Kinetics of PKC epsilon Activating and Inhibiting Llama Single Chain Antibodies and Their Effect on PKC epsilon Translocation in HeLa Cells

Peer reviewe

Current Status and Future Prospects of C1 Domain Ligands as Drug Candidates

The second messenger diacylglycerol (DAG) plays a central role in the signal transduction of G-protein coupled receptors and receptor tyrosine kinases by binding to C1 domain of effector proteins. C1 domain was first identified in protein kinase C (PKC) which comprises a family of ten isoforms that play roles in diverse cellular processes such as proliferation, apoptosis and differentiation. Aberrant signaling through PKC isoforms and other C1 domain-containing proteins has been implicated in several pathological disorders. Drug discovery concerning C1 domains has exploited both natural products and rationally designed compounds. Currently, molecules from several classes of C1 domain-binding compounds are in clinical trials; however, still more have the potential to enter the drug development pipeline. This review gives a summary of the recent developments in C1 domain-binding compounds.Peer reviewe

C1 Domain-Targeted Isophthalate Derivatives Induce Cell Elongation and Cell Cycle Arrest in HeLa Cells

Peer reviewe

Evidence for a role of MRCK in mediating HeLa cell elongation induced by the C1 domain ligand HMI-1a3

Diacylglycerol (DAG) is a central mediator of signaling pathways that regulate cell proliferation, survival and apoptosis. Therefore, C1 domain, the DAG binding site within protein kinase C (PKC) and other DAG effector proteins, is considered a potential cancer drug target. Derivatives of 5-(hydroxymethyl)isophthalic acid are a novel group of C1 domain ligands with antiproliferative and differentiation-inducing effects. Our previous work showed that these isophthalate derivatives exhibit antiproliferative and elongation-inducing effects in HeLa human cervical cancer cells. In this study we further characterized the effects of bis(3-trifluoromethylbenzyl) 5-(hydroxymethyl)isophthalate (HMI-1a3) on HeLa cell proliferation and morphology. HMI-1a3-induced cell elongation was accompanied with loss of focal adhesions and actin stress fibers, and exposure to HMI-1a3 induced a prominent relocation of cofilin-1 into the nucleus regardless of cell phenotype. The antiproliferative and morphological responses to HMI-1a3 were not modified by coexposure to pharmacological inhibition or activation of PKC, or by RNAi knock-down of specific PKC isoforms, suggesting that the effects of HMI-1a3 were not mediated by PKC. Genome-wide gene expression microarray and gene set enrichment analysis suggested that, among others, HMI-1a3 induces changes in small GTPase-mediated signaling pathways. Our experiments revealed that the isophthalates bind also to the C1 domains of β2-chimaerin, protein kinase D (PKD) and myotonic dystrophy kinase-related Cdc42-binding kinase (MRCK), which are potential mediators of small GTPase signaling and cytoskeletal reorganization. Pharmacological inhibition of MRCK, but not that of PKD attenuated HMI-1a3-induced cell elongation, suggesting that MRCK participates in mediating the effects of HMI-1a3 on HeLa cell morphology.Peer reviewe

Design, synthesis, and biological activity of isophthalic acid derivatives targeted to the C1 domain of protein kinase C

