (Korea, Republic of); Park, Chan-Won [Biochip Research Center, Hoseo University, Asan 336-795 (Korea, Republic of); Dept. of Biological Science, Hoseo University, Asan 336-795 (Korea, Republic of); Kang, In-Cheol, E-mail: ickang@hoseo.edu [Biochip Research Center, Hoseo University, Asan 336-795 (Korea, Republic of); Dept. of Biological Science, Hoseo University, Asan 336-795 (Korea, Republic of); Innopharmascreen, Inc., Asan 336-795 (Korea, Republic of)

    2009-11-20

    Receptor tyrosine kinases (PTKs) play key roles in the pathogenesis of numerous human diseases, including cancer. Therefore PTK inhibitors are currently under intensive investigation as potential drug candidates. Herein, we report on a ProteoChip-based screening of an epidermal growth factor receptor (EGFR) tyrosine kinase (TK) inhibitor, Erkitinibs, from phytochemical libraries. PLC-{gamma}-1 was used as a substrate immobilized on a ProteoChip and incubated with an EGFR kinase to phosphorylate tyrosine residues of the substrate, followed by a fluorescence detection of the substrate recognized by a phospho-specific monoclonal antibody. Erkitinibs inhibited HeLa cell proliferation in a dose-dependent manner. In conclusion, these data suggest that Erkitinibs can be a specific inhibitor of an EGFR kinase and can be further developed as a potent anti-tumor agent.

  2. Activation of AMP-activated protein kinase attenuates hepatocellular carcinoma cell adhesion stimulated by adipokine resistin

    OpenAIRE

    Yang, Chen-Chieh; Chang, Shun-Fu; Chao, Jian-Kang; Lai, Yi-Liang; Chang, Wei-En; Hsu, Wen-Hsiu; Kuo, Wu-Hsien

    2014-01-01

    Background Resistin, adipocyte-secreting adipokine, may play critical role in modulating cancer pathogenesis. The aim of this study was to investigate the effects of resistin on HCC adhesion to the endothelium, and the mechanism underlying these resistin effects. Methods Human SK-Hep1 cells were used to study the effect of resistin on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions as well as NF-κB activation, and hence cell adhesion to hu...

  3. QSAR based docking studies of marine algal anticancer compounds as inhibitors of protein kinase B (PKBβ).

    Science.gov (United States)

    Davis, G Dicky John; Vasanthi, A Hannah Rachel

    2015-08-30

    Marine algae are prolific source of bioactive secondary metabolites and are found to be active against different cancer cell lines. QSAR studies will explicate the significance of a particular class of descriptor in eliciting anticancer activity against a cancer type. Marine algal compounds showing anticancer activity against six different cancer cell lines namely MCF-7, A431, HeLa, HT-29, P388 and A549 taken from Seaweed metabolite database were subjected to comprehensive QSAR modeling studies. A hybrid-GA (genetic algorithm) optimization technique for descriptor space reduction and multiple linear regression analysis (MLR) approach was used as fitness functions. Cell lines HeLa and MCF-7 showed good statistical quality (R(2)∼0.75, Q(2)∼0.65) followed by A431, HT29 and P388 cell lines with reasonable statistical values (R(2)∼0.70, Q(2)∼0.60). The models developed were interpretable, with good statistical and predictive significance. Molecular descriptor analyses revealed that Baumann's alignment-independent topological descriptors had a major role in variation of activity along with other descriptors. Incidentally, earlier QSAR analysis on a variety of chemically diverse PKBα inhibitors revealed Baumann's alignment-independent topological descriptors that differentiated the molecules binding to Protein kinase B (PKBα) kinase or PH domain, hence a docking study of two crystal structures of PKBβ was performed for identification of novel ATP-competitive inhibitors of PKBβ. Five compounds had a good docking score and Callophycin A showed better ligand efficiency than other PKBβ inhibitors. Furthermore in silico pharmacokinetic and toxicity studies also showed that Callophycin A had a high drug score (0.85) compared to the other inhibitors. These results encourages discovering novel inhibitors for cancer therapeutic targets by screening metabolites from marine algae.

  4. Molecular docking and NMR binding studies to identify novel inhibitors of human phosphomevalonate kinase

    Energy Technology Data Exchange (ETDEWEB)

    Boonsri, Pornthip [Chemical Proteomics Facility at Marquette, Department of Chemistry, Marquette University, Milwaukee, WI 53201 (United States); Department of Chemistry, NANOTEC Center of Nanotechnology, National Nanotechnology Center, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand); Neumann, Terrence S.; Olson, Andrew L.; Cai, Sheng [Chemical Proteomics Facility at Marquette, Department of Chemistry, Marquette University, Milwaukee, WI 53201 (United States); Herdendorf, Timothy J.; Miziorko, Henry M. [Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110 (United States); Hannongbua, Supa [Department of Chemistry, NANOTEC Center of Nanotechnology, National Nanotechnology Center, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand); Sem, Daniel S., E-mail: daniel.sem@cuw.edu [Chemical Proteomics Facility at Marquette, Department of Chemistry, Marquette University, Milwaukee, WI 53201 (United States)

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer Natural and synthetic inhibitors of human phosphomevalonate kinase identified. Black-Right-Pointing-Pointer Virtual screening yielded a hit rate of 15%, with inhibitor K{sub d}'s of 10-60 {mu}M. Black-Right-Pointing-Pointer NMR studies indicate significant protein conformational changes upon binding. -- Abstract: Phosphomevalonate kinase (PMK) phosphorylates mevalonate-5-phosphate (M5P) in the mevalonate pathway, which is the sole source of isoprenoids and steroids in humans. We have identified new PMK inhibitors with virtual screening, using autodock. Promising hits were verified and their affinity measured using NMR-based {sup 1}H-{sup 15}N heteronuclear single quantum coherence (HSQC) chemical shift perturbation and fluorescence titrations. Chemical shift changes were monitored, plotted, and fitted to obtain dissociation constants (K{sub d}). Tight binding compounds with K{sub d}'s ranging from 6-60 {mu}M were identified. These compounds tended to have significant polarity and negative charge, similar to the natural substrates (M5P and ATP). HSQC cross peak changes suggest that binding induces a global conformational change, such as domain closure. Compounds identified in this study serve as chemical genetic probes of human PMK, to explore pharmacology of the mevalonate pathway, as well as starting points for further drug development.

  5. Mutations in G protein beta subunits promote transformation and kinase inhibitor resistance

    Science.gov (United States)

    Yoda, Akinori; Adelmant, Guillaume; Tamburini, Jerome; Chapuy, Bjoern; Shindoh, Nobuaki; Yoda, Yuka; Weigert, Oliver; Kopp, Nadja; Wu, Shuo-Chieh; Kim, Sunhee S.; Liu, Huiyun; Tivey, Trevor; Christie, Amanda L.; Elpek, Kutlu G.; Card, Joseph; Gritsman, Kira; Gotlib, Jason; Deininger, Michael W.; Makishima, Hideki; Turley, Shannon J.; Javidi-Sharifi, Nathalie; Maciejewski, Jaroslaw P.; Jaiswal, Siddhartha; Ebert, Benjamin L.; Rodig, Scott J.; Tyner, Jeffrey W.; Marto, Jarrod A.; Weinstock, David M.; Lane, Andrew A.

    2014-01-01

    Activating mutations of G protein alpha subunits (Gα) occur in 4–5% of all human cancers1 but oncogenic alterations in beta subunits (Gβ) have not been defined. Here we demonstrate that recurrent mutations in the Gβ proteins GNB1 and GNB2 confer cytokine-independent growth and activate canonical G protein signaling. Multiple mutations in GNB1 affect the protein interface that binds Gα subunits as well as downstream effectors, and disrupt Gα-Gβγ interactions. Different mutations in Gβ proteins clustered to some extent based on lineage; for example, all eleven GNB1 K57 mutations were in myeloid neoplasms while 7 of 8 GNB1 I80 mutations were in B cell neoplasms. Expression of patient-derived GNB1 alleles in Cdkn2a-deficient bone marrow followed by transplantation resulted in either myeloid or B cell malignancies. In vivo treatment with the dual PI3K/mTOR inhibitor BEZ235 suppressed GNB1-induced signaling and markedly increased survival. In several human tumors, GNB1 mutations co-occurred with oncogenic kinase alterations, including BCR/ABL, JAK2 V617F and BRAF V600K. Co-expression of patient-derived GNB1 alleles with these mutant kinases resulted in inhibitor resistance in each context. Thus, GNB1 and GNB2 mutations confer transformed and resistance phenotypes across a range of human tumors and may be targetable with inhibitors of G protein signaling. PMID:25485910

  6. De novo design of protein kinase inhibitors by in silico identification of hinge region-binding fragments.

    Science.gov (United States)

    Urich, Robert; Wishart, Grant; Kiczun, Michael; Richters, André; Tidten-Luksch, Naomi; Rauh, Daniel; Sherborne, Brad; Wyatt, Paul G; Brenk, Ruth

    2013-05-17

    Protein kinases constitute an attractive family of enzyme targets with high relevance to cell and disease biology. Small molecule inhibitors are powerful tools to dissect and elucidate the function of kinases in chemical biology research and to serve as potential starting points for drug discovery. However, the discovery and development of novel inhibitors remains challenging. Here, we describe a structure-based de novo design approach that generates novel, hinge-binding fragments that are synthetically feasible and can be elaborated to small molecule libraries. Starting from commercially available compounds, core fragments were extracted, filtered for pharmacophoric properties compatible with hinge-region binding, and docked into a panel of protein kinases. Fragments with a high consensus score were subsequently short-listed for synthesis. Application of this strategy led to a number of core fragments with no previously reported activity against kinases. Small libraries around the core fragments were synthesized, and representative compounds were tested against a large panel of protein kinases and subjected to co-crystallization experiments. Each of the tested compounds was active against at least one kinase, but not all kinases in the panel were inhibited. A number of compounds showed high ligand efficiencies for therapeutically relevant kinases; among them were MAPKAP-K3, SRPK1, SGK1, TAK1, and GCK for which only few inhibitors are reported in the literature.

  7. Small Molecule Tyrosine Kinase Inhibitors of ErbB2/HER2/Neu in the Treatment of Aggressive Breast Cancer

    Directory of Open Access Journals (Sweden)

    Richard L. Schroeder

    2014-09-01

    Full Text Available The human epidermal growth factor receptor 2 (HER2 is a member of the erbB class of tyrosine kinase receptors. These proteins are normally expressed at the surface of healthy cells and play critical roles in the signal transduction cascade in a myriad of biochemical pathways responsible for cell growth and differentiation. However, it is widely known that amplification and subsequent overexpression of the HER2 encoding oncogene results in unregulated cell proliferation in an aggressive form of breast cancer known as HER2-positive breast cancer. Existing therapies such as trastuzumab (Herceptin® and lapatinib (Tyverb/Tykerb®, a monoclonal antibody inhibitor and a dual EGFR/HER2 kinase inhibitor, respectively, are currently used in the treatment of HER2-positive cancers, although issues with high recurrence and acquired resistance still remain. Small molecule tyrosine kinase inhibitors provide attractive therapeutic targets, as they are able to block cell signaling associated with many of the proposed mechanisms for HER2 resistance. In this regard we aim to present a review on the available HER2 tyrosine kinase inhibitors, as well as those currently in development. The use of tyrosine kinase inhibitors as sequential or combinatorial therapeutic strategies with other HER family inhibitors is also discussed.

  8. Metformin is an AMP kinase-dependent growth inhibitor for breast cancer cells.

    Science.gov (United States)

    Zakikhani, Mahvash; Dowling, Ryan; Fantus, I George; Sonenberg, Nahum; Pollak, Michael

    2006-11-01

    Recent population studies provide clues that the use of metformin may be associated with reduced incidence and improved prognosis of certain cancers. This drug is widely used in the treatment of type 2 diabetes, where it is often referred to as an "insulin sensitizer" because it not only lowers blood glucose but also reduces the hyperinsulinemia associated with insulin resistance. As insulin and insulin-like growth factors stimulate proliferation of many normal and transformed cell types, agents that facilitate signaling through these receptors would be expected to enhance proliferation. We show here that metformin acts as a growth inhibitor rather than an insulin sensitizer for epithelial cells. Breast cancer cells can be protected against metformin-induced growth inhibition by small interfering RNA against AMP kinase. This shows that AMP kinase pathway activation by metformin, recently shown to be necessary for metformin inhibition of gluconeogenesis in hepatocytes, is also involved in metformin-induced growth inhibition of epithelial cells. The growth inhibition was associated with decreased mammalian target of rapamycin and S6 kinase activation and a general decrease in mRNA translation. These results provide evidence for a mechanism that may contribute to the antineoplastic effects of metformin suggested by recent population studies and justify further work to explore potential roles for activators of AMP kinase in cancer prevention and treatment. PMID:17062558

  9. Inhibitor of apoptosis signal-regulating kinase 1 protects against acetaminophen-induced liver injury

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yuchao; Ramachandran, Anup [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Breckenridge, David G.; Liles, John T. [Department of Biology, Gilead Sciences, Inc., Foster City, CA (United States); Lebofsky, Margitta [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Farhood, Anwar [Department of Pathology, St. David' s North Austin Medical Center, Austin, TX 78756 (United States); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2015-07-01

    Metabolic activation and oxidant stress are key events in the pathophysiology of acetaminophen (APAP) hepatotoxicity. The initial mitochondrial oxidative stress triggered by protein adduct formation is amplified by c-jun-N-terminal kinase (JNK), resulting in mitochondrial dysfunction and ultimately cell necrosis. Apoptosis signal-regulating kinase 1 (ASK1) is considered the link between oxidant stress and JNK activation. The objective of the current study was to assess the efficacy and mechanism of action of the small-molecule ASK1 inhibitor GS-459679 in a murine model of APAP hepatotoxicity. APAP (300 mg/kg) caused extensive glutathione depletion, JNK activation and translocation to the mitochondria, oxidant stress and liver injury as indicated by plasma ALT activities and area of necrosis over a 24 h observation period. Pretreatment with 30 mg/kg of GS-459679 almost completely prevented JNK activation, oxidant stress and injury without affecting the metabolic activation of APAP. To evaluate the therapeutic potential of GS-459679, mice were treated with APAP and then with the inhibitor. Given 1.5 h after APAP, GS-459679 was still protective, which was paralleled by reduced JNK activation and p-JNK translocation to mitochondria. However, GS-459679 treatment was not more effective than N-acetylcysteine, and the combination of GS-459679 and N-acetylcysteine exhibited similar efficacy as N-acetylcysteine monotherapy, suggesting that GS-459769 and N-acetylcysteine affect the same pathway. Importantly, inhibition of ASK1 did not impair liver regeneration as indicated by PCNA staining. In conclusion, the ASK1 inhibitor GS-459679 protected against APAP toxicity by attenuating JNK activation and oxidant stress in mice and may have therapeutic potential for APAP overdose patients. - Highlights: • Two ASK1 inhibitors protected against acetaminophen-induced liver injury. • The ASK1 inhibitors protect when used as pre- or post-treatment. • Protection by ASK1 inhibitor is

  10. Focal adhesion kinase: predictor of tumour response and risk factor for recurrence after neoadjuvant chemoradiation in rectal cancer.

    Science.gov (United States)

    Gómez Del Pulgar, Teresa; Cebrián, Arancha; Fernández-Aceñero, Maria Jesús; Borrero-Palacios, Aurea; Del Puerto-Nevado, Laura; Martínez-Useros, Javier; Marín-Arango, Juan Pablo; Caramés, Cristina; Vega-Bravo, Ricardo; Rodríguez-Remírez, María; Cruz-Ramos, Marlid; Manzarbeitia, Félix; García-Foncillas, Jesús

    2016-09-01

    Rectal cancer represents about 30% of colorectal cancers, being around 50% locally advanced at presentation. Chemoradiation (CRT) followed by total mesorectal excision is the standard of care for these locally advanced stages. However, it is not free of adverse effects and toxicity and the complete pathologic response rate is between 10% and 30%. This makes it extremely important to define factors that can predict response to this therapy. Focal adhesion kinase (FAK) expression has been correlated with worse prognosis in several tumours and its possible involvement in cancer radio- and chemosensitivity has been suggested; however, its role in rectal cancer has not been analysed yet. To analyse the association of FAK expression with tumour response to CRT in locally advanced rectal cancer. This study includes 73 patients with locally advanced rectal cancer receiving standard neoadjuvant CRT followed by total mesorectal excision. Focal adhesion kinase protein levels were immunohistochemically analysed in the pre-treatment biopsies of these patients and correlated with tumour response to CRT and patients survival. Low FAK expression was significantly correlated with local and distant recurrence (P = 0.013). Low FAK expression was found to be a predictive marker of tumour response to neoadjuvant therapy (P = 0.007) and patients whose tumours did not express FAK showed a strong association with lower disease-free survival (P = 0.01). Focal adhesion kinase expression predicts neoadjuvant CRT response in rectal cancer patients and it is a clinically relevant risk factor for local and distant recurrence. PMID:27171907

  11. HER2-targeted therapy in breast cancer. Monoclonal antibodies and tyrosine kinase inhibitors

    DEFF Research Database (Denmark)

    Nielsen, Dorte Lisbet; Andersson, Michael; Kamby, Claus

    2008-01-01

    There is strong clinical evidence that trastuzumab, a monoclonal antibody targeting the human epidermal growth factor receptor (HER) two tyrosine kinase receptor, is an important component of first-line treatment of patients with HER2-positive metastatic breast cancer. In particular the combination...... with taxanes and vinorelbine has been established. In the preoperative setting inclusion of trastuzumab has significantly increased the pathological complete response rate. Results from large phase III trials evaluating adjuvant therapy in HER2-positive early breast cancer indicate that the addition...... of trastuzumab to chemotherapy improves disease-free and overall survival. The use of lapatinib, a dual tyrosine kinase inhibitor of both HER1 and HER2, in combination with capecitabine in the second-line treatment of HER2-positive patients with metastatic breast cancer previously treated with trastuzumab has...

  12. How tyrosine kinase inhibitors impair metabolism and endocrine system function: a systematic updated review.

    Science.gov (United States)

    Breccia, Massimo; Molica, Matteo; Alimena, Giuliana

    2014-12-01

    Tyrosine kinase inhibitors (TKIs) advent has deeply changed the outcome of chronic myeloid leukemia (CML) patients, with improved rates of response and overall survival. However, for this success some patients paid the price of a number of peculiar side effects, the so-called off-target side effects, specific for each one TKI. These effects are due to non-selective inhibition of other tyrosine kinase receptors, such as PDGFR, c-KIT, Src, VEGF. Consequences of this inhibition, some metabolic changes during the treatment with TKIs are reported. Aim of present review is to report metabolic changes and potential mechanisms involved in the pathogenesis related to imatinib, second (nilotinib and dasatinib) and third generation (bosutinib and ponatinib) TKIs.

  13. Protein Kinase C Inhibitors as Modulators of Vascular Function and Their Application in Vascular Disease

    Directory of Open Access Journals (Sweden)

    Raouf A. Khalil

    2013-03-01

    Full Text Available Blood pressure (BP is regulated by multiple neuronal, hormonal, renal and vascular control mechanisms. Changes in signaling mechanisms in the endothelium, vascular smooth muscle (VSM and extracellular matrix cause alterations in vascular tone and blood vessel remodeling and may lead to persistent increases in vascular resistance and hypertension (HTN. In VSM, activation of surface receptors by vasoconstrictor stimuli causes an increase in intracellular free Ca2+ concentration ([Ca2+]i, which forms a complex with calmodulin, activates myosin light chain (MLC kinase and leads to MLC phosphorylation, actin-myosin interaction and VSM contraction. Vasoconstrictor agonists could also increase the production of diacylglycerol which activates protein kinase C (PKC. PKC is a family of Ca2+-dependent and Ca2+-independent isozymes that have different distributions in various blood vessels, and undergo translocation from the cytosol to the plasma membrane, cytoskeleton or the nucleus during cell activation. In VSM, PKC translocation to the cell surface may trigger a cascade of biochemical events leading to activation of mitogen-activated protein kinase (MAPK and MAPK kinase (MEK, a pathway that ultimately increases the myofilament force sensitivity to [Ca2+]i, and enhances actin-myosin interaction and VSM contraction. PKC translocation to the nucleus may induce transactivation of various genes and promote VSM growth and proliferation. PKC could also affect endothelium-derived relaxing and contracting factors as well as matrix metalloproteinases (MMPs in the extracellular matrix further affecting vascular reactivity and remodeling. In addition to vasoactive factors, reactive oxygen species, inflammatory cytokines and other metabolic factors could affect PKC activity. Increased PKC expression and activity have been observed in vascular disease and in certain forms of experimental and human HTN. Targeting of vascular PKC using PKC inhibitors may function in

  14. Switch control pocket inhibitors of p38-MAP kinase. Durable type II inhibitors that do not require binding into the canonical ATP hinge region

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Yu Mi; Clare, Michael; Ensinger, Carol L.; Hood, Molly M.; Lord, John W.; Lu, Wei-Ping; Miller, David F.; Patt, William C.; Smith, Bryan D.; Vogeti, Lakshminarayana; Kaufman, Michael D.; Petillo, Peter A.; Wise, Scott C.; Abendroth, Jan; Chun, Lawrence; Clark, Robin; Feese, Michael; Kim, Hidong; Stewart, Lance; Flynn, Daniel L. (Deciphera); (Emerald); (Cocrystal)

    2012-01-20

    Switch control pocket inhibitors of p38-alpha kinase are described. Durable type II inhibitors were designed which bind to arginines (Arg67 or Arg70) that function as key residues for mediating phospho-threonine 180 dependant conformational fluxing of p38-alpha from an inactive type II state to an active type I state. Binding to Arg70 in particular led to potent inhibitors, exemplified by DP-802, which also exhibited high kinase selectivity. Binding to Arg70 obviated the requirement for binding into the ATP Hinge region. X-ray crystallography revealed that DP-802 and analogs induce an enhanced type II conformation upon binding to either the unphosphorylated or the doubly phosphorylated form of p38-alpha kinase.

  15. Switch control pocket inhibitors of p38-MAP kinase. Durable type II inhibitors that do not require binding into the canonical ATP hinge region.

    Science.gov (United States)

    Ahn, Yu Mi; Clare, Michael; Ensinger, Carol L; Hood, Molly M; Lord, John W; Lu, Wei-Ping; Miller, David F; Patt, William C; Smith, Bryan D; Vogeti, Lakshminarayana; Kaufman, Michael D; Petillo, Peter A; Wise, Scott C; Abendroth, Jan; Chun, Lawrence; Clark, Robin; Feese, Michael; Kim, Hidong; Stewart, Lance; Flynn, Daniel L

    2010-10-01

    Switch control pocket inhibitors of p38-alpha kinase are described. Durable type II inhibitors were designed which bind to arginines (Arg67 or Arg70) that function as key residues for mediating phospho-threonine 180 dependant conformational fluxing of p38-alpha from an inactive type II state to an active type I state. Binding to Arg70 in particular led to potent inhibitors, exemplified by DP-802, which also exhibited high kinase selectivity. Binding to Arg70 obviated the requirement for binding into the ATP Hinge region. X-ray crystallography revealed that DP-802 and analogs induce an enhanced type II conformation upon binding to either the unphosphorylated or the doubly phosphorylated form of p38-alpha kinase.

  16. ALK kinase domain mutations in primary anaplastic large cell lymphoma: consequences on NPM-ALK activity and sensitivity to tyrosine kinase inhibitors.

    Directory of Open Access Journals (Sweden)

    Federica Lovisa

    Full Text Available ALK inhibitor crizotinib has shown potent antitumor activity in children with refractory Anaplastic Large Cell Lymphoma (ALCL and the opportunity to include ALK inhibitors in first-line therapies is oncoming. However, recent studies suggest that crizotinib-resistance mutations may emerge in ALCL patients. In the present study, we analyzed ALK kinase domain mutational status of 36 paediatric ALCL patients at diagnosis to identify point mutations and gene aberrations that could impact on NPM-ALK gene expression, activity and sensitivity to small-molecule inhibitors. Amplicon ultra-deep sequencing of ALK kinase domain detected 2 single point mutations, R335Q and R291Q, in 2 cases, 2 common deletions of exon 23 and 25 in all the patients, and 7 splicing-related INDELs in a variable number of them. The functional impact of missense mutations and INDELs was evaluated. Point mutations were shown to affect protein kinase activity, signalling output and drug sensitivity. INDELs, instead, generated kinase-dead variants with dominant negative effect on NPM-ALK kinase, in virtue of their capacity of forming non-functional heterocomplexes. Consistently, when co-expressed, INDELs increased crizotinib inhibitory activity on NPM-ALK signal processing, as demonstrated by the significant reduction of STAT3 phosphorylation. Functional changes in ALK kinase activity induced by both point mutations and structural rearrangements were resolved by molecular modelling and dynamic simulation analysis, providing novel insights into ALK kinase domain folding and regulation. Therefore, these data suggest that NPM-ALK pre-therapeutic mutations may be found at low frequency in ALCL patients. These mutations occur randomly within the ALK kinase domain and affect protein activity, while preserving responsiveness to crizotinib.

  17. ALK kinase domain mutations in primary anaplastic large cell lymphoma: consequences on NPM-ALK activity and sensitivity to tyrosine kinase inhibitors.

    Science.gov (United States)

    Lovisa, Federica; Cozza, Giorgio; Cristiani, Andrea; Cuzzolin, Alberto; Albiero, Alessandro; Mussolin, Lara; Pillon, Marta; Moro, Stefano; Basso, Giuseppe; Rosolen, Angelo; Bonvini, Paolo

    2015-01-01

    ALK inhibitor crizotinib has shown potent antitumor activity in children with refractory Anaplastic Large Cell Lymphoma (ALCL) and the opportunity to include ALK inhibitors in first-line therapies is oncoming. However, recent studies suggest that crizotinib-resistance mutations may emerge in ALCL patients. In the present study, we analyzed ALK kinase domain mutational status of 36 paediatric ALCL patients at diagnosis to identify point mutations and gene aberrations that could impact on NPM-ALK gene expression, activity and sensitivity to small-molecule inhibitors. Amplicon ultra-deep sequencing of ALK kinase domain detected 2 single point mutations, R335Q and R291Q, in 2 cases, 2 common deletions of exon 23 and 25 in all the patients, and 7 splicing-related INDELs in a variable number of them. The functional impact of missense mutations and INDELs was evaluated. Point mutations were shown to affect protein kinase activity, signalling output and drug sensitivity. INDELs, instead, generated kinase-dead variants with dominant negative effect on NPM-ALK kinase, in virtue of their capacity of forming non-functional heterocomplexes. Consistently, when co-expressed, INDELs increased crizotinib inhibitory activity on NPM-ALK signal processing, as demonstrated by the significant reduction of STAT3 phosphorylation. Functional changes in ALK kinase activity induced by both point mutations and structural rearrangements were resolved by molecular modelling and dynamic simulation analysis, providing novel insights into ALK kinase domain folding and regulation. Therefore, these data suggest that NPM-ALK pre-therapeutic mutations may be found at low frequency in ALCL patients. These mutations occur randomly within the ALK kinase domain and affect protein activity, while preserving responsiveness to crizotinib.

  18. Efficacy of HER2-targeted therapy in metastatic breast cancer. Monoclonal antibodies and tyrosine kinase inhibitors

    DEFF Research Database (Denmark)

    Nielsen, Dorte L; Kümler, Iben; Palshof, Jesper Andreas;

    2013-01-01

    Therapies targeting the human epidermal growth factor receptor (HER) 2 are effective in metastatic breast cancer (MBC). We review the efficacy of HER2-directed therapies, focussing on monoclonal antibodies and tyrosine kinase inhibitors targeting HER2 that have been tested in phase II-III studies...... to those obtained for capecitabine plus lapatinib (48%), continuing trastuzumab in combination with capecitabine (48%), pertuzumab plus trastuzumab (24%), and neratinib (24%). Strategies combining multiple HER2-directed therapies might yield additive or synergistic effects and lead to improved outcome...

  19. Challenges Associated with Tyrosine Kinase Inhibitor Therapy for Metastatic Thyroid Cancer

    Directory of Open Access Journals (Sweden)

    Maria E. Cabanillas

    2011-01-01

    Full Text Available Tyrosine kinase inhibitors (TKIs which target angiogenesis are promising treatments for patients with metastatic medullary and differentiated thyroid cancers. Sorafenib, sunitinib, and pazopanib are commercially available drugs which have been studied in these diseases. Vandetanib is the first drug approved in the United States for treatment of medullary thyroid cancer. These TKIs are used as chronic therapies, and therefore it is imperative to understand the adverse event profile in order to avoid excessive toxicity and maintain patients on therapy as long as it proves beneficial. Here we review common toxicities, management of these, and other challenging situations that arise when using TKIs in patients with thyroid cancer.

  20. Influence of protein kinase C inhibitor in phagocytosis activity toward Candida sp

    Directory of Open Access Journals (Sweden)

    Adiprayitno Adiprayitno

    2001-09-01

    Full Text Available Protein kinase C isoenzyme family that expresses in all of cells plays a pivotal role in the signal transduction pathway of a variety of hormones, cytokines, neurotransmitter, and growth factors. The immunity against Candida sp is mainly mediated and performed by the T cells and macrophages. The objective of this experiment is to know the influence the protein kinase C inhibitor - bisindolylmaleimides in phagocytosis activity toward Candida sp. The culture of peritoneal macrophage derived from BALB/c mice are treated with bisindolylmaleimides as a protein kinase C inhibitor concentration varied from 5 ng/ml to 100 ng/ml for as long as 10 minute. Then the Candida sp added is observed after every 30 minute for as long as 120 minute. As the experimental design is used the method of factorial and orthogonal polynomial. The data consisting the length of pseudopodia and the number of Candida sp which are phagocytosed are analyzed applying the Anova. One Way Anova to show the differences of each manipulation, the Two Way Anova to show the interaction of manipulations and the Student's t Test to show the differences with control. Statistical test show significant differences on the length of pseudopodia, and phagocytosed Candida sp, at different bisindolylmaleimides concentration (p<0.001 and different observed time (p<0.001. The data show a significant interaction between the bisindolylmaleimides concentration and observed time (p<0.001. The higher the bisindolylmaleimides concentration, the earlier the observed time, the much number the protein kinase C are going inactive and the shorter the length of pseudopodia or the lower the macrophages phagocytic activity toward Candida sp. The result of this experiment indicates that bisindolylmaleimides can inhibit the macrophage mobility and phagocytic activity toward Candida sp. Further experiment in protein kinase C, especially in macrophage, is suggested. (Med J Indones 2001; 10: 150

  1. Molecular Shape Analysis-Guided Virtual Screening Platform for Adenosine Kinase Inhibitors

    Science.gov (United States)

    Bhutoria, Savita; Das, Ballari; Ghoshal, Nanda

    2016-01-01

    We propose a new application of molecular shape descriptors in hierarchical selection during virtual screening (VS). Here, a structure-based pharmacophore and docking-guided VS protocol have been evolved to identify inhibitors against adenosine kinase (AK). The knowledge gained on the shape requirements has been extrapolated in classifying active and inactive molecules against this target. This classification enabled us to pick the appropriate ligand conformation in the binding site. We have suggested a set of hierarchical filters for VS, from a simple molecular shape analysis (MSA) descriptor-based recursive models to docking scores. This approach permits a systematic study to understand the importance of spatial requirements and limitations for inhibitors against AK. Finally, the guidelines on how to select compounds for AK to achieve success have been highlighted. The utility of this approach has been suggested by giving an example of database screening for plausible active compounds. PMID:27478367

  2. Molecular Shape Analysis-Guided Virtual Screening Platform for Adenosine Kinase Inhibitors.

    Science.gov (United States)

    Bhutoria, Savita; Das, Ballari; Ghoshal, Nanda

    2016-01-01

    We propose a new application of molecular shape descriptors in hierarchical selection during virtual screening (VS). Here, a structure-based pharmacophore and docking-guided VS protocol have been evolved to identify inhibitors against adenosine kinase (AK). The knowledge gained on the shape requirements has been extrapolated in classifying active and inactive molecules against this target. This classification enabled us to pick the appropriate ligand conformation in the binding site. We have suggested a set of hierarchical filters for VS, from a simple molecular shape analysis (MSA) descriptor-based recursive models to docking scores. This approach permits a systematic study to understand the importance of spatial requirements and limitations for inhibitors against AK. Finally, the guidelines on how to select compounds for AK to achieve success have been highlighted. The utility of this approach has been suggested by giving an example of database screening for plausible active compounds. PMID:27478367

  3. Capillary electrophoresis as a novel technique for screening natural flavonoids as kinase inhibitors.

    Science.gov (United States)

    Nehmé, Reine; Nehmé, Hala; Roux, Grégory; Destandau, Emilie; Claude, Bérengère; Morin, Philippe

    2013-11-29

    Capillary electrophoresis (CE) was used for the first time to evaluate the inhibition activity of aglycone flavonoids (such as quercetin and isorhamnetin) and some of their glycosylated derivatives toward human kinases. The cyclin-dependant kinase 5 (CDK5/p25) and the glycogen synthase kinase 3β (GSK3β) were chosen since they are very promising biological targets for developing treatments against neurodegenerative diseases and cancer. In a previous work, we developed an in-capillary kinase CE assay where the capillary was used as an enzymatic nanoreactor in which the kinase, its substrate, adenosine 5'-triphosphate (ATP) and its potential inhibitor were mixed by using transverse diffusion of laminar flow profiles (TDLFP). The product adenosine 5'-diphosphate (ADP) was then detected at 254nm and quantified. In this work, this assay was improved to reduce, for the first time, the dilution effect commonly observed with the TDLFP approach. Under the new conditions established herein, IC50 values for quercetin, kaempferol and flavopiridol were successfully obtained and were in the same order of magnitude of those reported in the literature using the conventional assay using radioactive (33)P-ATP. It was shown that aglycone flavonoids have an inhibition activity more important than their glycosylated derivatives. CE was also proved to be very efficient for evaluating inhibition activity of complex samples such as crude extracts of sea buckthorn (SBT) berries obtained by solvent-free microwave extraction (SFME). This novel approach to combine SFME technique to a CE-based enzymatic assay is very interesting for evaluating the biological activity of natural material in a fast, simple, economic (no use of neither fluorescent nor radiometric labels) and green (no organic solvents) manner. PMID:24148298

  4. The endogenous inhibitor of protein kinase-C in the rat ovary is a protein phosphatase.

    Science.gov (United States)

    Eyster, K M; Waller, M S; Miller, T L; Miller, C J; Johnson, M J; Persing, J S

    1993-09-01

    Calcium- and lipid-dependent protein kinase (PKC) activity in the ovary of the pseudopregnant rat is masked by an endogenous inhibitor of PKC. These studies were undertaken to examine the mechanism of action of the endogenous inhibitor of PKC in the rat ovary. The addition of the phosphatase inhibitors calyculin-A (0.09 nM), microcystin-LR (6.4 nM), and okadaic acid (10 nM) resulted in the loss of PKC inhibitory activity and an increase in basal PKC activity in rat ovarian cytosol. In phosphatase assays, significant dephosphorylation of histone-III-S or myelin basic protein that had been phosphorylated by PKC occurred within 4 min after the addition of ovarian cytosol from the pseudopregnant rat. This dephosphorylation was prevented from the pseudopregnant rat. This dephosphorylation was prevented by the addition of calyculin-A (0.73 nM) and was removed by fractionation of ovarian cytosol on diethylaminoethyl cellulose. No inhibition of PKC activity was observed when the PKC-specific peptides AcMBP-(4-14) and [Ser25]PKC-(19-31) were used as the substrate for phosphorylation. In addition, rat ovarian cytosol did not exhibit phosphatase activity when the peptide AcMBP-(4-14) was used as the substrate. Addition of ovarian cytosol resulted in dephosphorylation of phosphorylase-alpha phosphorylated by phosphorylase kinase, but not dephosphorylation of histone-II-A or histone-VIII-S phosphorylated by PKA. The data suggest that the endogenous inhibitor of PKC in the rat ovary is a protein phosphatase. PMID:7689949

  5. The protein kinase C inhibitor enzastaurin exhibits antitumor activity against uveal melanoma.

    Directory of Open Access Journals (Sweden)

    Xinqi Wu

    Full Text Available GNAQ mutations at codon 209 have been recently identified in approximately 50% of uveal melanomas (UM and are reported to be oncogenic through activating the MAPK/Erk1/2 pathway. Protein kinase C (PKC is a component of signaling from GNAQ to Erk1/2. Inhibition of PKC might regulate GNAQ mutation-induced Erk1/2 activation, resulting in growth inhibition of UM cells carrying GNAQ mutations. UM cells carrying wild type or mutant GNAQ were treated with the PKC inhibitor enzastaurin. Effects on proliferation, apoptosis, and signaling events were evaluated. Enzastaurin downregulated the expression of several PKC isoforms including PKCβII PKCθ, PKCε and/or their phosphorylation in GNAQ mutated cells. Downregulation of these PKC isoforms in GNAQ mutated cells by shRNA resulted in reduced viability. Enzastaurin exhibited greater antiproliferative effect on GNAQ mutant cells than wild type cells through induction of G1 arrest and apoptosis. Enzastaurin-induced G1 arrest was associated with inhibition of Erk1/2 phosphorylation, downregulation of cyclin D1, and accumulation of cyclin dependent kinase inhibitor p27(Kip1. Furthermore, enzastaurin reduced the expression of antiapoptotic Bcl-2 and survivin in GNAQ mutant cells. Inhibition of Erk1/2 phosphorylation with a MEK specific inhibitor enhanced the sensitivity of GNAQ wild type cells to enzastaurin, accompanied by p27(Kip1 accumulation and/or inhibition of enzastaurin-induced survivin and Bcl-2 upregulation. PKC inhibitors such as enzastaurin have activity against UM cells carrying GNAQ mutations through inhibition of the PKC/Erk1/2 pathway and induction of G1 arrest and apoptosis. Inhibition of the PKC pathway provides a basis for clinical investigation in patients with UM.

  6. High-content screening identifies kinase inhibitors that overcome venetoclax resistance in activated CLL cells.

    Science.gov (United States)

    Oppermann, Sina; Ylanko, Jarkko; Shi, Yonghong; Hariharan, Santosh; Oakes, Christopher C; Brauer, Patrick M; Zúñiga-Pflücker, Juan C; Leber, Brian; Spaner, David E; Andrews, David W

    2016-08-18

    Novel agents such as the Bcl-2 inhibitor venetoclax (ABT-199) are changing treatment paradigms for chronic lymphocytic leukemia (CLL) but important problems remain. Although some patients exhibit deep and durable responses to venetoclax as a single agent, other patients harbor subpopulations of resistant leukemia cells that mediate disease recurrence. One hypothesis for the origin of resistance to venetoclax is by kinase-mediated survival signals encountered in proliferation centers that may be unique for individual patients. An in vitro microenvironment model was developed with primary CLL cells that could be incorporated into an automated high-content microscopy-based screen of kinase inhibitors (KIs) to identify agents that may improve venetoclax therapy in a personalized manner. Marked interpatient variability was noted for which KIs were effective; nevertheless, sunitinib was identified as the most common clinically available KI effective in overcoming venetoclax resistance. Examination of the underlying mechanisms indicated that venetoclax resistance may be induced by microenvironmental signals that upregulate antiapoptotic Bcl-xl, Mcl-1, and A1, which can be counteracted more efficiently by sunitinib than by ibrutinib or idelalisib. Although patient-specific drug responses are common, for many patients, combination therapy with sunitinib may significantly improve the therapeutic efficacy of venetoclax. PMID:27297795

  7. Discovery of Subtype Selective Janus Kinase (JAK) Inhibitors by Structure-Based Virtual Screening.

    Science.gov (United States)

    Bajusz, Dávid; Ferenczy, György G; Keserű, György M

    2016-01-25

    Janus kinase inhibitors represent a promising opportunity for the pharmaceutical intervention of various inflammatory and oncological indications. Subtype selective inhibition of these enzymes, however, is still a very challenging goal. In this study, a novel, customized virtual screening protocol was developed with the intention of providing an efficient tool for the discovery of subtype selective JAK2 inhibitors. The screening protocol involves protein ensemble-based docking calculations combined with an Interaction Fingerprint (IFP) based scoring scheme for estimating ligand affinities and selectivities, respectively. The methodology was validated in retrospective studies and was applied prospectively to screen a large database of commercially available compounds. Six compounds were identified and confirmed in vitro, with an indazole-based hit exhibiting promising selectivity for JAK2 vs JAK1. Having demonstrated that the described methodology is capable of identifying subtype selective chemical starting points with a favorable hit rate (11%), we believe that the presented screening concept can be useful for other kinase targets with challenging selectivity profiles. PMID:26682735

  8. Mitochondrial-Targeting MET Kinase Inhibitor Kills Erlotinib-Resistant Lung Cancer Cells.

    Science.gov (United States)

    Yang, Tianming; Ng, Wai Har; Chen, Huan; Chomchopbun, Kamon; Huynh, The Hung; Go, Mei Lin; Kon, Oi Lian

    2016-08-11

    Lung cancer cells harboring activating EGFR mutations acquire resistance to EGFR tyrosine kinase inhibitors (TKIs) by activating several bypass mechanisms, including MET amplification and overexpression. We show that a significant proportion of activated MET protein in EGFR TKI-resistant HCC827 lung cancer cells resides within the mitochondria. Targeting the total complement of MET in the plasma membrane and mitochondria should render these cells more susceptible to cell death and hence provide a means of circumventing drug resistance. Herein, the mitochondrial targeting triphenylphosphonium (TPP) moiety was introduced to the selective MET kinase inhibitor PHA665752. The resulting TPP analogue rapidly localized to the mitochondria of MET-overexpressing erlotinib-resistant HCC827 cells, partially suppressed the phosphorylation (Y1234/Y1235) of MET in the mitochondrial inner membrane and was as cytotoxic and apoptogenic as the parent compound. These findings provide support for the targeting of mitochondrial MET with a TPP-TKI conjugate as a means of restoring responsiveness to chemotherapy. PMID:27563407

  9. Tyrosine kinase inhibitors in pulmonary arterial hypertension: a double-edge sword?

    Science.gov (United States)

    Godinas, Laurent; Guignabert, Christophe; Seferian, Andrei; Perros, Frederic; Bergot, Emmanuel; Sibille, Yves; Humbert, Marc; Montani, David

    2013-10-01

    New treatments for pulmonary arterial hypertension (PAH) are a crucial need. The increased proliferation, migration, and survival of pulmonary vascular cells within the pulmonary artery wall in PAH have allowed successful transposition of pathophysiological elements from oncologic researches. Next steps will require translation of these biological advances in PAH therapeutic arsenal and guidelines. This review synthesizes recent data concerning the role of receptor tyrosine kinases and their inhibitors in PAH, with implications in animal models and humans. Results of clinical trials are now accumulating to establish beneficial role of tyrosine kinase inhibitors (TKIs) in PAH and further findings are expected in the near future. Beside this curative approach, evidences of a possible TKI-induced cardiotoxicity are emerging. These safety issues raise concern about a potential amplified harmful effect in PAH, a pathology characterized by an underlying cardiac dysfunction. In addition, analyses of PAH registries shed light on a selective pulmonary vascular toxicity triggered by TKIs, especially dasatinib. These possible dual effects of the TKIs in PAH need to be taken in account for future pharmacological development of this therapeutic class in PAH. PMID:24037637

  10. A Receptor Tyrosine Kinase Inhibitor, Dovitinib (TKI-258), Enhances BMP-2-Induced Osteoblast Differentiation In Vitro

    Science.gov (United States)

    Lee, Yura; Bae, Kyoung Jun; Chon, Hae Jung; Kim, Seong Hwan; Kim, Soon Ae; Kim, Jiyeon

    2016-01-01

    Dovitinib (TKI258) is a small molecule multi-kinase inhibitor currently in clinical phase I/II/III development for the treatment of various types of cancers. This drug has a safe and effective pharmacokinetic/pharmacodynamic profile. Although dovitinib can bind several kinases at nanomolar concentrations, there are no reports relating to osteoporosis or osteoblast differentiation. Herein, we investigated the effect of dovitinib on human recombinant bone morphogenetic protein (BMP)-2-induced osteoblast differentiation in a cell culture model. Dovitinib enhanced the BMP-2-induced alkaline phosphatase (ALP) induction, which is a representative marker of osteoblast differentiation. Dovitinib also stimulated the translocation of phosphorylated Smad1/5/8 into the nucleus and phosphorylation of mitogen-activated protein kinases, including ERK1/2 and p38. In addition, the mRNA expression of BMP-4, BMP-7, ALP, and OCN increased with dovitinib treatment. Our results suggest that dovitinib has a potent stimulating effect on BMP-2-induced osteoblast differentiation and this existing drug has potential for repositioning in the treatment of bone-related disorders. PMID:27025387

  11. 4-Oxo-1,4-dihydroquinoline-3-carboxamide Derivatives as New Axl Kinase Inhibitors.

    Science.gov (United States)

    Tan, Li; Zhang, Zhang; Gao, Donglin; Luo, Jinfeng; Tu, Zheng-Chao; Li, Zhengqiu; Peng, Lijie; Ren, Xiaomei; Ding, Ke

    2016-07-28

    Axl is a new potential target for anticancer drug discovery. A series of 4-oxo-1,4-dihydroquinoline-3-carboxamides were designed and synthesized as highly potent Axl kinase inhibitors. One of the most promising compounds, 9im, tightly bound with Axl protein and potently inhibited its kinase function with a Kd value of 2.7 nM and an IC50 value of 4.0 nM, respectively, while was obviously less potent against most of the 403 wild-type kinases evaluated at a relatively high concentration. The compound dose-dependently inhibited the TGF-β1-induced epithelial-mesenchymal transition (EMT) and suppressed the migration and invasion of MDA-MB-231 breast cancer cells. In addition, 9im also demonstrated reasonable pharmacokinetics properties in rats and exhibited in vivo therapeutic effect on hepatic metastasis in a xenograft model of highly metastatic 4T1 murine breast cancer cells. Compound 9im may serve as a lead compound for new anticancer drug discovery and a valuable research probe for further biological investigation on Axl. PMID:27379978

  12. The c-Met receptor tyrosine kinase inhibitor MP470 radiosensitizes glioblastoma cells

    International Nuclear Information System (INIS)

    Glioblastoma multiforme (GBM) is resistant to current cytotoxic therapies, in part because of enhanced DNA repair. Activation of the receptor tyrosine kinase c-Met has been shown to protect cancer cells from DNA damage. We hypothesized that inhibiting c-Met would decrease this protection and thus sensitize resistant tumor cells to the effects of radiation therapy. Eight human GBM cell lines were screened for radiosensitivity to the small-molecule c-Met inhibitor MP470 with colony-count assays. Double-strand (ds) DNA breaks was quantified by using antibodies to gamma H2AX. Western blotting demonstrate expression of RAD51, glycogen synthase kinase (GSK)-3β, and other proteins. A murine xenograft tumor flank model was used for in vivo radiosensitization studies. MP470 reduced c-Met phosphorylation and enhanced radiation-induced cell kill by 0.4 logs in SF767 cells. Cells pretreated with MP470 had more ds DNA damage than cells treated with radiation alone. Mechanistically, MP470 was shown to inhibit dsDNA break repair and increase apoptosis. MP470 influences various survival and DNA repair related proteins such as pAKT, RAD51 and GSK3β. In vivo, the addition of MP470 to radiation resulted in a tumor-growth-delay enhancement ratio of 2.9 over radiation alone and extended survival time. GBM is a disease site where radiation is often used to address both macroscopic and microscopic disease. Despite attempts at dose escalation outcomes remain poor. MP470, a potent small-molecule tyrosine kinase inhibitor of c-Met, radiosensitized several GBM cell lines both in vitro and in vivo, and may help to improve outcomes for patients with GBM

  13. Selectivity analysis of protein kinase CK2 inhibitors DMAT, TBB and resorufin in cisplatin-induced stress responses

    DEFF Research Database (Denmark)

    Fritz, Gerhard; Issinger, Olaf-Georg; Olsen, Birgitte Brinkmann

    2009-01-01

    Targeting protein kinases as a therapeutic approach to treat various diseases, especially cancer is currently a fast growing business. Although many inhibitors are available, exhibiting remarkable potency, the major challenge is their selectivity. Here we show that the protein kinase CK2 inhibitors...... DMAT, TBB and resorufin differ in their selectivity against PI3K family members, since PI3K and DNA-PK are subject to inhibition by DMAT and TBB, however, not by resorufin. TBB and DMAT treatment together with cisplatin lead to an inhibition of cisplatin-induced stress signaling (as detected...... by phosphorylation of JNK and H2AX). In the case of resorufin no interference with the stress-signaling pathway is observed, supporting the notion that TBB and DMAT interfere with upstream molecules involved in genotoxic stress signaling. We have also tested the protein kinase CK2 inhibitors with respect to cell...

  14. Therapeutic effects of tyroservatide on metastasis of lung cancer and its mechanism affecting integrin–focal adhesion kinase signal transduction

    Science.gov (United States)

    Huang, Yu-ting; Zhao, Lan; Fu, Zheng; Zhao, Meng; Song, Xiao-meng; Jia, Jing; Wang, Song; Li, Jin-ping; Zhu, Zhi-feng; Lin, Gang; Lu, Rong; Yao, Zhi

    2016-01-01

    Tyroservatide (YSV) can inhibit the growth and metastasis of mouse lung cancer significantly. This study investigated the therapeutic effects of tripeptide YSV on metastasis of human lung cancer cells and explored its possible mechanism that affects integrin–focal adhesion kinase (FAK) signal transduction in tumor cells. YSV significantly inhibited the adhesion and the invasion of highly metastatic human lung cancer cell lines 95D, A549, and NCI-H1299. In addition, YSV significantly inhibited phosphorylation of FAK Tyr397 and FAK Tyr576/577 in the 95D, A549, and NCI-H1299 human lung cancer cells in vitro. And the mRNA level and protein expression of FAK in these human lung cancer cells decreased at the same time. YSV also significantly inhibited mRNA and protein levels of integrin β1 and integrin β3 in the 95D, A549, and NCI-H1299 human lung cancer cells. Our research showed that YSV inhibited adhesion and invasion of human lung cancer cells and exhibited therapeutic effects on metastasis of lung cancer. PMID:27041993

  15. Computational Study of the Structure, the Flexibility, and the Electronic Circular Dichroism of Staurosporine - a Powerful Protein Kinase Inhibitor

    Science.gov (United States)

    Karabencheva-Christova, Tatyana G.; Singh, Warispreet; Christov, Christo Z.

    2014-07-01

    Staurosporine (STU) is a microbial alkaloid which is an universal kinase inhibitor. In order to understand its mechanism of action it is important to explore its structure-properties relationships. In this paper we provide the results of a computational study of the structure, the chiroptical properties, the conformational flexibility of STU as well as the correlation between the electronic circular dichroism (ECD) spectra and the structure of its complex with anaplastic lymphoma kinase.

  16. Identification of hematein as a novel inhibitor of protein kinase CK2 from a natural product library

    International Nuclear Information System (INIS)

    Casein kinase 2 (CK2) is dysregulated in various human cancers and is a promising target for cancer therapy. To date, there is no small molecular CK2 inhibitor in clinical trial yet. With the aim to identify novel CK2 inhibitors, we screened a natural product library. We adopted cell-based proliferation and CK2 kinase assays to screen CK2 inhibitors from a natural compound library. Dose-dependent response of CK2 inhibitors in vitro was determined by a radioisotope kinase assay. Western blot analysis was used to evaluate down stream Akt phosphorylation and apoptosis. Apoptosis was also evaluated by annexin-V/propidium iodide (PI) labeling method using flow cytometry. Inhibition effects of CK2 inhibitors on the growth of cancer and normal cells were evaluated by cell proliferation and viability assays. Hematein was identified as a novel CK2 inhibitor that is highly selective among a panel of kinases. It appears to be an ATP non-competitive and partially reversible CK2 inhibitor with an IC50 value of 0.55 μM. In addition, hematein inhibited cancer cell growth partially through down-regulation of Akt phosphorylation and induced apoptosis in these cells. Furthermore, hematein exerted stronger inhibition effects on the growth of cancer cells than in normal cells. In this study, we showed that hematein is a novel selective and cell permeable small molecule CK2 inhibitor. Hematein showed stronger growth inhibition effects to cancer cells when compared to normal cells. This compound may represent a promising class of CK2 inhibitors

  17. Treatment of Experimental Candida Sepsis with a Janus Kinase Inhibitor Controls Inflammation and Prolongs Survival.

    Science.gov (United States)

    Tsirigotis, P; Papanikolaou, N; Elefanti, A; Konstantinou, P; Gkirkas, K; Rontogianni, D; Siafakas, N; Karakitsos, P; Roilides, E; Dimitriadis, G; Zerva, L; Meletiadis, J

    2015-12-01

    Janus kinases (JAK) are intracellular tyrosine kinases that transduce cytokine-mediated signals to the nucleus, promoting gene expression. Cytokines play a major role in microbial sepsis, which is often associated with uncontrolled inflammation leading to death. JAK inhibitors have been used for the treatment of several autoimmune diseases by modulating immune response, but they have never been tested against microbial sepsis. Ruxolitinib is a small-molecule inhibitor of JAK1/2 proteins, which are involved in the downstream signaling pathway of the vast majority of proinflammatory and anti-inflammatory cytokines. We therefore studied the effect of ruxolitinib in a mouse model of sepsis due to Candida albicans. When ruxolitinib therapy (50 mg/kg [of body weight]/day) was started 1 day before infection, the median survival time was reduced by 3 days, the fungal loads in all organs were higher, the inflammation was significantly less, and serum tumor necrosis factor alpha (TNF-α) and interleukin 10 (IL-10) levels and IL-10/TNF-α ratios were higher than in controls. When ruxolitinib therapy (50 to 1.5 mg/kg/day) was started 1 day after infection, an inverted-U relationship was found, with 6.25 mg/kg/day prolonging median survival time by 6 days, resulting in similar fungal loads, less inflammation, and similar cytokine levels but higher IL-10/TNF-α ratios than the controls. The optimal dose of ruxolitinib controlled infection and prolonged survival with less inflammation than in control animals. Administration of JAK inhibitors may be a promising therapeutic adjunct that needs further investigation.

  18. Mutations in G protein β subunits promote transformation and kinase inhibitor resistance.

    Science.gov (United States)

    Yoda, Akinori; Adelmant, Guillaume; Tamburini, Jerome; Chapuy, Bjoern; Shindoh, Nobuaki; Yoda, Yuka; Weigert, Oliver; Kopp, Nadja; Wu, Shuo-Chieh; Kim, Sunhee S; Liu, Huiyun; Tivey, Trevor; Christie, Amanda L; Elpek, Kutlu G; Card, Joseph; Gritsman, Kira; Gotlib, Jason; Deininger, Michael W; Makishima, Hideki; Turley, Shannon J; Javidi-Sharifi, Nathalie; Maciejewski, Jaroslaw P; Jaiswal, Siddhartha; Ebert, Benjamin L; Rodig, Scott J; Tyner, Jeffrey W; Marto, Jarrod A; Weinstock, David M; Lane, Andrew A

    2015-01-01

    Activating mutations in genes encoding G protein α (Gα) subunits occur in 4-5% of all human cancers, but oncogenic alterations in Gβ subunits have not been defined. Here we demonstrate that recurrent mutations in the Gβ proteins GNB1 and GNB2 confer cytokine-independent growth and activate canonical G protein signaling. Multiple mutations in GNB1 affect the protein interface that binds Gα subunits as well as downstream effectors and disrupt Gα interactions with the Gβγ dimer. Different mutations in Gβ proteins clustered partly on the basis of lineage; for example, all 11 GNB1 K57 mutations were in myeloid neoplasms, and seven of eight GNB1 I80 mutations were in B cell neoplasms. Expression of patient-derived GNB1 variants in Cdkn2a-deficient mouse bone marrow followed by transplantation resulted in either myeloid or B cell malignancies. In vivo treatment with the dual PI3K-mTOR inhibitor BEZ235 suppressed GNB1-induced signaling and markedly increased survival. In several human tumors, mutations in the gene encoding GNB1 co-occurred with oncogenic kinase alterations, including the BCR-ABL fusion protein, the V617F substitution in JAK2 and the V600K substitution in BRAF. Coexpression of patient-derived GNB1 variants with these mutant kinases resulted in inhibitor resistance in each context. Thus, GNB1 and GNB2 alterations confer transformed and resistance phenotypes across a range of human tumors and may be targetable with inhibitors of G protein signaling. PMID:25485910

  19. PKCθ signaling is required for myoblast fusion by regulating the expression of caveolin-3 and β1D integrin upstream focal adhesion kinase

    OpenAIRE

    Madaro, Luca; Marrocco, Valeria; Fiore, Piera; Aulino, Paola; Smeriglio, Piera; Adamo, Sergio; Molinaro, Mario; Bouché, Marina

    2011-01-01

    Fusion of mononucleated myoblasts to form multinucleated myofibers is an essential phase of skeletal myogenesis, which occurs during muscle development as well as during postnatal life for muscle growth, turnover, and regeneration. Many cell adhesion proteins, including integrins, have been shown to be important for myoblast fusion in vertebrates, and recently focal adhesion kinase (FAK), has been proposed as a key mediator of myoblast fusion. Here we focused on the possible role of PKCθ, the...

  20. Identification of a new membrane-permeable inhibitor against inositol-1,4,5-trisphosphate-3-kinase A.

    Science.gov (United States)

    Schröder, Dominik; Rehbach, Christoph; Seyffarth, Carola; Neuenschwander, Martin; Kries, Jens V; Windhorst, Sabine

    2013-09-20

    Ectopic expression of the neuron-specific inositol-1,4,5-trisphosphate-3-kinase A (ITPKA) in lung cancer cells increases their metastatic potential because the protein exhibits two actin regulating activities; it bundles actin filaments and regulates inositol-1,4,5-trisphosphate (InsP3)-mediated calcium signals by phosphorylating InsP3. Thus, in order to inhibit the metastasis-promoting activity of ITPKA, both its actin bundling and its InsP3kinase activity has to be blocked. In this study, we performed a high throughput screen in order to identify specific and membrane-permeable substances against the InsP3kinase activity. Among 341,44 small molecules, 237 compounds (0.7%) were identified as potential InsP3kinase inhibitors. After determination of IC50-values, the three compounds with highest specificity and highest hydrophobicity (EPPC-3, BAMB-4, MEPTT-3) were further characterized. Only BAMB-4 was nearly completely taken up by H1299 cells and remained stable after cellular uptake, thus exhibiting a robust stability and a high membrane permeability. Determination of the inhibitor type revealed that BAMB-4 belongs to the group of mixed type inhibitors. Taken together, for the first time we identified a highly membrane-permeable inhibitor against the InsP3kinase activity of ITPKA providing the possibility to partly inhibit the metastasis-promoting effect of ITPKA in lung tumor cells. PMID:23981806

  1. A high-content EMT screen identifies multiple receptor tyrosine kinase inhibitors with activity on TGFβ receptor

    Science.gov (United States)

    Ackerknecht, Sabine; Lehembre, François; Fink, Tobias; Stritt, Manuel; Wirth, Matthias; Pavan, Simona; Bill, Ruben; Regenass, Urs; Christofori, Gerhard; Meyer-Schaller, Nathalie

    2016-01-01

    An epithelial to mesenchymal transition (EMT) enables epithelial tumor cells to break out of the primary tumor mass and to metastasize. Understanding the molecular mechanisms driving EMT in more detail will provide important tools to interfere with the metastatic process. To identify pharmacological modulators and druggable targets of EMT, we have established a novel multi-parameter, high-content, microscopy-based assay and screened chemical compounds with activities against known targets. Out of 3423 compounds, we have identified 19 drugs that block transforming growth factor beta (TGFβ)-induced EMT in normal murine mammary gland epithelial cells (NMuMG). The active compounds include inhibitors against TGFβ receptors (TGFBR), Rho-associated protein kinases (ROCK), myosin II, SRC kinase and uridine analogues. Among the EMT-repressing compounds, we identified a group of inhibitors targeting multiple receptor tyrosine kinases, and biochemical profiling of these multi-kinase inhibitors reveals TGFBR as a thus far unknown target of their inhibitory spectrum. These findings demonstrate the feasibility of a multi-parameter, high-content microscopy screen to identify modulators and druggable targets of EMT. Moreover, the newly discovered “off-target” effects of several receptor tyrosine kinase inhibitors have important consequences for in vitro and in vivo studies and might beneficially contribute to the therapeutic effects observed in vivo. PMID:27036020

  2. Potent quinoxaline-based inhibitors of PDGF receptor tyrosine kinase activity. Part 2: the synthesis and biological activities of RPR127963 an orally bioavailable inhibitor.

    Science.gov (United States)

    He, Wei; Myers, Michael R; Hanney, Barbara; Spada, Alfred P; Bilder, Glenda; Galzcinski, Helen; Amin, Dilip; Needle, Saul; Page, Ken; Jayyosi, Zaid; Perrone, Mark H

    2003-09-15

    RPR127963 demonstrates an excellent pharmacokinetic profile in several species and was found to be efficacious in the prevention of restenosis in a Yucatan mini-pig model upon oral administration of 1-5 mg/kg. The in vitro selectivity profile and SAR of the highly optimized PDGF-R tyrosine kinase inhibitor are highlighted.

  3. Non-hinge-binding pyrazolo[1,5-a]pyrimidines as potent B-Raf kinase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Berger, Dan M.; Torres, Nancy; Dutia, Minu; Powell, Dennis; Ciszewski, Greg; Gopalsamy, Ariamala; Levin, Jeremy I.; Kim, Kyung-Hee; Xu, Weixin; Wilhelm, James; Hu, YongBo; Collins, Karen; Feldberg, Larry; Kim, Steven; Frommer, Eileen; Wojciechowicz, Donald; Mallon, Robert; (Wyeth)

    2010-11-19

    As part of our research effort to discover B-Raf kinase inhibitors, we prepared a series of C-3 substituted N-(3-(pyrazolo[1,5-a]pyrimidin-7-yl)phenyl)-3-(trifluoromethyl)benzamides. X-ray crystallography studies revealed that one of the more potent inhibitors (10n) bound to B-Raf kinase without forming a hinge-binding hydrogen bond. With basic amine residues appended to C-3 aryl residues, cellular activity and solubility were enhanced over previously described compounds of this class.

  4. Doxycycline reduces the migration of tuberous sclerosis complex-2 null cells - effects on RhoA-GTPase and focal adhesion kinase.

    Science.gov (United States)

    Ng, Ho Yin; Oliver, Brian Gregory George; Burgess, Janette Kay; Krymskaya, Vera P; Black, Judith Lee; Moir, Lyn M

    2015-11-01

    Lymphangioleiomyomatosis (LAM) is associated with dysfunction of the tuberous sclerosis complex (TSC) leading to enhanced cell proliferation and migration. This study aims to examine whether doxycycline, a tetracycline antibiotic, can inhibit the enhanced migration of TSC2-deficient cells, identify signalling pathways through which doxycycline works and to assess the effectiveness of combining doxycycline with rapamycin (mammalian target of rapamycin complex 1 inhibitor) in controlling cell migration, proliferation and wound closure. TSC2-positive and TSC2-negative mouse embryonic fibroblasts (MEF), 323-TSC2-positive and 323-TSC2-null MEF and Eker rat uterine leiomyoma (ELT3) cells were treated with doxycycline or rapamycin alone, or in combination. Migration, wound closure and proliferation were assessed using a transwell migration assay, time-lapse microscopy and manual cell counts respectively. RhoA-GTPase activity, phosphorylation of p70S6 kinase (p70S6K) and focal adhesion kinase (FAK) in TSC2-negative MEF treated with doxycycline were examined using ELISA and immunoblotting techniques. The enhanced migration of TSC2-null cells was reduced by doxycycline at concentrations as low as 20 pM, while the rate of wound closure was reduced at 2-59 μM. Doxycycline decreased RhoA-GTPase activity and phosphorylation of FAK in these cells but had no effect on the phosphorylation of p70S6K, ERK1/2 or AKT. Combining doxycycline with rapamycin significantly reduced the rate of wound closure at lower concentrations than achieved with either drug alone. This study shows that doxycycline inhibits TSC2-null cell migration. Thus doxycycline has potential as an anti-migratory agent in the treatment of diseases with TSC2 dysfunction. PMID:26282580

  5. A new trend in pathogenetic treatment of rheumatoid arthritis: tofacitinib, the first inhibitor of Janus kinase

    Directory of Open Access Journals (Sweden)

    Dmitry Evgenyevich Karateev

    2014-01-01

    Full Text Available The Problem of effective treatment of rheumatoid arthritis (RA has not been solved yet. In patients with an inadequate response to the synthetic disease-modifying antirheumatic drugs (DMARDs, TNF inhibitors and other genetically engineered (GE drugs may give an incomplete effect or be totally ineffective in 20–40% of cases. The search for new therapeutic options is very active in many directions, including modulation of intracellular signaling pathways. The most impressive clinical results in RA patients have been achieved for Janus kinase (JAK inhibitor, tofacitinib, – Tofa (CP-690,550, a low molecular weight drug for oral administration. Unlike the conventional synthetic DMARD, Tofa belongs to targeted therapy drugs; its pharmacological effects largely resemble those of GE drugs (blockade of the biological effects of cytokines. In particular, some features of its mechanism of action (e.g., interleukin 6 inhibition make it similar to tocilizumab. In all trials, Tofa proved to exhibit high clinical efficacy and satisfactory safety. Tofa was shown to be significantly more effective than methotrexate and placebo (in monotherapy, as well as in combination with DMARDs in RA patients with an inadequate response to standard DMARDs and TNFa inhibitors (regarding response to treatment, individual parameters of disease activity, achievement of low disease activity and remission, functional impairment. Furthermore, Tofa can inhibit joint damage progression.

  6. Structure-guided development of specific pyruvate dehydrogenase kinase inhibitors targeting the ATP-binding pocket.

    Science.gov (United States)

    Tso, Shih-Chia; Qi, Xiangbing; Gui, Wen-Jun; Wu, Cheng-Yang; Chuang, Jacinta L; Wernstedt-Asterholm, Ingrid; Morlock, Lorraine K; Owens, Kyle R; Scherer, Philipp E; Williams, Noelle S; Tambar, Uttam K; Wynn, R Max; Chuang, David T

    2014-02-14

    Pyruvate dehydrogenase kinase isoforms (PDKs 1-4) negatively regulate activity of the mitochondrial pyruvate dehydrogenase complex by reversible phosphorylation. PDK isoforms are up-regulated in obesity, diabetes, heart failure, and cancer and are potential therapeutic targets for these important human diseases. Here, we employed a structure-guided design to convert a known Hsp90 inhibitor to a series of highly specific PDK inhibitors, based on structural conservation in the ATP-binding pocket. The key step involved the substitution of a carbonyl group in the parent compound with a sulfonyl in the PDK inhibitors. The final compound of this series, 2-[(2,4-dihydroxyphenyl)sulfonyl]isoindoline-4,6-diol, designated PS10, inhibits all four PDK isoforms with IC50 = 0.8 μM for PDK2. The administration of PS10 (70 mg/kg) to diet-induced obese mice significantly augments pyruvate dehydrogenase complex activity with reduced phosphorylation in different tissues. Prolonged PS10 treatments result in improved glucose tolerance and notably lessened hepatic steatosis in the mouse model. The results support the pharmacological approach of targeting PDK to control both glucose and fat levels in obesity and type 2 diabetes. PMID:24356970

  7. Neurite outgrowth resistance to rho kinase inhibitors in PC12 Adh cell.

    Science.gov (United States)

    Yin, Hua; Hou, Xiaolin; Tao, Tingrui; Lv, Xiaoman; Zhang, Luyong; Duan, Weigang

    2015-05-01

    Rho kinase (ROCK) inhibitor is a promising agent for neural injury disorders, which mechanism is associated with neurite outgrowth. However, neurite outgrowth resistance occurred when PC12 Adh cell was treated with ROCK inhibitors for a longer time. PC12 Adh cells were treated with ROCK inhibitor Y27632 or NGF for different durations. Neurite outgrowth resistance occurred when PC12 Adh cell exposed to Y27632 (33 µM) for 3 or more days, but not happen when exposed to nerve growth factor (NGF, 100 ng/mL). The gene expression in the PC12 Adh cells treated with Y27632 (33 µM) or NGF (100 ng/mL) for 2 or 4 days was assayed by gene microarray, and the reliability of the results were confirmed by real-time RT-PCR. Cluster analysis proved that the gene expression profile of PC12 Adh cell treated with Y27632 for 4 days was different from that treated with Y27632 for 2 days and those treated with NGF for 2 and 4 days, respectively. Pathway analysis hinted that the neurite outgrowth resistance could be associated with up-regulation of inflammatory pathways, especially rno04610 (complement and coagulation cascades), and down-regulation of cell cycle pathways, especially rno04110.

  8. Third generation tyrosine kinase inhibitors and their development in advanced renal cell carcinoma.

    Science.gov (United States)

    Bukowski, Ronald M

    2012-01-01

    Angiogenesis in general and the vascular endothelial growth factor (VEGF) signaling axis in particular is a validated target in renal cell carcinoma (RCC). Clear-cell carcinoma of the kidney is now recognized as a malignancy that is sensitive to inhibitors of the VEGF pathway. Treatment options for patients with metastatic renal cell carcinoma have evolved in dramatic fashion over the past 6 years, and a new paradigm has developed. The cytokines interferon-α and interleukin-2 were previously utilized for therapy, but since December 2005, six new agents have been approved in the United States for the treatment of advanced RCC. Two are tyrosine kinase inhibitors (TKI's) including sunitinib and recently pazopanib, and the multikinase inhibitor sorafenib. The current review examines the evolving data with the next generation of TKI's, axitinib and tivozanib being developed for the treatment of advanced RCC. These agents were synthesized to provide increased target specificity and enhanced target inhibition. The preclinical and clinical data are examined, an overview of the development of these TKI's is provided, and discussion plus speculation concerning their potential roles as RCC therapy is provided.

  9. Structure-Based Design of Potent and Selective 3-Phosphoinositide-Dependent Kinase-1 (PDK1) Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Medina, Jesus R.; Becker, Christopher J.; Blackledge, Charles W.; Duquenne, Celine; Feng, Yanhong; Grant, Seth W.; Heerding, Dirk; Li, William H.; Miller, William H.; Romeril, Stuart P.; Scherzer, Daryl; Shu, Arthur; Bobko, Mark A.; Chadderton, Antony R.; Dumble, Melissa; Gardiner, Christine M.; Gilbert, Seth; Liu, Qi; Rabindran, Sridhar K.; Sudakin, Valery; Xiang, Hong; Brady, Pat G.; Campobasso, Nino; Ward, Paris; Axten, Jeffrey M. (GSKPA)

    2014-10-02

    Phosphoinositide-dependent protein kinase-1(PDK1) is a master regulator of the AGC family of kinases and an integral component of the PI3K/AKT/mTOR pathway. As this pathway is among the most commonly deregulated across all cancers, a selective inhibitor of PDK1 might have utility as an anticancer agent. Herein we describe our lead optimization of compound 1 toward highly potent and selective PDK1 inhibitors via a structure-based design strategy. The most potent and selective inhibitors demonstrated submicromolar activity as measured by inhibition of phosphorylation of PDK1 substrates as well as antiproliferative activity against a subset of AML cell lines. In addition, reduction of phosphorylation of PDK1 substrates was demonstrated in vivo in mice bearing OCl-AML2 xenografts. These observations demonstrate the utility of these molecules as tools to further delineate the biology of PDK1 and the potential pharmacological uses of a PDK1 inhibitor.

  10. Modulation of endogenous Cysteine Protease Inhibitor (ICP) 1 expression in Entamoeba histolytica affects amoebic adhesion to Extracellular Matrix proteins.

    Science.gov (United States)

    Lee, Young Ah; Saito-Nakano, Yumiko; Kim, Kyeong Ah; Min, Arim; Nozaki, Tomoyoshi; Shin, Myeong Heon

    2015-02-01

    Entamoeba histolytica is an enteric tissue-invading protozoan parasite that causes amoebic colitis and occasionally liver abscess in humans. During tissue invasion, amoebic adhesion to host components is an important event for host cell death leading to successful invasion and infection. Among amoebic virulence factors, Gal/GalNAc lectin is known to be major adhesion factor to host cells. In this study, we investigated the role of amoebic secreted CP (Cysteine Proteases) in amoebic adhesion to extracellular matrix (ECM) protein using CP inhibitor and E. histolytica strains in which the endogenous inhibitor of cysteine protease (ICP) 1 gene was overexpressed (ICP1(+)) or repressed by antisense small RNA-mediated gene silencing (ICP1(-)). We found that pretreatment of wild-type amoebae with CP inhibitor E64, or thiol-group modifiers such as diamide and N-Ethylmaleimide resulted in a significant decrease in adhesion to laminin and collagen ECM proteins. Furthermore, ICP1(+) strain, with a reduction of secreted CP activity, exhibited reduced ability by 40% to adhere to laminin. In contrast, ICP1(-) strain, with a 1.9-fold increase of secreted CP activity, showed a two-fold increase in amoebic adherence to laminin compared to the control strain. In addition, total amount of secreted CP5 was decreased in ICP1(+) amoeba. Conversely, total amount of secreted CP1 and mature-form CP5 were increased in ICP1(-) amoeba. We also found that ICP1 was secreted into extracellular milieu. These results suggest that secreted CP activity by E. histolytica may be an important factor affecting adhesion to host proteins, and regulation of CP secretion by ICP plays a major role in pathogenesis. This study provides insight into the CP-mediated tissue pathogenesis in amoeba-invaded lesions during human amoebiasis.

  11. Receptor tyrosine kinase (c-Kit) inhibitors: a potential therapeutic target in cancer cells

    Science.gov (United States)

    Abbaspour Babaei, Maryam; Kamalidehghan, Behnam; Saleem, Mohammad; Huri, Hasniza Zaman; Ahmadipour, Fatemeh

    2016-01-01

    c-Kit, a receptor tyrosine kinase, is involved in intracellular signaling, and the mutated form of c-Kit plays a crucial role in occurrence of some cancers. The function of c-Kit has led to the concept that inhibiting c-Kit kinase activity can be a target for cancer therapy. The promising results of inhibition of c-Kit for treatment of cancers have been observed in some cancers such as gastrointestinal stromal tumor, acute myeloid leukemia, melanoma, and other tumors, and these results have encouraged attempts toward improvement of using c-Kit as a capable target for cancer therapy. This paper presents the findings of previous studies regarding c-Kit as a receptor tyrosine kinase and an oncogene, as well as its gene targets and signaling pathways in normal and cancer cells. The c-Kit gene location, protein structure, and the role of c-Kit in normal cell have been discussed. Comprehending the molecular mechanism underlying c-Kit-mediated tumorogenesis is consequently essential and may lead to the identification of future novel drug targets. The potential mechanisms by which c-Kit induces cellular transformation have been described. This study aims to elucidate the function of c-Kit for future cancer therapy. In addition, it has c-Kit inhibitor drug properties and their functions have been listed in tables and demonstrated in schematic pictures. This review also has collected previous studies that targeted c-Kit as a novel strategy for cancer therapy. This paper further emphasizes the advantages of this approach, as well as the limitations that must be addressed in the future. Finally, although c-Kit is an attractive target for cancer therapy, based on the outcomes of treatment of patients with c-Kit inhibitors, it is unlikely that Kit inhibitors alone can lead to cure. It seems that c-Kit mutations alone are not sufficient for tumorogenesis, but do play a crucial role in cancer occurrence. PMID:27536065

  12. Kinase inhibitor profile for human nek1, nek6, and nek7 and analysis of the structural basis for inhibitor specificity.

    Science.gov (United States)

    Moraes, Eduardo Cruz; Meirelles, Gabriela Vaz; Honorato, Rodrigo Vargas; de Souza, Tatiana de Arruda Campos Brasil; de Souza, Edmarcia Elisa; Murakami, Mario Tyago; de Oliveira, Paulo Sergio Lopes; Kobarg, Jörg

    2015-01-01

    Human Neks are a conserved protein kinase family related to cell cycle progression and cell division and are considered potential drug targets for the treatment of cancer and other pathologies. We screened the activation loop mutant kinases hNek1 and hNek2, wild-type hNek7, and five hNek6 variants in different activation/phosphorylation statesand compared them against 85 compounds using thermal shift denaturation. We identified three compounds with significant Tm shifts: JNK Inhibitor II for hNek1(Δ262-1258)-(T162A), Isogranulatimide for hNek6(S206A), andGSK-3 Inhibitor XIII for hNek7wt. Each one of these compounds was also validated by reducing the kinases activity by at least 25%. The binding sites for these compounds were identified by in silico docking at the ATP-binding site of the respective hNeks. Potential inhibitors were first screened by thermal shift assays, had their efficiency tested by a kinase assay, and were finally analyzed by molecular docking. Our findings corroborate the idea of ATP-competitive inhibition for hNek1 and hNek6 and suggest a novel non-competitive inhibition for hNek7 in regard to GSK-3 Inhibitor XIII. Our results demonstrate that our approach is useful for finding promising general and specific hNekscandidate inhibitors, which may also function as scaffolds to design more potent and selective inhibitors. PMID:25591119

  13. Antiproliferative and pro-apoptotic effects afforded by novel Src-kinase inhibitors in human neuroblastoma cells

    International Nuclear Information System (INIS)

    Neuroblastoma (NB) is the second most common solid malignancy of childhood that usually undergoes rapid progression with a poor prognosis upon metastasis. The Src-family tyrosine kinases (SFKs) are a group of proteins involved in cancer development and invasiveness that seem to play an important role in the NB carcinogenesis. To determine cell proliferation, the growth rate was evaluated by both MTT test and cells counted. Analysis of DNA content was performed for the evaluation of the cell cycle and apoptosis. To characterize the mechanisms underlying the antiproliferative effects induced by SI 34, a novel pyrazolo-pyrimidine derivative provided with Src inhibitory activity, the involvement of some cellular pathways that are important for cell proliferation and survival was investigated by western blot assays. In particular, the contribution of cyclins, Src and ERK were examined. Finally, experiments of cell adhesion and invasiveness were performed. Treatment of SH-SY5Y human NB cells and CHP100 human neuroepithelioma (NE) cultures with three novel pyrazolo[3,4-d]pyrimidine derivatives, namely SI 34, SI 35 and SI 83, inhibits the cell proliferation in a time and concentration-dependent manner. The maximal effect was obtained after 72 hours incubation with SI 34 10 μM. Fluorescence microscopy experiments, flow cytometry analysis and determination of caspase-3 activity by fluorimetric assays showed that SI 34 induced SH-SY5Y apoptosis. Moreover, SI 34 determined cell cycle arrest at the G0/G1 phase, paralleled by a decreased expression of cyclin D1. Furthermore, our data indicate that SI 34 reduces the SH-SY5Y cells adhesion and invasiveness. Evidence that SI 34 inhibits the Src and the ERK-phosphorylation, suggests the mechanism through which it exerts its effects in SH-SY5Y cells. Our study shows the ability of this pyrazolo-pyrimidine Src inhibitor in reducing the growth and the invasiveness of human NB cells, suggesting a promising role as novel drug in the

  14. Structure-based design, discovery and development of checkpoint kinase inhibitors as potential anti-cancer therapies

    Science.gov (United States)

    Matthews, Thomas P; Jones, Alan M; Collins, Ian

    2014-01-01

    Introduction Checkpoint kinase inhibitors offer the promise of enhancing the effectiveness of widely prescribed cancer chemotherapies and radiotherapy by inhibiting the DNA damage response, as well as the potential for single agent efficacy. Areas covered This article surveys structural insights into the checkpoint kinases CHK1 and CHK2 that have been exploited to enhance the selectivity and potency of small molecule inhibitors. The use of mechanistic cellular assays to guide the optimisation of inhibitors is reviewed. The status of the current clinical candidates and emerging new clinical contexts for CHK1 and CHK2 inhibitors are discussed, including the prospects for single agent efficacy. Expert opinion Protein bound water molecules play key roles in structural features that can be targeted to gain high selectivity for either enzyme. The results of early phase clinical trials of checkpoint inhibitors have been mixed, but significant progress has been made in testing the combination of CHK1 inhibitors with genotoxic chemotherapy. Second generation CHK1 inhibitors are likely to benefit from increased selectivity and oral bioavailability. While the optimum therapeutic context for CHK2 inhibition remains unclear, the emergence of single agent preclinical efficacy for CHK1 inhibitors in specific tumour types exhibiting constitutive replication stress represents exciting progress in exploring the therapeutic potential of these agents. PMID:23594139

  15. Targeting Mitogen-Activated Protein Kinase-Activated Protein Kinase 2 (MAPKAPK2, MK2): Medicinal Chemistry Efforts To Lead Small Molecule Inhibitors to Clinical Trials.

    Science.gov (United States)

    Fiore, Mario; Forli, Stefano; Manetti, Fabrizio

    2016-04-28

    The p38/MAPK-activated kinase 2 (MK2) pathway is involved in a series of pathological conditions (inflammation diseases and metastasis) and in the resistance mechanism to antitumor agents. None of the p38 inhibitors entered advanced clinical trials because of their unwanted systemic side effects. For this reason, MK2 was identified as an alternative target to block the pathway but avoiding the side effects of p38 inhibition. However, ATP-competitive MK2 inhibitors suffered from low solubility, poor cell permeability, and scarce kinase selectivity. Fortunately, non-ATP-competitive inhibitors of MK2 have been already discovered that allowed circumventing the selectivity issue. These compounds showed the additional advantage to be effective at lower concentrations in comparison to the ATP-competitive inhibitors. Therefore, although the significant difficulties encountered during the development of these inhibitors, MK2 is still considered as an attractive target to treat inflammation and related diseases to prevent tumor metastasis and to increase tumor sensitivity to chemotherapeutics.

  16. Ibrutinib: a novel Bruton's tyrosine kinase inhibitor with outstanding responses in patients with chronic lymphocytic leukemia.

    Science.gov (United States)

    Barrientos, Jacqueline; Rai, Kanti

    2013-08-01

    New treatment options are urgently needed for patients with relapsed chronic lymphocytic leukemia (CLL) who fail to respond to currently available therapies or cannot achieve a sustained response. Moreover, targeted agents with less myelotoxicity are necessary to treat patients with multiple comorbidities who would otherwise be unable to tolerate standard regimens. Ibrutinib, a Bruton's tyrosine kinase inhibitor, has shown highly encouraging results in phase I/II trials in patients with treatment-naive, relapsed and refractory CLL even in the presence of high risk disease or poor prognostic markers. In phase I/II trials, ibrutinib 420 mg or 840 mg - given continuously as single agent or at a dose of 420 mg daily in combination with a monoclonal antibody or chemoimmunotherapy - has been associated with high response rates and durable clinical remissions. Phase II and III trials are currently under way for treatment-naive patients, relapsed/refractory patients, and for those patients harboring a 17p deletion.

  17. Design, Synthesis and Biological Evaluation of Benzohydrazide Derivatives Containing Dihydropyrazoles as Potential EGFR Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Hai-Chao Wang

    2016-08-01

    Full Text Available A series of novel benzohydrazide derivatives containing dihydropyrazoles have been synthesized as potential epidermal growth factor receptor (EGFR kinase inhibitors and their biological activities as potential antiproliferative agents have been evaluated. Among these compounds, compound H20 exhibited the most potent antiproliferative activity against four cancer cell line variants (A549, MCF-7, HeLa, HepG2 with IC50 values of 0.46, 0.29, 0.15 and 0.21 μM respectively, which showed the most potent EGFR inhibition activities (IC50 = 0.08 μM for EGFR. Molecular modeling simulation studies were performed in order to predict the biological activity and activity relationship (SAR of these benzohydrazide derivatives. These results suggested that compound H20 may be a promising anticancer agent.

  18. A novel approach in treatment of rheumatoid arthritis: Janus kinase inhibitors

    Directory of Open Access Journals (Sweden)

    Sangeeta Bhanwra

    2015-06-01

    Full Text Available Janus kinase (JAK inhibitors are a new class of drugs that inhibit JAK enzymes, which are the main signal transducers for the majority of cytokines, growth factors, and interferons. These drugs work from inside the cell and are unique in a way that their action interrupts the signaling involved in the inflammation. They include drugs like ruxolitinib, tofacitinib, both of which have been US Food and Drug Administration (USFDA approved, and many others which are currently under trials. Tofacitinib was approved by USFDA in November 2012 for oral use in patients suffering with moderate to severe rheumatoid arthritis and do not respond to methotrexate. [Int J Basic Clin Pharmacol 2015; 4(3.000: 598-600

  19. Design and synthesis of orally bioavailable serum and glucocorticoid-regulated kinase 1 (SGK1) inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, Marlys; Washburn, David G.; Hoang, Tram H.; Manns, Sharada; Frazee, James S.; Nakamura, Hiroko; Patterson, Jaclyn R.; Trizna, Walter; Wu, Charlene; Azzarano, Leonard M.; Nagilla, Rakesh; Nord, Melanie; Trejo, Rebecca; Head, Martha S.; Zhao, Baoguang; Smallwood, Angela M.; Hightower, Kendra; Laping, Nicholas J.; Schnackenberg, Christine G.; Thompson, Scott K.; (GSKPA)

    2010-09-27

    The lead serum and glucocorticoid-related kinase 1 (SGK1) inhibitors 4-(5-phenyl-1H-pyrrolo[2,3-b]pyridin-3-yl)benzoic acid (1) and {l_brace}4-[5-(2-naphthalenyl)-1H-pyrrolo[2,3-b]pyridin-3-yl]phenyl{r_brace}acetic acid (2) suffer from low DNAUC values in rat, due in part to formation and excretion of glucuronic acid conjugates. These PK/glucuronidation issues were addressed either by incorporating a substituent on the 3-phenyl ring ortho to the key carboxylate functionality of 1 or by substituting on the group in between the carboxylate and phenyl ring of 2. Three of these analogs have been identified as having good SGK1 inhibition potency and have DNAUC values suitable for in vivo testing.

  20. Design and synthesis of orally bioavailable serum and glucocorticoid-regulated kinase 1 (SGK1) inhibitors.

    Science.gov (United States)

    Hammond, Marlys; Washburn, David G; Hoang, H Tram; Manns, Sharada; Frazee, James S; Nakamura, Hiroko; Patterson, Jaclyn R; Trizna, Walter; Wu, Charlene; Azzarano, Leonard M; Nagilla, Rakesh; Nord, Melanie; Trejo, Rebecca; Head, Martha S; Zhao, Baoguang; Smallwood, Angela M; Hightower, Kendra; Laping, Nicholas J; Schnackenberg, Christine G; Thompson, Scott K

    2009-08-01

    The lead serum and glucocorticoid-related kinase 1 (SGK1) inhibitors 4-(5-phenyl-1H-pyrrolo[2,3-b]pyridin-3-yl)benzoic acid (1) and {4-[5-(2-naphthalenyl)-1H-pyrrolo[2,3-b]pyridin-3-yl]phenyl}acetic acid (2) suffer from low DNAUC values in rat, due in part to formation and excretion of glucuronic acid conjugates. These PK/glucuronidation issues were addressed either by incorporating a substituent on the 3-phenyl ring ortho to the key carboxylate functionality of 1 or by substituting on the group in between the carboxylate and phenyl ring of 2. Three of these analogs have been identified as having good SGK1 inhibition potency and have DNAUC values suitable for in vivo testing.

  1. The effect of cyclin-dependent kinases inhibitor treatment on experimental herpes simplex encephalitis mice.

    Science.gov (United States)

    Zhou, Yu; Zeng, Yan-Ping; Zhou, Qin; Guan, Jing-Xia; Lu, Zu-Neng

    2016-08-01

    Herpes simplex encephalitis(HSE) is the most common and serious viral encephalitis in humans. There is a lack of effective medication to date for HSE. A better understanding of the mediators of tissue damage is essential for finding new targets for therapeutic intervention. In this project, we explored the effect of cyclin-dependent kinases inhibitor olomoucine treatment on experimental HSE mice. The following results were obtained: (1) olomoucine increased survival in HSE mice; (2) olomoucine inhibited microglial activation and reduced HSV-1-induced cytokines release; (3) olomoucine prevented neural cells apoptosis and attenuated brain tissue pathological changes following HSV-1 infection; (4) olomoucine reduced brain edema and improved neurological function in HSE. Overall, olomoucine can induce a blunted inflammatory response, maintain the blood vessel wall intact, improve neurological function and increase survival in HSE mice.

  2. A kinase inhibitor screen identifies Mcl-1 and Aurora kinase A as novel treatment targets in antiestrogen-resistant breast cancer cells

    DEFF Research Database (Denmark)

    Thrane, S; Pedersen, A M; Thomsen, M B H;

    2015-01-01

    tamoxifen- and fulvestrant-resistant cell lines. Our focus was to identify common and distinct molecular mechanisms involved in tamoxifen- and fulvestrant-resistant cell growth. We identified 18 inhibitors, of which the majority was common for both tamoxifen- and fulvestrant-resistant cell lines. Two...... compounds, WP1130 and JNJ-7706621, exhibiting prominent preferential growth inhibition of antiestrogen-resistant cell lines, were selected for further studies. WP1130, a deubiquitinase inhibitor, induced caspase-mediated cell death in both tamoxifen- and fulvestrant-resistant cell lines by destabilization...... cell cycle arrest of the tamoxifen-resistant cell lines. Knockdown studies showed that Aurora kinase A is essential for growth of the tamoxifen-resistant cells and inhibition of Aurora kinase A resensitized tamoxifen-resistant cells to tamoxifen treatment. Preferential growth inhibition by WP1130...

  3. Identification of a Glycogen Synthase Kinase-3[beta] Inhibitor that Attenuates Hyperactivity in CLOCK Mutant Mice

    Energy Technology Data Exchange (ETDEWEB)

    Kozikowski, Alan P.; Gunosewoyo, Hendra; Guo, Songpo; Gaisina, Irina N.; Walter, Richard L.; Ketcherside, Ariel; McClung, Colleen A.; Mesecar, Andrew D.; Caldarone, Barbara (Psychogenics); (Purdue); (UIC); (UTSMC)

    2012-05-02

    Bipolar disorder is characterized by a cycle of mania and depression, which affects approximately 5 million people in the United States. Current treatment regimes include the so-called 'mood-stabilizing drugs', such as lithium and valproate that are relatively dated drugs with various known side effects. Glycogen synthase kinase-3{beta} (GSK-3{beta}) plays a central role in regulating circadian rhythms, and lithium is known to be a direct inhibitor of GSK-3{beta}. We designed a series of second generation benzofuran-3-yl-(indol-3-yl)maleimides containing a piperidine ring that possess IC{sub 50} values in the range of 4 to 680 nM against human GSK-3{beta}. One of these compounds exhibits reasonable kinase selectivity and promising preliminary absorption, distribution, metabolism, and excretion (ADME) data. The administration of this compound at doses of 10 to 25 mg kg{sup -1} resulted in the attenuation of hyperactivity in amphetamine/chlordiazepoxide-induced manic-like mice together with enhancement of prepulse inhibition, similar to the effects found for valproate (400 mg kg{sup -1}) and the antipsychotic haloperidol (1 mg kg{sup -1}). We also tested this compound in mice carrying a mutation in the central transcriptional activator of molecular rhythms, the CLOCK gene, and found that the same compound attenuates locomotor hyperactivity in response to novelty. This study further demonstrates the use of inhibitors of GSK-3{beta} in the treatment of manic episodes of bipolar/mood disorders, thus further validating GSK-3{beta} as a relevant therapeutic target in the identification of new therapies for bipolar patients.

  4. Tamoxifen and Src kinase inhibitors as neuroprotective/neuroregenerative drugs after spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Iris K Salgado; Aranza I Torrado; Jose M Santiago; Jorge D Miranda

    2015-01-01

    Spinal cord injury (SCI) is a devastating condition that produces signiifcant changes in the life-style of patients. Many molecular and cellular events are triggered after the initial physical impact to the cord. Two major phases have been described in the ifeld of SCI: an acute phase and late phase. Most of the therapeutic strategies are focused on the late phase because this provides an opportunity to target cellular events like apoptosis, demyelination, scar formation and axonal outgrowth. In this mini-review, we will focus on two agents (tamoxifen and a Src kinase family inhibitor known as PP2) that have been shown in our laboratory to produce neuroprotective (increase cell survival) and/or regenerative (axonal outgrowth) actions. The animal model used in our laboratory is adult female rat (~250 g) with a moderate contusion (12.5 mm) to the spinal cord at the T10 level, using the MASCIS impactor device. Tamoxifen or PP2 was administered by implantation of a 15 mg pellet (Innovative Research of America, Sarasota, FL, USA) or by intraperitoneal injections (1.5 mg/kg, every 3 days), respectively, to produce a long-term effect (28 days). Tamoxifen and the Src kinase inhibitor, PP2, are drugs that in rats with a moderate spinal cord injury promote functional locomotor recovery, increase spared white matter tissue, and stimulate axonal outgrowth. Moreover, tamoxifen reduces the formation of reactive oxygen species. Therefore, these drugs are possible therapeutic agents that have a neuroprotective/regen-erative activity in vertebrates with SCI.

  5. Causal reasoning identifies mechanisms of sensitivity for a novel AKT kinase inhibitor, GSK690693

    Directory of Open Access Journals (Sweden)

    Macoritto Michael

    2010-07-01

    Full Text Available Abstract Background Inappropriate activation of AKT signaling is a relatively common occurrence in human tumors, and can be caused by activation of components of, or by loss or decreased activity of inhibitors of, this signaling pathway. A novel, pan AKT kinase inhibitor, GSK690693, was developed in order to interfere with the inappropriate AKT signaling seen in these human malignancies. Causal network modeling is a systematic computational analysis that identifies upstream changes in gene regulation that can serve as explanations for observed changes in gene expression. In this study, causal network modeling is employed to elucidate mechanisms of action of GSK690693 that contribute to its observed biological effects. The mechanism of action of GSK690693 was evaluated in multiple human tumor cell lines from different tissues in 2-D cultures and xenografts using RNA expression and phosphoproteomics data. Understanding the molecular mechanism of action of novel targeted agents can enhance our understanding of various biological processes regulated by the intended target and facilitate their clinical development. Results Causal network modeling on transcriptomic and proteomic data identified molecular networks that are comprised of activated or inhibited mechanisms that could explain observed changes in the sensitive cell lines treated with GSK690693. Four networks common to all cell lines and xenografts tested were identified linking GSK690693 inhibition of AKT kinase activity to decreased proliferation. These networks included increased RB1 activity, decreased MYC activity, decreased TFRC activity, and increased FOXO1/FOXO3 activity. Conclusion AKT is involved in regulating both cell proliferation and apoptotic pathways; however, the primary effect with GSK690693 appears to be anti-proliferative in the cell lines and xenografts evaluated. Furthermore, these results indicate that anti-proliferative responses to GSK690693 in either 2-D culture or

  6. KDR activating mutations in human angiosarcomas are sensitive to specific kinase inhibitors.

    Science.gov (United States)

    Antonescu, Cristina R; Yoshida, Akihiko; Guo, Tianhuo; Chang, Ning-En; Zhang, Lei; Agaram, Narasimhan P; Qin, Li-Xuan; Brennan, Murray F; Singer, Samuel; Maki, Robert G

    2009-09-15

    Angiosarcomas (AS) represent a heterogeneous group of malignant vascular tumors occurring not only in different anatomic locations but also in distinct clinical settings, such as radiation or associated chronic lymphedema. Although representing only 1% to 2% of soft tissue sarcomas, vascular sarcomas provide unique insight into the general process of tumor angiogenesis. However, no molecular candidates have been identified to guide a specific therapeutic intervention. By expression profiling, AS show distinct up-regulation of vascular-specific receptor tyrosine kinases, including TIE1, KDR, SNRK, TEK, and FLT1. Full sequencing of these five candidate genes identified 10% of patients harboring KDR mutations. A KDR-positive genotype was associated with strong KDR protein expression and was restricted to the breast anatomic site with or without prior exposure to radiation. Transient transfection of KDR mutants into COS-7 cells showed ligand-independent activation of the kinase, which was inhibited by specific KDR inhibitors. These data provide a basis for the activity of vascular endothelial growth factor receptor-directed therapy in the treatment of primary and radiation-induced AS. PMID:19723655

  7. Gold nanoparticles enhance the effect of tyrosine kinase inhibitors in acute myeloid leukemia therapy

    Science.gov (United States)

    Petrushev, Bobe; Boca, Sanda; Simon, Timea; Berce, Cristian; Frinc, Ioana; Dima, Delia; Selicean, Sonia; Gafencu, Grigore-Aristide; Tanase, Alina; Zdrenghea, Mihnea; Florea, Adrian; Suarasan, Sorina; Dima, Liana; Stanciu, Raluca; Jurj, Ancuta; Buzoianu, Anca; Cucuianu, Andrei; Astilean, Simion; Irimie, Alexandru; Tomuleasa, Ciprian; Berindan-Neagoe, Ioana

    2016-01-01

    Background and aims Every year, in Europe, acute myeloid leukemia (AML) is diagnosed in thousands of adults. For most subtypes of AML, the backbone of treatment was introduced nearly 40 years ago as a combination of cytosine arabinoside with an anthracycline. This therapy is still the worldwide standard of care. Two-thirds of patients achieve complete remission, although most of them ultimately relapse. Since the FLT3 mutation is the most frequent, it serves as a key molecular target for tyrosine kinase inhibitors (TKIs) that inhibit FLT3 kinase. In this study, we report the conjugation of TKIs onto spherical gold nanoparticles. Materials and methods The internalization of TKI-nanocarriers was proved by the strongly scattered light from gold nanoparticles and was correlated with the results obtained by transmission electron microscopy and dark-field microscopy. The therapeutic effect of the newly designed drugs was investigated by several methods including cell counting assay as well as the MTT assay. Results We report the newly described bioconjugates to be superior when compared with the drug alone, with data confirmed by state-of-the-art analyses of internalization, cell biology, gene analysis for FLT3-IDT gene, and Western blotting to assess degradation of the FLT3 protein. Conclusion The effective transmembrane delivery and increased efficacy validate its use as a potential therapeutic. PMID:26929621

  8. 有丝分裂关键激酶抑制剂的研究进展%Progress on the research of key kinase inhibitors in mitosis

    Institute of Scientific and Technical Information of China (English)

    陈葆峰; 解鸿波; 沙宇; 程卯生

    2012-01-01

    目的 综述有丝分裂关键激酶抑制剂近年来的研究进展.方法 根据已报道的有丝分裂中关键激酶抑制剂的文献,将对有丝分裂过程中与肿瘤发生联系密切的激酶抑制剂,如Aurora激酶抑制剂、CDK(cyclin-dependent kinase)激酶抑制剂、PLK(Polo-like kinase)激酶抑制剂、CHK(check-point kinase)激酶抑制剂等目前的研究进展进行综述.结果 有丝分裂关键激酶抑制剂已在临床前研究及临床研究中显示出很好的抗肿瘤活性.结论 随着研究的不断深入,有丝分裂关键激酶抑制剂将在肿瘤治疗中发挥更大的作用.%Objective To review the recent progress on the research of key kinase inhibitors in mitosis. Methods According to the references to the key kinase inhibitors in mitosis reported, the kinase inhibitors were introduced closely related to the occurrence of the cancer in the progress of mitosis, such as Aurora kinase in- . hibitors, CDK (cyclin-dependent kinase) inhibitors, PLK (Polo-like kinase) inhibitors and CHK (checkpoint kinase)inhibitors. Results The potent anti-tumor activity of key kinase inhibitors in mitosis had been revealed in the preclinical and clinical research. Conclusions With the further research,key kinase inhibitors in mitosis shows more significant roles in the therapy of cancer.

  9. G-749, a novel FLT3 kinase inhibitor, can overcome drug resistance for the treatment of acute myeloid leukemia

    OpenAIRE

    Lee, Hee Kyu; Kim, Hong Woo; Lee, In Yong; Lee, Jungmi; Lee, Jaekyoo; Jung, Dong Sik; Lee, Sang Yeop; Park, Sung Ho; Hwang, Haejun; Choi, Jang-Sik; Kim, Jung-Ho; Kim, Se Won; Kim, Jung Keun; Cools, Jan; Koh, Jong Sung

    2014-01-01

    A novel inhibitor G-749 is very potent against FLT3 kinase mutants including D835Y and ITD/F691L that confer resistance to PKC412 and AC220.G-749 shows several desirable characteristics to overcome other drug resistances conferred by patient plasma, FLT3 ligand, and stromal cells.

  10. Dithiocarbamate promoted practical synthesis of N-Aryl-2-aminobenzazoles: Synthesis of novel Aurora-A kinase inhibitor

    Indian Academy of Sciences (India)

    Naresh Kumar Katari; M Venkatanarayana; Kummari Srinivas

    2015-03-01

    Various N-aryl-2-aminobenzoxazoles and N-aryl-2-aminobenzothiazoles were synthesized from o-aminophenol and o-aminothiophenol, respectively, mediated by dithiocarbamate in one step. The salient features of this method include mild reaction condition, high yield and large scale synthesis. Application of this methodology has been demonstrated by synthesizing potent Aurora kinase-A inhibitors.

  11. Rho kinase inhibitors Y27632 and H1152 augment neurite extension in the presence of cultured Schwann cells

    Directory of Open Access Journals (Sweden)

    Stark G Björn

    2008-09-01

    Full Text Available Abstract Background RhoA and Rho kinase inhibitors overcome the inhibition of axonal regeneration posed by central nervous system (CNS substrates. Methods To investigate if inhibition of the Rho pathway augments the neurite extension that naturally occurs in the peripheral nervous system (PNS following nerve damage, dorsal root ganglion neurons and Schwann cell co-cultures were incubated with culture medium, C3 fusion toxin, and the Rho kinase (ROCK inhibitors Y27632 and H1152. The longest neurite per neuron were measured and compared. Incubation with Y27632 and H1152 resulted in significantly longer neurites than controls when the neurons were in contact with Schwann cells. When separated by a porous P.E.T. membrane, only the group incubated with H1152 developed significantly longer neurites. This work demonstrates that Rho kinase inhibition augments neurite elongation in the presence of contact with a PNS-like substrate.

  12. Discovery and Optimization of Macrocyclic Quinoxaline-pyrrolo-dihydropiperidinones as Potent Pim-1/2 Kinase Inhibitors.

    Science.gov (United States)

    Cee, Victor J; Chavez, Frank; Herberich, Bradley; Lanman, Brian A; Pettus, Liping H; Reed, Anthony B; Wu, Bin; Wurz, Ryan P; Andrews, Kristin L; Chen, Jie; Hickman, Dean; Laszlo, Jimmy; Lee, Matthew R; Guerrero, Nadia; Mattson, Bethany K; Nguyen, Yen; Mohr, Christopher; Rex, Karen; Sastri, Christine E; Wang, Paul; Wu, Qiong; Wu, Tian; Xu, Yang; Zhou, Yihong; Winston, Jeffrey T; Lipford, J Russell; Tasker, Andrew S; Wang, Hui-Ling

    2016-04-14

    The identification of Pim-1/2 kinase overexpression in B-cell malignancies suggests that Pim kinase inhibitors will have utility in the treatment of lymphoma, leukemia, and multiple myeloma. Starting from a moderately potent quinoxaline-dihydropyrrolopiperidinone lead, we recognized the potential for macrocyclization and developed a series of 13-membered macrocycles. The structure-activity relationships of the macrocyclic linker were systematically explored, leading to the identification of 9c as a potent, subnanomolar inhibitor of Pim-1 and -2. This molecule also potently inhibited Pim kinase activity in KMS-12-BM, a multiple myeloma cell line with relatively high endogenous levels of Pim-1/2, both in vitro (pBAD IC50 = 25 nM) and in vivo (pBAD EC50 = 30 nM, unbound), and a 100 mg/kg daily dose was found to completely arrest the growth of KMS-12-BM xenografts in mice.

  13. Caveolin-1 Up-regulation during Epithelial to Mesenchymal Transition Is Mediated by Focal Adhesion Kinase*

    OpenAIRE

    Bailey, Kelly M.; Liu, Jun

    2008-01-01

    Emerging evidence has shown that caveolin-1 is up-regulated in a number of metastatic cancers and can influence various aspects of cell migration. However, in general, the role of caveolin-1 in cancer progression is poorly understood. In the present study, we examined alterations in caveolin-1 expression during epithelial-to-mesenchymal transition (EMT) and the ability of caveolin-1 to alter cancer cell adhesion, an aspect of cell motility. We employed two EMT cell models, the human embryonic...

  14. Dermatologic Toxicities from Monoclonal Antibodies and Tyrosine Kinase Inhibitors against EGFR: Pathophysiology and Management

    Directory of Open Access Journals (Sweden)

    Shaad E. Abdullah

    2012-01-01

    Full Text Available Epidermal growth factor receptor (EGFR inhibition has now been well established as an effective treatment for various cancers. The EGFR belongs to the ErbB family of tyrosine kinase receptors which regulate tumor cell differentiation, survival and proliferation. Activation of EGFR drives tumorigenesis in lung, head and neck, colorectal and pancreatic cancers. Irrespective of the type of cancer being treated and the mechanism by which tumor EGFR drives tumorigenesis, the major side effect of EGFR inhibition is a papulopustular (also described as maculopapular or acneiform rash which occurs in about two thirds of treated patients. Interestingly, this rash has been commonly correlated with better clinical outcomes (objective tumor response and patient survival. The pathophysiology of dermatological toxicity from EGFR inhibitors is an important area of clinical research, and the proper management of the rash is essential to increase the therapeutic index from this class of drugs. In this paper, we review the dermatologic toxicities associated with EGFR inhibitors with an emphasis on its pathophysiology and clinical management.

  15. [MORPHOFUNCTIONAL STATE OF BLOOD CELLS AFTER CHRONIC EXPOSURE OF THE PROTEIN KINASES INHIBITOR MALEIMIDE DERIVATIVE].

    Science.gov (United States)

    Byelinska, I V; Lynchak, O V; Tsyvinska, S M; Rybalchenko, V K

    2015-01-01

    The effect of the protein kinases inhibitor maleimide derivative (MI-1, 1-(4-Cl-benzyl)-3-Cl-4-(CF3-phenylamino)-1H-pyrrole-2,5-dione), inhibitor of VEGF-R1,2,3, FGF-R1, EGF-R(h), PDK1, Src(h), Syk(h), YES, ZAP70 et al. with antineoplastic activity, on blood cells parameters of rats after chronic exposure has been studied. Administration of MI-1 at doses 0.027 and 2.7 mg/kg (suppress colon carcinogenesis) for 20 and 26 weeks does not affect the morphofunctional state of red blood cells in healthy rats. This is confirmed by the lack of differences in the concentration of hemoglobin in blood, red blood cells count, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration, hematocrit and mean corpuscular volume, and the number of reticulocytes in blood after 20 and 26 weeks of exposure compared with the control group. MI-1 at indicated doses does not influence total leukocytes count and content (eosinophilic and neutrophilic granulocytes, lymphocytes, monocytes) and does not inhibit thrombocytopoiesis (platelet count remains unchanged). No negative effect of MI-1 on hematopoiesis is not limited (by the hemopoietic system) use of this compound as a potential antitumor drug PMID:26552308

  16. Fasudil, a Rho-Kinase Inhibitor, Attenuates Bleomycin-Induced Pulmonary Fibrosis in Mice

    Directory of Open Access Journals (Sweden)

    Zuojun Xu

    2012-07-01

    Full Text Available The mechanisms underlying the pathogenesis of idiopathic pulmonary fibrosis (IPF involve multiple pathways, such as inflammation, epithelial mesenchymal transition, coagulation, oxidative stress, and developmental processes. The small GTPase, RhoA, and its target protein, Rho-kinase (ROCK, may interact with other signaling pathways known to contribute to pulmonary fibrosis. This study aimed to determine the beneficial effects and mechanisms of fasudil, a selective ROCK inhibitor, on bleomycin-induced pulmonary fibrosis in mice. Our results showed that the Aschcroft score and hydroxyproline content of the bleomycin-treated mouse lung decreased in response to fasudil treatment. The number of infiltrated inflammatory cells in the bronchoalveolar lavage fluid (BALF was attenuated by fasudil. In addition, fasudil reduced the production of transforming growth factor-β1 (TGF-β1, connective tissue growth factor (CTGF, alpha-smooth muscle actin (α-SMA, and plasminogen activator inhibitor-1 (PAI-1 mRNA and protein expression in bleomycin-induced pulmonary fibrosis. These findings suggest that fasudil may be a potential therapeutic candidate for the treatment of pulmonary fibrosis.

  17. Review : Third Generation Tyrosine Kinase Inhibitors and Their Development in Advanced Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Ronald M Bukowski

    2012-02-01

    Full Text Available Angiogenesis in general and the VEGF signaling axis in particular is a validated target in renal cell carcinoma. Clear cell carcinoma of the kidney is now recognized as a malignancy that is sensitive to inhibitors of the vascular endothelial growth factor pathway. Treatment options for patients with metastatic renal cell carcinoma have evolved in dramatic fashion over the past six years, and a new paradigm has developed. The cytokines interferon-α and interleukin-2 were previously utilized for therapy, but since December 2005, six new agents have been approved in the United States for the treatment of advanced RCC. Three are tyrosine kinase inhibitors (TKI’s including sunitinib, sorafenib, and recently pazopanib. The current review examines the evolving data with the next generation of TKI’s, axitinib and tivozanib being developed for the treatment of advanced RCC. These agents were synthesized to provide increased target specificity and enhanced target inhibition. The preclinical and clinical data are examined, an overview of the development of these TKI’s is provided, and discussion plus speculation concerning their potential roles as RCC therapy is provided.

  18. Homozygous mutation of focal adhesion kinase in embryonic stem cell derived neurons: normal electrophysiological and morphological properties in vitro

    Directory of Open Access Journals (Sweden)

    Komiyama NH

    2006-06-01

    Full Text Available Abstract Background Genetically manipulated embryonic stem (ES cell derived neurons (ESNs provide a powerful system with which to study the consequences of gene manipulation in mature, synaptically connected neurons in vitro. Here we report a study of focal adhesion kinase (FAK, which has been implicated in synapse formation and regulation of ion channels, using the ESN system to circumvent the embryonic lethality of homozygous FAK mutant mice. Results Mouse ES cells carrying homozygous null mutations (FAK-/- were generated and differentiated in vitro into neurons. FAK-/- ESNs extended axons and dendrites and formed morphologically and electrophysiologically intact synapses. A detailed study of NMDA receptor gated currents and voltage sensitive calcium currents revealed no difference in their magnitude, or modulation by tyrosine kinases. Conclusion FAK does not have an obligatory role in neuronal differentiation, synapse formation or the expression of NMDA receptor or voltage-gated calcium currents under the conditions used in this study. The use of genetically modified ESNs has great potential for rapidly and effectively examining the consequences of neuronal gene manipulation and is complementary to mouse studies.

  19. ROCK inhibitor fasudil attenuated high glucose-induced MCP-1 and VCAM-1 expression and monocyte-endothelial cell adhesion

    Directory of Open Access Journals (Sweden)

    Li Hailing

    2012-06-01

    Full Text Available Abstract Background Previous studies suggested that the RhoA/ROCK pathway may contribute to vascular complications in diabetes. The present study was designed to investigate whether ROCK inhibitor fasudil could prevent high glucose-induced monocyte-endothelial cells adhesion, and whether this was related to fasudil effects on vascular endothelial cell expression of chemotactic factors, vascular cell adhesion molecule-1 (VCAM-1 and monocyte chemoattractant protein-1 (MCP-1. Methods HUVECs were stimulated with high glucose (HG or HG + fasudil in different concentration or different time. Monocyte-endothelial cell adhesion was determined using fluorescence-labeled monocytes. The mRNA and protein expression of VCAM-1 and MCP-1 were measured using real-time PCR and western blot. The protein levels of RhoA, ROCKI and p-MYPT were determined using western blot analysis. ELISA was employed to measure the expression of soluble VCAM-1 and MCP-1 in cell supernatants and human serum samples. Results Fasudil significantly suppressed HG-induced adhesion of THP-1 to HUVECs. Fasudil reduced Rho/ROCK activity (as indicated by lower p-MYPT/MYPT ratio, and prevented HG induced increases in VCAM-1 and MCP-1 mRNA and protein levels. Fasudil also decreased MCP-1 concentration in HUVEC supernatants, but increased sVCAM-1 shedding into the media. In human diabetic subjects, 2 weeks of fasudil treatment significantly decreased serum MCP-1 level from 27.9 ± 10.6 pg/ml to 13.8 ± 7.0 pg/ml (P P  Conclusions Treatment with the Rho/ROCK pathway inhibitor fasudil attenuated HG-induced monocyte-endothelial cell adhesion, possibly by reducing endothelial expression of VCAM-1 and MCP-1. These results suggest inhibition of Rho/ROCK signaling may have therapeutic potential in preventing diabetes associated vascular inflammation and atherogenesis.

  20. Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Tamm, Christoffer, E-mail: christoffer.tamm@imbim.uu.se; Galito, Sara Pijuan, E-mail: sara.pijuan@imbim.uu.se; Anneren, Cecilia, E-mail: cecilia.anneren@imbim.uu.se

    2012-02-15

    The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt in proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: Black-Right-Pointing-Pointer SFK inhibitor SU6656 induces senescence in mouse ES cells. Black-Right-Pointing-Pointer SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. Black-Right-Pointing-Pointer SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. Black-Right-Pointing-Pointer Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. Black-Right-Pointing-Pointer SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.

  1. Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

    International Nuclear Information System (INIS)

    The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt in proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: ► SFK inhibitor SU6656 induces senescence in mouse ES cells. ► SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. ► Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. ► SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.

  2. Genetic and Pharmacological Inhibition of PDK1 in Cancer Cells: Characterization of a Selective Allosteric Kinase Inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, Kumiko; Shumway, Stuart D.; Sathyanarayanan, Sriram; Chen, Albert H.; Dolinski, Brian; Xu, Youyuan; Keilhack, Heike; Nguyen, Thi; Wiznerowicz, Maciej; Li, Lixia; Lutterbach, Bart A.; Chi, An; Paweletz, Cloud; Allison, Timothy; Yan, Youwei; Munshi, Sanjeev K.; Klippel, Anke; Kraus, Manfred; Bobkova, Ekaterina V.; Deshmukh, Sujal; Xu, Zangwei; Mueller, Uwe; Szewczak, Alexander A.; Pan, Bo-Sheng; Richon, Victoria; Pollock, Roy; Blume-Jensen, Peter; Northrup, Alan; Andersen, Jannik N. (Merck)

    2013-11-20

    Phosphoinositide-dependent kinase 1 (PDK1) is a critical activator of multiple prosurvival and oncogenic protein kinases and has garnered considerable interest as an oncology drug target. Despite progress characterizing PDK1 as a therapeutic target, pharmacological support is lacking due to the prevalence of nonspecific inhibitors. Here, we benchmark literature and newly developed inhibitors and conduct parallel genetic and pharmacological queries into PDK1 function in cancer cells. Through kinase selectivity profiling and x-ray crystallographic studies, we identify an exquisitely selective PDK1 inhibitor (compound 7) that uniquely binds to the inactive kinase conformation (DFG-out). In contrast to compounds 1-5, which are classical ATP-competitive kinase inhibitors (DFG-in), compound 7 specifically inhibits cellular PDK1 T-loop phosphorylation (Ser-241), supporting its unique binding mode. Interfering with PDK1 activity has minimal antiproliferative effect on cells growing as plastic-attached monolayer cultures (i.e. standard tissue culture conditions) despite reduced phosphorylation of AKT, RSK, and S6RP. However, selective PDK1 inhibition impairs anchorage-independent growth, invasion, and cancer cell migration. Compound 7 inhibits colony formation in a subset of cancer cell lines (four of 10) and primary xenograft tumor lines (nine of 57). RNAi-mediated knockdown corroborates the PDK1 dependence in cell lines and identifies candidate biomarkers of drug response. In summary, our profiling studies define a uniquely selective and cell-potent PDK1 inhibitor, and the convergence of genetic and pharmacological phenotypes supports a role of PDK1 in tumorigenesis in the context of three-dimensional in vitro culture systems.

  3. Converting potent indeno[1,2-b]indole inhibitors of protein kinase CK2 into selective inhibitors of the breast cancer resistance protein ABCG2.

    Science.gov (United States)

    Jabor Gozzi, Gustavo; Bouaziz, Zouhair; Winter, Evelyn; Daflon-Yunes, Nathalia; Aichele, Dagmar; Nacereddine, Abdelhamid; Marminon, Christelle; Valdameri, Glaucio; Zeinyeh, Waël; Bollacke, Andre; Guillon, Jean; Lacoudre, Aline; Pinaud, Noël; Cadena, Silvia M; Jose, Joachim; Le Borgne, Marc; Di Pietro, Attilio

    2015-01-01

    A series of indeno[1,2-b]indole-9,10-dione derivatives were synthesized as human casein kinase II (CK2) inhibitors. The most potent inhibitors contained a N(5)-isopropyl substituent on the C-ring. The same series of compounds was found to also inhibit the breast cancer resistance protein ABCG2 but with totally different structure-activity relationships: a N(5)-phenethyl substituent was critical, and additional hydrophobic substituents at position 7 or 8 of the D-ring or a methoxy at phenethyl position ortho or meta also contributed to inhibition. The best ABCG2 inhibitors, such as 4c, 4h, 4i, 4j, and 4k, behaved as very weak inhibitors of CK2, whereas the most potent CK2 inhibitors, such as 4a, 4p, and 4e, displayed limited interaction with ABCG2. It was therefore possible to convert, through suitable substitutions of the indeno[1,2-b]indole-9,10-dione scaffold, potent CK2 inhibitors into selective ABCG2 inhibitors and vice versa. In addition, some of the best ABCG2 inhibitors, which displayed a very low cytotoxicity, thus giving a high therapeutic ratio, and appeared not to be transported, constitute promising candidates for further investigations.

  4. Green Tea Epigallocatechin Gallate Exhibits Anticancer Effect in Human Pancreatic Carcinoma Cells via the Inhibition of Both Focal Adhesion Kinase and Insulin-Like Growth Factor-I Receptor

    Directory of Open Access Journals (Sweden)

    Hoang Anh Vu

    2010-01-01

    Full Text Available The exact molecular mechanism by which epigallocatechin gallate (EGCG suppresses human pancreatic cancer cell proliferation is unclear. We show here that EGCG-treated pancreatic cancer cells AsPC-1 and BxPC-3 decrease cell adhesion ability on micro-pattern dots, accompanied by dephosphorylations of both focal adhesion kinase (FAK and insulin-like growth factor-1 receptor (IGF-1R whereas retained the activations of mitogen-activated protein kinase and mammalian target of rapamycin. The growth of AsPC-1 and BxPC-3 cells can be significantly suppressed by EGCG treatment alone in a dose-dependent manner. At a dose of 100 μM which completely abolishes activations of FAK and IGF-1R, EGCG suppresses more than 50% of cell proliferation without evidence of apoptosis analyzed by PARP cleavage. Finally, the MEK1/2 inhibitor U0126 enhances growth-suppressive effect of EGCG. Our data suggests that blocking FAK and IGF-1R by EGCG could prove valuable for targeted therapy, which can be used in combination with other therapies, for pancreatic cancer.

  5. Tyrosine kinase inhibitor SU6668 represses chondrosarcoma growth via antiangiogenesis in vivo

    International Nuclear Information System (INIS)

    As chondrosarcomas are resistant to chemotherapy and ionizing radiation, therapeutic options are limited. Radical surgery often cannot be performed. Therefore, additional therapies such as antiangiogenesis represent a promising strategy for overcoming limitations in chondrosarcoma therapy. There is strong experimental evidence that SU6668, an inhibitor of the angiogenic tyrosine kinases Flk-1/KDR, PDGFRbeta and FGFR1 can induce growth inhibition of various primary tumors. However, the effectiveness of SU6668 on malignant primary bone tumors such as chondrosarcomas has been rarely investigated. Therefore, the aim of this study was to investigate the effects of SU6668 on chondrosarcoma growth, angiogenesis and microcirculation in vivo. In 10 male severe combined immunodeficient (SCID) mice, pieces of SW1353 chondrosarcomas were implanted into a cranial window preparation where the calvaria serves as the site for the orthotopic implantation of bone tumors. From day 7 after tumor implantation, five animals were treated with SU6668 (250 mg/kg body weight, s.c.) at intervals of 48 hours (SU6668), and five animals with the equivalent amount of the CMC-based vehicle (Control). Angiogenesis, microcirculation, and growth of SW 1353 tumors were analyzed by means of intravital microscopy. SU6668 induced a growth arrest of chondrosarcomas within 7 days after the initiation of the treatment. Compared to Controls, SU6668 decreased functional vessel density and tumor size, respectively, by 37% and 53% on day 28 after tumor implantation. The time course of the experiments demonstrated that the impact on angiogenesis preceded the anti-tumor effect. Histological and immunohistochemical results confirmed the intravital microscopy findings. SU6668 is a potent inhibitor of chondrosarcoma tumor growth in vivo. This effect appears to be induced by the antiangiogenic effects of SU6668, which are mediated by the inhibition of the key angiogenic receptor tyrosine kinases Flk-1/KDR, PDGFRbeta

  6. Combined therapeutic potential of nuclear receptors with receptor tyrosine kinase inhibitors in lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wairagu, Peninah M. [Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Institute of Lifestyle Medicine, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Nuclear Receptor Research Consortium, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Park, Kwang Hwa [Department of Pathology, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Kim, Jihye [Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Institute of Lifestyle Medicine, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Nuclear Receptor Research Consortium, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Choi, Jong-Whan; Kim, Hyun-Won; Yeh, Byung-Il [Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Jung, Soon-Hee [Department of Pathology, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Yong, Suk-Joong [Department of Internal Medicine, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Jeong, Yangsik, E-mail: yjeong@yonsei.ac.kr [Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Institute of Lifestyle Medicine, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of); Nuclear Receptor Research Consortium, Wonju College of Medicine, Yonsei University, Wonju, Gangwon-do 220-701 (Korea, Republic of)

    2014-05-09

    Highlights: • The 48 NR genes and 48 biological anti-cancer targets are profiled in paired-cells. • Growth inhibition by NR ligands or TKIs is target receptor level-dependent. • T0901317 with gefitinib/PHA665752 shows additive growth inhibition in lung cells. - Abstract: Cancer heterogeneity is a big hurdle in achieving complete cancer treatment, which has led to the emergence of combinational therapy. In this study, we investigated the potential use of nuclear receptor (NR) ligands for combinational therapy with other anti-cancer drugs. We first profiled all 48 NRs and 48 biological anti-cancer targets in four pairs of lung cell lines, where each pair was obtained from the same patient. Two sets of cell lines were normal and the corresponding tumor cell lines while the other two sets consisted of primary versus metastatic tumor cell lines. Analysis of the expression profile revealed 11 NRs and 15 cancer targets from the two pairs of normal versus tumor cell lines, and 9 NRs and 9 cancer targets from the primary versus metastatic tumor cell lines had distinct expression patterns in each category. Finally, the evaluation of nuclear receptor ligand T0901317 for liver X receptor (LXR) demonstrated its combined therapeutic potential with tyrosine kinase inhibitors. The combined treatment of cMET inhibitor PHA665752 or EGFR inhibitor gefitinib with T0901317 showed additive growth inhibition in both H2073 and H1993 cells. Mechanistically, the combined treatment suppressed cell cycle progression by inhibiting cyclinD1 and cyclinB expression. Taken together, this study provides insight into the potential use of NR ligands in combined therapeutics with other biological anti-cancer drugs.

  7. Combined therapeutic potential of nuclear receptors with receptor tyrosine kinase inhibitors in lung cancer

    International Nuclear Information System (INIS)

    Highlights: • The 48 NR genes and 48 biological anti-cancer targets are profiled in paired-cells. • Growth inhibition by NR ligands or TKIs is target receptor level-dependent. • T0901317 with gefitinib/PHA665752 shows additive growth inhibition in lung cells. - Abstract: Cancer heterogeneity is a big hurdle in achieving complete cancer treatment, which has led to the emergence of combinational therapy. In this study, we investigated the potential use of nuclear receptor (NR) ligands for combinational therapy with other anti-cancer drugs. We first profiled all 48 NRs and 48 biological anti-cancer targets in four pairs of lung cell lines, where each pair was obtained from the same patient. Two sets of cell lines were normal and the corresponding tumor cell lines while the other two sets consisted of primary versus metastatic tumor cell lines. Analysis of the expression profile revealed 11 NRs and 15 cancer targets from the two pairs of normal versus tumor cell lines, and 9 NRs and 9 cancer targets from the primary versus metastatic tumor cell lines had distinct expression patterns in each category. Finally, the evaluation of nuclear receptor ligand T0901317 for liver X receptor (LXR) demonstrated its combined therapeutic potential with tyrosine kinase inhibitors. The combined treatment of cMET inhibitor PHA665752 or EGFR inhibitor gefitinib with T0901317 showed additive growth inhibition in both H2073 and H1993 cells. Mechanistically, the combined treatment suppressed cell cycle progression by inhibiting cyclinD1 and cyclinB expression. Taken together, this study provides insight into the potential use of NR ligands in combined therapeutics with other biological anti-cancer drugs

  8. A platinum-based hybrid drug design approach to circumvent acquired resistance to molecular targeted tyrosine kinase inhibitors

    Science.gov (United States)

    Wei, Yuming; Poon, Daniel C.; Fei, Rong; Lam, Amy S. M.; Au-Yeung, Steve C. F.; To, Kenneth K. W.

    2016-05-01

    Three molecular targeted tyrosine kinase inhibitors (TKI) were conjugated to classical platinum-based drugs with an aim to circumvent TKI resistance, predominately mediated by the emergence of secondary mutations on oncogenic kinases. The hybrids were found to maintain specificity towards the same oncogenic kinases as the original TKI. Importantly, they are remarkably less affected by TKI resistance, presumably due to their unique structure and the observed dual mechanism of anticancer activity (kinase inhibition and DNA damage). The study is also the first to report the application of a hybrid drug approach to switch TKIs from being efflux transporter substrates into non-substrates. TKIs cannot penetrate into the brain for treating metastases because of efflux transporters at the blood brain barrier. The hybrids were found to escape drug efflux and they accumulate more than the original TKI in the brain in BALB/c mice. Further development of the hybrid compounds is warranted.

  9. Structural basis for specificity and potency of a flavonoid inhibitor of human CDK2, a cell cycle kinase

    Energy Technology Data Exchange (ETDEWEB)

    Filgueira de Azevedo, W. Jr.; Mueller-Dieckmann, H.J.; Schulze-Gahmen, U. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1996-04-02

    The central role of cyclin-dependent kinases (CDKs) in cell cycle regulation makes them a promising target for studying inhibitory molecules that can modify the degree of cell proliferation. The discovery of specific inhibitors of CDKs such as polyhydroxylated flavones has opened the way to investigation and design of antimitotic compounds. A novel flavone, (-)-cis-5,7-dihydroxyphenyl-8-[4-(3-hydroxy-1-methyl)piperidinyl]-4H-1-benzopyran-4-one hydrochloride hemihydrate (L868276), is a potent inhibitor of CDKs. A chlorinated form, flavopiridol, is currently in phase I clinical trials as a drug against breast tumors. We determined the crystal structure of a complex between CDK2 and L868276 at 2.33-{Angstrom} resolution and refined to an R{sub factor} of 20.3%. The aromatic portion of the inhibitor binds to the adenine-binding pocket of CDK2, and the position of the phenyl group of the inhibitor enables the inhibitor to make contacts with the enzyme not observed in the ATP complex structure. The analysis of the position of this phenyl ring not only explains the great differences of kinase inhibition among the flavonoid inhibitors but also explains the specificity of L868276 to inhibit CDK2 and CDC2. 36 refs., 4 figs., 2 tabs.

  10. Discovery of a novel allosteric inhibitor-binding site in ERK5: comparison with the canonical kinase hinge ATP-binding site.

    Science.gov (United States)

    Chen, Hongming; Tucker, Julie; Wang, Xiaotao; Gavine, Paul R; Phillips, Chris; Augustin, Martin A; Schreiner, Patrick; Steinbacher, Stefan; Preston, Marian; Ogg, Derek

    2016-05-01

    MAP kinases act as an integration point for multiple biochemical signals and are involved in a wide variety of cellular processes such as proliferation, differentiation, regulation of transcription and development. As a member of the MAP kinase family, ERK5 (MAPK7) is involved in the downstream signalling pathways of various cell-surface receptors, including receptor tyrosine kinases and G protein-coupled receptors. In the current study, five structures of the ERK5 kinase domain co-crystallized with ERK5 inhibitors are reported. Interestingly, three of the compounds bind at a novel allosteric binding site in ERK5, while the other two bind at the typical ATP-binding site. Binding of inhibitors at the allosteric site is accompanied by displacement of the P-loop into the ATP-binding site and is shown to be ATP-competitive in an enzymatic assay of ERK5 kinase activity. Kinase selectivity data show that the most potent allosteric inhibitor exhibits superior kinase selectivity compared with the two inhibitors that bind at the canonical ATP-binding site. An analysis of these structures and comparison with both a previously published ERK5-inhibitor complex structure (PDB entry 4b99) and the structures of three other kinases (CDK2, ITK and MEK) in complex with allosteric inhibitors are presented.

  11. Protein Kinase Inhibitor H89 Enhances the Activity of Pseudomonas Exotoxin A-Based Immunotoxins.

    Science.gov (United States)

    Liu, Xiufen; Müller, Fabian; Wayne, Alan S; Pastan, Ira

    2016-05-01

    HA22 (Moxetumomab pasudotox) is a recombinant immunotoxin (RIT), composed of an anti-CD22 Fv fused to a truncated portion of Pseudomonas exotoxin A. HA22 is in clinical trials to treat patients with hairy cell leukemia and acute lymphoblastic leukemia (ALL). LMB-11 is an improved variant of HA22 with reduced immunogenicity, has a longer half-life in the blood and high activity in vitro and in a Burkitt lymphoma model in vivo Searching for RIT enhancing combination therapies, we found the protein kinase A inhibitor H89 to enhance LMB-11 and HA22 activity 5- to 10-fold on ALL cell lines and on patient-derived ALL samples. In addition, H89 increased the activity of mesothelin-targeting RITs SS1P (38-fold) and RG7787 (7-fold) against the cervical cancer cell line KB31. Unexpectedly we found that the enhancement by H89 was not because of inhibition of protein kinase A; it was partially recapitulated by inhibition of S6K1, which led to inactivation of its downstream targets rpS6 and GSK3β, resulting in a fall in MCL1 levels. H89 increased the rate of ADP-ribosylation of eukaryotic elongation factor 2, enhancing the arrest of protein synthesis and the reduction of MCL1 in synergy with the RIT. In summary, H89 increased RIT activity by enhancing the two key events: ADP-ribosylation of eEF2 and reduction of MCL1 levels. Significant enhancement was seen with both CD22- and mesothelin-targeting RITs, indicating that H89 might be a potent addition to RIT treatment of CD22-positive ALL and mesothelin-expressing solid tumors. Mol Cancer Ther; 15(5); 1053-62. ©2016 AACR. PMID:26939705

  12. Mechanisms of acquired resistance to EGFR-tyrosine kinase inhibitor in Korean patients with lung cancer

    International Nuclear Information System (INIS)

    Despite an initial good response to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), resistance to treatment eventually develops. Although several resistance mechanisms have been discovered, little data exist regarding Asian patient populations. Among patients at a tertiary referral hospital in Korea who initially responded well to gefitinib and later acquired resistance to treatment, we selected those with enough tissues obtained before EGFR-TKI treatment and after the onset of resistance to examine mutations by mass spectrometric genotyping technology (Asan-Panel), MET amplification by fluorescence in situ hybridization (FISH), and analysis of AXL status, epithelial-to-mesenchymal transition (EMT) and neuroendocrine markers by immunohistochemistry. Twenty-six patients were enrolled, all of whom were diagnosed with adenocarcinoma with EGFR mutations (19del: 16, L858R: 10) except one (squamous cell carcinoma with 19del). Secondary T790M mutation was detected in 11 subjects (42.3%) and four of these patients had other co-existing resistance mechanisms; increased AXL expression was observed in 5/26 patients (19.2%), MET gene amplification was noted in 3/26 (11.5%), and one patient acquired a mutation in the phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha isoform (PIK3CA) gene. None of the patients exhibited EMT; however, increased CD56 expression suggesting neuroendocrine differentiation was observed in two patients. Interestingly, conversion from L858R-mutant to wild-type EGFR occurred in one patient. Seven patients (26.9%) did not exhibit any known resistance mechanisms. Patients with a T790M mutation showed a more favorable prognosis. The mechanisms and frequency of acquired EGFR-TKI resistance in Koreans are comparable to those observed in Western populations; however, more data regarding the mechanisms that drive EGFR-TKI resistance are necessary

  13. The susceptibility of trypanosomatid pathogens to PI3/mTOR kinase inhibitors affords a new opportunity for drug repurposing.

    Directory of Open Access Journals (Sweden)

    Rosario Diaz-Gonzalez

    2011-08-01

    Full Text Available BACKGROUND: Target repurposing utilizes knowledge of "druggable" targets obtained in one organism and exploits this information to pursue new potential drug targets in other organisms. Here we describe such studies to evaluate whether inhibitors targeting the kinase domain of the mammalian Target of Rapamycin (mTOR and human phosphoinositide-3-kinases (PI3Ks show promise against the kinetoplastid parasites Trypanosoma brucei, T. cruzi, Leishmania major, and L. donovani. The genomes of trypanosomatids encode at least 12 proteins belonging to the PI3K protein superfamily, some of which are unique to parasites. Moreover, the shared PI3Ks differ greatly in sequence from those of the human host, thereby providing opportunities for selective inhibition. METHODOLOGY/PRINCIPAL FINDINGS: We focused on 8 inhibitors targeting mTOR and/or PI3Ks selected from various stages of pre-clinical and clinical development, and tested them against in vitro parasite cultures and in vivo models of infection. Several inhibitors showed micromolar or better efficacy against these organisms in culture. One compound, NVP-BEZ235, displayed sub-nanomolar potency, efficacy against cultured parasites, and an ability to clear parasitemia in an animal model of T. brucei rhodesiense infection. CONCLUSIONS/SIGNIFICANCE: These studies strongly suggest that mammalian PI3/TOR kinase inhibitors are a productive starting point for anti-trypanosomal drug discovery. Our data suggest that NVP-BEZ235, an advanced clinical candidate against solid tumors, merits further investigation as an agent for treating African sleeping sickness.

  14. Urolithin as a converging scaffold linking ellagic acid and coumarin analogues: design of potent protein kinase CK2 inhibitors.

    Science.gov (United States)

    Cozza, Giorgio; Gianoncelli, Alessandra; Bonvini, Paolo; Zorzi, Elisa; Pasquale, Riccardo; Rosolen, Angelo; Pinna, Lorenzo A; Meggio, Flavio; Zagotto, Giuseppe; Moro, Stefano

    2011-12-01

    Casein kinase 2 (CK2) is a ubiquitous, essential, and highly pleiotropic protein kinase; its abnormally high constitutive activity is suspected to underlie its pathogenic potential in neoplasia and other relevant diseases. Previously, using different in silico screening approaches, two potent and selective CK2 inhibitors were identified by our group: ellagic acid, a naturally occurring tannic acid derivative (K(i)=20 nM) and 3,8-dibromo-7-hydroxy-4-methylchromen-2-one (DBC, K(i)=60 nM). Comparing the crystallographic binding modes of both ellagic acid and DBC, an X-ray structure-driven merging approach was taken to design novel CK2 inhibitors with improved target affinity. A urolithin moiety is proposed as a possible bridging scaffold between the two known CK2 inhibitors, ellagic acid and DBC. Optimization of urolithin A as the bridging moiety led to the identification of 4-bromo-3,8-dihydroxy-benzo[c]chromen-6-one as a novel, potent and selective CK2 inhibitor, which shows a K(i) value of 7 nM against the protein kinase, representing a significant improvement in affinity for the target compared with the two parent fragments. PMID:21972104

  15. Ca2+/calmodulin-dependent kinase II contributes to inhibitor of nuclear factor-kappa B kinase complex activation in Helicobacter pylori infection.

    Science.gov (United States)

    Maubach, Gunter; Sokolova, Olga; Wolfien, Markus; Rothkötter, Hermann-Josef; Naumann, Michael

    2013-09-15

    Helicobacter pylori, a class I carcinogen, induces a proinflammatory response by activating the transcription factor nuclear factor-kappa B (NF-κB) in gastric epithelial cells. This inflammatory condition could lead to chronic gastritis, which is epidemiologically and biologically linked to the development of gastric cancer. So far, there exists no clear knowledge on how H. pylori induces the NF-κB-mediated inflammatory response. In our study, we investigated the role of Ca(2+) /calmodulin-dependent kinase II (CAMKII), calmodulin, protein kinases C (PKCs) and the CARMA3-Bcl10-MALT1 (CBM) complex in conjunction with H. pylori-induced activation of NF-κB via the inhibitor of nuclear factor-kappa B kinase (IKK) complex. We use specific inhibitors and/or RNA interference to assess the contribution of these components. Our results show that CAMKII and calmodulin contribute to IKK complex activation and thus to the induction of NF-κB in response to H. pylori infection, but not in response to TNF-α. Thus, our findings are specific for H. pylori infected cells. Neither the PKCs α, δ, θ, nor the CBM complex itself is involved in the activation of NF-κB by H. pylori. The contribution of CAMKII and calmodulin, but not PKCs/CBM to the induction of an inflammatory response by H. pylori infection augment the understanding of the molecular mechanism involved and provide potential new disease markers for the diagnosis of gastric inflammatory diseases including gastric cancer.

  16. Differential regulation of cyclin-dependent kinase inhibitors in neuroblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Lan [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Pharmaceutical Sciences, Jilin University, Changchun 130021 (China); Paul, Pritha; Lee, Sora [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Wang, Yongsheng [Department of Pharmaceutical Sciences, Jilin University, Changchun 130021 (China); Chung, Dai H., E-mail: dai.chung@vanderbilt.edu [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States)

    2013-05-31

    Highlights: •GRP-R signaling differentially regulated the expression of p21 and p27. •Silencing GRP/GRP-R downregulated p21, while p27 expression was upregulated. •Inhibition of GRP/GRP-R signaling enhanced PTEN expression, correlative to the increased expression of p27. •PTEN and p27 co-localized in cytoplasm and silencing PTEN decreased p27 expression. -- Abstract: Gastrin-releasing peptide (GRP) and its receptor (GRP-R) are highly expressed in undifferentiated neuroblastoma, and they play critical roles in oncogenesis. We previously reported that GRP activates the PI3K/AKT signaling pathway to promote DNA synthesis and cell cycle progression in neuroblastoma cells. Conversely, GRP-R silencing induces cell cycle arrest. Here, we speculated that GRP/GRP-R signaling induces neuroblastoma cell proliferation via regulation of cyclin-dependent kinase (CDK) inhibitors. Surprisingly, we found that GRP/GRP-R differentially induced expressions of p21 and p27. Silencing GRP/GRP-R decreased p21, but it increased p27 expressions in neuroblastoma cells. Furthermore, we found that the intracellular localization of p21 and p27 in the nuclear and cytoplasmic compartments, respectively. In addition, we found that GRP/GRP-R silencing increased the expression and accumulation of PTEN in the cytoplasm of neuroblastoma cells where it co-localized with p27, thus suggesting that p27 promotes the function of PTEN as a tumor suppressor by stabilizing PTEN in the cytoplasm. GRP/GRP-R regulation of CDK inhibitors and tumor suppressor PTEN may be critical for tumoriogenesis of neuroblastoma.

  17. Thermodynamics parameters for binding of halogenated benzotriazole inhibitors of human protein kinase CK2α.

    Science.gov (United States)

    Winiewska, Maria; Kucińska, Katarzyna; Makowska, Małgorzata; Poznański, Jarosław; Shugar, David

    2015-10-01

    The interaction of human CK2α (hCK2α) with nine halogenated benzotriazoles, TBBt and its analogues representing all possible patterns of halogenation on the benzene ring of benzotriazole, was studied by biophysical methods. Thermal stability of protein-ligand complexes, monitored by calorimetric (DSC) and optical (DSF) methods, showed that the increase in the mid-point temperature for unfolding of protein-ligand complexes (i.e. potency of ligand binding to hCK2α) follow the inhibitory activities determined by biochemical assays. The dissociation constant for the ATP-hCK2α complex was estimated with the aid of microscale thermophoresis (MST) as 4.3±1.8 μM, and MST-derived dissociation constants determined for halogenated benzotriazoles, when converted according to known ATP concentrations, perfectly reconstruct IC50 values determined by the biochemical assays. Ligand-dependent quenching of tyrosine fluorescence, together with molecular modeling and DSC-derived heats of unfolding, support the hypothesis that halogenated benzotriazoles bind in at least two alternative orientations, and those that are efficient hCK2α inhibitors bind in the orientation which TBBt adopts in its complex with maize CK2α. DSC-derived apparent heat for ligand binding (ΔΔHbind) is driven by intermolecular electrostatic interactions between Lys68 and the triazole ring of the ligand, as indicated by a good correlation between ΔΔHbind and ligand pKa. Overall results, additionally supported by molecular modeling, confirm that a balance of hydrophobic and electrostatic interactions contribute predominantly (~40 kJ/mol), relative to possible intermolecular halogen/hydrogen bonding (less than 10 kJ/mol), in binding of halogenated benzotriazoles to the ATP-binding site of hCK2α. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases.

  18. Novel protein kinase D inhibitors cause potent arrest in prostate cancer cell growth and motility

    Directory of Open Access Journals (Sweden)

    Lazo John S

    2010-05-01

    Full Text Available Abstract Background Protein kinase D (PKD has been implicated in a wide range of cellular processes and pathological conditions including cancer. However, targeting PKD therapeutically and dissecting PKD-mediated cellular responses remains difficult due to lack of a potent and selective inhibitor. Previously, we identified a novel pan-PKD inhibitor, CID755673, with potency in the upper nanomolar range and high selectivity for PKD. In an effort to further enhance its selectivity and potency for potential in vivo application, small molecule analogs of CID755673 were generated by modifying both the core structure and side-chains. Results After initial activity screening, five analogs with equal or greater potencies as CID755673 were chosen for further analysis: kb-NB142-70, kb-NB165-09, kb-NB165-31, kb-NB165-92, and kb-NB184-02. Our data showed that modifications to the aromatic core structure in particular significantly increased potency while retaining high specificity for PKD. When tested in prostate cancer cells, all compounds inhibited PMA-induced autophosphorylation of PKD1, with kb-NB142-70 being most active. Importantly, these analogs caused a dramatic arrest in cell proliferation accompanying elevated cytotoxicity when applied to prostate cancer cells. Cell migration and invasion were also inhibited by these analogs with varying potencies that correlated to their cellular activity. Conclusions Throughout the battery of experiments, the compounds kb-NB142-70 and kb-NB165-09 emerged as the most potent and specific analogs in vitro and in cells. These compounds are undergoing further testing for their effectiveness as pharmacological tools for dissecting PKD function and as potential anti-cancer agents in the treatment of prostate cancer.

  19. Enhanced susceptibility of cyclin kinase inhibitor p21 knockout mice to high fat diet induced atherosclerosis

    Directory of Open Access Journals (Sweden)

    Khanna Ashwani K

    2009-07-01

    Full Text Available Abstract Cyclin kinase inhibitor p21 is one of the most potent inhibitors of aortic smooth muscle cell proliferation, a key mediator of atherosclerosis. This study tests if p2l deficiency will result in severe atherosclerosis in a mouse model. p21-/- and strain matched wild type mice were fed with high fat diet for 21 weeks. Analysis for biochemical parameters (cholesterol, triglycerides in serum and mRNA expression of CD36, HO-1, TGF-β, IFN-γ, TNF-α, PPAR-γ and NADPH oxidase components (p22phox, NOX-1 and Rac-1 was performed in aortic tissues by Real Time PCR. p21-/- mice gained significantly (p -/- compared to wild type mice fed with high fat diet. High fat diet resulted in significantly decreased TGF-β (p -/- mice compared to animal fed with regular diet. IFN-γ mRNA expression (235 ± 11 folds increased significantly in high fat diet fed p21-/- mice and a multifold modulation of PPAR-γ(136 ± 7, p22phox, NOX-1 and Rac-1 (15–35-folds mRNA in aortic tissues from p21-/- mice compared to the wild type mice. Severity of atherosclerotic lesions was significantly higher in p21-/- compared to wild type mice. The results demonstrate that the deficiency of p21 leads to altered expression of pro-atherogenic genes, and severe atherosclerosis in mice fed with high fat diet. This opens the possibility of p21 protein as a therapeutic tool to control progression of atherosclerosis.

  20. Egress of CD19+CD5+ cells into peripheral blood following treatment with the Bruton tyrosine kinase inhibitor ibrutinib in mantle cell lymphoma patients

    OpenAIRE

    Chang, Betty Y.; Francesco, Michelle; de Rooij, Martin F.M.; Magadala, Padmaja; Steggerda, Susanne M.; Huang, Min Mei; Kuil, Annemieke; Herman, Sarah E. M.; Chang, Stella; Pals, Steven T; Wilson, Wyndham; Wiestner, Adrian; Spaargaren, Marcel; Buggy, Joseph J; Elias, Laurence

    2013-01-01

    MCL cells are mobilized into the peripheral blood of patients treated with the BTK inhibitor ibrutinib.Ibrutinib dose-dependently inhibits BCR- and chemokine-mediated adhesion and migration of MCL cells.

  1. Navigating into the binding pockets of the HER family protein kinases: discovery of novel EGFR inhibitor as antitumor agent

    Directory of Open Access Journals (Sweden)

    Liu W

    2015-07-01

    Full Text Available Wei Liu,1,* Jin-Feng Ning,2,* Qing-Wei Meng,1 Jing Hu,1 Yan-Bin Zhao,1 Chao Liu,3 Li Cai11The Fourth Department of Medical Oncology, Harbin Medical University Cancer Hospital, 2The Thoracic Surgery Department, Harbin Medical University Cancer Hospital, Harbin, People’s Republic of China; 3General Surgery Department, Mudanjiang Guanliju Central Hospital, Mishan, Heilongjiang Province, People’s Republic of China*These authors contributed equally to this workAbstract: The epidermal growth factor receptor (EGFR family has been validated as a successful antitumor drug target for decades. Known EGFR inhibitors were exposed to distinct drug resistance against the various EGFR mutants within non-small-cell lung cancer (NSCLC, particularly the T790M mutation. Although so far a number of studies have been reported on the development of third-generation EGFR inhibitors for overcoming the resistance issue, the design procedure largely depends on the intuition of medicinal chemists. Here we retrospectively make a detailed analysis of the 42 EGFR family protein crystal complexes deposited in the Protein Data Bank (PDB. Based on the analysis of inhibitor binding modes in the kinase catalytic cleft, we identified a potent EGFR inhibitor (compound A-10 against drug-resistant EGFR through fragment-based drug design. This compound showed at least 30-fold more potency against EGFR T790M than the two control molecules erlotinib and gefitinib in vitro. Moreover, it could exhibit potent HER2 inhibitory activities as well as tumor growth inhibitory activity. Molecular docking studies revealed a structural basis for the increased potency and mutant selectivity of this compound. Compound A-10 may be selected as a promising candidate in further preclinical studies. In addition, our findings could provide a powerful strategy to identify novel selective kinase inhibitors on the basis of detailed kinase–ligand interaction space in the PDB.Keywords: EGFR, kinase

  2. Different Persistence of the Cellular Effects Promoted by Protein Kinase CK2 Inhibitors CX-4945 and TDB

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    Cristina Girardi

    2015-01-01

    Full Text Available We compare the cellular efficacy of two selective and cell permeable inhibitors of the antiapoptotic kinase CK2. One inhibitor, CX-4945, is already in clinical trials as antitumor drug, while the other, TDB, has been recently successfully employed to demonstrate the implication of CK2 in cellular (disregulation. We found that, upon treatment of cancer cells with these compounds, the extent of inhibition of endocellular CK2 is initially comparable but becomes significantly different after the inhibitors are removed from the cellular medium: while in CX-4945 treated cells CK2 activity is restored to control level after 24 h, in the case of TDB it is still strongly reduced after 4 days from removal. The biological effects of the two inhibitors have been analyzed by performing clonogenic, spheroid formation, and wound-healing assays: we observed a permanent inhibition of cell survival and migration in TDB-treated cells even after the inhibitor removal, while in the case of CX-4945 only its maintenance for the whole duration of the assay insured a persisting effect. We suggest that the superiority of TDB in maintaining kinase activity inhibited and perpetuating the consequent effects is an added value to be considered when planning new therapies based on CK2 targeting.

  3. Efficacy of cyclin dependent kinase 4 inhibitors as potent neuroprotective agents against insults relevant to Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Priyankar Sanphui

    Full Text Available Alzheimer's disease (AD is a progressive neurodegenerative disease with no cure till today. Aberrant activation of cell cycle regulatory proteins is implicated in neurodegenerative diseases including AD. We and others have shown that Cyclin dependent kinase 4 (Cdk4 is activated in AD brain and is required for neuron death. In this study, we tested the efficiency of commercially available Cdk4 specific inhibitors as well as a small library of synthetic molecule inhibitors targeting Cdk4 as neuroprotective agents in cellular models of neuron death. We found that several of these inhibitors significantly protected neuronal cells against death induced by nerve growth factor (NGF deprivation and oligomeric beta amyloid (Aβ that are implicated in AD. These neuroprotective agents inhibit specifically Cdk4 kinase activity, loss of mitochondrial integrity, induction of pro-apoptotic protein Bim and caspase3 activation in response to NGF deprivation. The efficacies of commercial and synthesized inhibitors are comparable. The synthesized molecules are either phenanthrene based or naphthalene based and they are synthesized by using Pschorr reaction and Buchwald coupling respectively as one of the key steps. A number of molecules of both kinds block neurodegeneration effectively. Therefore, we propose that Cdk4 inhibition would be a therapeutic choice for ameliorating neurodegeneration in AD and these synthetic Cdk4 inhibitors could lead to development of effective drugs for AD.

  4. Targeting the Metastasis Suppressor, N-Myc Downstream Regulated Gene-1, with Novel Di-2-Pyridylketone Thiosemicarbazones: Suppression of Tumor Cell Migration and Cell-Collagen Adhesion by Inhibiting Focal Adhesion Kinase/Paxillin Signaling.

    Science.gov (United States)

    Wangpu, Xiongzhi; Lu, Jiaoyang; Xi, Ruxing; Yue, Fei; Sahni, Sumit; Park, Kyung Chan; Menezes, Sharleen; Huang, Michael L H; Zheng, Minhua; Kovacevic, Zaklina; Richardson, Des R

    2016-05-01

    Metastasis is a complex process that is regulated by multiple signaling pathways, with the focal adhesion kinase (FAK)/paxillin pathway playing a major role in the formation of focal adhesions and cell motility. N-myc downstream regulated gene-1 (NDRG1) is a potent metastasis suppressor in many solid tumor types, including prostate and colon cancer. Considering the antimetastatic effect of NDRG1 and the crucial involvement of the FAK/paxillin pathway in cellular migration and cell-matrix adhesion, we assessed the effects of NDRG1 on this important oncogenic pathway. In the present study, NDRG1 overexpression and silencing models of HT29 colon cancer and DU145 prostate cancer cells were used to examine the activation of FAK/paxillin signaling and the formation of focal adhesions. The expression of NDRG1 resulted in a marked and significant decrease in the activating phosphorylation of FAK and paxillin, whereas silencing of NDRG1 resulted in an opposite effect. The expression of NDRG1 also inhibited the formation of focal adhesions as well as cell migration and cell-collagen adhesion. Incubation of cells with novel thiosemicarbazones, namely di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone and di-2-pyridylketone 4-cyclohexyl-4-methyl-3-thiosemicarbazone, that upregulate NDRG1 also resulted in decreased phosphorylation of FAK and paxillin. The ability of these thiosemicarbazones to inhibit cell migration and metastasis could be mediated, at least in part, through the FAK/paxillin pathway. PMID:26895766

  5. A chemically defined culture medium containing Rho kinase inhibitor Y-27632 for the fabrication of stratified squamous epithelial cell grafts

    Energy Technology Data Exchange (ETDEWEB)

    Aslanova, Afag [Department of Surgery, Institute of Gastroenterology, Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Institute of Advanced Biomedical Engineering and Science, Tokyo Women' s Medical University, TWIns, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Takagi, Ryo; Yamato, Masayuki; Okano, Teruo [Institute of Advanced Biomedical Engineering and Science, Tokyo Women' s Medical University, TWIns, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Yamamoto, Masakazu, E-mail: yamamoto.ige@twmu.ac.jp [Department of Surgery, Institute of Gastroenterology, Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan)

    2015-05-01

    With the development of a culture method for stratified squamous epithelial cells, tissue-engineered epithelial cell sheets have been successfully applied as clinical cell grafts. However, the implementation of these cell sheets without the use of any animal-derived materials is highly desirable. In this study, Rho-associated protein kinase inhibitor Y-27632 was used to develop a chemically defined culture medium for the fabrication of stratified epithelial cell grafts consisting of human epidermal and oral keratinocytes, and the proliferation activity, cell morphology, and gene expressions of the keratinocytes were analyzed. The results of a colorimetric assay indicated that Y-27632 significantly promoted the proliferation of the keratinocytes in culture media both with and without fetal bovine serum (FBS), although there were no indications of Y-27632 efficacy on cell morphology and stratification of the keratinocytes in culture medium without any animal-derived materials. The results of quantitative RT-PCR revealed that gene expressions correlated with cell adhesion, cell–cell junction, proliferation markers, and stem/progenitor markers in cultured keratinocytes were not strongly affected by the addition of Y-27632 to the culture medium. Moreover, gene expressions of differentiation markers in stratified keratinocytes cultured in medium without FBS were nearly identical to those of keratinocytes co-cultured with 3T3 feeder cells. Interestingly, the expressions of differentiation markers in cultured stratified keratinocytes were suppressed by FBS, whereas they were reconstructed by either co-culture of a 3T3 feeder layer or addition of Y-27632 into the culture medium containing FBS. These findings indicate that Y-27632 is a useful supplement for the development of a chemically defined culture medium for fabrication of stratified epithelial cell grafts for clinical applications for the purpose of developing the culture medium with a lower risk of pathogen

  6. A chemically defined culture medium containing Rho kinase inhibitor Y-27632 for the fabrication of stratified squamous epithelial cell grafts

    International Nuclear Information System (INIS)

    With the development of a culture method for stratified squamous epithelial cells, tissue-engineered epithelial cell sheets have been successfully applied as clinical cell grafts. However, the implementation of these cell sheets without the use of any animal-derived materials is highly desirable. In this study, Rho-associated protein kinase inhibitor Y-27632 was used to develop a chemically defined culture medium for the fabrication of stratified epithelial cell grafts consisting of human epidermal and oral keratinocytes, and the proliferation activity, cell morphology, and gene expressions of the keratinocytes were analyzed. The results of a colorimetric assay indicated that Y-27632 significantly promoted the proliferation of the keratinocytes in culture media both with and without fetal bovine serum (FBS), although there were no indications of Y-27632 efficacy on cell morphology and stratification of the keratinocytes in culture medium without any animal-derived materials. The results of quantitative RT-PCR revealed that gene expressions correlated with cell adhesion, cell–cell junction, proliferation markers, and stem/progenitor markers in cultured keratinocytes were not strongly affected by the addition of Y-27632 to the culture medium. Moreover, gene expressions of differentiation markers in stratified keratinocytes cultured in medium without FBS were nearly identical to those of keratinocytes co-cultured with 3T3 feeder cells. Interestingly, the expressions of differentiation markers in cultured stratified keratinocytes were suppressed by FBS, whereas they were reconstructed by either co-culture of a 3T3 feeder layer or addition of Y-27632 into the culture medium containing FBS. These findings indicate that Y-27632 is a useful supplement for the development of a chemically defined culture medium for fabrication of stratified epithelial cell grafts for clinical applications for the purpose of developing the culture medium with a lower risk of pathogen

  7. Tau kinase inhibitors protect hippocampal synapses despite of insoluble tau accumulation.

    Science.gov (United States)

    Hinners, Ina; Hill, Anika; Otto, Ulrike; Michalsky, Anke; Mack, Till G A; Striggow, Frank

    2008-03-01

    A better understanding of the cellular and molecular pathomechanisms of Alzheimer's disease (AD) is a prerequisite for the development of efficient treatments. We have used a novel assay system based on virus-transduced organotypic hippocampal slice cultures that mimics important aspects of tau-driven AD pathology in a short time frame. Human tau P301L, when expressed in pyramidal neurons of hippocampal slice cultures, was increasingly phosphorylated at several disease-relevant epitopes, leading to progressive neuronal dystrophy and formation of RIPA-insoluble tau. AD-like tau hyperphosphorylation was reduced by the tau kinase inhibitors lithium and SRN-003-556, but RIPA-insoluble tau remained unaffected after treatment with any of these substances. Only SRN-003-556 was able to protect hippocampal neurons from synaptic damage that was presumably caused by a toxic soluble tau fraction. These data provide first mechanistic insights towards the functional benefits of SRN-003-556 that have been observed in vivo.

  8. Electrochemical and spectrophotometric characterisation of protein kinase inhibitor and anticancer drug danusertib

    International Nuclear Information System (INIS)

    Graphical abstract: Chemical structure of danusertib and DP voltammograms recorded in 5 μM danusertib in pH = 4.5: (black curve) first and (dotted curve) second scan. - Highlights: • Clarify the redox mechanism of danusertib. • pH dependent process investigated at a glassy carbon electrode. • Number of electrons and protons determined. • Analytical determination of danusertib by voltammetry and spectrophotometry. • Different electroactive centres identified and redox mechanism proposed. - Abstract: The electrochemical oxidation mechanism of the anti-cancer drug and kinases inhibitor danusertib was studied by cyclic, differential pulse, square wave voltammetry and a glassy carbon electrode. Danusertib undergoes oxidation in a cascade mechanism and depending on the pH of the supporting electrolyte several oxidation peaks were observed. The number of electrons and protons involved in each oxidation step as well as the pKa ∼ 10.0 were determined. The analytical determination of danusertib was carried out in pH = 7.0 by square wave voltammetry with LOD = 27.4 nM and UV–VIS spectrophotometry with LOD = 0.5 μM. Different electroactive centres of danusertib were identified through comparative studies with similar compounds such as imatinib and piperazine, and an oxidation mechanism of danusertib proposed

  9. Myocardial steatosis and necrosis in atria and ventricles of rats given pyruvate dehydrogenase kinase inhibitors.

    Science.gov (United States)

    Jones, Huw Bowen; Reens, Jaimini; Johnson, Elizabeth; Brocklehurst, Simon; Slater, Ian

    2014-12-01

    Pharmaceutical therapies for non-insulin-dependent diabetes mellitus (NIDDM) include plasma glucose lowering by enhancing glucose utilization. The mitochondrial pyruvate dehydrogenase (PDH) complex is important in controlling the balance between glucose and fatty acid substrate oxidation. Administration of pyruvate dehydrogenase kinase inhibitors (PDHKIs) to rats effectively lowers plasma glucose but results in myocardial steatosis that in some instances is associated primarily with atrial and to a lesser degree with ventricular pathology. Induction of myocardial steatosis is not dose-dependent, varies from minimal to moderate severity, and is either of multifocal or diffuse distribution. Ventricular histopathology was restricted to few myocardial degenerative fibers, while that in the atrium/atria was of either acute or chronic appearance with the former showing myocardial degeneration/necrosis, acute myocarditis, edema, endothelial activation (rounding up), endocarditis, and thrombosis associated with moderate myocardial steatosis and the latter with myocardial loss, replacement fibrosis, and no apparent or minimal association with steatosis. The evidence from these evaluations indicate that excessive intramyocardial accumulation of lipid may be either primarily adverse or represents an indicator of other adversely affected cellular processes.

  10. The Tyrosine Kinase Inhibitor Sunitinib Affects Ovulation but Not Ovarian Reserve in Mouse: A Preclinical Study.

    Science.gov (United States)

    Bernard, Valérie; Bouilly, Justine; Kramer, Piet; Carré, Nadège; Schlumberger, Martin; Visser, Jenny A; Young, Jacques; Binart, Nadine

    2016-01-01

    The aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI) sunitinib, since only scarce data are available on gonadal function after this treatment. Six-week-old female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d) during 5 weeks. Fertility parameters were analyzed from ovulation to litter assessment. Sunitinib exposure significantly reduced (i) corpora lutea number per ovary (1.1 ± 0.38 in sunitinib group versus 4 ± 0.79 in control group, p<0.01) and (ii) serum Anti Müllerian hormone (AMH) levels in sunitinib treated mice (12.01 ± 1.16) compared to control mice (14.33 ± 0.87 ng/ml, p< 0.05). However, primordial and growing follicles numbers per ovary were not different in both groups. After treatment withdrawal, female mice in both groups were able to obtain litters. These data could be helpful to counsel clinicians and patients, when fertility preservation methods are discussed, before TKI treatment in girls and young women. PMID:27035144

  11. Current status of ABL tyrosine kinase inhibitors stop studies for chronic myeloid leukemia.

    Science.gov (United States)

    Kimura, Shinya

    2016-01-01

    ABL tyrosine kinase inhibitors (TKIs) dramatically improves chronic myeloid leukemia (CML) prognosis and most CML patients are now able to lead lives that are equivalent to those of healthy individuals. However, high cost to CML patients of long-term treatment and adverse effects (AEs) remain problems. At the setout, a clinical study involving the discontinuation of imatinib was conducted in France. Then, several stop studies of first-generation (imatinib) and second-generation ABL TKIs (dasatinib, nilotinib), which induce earlier response than imatinib, have also been started. These studies revealed that almost half of CML patients who are treated with ABL TKIs and achieve a certain period of sustained deep molecular response can stop ABL TKIs safely and obtain treatment free remission (TFR). AEs of ABL TKIs withdrawal and predicting factors for successful discontinuation including immunity are becoming clear gradually through these studies. It is important to conduct a comprehensive examination of the results of studies with a wide variety of protocols in order to determine which discontinuation method results in the highest probability of TFR in clinical settings. PMID:27583255

  12. Apatinib: A novel receptor tyrosine kinase inhibitor for the treatment of gastric cancer.

    Science.gov (United States)

    Roviello, Giandomenico; Ravelli, Andrea; Polom, Karol; Petrioli, Roberto; Marano, Luigi; Marrelli, Daniele; Roviello, Franco; Generali, Daniele

    2016-03-28

    Metastatic gastric cancer is a lethal disease characterized by a very short overall survival, underlining a critical need of new therapeutic options. Unfortunately, although several molecular targets have been investigated, only very few recently approved agents, such as trastuzumab in the HER2-positive setting and ramucirumab, led to a clinical improvement in the outcome of metastatic gastric cancer patients. VEGF (vascular endothelial growth factor) is one of the most potent angiogenic factors and is a signalling molecule secreted by many solid tumours. Since high VEGF expression is one of the characteristic features of gastric carcinomas, targeting VEGF is therefore considered as a promising therapeutic strategy for gastric cancer. In the scenario of possible new target therapies with particular regard to angiogenesis, apatinib is a novel receptor tyrosine kinase inhibitor selectively targeting VEGFR-2. It is an orally-bioavailable agent currently being studied in several solid tumour types showing a promising activity in gastric cancer. Due to the recent positive results as a third line of treatment for metastatic gastric cancer patients, apatinib may be an interesting and novel type of targeted treatment for metastatic gastric cancer in several lines of therapy. In this review, we summarize the available data of apatinib, mainly focused on the clinical aspect, in advanced/metastatic gastric cancer. PMID:26797419

  13. Long-term culture of human odontoma-derived cells with a Rho kinase inhibitor.

    Science.gov (United States)

    Uzawa, Katsuhiro; Kasamatsu, Atsushi; Saito, Tomoaki; Takahara, Toshikazu; Minakawa, Yasuyuki; Koike, Kazuyuki; Yamatoji, Masanobu; Nakashima, Dai; Higo, Morihiro; Sakamoto, Yosuke; Shiiba, Masashi; Tanzawa, Hideki

    2016-09-10

    Because of cellular senescence/apoptosis, no effective culture systems are available to maintain replication of cells from odontogenic tumors especially for odontoma, and, thus, the ability to isolate human odontoma-derived cells (hODCs) for functional studies is needed. The current study was undertaken to develop an approach to isolate hODCs and fully characterize the cells in vitro. The hODCs were cultured successfully with a Rho-associated protein kinase inhibitor (Y-27632) for an extended period with stabilized lengths of the telomeres to sustain a similar phenotype/property as the primary tumoral cells. While the hODCs showed stable long-term expansion with expression of major dental epithelial markers including dentin sialophosphoprotein (DSPP) even in the three-dimensional microenvironment, they lack the specific markers for the characteristics of stem cells. Moreover, cells from dental pulp showed significant up-regulation of DSPP when co-cultured with the hODCs, while control fibroblasts with the hODCs did not. Taken together, we propose that the hODCs can be isolated and expanded over the long term with Y-27632 to investigate not only the development of the hODCs but also other types of benign human tumors.

  14. The Tyrosine Kinase Inhibitor Sunitinib Affects Ovulation but Not Ovarian Reserve in Mouse: A Preclinical Study.

    Directory of Open Access Journals (Sweden)

    Valérie Bernard

    Full Text Available The aim of the study was to evaluate ovarian toxicity of tyrosine kinase inhibitor (TKI sunitinib, since only scarce data are available on gonadal function after this treatment. Six-week-old female mice received orally, once daily, vehicle or sunitinib (50 mg/kg/d during 5 weeks. Fertility parameters were analyzed from ovulation to litter assessment. Sunitinib exposure significantly reduced (i corpora lutea number per ovary (1.1 ± 0.38 in sunitinib group versus 4 ± 0.79 in control group, p<0.01 and (ii serum Anti Müllerian hormone (AMH levels in sunitinib treated mice (12.01 ± 1.16 compared to control mice (14.33 ± 0.87 ng/ml, p< 0.05. However, primordial and growing follicles numbers per ovary were not different in both groups. After treatment withdrawal, female mice in both groups were able to obtain litters. These data could be helpful to counsel clinicians and patients, when fertility preservation methods are discussed, before TKI treatment in girls and young women.

  15. Cip/Kip cyclin-dependent protein kinase inhibitors and the road to polyploidy

    Directory of Open Access Journals (Sweden)

    DePamphilis Melvin L

    2009-06-01

    Full Text Available Abstract Cyclin-dependent kinases (CDKs play a central role in the orderly transition from one phase of the eukaryotic mitotic cell division cycle to the next. In this context, p27Kip1 (one of the CIP/KIP family of CDK specific inhibitors in mammals or its functional analogue in other eukarya prevents a premature transition from G1 to S-phase. Recent studies have revealed that expression of a second member of this family, p57Kip2, is induced as trophoblast stem (TS cells differentiate into trophoblast giant (TG cells. p57 then inhibits CDK1 activity, an enzyme essential for initiating mitosis, thereby triggering genome endoreduplication (multiple S-phases without an intervening mitosis. Expression of p21Cip1, the third member of this family, is also induced in during differentiation of TS cells into TG cells where it appears to play a role in suppressing the DNA damage response pathway. Given the fact that p21 and p57 are unique to mammals, the question arises as to whether one or both of these proteins are responsible for the induction and maintenance of polyploidy during mammalian development.

  16. Discovery of Inhibitors of Trypanosoma brucei by Phenotypic Screening of a Focused Protein Kinase Library.

    Science.gov (United States)

    Woodland, Andrew; Thompson, Stephen; Cleghorn, Laura A T; Norcross, Neil; De Rycker, Manu; Grimaldi, Raffaella; Hallyburton, Irene; Rao, Bhavya; Norval, Suzanne; Stojanovski, Laste; Brun, Reto; Kaiser, Marcel; Frearson, Julie A; Gray, David W; Wyatt, Paul G; Read, Kevin D; Gilbert, Ian H

    2015-11-01

    A screen of a focused kinase inhibitor library against Trypanosoma brucei rhodesiense led to the identification of seven series, totaling 121 compounds, which showed >50 % inhibition at 5 μm. Screening of these hits in a T. b. brucei proliferation assay highlighted three compounds with a 1H-imidazo[4,5-b]pyrazin-2(3H)-one scaffold that showed sub-micromolar activity and excellent selectivity against the MRC5 cell line. Subsequent rounds of optimisation led to the identification of compounds that exhibited good in vitro drug metabolism and pharmacokinetics (DMPK) properties, although in general this series suffered from poor solubility. A scaffold-hopping exercise led to the identification of a 1H-pyrazolo[3,4-b]pyridine scaffold, which retained potency. A number of examples were assessed in a T. b. brucei growth assay, which could differentiate static and cidal action. Compounds from the 1H-imidazo[4,5-b]pyrazin-2(3H)-one series were found to be either static or growth-slowing and not cidal. Compounds with the 1H-pyrazolo[3,4-b]pyridine scaffold were found to be cidal and showed an unusual biphasic nature in this assay, suggesting they act by at least two mechanisms.

  17. 8-THP-DHI analogs as potent Type I dual TIE-2/VEGF-R2 receptor tyrosine kinase inhibitors.

    Science.gov (United States)

    Hudkins, Robert L; Zulli, Allison L; Underiner, Ted L; Angeles, Thelma S; Aimone, Lisa D; Meyer, Sheryl L; Pauletti, Daniel; Chang, Hong; Fedorov, Elena V; Almo, Steven C; Fedorov, Alexander A; Ruggeri, Bruce A

    2010-06-01

    A novel series of 8-(2-tetrahydropyranyl)-12,13-dihydroindazolo[5,4-a]pyrrolo[3,4-c]carbazoles (THP-DHI) was synthesized and evaluated as dual TIE-2 and VEGF-R2 receptor tyrosine kinase inhibitors. Development of the structure-activity relationships (SAR) with the support of X-ray crystallography led to identification of 7f and 7g as potent, selective dual TIE-2/VEGF-R2 inhibitors with excellent cellular potency and acceptable pharmacokinetic properties. Compounds 7f and 7g were orally active in tumor models with no observed toxicity.

  18. Discovery of 7-aminofuro[2,3-c]pyridine inhibitors of TAK1: optimization of kinase selectivity and pharmacokinetics.

    Science.gov (United States)

    Hornberger, Keith R; Chen, Xin; Crew, Andrew P; Kleinberg, Andrew; Ma, Lifu; Mulvihill, Mark J; Wang, Jing; Wilde, Victoria L; Albertella, Mark; Bittner, Mark; Cooke, Andrew; Kadhim, Salam; Kahler, Jennifer; Maresca, Paul; May, Earl; Meyn, Peter; Romashko, Darlene; Tokar, Brianna; Turton, Roy

    2013-08-15

    The kinase selectivity and pharmacokinetic optimization of a series of 7-aminofuro[2,3-c]pyridine inhibitors of TAK1 is described. The intersection of insights from molecular modeling, computational prediction of metabolic sites, and in vitro metabolite identification studies resulted in a simple and unique solution to both of these problems. These efforts culminated in the discovery of compound 13a, a potent, relatively selective inhibitor of TAK1 with good pharmacokinetic properties in mice, which was active in an in vivo model of ovarian cancer.

  19. Cyclin-dependent protein kinase inhibitors including palbociclib as anticancer drugs.

    Science.gov (United States)

    Roskoski, Robert

    2016-05-01

    Cyclins and cyclin-dependent protein kinases (CDKs) are important regulatory components that are required for cell cycle progression. The levels of the cell cycle CDKs are generally constant and their activities are controlled by cyclins, proteins whose levels oscillate during each cell cycle. Additional CDK family members were subsequently discovered that play significant roles in a wide range of activities including the control of gene transcription, metabolism, and neuronal function. In response to mitogenic stimuli, cells in the G1 phase of the cell cycle produce cyclins of the D type that activate CDK4/6. These activated enzymes catalyze the monophosphorylation of the retinoblastoma protein. Then CDK2-cyclin E catalyzes the hyperphosphorylation of Rb that promotes the release and activation of the E2F transcription factors, which in turn lead to the generation of several proteins required for cell cycle progression. As a result, cells pass through the G1-restriction point and are committed to complete cell division. CDK2-cyclin A, CDK1-cyclin A, and CDK1-cyclin B are required for S, G2, and M-phase progression. Increased cyclin or CDK expression or decreased levels of endogenous CDK inhibitors such as INK4 or CIP/KIP have been observed in various cancers. In contrast to the mutational activation of EGFR, Kit, or B-Raf in the pathogenesis of malignancies, mutations in the CDKs that cause cancers are rare. Owing to their role in cell proliferation, CDKs represent natural targets for anticancer therapies. Abemaciclib (LY2835219), ribociclib (Lee011), and palbociclib (Ibrance(®) or PD0332991) target CDK4/6 with IC50 values in the low nanomolar range. Palbociclib and other CDK inhibitors bind in the cleft between the small and large lobes of the CDKs and inhibit the binding of ATP. Like ATP, palbociclib forms hydrogen bonds with residues in the hinge segment of the cleft. Like the adenine base of ATP, palbociclib interacts with catalytic spine residues CS6 and CS7

  20. Disruption of focal adhesion kinase and p53 interaction with small molecule compound R2 reactivated p53 and blocked tumor growth

    OpenAIRE

    Golubovskaya, Vita M.; Ho, Baotran; Zheng, Min; Magis, Andrew; Ostrov, David; Morrison, Carl; Cance, William G.

    2013-01-01

    Background Focal Adhesion Kinase (FAK) is a 125 kDa non-receptor kinase that plays a major role in cancer cell survival and metastasis. Methods We performed computer modeling of the p53 peptide containing the site of interaction with FAK, predicted the peptide structure and docked it into the three-dimensional structure of the N-terminal domain of FAK involved in the complex with p53. We screened small molecule compounds that targeted the site of the FAK-p53 interaction and identified compoun...

  1. Gold nanoparticles enhance the effect of tyrosine kinase inhibitors in acute myeloid leukemia therapy

    Directory of Open Access Journals (Sweden)

    Petrushev B

    2016-02-01

    Full Text Available Bobe Petrushev,1,* Sanda Boca,2,* Timea Simon,2 Cristian Berce,3 Ioana Frinc,4 Delia Dima,4 Sonia Selicean,3 Grigore-Aristide Gafencu,3 Alina Tanase,5 Mihnea Zdrenghea,4,6 Adrian Florea,7 Sorina Suarasan,2 Liana Dima,8 Raluca Stanciu,3 Ancuta Jurj,1 Anca Buzoianu,9 Andrei Cucuianu,4,6,† Simion Astilean,2,10 Alexandru Irimie,11,12 Ciprian Tomuleasa,1,4 Ioana Berindan-Neagoe1,131Research Center for Functional Genomics and Translational Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 2Nanobiophotonics and Laser Microscopy Center, Babes Bolyai University, 3Department of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 4Department of Hematology, Ion Chiricuta Oncology Institute, Cluj-Napoca, 5Department of Stem Cell Transplantation, Fundeni Clinical Institute, Bucharest, 6Department of Hematology, 7Department of Cell and Molecular Biology, 8School of Dentistry, 9Department of Pharmacology, Iuliu Hatieganu University of Medicine and Pharmacy, 10Faculty of Physics, Babes Bolyai University, 11Department of Surgery, Ion Chiricuta Oncology Institute, 12Department of Surgery, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania; 13Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA*These authors contributed equally to this work†This author passed away in February 2015Background and aims: Every year, in Europe, acute myeloid leukemia (AML is diagnosed in thousands of adults. For most subtypes of AML, the backbone of treatment was introduced nearly 40 years ago as a combination of cytosine arabinoside with an anthracycline. This therapy is still the worldwide standard of care. Two-thirds of patients achieve complete remission, although most of them ultimately relapse. Since the FLT3 mutation is the most frequent, it serves as a key molecular target for tyrosine kinase inhibitors (TKIs that inhibit FLT3 kinase. In this study, we report the

  2. Clinical efficacy of second generation tyrosine kinase inhibitor and 5-azacytidine combination in chronic myelogenous leukaemia in myeloid blast crisis.

    Science.gov (United States)

    Ghez, David; Micol, Jean-Baptiste; Pasquier, Florence; Auger, Nathalie; Saada, Véronique; Spentchian, Marc; Ianotto, Jean-Christophe; Bourhis, Jean-Henri; Bennaceur-Griscelli, Anelyse; Terré, Christine; Castaigne, Sylvie; Rigaudeau, Sophie; Rousselot, Philippe; de Botton, Stéphane

    2013-11-01

    Even in the tyrosine kinase inhibitors era, the prognosis of patients with chronic myeloid leukaemia in myeloid blast crisis remains dismal with few patients surviving longer than 6 months. Here we report the cases of 5 patients treated with the combination of 5-azacytidine and tyrosine kinase inhibitors for myeloid blast crisis CML. All patients achieved a complete haematological response including two with a complete cytogenetic and major molecular response. Two patients underwent an allogeneic stem cell transplantation. One died from relapse 34 months from diagnosis. The second is alive and free from disease at 11 months from diagnosis. The other 3 patients are still in complete haematological response after 15, 24 and 33 months of follow-up. These results suggest that the combination has a significant activity in myeloid blast crisis and may increase survival. PMID:23968731

  3. Identification of novel protein kinase CK1 delta (CK1delta) inhibitors through structure-based virtual screening.

    Science.gov (United States)

    Cozza, Giorgio; Gianoncelli, Alessandra; Montopoli, Monica; Caparrotta, Laura; Venerando, Andrea; Meggio, Flavio; Pinna, Lorenzo A; Zagotto, Giuseppe; Moro, Stefano

    2008-10-15

    In eukaryotes, protein phosphorylation of serine, threonine or tyrosine residues by protein kinases plays an important role in many cellular processes. Members of the protein kinase CK1 family usually phosphorylate residues of serine that are close to other phosphoserine in a consensus motif of pS-X-X-S, and they are implicated in the regulation of a variety of physiological processes as well as in pathologies like cancer and Alzheimer's disease. Using a structure-based virtual screening (SBVS) approach we have identified two anthraquinones as novel CK1delta inhibitors. These amino-anthraquinone analogs (derivatives 1 and 2) are among the most potent and selective CK1delta inhibitors known today (IC(50)=0.3 and 0.6 microM, respectively). PMID:18799313

  4. Targeting FAK using inhibitors of Protein-Protein Interactions

    OpenAIRE

    Philippe Rond?

    2015-01-01

    The Focal Adhesion Kinase (FAK) is involved in many aspects of the metastatic process including adhesion, migration, and invasion. Indeed, overexpression, hyperphosphorylation and/or elevated activity of FAK have been described in a variety of human cancers. Thus, the development of FAK antagonists as anti-cancer therapy, led to several small inhibitors of FAK kinase function that are currently undergoing clinical trials. FAK is a ubiquitously expressed non-receptor cytoplasmic tyrosine kinas...

  5. Expression of the Apoptosis Inhibitor Survivin and its correlation with Thymidine Kinase and Axillary Lymph Node Metastasis in Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 Introduction Many molecular factors have been demonstrated to interfere with cellular proliferation and programmed cell death.One of these factors is a recently discovered member of the “inhibitor of apoptosis protein(IAP)” called survivin. Survivin is abundantly expressed in most solid and hematologic malignancies, but undetectable in normal adult tissues. Interference with survivin function induces pleiotropic cell-division defects and apoptosis. Cytosolic thymidine kinase (TK) is a marker for prolifera...

  6. Treatment compliance and severe adverse events limit the use of tyrosine kinase inhibitors in refractory thyroid cancer

    OpenAIRE

    Chrisoulidou A; Mandanas S; Margaritidou E; Mathiopoulou L; Boudina M; Georgopoulos K; Pazaitou-Panayiotou K

    2015-01-01

    Alexandra Chrisoulidou, Stylianos Mandanas, Efterpi Margaritidou, Lemonia Mathiopoulou, Maria Boudina, Konstantinos Georgopoulos, Kalliopi Pazaitou-PanayiotouDepartment of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, GreeceObjective: The aim of the present study was to assess patient compliance with tyrosine kinase inhibitor (TKI) treatment used for refractory and progressive thyroid cancer, in addition to the efficacy and serious adverse events associated with these agents.Methods...

  7. Temporal changes in circulating P-selectin, plasminogen activator inhibitor-1, magnesium, and creatine kinase after percutaneous coronary intervention*

    OpenAIRE

    Ying, Shu-qin; Xiang, Mei-xiang; Fang, Lu; Wang, Jian-an

    2010-01-01

    Objective: This study aims to determine the mechanisms underlying restenosis and ischemia-reperfusion injury of the myocardium after percutaneous coronary intervention (PCI). Methods: The present study examined serial changes (5 min, 30 min, 2 h, 6 h, and 24 h after PCI) in circulating P-selectin, plasminogen activator inhibitor-1 (PAI-1), magnesium (Mg), and creatine kinase-myocardial band fraction (CK-MB) levels, which may be associated with restenosis and myocardial injury in patients unde...

  8. Design and synthesis of a potent inhibitor of class 1 DYRK kinases as a suppressor of adipogenesis.

    Science.gov (United States)

    Masaki, So; Kii, Isao; Sumida, Yuto; Kato-Sumida, Tomoe; Ogawa, Yasushi; Ito, Nobutoshi; Nakamura, Mitsuhiro; Sonamoto, Rie; Kataoka, Naoyuki; Hosoya, Takamitsu; Hagiwara, Masatoshi

    2015-08-01

    Dysregulation of dual-specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A) has been demonstrated in several pathological conditions, including Alzheimer's disease and cancer progression. It has been recently reported that a gain of function-mutation in the human DYRK1B gene exacerbates metabolic syndrome by enhancing obesity. In the previous study, we developed an inhibitor of DYRK family kinases (INDY) and demonstrated that INDY suppresses the pathological phenotypes induced by overexpression of DYRK1A or DYRK1B in cellular and animal models. In this study, we designed and synthesized a novel inhibitor of DYRK family kinases based on the crystal structure of the DYRK1A/INDY complex by replacing the phenol group of INDY with dibenzofuran to produce a derivative, named BINDY. This compound exhibited potent and selective inhibitory activity toward DYRK family kinases in an in vitro assay. Furthermore, treatment of 3T3-L1 pre-adipocytes with BINDY hampered adipogenesis by suppressing gene expression of the critical transcription factors PPARγ and C/EBPα. This study indicates the possibility of BINDY as a potential drug for metabolic syndrome. PMID:26145823

  9. Vascular growth responses to chronic arterial occlusion are unaffected by myeloid specific focal adhesion kinase (FAK) deletion.

    Science.gov (United States)

    Heuslein, Joshua L; Murrell, Kelsey P; Leiphart, Ryan J; Llewellyn, Ryan A; Meisner, Joshua K; Price, Richard J

    2016-01-01

    Arteriogenesis, or the lumenal expansion of pre-existing arterioles in the presence of an upstream occlusion, is a fundamental vascular growth response. Though alterations in shear stress stimulate arteriogenesis, the migration of monocytes into the perivascular space surrounding collateral arteries and their differentiation into macrophages is critical for this vascular growth response to occur. Focal adhesion kinase's (FAK) role in regulating cell migration has recently been expanded to primary macrophages. We therefore investigated the effect of the myeloid-specific conditional deletion of FAK on vascular remodeling in the mouse femoral arterial ligation (FAL) model. Using laser Doppler perfusion imaging, whole mount imaging of vascular casted gracilis muscles, and immunostaining for CD31 in gastrocnemius muscles cross-sections, we found that there were no statistical differences in perfusion recovery, arteriogenesis, or angiogenesis 28 days after FAL. We therefore sought to determine FAK expression in different myeloid cell populations. We found that FAK is expressed at equally low levels in Ly6C(hi) and Ly6C(lo) blood monocytes, however expression is increased over 2-fold in bone marrow derived macrophages. Ultimately, these results suggest that FAK is not required for monocyte migration to the perivascular space and that vascular remodeling following arterial occlusion occurs independently of myeloid specific FAK. PMID:27244251

  10. Multiple myeloma is affected by multiple and heterogeneous somatic mutations in adhesion- and receptor tyrosine kinase signaling molecules

    International Nuclear Information System (INIS)

    Multiple myeloma (MM) is a largely incurable plasma cell malignancy with a poorly understood and heterogeneous clinical course. To identify potential, functionally relevant somatic mutations in MM, we performed whole-exome sequencing of five primary MM, corresponding germline DNA and six MM cell lines, and developed a bioinformatics strategy that also integrated published mutational data of 38 MM patients. Our analysis confirms that identical, recurrent mutations of single genes are infrequent in MM, but highlights that mutations cluster in important cellular pathways. Specifically, we show enrichment of mutations in adhesion molecules of MM cells, emphasizing the important role for the interaction of the MM cells with their microenvironment. We describe an increased rate of mutations in receptor tyrosine kinases (RTKs) and associated signaling effectors, for example, in EGFR, ERBB3, KRAS and MAP2K2, pointing to a role of aberrant RTK signaling in the development or progression of MM. The diversity of mutations affecting different nodes of a particular signaling network appears to be an intrinsic feature of individual MM samples, and the elucidation of intra- as well as interindividual redundancy in mutations that affect survival pathways will help to better tailor targeted therapeutic strategies to the specific needs of the MM patient

  11. Down-regulation of integrin β1 and focal adhesion kinase in renal glomeruli under various hemodynamic conditions.

    Directory of Open Access Journals (Sweden)

    Xiaoli Yuan

    Full Text Available Given that integrin β1 is an important component of the connection to maintain glomerular structural integrity, by binding with multiple extracellular matrix proteins and mediating intracellular signaling. Focal adhesion kinase (FAK is the most essential intracellular integrator in the integrin β1-FAK signalling pathway. Here, we investigated the changes of the two molecules and visualized the possible interaction between them under various hemodynamic conditions in podocytes. Mice kidney tissues were prepared using in vivo cryotechnique (IVCT and then were stained and observed using light microscopy, confocal laser scanning microscopy and immunoelectron microscopy. The expression of these molecules were examined by western blot. Under the normal condition, integrin β1 stained continually and evenly at the membrane, and FAK was located in the cytoplasm and nuclei of the podocytes. There were significant colocalized plaques of two molecules. But under acute hypertensive and cardiac arrest conditions, integrin β1 decreased and stained intermittently. Similarly, FAK decreased and appeared uneven. Additionally, FAK translocated to the nuclei of the podocytes. As a result, the colocalization of integrin β1 and FAK reduced obviously under these conditions. Western blot assay showed a consistent result with the immunostaining. Collectively, the abnormal redistribution and decreased expressions of integrin β1 and FAK are important molecular events in regulating the functions of podocytes under abnormal hemodynamic conditions. IVCT could offer considerable advantages for morphological analysis when researching renal diseases.

  12. Advances in tetrahydropyrido[1,2-a]isoindolone (valmerins) series: Potent glycogen synthase kinase 3 and cyclin dependent kinase 5 inhibitors.

    Science.gov (United States)

    Boulahjar, Rajâa; Ouach, Aziz; Bourg, Stéphane; Bonnet, Pascal; Lozach, Olivier; Meijer, Laurent; Guguen-Guillouzo, Christiane; Le Guevel, Rémy; Lazar, Saïd; Akssira, Mohamed; Troin, Yves; Guillaumet, Gérald; Routier, Sylvain

    2015-08-28

    An efficient synthetic strategy was developed to modulate the structure of the tetrahydropyridine isoindolone (Valmerin) skeleton. A library of more than 30 novel final structures was generated. Biological activities on CDK5 and GSK3 as well as cellular effects on cancer cell lines were measured for each novel compound. Additionally docking studies were performed to support medicinal chemistry efforts. A strong GSK3/CDK5 dual inhibitor (38, IC50 GSK3/CDK5 32/84 nM) was obtained. A set of highly selective GSK3 inhibitors was synthesized by fine-tuning structural modifications (29 IC50 GSK3/CDK5 32/320 nM). Antiproliferative effects on cells were correlated with the in vitro kinase activities and the best effects were obtained with lung and colon cell lines. PMID:26142492

  13. Interruption of the blood-stage cycle of the malaria parasite, Plasmodium chabaudi, by protein tyrosine kinase inhibitors

    Directory of Open Access Journals (Sweden)

    M.L. Gazarini

    2003-11-01

    Full Text Available Malaria is a devastating disease caused by a unicellular protozoan, Plasmodium, which affects 3.7 million people every year. Resistance of the parasite to classical treatments such as chloroquine requires the development of new drugs. To gain insight into the mechanisms that control Plasmodium cell cycle, we have examined the effects of kinase inhibitors on the blood-stage cycle of the rodent malaria parasite, Plasmodium chabaudi. In vitro incubation of red blood cells for 17 h at 37ºC with the inhibitors led to a decrease in the percent of infected cells, compared to control treatment, as follows: genistein (200 µM - 75%, staurosporine (1 µM - 58%, R03 (1 µM - 75%, and tyrphostins B44 (100 µM - 66% and B46 (100 µM - 68%. All these treatments were shown to retard or prevent maturation of the intraerythrocytic parasites. The diverse concentration ranges at which these inhibitors exert their effects give a clue as to the types of signals that initiate the transitions between the different developmental stages of the parasite. The present data support our hypothesis that the maturation of the intraerythrocytic cycle of malaria parasites requires phosphorylation. In this respect, we have recently reported a high Ca2+ microenvironment surrounding the parasite within red blood cells. Several kinase activities are modulated by Ca2+. The molecular identification of the targets of these kinases could provide new strategies against malaria.

  14. Soluble fms-like tyrosine kinase-1 and endothelial adhesion molecules (intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1) as predictive markers for blood pressure reduction after renal sympathetic denervation.

    Science.gov (United States)

    Dörr, Oliver; Liebetrau, Christoph; Möllmann, Helge; Gaede, Luise; Troidl, Christian; Rixe, Johannes; Hamm, Christian; Nef, Holger

    2014-05-01

    Renal sympathetic denervation (RSD) is a treatment option for patients with resistant arterial hypertension, but in some patients it is not successful. Predictive parameters on the success of RSD remain unknown. The angiogenic factors soluble fms-like tyrosine kinase-1 (sFLT-1), intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) are known to be associated with endothelial dysfunction, vascular remodeling, and hypertension. We evaluated whether sFLT-1, ICAM-1, and VCAM-1 are predictive markers for blood pressure reduction after RSD. Consecutive patients (n=55) undergoing renal denervation were included. Venous serum samples for measurement of sFlt-1, ICAM-1, and VCAM-1 were collected before and 6 months after RSD. A therapeutic response was defined as an office systolic blood pressure reduction of >10 mm Hg 6 months after RSD. A significant mean office systolic blood pressure reduction of 31.2 mm Hg was observed in 46 patients 6 months after RSD. Nine patients were classified as nonresponders, with a mean systolic blood pressure reduction of 4.6 mm Hg. At baseline, sFLT-1 levels were significantly higher in responders than in nonresponders (P<0.001) as were ICAM-1 (P<0.001) and VCAM-1 levels (P<0.01). The areas under the curve for sFLT-1, ICAM-1, and VCAM-1 were 0.82 (interquartile range, 0.718-0.921; P<0.001), 0.754 (0.654-0.854; P<0.001), and 0.684 (0.564-804; P=0.01), respectively, demonstrating prediction of an RSD response. Responders showed significantly higher serum levels of sFLT-1, ICAM-1, and VCAM-1 at baseline compared with nonresponders. Thus, this study identified for the first time potential biomarkers with a predictive value indicating a responder or nonresponder before renal denervation. PMID:24470464

  15. Reduced intensity conditioning is superior to nonmyeloablative conditioning for older chronic myelogenous leukemia patients undergoing hematopoietic cell transplant during the tyrosine kinase inhibitor era

    DEFF Research Database (Denmark)

    Warlick, Erica; Ahn, Kwang Woo; Pedersen, Tanya L;

    2012-01-01

    Tyrosine kinase inhibitors (TKIs) and reduced intensity conditioning (RIC)/nonmyeloablative (NMA) conditioning hematopoietic cell transplants (HCTs) have changed the therapeutic strategy for chronic myelogenous leukemia (CML) patients. We analyzed post-HCT outcomes of 306 CML patients reported to...

  16. 5-Substituted 3-isopropyl-7-[4-(2-pyridyl)benzyl]amino-1(2)H-pyrazolo[4,3-d]pyrimidines with anti-proliferative activity as potent and selective inhibitors of cyclin-dependent kinases.

    Science.gov (United States)

    Vymětalová, Ladislava; Havlíček, Libor; Šturc, Antonín; Skrášková, Zuzana; Jorda, Radek; Pospíšil, Tomáš; Strnad, Miroslav; Kryštof, Vladimír

    2016-03-01

    A series of 5-substituted 3-isopropyl-7-[4-(2-pyridyl)benzyl]amino-1(2)H-pyrazolo[4,3-d]pyrimidine derivatives was synthesized and evaluated for their cyclin-dependent kinase (CDK) inhibition activity. The most potent compounds contained various hydroxyalkylamines at the 5 position and possessed low nanomolar IC50 values for CDK2 and CDK5. Preliminary profiling of one of the most active compounds on a panel of 50 protein kinases revealed its high selectivity for CDKs. The compounds arrested cells in S and G2/M phases, and induced apoptosis in various cancer cell lines. Significant dephosphorylation of the C-terminus of RNA polymerase II and focal adhesion kinase (FAK), well-established substrates of CDKs, has been found in treated cells. Cleavage of PARP-1, down-regulation of Mcl-1 and activation of caspases correlated well with CDK inhibition and confirmed apoptosis as the primary type of cell death induced in cancer cells treated with the compounds in vitro. A comparison of known purine-based CDK inhibitor CR8 with its pyrazolo[4,3-d]pyrimidine bioisosteres confirmed that the novel compounds are more potent in cellular assays than purines. Therefore, pyrazolo[4,3-d]pyrimidine may emerge as a novel scaffold in medicinal chemistry and as a source of potent CDK inhibitors. PMID:26851505

  17. The Bruton tyrosine kinase inhibitor PCI-32765 thwarts chronic lymphocytic leukemia cell survival and tissue homing in vitro and in vivo

    OpenAIRE

    Ponader, Sabine; Chen, Shih-Shih; Buggy, Joseph J.; Balakrishnan, Kumudha; Gandhi, Varsha; William G Wierda; Michael J Keating; O'Brien, Susan; Chiorazzi, Nicholas; Burger, Jan A.

    2012-01-01

    B-cell receptor (BCR) signaling is a critical pathway in the pathogenesis of several B-cell malignancies, including chronic lymphocytic leukemia (CLL), and can be targeted by inhibitors of BCR-associated kinases, such as Bruton tyrosine kinase (Btk). PCI-32765, a selective, irreversible Btk inhibitor, is a novel, molecularly targeted agent for patients with B-cell malignancies, and is particularly active in patients with CLL. In this study, we analyzed the mechanism of action of PCI-32765 in ...

  18. IkB kinase-beta inhibitor attenuates hepatic fibrosis in mice

    Institute of Scientific and Technical Information of China (English)

    Jue Wei; Min Shi; Wei Qi Wu; Ting Wang; Na Wang; Jia-Li Ma; Yu-Gang Wang

    2011-01-01

    AIM: To investigate the anti-fibrosis effect of IκkB kinase-beta inhibitor (IKK2 inhibitor IMD0354) in liver fibrosis. METHODS: Twenty male C57BL6 mice were divided into four groups. Five high-fat fed mice were injected with lipopolysaccharide (LPS, 10 mg/kg) intraperitoneally and five high-fat fed mice were without LPS injection to build models of liver injury, and the intervention group (five mice) was injected intraperitoneally with IKK2 inhibitor (IMD 30 mg/kg for 14 d), while the remaining five mice received a normal diet as controls. Hepatic function, pathological evaluation and liver interleukin- 6 (IL-6) expression were examined. Western blotting and real-time polymerase chain reaction were used to detect the expressions of nuclear factor-κkB (NF-κkB), alpha-smooth muscle actin (α-SMA), tumor growth factor-beta1 (TGF-β1), tumor necrosis factor-alpha (TNF-α), typeⅠand type Ⅲ collagen proteins and mRNA. RESULTS: A mouse model of liver injury was successfully established, and IMD decreased nuclear translocation translocation of NF-κkB p65 in liver cells. In the IMD-treated group, the levels of alanine aminotransferase (103 ± 9.77 μ/L vs 62.4 ± 7.90 μ/L, P < 0.05) and aminotransferase (295.8 ± 38.56 μ/L vs 212 ± 25.10 μ/L, P < 0.05) were significantly decreased when compared with the model groups. The histological changes were significantly ameliorated. After treatment, the expressions of IL-6 (681 ± 45.96 vs 77 ± 7.79, P < 0.05), TGF-β1 (Western blotting 5.65% ± 0.017% vs 2.73% ± 0.005%, P < 0.05), TNF-α (11.58% ± 0.0063% vs 8.86% ± 0.0050%, P < 0.05), typeⅠcollagen (4.49% ± 0.014% vs 1.90% ± 0.0006%, P < 0.05) and type Ⅲ collagen (3.46% ± 0.008% vs 2.29% ± 0.0035%, P < 0.05) as well as α-SMA (6.19 ± 0.0036 μ/L vs 2.16 ± 0.0023 μ/L, P < 0.05) protein and mRNA were downregulated in the IMD group compared to the fibrosis control groups (P < 0.05).CONCLUSION: IKK2 inhibitor IMD markedly improved non-alcoholic fatty liver

  19. High throughput screens yield small molecule inhibitors of Leishmania CRK3:CYC6 cyclin-dependent kinase.

    Directory of Open Access Journals (Sweden)

    Roderick G Walker

    Full Text Available BACKGROUND: Leishmania species are parasitic protozoa that have a tightly controlled cell cycle, regulated by cyclin-dependent kinases (CDKs. Cdc2-related kinase 3 (CRK3, an essential CDK in Leishmania and functional orthologue of human CDK1, can form an active protein kinase complex with Leishmania cyclins CYCA and CYC6. Here we describe the identification and synthesis of specific small molecule inhibitors of bacterially expressed Leishmania CRK3:CYC6 using a high throughput screening assay and iterative chemistry. We also describe the biological activity of the molecules against Leishmania parasites. METHODOLOGY/PRINCIPAL FINDINGS: In order to obtain an active Leishmania CRK3:CYC6 protein kinase complex, we developed a co-expression and co-purification system for Leishmania CRK3 and CYC6 proteins. This active enzyme was used in a high throughput screening (HTS platform, utilising an IMAP fluorescence polarisation assay. We carried out two chemical library screens and identified specific inhibitors of CRK3:CYC6 that were inactive against the human cyclin-dependent kinase CDK2:CycA. Subsequently, the best inhibitors were tested against 11 other mammalian protein kinases. Twelve of the most potent hits had an azapurine core with structure activity relationship (SAR analysis identifying the functional groups on the 2 and 9 positions as essential for CRK3:CYC6 inhibition and specificity against CDK2:CycA. Iterative chemistry allowed synthesis of a number of azapurine derivatives with one, compound 17, demonstrating anti-parasitic activity against both promastigote and amastigote forms of L. major. Following the second HTS, 11 compounds with a thiazole core (active towards CRK3:CYC6 and inactive against CDK2:CycA were tested. Ten of these hits demonstrated anti-parasitic activity against promastigote L. major. CONCLUSIONS/SIGNIFICANCE: The pharmacophores identified from the high throughput screens, and the derivatives synthesised, selectively

  20. A phase II study of enzastaurin, a protein kinase C beta inhibitor, in patients with relapsed or refractory mantle cell lymphoma

    NARCIS (Netherlands)

    F. Morschhauser; J.F. Seymour; H.C. Kluin-Nelemans (Hanneke); A. Grigg; M. Wolf; M. Pfreundschuh (Michael); H. Tilly (Herve); J. Raemaekers; M.B. van 't Veer (Mars); N. Milpied; G. Cartron; A. Pezzutto; A. Spencer; F. Reyes; M. Dreyling (Martin)

    2008-01-01

    textabstractBackground: Protein kinase C beta (PKCβ), a pivotal enzyme in B-cell signaling and survival, is overexpressed in most cases of mantle cell lymphoma (MCL). Activation of PI3K/AKT pathway is involved in pathogenesis of MCL. Enzastaurin, an oral serine/threonine kinase inhibitor, suppresses

  1. A phase II study of enzastaurin, a protein kinase C beta inhibitor, in patients with relapsed or refractory mantle cell lymphoma

    NARCIS (Netherlands)

    Morschhauser, F.; Seymour, J. F.; Kluin-Nelemans, H. C.; Grigg, A.; Wolf, M.; Pfreundschuh, M.; Tilly, H.; Raemaekers, J.; van 't Veer, M. B.; Milpied, N.; Cartron, G.; Pezzutto, A.; Spencer, A.; Reyes, F.; Dreyling, M.

    2008-01-01

    Background: Protein kinase C beta (PKC beta), a pivotal enzyme in B-cell signaling and survival, is overexpressed in most cases of mantle cell lymphoma (MCL). Activation of PI3K/AKT pathway is involved in pathogenesis of MCL. Enzastaurin, an oral serine/threonine kinase inhibitor, suppresses signali

  2. Growth-Factor-Driven Rescue to Receptor Tyrosine Kinase (RTK) Inhibitors through Akt and Erk Phosphorylation in Pediatric Low Grade Astrocytoma and Ependymoma

    NARCIS (Netherlands)

    Sie, Mariska; den Dunnen, Wilfred F. A.; Lourens, Harm Jan; Meeuwsen-de Boer, Tiny G. J.; Scherpen, Frank J. G.; Zomerman, Walderik W.; Kampen, Kim R.; Hoving, Eelco W.; de Bont, Eveline S. J. M.

    2015-01-01

    Up to now, several clinical studies have been started investigating the relevance of receptor tyrosine kinase (RTK) inhibitors upon progression free survival in various pediatric brain tumors. However, single targeted kinase inhibition failed, possibly due to tumor resistance mechanisms. The present

  3. Role of focal adhesion tyrosine kinases in GPVI-dependent platelet activation and reactive oxygen species formation.

    Directory of Open Access Journals (Sweden)

    Naadiya Carrim

    Full Text Available We have previously shown the presence of a TRAF4/p47phox/Hic5/Pyk2 complex associated with the platelet collagen receptor, GPVI, consistent with a potential role of this complex in GPVI-dependent ROS formation. In other cell systems, NOX-dependent ROS formation is facilitated by Pyk2, which along with its closely related homologue FAK are known to be activated and phosphorylated downstream of ligand binding to GPVI.To evaluate the relative roles of Pyk2 and FAK in GPVI-dependent ROS formation and to determine their location within the GPVI signaling pathway.Human and mouse washed platelets (from WT or Pyk2 KO mice were pre-treated with pharmacological inhibitors targeting FAK or Pyk2 (PF-228 and Tyrphostin A9, respectively and stimulated with the GPVI-specific agonist, CRP. FAK, but not Pyk2, was found to be essential for GPVI-dependent ROS production and aggregation. Subsequent human platelet studies with PF-228 confirmed FAK is essential for GPVI-mediated phosphatidylserine exposure, α-granule secretion (P-selectin (CD62P surface expression and integrin αIIbβ3 activation. To determine the precise location of FAK within the GPVI pathway, we analyzed the effect of PF-228 inhibition in CRP-stimulated platelets in conjunction with immunoprecipitation and pulldown analysis to show that FAK is downstream of Lyn, Spleen tyrosine kinase (Syk, PI3-K and Bruton's tyrosine kinase (Btk and upstream of Rac1, PLCγ2, Ca2+ release, PKC, Hic-5, NOX1 and αIIbβ3 activation.Overall, these data suggest a novel role for FAK in GPVI-dependent ROS formation and platelet activation and elucidate a proximal signaling role for FAK within the GPVI pathway.

  4. Target prices for mass production of tyrosine kinase inhibitors for global cancer treatment

    Science.gov (United States)

    Hill, Andrew; Gotham, Dzintars; Fortunak, Joseph; Meldrum, Jonathan; Erbacher, Isabelle; Martin, Manuel; Shoman, Haitham; Levi, Jacob; Powderly, William G; Bower, Mark

    2016-01-01

    Objective To calculate sustainable generic prices for 4 tyrosine kinase inhibitors (TKIs). Background TKIs have proven survival benefits in the treatment of several cancers, including chronic myeloid leukaemia, breast, liver, renal and lung cancer. However, current high prices are a barrier to treatment. Mass production of low-cost generic antiretrovirals has led to over 13 million people being on HIV/AIDS treatment worldwide. This analysis estimates target prices for generic TKIs, assuming similar methods of mass production. Methods Four TKIs with patent expiry dates in the next 5 years were selected for analysis: imatinib, erlotinib, lapatinib and sorafenib. Chemistry, dosing, published data on per-kilogram pricing for commercial transactions of active pharmaceutical ingredient (API), and quotes from manufacturers were used to estimate costs of production. Analysis included costs of excipients, formulation, packaging, shipping and a 50% profit margin. Target prices were compared with current prices. Global numbers of patients eligible for treatment with each TKI were estimated. Results API costs per kg were $347–$746 for imatinib, $2470 for erlotinib, $4671 for lapatinib, and $3000 for sorafenib. Basing on annual dose requirements, costs of formulation/packaging and a 50% profit margin, target generic prices per person-year were $128–$216 for imatinib, $240 for erlotinib, $1450 for sorafenib, and $4020 for lapatinib. Over 1 million people would be newly eligible to start treatment with these TKIs annually. Conclusions Mass generic production of several TKIs could achieve treatment prices in the range of $128–$4020 per person-year, versus current US prices of $75161–$139 138. Generic TKIs could allow significant savings and scaling-up of treatment globally, for over 1 million eligible patients. PMID:26817636

  5. Tyrosine kinase inhibitor NVP-BGJ398 functionally improves FGFR3-related dwarfism in mouse model.

    Science.gov (United States)

    Komla-Ebri, Davide; Dambroise, Emilie; Kramer, Ina; Benoist-Lasselin, Catherine; Kaci, Nabil; Le Gall, Cindy; Martin, Ludovic; Busca, Patricia; Barbault, Florent; Graus-Porta, Diana; Munnich, Arnold; Kneissel, Michaela; Di Rocco, Federico; Biosse-Duplan, Martin; Legeai-Mallet, Laurence

    2016-05-01

    Achondroplasia (ACH) is the most frequent form of dwarfism and is caused by gain-of-function mutations in the fibroblast growth factor receptor 3-encoding (FGFR3-encoding) gene. Although potential therapeutic strategies for ACH, which aim to reduce excessive FGFR3 activation, have emerged over many years, the use of tyrosine kinase inhibitor (TKI) to counteract FGFR3 hyperactivity has yet to be evaluated. Here, we have reported that the pan-FGFR TKI, NVP-BGJ398, reduces FGFR3 phosphorylation and corrects the abnormal femoral growth plate and calvaria in organ cultures from embryos of the Fgfr3Y367C/+ mouse model of ACH. Moreover, we demonstrated that a low dose of NVP-BGJ398, injected subcutaneously, was able to penetrate into the growth plate of Fgfr3Y367C/+ mice and modify its organization. Improvements to the axial and appendicular skeletons were noticeable after 10 days of treatment and were more extensive after 15 days of treatment that started from postnatal day 1. Low-dose NVP-BGJ398 treatment reduced intervertebral disc defects of lumbar vertebrae, loss of synchondroses, and foramen-magnum shape anomalies. NVP-BGJ398 inhibited FGFR3 downstream signaling pathways, including MAPK, SOX9, STAT1, and PLCγ, in the growth plates of Fgfr3Y367C/+ mice and in cultured chondrocyte models of ACH. Together, our data demonstrate that NVP-BGJ398 corrects pathological hallmarks of ACH and support TKIs as a potential therapeutic approach for ACH. PMID:27064282

  6. Effects of inhibitor of κB kinase activity in the nucleus accumbens on emotional behavior.

    Science.gov (United States)

    Christoffel, Daniel J; Golden, Sam A; Heshmati, Mitra; Graham, Ami; Birnbaum, Shari; Neve, Rachael L; Hodes, Georgia E; Russo, Scott J

    2012-11-01

    Inhibitor of κB kinase (IκK) has historically been studied in the context of immune response and inflammation, but recent evidence demonstrates that IκK activity is necessary and sufficient for regulation of neuronal function. Chronic social defeat stress of mice increases IκK activity in the nucleus accumbens (NAc) and this increase is strongly correlated to depression-like behaviors. Inhibition of IκK signaling results in a reversal of chronic social defeat stress-induced social avoidance behavior. Here, we more completely define the role of IκK in anxiety and depressive-like behaviors. Mice underwent stereotaxic microinjection of a herpes simplex virus expressing either green fluorescent protein, a constitutively active form of IκK (IκKca), or a dominant negative form of IκK into the NAc. Of all three experimental groups, only mice expressing IκKca show a behavioral phenotype. Expression of IκKca results in a decrease in the time spent in the non-periphery zones of an open field arena and increased time spent immobile during a forced swim test. No baseline differences in sucrose preference were observed, but following the acute swim stress we noted a marked reduction in sucrose preference. To determine whether IκK activity alters responses to other acute stressors, we examined behavior and spine morphology in mice undergoing an acute social defeat stress. We found that IκKca enhanced social avoidance behavior and promoted thin spine formation. These data show that IκK in NAc is a critical regulator of both depressive- and anxiety-like states and may do so by promoting the formation of immature excitatory synapses.

  7. Specific activin receptor-like kinase 3 inhibitors enhance liver regeneration.

    Science.gov (United States)

    Tsugawa, Daisuke; Oya, Yuki; Masuzaki, Ryota; Ray, Kevin; Engers, Darren W; Dib, Martin; Do, Nhue; Kuramitsu, Kaori; Ho, Karen; Frist, Audrey; Yu, Paul B; Bloch, Kenneth D; Lindsley, Craig W; Hopkins, Corey R; Hong, Charles C; Karp, Seth J

    2014-12-01

    Pharmacologic agents to enhance liver regeneration after injury would have wide therapeutic application. Based on previous work suggesting inhibition of bone morphogenetic protein (BMP) signaling stimulates liver regeneration, we tested known and novel BMP inhibitors for their ability to accelerate regeneration in a partial hepatectomy (PH) model. Compounds were produced based on the 3,6-disubstituted pyrazolo[1,5-a] pyrimidine core of the BMP antagonist dorsomorphin and evaluated for their ability to inhibit BMP signaling and enhance liver regeneration. Antagonists of the BMP receptor activin receptor-like kinase 3 (ALK3), including LDN-193189 (LDN; 4-[6-[4-(1-piperazinyl)phenyl]pyrazolo[1,5-a]pyrimidin-3-yl]-quinoline), DMH2 (4-(2-(4-(3-(quinolin-4-yl)pyrazolo[1,5-a]pyrimidin-6-yl)phenoxy)ethyl)morpholine; VU0364849), and the novel compound VU0465350 (7-(4-isopropoxyphenyl)-3-(1H-pyrazol-4-yl)imidazo[1,2-a]pyridine; VU5350), blocked SMAD phosphorylation in vitro and in vivo, and enhanced liver regeneration after PH. In contrast, an antagonist of the BMP receptor ALK2, VU0469381 (5-(6-(4-methoxyphenyl)pyrazolo[1,5-a]pyrimidin-3-yl)quinolone; 1LWY), did not affect liver regeneration. LDN did not affect liver synthetic or metabolic function. Mechanistically, LDN increased serum interleukin-6 levels and signal transducer and activator of transcription 3 phosphorylation in the liver, and modulated other factors known to be important for liver regeneration, including suppressor of cytokine signaling 3 and p53. These findings suggest that inhibition of ALK3 may be part of a therapeutic strategy for treating human liver disease. PMID:25271257

  8. Efficient activation of reconstructed rat embryos by cyclin-dependent kinase inhibitors.

    Directory of Open Access Journals (Sweden)

    Robin L Webb

    Full Text Available BACKGROUND: Over the last decade a number of species, from farm animals to rodents, have been cloned using somatic cell nuclear transfer technology (SCNT. This technique has the potential to revolutionize the way that genetically modified animals are made. In its current state, the process of SCNT is very inefficient (<5% success rate, with several technical and biological hurdles hindering development. Yet, SCNT provides investigators with powerful advantages over other approaches, such as allowing for prescreening for the desired level of transgene expression and eliminating the excess production of undesirable wild-type animals. The rat plays a significant role in biomedical research, but SCNT has been problematic for this species. In this study, we address one aspect of the problem by evaluating methods of activation in artificially constructed rat embryos. PRINCIPAL FINDINGS: We demonstrate that treatment with a calcium ionophore (ionomycin combined with a variety of cyclin-dependent kinase inhibitors is an effective way to activate rat embryos. This is in contrast to methods developed for the mouse embryo, which tolerates much less specific chemical treatments. Methods developed to activate mouse embryos do not translate well to rat embryos. CONCLUSIONS: Activation methods developed for one species will not necessarily translate to another species, even if it is closely related. Further, the parthenogenic response to chemical activators is not always a reliable indicator of how reconstructed embryos will react to the same activation method. A better understanding of rat oocyte physiology, although essential for developing better models of disease, may also provide insights that will be useful for making the SCNT process more efficient.

  9. Research progress of protein kinase B/Akt inhibitors%蛋白激酶B/Akt抑制剂

    Institute of Scientific and Technical Information of China (English)

    郝茜; 钟嫄; 王朋; 赵桂森

    2011-01-01

    PI3K (phosphatidylinositol 3-kinase)/Akt (protein kinase B, PKB) signaling pathway plays a key role in cell growth and survival. Excessive activation of PI3K/Akt pathway has been found in many tumors. In more than 50% of human tumors, Akt or/and its upstream regulatory molecules (such as PTEN and PI3K) changes abnormally. So Akt has become a hot target for cancer prevention and therapy. Recently, many effective small-molecule Akt inhibitors with different mechanisms have been found. According to the binding site and/or the chemical structures of various Akt inhibitors, they are divided into ATP competitive inhibitor, Akt allosteric inhibitor and phosphatidylinositol analog inhibitor. This paper reviews the relationship between PI3K/Akt pathway and tumors, and the research progress of Akt inhibitor, which will contribute to the design of new anti-tumor drugs.%磷脂酰肌醇-3-激酶(phosphatidylinositol 3-kinase,PI3K)/蛋白激酶B(protein kinase B,PKB/Akt)信号通路在细胞生长与存活中起着关键作用,PI3K/Akt通路的过度激活在多种肿瘤中常见.Akt激酶本身以及Akt激酶上游调节分子,例如PTEN和PI3K,在超过50%的人类肿瘤中均有异常变化.因此Akt成为肿瘤预防和肿瘤靶向治疗的热点之一.许多小分子化合物通过不同机制抑制Akt活性,根据小分子抑制剂与激酶的结合部位和化学结构不同,主要分为ATP竞争性抑制剂、Akt变构抑制剂和磷脂酰肌醇类似物抑制剂.本文综述了PI3K/Akt通路与肿瘤的关系和Akt抑制剂的研究现状,为新型抗癌药物的设计研究提供参考.

  10. Treatment of human pre-B acute lymphoblastic leukemia with the Aurora kinase inhibitor PHA-739358 (Danusertib

    Directory of Open Access Journals (Sweden)

    Fei Fei

    2012-06-01

    Full Text Available Abstract Background Treatment of Philadelphia chromosome-positive acute lymphoblastic leukemias (Ph-positive ALL with clinically approved inhibitors of the Bcr/Abl tyrosine kinase frequently results in the emergence of a leukemic clone carrying the T315I mutation in Bcr/Abl, which confers resistance to these drugs. PHA-739358, an Aurora kinase inhibitor, was reported to inhibit the Bcr/Abl T315I mutant in CML cells but no preclinical studies have examined this in detail in human ALL. Results We compared the sensitivity of human Bcr/Abl T315I, Bcr/Abl wild type and non-Bcr/Abl ALL cells to this drug. PHA-739358 inhibited proliferation and induced apoptosis independently of Bcr/Abl, the T315I mutation, or presence of the tumor suppressor p53, but the degree of effectiveness varied between different ALL samples. Since short-term treatment with a single dose of drug only transiently inhibited proliferation, we tested combination treatments of PHA-739358 with the farnesyltransferase inhibitor Lonafarnib, with vincristine and with dasatinib. All combinations reduced viability and cell numbers compared to treatment with a single drug. Clonogenic assays showed that 25 nM PHA-739358 significantly reduced the colony growth potential of Ph-positive ALL cells, and combined treatment with a second drug abrogated colony growth in this assay. PHA-739358 further effectively blocked Bcr/Abl tyrosine kinase activity and Aurora kinase B in vivo, and mice transplanted with human Bcr/Abl T315I ALL cells treated with a 3x 7-day cycle of PHA-739358 as mono-treatment had significantly longer survival. Conclusions PHA-739358 represents an alternative drug for the treatment of both Ph-positive and negative ALL, although combined treatment with a second drug may be needed to eradicate the leukemic cells.

  11. 3-Amido pyrrolopyrazine JAK kinase inhibitors: development of a JAK3 vs JAK1 selective inhibitor and evaluation in cellular and in vivo models.

    Science.gov (United States)

    Soth, Michael; Hermann, Johannes C; Yee, Calvin; Alam, Muzaffar; Barnett, Jim W; Berry, Pamela; Browner, Michelle F; Frank, Karl; Frauchiger, Sandra; Harris, Seth; He, Yang; Hekmat-Nejad, Mohammad; Hendricks, Than; Henningsen, Robert; Hilgenkamp, Ramona; Ho, Hoangdung; Hoffman, Ann; Hsu, Pei-Yuan; Hu, Dong-Qing; Itano, Andrea; Jaime-Figueroa, Saul; Jahangir, Alam; Jin, Sue; Kuglstatter, Andreas; Kutach, Alan K; Liao, Cheng; Lynch, Stephen; Menke, John; Niu, Linghao; Patel, Vaishali; Railkar, Aruna; Roy, Douglas; Shao, Ada; Shaw, David; Steiner, Sandra; Sun, Yongliang; Tan, Seng-Lai; Wang, Sandra; Vu, Minh Diem

    2013-01-10

    The Janus kinases (JAKs) are involved in multiple signaling networks relevant to inflammatory diseases, and inhibition of one or more members of this class may modulate disease activity or progression. We optimized a new inhibitor scaffold, 3-amido-5-cyclopropylpyrrolopyrazines, to a potent example with reasonable kinome selectivity, including selectivity for JAK3 versus JAK1, and good biopharmaceutical properties. Evaluation of this analogue in cellular and in vivo models confirmed functional selectivity for modulation of a JAK3/JAK1-dependent IL-2 stimulated pathway over a JAK1/JAK2/Tyk2-dependent IL-6 stimulated pathway.

  12. Pervanadate-induced adhesion of CD4+ T cell to fibronectin is associated with tyrosine phosphorylation of paxillin.

    Science.gov (United States)

    Miron, S; Kachalsky, S G; Hershkoviz, R; Lider, O

    1997-09-01

    The initial stages of T cell activation involve tyrosine protein kinase-mediated intracellular signaling events. Integrin-mediated adhesion of CD4+ T lymphocytes to extracellular matrix glycoproteins, such as fibronectin, is an activation-dependent process. The involvement of tyrosine protein kinases in the adhesion of CD4+ T cells to fibronectin was examined using pervanadate, a protein-tyrosine phosphatase inhibitor. Pervanadate induced the adhesion of human CD4+ T cells to immobilized fibronectin in a beta1 integrin-mediated fashion, and adhesion was associated with an increase of protein tyrosine phosphorylation. Tyrosine protein kinase inhibitors abrogated both T cell adhesion and intracellular protein tyrosine phosphorylation. Participation of cytoskeletal proteins in the pervanadate-induced T cell adhesion was indicated because cytoskeleton disruption by cytochalasin B inhibited cell adhesion to fibronectin. We demonstrate that the cytoskeletal protein paxillin underwent time-dependent tyrosine phosphorylation simultaneously with pervanadate-induced T cell adhesion to fibronectin. Tyrosine phosphorylation of paxillin was related to cell adhesion, since pretreatment of T cells with cytochalasin B abrogated both adhesion and phosphorylation. This study demonstrates a correlation between activation of protein tyrosine kinases, tyrosine phosphorylation of paxillin, and integrin-mediated T cell adhesion to extracellular matrix glycoproteins. PMID:9307082

  13. Selectivity Profiling and Biological Activity of Novel β-Carbolines as Potent and Selective DYRK1 Kinase Inhibitors.

    Directory of Open Access Journals (Sweden)

    Katharina Rüben

    Full Text Available DYRK1A is a pleiotropic protein kinase with diverse functions in cellular regulation, including cell cycle control, neuronal differentiation, and synaptic transmission. Enhanced activity and overexpression of DYRK1A have been linked to altered brain development and function in Down syndrome and neurodegenerative diseases such as Alzheimer's disease. The β-carboline alkaloid harmine is a high affinity inhibitor of DYRK1A but suffers from the drawback of inhibiting monoamine oxidase A (MAO-A with even higher potency. Here we characterized a series of novel harmine analogs with minimal or absent MAO-A inhibitory activity. We identified several inhibitors with submicromolar potencies for DYRK1A and selectivity for DYRK1A and DYRK1B over the related kinases DYRK2 and HIPK2. An optimized inhibitor, AnnH75, inhibited CLK1, CLK4, and haspin/GSG2 as the only off-targets in a panel of 300 protein kinases. In cellular assays, AnnH75 dose-dependently reduced the phosphorylation of three known DYRK1A substrates (SF3B1, SEPT4, and tau without negative effects on cell viability. AnnH75 inhibited the cotranslational tyrosine autophosphorylation of DYRK1A and threonine phosphorylation of an exogenous substrate protein with similar potency. In conclusion, we have characterized an optimized β-carboline inhibitor as a highly selective chemical probe that complies with desirable properties of drug-like molecules and is suitable to interrogate the function of DYRK1A in biological studies.

  14. Selectivity Profiling and Biological Activity of Novel β-Carbolines as Potent and Selective DYRK1 Kinase Inhibitors.

    Science.gov (United States)

    Rüben, Katharina; Wurzlbauer, Anne; Walte, Agnes; Sippl, Wolfgang; Bracher, Franz; Becker, Walter

    2015-01-01

    DYRK1A is a pleiotropic protein kinase with diverse functions in cellular regulation, including cell cycle control, neuronal differentiation, and synaptic transmission. Enhanced activity and overexpression of DYRK1A have been linked to altered brain development and function in Down syndrome and neurodegenerative diseases such as Alzheimer's disease. The β-carboline alkaloid harmine is a high affinity inhibitor of DYRK1A but suffers from the drawback of inhibiting monoamine oxidase A (MAO-A) with even higher potency. Here we characterized a series of novel harmine analogs with minimal or absent MAO-A inhibitory activity. We identified several inhibitors with submicromolar potencies for DYRK1A and selectivity for DYRK1A and DYRK1B over the related kinases DYRK2 and HIPK2. An optimized inhibitor, AnnH75, inhibited CLK1, CLK4, and haspin/GSG2 as the only off-targets in a panel of 300 protein kinases. In cellular assays, AnnH75 dose-dependently reduced the phosphorylation of three known DYRK1A substrates (SF3B1, SEPT4, and tau) without negative effects on cell viability. AnnH75 inhibited the cotranslational tyrosine autophosphorylation of DYRK1A and threonine phosphorylation of an exogenous substrate protein with similar potency. In conclusion, we have characterized an optimized β-carboline inhibitor as a highly selective chemical probe that complies with desirable properties of drug-like molecules and is suitable to interrogate the function of DYRK1A in biological studies. PMID:26192590

  15. Structure-guided Inhibitor Design Expands the Scope of Analog-Sensitive Kinase Technology

    OpenAIRE

    Zhang, Chao; Lopez, Michael S.; Dar, Arvin C.; LaDow, Eva; Finkbeiner, Steven; Yun, Cai-Hong; Eck, Michael J; Shokat, Kevan M.

    2013-01-01

    Engineered analog-sensitive (AS) protein kinases have emerged as powerful tools for dissecting phospho-signaling pathways, for elucidating the cellular function of individual kinases, and for deciphering unanticipated effects of clinical therapeutics. A crucial and necessary feature of this technology is a bioorthogonal small molecule that is innocuous towards native cellular systems but can potently inhibit the engineered kinase. In order to generalize this method we sought a molecule capabl...

  16. Met tyrosine kinase inhibitor, PF-2341066, suppresses growth and invasion of nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Zhao Y

    2015-08-01

    Full Text Available Yuanyuan Zhao,1,* Jing Zhang,2,* Ying Tian,1,* Cong Xue,1 Zhihuang Hu,1 Li Zhang1,3 1Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, 2Department of Medical Oncology, the First Affiliated Hospital of Guang Zhou Traditional Chinese Medicine University, 3National Anti-Cancer Drug Research Centre, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China*These authors contributed equally to this work Purpose: We explored the effect of hepatocyte growth factor (HGF/Met signaling pathway on nasopharyngeal carcinoma (NPC cells in vitro and in vivo, and investigated the ability of Met tyrosine kinase inhibitor (TKI to block HGF-induced biological signaling.Experimental design: Met TKI inhibitor PF-2341066 alone, or in combination with cisplatin, was investigated for its ability to block HGF-induced signaling and biological effects in vitro and in vivo. HGF/Met expression and activation of signaling in NPC cells were detected by using Western blot and immunohistochemistry. Biological evaluation, including wound healing, cell proliferation, and invasion of NPC cells, was also examined, and the correlation between HGF/Met expression of primary and metastatic tumor in NPC patients and clinical prognosis were also analyzed.Results: Met TKI inhibitor, PF-2341066, inhibited growth of NPC cells in vivo with half maximal inhibitory concentration of 0.79±0.21 µmol/L, and suppressed invasion and migration of NPC cells; also, the inhibition of PF-2341066 was synergized with cisplatin treatment. Compared with the control group, Met TKI inhibited metastasis of transplanted NPC in nude mice (the number of live metastases [mean ± SD]: 5.8±2.2 versus 11.8±2.2, P=0.03; the number of lung metastases: 2.3±1.5 versus

  17. Mechanism of c-Met and EGFR tyrosine kinase inhibitor resistance through epithelial mesenchymal transition in non-small cell lung cancer.

    Science.gov (United States)

    Rastogi, Ichwaku; Rajanna, Supriya; Webb, Andrew; Chhabra, Gagan; Foster, Brad; Webb, Brian; Puri, Neelu

    2016-09-01

    According to currently available estimates from Cancer Research UK, 14.1 million new lung cancer cases were diagnosed and a staggering 8.2 million people worldwide died from lung cancer in 2012. EGFR and c-Met are two tyrosine kinase receptors most commonly overexpressed or mutated in Non-small Cell Lung Cancer (NSCLC) resulting in increased proliferation and survival of lung cancer cells. Tyrosine kinase inhibitors (TKIs), such as erlotinib, approved by the FDA as first/second line therapy for NSCLC patients have limited clinical efficacy due to acquired resistance. In this manuscript, we investigate and discuss the role of epithelial mesenchymal transition (EMT) in the development of resistance against EGFR and c-Met TKIs in NSCLC. Our findings show that Zeb-1, a transcriptional repressor of E-Cadherin, is upregulated in TKI-resistant cells causing EMT. We observed that TKI-resistant cells have increased gene and protein expression of EMT related proteins such as Vimentin, N-Cadherin, β-Catenin and Zeb-1, while expression of E-Cadherin, an important cell adhesion molecule, was suppressed. We also confirmed that TKI-resistant cells display mesenchymal cell type morphology, and have upregulation of β-Catenin which may regulate expression of Zeb-1, a transcriptional repressor of E-Cadherin in TKI-resistant NSCLC cells. Finally, we show that down-regulating Zeb-1 by inducing miR-200a or β-Catenin siRNA can increase drug sensitivity of TKI-resistant cells. PMID:27396618

  18. Progress of the mechanisms of focal adhesion kinase induced angiogenesis%黏着斑激酶促进血管生成机制的进展

    Institute of Scientific and Technical Information of China (English)

    李越; 林春龙

    2013-01-01

    黏着斑激酶(focal adhesion kinase,FAK)是一种胞质非受体蛋白酪氨酸激酶,在人、鸟、果蝇、鼠、非洲蟾蜍中均有表达并呈高度同源性.FAK在多器官和组织中均有表达,尤其是在肿瘤细胞中高水平表达.FAK介导的信号通路是细胞内各信号通路的交汇点,对正常细胞及肿瘤细胞黏附、迁移、增殖均起调控作用.在血管形成过程中,FAK可以通过FAK-Rho GTPases通路、FAK-PI3K通路等信号通路调节血管内皮细胞的黏附及迁移,调节细胞骨架重建.%Focal adhesion kinase (FAK) is a cytoplasmic non-receptor protein tyrosine kinase and has its expression in humans,birds,fruit flies,mice and xenopus with a high degree of homology.FAK has its expression as well in multiple organs and tissues,especially high expression in tumor cell.FAKmediated signal pathway is the intersection of all signal pathways,playing a regulatory role in the adhesion,migration and proliferation of both normal cells and the tumor cell.FAK can also through such signal pathways as FAK Rho GTPases pathway and FAK-PI3K pathway and etc.Regulate both the reconstruction of cytoskeleton and the adhesion and migration of vascular endothelial cells that is of great significance in that process.

  19. Tetrabromocinnamic acid (TBCA) and related compounds represent a new class of specific protein kinase CK2 inhibitors.

    Science.gov (United States)

    Pagano, Mario A; Poletto, Giorgia; Di Maira, Giovanni; Cozza, Giorgio; Ruzzene, Maria; Sarno, Stefania; Bain, Jenny; Elliott, Matthew; Moro, Stefano; Zagotto, Giuseppe; Meggio, Flavio; Pinna, Lorenzo A

    2007-01-01

    Abnormally high constitutive activity of protein kinase CK2, levels of which are elevated in a variety of tumours, is suspected to underlie its pathogenic potential. The most widely employed CK2 inhibitor is 4,5,6,7-tetrabromobenzotriazole (TBB), which exhibits a comparable efficacy toward another kinase, DYRK1 a. Here we describe the development of a new class of CK2 inhibitors, conceptually derived from TBB, which have lost their potency toward DYRK1 a. In particular, tetrabromocinnamic acid (TBCA) inhibits CK2 five times more efficiently than TBB (IC50 values 0.11 and 0.56 microM, respectively), without having any comparable effect on DYRK1 a (IC50 24.5 microM) or on a panel of 28 protein kinases. The usefulness of TBCA for cellular studies has been validated by showing that it reduces the viability of Jurkat cells more efficiently than TBB through enhancement of apoptosis. Collectively taken, the reported data support the view that suitably derivatized tetrabromobenzene molecules may provide powerful reagents for dissecting the cellular functions of CK2 and counteracting its pathogenic potentials. PMID:17133643

  20. Exploring the prominent performance of CX-4945 derivatives as protein kinase CK2 inhibitors by a combined computational study.

    Science.gov (United States)

    Wang, Xuwen; Pan, Peichen; Li, Youyong; Li, Dan; Hou, Tingjun

    2014-05-01

    Protein kinase CK2, also known as casein kinase II, is related to various cellular events and is a potential target for numerous cancers. In this study, we attempted to gain more insight into the inhibition process of CK2 by a series of CX-4945 derivatives through an integrated computational study that combines molecular docking, molecular dynamics (MD) simulations, and binding free energy calculations. Based on the binding poses predicted by molecular docking, the MD simulations were performed to explore the dynamic binding processes for ten selected inhibitors. Then, both Molecular Mechanics/Poisson Boltzmann Surface Area (MM/PBSA) and Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) techniques were employed to predict the binding affinities of the studied systems. The predicted binding energies of the selected inhibitors correlate well with their experimental activities (r(2) = 0.78). The van der Waals term is the most favorable component for the total energies. The free energy decomposition on a per residue basis reveals that the residue K68 is essential for the electrostatic interactions between CK2 and the studied inhibitors and numerous residues, including L45, V53, V66, F113, M163 and I174, play critical roles in forming van der Waals interactions with the inhibitors. Finally, a number of new derivatives were designed and the binding affinity and the predicted binding free energies of each designed molecule were obtained on the basis of molecular docking and MM/PBSA. It is expected that our research will benefit the future rational design of novel and potent inhibitors of CK2. PMID:24647611

  1. Identification and characterization of a small-molecule inhibitor of death-associated protein kinase 1

    DEFF Research Database (Denmark)

    Wilbek, Theis S; Skovgaard, Tine; Sorrell, Fiona J;

    2015-01-01

    A novel imidazo-pyramidazine inhibitor of DAPK1 that undergoes class-specific interactions and extends into the substrate recognition site has been identified. This inhibitor is a good starting point for the development of selective and potent inhibitors of DAPK1, with potential use against strok...

  2. Paroxetine Is a Direct Inhibitor of G Protein-Coupled Receptor Kinase 2 and Increases Myocardial Contractility

    Energy Technology Data Exchange (ETDEWEB)

    Thal, David M. [Univ. of Michigan, Ann Arbor, MI (United States); Homan, Kristoff T. [Univ. of Michigan, Ann Arbor, MI (United States); Chen, Jun [Univ. of New Mexico Health Sciences Center, Albuquerque, NM (United States); Wu, Emily K. [Univ. of Michigan, Ann Arbor, MI (United States); Hinkle, Patricia M. [Univ. of Rochester Medical Center, Rochester, NY (United States); Huang, Z. Maggie [Temple Univ. School of Medicine, Philadelphia, Pennsylvania (United States); Chuprun, J. Kurt [Temple Univ. School of Medicine, Philadelphia, Pennsylvania (United States); Song, Jianliang [Temple Univ. School of Medicine, Philadelphia, Pennsylvania (United States); Gao, Erhe [Temple Univ. School of Medicine, Philadelphia, Pennsylvania (United States); Cheung, Joseph Y. [Temple Univ. School of Medicine, Philadelphia, Pennsylvania (United States); Sklar, Larry A. [Univ. of New Mexico Health Sciences Center, Albuquerque, NM (United States); Koch, Walter J. [Temple Univ. School of Medicine, Philadelphia, Pennsylvania (United States); Tesmer, John J.G. [Univ. of Michigan, Ann Arbor, MI (United States)

    2012-08-10

    G protein-coupled receptor kinase 2 (GRK2) is a well-established therapeutic target for the treatment of heart failure. In this paper we identify the selective serotonin reuptake inhibitor (SSRI) paroxetine as a selective inhibitor of GRK2 activity both in vitro and in living cells. In the crystal structure of the GRK2·paroxetine–Gβγ complex, paroxetine binds in the active site of GRK2 and stabilizes the kinase domain in a novel conformation in which a unique regulatory loop forms part of the ligand binding site. Isolated cardiomyocytes show increased isoproterenol-induced shortening and contraction amplitude in the presence of paroxetine, and pretreatment of mice with paroxetine before isoproterenol significantly increases left ventricular inotropic reserve in vivo with no significant effect on heart rate. Neither is observed in the presence of the SSRI fluoxetine. Our structural and functional results validate a widely available drug as a selective chemical probe for GRK2 and represent a starting point for the rational design of more potent and specific GRK2 inhibitors.

  3. Synthesis of new pyrrolo[1,2-a]quinoxaline derivatives as potential inhibitors of Akt kinase.

    Science.gov (United States)

    Desplat, Vanessa; Geneste, Ambre; Begorre, Marc-Antoine; Fabre, Solene Belisle; Brajot, Stephane; Massip, Stephane; Thiolat, Denis; Mossalayi, Djavad; Jarry, Christian; Guillon, Jean

    2008-10-01

    Akt kinases are attractive targets for small molecule drug discovery because of their key role in tumor cell survival/proliferation and their overexpression/activation in many human cancers. Recent efforts in the development and biological evaluation of small molecule inhibitors of Akt have led to the identification of novel Akt kinase inhibitors, based on a quinoxaline or pyrazinone scaffold. A series of new substituted pyrrolo[1,2-a]quinoxaline derivatives, structural analogues of these active quinoxaline or pyrazinone pharmacophores, was synthesized from various substituted 2-nitroanilines or 1,2-phenylenediamine via multistep heterocyclization process. These new compounds were tested for their in vitro ability to inhibit the proliferation of the human leukemic cell lines K562, U937 and HL60, and the breast cancer cell line MCF7. Three of these human cell lines (K562, U937 and MCF7) exhibited an active phosphorylated Akt form. The most promising active pyrroloquinoxalines were found to be 1a that inhibited K562 cell line proliferation with an IC(50) of 4.5 microM, and 1h that inhibited U937 and MCF7 cell lines with IC(50) of 5 and 8 microM, respectively. These two candidates exhibited more potent activities than the reference inhibitor A6730.

  4. Several Human Cyclin-Dependent Kinase Inhibitors, Structurally Related to Roscovitine, As New Anti-Malarial Agents

    Directory of Open Access Journals (Sweden)

    Sandrine Houzé

    2014-09-01

    Full Text Available In Africa, malaria kills one child each minute. It is also responsible for about one million deaths worldwide each year. Plasmodium falciparum, is the protozoan responsible for the most lethal form of the disease, with resistance developing against the available anti-malarial drugs. Among newly proposed anti-malaria targets, are the P. falciparum cyclin-dependent kinases (PfCDKs. There are involved in different stages of the protozoan growth and development but share high sequence homology with human cyclin-dependent kinases (CDKs. We previously reported the synthesis of CDKs inhibitors that are structurally-related to (R-roscovitine, a 2,6,9-trisubstituted purine, and they showed activity against neuronal diseases and cancers. In this report, we describe the synthesis and the characterization of new CDK inhibitors, active in reducing the in vitro growth of P. falciparum (3D7 and 7G8 strains. Six compounds are more potent inhibitors than roscovitine, and three exhibited IC50 values close to 1 µM for both 3D7 and 7G8 strains. Although, such molecules do inhibit P. falciparum growth, they require further studies to improve their selectivity for PfCDKs.

  5. Biological and Molecular Effects of Small Molecule Kinase Inhibitors on Low-Passage Human Colorectal Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Falko Lange

    2014-01-01

    Full Text Available Low-passage cancer cell lines are versatile tools to study tumor cell biology. Here, we have employed four such cell lines, established from primary tumors of colorectal cancer (CRC patients, to evaluate effects of the small molecule kinase inhibitors (SMI vemurafenib, trametinib, perifosine, and regorafenib in an in vitro setting. The mutant BRAF (V600E/V600K inhibitor vemurafenib, but also the MEK1/2 inhibitor trametinib efficiently inhibited DNA synthesis, signaling through ERK1/2 and expression of genes downstream of ERK1/2 in BRAF mutant cells only. In case of the AKT inhibitor perifosine, three cell lines showed a high or intermediate responsiveness to the drug while one cell line was resistant. The multikinase inhibitor regorafenib inhibited proliferation of all CRC lines with similar efficiency and independent of the presence or absence of KRAS, BRAF, PIK3CA, and TP53 mutations. Regorafenib action was associated with broad-range inhibitory effects at the level of gene expression but not with a general inhibition of AKT or MEK/ERK signaling. In vemurafenib-sensitive cells, the antiproliferative effect of vemurafenib was enhanced by the other SMI. Together, our results provide insights into the determinants of SMI efficiencies in CRC cells and encourage the further use of low-passage CRC cell lines as preclinical models.

  6. The Sensitivity of Memory Consolidation and Reconsolidation to Inhibitors of Protein Synthesis and Kinases: Computational Analysis

    Science.gov (United States)

    Zhang, Yili; Smolen, Paul; Baxter, Douglas A.; Byrne, John H.

    2010-01-01

    Memory consolidation and reconsolidation require kinase activation and protein synthesis. Blocking either process during or shortly after training or recall disrupts memory stabilization, which suggests the existence of a critical time window during which these processes are necessary. Using a computational model of kinase synthesis and…

  7. Design and synthesis of novel benzoxazole analogs as Aurora B kinase inhibitors.

    Science.gov (United States)

    An, Ying; Lee, Eun; Yu, Yeongji; Yun, Jieun; Lee, Myeong Youl; Kang, Jong Soon; Kim, Woo-Young; Jeon, Raok

    2016-07-01

    A novel series of benzoxazole analogs was designed and synthesized, and their inhibitory activities against Aurora kinases were evaluated. Some of the tested compounds exhibited a promising activity with respect to the inhibition of Aurora B kinase. A structure-activity relationship study indicated that linker length, regiochemistry, and halogen substitution play important roles in kinase inhibitory potency. The binding modes between representative compounds and Aurora kinases were interpreted through a molecular docking study to explain the inhibitory activity and selectivity for Aurora A and B kinases. Compounds 13l and 13q also show an antiproliferative effect on the human tumor cell lines in a dose-dependent manner. The most potent 13q demonstrated good efficacy in the prostate cancer PC-3 tumor xenograft model.

  8. Synthesis, biological evaluation and molecular modeling studies of imidazo[1,2-a]pyridines derivatives as protein kinase inhibitors.

    Science.gov (United States)

    Lawson, Marie; Rodrigo, Jordi; Baratte, Blandine; Robert, Thomas; Delehouzé, Claire; Lozach, Olivier; Ruchaud, Sandrine; Bach, Stéphane; Brion, Jean-Daniel; Alami, Mouad; Hamze, Abdallah

    2016-11-10

    We report here the synthesis, the biological evaluation and the molecular modeling studies of new imidazo[1,2-a]pyridines derivatives designed as potent kinase inhibitors. This collection was obtained from 2-aminopyridines and 2-bromoacetophenone which afforded final compound in only one step. The bioactivity of this family of new compounds was tested using protein kinase and ATP competition assays. The structure-activity relationship (SAR) revealed that six compounds inhibit DYRK1A and CLK1 at a micromolar range. Docking studies provided possible explanations that correlate with the SAR data. The most active compound 4c inhibits CLK1 (IC50 of 0.7 μM) and DYRK1A (IC50 of 2.6 μM).

  9. PET imaging of early response to the tyrosine kinase inhibitor ZD4190

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Min [Jiangsu Institute of Nuclear Medicine, Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Wuxi, Jiangsu (China); National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), Bethesda, MD (United States); Gao, Haokao [National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), Bethesda, MD (United States); The Fourth Military Medical University, Department of Cardiology, Xijing Hospital, Xi' an (China); Yan, Yongjun; Sun, Xilin; Chen, Kai; Quan, Qimeng; Lang, Lixin; Kiesewetter, Dale; Niu, Gang; Chen, Xiaoyuan [National Institutes of Health (NIH), Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), Bethesda, MD (United States)

    2011-07-15

    We evaluated noninvasive positron emission tomography (PET) imaging for monitoring tumor response to the VEGFR-2 tyrosine kinase (TK) inhibitor ZD4190 during cancer therapy. Orthotopic MDA-MB-435 tumor-bearing mice were treated with ZD4190 (100 mg/kg orally per day for three consecutive days). Tumor growth was monitored by caliper measurement. During the therapeutic period, longitudinal PET scans were acquired using {sup 18}F-FDG, {sup 18}F-FLT and {sup 18}F-FPPRGD2 as imaging tracers to evaluate tumor glucose metabolism, tumor cell proliferation, and angiogenesis, respectively. Imaging metrics were validated by immunohistochemical analysis of Ki67, GLUT-1, F4/80, CD31, murine integrin {beta}3, and human integrin {alpha}v{beta}3. Three consecutive daily oral administrations of 100 mg/kg of ZD4190 were effective in delaying MDA-MB-435 tumor growth. A significant difference in tumor volume was observed on day 7 between the treatment group and the control group (p < 0.01). After the final treatment, tumor growth resumed after a short delay. In the control tumors, {sup 18}F-FPPRGD2 uptake was stable between days 0 and 7. In ZD4190-treated tumors, {sup 18}F-FPPRGD2 uptake had decreased significantly relative to baseline by 26.74{+-}8.12% (p < 0.05) on day 1 and by 41.19{+-}6.63% (p < 0.01) on day 3, then had returned to baseline on day 7. Tumor uptake of {sup 18}F-FLT had also decreased on both day 1 and day 3 after initiation of ZD4190 treatment. No significant change in {sup 18}F-FDG uptake in ZD4190-treated tumors was observed, however, compared with the control group. All of the imaging findings were supported by ex vivo analysis of related biomarkers. The longitudinal imaging results demonstrated the usefulness of quantitative {sup 18}F-FLT and {sup 18}F-FPPRGD2 PET imaging in evaluating the early antiproliferative and antiangiogenic effects of ZD4190. The quantification data from the PET imaging were consistent with the pattern of initial growth inhibition with

  10. Dacomitinib in lung cancer: a "lost generation" EGFR tyrosine-kinase inhibitor from a bygone era?

    Science.gov (United States)

    Ou, Sai-Hong Ignatius; Soo, Ross A

    2015-01-01

    EGFR tyrosine-kinase inhibitors (TKIs) have now been firmly established as the first-line treatment for non-small-cell lung cancer (NSCLC) patients harboring activating EGFR mutations, based on seven prospective randomized Phase III trials. However, despite significantly improved overall response rate and improved median progression-free survival when compared to platinum-doublet chemotherapy, EGFR-mutant NSCLC patients treated with EGFR TKIs invariably progress due to the emergence of acquired resistances, with the gatekeeper T790M mutation accounting for up to 60% of the resistance mechanisms. Second-generation irreversible EGFR TKIs were developed in part to inhibit the T790M mutation, in addition to the common activating EGFR mutations. Dacomitinib is one such second-generation EGFR TKI designed to inhibit both the wild-type (WT) EGFR and EGFR T790M. Afatinib is another second-generation EGR TKI that has been now been approved for the first-line treatment of EGFR-mutant NSCLC patients, while dacomitinib continues to undergo clinical evaluation. We will review the clinical development of dacomitinib from Phase I to Phase III trials, including the two recently published negative large-scale randomized Phase III trials (ARCHER 1009, NCIC-BR-26). Results from another large-scale randomized trial (ARCHER 1050) comparing dacomitinib to gefitinib as first-line treatment of advanced treatment-naïve EGFR-mutant NSCLC patients will soon be available and will serve as the lynchpin trial for the potential approval of dacomitinib in NSCLC. Meanwhile, third-generation EGFR TKIs (eg, CO-1686 [rociletinib], AZ9291, HM61713, EGF816, and ASP8273) that preferentially and potently inhibit EGFR T790M but not WT EGFR are in full-scale clinical development, and some of these EGFR TKIs have received "breakthrough" designation by the US Food and Drug Administration and will likely be approved in late 2015. Given the rapid development of third-generation EGFR TKIs and the approval of

  11. Augmentation of RANTES-induced extracellular signal-regulated kinase mediated signaling and T cell adhesion by elastase-treated fibronectin.

    Science.gov (United States)

    Brill, A; Hershkoviz, R; Vaday, G G; Chowers, Y; Lider, O

    2001-06-15

    T cells migrating across extracellular matrix (ECM) barriers toward their target, the inflammatory site, should respond to chemoattractant cytokines and to the degradation of ECM by specific enzymes. In this study, we examined the effects of RANTES and ECM proteins treated with human leukocyte elastase on T cell activation and adhesion to the ECM. We found that human peripheral blood T cells briefly suspended with RANTES (0.1-100 ng/ml) had increased phosphorylation of their intracellular extracellular signal-regulated kinase (ERK), a mitogen-activated protein kinase involved in the activation of several intracellular downstream effector molecules implicated in cell adhesion and migration. Consequently, a small portion (12-20%) of the responding cells adhered to fibronectin (FN). However, when the T cells were exposed to RANTES in the presence of native immobilized FN, laminin, or collagen type I, ERK phosphorylation was partially inhibited, suggesting that this form of the ECM proteins can down-regulate RANTES-induced intracellular signaling. In contrast, when the T cells were exposed to RANTES in the presence of elastase-treated immobilized FN, but not to elastase-treated laminin, ERK phosphorylation was markedly increased. Furthermore, a large percentage (30%) of RANTES-activated T cells adhered to the enzymatically treated FN in a beta1 integrin-dependent fashion. Thus, while migrating along chemotactic gradients within the ECM, T cells can adapt their adhesive performance according to the level of cleavage induced by enzymes to the matrix. PMID:11390457

  12. Prediction of cyclin-dependent kinase 2 inhibitor potency using the fragment molecular orbital method

    Directory of Open Access Journals (Sweden)

    Mazanetz Michael P

    2011-01-01

    Full Text Available Abstract Background The reliable and robust estimation of ligand binding affinity continues to be a challenge in drug design. Many current methods rely on molecular mechanics (MM calculations which do not fully explain complex molecular interactions. Full quantum mechanical (QM computation of the electronic state of protein-ligand complexes has recently become possible by the latest advances in the development of linear-scaling QM methods such as the ab initio fragment molecular orbital (FMO method. This approximate molecular orbital method is sufficiently fast that it can be incorporated into the development cycle during structure-based drug design for the reliable estimation of ligand binding affinity. Additionally, the FMO method can be combined with approximations for entropy and solvation to make it applicable for binding affinity prediction for a broad range of target and chemotypes. Results We applied this method to examine the binding affinity for a series of published cyclin-dependent kinase 2 (CDK2 inhibitors. We calculated the binding affinity for 28 CDK2 inhibitors using the ab initio FMO method based on a number of X-ray crystal structures. The sum of the pair interaction energies (PIE was calculated and used to explain the gas-phase enthalpic contribution to binding. The correlation of the ligand potencies to the protein-ligand interaction energies gained from FMO was examined and was seen to give a good correlation which outperformed three MM force field based scoring functions used to appoximate the free energy of binding. Although the FMO calculation allows for the enthalpic component of binding interactions to be understood at the quantum level, as it is an in vacuo single point calculation, the entropic component and solvation terms are neglected. For this reason a more accurate and predictive estimate for binding free energy was desired. Therefore, additional terms used to describe the protein-ligand interactions were then

  13. Killing of Cancer Cells by the Photoactivatable Protein Kinase C Inhibitor, Calphostin C, Involves Induction of Endoplasmic Reticulum Stress

    Directory of Open Access Journals (Sweden)

    Aparna Kaul

    2009-09-01

    Full Text Available Calphostin C (cal-C is a photoactivatable inhibitor that binds to the regulatory domain of protein kinase C (PKC and to other proteins that contain diacylglycerol/phorbol ester binding sites. Cal-C is cytotoxic against many types of cancer cells, yet the basis for this activity remains poorly understood. Here, we show that one of the earliest effects of cal-C is an impairment of glycoprotein export from the endoplasmic reticulum (ER, accompanied by formation of ER-derived vacuoles. Vacuolization of the ER is correlated with induction of an ER stress response that includes activation of c-Jun N-terminal kinase and protein kinase R-like ER kinase, as well as increased expression of CCAAT/enhancer binding protein homologous transcription factor (CHOP; GADD153. These effects of cal-C are not mimicked by staurosporine, an inhibitor of PKC catalytic activity, indicating that ER stress is due to interaction of cal-C with targets other than PKC. In conjunction with the induction of ER stress, breast carcinoma cells undergo caspase-dependent cell death with early activation of caspases 9 and 7 and cleavage of poly(ADP-ribosepolymerase. Reduction of CHOP expression by short hairpin RNA decreases the sensitivity of the cells to cal-C, suggesting that induction of apoptosis by cal-C is related, at least in part, to ER stress triggered by disruption of ER morphology and transport function. Antineoplastic drugs that work by inducting ER stress have shown promise in preclinical and clinical trials. Thus, the present findings raise the possibility that cal-C may be useful for photodynamic therapy based on induction of ER stress in some forms of cancer.

  14. Epigallocatechin gallate (EGCG), a major component of green tea, is a dual phosphoinositide-3-kinase/mTOR inhibitor

    International Nuclear Information System (INIS)

    Research highlights: → Epigallocatechin-3-gallate (EGCG) is an ATP-competitive inhibitor of PI3K and mTOR with Ki values around 300 nM. → EGCG inhibits cell proliferation and AKT phosphorylation at Ser473 in MDA-MB-231and A549 cells. → Molecular docking studies show that EGCG binds well to the PI3K kinase domain active site. → These results suggest another important molecular mechanism for the anticancer activities of EGCG. -- Abstract: The PI3K signaling pathway is activated in a broad spectrum of human cancers, either directly by genetic mutation or indirectly via activation of receptor tyrosine kinases or inactivation of the PTEN tumor suppressor. The key nodes of this pathway have emerged as important therapeutic targets for the treatment of cancer. In this study, we show that (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea, is an ATP-competitive inhibitor of both phosphoinositide-3-kinase (PI3K) and mammalian target of rapamycin (mTOR) with Ki values of 380 and 320 nM respectively. The potency of EGCG against PI3K and mTOR is within physiologically relevant concentrations. In addition, EGCG inhibits cell proliferation and AKT phosphorylation at Ser473 in MDA-MB-231 and A549 cells. Molecular docking studies show that EGCG binds well to the PI3K kinase domain active site, agreeing with the finding that EGCG competes for ATP binding. Our results suggest another important molecular mechanism for the anticancer activities of EGCG.

  15. Alignment independent 3D-QSAR, quantum calculations and molecular docking of Mer specific tyrosine kinase inhibitors as anticancer drugs

    Directory of Open Access Journals (Sweden)

    Fereshteh Shiri

    2016-03-01

    Full Text Available Mer receptor tyrosine kinase is a promising novel cancer therapeutic target in many human cancers, because abnormal activation of Mer has been implicated in survival signaling and chemoresistance. 3D-QSAR analyses based on alignment independent descriptors were performed on a series of 81 Mer specific tyrosine kinase inhibitors. The fractional factorial design (FFD and the enhanced replacement method (ERM were applied and tested as variable selection algorithms for the selection of optimal subsets of molecular descriptors from a much greater pool of such regression variables. The data set was split into 65 molecules as the training set and 16 compounds as the test set. All descriptors were generated by using the GRid INdependent descriptors (GRIND approach. After variable selection, GRIND were correlated with activity values (pIC50 by PLS regression. Of the two applied variable selection methods, ERM had a noticeable improvement on the statistical parameters of PLS model, and yielded a q2 value of 0.77, an rpred2 of 0.94, and a low RMSEP value of 0.25. The GRIND information contents influencing the affinity on Mer specific tyrosine kinase were also confirmed by docking studies. In a quantum calculation study, the energy difference between HOMO and LUMO (gap implied the high interaction of the most active molecule in the active site of the protein. In addition, the molecular electrostatic potential energy at DFT level confirmed results obtained from the molecular docking. The identified key features obtained from the molecular modeling, enabled us to design novel kinase inhibitors.

  16. Proliferation of Ewing sarcoma cell lines is suppressed by the receptor tyrosine kinase inhibitors gefitinib and vandetanib

    Directory of Open Access Journals (Sweden)

    Åman Pierre

    2008-01-01

    Full Text Available Abstract Background Tyrosine kinase inhibitors (TKIs have gained much attention in recent years as targeted agents for the treatment of a wide range of human cancers. We have investigated the effect of the TKIs gefitinib and vandetanib on tumor cell lines derived from Ewing sarcoma, a highly malignant tumor affecting bone and soft tissue in children and young adults. Gefitinib is an inhibitor of epidermal growth factor receptor tyrosine kinase activity (EGFR and vandetanib selectively targets vascular endothelial growth factor receptor-2 (VEGFR-2 with additional activity against VEGFR-3, EGFR and RET kinase receptors. Results Two Ewing sarcoma cell lines investigated showed high levels of nuclear EGFR expression as well as moderate expression in plasma membrane and cytoplasm. When treated with concentrations of 5 μM and more of either gefitinib or vandetanib, we observed a significant decrease in cell proliferation. However, there were no detectable changes in p44/42 MAPK and Akt-1 phosphorylation, or in the expression of cyclin D1 or c-Myc following gefitinib or vandetanib treatment. Conclusion We conclude that Ewing sarcoma tumor cell proliferation is not highly sensitive to inhibition of EGFR signaling alone or the simultaneous inhibition of VEGFR receptors, EGFR and RET kinase. Decreased tumor cell proliferation could be achieved with gefitinib and vandetanib, but only at higher doses where non-specific effects of the compounds may be overriding. As Ewing tumor cells do not seem to depend on EGFR and VEGFR pathways for survival, other key factors in the cellular signaling of Ewing sarcoma should be targeted in order to obtain a potent therapeutic response.

  17. Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

    International Nuclear Information System (INIS)

    Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC50 values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets

  18. Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tajima, Shigeru [Department of Virology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo 162-8640 (Japan); Hikono, Hirokazu; Saito, Takehiko [Influenza and Prion Disease Research Center, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan); Aida, Yoko, E-mail: aida@riken.jp [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2014-07-18

    Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC{sub 50} values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets.

  19. Epigallocatechin gallate (EGCG), a major component of green tea, is a dual phosphoinositide-3-kinase/mTOR inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Van Aller, Glenn S., E-mail: glenn.s.van.aller@gsk.com [Department of Cancer Research, GlaxoSmithKline, Collegeville, PA 19426 (United States); Carson, Jeff D. [Department of Cancer Research, GlaxoSmithKline, Collegeville, PA 19426 (United States); Tang, Wei; Peng, Hao; Zhao, Lin [Discovery Biology, BioDuro, No. 29 Life Science Park Road, Changping, Beijing (China); Copeland, Robert A.; Tummino, Peter J. [Department of Cancer Research, GlaxoSmithKline, Collegeville, PA 19426 (United States); Luo, Lusong [Discovery Biology, BioDuro, No. 29 Life Science Park Road, Changping, Beijing (China)

    2011-03-11

    Research highlights: {yields} Epigallocatechin-3-gallate (EGCG) is an ATP-competitive inhibitor of PI3K and mTOR with Ki values around 300 nM. {yields} EGCG inhibits cell proliferation and AKT phosphorylation at Ser473 in MDA-MB-231and A549 cells. {yields} Molecular docking studies show that EGCG binds well to the PI3K kinase domain active site. {yields} These results suggest another important molecular mechanism for the anticancer activities of EGCG. -- Abstract: The PI3K signaling pathway is activated in a broad spectrum of human cancers, either directly by genetic mutation or indirectly via activation of receptor tyrosine kinases or inactivation of the PTEN tumor suppressor. The key nodes of this pathway have emerged as important therapeutic targets for the treatment of cancer. In this study, we show that (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea, is an ATP-competitive inhibitor of both phosphoinositide-3-kinase (PI3K) and mammalian target of rapamycin (mTOR) with K{sub i} values of 380 and 320 nM respectively. The potency of EGCG against PI3K and mTOR is within physiologically relevant concentrations. In addition, EGCG inhibits cell proliferation and AKT phosphorylation at Ser473 in MDA-MB-231 and A549 cells. Molecular docking studies show that EGCG binds well to the PI3K kinase domain active site, agreeing with the finding that EGCG competes for ATP binding. Our results suggest another important molecular mechanism for the anticancer activities of EGCG.

  20. Discovery of the first non-ATP competitive IGF-1R kinase inhibitors: advantages in comparison with competitive inhibitors.

    Science.gov (United States)

    Lesuisse, Dominique; Mauger, Jacques; Nemecek, Conception; Maignan, Sébastien; Boiziau, Janine; Harlow, Greg; Hittinger, Augustin; Ruf, Swen; Strobel, Hartmut; Nair, Anil; Ritter, Kurt; Malleron, Jean-Luc; Dagallier, Anne; El-Ahmad, Youssef; Guilloteau, Jean-Pierre; Guizani, Houlfa; Bouchard, Hervé; Venot, Corinne

    2011-04-15

    A new series of IGF-1R inhibitors related to hydantoins were identified from a lead originating from HTS. Their noncompetitive property as well as their slow binding characteristics provided a series of compounds with unique selectivity and excellent cellular activities.

  1. A fully automated two-step synthesis of an {sup 18}F-labelled tyrosine kinase inhibitor for EGFR kinase activity imaging in tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kobus, D.; Giesen, Y.; Ullrich, R.; Backes, H. [Max Planck Institute for Neurological Research with Klaus-Joachim-Zuelch Laboratories of the Max Planck Society and the Faculty of Medicine of the University of Cologne, Cologne (Germany); Neumaier, B. [Max Planck Institute for Neurological Research with Klaus-Joachim-Zuelch Laboratories of the Max Planck Society and the Faculty of Medicine of the University of Cologne, Cologne (Germany)], E-mail: bernd.neumaier@nf.mpg.de

    2009-11-15

    Radiolabelled epidermal growth factor receptor (EGFR) tyrosine kinase (TK) inhibitors potentially facilitate the assessment of EGFR overexpression in tumors. Since elaborate multi-step radiosyntheses are required for {sup 18}F-labelling of EGFR-specific anilinoquinazolines we report on the development of a two-step click labelling approach that was adapted to a fully automated synthesis module. 6-(4-N,N-Dimethylaminocrotonyl)amido-4-(3-chloro-4-fluoro)phenylamino-7-{l_brace}3- [4-(2-[{sup 18}F]fluoroethyl)-2,3,4-triazol-1-yl]propoxy{r_brace}quinazoline ([{sup 18}F]6) was synthesized via Huisgen 1,3-dipolar cycloaddition between 2-[{sup 18}F]fluoroethylazide ([{sup 18}F]4) and the alkyne modified anilinoquinazoline precursor 5. PET images of PC9 tumor xenograft using the novel biomarker showed promising results to visualize EGFR overexpression.

  2. Z3, a Novel Jak2 Tyrosine Kinase Small Molecule Inhibitor that Suppresses Jak2-mediated Pathologic Cell Growth

    OpenAIRE

    Sayyah, Jacqueline; Magis, Andrew; Ostrov, David A; Robert W Allan; Braylan, Raul C.; Sayeski, Peter P.

    2008-01-01

    Jak2 tyrosine kinase is essential for animal development and hyper-kinetic Jak2 function has been linked to a host of human diseases. Control of this pathway using Jak2-specific inhibitors would therefore potentially serve as a useful research tool and/or therapeutic agent. Here, we used a high throughput program called DOCK, to predict the ability of 20,000 small molecules to interact with a structural pocket adjacent to the ATP binding site of murine Jak2. One small molecule, 2-methyl-1-phe...

  3. Induction of apoptosis in cancer cells by tumor necrosis factor and butyrolactone, an inhibitor of cyclin-dependent kinases

    OpenAIRE

    Belizário, J E; S. Sherwood; Beçak, W.

    1999-01-01

    Induction of apoptosis by tumor necrosis factor (TNF) is modulated by changes in the expression and activity of several cell cycle regulatory proteins. We examined the effects of TNF (1-100 ng/ml) and butyrolactone I (100 µM), a specific inhibitor of cyclin-dependent kinases (CDK) with high selectivity for CDK-1 and CDK-2, on three different cancer cell lines: WEHI, L929 and HeLa S3. Both compounds blocked cell growth, but only TNF induced the common events of apoptosis, i.e., chromatin conde...

  4. Puquitinib mesylate, an inhibitor of phosphatidylinositol 3-kinase p110δ, for treating relapsed or refractory non-Hodgkin's lymphoma

    OpenAIRE

    Yang, Hang; Wang, Yu; Zhan, Jing; Xia, Yi; Sun, Peng; Bi, Xi-wen; Liu, Pan-pan; Li, Zhi-Ming; Li, Su; Zou, Ben-Yan; Jiang, Wen-qi

    2015-01-01

    Objectives To determine the safety of Puquitinib Mesylate (XC-302), an oral inhibitor of phosphatidylinositol 3-kinase, in treating relapsed or refractory non-Hodgkin's lymphoma (NHL). Methods Between October 2013 and July 2015, 21 patients from Sun Yat-sen University Cancer Center were treated twice daily on each day of a 28-day cycle (median number of cycles, 2; maximum, 20) with XC-302 at a post prandial dose of 25 mg, 37.5 mg, or 50 mg. Adverse events (AEs), AUClast and Cmax, response rat...

  5. Substituted N-aryl-6-pyrimidinones: A new class of potent, selective, and orally active p38 MAP kinase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Devadas, Balekudru; Selness, Shaun R.; Xing, Li; Madsen, Heather M.; Marrufo, Laura D.; Shieh, Huey; Messing, Dean M.; Yang, Jerry Z.; Morgan, Heidi M.; Anderson, Gary D.; Webb, Elizabeth G.; Zhang, Jian; Devraj, Rajesh V.; Monahan, Joseph B. (Pfizer)

    2012-02-28

    A novel series of highly potent and selective p38 MAP kinase inhibitors was developed originating from a substituted N-aryl-6-pyrimidinone scaffold. SAR studies coupled with in vivo evaluations in rat arthritis model culminated in the identification of 10 with excellent oral efficacy. Compound 10 exhibited a significantly enhanced dissolution rate compared to 1, translating to a high oral bioavailability (>90%) in rat. In animal studies 10 inhibited LPS-stimulated production of tumor necrosis factor-{alpha} in a dose-dependent manner and demonstrated robust efficacy comparable to dexamethasone in a rat streptococcal cell wall-induced arthritis model.

  6. Aldosterone stimulates nuclear factor-kappa B activity and transcription of intercellular adhesion molecule-1 and connective tissue growth factor in rat mesangial cells via serum- and glucocorticoid-inducible protein kinase-1.

    Science.gov (United States)

    Terada, Yoshio; Ueda, Satoko; Hamada, Kazu; Shimamura, Yoshiko; Ogata, Koji; Inoue, Kosuke; Taniguchi, Yoshinori; Kagawa, Toru; Horino, Taro; Takao, Toshihiro

    2012-02-01

    Several clinical and experimental data support the hypothesis that aldosterone contributes to the progression of renal injury. To determine the signaling pathway of aldosterone in relation to fibrosis and inflammation in mesangial cells, we investigated the effects of aldosterone on expression and activation of serum- and glucocorticoid-inducible protein kinase-1 (SGK1), the activation of nuclear factor-kappa B (NF-κB activation, and the expressions of intercellular adhesion molecule-1 (ICAM-1) and connective tissue growth factor (CTGF). Aldosterone stimulated SGK1 expression, phosphorylation (Ser-256), and kinase activity. The increments of phosphorylation and expression of SGK1 induced by aldosterone were inhibited by mineralocorticoid receptor (MR) inhibitor (eplerenone). Aldosterone stimulated NF-κB activity measured by NF-κB responsive elements, luciferase assay, and the levels of inhibitor of kappa B (IκB) phosphorylation. This aldosterone-induced activation of NF-κB was inhibited by the transfection of dominant-negative SGK1. Furthermore, aldosterone augmented the promoter activities and protein expressions of ICAM-1 and CTGF. The effects of aldosterone on ICAM-1 and CTGF promoter activities and protein expressions were inhibited by the transfection of dominant-negative SGK1 and dominant-negative IκBα. We also found that the MR antagonist significantly ameliorated the glomerular injury and enhancements in SGK1, ICAM-1, and CTGF expressions induced by 1% sodium chloride and aldosterone in vivo. In conclusion, our findings suggest that aldosterone stimulates ICAM-1 and CTGF transcription via activation of SGK1 and NF-κB, which may be involved in the progression of aldosterone-induced mesangial fibrosis and inflammation. MR antagonists may serve as useful therapeutic targets for the treatment of glomerular inflammatory disease.

  7. MDM2 Inhibitor, Nutlin 3a, Induces p53 Dependent Autophagy in Acute Leukemia by AMP Kinase Activation.

    Directory of Open Access Journals (Sweden)

    Gautam Borthakur

    Full Text Available MDM2 (mouse double minute 2 inhibitors that activate p53 and induce apoptosis in a non-genotoxic manner are in clinical development for treatment of leukemias. P53 can modulate other programmed cell death pathways including autophagy both transcriptionally and non-transcriptionally. We investigated autophagy induction in acute leukemia by Nutlin 3a, a first-in-class MDM2 inhibitor. Nutlin 3a induced autophagy in a p53 dependent manner and transcriptional activation of AMP kinase (AMPK is critical, as this effect is abrogated in AMPK -/- mouse embryonic fibroblasts. Nutlin 3a induced autophagy appears to be pro-apoptotic as pharmacological (bafilomycin or genetic inhibition (BECLIN1 knockdown of autophagy impairs apoptosis induced by Nutlin 3a.

  8. An orally available tyrosine kinase ALK and RET dual inhibitor bearing the tetracyclic benzo[b]carbazolone core.

    Science.gov (United States)

    Song, Zilan; Xia, Zongjun; Ji, Yinchun; Xing, Li; Gao, Yinglei; Ai, Jing; Geng, Meiyu; Zhang, Ao

    2016-08-01

    Our early structure-activity relationship study has identified benzo[b]carbazolone 6 as a high potency orally bioavailable ALK inhibitor. Further lead profiling disclosed that 6 is active against both ALK resistant and hot spot-activating mutants, and is also highly potent against RET kinase. Tumor stasis and partial tumor regression were achieved with 6 in both NIH/3T3-EML4-ALK and NIH/3T3-EML4-ALK L1196M xenograft models. Based on the optimal in vitro and in vivo antitumor efficacy, compound 6 is now being profiled further in our preclinical settings as a new orally available ALK/RET dual inhibitor. PMID:27131066

  9. The Rho kinase inhibitor Fasudil up-regulates astrocytic glutamate transport subsequent to actin remodelling in murine cultured astrocytes

    DEFF Research Database (Denmark)

    Lau, Cl; O'Shea, Rd; Bischof, L;

    2011-01-01

    BACKGROUND AND PURPOSE Glutamate transporters play a major role in maintaining brain homeostasis and the astrocytic transporters, EAAT1 and EAAT2, are functionally dominant. Astrocytic excitatory amino acid transporters (EAATs) play important roles in various neuropathologies wherein astrocytes...... undergo cytoskeletal changes. Astrocytic plasticity is well documented, but the interface between EAAT function, actin and the astrocytic cytoskeleton is poorly understood. Because Rho kinase (ROCK) is a key determinant of actin polymerization, we investigated the effects of ROCK inhibitors on EAAT...... activity and astrocytic morphology. EXPERIMENTAL APPROACH The functional activity of glutamate transport was determined in murine cultured astrocytes after exposure to the ROCK inhibitors Fasudil (HA-1077) and Y27632 using biochemical, molecular and morphological approaches. Cytochemical analyses assessed...

  10. Clonal evolution of AML on novel FMS-like tyrosine kinase-3 (FLT3 inhibitor therapy with evolving actionable targets

    Directory of Open Access Journals (Sweden)

    Pashtoon M. Kasi

    2016-01-01

    Full Text Available For acute myeloid leukemia (AML, identification of activating mutations in the FMS-like tyrosine kinase-3 (FLT3 has led to the development of several FLT3-inhibitors. Here we present clinical and next generation sequencing data at the time of progression of a patient on a novel FLT3-inhibitor clinical trial (ASP2215 to show that employing therapeutic interventions with these novel targeted therapies can lead to consequences secondary to selective pressure and clonal evolution of cancer. We describe novel findings alongside data on treatment directed towards actionable aberrations acquired during the process. (Clinical Trial: NCT02014558; registered at: 〈https://clinicaltrials.gov/ct2/show/NCT02014558〉

  11. Discovery of Novel 3-Quinoline Carboxamides as Potent, Selective, and Orally Bioavailable Inhibitors of Ataxia Telangiectasia Mutated (ATM) Kinase.

    Science.gov (United States)

    Degorce, Sébastien L; Barlaam, Bernard; Cadogan, Elaine; Dishington, Allan; Ducray, Richard; Glossop, Steven C; Hassall, Lorraine A; Lach, Franck; Lau, Alan; McGuire, Thomas M; Nowak, Thorsten; Ouvry, Gilles; Pike, Kurt G; Thomason, Andrew G

    2016-07-14

    A novel series of 3-quinoline carboxamides has been discovered and optimized as selective inhibitors of the ataxia telangiectasia mutated (ATM) kinase. From a modestly potent HTS hit (4), we identified molecules such as 6-[6-(methoxymethyl)-3-pyridinyl]-4-{[(1R)-1-(tetrahydro-2H-pyran-4-yl)ethyl]amino}-3-quinolinecarboxamide (72) and 7-fluoro-6-[6-(methoxymethyl)pyridin-3-yl]-4-{[(1S)-1-(1-methyl-1H-pyrazol-3-yl)ethyl]amino}quinoline-3-carboxamide (74) as potent and highly selective ATM inhibitors with overall ADME properties suitable for oral administration. 72 and 74 constitute excellent oral tools to probe ATM inhibition in vivo. Efficacy in combination with the DSB-inducing agent irinotecan was observed in a disease relevant model. PMID:27259031

  12. Identification of a DYRK1A Inhibitor that Induces Degradation of the Target Kinase using Co-chaperone CDC37 fused with Luciferase nanoKAZ.

    Science.gov (United States)

    Sonamoto, Rie; Kii, Isao; Koike, Yuka; Sumida, Yuto; Kato-Sumida, Tomoe; Okuno, Yukiko; Hosoya, Takamitsu; Hagiwara, Masatoshi

    2015-01-01

    The protein kinase family includes attractive targets for drug development. Methods for screening of kinase inhibitors remain largely limited to in vitro catalytic assays. It has been shown that ATP-competitive inhibitors antagonize interaction between the target kinase and kinase-specific co-chaperone CDC37 in living cells. Here we show a cell-based method to screen kinase inhibitors using fusion protein of CDC37 with a mutated catalytic 19-kDa component of Oplophorus luciferase, nanoKAZ (CDC37-nanoKAZ). A dual-specificity kinase DYRK1A, an importance of which has been highlighted in Alzheimer's disease, was targeted in this study. We established 293T cells stably expressing CDC37-nanoKAZ, and analyzed interaction between CDC37-nanoKAZ and DYRK1A. We revealed that DYRK1A interacted with CDC37-nanoKAZ. Importantly, point mutations that affect autophosphorylation strengthened the interaction, thus improving signal/noise ratio of the interaction relative to non-specific binding of CDC37-nanoKAZ. This high signal/noise ratio enabled screening of chemical library that resulted in identification of a potent inhibitor of DYRK1A, named CaNDY. CaNDY induced selective degradation of DYRK1A, and inhibited catalytic activity of recombinant DYRK1A with IC50 value of 7.9 nM by competing with ATP. This method based on a mutant target kinase and a bioluminescence-eliciting co-chaperone CDC37 could be applicable to evaluation and development of inhibitors targeting other kinases. PMID:26234946

  13. Characterisation of biological effects of a novel protein kinase D inhibitor in endothelial cells

    OpenAIRE

    Evans, Ian M; Bagherzadeh, Azadeh; Charles, Mark; Raynham, Tony; Ireson, Chris; Boakes, Alexandra; Kelland, Lloyd; Ian C. Zachary

    2010-01-01

    VEGF (vascular endothelial growth factor) plays an essential role in angiogenesis during development and in disease largely mediated by signalling events initiated by binding of VEGF to its receptor, VEGFR2 (VEGF receptor 2)/KDR (kinase insert domain receptor). Recent studies indicate that VEGF activates PKD (protein kinase D) in endothelial cells to regulate a variety of cellular functions, including signalling events, proliferation, migration and angiogenesis. To better understand the role ...

  14. Repositioning of a cyclin-dependent kinase inhibitor GW8510 as a ribonucleotide reductase M2 inhibitor to treat human colorectal cancer.

    Science.gov (United States)

    Hsieh, Y-Y; Chou, C-J; Lo, H-L; Yang, P-M

    2016-01-01

    Colorectal cancer (CRC) is the second leading cause of cancer-related death in males and females in the world. It is of immediate importance to develop novel therapeutics. Human ribonucleotide reductase (RRM1/RRM2) has an essential role in converting ribonucleoside diphosphate to 2'-deoxyribonucleoside diphosphate to maintain the homeostasis of nucleotide pools. RRM2 is a prognostic biomarker and predicts poor survival of CRC. In addition, increased RRM2 activity is associated with malignant transformation and tumor cell growth. Bioinformatics analyses show that RRM2 was overexpressed in CRC and might be an attractive target for treating CRC. Therefore, we attempted to search novel RRM2 inhibitors by using a gene expression signature-based approach, connectivity MAP (CMAP). The result predicted GW8510, a cyclin-dependent kinase inhibitor, as a potential RRM2 inhibitor. Western blot analysis indicated that GW8510 inhibited RRM2 expression through promoting its proteasomal degradation. In addition, GW8510 induced autophagic cell death. In addition, the sensitivities of CRC cells to GW8510 were associated with the levels of RRM2 and endogenous autophagic flux. Taken together, our study indicates that GW8510 could be a potential anti-CRC agent through targeting RRM2. PMID:27551518

  15. Molecular Determinants Underlying Binding Specificities of the ABL Kinase Inhibitors: Combining Alanine Scanning of Binding Hot Spots with Network Analysis of Residue Interactions and Coevolution.

    Directory of Open Access Journals (Sweden)

    Amanda Tse

    Full Text Available Quantifying binding specificity and drug resistance of protein kinase inhibitors is of fundamental importance and remains highly challenging due to complex interplay of structural and thermodynamic factors. In this work, molecular simulations and computational alanine scanning are combined with the network-based approaches to characterize molecular determinants underlying binding specificities of the ABL kinase inhibitors. The proposed theoretical framework unveiled a relationship between ligand binding and inhibitor-mediated changes in the residue interaction networks. By using topological parameters, we have described the organization of the residue interaction networks and networks of coevolving residues in the ABL kinase structures. This analysis has shown that functionally critical regulatory residues can simultaneously embody strong coevolutionary signal and high network centrality with a propensity to be energetic hot spots for drug binding. We have found that selective (Nilotinib and promiscuous (Bosutinib, Dasatinib kinase inhibitors can use their energetic hot spots to differentially modulate stability of the residue interaction networks, thus inhibiting or promoting conformational equilibrium between inactive and active states. According to our results, Nilotinib binding may induce a significant network-bridging effect and enhance centrality of the hot spot residues that stabilize structural environment favored by the specific kinase form. In contrast, Bosutinib and Dasatinib can incur modest changes in the residue interaction network in which ligand binding is primarily coupled only with the identity of the gate-keeper residue. These factors may promote structural adaptability of the active kinase states in binding with these promiscuous inhibitors. Our results have related ligand-induced changes in the residue interaction networks with drug resistance effects, showing that network robustness may be compromised by targeted mutations

  16. Splenomegaly in myelofibrosis—new options for therapy and the therapeutic potential of Janus kinase 2 inhibitors

    Directory of Open Access Journals (Sweden)

    Randhawa Jasleen

    2012-08-01

    Full Text Available Abstract Splenomegaly is a common sign of primary myelofibrosis (PMF, post-polycythemia vera myelofibrosis (post-PV MF, and post-essential thrombocythemia myelofibrosis (post-ET MF that is associated with bothersome symptoms, which have a significant negative impact on patients’ quality of life. It may also be present in patients with advanced polycythemia vera (PV or essential thrombocythemia (ET. Until recently, none of the therapies used to treat MF were particularly effective in reducing splenomegaly. The discovery of an activating Janus kinase 2 (JAK2 activating mutation (JAK2V617F that is present in almost all patients with PV and in about 50-60 % of patients with ET and PMF led to the initiation of several trials investigating the clinical effectiveness of various JAK2 (or JAK1/JAK2 inhibitors for the treatment of patients with ET, PV, and MF. Some of these trials have documented significant clinical benefit of JAK inhibitors, particularly in terms of regression of splenomegaly. In November 2011, the US Food and Drug Administration approved the use of the JAK1- and JAK2-selective inhibitor ruxolitinib for the treatment of patients with intermediate or high-risk myelofibrosis, including PMF, post-PV MF, and post-ET MF. This review discusses current therapeutic options for splenomegaly associated with primary or secondary MF and the treatment potential of the JAK inhibitors in this setting.

  17. Protein kinase C betaII peptide inhibitor exerts cardioprotective effects in rat cardiac ischemia/reperfusion injury.

    Science.gov (United States)

    Omiyi, Didi; Brue, Richard J; Taormina, Philip; Harvey, Margaret; Atkinson, Norrell; Young, Lindon H

    2005-08-01

    Ischemia followed by reperfusion (I/R) in the presence of polymorphonuclear leukocytes (PMNs) results in a marked cardiac contractile dysfunction. A cell-permeable protein kinase C (PKC) betaII peptide inhibitor was used to test the hypothesis that PKC betaII inhibition could attenuate PMN-induced cardiac dysfunction by suppression of superoxide production from PMNs and increase NO release from vascular endothelium. The effects of the PKC betaII peptide inhibitor were examined in isolated ischemic (20 min) and reperfused (45 min) rat hearts with PMNs. The PKC betaII inhibitor (10 microM; n = 7) significantly attenuated PMN-induced cardiac dysfunction compared with I/R hearts (n = 9) receiving PMNs alone in left ventricular developed pressure (LVDP) and the maximal rate of LVDP (+dP/dt(max)) cardiac function indices (p < 0.01). The PKC betaII inhibitor at 10 microM significantly increased endothelial NO release from a basal value of 1.85 +/- 0.18 pmol NO/mg tissue to 3.49 +/- 0.62 pmol NO/mg tissue from rat aorta. It also significantly inhibited superoxide release (i.e., absorbance) from N-formyl-L-methionyl-L-leucyl-L-phenylalanine-stimulated rat PMNs from 0.13 +/- 0.01 to 0.02 +/- 0.004 (p < 0.01) at 10 microM. Histological analysis of the left ventricle of representative rat hearts from each group showed that the PKC betaII peptide inhibitor-treated hearts experienced a marked reduction in PMN vascular adherence and infiltration into the postreperfused cardiac tissue compared with I/R + PMN hearts (p < 0.01). These results suggest that the PKC betaII peptide inhibitor attenuates PMN-induced post-I/R cardiac contractile dysfunction by increasing endothelial NO release and by inhibiting superoxide release from PMNs. PMID:15878997

  18. Targeting Translation Control with p70 S6 Kinase 1 Inhibitors to Reverse Phenotypes in Fragile X Syndrome Mice.

    Science.gov (United States)

    Bhattacharya, Aditi; Mamcarz, Maggie; Mullins, Caitlin; Choudhury, Ayesha; Boyle, Robert G; Smith, Daniel G; Walker, David W; Klann, Eric

    2016-07-01

    Aberrant neuronal translation is implicated in the etiology of numerous brain disorders. Although mTORC1-p70 ribosomal S6 kinase 1 (S6K1) signaling is critical for translational control, pharmacological manipulation in vivo has targeted exclusively mTORC1 due to the paucity of specific inhibitors to S6K1. However, small molecule inhibitors of S6K1 could potentially ameliorate pathological phenotypes of diseases, which are based on aberrant translation and protein expression. One such condition is fragile X syndrome (FXS), which is considered to be caused by exaggerated neuronal translation and is the most frequent heritable cause of autism spectrum disorder (ASD). To date, potential therapeutic interventions in FXS have focused largely on targets upstream of translational control to normalize FXS-related phenotypes. Here we test the ability of two S6K1 inhibitors, PF-4708671 and FS-115, to normalize translational homeostasis and other phenotypes exhibited by FXS model mice. We found that although the pharmacokinetic profiles of the two S6K1 inhibitors differed, they overlapped in reversing multiple disease-associated phenotypes in FXS model mice including exaggerated protein synthesis, inappropriate social behavior, behavioral inflexibility, altered dendritic spine morphology, and macroorchidism. In contrast, the two inhibitors differed in their ability to rescue stereotypic marble-burying behavior and weight gain. These findings provide an initial pharmacological characterization of the impact of S6K1 inhibitors in vivo for FXS, and have therapeutic implications for other neuropsychiatric conditions involving aberrant mTORC1-S6K1 signaling. PMID:26708105

  19. Aplysia cell adhesion molecule and a novel protein kinase C activity in the postsynaptic neuron are required for presynaptic growth and initial formation of specific synapses

    OpenAIRE

    Hu, Jiang-Yuan; Chen, Yang; Bougie, Joanna K; Sossin, Wayne S.; Schacher, Samuel

    2010-01-01

    To explore the role of both Aplysia cell adhesion molecule (ApCAM) and activity of specific protein kinase C (PKC) isoforms in the initial formation of sensory neuron synapses with specific postsynaptic targets (L7 but not L11), we examined presynaptic growth, initial synapse formation, and the expression of the presynaptic neuropeptide sensorin following cell-specific reduction of ApCAM or of a novel PKC activity. Synapse formation between sensory neurons and L7 begins by 3 h after plating a...

  20. The role of phosphatidylinositol 3-kinase in neural cell adhesion molecule-mediated neuronal differentiation and survival

    DEFF Research Database (Denmark)

    Ditlevsen, Dorte K; Køhler, Lene B; Pedersen, Martin Volmer;

    2003-01-01

    kinase (MAPK) pathway and an increase in intracellular Ca2+ levels. Stimulation of neurones with the synthetic NCAM-ligand, C3, induces neurite outgrowth through signalling pathways similar to the pathways activated through physiological, homophilic NCAM-stimulation. We present here data indicating...... that phosphatidylinositol 3-kinase (PI3K) is required for NCAM-mediated neurite outgrowth from PC12-E2 cells and from cerebellar and dopaminergic neurones in primary culture, and that the thr/ser kinase Akt/protein kinase B (PKB) is phosphorylated downstream of PI3K after stimulation with C3. Moreover, we present data...

  1. Structural studies of nucleoside analog and feedback inhibitor binding to Drosophila melanogaster multisubstrate deoxyribonucleoside kinase

    DEFF Research Database (Denmark)

    Mikkelsen, Niels Egil; Munch-Petersen, Birgitte; Eklund, Hans

    2008-01-01

    relate them to the binding of substrate and feedback inhibitors. dCTP and dGTP binds similarly as the feedback inhibitor dTTP with the base in the substrate site. All investigated nucleoside analogs bind similarly as the pyrimidine substrates with many interactions in common. In contrast, the base of d...

  2. Resistance to mTOR kinase inhibitors in lymphoma cells lacking 4EBP1.

    Directory of Open Access Journals (Sweden)

    Sharmila Mallya

    Full Text Available Inhibitors of the mechanistic target of rapamycin (mTOR hold promise for treatment of hematological malignancies. Analogs of the allosteric mTOR inhibitor rapamycin are approved for mantle cell lymphoma but have limited efficacy in other blood cancers. ATP-competitive "active-site" mTOR inhibitors produce more complete mTOR inhibition and are more effective than rapamycin in preclinical models of leukemia, lymphoma and multiple myeloma. In parallel to clinical trials of active-site mTOR inhibitors, it will be important to identify resistance mechanisms that might limit drug efficacy in certain patients. From a panel of diffuse large B-cell lymphoma cell lines, we found that the VAL cell line is particularly resistant to apoptosis in the presence of active-site mTOR inhibitors. Mechanistic investigation showed that VAL does not express eukaryotic initiation factor 4E-binding protein-1 (4EBP1, a key negative regulator of translation controlled by mTOR. Although VAL cells express the related protein 4EBP2, mTOR inhibitor treatment fails to displace eukaryotic initiation factor 4G from the mRNA cap-binding complex. Knockdown of eukaryotic initiation factor 4E, or re-expression of 4EBP1, sensitizes cells to apoptosis when treated with active-site mTOR inhibitors. These findings provide a naturally occurring example of 4EBP deficiency driving lymphoma cell resistance to active-site mTOR inhibitors.

  3. A receptor tyrosine kinase inhibitor, Tyrphostin A9 induces cancer cell death through Drp1 dependent mitochondria fragmentation

    International Nuclear Information System (INIS)

    Highlights: → We screened and identified Tyrphostin A9, a receptor tyrosine kinase inhibitor as a strong mitochondria fission inducer. → Tyrphostin A9 treatment promotes mitochondria dysfunction and contributes to cytotoxicity in cancer cells. → Tyrphostin A9 induces apoptotic cell death through a Drp1-mediated pathway. → Our studies suggest that Tyrphostin A9 induces mitochondria fragmentation and apoptotic cell death via Drp1 dependently. -- Abstract: Mitochondria dynamics controls not only their morphology but also functions of mitochondria. Therefore, an imbalance of the dynamics eventually leads to mitochondria disruption and cell death. To identify specific regulators of mitochondria dynamics, we screened a bioactive chemical compound library and selected Tyrphostin A9, a tyrosine kinase inhibitor, as a potent inducer of mitochondrial fission. Tyrphostin A9 treatment resulted in the formation of fragmented mitochondria filament. In addition, cellular ATP level was decreased and the mitochondrial membrane potential was collapsed in Tyr A9-treated cells. Suppression of Drp1 activity by siRNA or over-expression of a dominant negative mutant of Drp1 inhibited both mitochondrial fragmentation and cell death induced by Tyrpohotin A9. Moreover, treatment of Tyrphostin A9 also evoked mitochondrial fragmentation in other cells including the neuroblastomas. Taken together, these results suggest that Tyrphostin A9 induces Drp1-mediated mitochondrial fission and apoptotic cell death.

  4. Data for proteomic analysis of ATP-binding proteins and kinase inhibitor target proteins using an ATP probe

    Directory of Open Access Journals (Sweden)

    Jun Adachi

    2015-12-01

    Full Text Available Interactions between ATP and ATP-binding proteins (ATPome are common and are required for most cellular processes. Thus, it is clearly important to identify and quantify these interactions for understanding basic cellular mechanisms and the pathogenesis of various diseases. We used an ATP competition assay (competition between ATP and acyl-ATP probes that enabled us to distinguish specific ATP-binding proteins from non-specific proteins (Adachi et al., 2014 [1]. As a result, we identified 539 proteins, including 178 novel ATP-binding protein candidates. We also established an ATPome selectivity profiling method for kinase inhibitors using our cataloged ATPome list. Normally only kinome selectivity is profiled in selectivity profiling of kinase inhibitors. In this data, we expand the profiled targets from the kinome to the ATPome through performance of ATPome selectivity profiling and obtained target profiles of staurosporine and (S-crizotinib. The data accompanying the manuscript on this approach (Adachi et al., 2014 [1] have been deposited to the ProteomeXchange with identifier PXD001200.

  5. Role of the p21 Cyclin-Dependent Kinase Inhibitor in Limiting Intimal Cell Proliferation in Response to Arterial Injury

    Science.gov (United States)

    Yang, Zhi-Yong; Simari, Robert D.; Perkins, Neil D.; San, Hong; Gordon, David; Nabel, Gary J.; Nabel, Elizabeth G.

    1996-07-01

    Arterial injury induces a series of proliferative, vasoactive, and inflammatory responses that lead to vascular proliferative diseases, including atherosclerosis and restenosis. Although several factors have been defined which stimulate this process in vivo, the role of specific cellular gene products in limiting this response is not well understood. The p21 cyclin-dependent kinase inhibitor affects cell cycle progression, senescence, and differentiation in transformed cells, but its expression in injured blood vessels has not been investigated. In this study, we report that p21 protein is induced in porcine arteries following balloon catheter injury and suggest that p21 is likely to play a role in limiting arterial cell proliferation in vivo. Vascular endothelial and smooth muscle cell growth was arrested through the ability of p21 to inhibit progression through the G1 phase of the cell cycle. Following injury to porcine arteries, p21 gene product was detected in the neointima and correlated inversely with the location and kinetics of intimal cell proliferation. Direct gene transfer of p21 using an adenoviral vector into balloon injured porcine arteries inhibited the development of intimal hyperplasia. Taken together, these findings suggest that p21, and possibly related cyclin-dependent kinase inhibitors, may normally regulate cellular proliferation following arterial injury, and strategies to increase its expression may prove therapeutically beneficial in vascular diseases.

  6. Novel hinge-binding motifs for Janus kinase 3 inhibitors: a comprehensive structure-activity relationship study on tofacitinib bioisosteres.

    Science.gov (United States)

    Gehringer, Matthias; Forster, Michael; Pfaffenrot, Ellen; Bauer, Silke M; Laufer, Stefan A

    2014-11-01

    The Janus kinases (JAKs) are a family of cytosolic tyrosine kinases crucially involved in cytokine signaling. JAKs have been demonstrated to be valid targets in the treatment of inflammatory and myeloproliferative disorders, and two inhibitors, tofacitinib and ruxolitinib, recently received their marketing authorization. Despite this success, selectivity within the JAK family remains a major issue. Both approved compounds share a common 7H-pyrrolo[2,3-d]pyrimidine hinge binding motif, and little is known about modifications tolerated at this heterocyclic core. In the current study, a library of tofacitinib bioisosteres was prepared and tested against JAK3. The compounds possessed the tofacitinib piperidinyl side chain, whereas the hinge binding motif was replaced by a variety of heterocycles mimicking its pharmacophore. In view of the promising expectations obtained from molecular modeling, most of the compounds proved to be poorly active. However, strategies for restoring activity within this series of novel chemotypes were discovered and crucial structure-activity relationships were deduced. The compounds presented may serve as starting point for developing novel JAK inhibitors and as a valuable training set for in silico models.

  7. Isomeric mono-, di-, and tri-bromobenzo-1H-triazoles as inhibitors of human protein kinase CK2α.

    Directory of Open Access Journals (Sweden)

    Romualda Wąsik

    Full Text Available To further clarify the role of the individual bromine atoms of 4,5,6,7-tetrabromotriazole (TBBt, a relatively selective inhibitor of protein kinase CK2, we have examined the inhibition (IC(50 of human CK2α by the two mono-, the four di-, and the two tri- bromobenzotriazoles relative to that of TBBt. Halogenation of the central vicinal C(5/C(6 atoms proved to be a key factor in enhancing inhibitory activity, in that 5,6-di-Br(2Bt and 4,5,6-Br(3Bt were almost as effective inhibitors as TBBt, notwithstanding their marked differences in pK(a for dissociation of the triazole proton. The decrease in pK(a on halogenation of the peripheral C(4/C(7 atoms virtually nullifies the gain due to hydrophobic interactions, and does not lead to a decrease in IC(50. Molecular modeling of structures of complexes of the ligands with the enzyme, as well as QSAR analysis, pointed to a balance of hydrophobic and electrostatic interactions as a discriminator of inhibitory activity. The role of halogen bonding remains debatable, as originally noted for the crystal structure of TBBt with CK2α (pdb1j91. Finally we direct attention to the promising applicability of our series of well-defined halogenated benzotriazoles to studies on inhibition of kinases other than CK2.

  8. Benzothiazole Derivative as a Novel Mycobacterium tuberculosis Shikimate Kinase Inhibitor: Identification and Elucidation of Its Allosteric Mode of Inhibition.

    Science.gov (United States)

    Mehra, Rukmankesh; Rajput, Vikrant Singh; Gupta, Monika; Chib, Reena; Kumar, Amit; Wazir, Priya; Khan, Inshad Ali; Nargotra, Amit

    2016-05-23

    Mycobacterium tuberculosis shikimate kinase (Mtb-SK) is a key enzyme involved in the biosynthesis of aromatic amino acids through the shikimate pathway. Since it is proven to be essential for the survival of the microbe and is absent from mammals, it is a promising target for anti-TB drug discovery. In this study, a combined approach of in silico similarity search and pharmacophore building using already reported inhibitors was used to screen a procured library of 20,000 compounds of the commercially available ChemBridge database. From the in silico screening, 15 hits were identified, and these hits were evaluated in vitro for Mtb-SK enzyme inhibition. Two compounds presented significant enzyme inhibition with IC50 values of 10.69 ± 0.9 and 46.22 ± 1.2 μM. The best hit was then evaluated for the in vitro mode of inhibition where it came out to be an uncompetitive and noncompetitive inhibitor with respect to shikimate (SKM) and ATP, respectively, suggesting its binding at an allosteric site. Potential binding sites of Mtb-SK were identified which confirmed the presence of an allosteric binding pocket apart from the ATP and SKM binding sites. The docking simulations were performed at this pocket in order to find the mode of binding of the best hit in the presence of substrates and the products of the enzymatic reaction. Molecular dynamics (MD) simulations elucidated the probability of inhibitor binding at the allosteric site in the presence of ADP and shikimate-3-phosphate (S-3-P), that is, after the formation of products of the reaction. The inhibitor binding may prevent the release of the product from Mtb-SK, thereby inhibiting its activity. The binding stability and the key residue interactions of the inhibitor to this product complex were also revealed by the MD simulations. Residues ARG43, ILE45, and PHE57 were identified as crucial that were involved in interactions with the best hit. This is the first report of an allosteric binding site of Mtb-SK, which

  9. Inhaled tyrosine kinase inhibitors for pulmonary hypertension: a possible future treatment

    Directory of Open Access Journals (Sweden)

    Pitsiou G

    2014-10-01

    Full Text Available Georgia Pitsiou,1 Paul Zarogoulidis,1 Dimitris Petridis,2 Ioannis Kioumis,1 Sofia Lampaki,1 John Organtzis,1 Konstantinos Porpodis,1 Antonis Papaiwannou,1 Theodora Tsiouda,3 Wolfgang Hohenforst-Schmidt,4 Stylianos Kakolyris,5 Konstantinos Syrigos,6 Haidong Huang,7 Qiang Li,7 J Francis Turner,8 Konstantinos Zarogoulidis1 1Pulmonary Department, G Papanikolaou General Hospital, Aristotle University of Thessaloniki, 2Department of Food Technology, School of Food Technology and Nutrition, Alexander Technological Educational Institute, 3Internal Medicine Department, Thegenio Anticancer Hospital, Thessaloniki, Greece; 4II Medical Department, Coburg Regional Hospital, Coburg, Germany; 5Oncology Department, Sotiria Hospital of Chest Diseases, University of Athens, Athens, 6Oncology Department, University General Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece; 7Department of Respiratory Diseases, Changhai Hospital/First Affiliated Hospital of the Second Military Medical University, Shanghai, People’s Republic of China; 8Division of Interventional Pulmonology and Medical Oncology, Cancer Treatment Centers of America, Western Regional Medical Center, Goodyear, AZ, USA Abstract: Pulmonary hypertension is a disease with severe consequences for the human body. There are several diseases and situations that induce pulmonary hypertension and are usually underdiagnosed. Treatments include conventional medical therapies and oral, inhaled, intravenous, and subcutaneous options. Depending on its severity, heart or lung transplant may also be an option. A possible novel treatment could be tyrosine kinase inhibitors. We conducted experiments with three jet nebulizers and three ultrasound nebulizers with erlotinib, gefitinib, and imatinib. Different residual cup designs and residual cup loadings were used in order to identify the best combination to produce droplets of less than 5 µm in mass median aerodynamic diameter. We

  10. Patients harboring EGFR mutation after primary resistance to crizotinib and response to EGFR-tyrosine kinase inhibitor

    Directory of Open Access Journals (Sweden)

    Wang WX

    2016-01-01

    Full Text Available Wenxian Wang,1 Xiaowen Jiang,1 Zhengbo Song,1,2 Yiping Zhang1,2 1Department of Chemotherapy, Zhejiang Cancer Hospital, 2Key Laboratory Diagnosis and Treatment Technology on Thoracic Oncology, Hangzhou, Zhejiang, People’s Republic of China Abstract: Anaplastic lymphoma kinase (ALK rearrangement lung cancer responds to ALK tyrosine kinase inhibitors. It is known that many cases ultimately acquired resistance to crizotinib. However, a case of primary resistance is rare. We present a case of harboring exon 19 deletion in epidermal growth factor receptor in ALK rearranged lung adenocarcinoma, who experienced a partial tumor response to icotinib after failure with crizotinib therapy and chemotherapy. Considering the partial response, we conclude that it is important to find the cause of resistance to crizotinib. We detected gene mutations with plasma by the next-generation sequencing; the next-generation sequencing demonstrates an attractive system to identify mutations improving the outcome of patients with a deadly disease. Keywords: non-small cell lung cancer, anaplastic lymphoma kinase, crizotinib, epidermal growth factor receptor

  11. Os inibidores de tirosino quinase de segunda geração The inhibitors of tyrosine kinase

    Directory of Open Access Journals (Sweden)

    Márcia T. Delamain

    2008-04-01

    Full Text Available O imatinibe tem sido confirmado como terapia de primeira linha para a Leucemia Mielóide Crônica (LMC por apresentar respostas duradouras na maior parte dos pacientes, principalmente nos que se encontram em fase precoce da doença. Entretanto, resistência ou intolerância ao imatinibe podem ocorrer. A resistência ao imatinibe ocorre com muito mais freqüência em fases mais avançadas da doença, sendo a causa mais comum o desenvolvimento de mutações no sítio BCR-ABL. Em face deste problema, novos inibidores de tirosino quinase têm sido desenvolvidos, com maior potência, diminuindo assim a chance de desenvolvimento de resistência ao tratamento. O nilotinibe e o dasatinibe são dois exemplos de inibidores de segunda geração de tirosino quinase recentemente aprovados. Ambos têm demonstrado excelentes resultados em pacientes que desenvolvem resistência ou são intolerantes ao imatinibe.Despite the success with imatinib as the first choice treatment of chronic myeloid leukemia (CML, there is still a subset of patients that do not respond optimally to or are intolerant of this drug or lose response. Imatinib resistance can occur at any phase, but it is more frequent in advanced phases, with mutations in the BCR-ABL kinase domain being the most common mechanism of resistance. More potent tyrosine kinase inhibitors have been developed that can overcome resistance to imatinib. Nilotinib and dasatinib are good examples of new tyrosine kinase inhibitors that are available. With these new agents, patients who develop imatinib resistance or those unable to tolerate imatinib treatment can achieve significant clinical responses.

  12. The direct effect of Focal Adhesion Kinase (FAK), dominant-negative FAK, FAK-CD and FAK siRNA on gene expression and human MCF-7 breast cancer cell tumorigenesis

    International Nuclear Information System (INIS)

    Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in survival signaling. FAK has been shown to be overexpressed in breast cancer tumors at early stages of tumorigenesis. To study the direct effect of FAK on breast tumorigenesis, we developed Tet-ON (tetracycline-inducible) system of MCF-7 breast cancer cells stably transfected with FAK or dominant-negative, C-terminal domain of FAK (FAK-CD), and also FAKsiRNA with silenced FAK MCF-7 stable cell line. Increased expression of FAK in isogenic Tet-inducible MCF-7 cells caused increased cell growth, adhesion and soft agar colony formation in vitro, while expression of dominant-negative FAK inhibitor caused inhibition of these cellular processes. To study the role of induced FAK and FAK-CD in vivo, we inoculated these Tet-inducible cells in nude mice to generate tumors in the presence or absence of doxycycline in the drinking water. FAKsiRNA-MCF-7 cells were also injected into nude mice to generate xenograft tumors. Induction of FAK resulted in significant increased tumorigenesis, while induced FAK-CD resulted in decreased tumorigenesis. Taq Man Low Density Array assay demonstrated specific induction of FAKmRNA in MCF-7-Tet-ON-FAK cells. DMP1, encoding cyclin D binding myb-like protein 1 was one of the genes specifically affected by Tet-inducible FAK or FAK-CD in breast xenograft tumors. In addition, silencing of FAK in MCF-7 cells with FAK siRNA caused increased cell rounding, decreased cell viability in vitro and inhibited tumorigenesis in vivo. Importantly, Affymetrix microarray gene profiling analysis using Human Genome U133A GeneChips revealed >4300 genes, known to be involved in apoptosis, cell cycle, and adhesion that were significantly down- or up-regulated (p < 0.05) by FAKsiRNA. Thus, these data for the first time demonstrate the direct effect of FAK expression and function on MCF-7 breast cancer tumorigenesis in vivo and reveal specific expression of genes affected by

  13. The direct effect of Focal Adhesion Kinase (FAK, dominant-negative FAK, FAK-CD and FAK siRNA on gene expression and human MCF-7 breast cancer cell tumorigenesis

    Directory of Open Access Journals (Sweden)

    Zhang Li

    2009-08-01

    Full Text Available Abstract Background Focal adhesion kinase (FAK is a non-receptor tyrosine kinase that plays an important role in survival signaling. FAK has been shown to be overexpressed in breast cancer tumors at early stages of tumorigenesis. Methods To study the direct effect of FAK on breast tumorigenesis, we developed Tet-ON (tetracycline-inducible system of MCF-7 breast cancer cells stably transfected with FAK or dominant-negative, C-terminal domain of FAK (FAK-CD, and also FAKsiRNA with silenced FAK MCF-7 stable cell line. Increased expression of FAK in isogenic Tet-inducible MCF-7 cells caused increased cell growth, adhesion and soft agar colony formation in vitro, while expression of dominant-negative FAK inhibitor caused inhibition of these cellular processes. To study the role of induced FAK and FAK-CD in vivo, we inoculated these Tet-inducible cells in nude mice to generate tumors in the presence or absence of doxycycline in the drinking water. FAKsiRNA-MCF-7 cells were also injected into nude mice to generate xenograft tumors. Results Induction of FAK resulted in significant increased tumorigenesis, while induced FAK-CD resulted in decreased tumorigenesis. Taq Man Low Density Array assay demonstrated specific induction of FAKmRNA in MCF-7-Tet-ON-FAK cells. DMP1, encoding cyclin D binding myb-like protein 1 was one of the genes specifically affected by Tet-inducible FAK or FAK-CD in breast xenograft tumors. In addition, silencing of FAK in MCF-7 cells with FAK siRNA caused increased cell rounding, decreased cell viability in vitro and inhibited tumorigenesis in vivo. Importantly, Affymetrix microarray gene profiling analysis using Human Genome U133A GeneChips revealed >4300 genes, known to be involved in apoptosis, cell cycle, and adhesion that were significantly down- or up-regulated (p Conclusion Thus, these data for the first time demonstrate the direct effect of FAK expression and function on MCF-7 breast cancer tumorigenesis in vivo and reveal

  14. Synthesis and biological evaluation of novel substituted pyrrolo[1,2-a]quinoxaline derivatives as inhibitors of the human protein kinase CK2.

    Science.gov (United States)

    Guillon, Jean; Le Borgne, Marc; Rimbault, Charlotte; Moreau, Stéphane; Savrimoutou, Solène; Pinaud, Noël; Baratin, Sophie; Marchivie, Mathieu; Roche, Séverine; Bollacke, Andre; Pecci, Adali; Alvarez, Lautaro; Desplat, Vanessa; Jose, Joachim

    2013-07-01

    Herein we describe the synthesis and properties of substituted phenylaminopyrrolo[1,2-a]quinoxaline-carboxylic acid derivatives as a novel class of potent inhibitors of the human protein kinase CK2. A set of 15 compounds was designed and synthesized using convenient and straightforward synthesis protocols. The compounds were tested for inhibition of human protein kinase CK2, which is a potential drug target for many diseases including inflammatory disorders and cancer. New inhibitors with IC50 in the micro- and sub-micromolar range were identified. The most promising compound, the 4-[(3-chlorophenyl)amino]pyrrolo[1,2-a]quinoxaline-3-carboxylic acid 1c inhibited human CK2 with an IC50 of 49 nM. Our findings indicate that pyrrolo[1,2-a]quinoxalines are a promising starting scaffold for further development and optimization of human protein kinase CK2 inhibitors.

  15. Comparative evaluation of bone marrow cells morpho-functional activity in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors of the first and second generation

    Directory of Open Access Journals (Sweden)

    I. O. Zhaleyko

    2014-07-01

    Full Text Available The efficiency of using the culture techniques of research for monitoring the patient’s response to the treatment by tyrosine kinase inhibitors of the first and second generation is shown. Thus, the functional activity of bone marrow cells in patients having the optimal treatment response to inhibitors of tyrosine kinases was significantly lower compared with patients with the acquired resistance to the drug, and patients who had CML diagnosed for first time. Furthermore, for patients with the optimal response to the nilotinib therapy, numbers of colonies in semi-solid agar in vitro was lower, than in patients with the optimal response to imatinib. When the leukaemic cell clone becomes resistant to tyrosine kinase inhibitors, the prevalence of early cells of granulocyte-macrophage hematopoietic stem cells is observed in CFU culture which can be an important prognostic factor for choosing the appropriate treatment strategy.

  16. Roles of phosphatidylinositol 3-kinase and NF-kappaB in human cytomegalovirus-mediated monocyte diapedesis and adhesion: strategy for viral persistence.

    Science.gov (United States)

    Smith, M Shane; Bivins-Smith, Elizabeth R; Tilley, A Michael; Bentz, Gretchen L; Chan, Gary; Minard, Jessica; Yurochko, Andrew D

    2007-07-01

    Infected peripheral blood monocytes are proposed to play a key role in the hematogenous dissemination of human cytomegalovirus (HCMV) to tissues, a critical step in the establishment of HCMV persistence and the development of HCMV-associated diseases. We recently provided evidence for a unique strategy involved in viral dissemination: HCMV infection of primary human monocytes promotes their transendothelial migration and differentiation into proinflammatory macrophages permissive for the replication of the original input virus. To decipher the mechanism of hematogenous spread, we focused on the viral dysregulation of early cellular processes involved in transendothelial migration. Here, we present evidence that both phosphatidylinositol 3-kinase [PI(3)K] and NF-kappaB activities were crucial for the HCMV induction of monocyte motility and firm adhesion to endothelial cells. We found that the beta(1) integrins, the beta(2) integrins, intracellular adhesion molecule 1 (ICAM-1), and ICAM-3 were upregulated following HCMV infection and that they played a key role in the firm adhesion of infected monocytes to the endothelium. The viral regulation of adhesion molecule expression is complex, with PI(3)K and NF-kappaB affecting the expression of each adhesion molecule at different stages of the expression cascade. Our data demonstrate key roles for PI(3)K and NF-kappaB signaling in the HCMV-induced cellular changes in monocytes and identify the biological rationale for the activation of these pathways in infected monocytes, which together suggest a mechanism for how HCMV promotes viral spread to and persistence within host organs.

  17. Induction of apoptosis in cancer cells by tumor necrosis factor and butyrolactone, an inhibitor of cyclin-dependent kinases

    Directory of Open Access Journals (Sweden)

    Belizário J.E.

    1999-01-01

    Full Text Available Induction of apoptosis by tumor necrosis factor (TNF is modulated by changes in the expression and activity of several cell cycle regulatory proteins. We examined the effects of TNF (1-100 ng/ml and butyrolactone I (100 µM, a specific inhibitor of cyclin-dependent kinases (CDK with high selectivity for CDK-1 and CDK-2, on three different cancer cell lines: WEHI, L929 and HeLa S3. Both compounds blocked cell growth, but only TNF induced the common events of apoptosis, i.e., chromatin condensation and ladder pattern of DNA fragmentation in these cell lines. The TNF-induced apoptosis events were increased in the presence of butyrolactone. In vitro phosphorylation assays for exogenous histone H1 and endogenous retinoblastoma protein (pRb in the total cell lysates showed that treatment with both TNF and butyrolactone inhibited the histone H1 kinase (WEHI, L929 and HeLa and pRb kinase (WEHI activities of CDKs, as compared with the controls. The role of proteases in the TNF and butyrolactone-induced apoptosis was evaluated by comparing the number and expression of polypeptides in the cell lysates by gel electrophoresis. TNF and butyrolactone treatment caused the disappearance of several cellular protein bands in the region between 40-200 kDa, and the 110- 90- and 50-kDa proteins were identified as the major substrates, whose degradation was remarkably increased by the treatments. Interestingly, the loss of several cellular protein bands was associated with the marked accumulation of two proteins apparently of 60 and 70 kDa, which may be cleavage products of one or more proteins. These findings link the decrease of cyclin-dependent kinase activities to the increase of protease activities within the growth arrest and apoptosis pathways induced by TNF.

  18. ZD6474, an inhibitor of VEGFR and EGFR tyrosine kinase activity in combination with radiotherapy

    International Nuclear Information System (INIS)

    Radiation enhances both epithelial growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) expression, which are a part of key pathways for tumor progression. Some tumors may not respond well to EGFR inhibitors alone or may develop resistance to EGFR inhibitors. Therefore, drug therapy targeted to VEGF receptors and EGFRs, when combined with radiotherapy (RT), may improve tumor control and provide wider applicability. This article focuses on ZD6474, an inhibitor of EGFR and VEGF receptor signaling in combination with RT. We discuss preclinical and clinical studies with RT and inhibitors of VEGF or EGFR signaling first. We then address issues associated with ZD6474 pharmacokinetic dosing, and scheduling when combined with RT. We also discuss ZD6474 in the context of anti-EGFR therapy resistance. Dual inhibition of EGFR and VEGF receptor signaling pathways shows promise in enhancing RT efficacy

  19. Design and synthesis of an in vivo-efficacious PIM3 kinase inhibitor as a candidate anti-pancreatic cancer agent.

    Science.gov (United States)

    Nakano, Hirofumi; Hasegawa, Tsukasa; Saito, Nae; Furukawa, Kaoru; Mukaida, Naofumi; Kojima, Hirotatsu; Okabe, Takayoshi; Nagano, Tetsuo

    2015-12-15

    Serine/threonine kinase PIM3 is a potential therapeutic target for pancreatic cancer. Here, we describe the evolution of our previous PIM1 inhibitor 1 into PIM3 inhibitor 11 guided by use of the crystal structure of PIM1 as a surrogate to provide a basis for rational modification. Compound 11 potently inhibits PIM3 kinase activity, as well as growth of several pancreatic cancer cell lines. In a mouse xenograft model, 11 inhibited growth of human pancreatic cancer cell line PCI66 with negligible body weight loss. Thus, 11 appears to be a promising lead compound for further optimization to develop new anti-pancreatic cancer agents. PMID:26547690

  20. P38 MAP kinase inhibitors as potential therapeutics for the treatment of joint degeneration and pain associated with osteoarthritis

    Directory of Open Access Journals (Sweden)

    Taiwo Yetunde O

    2008-12-01

    Full Text Available Abstract Background Evaluate the potential role of p38 inhibitors for the treatment of osteoarthritis using an animal model of joint degeneration (iodoacetate-induced arthritis and a pain model (Hargraeves assay. Methods P38 kinase activity was evaluated in a kinase assay by measuring the amount of phosphorylated substrate ATF2 using a phosphoATF2 (Thr71 specific primary antibody and an alkaline phosphate coupled secondary antibody and measuring the OD at 405 nm. TNFα and IL-1β secretion from LPS stimulated THP-1 monocytic cells and human peripheral blood mononuclear cells were measured by ELISA. Rats treated with vehicle or p38 inhibitor were injected intra-articularly in one knee with iodoacetate and damage to the tibial plateau was assessed from digitized images captured using an image analyzer. The effect of p38 inhibitors on hyperalgesia was evaluated in rats given an intraplantar injection of carrageenan and 4 h later the paw withdrawal time to a radiant heat source was measured. Results SB-203580 and VX-745 are both potent inhibitors of p38 with IC50s of 136 ± 64 nM and 35 ± 14 nM (mean ± S.D., respectively. Similarly, SB-203580 and VX-745 potently inhibited TNF release from LPS stimulated human THP-1 cells with IC50s of 72 ± 15 nM; and 29 ± 14 nM (mean ± S.D. respectively. TNF release from LPS stimulated human peripheral blood mononuclear cells was inhibited with IC50s 16 ± 6 nM and 14 ± 8 nM, (mean ± S.D. for SB-203580 and VX-745 and IL-1 was inhibited with IC50s of 20 ± 8 nM and 15 ± 4 nM (mean ± S.D., respectively. SB-203580 and VX-745 administered orally at a dose of 50 mg/kg resulted in the significant (p Conclusion SB203580 and VX-745 demonstrated attenuation of both cartilage degeneration and pain in animal models and suggest that p38 inhibitors may be a useful approach for the treatment of osteoarthritis.

  1. Mapping the residues of protein kinase CK2 alpha subunit responsible for responsiveness to polyanionic inhibitors

    DEFF Research Database (Denmark)

    Vaglio, P; Sarno, S; Marin, O;

    1996-01-01

    The quadruple mutation of the whole basic cluster, K74KKK77 conserved in the catalytic subunits of protein kinase CK2 and implicated in substrate recognition, not only abolishes inhibition by heparin but even induces with some peptide substrates an up to 5-fold stimulation by heparin in the 0...

  2. Expression of a TGF-{beta} regulated cyclin-dependent kinase inhibitor in normal and immortalized airway epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Tierney, L.A.; Bloomfield, C.; Johnson, N.F. [and others

    1995-12-01

    Tumors arising from epithelial cells, including lung cancers are frequently resistant to factors that regulate growth and differentiation in normal in normal cells. Once such factor is transforming growth factor-{Beta} (TGF-{Beta}). Escape from the growth-inhibitory effects of TGF-{Beta} is thought to be a key step in the transformation of airway epithelial cells. most lung cancer cell lines require serum for growth. In contrast, normal human bronchial epithelial (NHBE) cells are exquisitely sensitive to growth-inhibitory and differentiating effects of TGF-{Beta}. The recent identification of a novel cyclin-dependent kinase inhibitor, p15{sup INK4B}, which is regulated by TGF-{Beta}, suggests a mechanism by which TGF-{Beta} mediates growth arrest in NHBE cells. The purpose of this study was two-fold: (1) to determine if p15{sup INK4B} is induced by TGF-{Beta} in NHBE cells or immortalized bronchial epithelial (R.1) cells and if that induction corresponds to a G1/S cell-cycle arrest; (2) to determine the temporal relationship between p15{sup INK4B} induction, cell-cycle arrest, and the phosphorylation state of the pRB because it is thought that p15{sup INK4B} acts indirectly by preventing phosphorylation of the RB gene product. In this study, expression of p15{sup INK4B} was examined in NHBE cells and R.1 cells at different time intervals following TGF-{Beta} treatment. The expression of this kinase inhibitor and its relationship to the cell and the pRb phosphorylation state were examined in cells that were both sensitive (NHBE) and resistant (R.1) to the effects of TGF-{Beta}. These results suggest that the cyclin-dependent kinase inhibitor, p15{sup INK4B}, is involved in airway epithelial cell differentiation and that loss or reduction of expression plays a role in the resistance of transformed or neoplastic cells to the growth-inhibitory effects of TGF-{Beta}.

  3. Response to epidermal growth factor receptor inhibitors in non-small cell lung cancer cells : Limited antiproliferative effects and absence of apoptosis associated with persistent activity of extracellular signal-regulated kinase or Akt kinase pathways

    NARCIS (Netherlands)

    Janmaat, ML; Kruyt, FAE; Rodriguez, JA; Giaccone, G

    2003-01-01

    The epidermal growth factor receptor (EGFR) is an important novel target for anticancer therapy. In this study, we examined the molecular mechanisms that underlie the antitumor effects of the anti-EGFR monoclonal antibody C225 (Cetuximab) and the selective EGFR tyrosine kinase inhibitor ZD1839 (Ires

  4. Cooperation between c-Met and focal adhesion kinase family members in medulloblastoma and implications for therapy

    OpenAIRE

    Guessous, Fadila; Yang, Yanzhi; Johnson, Elizabeth; Marcinkiewicz, Lukasz; Smith, Matthew; Zhang, Ying; Kofman, Alexander; Schiff, David; Christensen, James; Abounader, Roger

    2011-01-01

    We previously demonstrated the involvement of the tyrosine kinase receptor c-Met in medulloblastoma malignancy. The nonreceptor tyrosine kinases FAK and Pyk2, are key players in the progression of different cancers. However, their role in medulloblastoma malignancy is not well understood. In this study, using a protein array approach, we found that c-Met phosphorylates FAK and Pyk2 in medulloblastoma cells. We therefore studied the interactions between c-Met and FAK/Pyk2 and their implication...

  5. Structure Guided Optimization, in Vitro Activity, and in Vivo Activity of Pan-PIM Kinase Inhibitors.

    Science.gov (United States)

    Burger, Matthew T; Han, Wooseok; Lan, Jiong; Nishiguchi, Gisele; Bellamacina, Cornelia; Lindval, Mika; Atallah, Gordana; Ding, Yu; Mathur, Michelle; McBride, Chris; Beans, Elizabeth L; Muller, Kristine; Tamez, Victoriano; Zhang, Yanchen; Huh, Kay; Feucht, Paul; Zavorotinskaya, Tatiana; Dai, Yumin; Holash, Jocelyn; Castillo, Joseph; Langowski, John; Wang, Yingyun; Chen, Min Y; Garcia, Pablo D

    2013-12-12

    Proviral insertion of Moloney virus (PIM) 1, 2, and 3 kinases are serine/threonine kinases that normally function in survival and proliferation of hematopoietic cells. As high expression of PIM1, 2, and 3 is frequently observed in many human malignancies, including multiple myeloma, non-Hodgkins lymphoma, and myeloid leukemias, there is interest in determining whether selective PIM inhibition can improve outcomes of these human cancers. Herein, we describe our efforts toward this goal. The structure guided optimization of a singleton high throughput screening hit in which the potency against all three PIM isoforms was increased >10,000-fold to yield compounds with pan PIM K is < 10 pM, nanomolar cellular potency, and in vivo activity in an acute myeloid leukemia Pim-dependent tumor model is described. PMID:24900629

  6. Glycogen Synthase Kinase 3 Inhibitors in the Next Horizon for Alzheimer's Disease Treatment

    Directory of Open Access Journals (Sweden)

    Ana Martinez

    2011-01-01

    Full Text Available Glycogen synthase kinase 3 (GSK-3, a proline/serine protein kinase ubiquitously expressed and involved in many cellular signaling pathways, plays a key role in the pathogenesis of Alzheimer's disease (AD being probably the link between β-amyloid and tau pathology. A great effort has recently been done in the discovery and development of different new molecules, of synthetic and natural origin, able to inhibit this enzyme, and several kinetics mechanisms of binding have been described. The small molecule called tideglusib belonging to the thiadiazolidindione family is currently on phase IIb clinical trials for AD. The potential risks and benefits of this new kind of disease modifying drugs for the future therapy of AD are discussed in this paper.

  7. SGX523 is an exquisitely selective, ATP-competitive inhibitor of the MET receptor tyrosine kinase with antitumor activity in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, Sean G.; Hendle, Jorg; Lee, Patrick S.; Smith, Christopher R.; Bounaud, Pierre-Yves; Jessen, Katti A.; Tang, Crystal M.; Huser, Nanni H.; Felce, Jeremy D.; Froning, Karen J.; Peterman, Marshall C.; Aubol, Brandon E.; Gessert, Steve F.; Sauder, J. Michael; Schwinn, Kenneth D.; Russell, Marijane; Rooney, Isabelle A.; Adams, Jason; Leon, Barbara C.; Do, Tuan H.; Blaney, Jeff M.; Sprengeler, Paul A.; Thompson, Devon A.; Smyth, Lydia; Pelletier, Laura A.; Atwell, Shane; Holme, Kevin; Wasserman, Stephen R.; Emtage, Spencer; Burley, Stephen K.; Reich, Siegfried H.; (Ventana); (SGX); (Genentech); (Amira)

    2010-01-12

    The MET receptor tyrosine kinase has emerged as an important target for the development of novel cancer therapeutics. Activation of MET by mutation or gene amplification has been linked to kidney, gastric, and lung cancers. In other cancers, such as glioblastoma, autocrine activation of MET has been demonstrated. Several classes of ATP-competitive inhibitor have been described, which inhibit MET but also other kinases. Here, we describe SGX523, a novel, ATP-competitive kinase inhibitor remarkable for its exquisite selectivity for MET. SGX523 potently inhibited MET with an IC{sub 50} of 4 nmol/L and is >1,000-fold selective versus the >200-fold selectivity of other protein kinases tested in biochemical assays. Crystallographic study revealed that SGX523 stabilizes MET in a unique inactive conformation that is inaccessible to other protein kinases, suggesting an explanation for the selectivity. SGX523 inhibited MET-mediated signaling, cell proliferation, and cell migration at nanomolar concentrations but had no effect on signaling dependent on other protein kinases, including the closely related RON, even at micromolar concentrations. SGX523 inhibition of MET in vivo was associated with the dose-dependent inhibition of growth of tumor xenografts derived from human glioblastoma and lung and gastric cancers, confirming the dependence of these tumors on MET catalytic activity. Our results show that SGX523 is the most selective inhibitor of MET catalytic activity described to date and is thus a useful tool to investigate the role of MET kinase in cancer without the confounding effects of promiscuous protein kinase inhibition.

  8. Molecular Pathways: Molecular Basis for Sensitivity and Resistance to JAK Kinase Inhibitors

    OpenAIRE

    Meyer, Sara C.; Levine, Ross L.

    2014-01-01

    Janus kinases (JAK) are the mediators of a variety of cytokine signals via their cognate receptors that result in activation of intracellular signaling pathways. Alterations in JAK1, JAK2, JAK3 and TYK2 signaling contribute to different disease states, and dysregulated JAK-STAT signaling is associated with hematological malignancies, autoimmune disorders and immune-deficient conditions. Genetic alterations of JAK2 occur in the majority of patients with myeloproliferative neoplasms (MPN) and o...

  9. Dermatologic Toxicities from Monoclonal Antibodies and Tyrosine Kinase Inhibitors against EGFR: Pathophysiology and Management

    OpenAIRE

    Shaad E. Abdullah; Missak Haigentz; Bilal Piperdi

    2012-01-01

    Epidermal growth factor receptor (EGFR) inhibition has now been well established as an effective treatment for various cancers. The EGFR belongs to the ErbB family of tyrosine kinase receptors which regulate tumor cell differentiation, survival and proliferation. Activation of EGFR drives tumorigenesis in lung, head and neck, colorectal and pancreatic cancers. Irrespective of the type of cancer being treated and the mechanism by which tumor EGFR drives tumorigenesis, the major side effect of ...

  10. Bruton's tyrosine kinase (Btk) inhibitor ibrutinib suppresses stem-like traits in ovarian cancer

    OpenAIRE

    Zucha, Muhammad Ary; Wu, Alexander T. H.; Lee, Wei-Hwa; Wang, Liang-Shun; Lin, Wan-Wan; Yuan, Chiou-Chung; Yeh, Chi-Tai

    2015-01-01

    According to a Prognoscan database, upregulation of Bruton's tyrosine kinase (Btk) is associated with low overall survival in ovarian cancer patients. We found that spheroids-forming ovarian cancer cell, which highly expressed cancer stem-like cell (CSC) markers and Btk, were cisplatin resistant. We next treated CSCs and non-CSCs by a combination of ibrutinib and cisplatin. We found that chemoresistance was dependent on Btk and JAK2/STAT3, which maintained CSC by inducing Sox-2 and prosurviva...

  11. PTEN and PI-3 kinase inhibitors control LPS signaling and the lymphoproliferative response in the CD19+ B cell compartment

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Alok R. [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Peirce, Susan K. [Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (United States); Joshi, Shweta [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Durden, Donald L., E-mail: ddurden@ucsd.edu [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Division of Pediatric Hematology-Oncology, UCSD Rady Children' s Hospital, La Jolla, CA (United States)

    2014-09-10

    -3 kinase inhibitors reverse the lymphoproliferative phenotype in vivo. - Highlights: • First genetic evidence that PTEN controls LPS/TLR4 signaling in B lymphocytes. • Evidence that PTEN regulates LPS induced lymphoproliferation in vivo. • PI-3 kinase inhibitors block LPS induced lymphoproliferation in vivo.

  12. The cAMP-dependent protein kinase inhibitor H-89 attenuates the bioluminescence signal produced by Renilla Luciferase.

    Directory of Open Access Journals (Sweden)

    Katie J Herbst

    Full Text Available BACKGROUND: Investigations into the regulation and functional roles of kinases such as cAMP-dependent protein kinase (PKA increasingly rely on cellular assays. Currently, there are a number of bioluminescence-based assays, for example reporter gene assays, that allow the study of the regulation, activity, and functional effects of PKA in the cellular context. Additionally there are continuing efforts to engineer improved biosensors that are capable of detecting real-time PKA signaling dynamics in cells. These cell-based assays are often utilized to test the involvement of PKA-dependent processes by using H-89, a reversible competitive inhibitor of PKA. PRINCIPAL FINDINGS: We present here data to show that H-89, in addition to being a competitive PKA inhibitor, attenuates the bioluminescence signal produced by Renilla luciferase (RLuc variants in a population of cells and also in single cells. Using 10 microM of luciferase substrate and 10 microM H-89, we observed that the signal from RLuc and RLuc8, an eight-point mutation variant of RLuc, in cells was reduced to 50% (+/-15% and 54% (+/-14% of controls exposed to the vehicle alone, respectively. In vitro, we showed that H-89 decreased the RLuc8 bioluminescence signal but did not compete with coelenterazine-h for the RLuc8 active site, and also did not affect the activity of Firefly luciferase. By contrast, another competitive inhibitor of PKA, KT5720, did not affect the activity of RLuc8. SIGNIFICANCE: The identification and characterization of the adverse effect of H-89 on RLuc signal will help deconvolute data previously generated from RLuc-based assays looking at the functional effects of PKA signaling. In addition, for the current application and future development of bioluminscence assays, KT5720 is identified as a more suitable PKA inhibitor to be used in conjunction with RLuc-based assays. These principal findings also provide an important lesson to fully consider all of the potential

  13. PTEN and PI-3 kinase inhibitors control LPS signaling and the lymphoproliferative response in the CD19+ B cell compartment

    International Nuclear Information System (INIS)

    kinase inhibitors reverse the lymphoproliferative phenotype in vivo. - Highlights: • First genetic evidence that PTEN controls LPS/TLR4 signaling in B lymphocytes. • Evidence that PTEN regulates LPS induced lymphoproliferation in vivo. • PI-3 kinase inhibitors block LPS induced lymphoproliferation in vivo

  14. Pyridoxal 5'-phosphate is a slow tight binding inhibitor of E. coli pyridoxal kinase.

    Directory of Open Access Journals (Sweden)

    Mohini S Ghatge

    Full Text Available Pyridoxal 5'-phosphate (PLP is a cofactor for dozens of B(6 requiring enzymes. PLP reacts with apo-B(6 enzymes by forming an aldimine linkage with the ε-amino group of an active site lysine residue, thus yielding the catalytically active holo-B(6 enzyme. During protein turnover, the PLP is salvaged by first converting it to pyridoxal by a phosphatase and then back to PLP by pyridoxal kinase. Nonetheless, PLP poses a potential toxicity problem for the cell since its reactive 4'-aldehyde moiety forms covalent adducts with other compounds and non-B(6 proteins containing thiol or amino groups. The regulation of PLP homeostasis in the cell is thus an important, yet unresolved issue. In this report, using site-directed mutagenesis, kinetic, spectroscopic and chromatographic studies we show that pyridoxal kinase from E. coli forms a complex with the product PLP to form an inactive enzyme complex. Evidence is presented that, in the inhibited complex, PLP has formed an aldimine bond with an active site lysine residue during catalytic turnover. The rate of dissociation of PLP from the complex is very slow, being only partially released after a 2-hour incubation with PLP phosphatase. Interestingly, the inactive pyridoxal kinase•PLP complex can be partially reactivated by transferring the tightly bound PLP to an apo-B(6 enzyme. These results open new perspectives on the mechanism of regulation and role of pyridoxal kinase in the Escherichia coli cell.

  15. Expression of the Apoptosis Inhibitor Survivin and its correlation with Thymidine Kinase and Axillary Lymph Node Metastasis in Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    Jian-Ping WU; Yun-Feng ZHOU; Zhi-Guo LUO; Ming-Sheng ZHANG

    2005-01-01

    @@ 1 Introduction Many molecular factors have been demonstrated to interfere with cellular proliferation and programmed cell death. One of these factors is a recently discovered member of the "inhibitor of apoptosis protein(IAP)" called survivin. Survivin is abundantly expressed in most solid and hematologic malignancies, but undetectable in normal adult tissues. Interference with survivin function induces pleiotropic cell-division defects and apoptosis. Cytosolic thymidine kinase (TK) is a marker for proliferating cells and TK is one of several key enzymes involved in DNAmetabolism that phosphorylates thymidine to thymidine mono-phosphate. This study was aimed to detect the expression of suvivin and TK in breast cancer, and to explore a possible relationship between survivin expression and axillary lymph node metastasis.

  16. Structure of the sporulation histidine kinase inhibitor Sda from Bacillus subtilis and insights into its solution state

    Energy Technology Data Exchange (ETDEWEB)

    Jacques, David A.; Streamer, Margaret; Rowland, Susan L.; King, Glenn F.; Guss, J. Mitchell; Trewhella, J.; Langley, David B.; (Sydney); (Queensland)

    2009-09-02

    The crystal structure of the DNA-damage checkpoint inhibitor of sporulation, Sda, from Bacillus subtilis, has been solved by the MAD technique using selenomethionine-substituted protein. The structure closely resembles that previously solved by NMR, as well as the structure of a homologue from Geobacillus stearothermophilus solved in complex with the histidine kinase KinB. The structure contains three molecules in the asymmetric unit. The unusual trimeric arrangement, which lacks simple internal symmetry, appears to be preserved in solution based on an essentially ideal fit to previously acquired scattering data for Sda in solution. This interpretation contradicts previous findings that Sda was monomeric or dimeric in solution. This study demonstrates the difficulties that can be associated with the characterization of small proteins and the value of combining multiple biophysical techniques. It also emphasizes the importance of understanding the physical principles behind these techniques and therefore their limitations.

  17. Repositioning of Tyrosine Kinase Inhibitors as Antagonists of ATP-Binding Cassette Transporters in Anticancer Drug Resistance

    Directory of Open Access Journals (Sweden)

    Yi-Jun Wang

    2014-09-01

    Full Text Available The phenomenon of multidrug resistance (MDR has attenuated the efficacy of anticancer drugs and the possibility of successful cancer chemotherapy. ATP-binding cassette (ABC transporters play an essential role in mediating MDR in cancer cells by increasing efflux of drugs from cancer cells, hence reducing the intracellular accumulation of chemotherapeutic drugs. Interestingly, small-molecule tyrosine kinase inhibitors (TKIs, such as AST1306, lapatinib, linsitinib, masitinib, motesanib, nilotinib, telatinib and WHI-P154, have been found to have the capability to overcome anticancer drug resistance by inhibiting ABC transporters in recent years. This review will focus on some of the latest and clinical developments with ABC transporters, TKIs and anticancer drug resistance.

  18. Synthesis of benzimidazole based thiadiazole and carbohydrazide conjugates as glycogen synthase kinase-3β inhibitors with anti-depressant activity.

    Science.gov (United States)

    Khan, Imran; Tantray, Mushtaq A; Hamid, Hinna; Alam, Mohammad Sarwar; Kalam, Abul; Dhulap, Abhijeet

    2016-08-15

    A series of benzimidazole based thiadiazole and carbohydrazide conjugates have been synthesized and evaluated for inhibition of glycogen synthase kinase-3β and anti-depressant effect. Compounds 4f, 4j, 5b, 5g and 5i were found to be the most potent inhibitors of GSK-3β in vitro amongst the twenty-five benzimidazole based thiadiazole and carbohydrazide conjugates synthesized. Compound 5i was also found to exhibit significant antidepressant activity in vivo at 50mg/kg, when compared to fluoxetine, a known antidepressant drug. The molecular docking studies revealed multiple hydrogen bond interactions by the synthesized compounds with various amino acid residues, viz, ASP-133, LYS-183, PRO-136, VAL-135, TYR-134, or LYS-60 at the GSK-3β receptor site. PMID:27406796

  19. Pharmacological profile of AW-814141, a novel, potent, selective and orally active inhibitor of p38 MAP kinase

    DEFF Research Database (Denmark)

    Chopra, Puneet; Kulkarni, Onkar; Gupta, Shashank;

    2010-01-01

    The p38 mitogen activated protein kinase (MAPK) is a key signaling molecule that plays a crucial role in the progression of various inflammatory diseases such as rheumatoid arthritis (RA), asthma and chronic obstructive pulmonary disease. The objective of the present study was to evaluate the anti...... and it displays promising in vitro and in vivo anti-inflammatory activities and can be used for the treatment of rheumatoid arthritis....... and collagen-induced arthritis model (CIA), AW-814141 dose dependently inhibited paw swelling. In different in vivo efficacy models, efficacy of AW-814141 was found to be better as compared to the reference compounds (Vx-745 and BIRB-796). This study demonstrated that AW-814141 is a novel p38 MAPK inhibitor...

  20. Targeting the mitotic checkpoint for cancer therapy with NMS-P715, an inhibitor of MPS1 kinase.

    Science.gov (United States)

    Colombo, Riccardo; Caldarelli, Marina; Mennecozzi, Milena; Giorgini, Maria Laura; Sola, Francesco; Cappella, Paolo; Perrera, Claudia; Depaolini, Stefania Re; Rusconi, Luisa; Cucchi, Ulisse; Avanzi, Nilla; Bertrand, Jay Aaron; Bossi, Roberto Tiberio; Pesenti, Enrico; Galvani, Arturo; Isacchi, Antonella; Colotta, Francesco; Donati, Daniele; Moll, Jürgen

    2010-12-15

    MPS1 kinase is a key regulator of the spindle assembly checkpoint (SAC), a mitotic mechanism specifically required for proper chromosomal alignment and segregation. It has been found aberrantly overexpressed in a wide range of human tumors and is necessary for tumoral cell proliferation. Here we report the identification and characterization of NMS-P715, a selective and orally bioavailable MPS1 small-molecule inhibitor, which selectively reduces cancer cell proliferation, leaving normal cells almost unaffected. NMS-P715 accelerates mitosis and affects kinetochore components localization causing massive aneuploidy and cell death in a variety of tumoral cell lines and inhibits tumor growth in preclinical cancer models. Inhibiting the SAC could represent a promising new approach to selectively target cancer cells.

  1. Melanoma-associated antigen expression and the efficacy of tyrosine kinase inhibitors in head and neck cancer

    DEFF Research Database (Denmark)

    Hartmann, Stefan; Brands, Roman C; Küchler, Nora;

    2015-01-01

    receptor (EGFR). The efficacy of tyrosine kinase inhibitors (TKI) in the context of melanoma-associated antigens is discussed in the present study. Five human squamous cell carcinoma cell lines were treated with the EGFR TKIs, erlotinib and gefitinib. The efficacy of these agents was measured using......Melanoma-associated antigen (MAGE) has been identified in a variety of types of cancer. The expression of several MAGE subgroups is correlated with poor prognosis and chemotherapeutic resistance. One target of chemotherapeutic treatment in head and neck cancer is the epidermal growth factor...... correlation between MAGE-A5 and -A11 and lower efficacy of EGFR TKIs. Pretreatment analysis of MAGE-A status may therefore aid improvement of chemoprevention using erlotinib and gefitinib in head and neck cancer....

  2. Anti-VEGF strategies - from antibodies to tyrosine kinase inhibitors: background and clinical development in human cancer.

    LENUS (Irish Health Repository)

    Korpanty, Grzegorz

    2012-01-01

    Tumour angiogenesis (formation of new blood vessels supporting tumour growth and metastasis) is a result of complex interactions between the tumour and the surrounding microenvironment. Targeting tumours with anti-angiogenic therapy remains an exciting area of preclinical and clinical studies. Although many significant advances have been achieved and the clinical use of anti-angiogenic drugs is now well recognized in many solid malignancies, these therapies fall short of their anticipated clinical benefits and leave many unanswered questions like exact mechanism of action, patients\\' selection and monitoring response to anti-angiogenic drugs. Tumour angiogenesis is controlled by complex signaling cascades and ongoing research into molecular mechanisms of tumour angiogenesis not only helps to understand its basic mechanisms but hopefully will identify new therapeutic targets. In 2012, both monoclonal antibodies and small molecule tyrosine kinase inhibitors remain the two major clinically useful therapeutic options that interfere with tumour angiogenesis in many solid malignancies.

  3. Trimodal Glioblastoma Treatment Consisting of Concurrent Radiotherapy, Temozolomide, and the Novel TGF-β Receptor I Kinase Inhibitor LY2109761

    Directory of Open Access Journals (Sweden)

    Mengxian Zhang

    2011-06-01

    Full Text Available Here we investigate the effects of the novel transforming growth factor-β receptor I (TGF-βRI serine/threonine kinase inhibitor LY2109761 on glioblastoma when combined with the present clinical standard combination regimen radiotherapy and temozolomide (TMZ. Human GBM U87 (methylated MGMT promoter, T98 (unmethylated MGMT promoter, and endothelial cells (HUVECs were treated with combinations of LY2109761, TMZ, and radiation. We found that LY2109761 reduced clonogenic survival of U87 and T98 cells and further enhanced the radiation-induced anticlonogenicity. In addition, LY2109761 had antimigratory and antiangiogenic effects in Matrigel migration and tube formation assays. In vivo, in human xenograft tumors growing subcutaneously on BALB/c nu/nu mice, LY2109761 delayed tumor growth alone and in combination with fractionated radiation and TMZ. Interestingly, as expected, the methylated U87 model was more sensitive to TMZ than the unmethylated T98 model in all experiments, whereas the opposite was found for LY2109761. Moreover, with respect to tumor angiogenesis, while LY2109761 decreased the glioblastoma proliferation index (Ki-67 and the microvessel density (CD31 count, the relative pericyte coverage (α-SMA/CD31 ratio increased in particular after triple therapy, suggesting a vascular normalization effect induced by LY2109761. This normalization could be attributed in part to a decrease in the Ang-2/Ang-1 messenger RNA ratio. LY2109761 also reduced tumor blood perfusion as quantified by noninvasive dynamic contrast-enhanced magnetic resonance imaging. Together, the data indicate that the addition of a TGF-βRI kinase inhibitor to the present clinical standard (radiation plus TMZ has the potential to improve clinical outcome in human glioblastoma, especially in patients with unmethylated MGMT promoter status.

  4. Differential Roles of Two Homologous Cyclin-Dependent Kinase Inhibitor Genes in Regulating Cell Cycle and Innate Immunity in Arabidopsis.

    Science.gov (United States)

    Hamdoun, Safae; Zhang, Chong; Gill, Manroop; Kumar, Narender; Churchman, Michelle; Larkin, John C; Kwon, Ashley; Lu, Hua

    2016-01-01

    Precise cell-cycle control is critical for plant development and responses to pathogen invasion. Two homologous cyclin-dependent kinase inhibitor genes, SIAMESE (SIM) and SIM-RELATED 1 (SMR1), were recently shown to regulate Arabidopsis (Arabidopsis thaliana) defense based on phenotypes conferred by a sim smr1 double mutant. However, whether these two genes play differential roles in cell-cycle and defense control is unknown. In this report, we show that while acting synergistically to promote endoreplication, SIM and SMR1 play different roles in affecting the ploidy of trichome and leaf cells, respectively. In addition, we found that the smr1-1 mutant, but not sim-1, was more susceptible to a virulent Pseudomonas syringae strain, and this susceptibility could be rescued by activating salicylic acid (SA)-mediated defense. Consistent with these results, smr1-1 partially suppressed the dwarfism, high SA levels, and cell death phenotypes in acd6-1, a mutant used to gauge the change of defense levels. Thus, SMR1 functions partly through SA in defense control. The differential roles of SIM and SMR1 are due to differences in temporal and spatial expression of these two genes in Arabidopsis tissues and in response to P. syringae infection. In addition, flow-cytometry analysis of plants with altered SA signaling revealed that SA is necessary, but not sufficient, to change cell-cycle progression. We further found that a mutant with three CYCD3 genes disrupted also compromised disease resistance to P. syringae. Together, this study reveals differential roles of two homologous cyclin-dependent kinase inhibitors in regulating cell-cycle progression and innate immunity in Arabidopsis and provides insights into the importance of cell-cycle control during host-pathogen interactions. PMID:26561564

  5. Weight loss induced by tyrosine kinase inhibitors of the vascular endothelial growth factor pathway.

    NARCIS (Netherlands)

    Desar, I.M.E.; Thijs, A.M.J.; Mulder, S.F.; Tack, C.J.J.; Herpen, C.M.L. van; Graaf, W.T.A. van der

    2012-01-01

    Weight loss, cachexia and sarcopenia are profound problems in the frail oncologic patients. With the development and increasing use of angiogenesis inhibitors in metastatic cancer patients, the question arises as to their influence on body weight and composition. Angiogenesis is not only important f

  6. BRAF kinase inhibitor exerts anti-tumor activity against breast cancer cells via inhibition of FGFR2.

    Science.gov (United States)

    Zhang, Zong Xin; Jin, Wen Jun; Yang, Sheng; Ji, Cun Li

    2016-01-01

    Most anti-angiogenic therapies currently being evaluated in clinical trials targetvascular endothelial growth factor (VEGF) pathway; however, the tumor vasculature can acquire resistance to VEGF-targeted therapy by shifting to other angiogenesis mechanisms. Therefore, other potential therapeutic agents that block non-VEGF angiogenic pathways need to be evaluated. Here we identified BRAF kinase inhibitor, vemurafenibas an agent with potential anti-angiogenic and anti-breast cancer activities. Vemurafenib demonstrated inhibition of endothelial cell proliferation, migration, and tube formation in response to basic fibroblast growth factor (bFGF). In ex vivo and in vivo angiogenesis assays, vemurafenib suppressed bFGF-induced microvessel sprouting of rat aortic rings and angiogenesis in vivo. To understand the underlying molecular basis, we examined the effects of vemurafenib on different molecular components in treated endothelial cell, and found that vemurafenib suppressed bFGF-triggered activation of FGFR2 and protein kinase B (AKT). Moreover, vemurafenib directly inhibited proliferation and blocked the oncogenic signaling pathways in breast cancer cell. In vivo, using xenograft models of breast cancer cells MDA-MB-231, vemurafenib showed growth-inhibitory activity associated with inhibition of tumor angiogenesis. Taken together, our results indicate that vemurafenib targets the FGFR2-mediated AKT signaling pathway in endothelial cells, leading to the suppression of tumor growth and angiogenesis.

  7. Molecular mechanism underlying the functional loss of cyclindependent kinase inhibitors pl6 and p27 in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Yasunobu Matsuda

    2008-01-01

    Hepatocellular carcinoma (HCC) is one of the most common human cancers, and its incidence is still increasing in many countries. The prognosis of HCC patients remains poor, and identification of useful molecular prognostic markers is required. Many recent studies have shown that functional alterations of cell-cycle regulators can be observed in HCC. Among the various types of cell-cycle regulators, pl6 and p27 are frequently inactivated in HCC and are considered to be potent tumor suppressors. pl6, a Gl-specific cell-cycle inhibitor that prevents the association of cyclindependent kinase (CDK) 4 and CDK6 with cyclin Dl, is frequently inactivated in HCC via CpG methylation of its promoter region. pl6 may be involved in the early steps of hepatocarcinogenesis, since pl6 gene methylation has been detected in subsets of pre-neoplastic liver cirrhosis patients. p27, a negative regulator of the Gl-S phase transition through inhibition of the kinase activities of Cdk2/cyclin A and Cdk2/cyclin E complexes, is now considered to be an adverse prognostic factor in HCC. In some cases of HCC with increased cell proliferation, p27 is overexpressed but inactivated by sequestration into cyclin Dl-CDK4-containing complexes. Since loss of pl6 is closely related to functional inactivation of p27 in HCC, investigating both pl6 and p27 may be useful for precise prognostic predictions in individuals with HCC.

  8. Structure-based design and development of (benz)imidazole pyridones as JAK1-selective kinase inhibitors.

    Science.gov (United States)

    Simov, Vladimir; Deshmukh, Sujal V; Dinsmore, Christopher J; Elwood, Fiona; Fernandez, Rafael B; Garcia, Yudith; Gibeau, Craig; Gunaydin, Hakan; Jung, Joon; Katz, Jason D; Kraybill, Brian; Lapointe, Blair; Patel, Sangita B; Siu, Tony; Su, Hua; Young, Jonathan R

    2016-04-01

    The mammalian Janus Kinases (JAK1, JAK2, JAK3 and TYK2) are intracellular, non-receptor tyrosine kinases whose activities have been associated in the literature and the clinic with a variety of hyperproliferative diseases and immunological disorders. At the onset of the program, it was hypothesized that a JAK1 selective compound over JAK2 could lead to an improved therapeutic index relative to marketed non-selective JAK inhibitors by avoiding the clinical AEs, such as anemia, presumably associated with JAK2 inhibition. During the course of the JAK1 program, a number of diverse chemical scaffolds were identified from both uHTS campaigns and de novo scaffold design. As part of this effort, a (benz)imidazole scaffold evolved via a scaffold-hopping exercise from a mature chemical series. Concurrent crystallography-driven exploration of the ribose pocket and the solvent front led to analogs with optimized kinome and JAK1 selectivities over the JAK2 isoform by targeting several residues unique to JAK1, such as Arg-879 and Glu-966. PMID:26927423

  9. A proteomic approach in investigating the hepatoprotective mechanism of Schisandrin B: role of raf kinase inhibitor protein.

    Science.gov (United States)

    Chen, Yan; Ip, Siu-Po; Ko, Kam-Ming; Poon, Terence C W; Ng, Eddy W Y; Lai, Paul B S; Mao, Qing-Qiu; Xian, Yan-Fang; Che, Chun-Tao

    2011-01-01

    To identify key proteins involved in the hepatoprotection afforded by schisandrin B (Sch B), we used a proteomic approach to screen proteins that were specifically regulated by Sch B in mouse livers and to investigate the role of the proteins in hepatoprotection. Thirteen proteins were specifically activated or suppressed by Sch B treatment. Among the 13 proteins, Raf kinase inhibitor protein (RKIP) was postulated to be the key regulator involved in the development of hepatotoxin-induced cellular damage. The results indicated that the downregulation of RKIP by antisense RKIP vector transfection led to the activation of the Raf-1/MEK/ERK signaling pathway, as evidenced by increases in the level of MEK/ERK phosphorylation and the level of nuclear factor erythroid 2-related factor 2 in the nucleus. The signaling effect produced by RKIP downregulation resembled that triggered by Sch B, wherein both treatments resulted in a decrease in the extent of carbon tetrachloride-induced apoptotic cell death in AML12 hepatocytes. Overexpression of RKIP by the sense RKIP transfection vector or the inhibition of MEK kinase by PD98059 was able to abrogate the cytoprotective effect of Sch B in the hepatocytes. The results indicate that Sch B triggers the Raf/MEK/ERK signaling pathway, presumably by downregulating RKIP, thereby protecting against carbon tetrachloride-induced cytotoxicity.

  10. Apoptotic induction in B-cell acute lymphoblastic leukemia cell lines treated with a protein kinaseinhibitor.

    Science.gov (United States)

    Saba, Nakhle S; Levy, Laura S

    2011-05-01

    B-cell acute lymphoblastic leukemia (B-ALL) in adults exhibits a 5-year disease-free survival rate of only 25-40% after currently available treatment. Protein kinase Cβ (PKCβ) is under active consideration as a rational therapeutic target in several B-cell malignancies, but studies of its possible utility in B-ALL are lacking. Expression of PKCβ1 and PKCβ2 isoforms was demonstrated in five B-ALL cell lines characterized by distinctive chromosomal translocations, and sensitivity to PKCβ-selective inhibition was examined. Inhibitor treatment resulted in a dose-dependent reduction in viability in all cell lines, although pro-B ALL with t(4;11)(q21;q23) was most sensitive. Apoptotic induction was evident after 24-48 h of treatment, and an inhibition of cell cycle progression was detected in one cell line. Treatment resulted in a rapid induction of poly(ADP-ribose) polymerase (PARP) cleavage, indicating caspase-3-mediated apoptosis, and a rapid reduction in phosphorylation of AKT and its downstream target glycogen synthase kinase 3β (GSK3β). These results indicate that PKCβ targeting should be considered as a potential treatment option in B-ALL.

  11. A unique hinge binder of extremely selective aminopyridine-based Mps1 (TTK) kinase inhibitors with cellular activity.

    Science.gov (United States)

    Kusakabe, Ken-ichi; Ide, Nobuyuki; Daigo, Yataro; Itoh, Takeshi; Yamamoto, Takahiko; Kojima, Eiichi; Mitsuoka, Yasunori; Tadano, Genta; Tagashira, Sachie; Higashino, Kenichi; Okano, Yousuke; Sato, Yuji; Inoue, Makiko; Iguchi, Motofumi; Kanazawa, Takayuki; Ishioka, Yukichi; Dohi, Keiji; Kido, Yasuto; Sakamoto, Shingo; Ando, Shigeru; Maeda, Masahiro; Higaki, Masayo; Yoshizawa, Hidenori; Murai, Hitoshi; Nakamura, Yusuke

    2015-05-01

    Mps1, also known as TTK, is a dual-specificity kinase that regulates the spindle assembly check point. Increased expression levels of Mps1 are observed in cancer cells, and the expression levels correlate well with tumor grade. Such evidence points to selective inhibition of Mps1 as an attractive strategy for cancer therapeutics. Starting from an aminopyridine-based lead 3a that binds to a flipped-peptide conformation at the hinge region in Mps1, elaboration of the aminopyridine scaffold at the 2- and 6-positions led to the discovery of 19c that exhibited no significant inhibition for 287 kinases as well as improved cellular Mps1 and antiproliferative activities in A549 lung carcinoma cells (cellular Mps1 IC₅₀=5.3 nM, A549 IC₅₀=26 nM). A clear correlation between cellular Mps1 and antiproliferative IC₅₀ values indicated that the antiproliferative activity observed in A549 cells would be responsible for the cellular inhibition of Mps1. The X-ray structure of 19c in complex with Mps1 revealed that this compound retains the ability to bind to the peptide flip conformation. Finally, comparative analysis of the X-ray structures of 19c, a deamino analogue 33, and a known Mps1 inhibitor bound to Mps1 provided insights into the unique binding mode at the hinge region. PMID:25801152

  12. Administration of a tropomyosin receptor kinase inhibitor attenuates sarcoma-induced nerve sprouting, neuroma formation and bone cancer pain

    Directory of Open Access Journals (Sweden)

    Bloom Aaron P

    2010-12-01

    Full Text Available Abstract Pain often accompanies cancer and most current therapies for treating cancer pain have significant unwanted side effects. Targeting nerve growth factor (NGF or its cognate receptor tropomyosin receptor kinase A (TrkA has become an attractive target for attenuating chronic pain. In the present report, we use a mouse model of bone cancer pain and examine whether oral administration of a selective small molecule Trk inhibitor (ARRY-470, which blocks TrkA, TrkB and TrkC kinase activity at low nm concentrations has a significant effect on cancer-induced pain behaviors, tumor-induced remodeling of sensory nerve fibers, tumor growth and tumor-induced bone remodeling. Early/sustained (initiated day 6 post cancer cell injection, but not late/acute (initiated day 18 post cancer cell injection administration of ARRY-470 markedly attenuated bone cancer pain and significantly blocked the ectopic sprouting of sensory nerve fibers and the formation of neuroma-like structures in the tumor bearing bone, but did not have a significant effect on tumor growth or bone remodeling. These data suggest that, like therapies that target the cancer itself, the earlier that the blockade of TrkA occurs, the more effective the control of cancer pain and the tumor-induced remodeling of sensory nerve fibers. Developing targeted therapies that relieve cancer pain without the side effects of current analgesics has the potential to significantly improve the quality of life and functional status of cancer patients.

  13. Antitumor activity of pimasertib, a selective MEK 1/2 inhibitor, in combination with PI3K/mTOR inhibitors or with multi-targeted kinase inhibitors in pimasertib-resistant human lung and colorectal cancer cells.

    Science.gov (United States)

    Martinelli, Erika; Troiani, Teresa; D'Aiuto, Elena; Morgillo, Floriana; Vitagliano, Donata; Capasso, Anna; Costantino, Sarah; Ciuffreda, Loreta Pia; Merolla, Francesco; Vecchione, Loredana; De Vriendt, Veerle; Tejpar, Sabine; Nappi, Anna; Sforza, Vincenzo; Martini, Giulia; Berrino, Liberato; De Palma, Raffaele; Ciardiello, Fortunato

    2013-11-01

    The RAS/RAF/MEK/MAPK and the PTEN/PI3K/AKT/mTOR pathways are key regulators of proliferation and survival in human cancer cells. Selective inhibitors of different transducer molecules in these pathways have been developed as molecular targeted anti-cancer therapies. The in vitro and in vivo anti-tumor activity of pimasertib, a selective MEK 1/2 inhibitor, alone or in combination with a PI3K inhibitor (PI3Ki), a mTOR inhibitor (everolimus), or with multi-targeted kinase inhibitors (sorafenib and regorafenib), that block also BRAF and CRAF, were tested in a panel of eight human lung and colon cancer cell lines. Following pimasertib treatment, cancer cell lines were classified as pimasertib-sensitive (IC50 for cell growth inhibition of 0.001 µM) or pimasertib-resistant. Evaluation of basal gene expression profiles by microarrays identified several genes that were up-regulated in pimasertib-resistant cancer cells and that were involved in both RAS/RAF/MEK/MAPK and PTEN/PI3K/AKT/mTOR pathways. Therefore, a series of combination experiments with pimasertib and either PI3Ki, everolimus, sorafenib or regorafenib were conducted, demonstrating a synergistic effect in cell growth inhibition and induction of apoptosis with sustained blockade in MAPK- and AKT-dependent signaling pathways in pimasertib-resistant human colon carcinoma (HCT15) and lung adenocarcinoma (H1975) cells. Finally, in nude mice bearing established HCT15 and H1975 subcutaneous tumor xenografts, the combined treatment with pimasertib and BEZ235 (a dual PI3K/mTOR inhibitor) or with sorafenib caused significant tumor growth delays and increase in mice survival as compared to single agent treatment. These results suggest that dual blockade of MAPK and PI3K pathways could overcome intrinsic resistance to MEK inhibition.

  14. Dissociation between skeletal muscle inhibitor-{kappa}B kinase/nuclear factor-{kappa}B pathway activity and insulin sensitivity in nondiabetic twins

    DEFF Research Database (Denmark)

    Friedrichsen, Martin; Ribel-Madsen, Rasmus; Wojtaszewski, Jørgen;

    2010-01-01

    Context: Several studies suggest a link between increased activity of the inflammatory inhibitor-kappaB kinase/nuclear factor-kappaB (IKK/NF-kappaB) pathway in skeletal muscle and insulin resistance. Objective: We aimed to study the regulation of skeletal muscle IKK/NF-kappaB pathway activity as ...

  15. Combined treatment of tyrosine kinase inhibitor labeled gold nanorod encapsulated albumin with laser thermal ablation in a renal cell carcinoma model

    Science.gov (United States)

    This manuscript served to characterize and evaluate Human Serum Albumin-encapsulated Nanoparticles (NPs) for drug delivery of a tyrosine kinase inhibitor combined with induction of photothermal ablation (PTA) combination therapy of Renal Cell Carcinoma (RCC). RCC is the most common type of kidney c...

  16. Structure-based drug design enables conversion of a DFG-in binding CSF-1R kinase inhibitor to a DFG-out binding mode.

    Science.gov (United States)

    Meyers, Marvin J; Pelc, Matthew; Kamtekar, Satwik; Day, Jacqueline; Poda, Gennadiy I; Hall, Molly K; Michener, Marshall L; Reitz, Beverly A; Mathis, Karl J; Pierce, Betsy S; Parikh, Mihir D; Mischke, Deborah A; Long, Scott A; Parlow, John J; Anderson, David R; Thorarensen, Atli

    2010-03-01

    The work described herein demonstrates the utility of structure-based drug design (SBDD) in shifting the binding mode of an HTS hit from a DFG-in to a DFG-out binding mode resulting in a class of novel potent CSF-1R kinase inhibitors suitable for lead development.

  17. Structure-based drug design enables conversion of a DFG-in binding CSF-1R kinase inhibitor to a DFG-out binding mode

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, Marvin J.; Pelc, Matthew; Kamtekar, Satwik; Day, Jacqueline; Poda, Gennadiy I.; Hall, Molly K.; Michener, Marshall L.; Reitz, Beverly A.; Mathis, Karl J.; Pierce, Betsy S.; Parikh, Mihir D.; Mischke, Deborah A.; Long, Scott A.; Parlow, John J.; Anderson, David R.; Thorarensen, Atli (Pfizer)

    2010-08-11

    The work described herein demonstrates the utility of structure-based drug design (SBDD) in shifting the binding mode of an HTS hit from a DFG-in to a DFG-out binding mode resulting in a class of novel potent CSF-1R kinase inhibitors suitable for lead development.

  18. Postextinction Infusion of a Mitogen-Activated Protein Kinase Inhibitor into the Medial Prefrontal Cortex Impairs Memory of the Extinction of Conditioned Fear

    Science.gov (United States)

    Hugues, Sandrine; Deschaux, Olivier; Garcia, Rene

    2004-01-01

    We investigated whether postextinction training infusion of PD098059, a selective inhibitor of mitogen-activated protein kinase (MAPK) activation, into the medial prefrontal cortex, would impair retention of extinction learning in rats. We found that immediate, but not late (2 or 4 h), postextinction infusion of PD098059 provoked a full return of…

  19. Rho kinase inhibitor y-27632 prolongs the life span of adult human keratinocytes, enhances skin equivalent development, and facilitates lentiviral transduction.

    NARCIS (Netherlands)

    Bogaard, E.H.J. van den; Rodijk-Olthuis, D.; Jansen, P.A.M.; Vlijmen-Willems, I.M.J.J. van; Erp, P.E.J. van; Joosten, I.; Zeeuwen, P.L.J.M.; Schalkwijk, J.

    2012-01-01

    The use of tissue-engineered human skin equivalents (HSE) for fundamental research and industrial application requires the expansion of keratinocytes from a limited number of skin biopsies donated by adult healthy volunteers or patients. A pharmacological inhibitor of Rho-associated protein kinases,

  20. The p38 MAP kinase inhibitor SB203580 enhances nuclear factor-kappa B transcriptional activity by a non-specific effect upon the ERK pathway

    NARCIS (Netherlands)

    Birkenkamp, KU; Tuyt, LML; Lummen, C; Wierenga, LTJ; Kruijer, W; Vellenga, E

    2000-01-01

    1 In the present study we investigated a possible role for the p38 mitogen-activated protein (MAP) kinase pathway in mediating nuclear factor-kappa B (NF-kappa B) transcriptional activity in the erythroleukaemic cell line TF-1. 2 TF-1 cells stimulated with the phosphatase inhibitor okadaic acid (OA)

  1. Novel irreversible EGFR tyrosine kinase inhibitor 324674 sensitizes human colon carcinoma HT29 and SW480 cells to apoptosis by blocking the EGFR pathway

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhiwei; Cui, Binbin; Jin, Yinghu; Chen, Haipeng [Division of Colorectal Surgery, Third Affiliated Hospital of Harbin Medical University, Harbin (China); Wang, Xishan, E-mail: wxshan_oncologist@yahoo.com.cn [Division of Colorectal Surgery, Third Affiliated Hospital of Harbin Medical University, Harbin (China)

    2011-08-12

    Highlights: {yields} This article described the effects of the EGFR tyrosine kinase inhibitor on the cell proliferation and the apoptosis induction of the colon carcinoma cell lines. {yields} Demonstrated that 326474 is a more potent EGFR inhibitor on colon cancer cells than other three TKIs. {yields} It can be important when considering chemotherapy for colonic cancer patients. -- Abstract: Background: Epidermal growth factor receptor (EGFR) is widely expressed in multiple solid tumors including colorectal cancer by promoting cancer cell growth and proliferation. Therefore, the inhibition of EGFR activity may establish a clinical strategy of cancer therapy. Methods: In this study, using human colon adenocarcinoma HT29 and SW480 cells as research models, we compared the efficacy of four EGFR inhibitors in of EGFR-mediated pathways, including the novel irreversible inhibitor 324674, conventional reversible inhibitor AG1478, dual EGFR/HER2 inhibitor GW583340 and the pan-EGFR/ErbB2/ErbB4 inhibitor. Cell proliferation was assessed by MTT analysis, and apoptosis was evaluated by the Annexin-V binding assay. EGFR and its downstream signaling effectors were examined by western blotting analysis. Results: Among the four inhibitors, the irreversible EGFR inhibitor 324674 was more potent at inhibiting HT29 and SW480 cell proliferation and was able to efficiently induce apoptosis at lower concentrations. Western blotting analysis revealed that AG1478, GW583340 and pan-EGFR/ErbB2/ErbB4 inhibitors failed to suppress EGFR activation as well as the downstream mitogen-activated protein kinase (MAPK) and PI3K/AKT/mTOR (AKT) pathways. In contrast, 324674 inhibited EGFR activation and the downstream AKT signaling pathway in a dose-dependent manner. Conclusion: Our studies indicated that the novel irreversible EGFR inhibitor 324674 may have a therapeutic application in colon cancer therapy.

  2. Prevention of pulmonary vascular and myocardial remodeling by the combined tyrosine and serine-/threonine kinase inhibitor, sorafenib, in pulmonary hypertension and right heart failure

    Directory of Open Access Journals (Sweden)

    M. Klein

    2008-06-01

    Full Text Available Inhibition of tyrosine kinases can reverse pulmonary hypertension but little is known about the role of serine-/threonine kinases in vascular and myocardial remodeling. We investigated the effects of sorafenib, an inhibitor of the tyrosine kinases VEGFR, PDGFR and c-kit as well as the serine-/threonine kinase Raf-1, in pulmonary hypertension and right ventricular (RV pressure overload. In monocrotaline treated rats, sorafenib (10 mg·kg–1·d–1 p.o. reduced pulmonary arterial pressure, pulmonary artery muscularization and RV hypertrophy, and improved systemic hemodynamics (table 1. Sorafenib prevented phosphorylation of Raf-1 and suppressed activation of downstream signaling pathways (Erk 1/2. After pulmonary banding, sorafenib, but not the PDGFR/c-KIT/ABL-inhibitor imatinib reduced RV mass and RV filling pressure significantly. Congruent with these results, sorafenib only prevented ERK phosphorylation and vasopressin induced hypertrophy of the cardiomyocyte cell line H9c2 dose dependently (IC50 = 300 nM. Combined inhibition of tyrosine and serine-/threonine kinases by sorafenib prevents vascular and cardiac remodeling in pulmonary hypertension, which is partly mediated via inhibition of the Raf kinase pathway.

  3. Take your PIK: PI-3-kinase inhibitors race through the clinic and towards cancer therapy

    OpenAIRE

    Ihle, Nathan T.; Powis, Garth

    2009-01-01

    The phosphatidylinositol-3-kinase / Akt signaling pathway is currently one of the most exciting drug targets in oncology. However only a short time ago, the paradigm existed that drugs targeted to the four PI3K class 1 isoforms would be too toxic for use in cancer therapy due to effects on physiological signaling. Since that time studies have delineated the roles of these four isoforms in non-pathological signaling as well as their roles in cancer. An extensive effort has gone into developing...

  4. Structure of the sporulation histidine kinase inhibitor Sda from Bacillus subtilis and insights into its solution state

    Energy Technology Data Exchange (ETDEWEB)

    Jacques, David A.; Streamer, Margaret [School of Molecular and Microbial Biosciences, University of Sydney (Australia); Rowland, Susan L.; King, Glenn F. [Institute of Molecular Biology, University of Queensland (Australia); Guss, J. Mitchell; Trewhella, Jill; Langley, David B., E-mail: d.langley@usyd.edu.au [School of Molecular and Microbial Biosciences, University of Sydney (Australia)

    2009-06-01

    The crystal structure of Sda, a DNA-replication/damage checkpoint inhibitor of sporulation in B. subtilis, has been solved via the MAD method. The subunit arrangement in the crystal has enabled a reappraisal of previous biophysical data, resulting in a new model for the behaviour of the protein in solution. The crystal structure of the DNA-damage checkpoint inhibitor of sporulation, Sda, from Bacillus subtilis, has been solved by the MAD technique using selenomethionine-substituted protein. The structure closely resembles that previously solved by NMR, as well as the structure of a homologue from Geobacillus stearothermophilus solved in complex with the histidine kinase KinB. The structure contains three molecules in the asymmetric unit. The unusual trimeric arrangement, which lacks simple internal symmetry, appears to be preserved in solution based on an essentially ideal fit to previously acquired scattering data for Sda in solution. This interpretation contradicts previous findings that Sda was monomeric or dimeric in solution. This study demonstrates the difficulties that can be associated with the characterization of small proteins and the value of combining multiple biophysical techniques. It also emphasizes the importance of understanding the physical principles behind these techniques and therefore their limitations.

  5. Metabolic alterations and drug sensitivity of tyrosine kinase inhibitor resistant leukemia cells with a FLT3/ITD mutation.

    Science.gov (United States)

    Huang, Amin; Ju, Huai-Qiang; Liu, Kaiyan; Zhan, Guilian; Liu, Daolu; Wen, Shijun; Garcia-Manero, Guillermo; Huang, Peng; Hu, Yumin

    2016-07-28

    Internal tandem duplication (ITD) of the juxtamembrane region of FMS-like tyrosine kinase-3 (FLT3) receptor is a common type of mutation in adult acute myeloid leukemia (AML), and patient response to FLT3 inhibitors appears to be transient due to the emergence of drug resistance. We established two sorafenib-resistant cell lines carrying FLT3/ITD mutations, including the murine BaF3/ITD-R and human MV4-11-R cell lines. Gene expression profile analysis of the resistant and parental cells suggests that the highest ranked molecular and cellular functions of the differentially expressed genes are related to mitochondrial dysfunction. Both murine and human resistant cell lines display a longer doubling time, along with a significant inhibition of mitochondrial respiratory chain activity and substantial upregulation of glycolysis. The sorafenib-resistant cells exhibit increased expression of a majority of glycolytic enzymes, including hexokinase 2, which is also highly expressed in the mitochondrial fraction and is associated with resistance to apoptotic cell death. The sorafenib-resistant cells are collaterally sensitive to a number of glycolytic inhibitors including 2-deoxyglucose and 3-bromopyruvate propylester. Our study reveals a metabolic signature of sorafenib-resistant cells and suggests that glycolytic inhibition may override such resistance and warrant further clinical investigation. PMID:27132990

  6. Application of docking and QM/MM-GBSA rescoring to screen for novel Myt1 kinase inhibitors.

    Science.gov (United States)

    Wichapong, Kanin; Rohe, Alexander; Platzer, Charlott; Slynko, Inna; Erdmann, Frank; Schmidt, Matthias; Sippl, Wolfgang

    2014-03-24

    Identification of compounds that can bind to a target protein with high affinity is a nontrivial task in structure-based drug design. Several approaches ranging from simple scoring methods to more computationally demanding methods are usually applied for this purpose. In the current work, we used ligand docking in combination with QM/MM-GBSA, MM-GBSA, and MM-PBSA rescoring to discriminate between active and inactive Myt1 kinase inhibitors. Results show that QM/MM-GBSA rescoring performs better than normal docking scores or MM-GBSA rescoring in classifying active and inactive inhibitors. We also applied QM/MM-GBSA rescoring to estimate the binding affinities of compounds from different virtual screening runs. To prove our approach and to confirm its predictive power, a few compounds which were predicted to be active were purchased and experimentally tested. Among the five selected compounds, three showed significant inhibition of recombinant Myt1. PD-173952, which yielded a favorable QM/MM-GBSA binding free energy, showed a K(i) value of 8.1 nM. In addition, two compounds, PD-180970 and saracatinib, showed inhibition at the low micromolar level. Thus, the developed protocol might be useful for further virtual screening experiments to better discriminate between active and inactive compounds and to further optimize the identified hits. PMID:24490903

  7. Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib.

    LENUS (Irish Health Repository)

    Kinsella, Paula

    2012-03-10

    High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC(50)). Response for each culture was compared with the EGFR\\/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-α expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile.

  8. Accurate calculation of mutational effects on the thermodynamics of inhibitor binding to p38α MAP kinase: a combined computational and experimental study.

    Science.gov (United States)

    Zhu, Shun; Travis, Sue M; Elcock, Adrian H

    2013-07-01

    A major current challenge for drug design efforts focused on protein kinases is the development of drug resistance caused by spontaneous mutations in the kinase catalytic domain. The ubiquity of this problem means that it would be advantageous to develop fast, effective computational methods that could be used to determine the effects of potential resistance-causing mutations before they arise in a clinical setting. With this long-term goal in mind, we have conducted a combined experimental and computational study of the thermodynamic effects of active-site mutations on a well-characterized and high-affinity interaction between a protein kinase and a small-molecule inhibitor. Specifically, we developed a fluorescence-based assay to measure the binding free energy of the small-molecule inhibitor, SB203580, to the p38α MAP kinase and used it measure the inhibitor's affinity for five different kinase mutants involving two residues (Val38 and Ala51) that contact the inhibitor in the crystal structure of the inhibitor-kinase complex. We then conducted long, explicit-solvent thermodynamic integration (TI) simulations in an attempt to reproduce the experimental relative binding affinities of the inhibitor for the five mutants; in total, a combined simulation time of 18.5 μs was obtained. Two widely used force fields - OPLS-AA/L and Amber ff99SB-ILDN - were tested in the TI simulations. Both force fields produced excellent agreement with experiment for three of the five mutants; simulations performed with the OPLS-AA/L force field, however, produced qualitatively incorrect results for the constructs that contained an A51V mutation. Interestingly, the discrepancies with the OPLS-AA/L force field could be rectified by the imposition of position restraints on the atoms of the protein backbone and the inhibitor without destroying the agreement for other mutations; the ability to reproduce experiment depended, however, upon the strength of the restraints' force constant