Protein kinase C (PKC) is a widely studied molecular target for the treatment of cancer and other diseases. We have approached the issue of modifying PKC function by targeting the C1 domain in the regulatory region of the enzyme. Using the X-ray crystal structure of the PKC delta C1b domain, we have discovered conveniently synthesizable derivatives of dialkyl 5-(hydroxymethyl)isophthalate that can act as potential C1 domain ligands. Structure-activity studies confirmed that the important functional groups predicted by modeling were indispensable for binding to the C1 domain and that the modifications of these groups diminished binding. The most promising compounds were able to displace radiolabeled phorbol ester ([H-3]PDBu) from PKC alpha and delta at K-i values in the range of 200-900 nM. Furthermore, the active isophthalate derivatives could modify PKC activation in living cells either by inducing PKC-dependent ERK phosphorylation or by inhibiting phorbol-induced ERK phosphorylation. In conclusion, we report here, for the first time. that derivatives of isophthalic acid represent an attractive novel group of C1 domain ligands that can be used as research tools or further modified for potential drug development.Protein kinase C (PKC) is a widely studied molecular target for the treatment of cancer and other diseases. We have approached the issue of modifying PKC function by targeting the C1 domain in the regulatory region of the enzyme. Using the X-ray crystal structure of the PKC delta C1b domain, we have discovered conveniently synthesizable derivatives of dialkyl 5-(hydroxymethyl)isophthalate that can act as potential C1 domain ligands. Structure-activity studies confirmed that the important functional groups predicted by modeling were indispensable for binding to the C1 domain and that the modifications of these groups diminished binding. The most promising compounds were able to displace radiolabeled phorbol ester ([H-3]PDBu) from PKC alpha and delta at K-i values in the range of 200-900 nM. Furthermore, the active isophthalate derivatives could modify PKC activation in living cells either by inducing PKC-dependent ERK phosphorylation or by inhibiting phorbol-induced ERK phosphorylation. In conclusion, we report here, for the first time. that derivatives of isophthalic acid represent an attractive novel group of C1 domain ligands that can be used as research tools or further modified for potential drug development.Protein kinase C (PKC) is a widely studied molecular target for the treatment of cancer and other diseases. We have approached the issue of modifying PKC function by targeting the C1 domain in the regulatory region of the enzyme. Using the X-ray crystal structure of the PKC delta C1b domain, we have discovered conveniently synthesizable derivatives of dialkyl 5-(hydroxymethyl)isophthalate that can act as potential C1 domain ligands. Structure-activity studies confirmed that the important functional groups predicted by modeling were indispensable for binding to the C1 domain and that the modifications of these groups diminished binding. The most promising compounds were able to displace radiolabeled phorbol ester ([H-3]PDBu) from PKC alpha and delta at K-i values in the range of 200-900 nM. Furthermore, the active isophthalate derivatives could modify PKC activation in living cells either by inducing PKC-dependent ERK phosphorylation or by inhibiting phorbol-induced ERK phosphorylation. In conclusion, we report here, for the first time. that derivatives of isophthalic acid represent an attractive novel group of C1 domain ligands that can be used as research tools or further modified for potential drug development.Peer reviewe

Nanomaterials as part of society : Towards a safe future of nanotechnology

Nanomaterials as part of society : Towards a safe future of nanotechnologyThe review contains information on the use of nanomaterials and safety issues, regulation and research related to nanomaterials in Finland. Nanomaterials have at least one dimension between 1–100 nanometers. At the nanoscale, materials can exhibit unique chemical, physical, electronic and mechanical properties. Nanotechnology is used to improve the properties of materials. Manufactured nanomaterials are used in nearly all industrial sectors. As a result of human activity, nanoparticles are also generated unintentionally through various processes and combustion. The impact that nanomaterials have on health or the environment is not yet fully understood. The assessment of health and environmental risks is based on information on the hazardous properties and exposure levels of nanomaterials. Exposure to manufactured nanomaterials may occur during the production process or the use of these products. However, as a rule, the risk of exposure to manufactured nanomaterials in consumer products is minimal. The regulation of nanomaterials builds on EU and national legislation concerning chemicals, food and medicines. The EU also has sector-specific legislation on the safe use of nanomaterials. The European Commission is directing more and more funding to the research on the safety of nanomaterials. In Finland, universities and government research institutes conduct valuable safety and material-related research on nanomaterials

Nanomateriaalit osana yhteiskuntaa : Kohti turvallista nanoteknologian tulevaisuutta

Katsaus sisältää tietoa nanomateriaalien käytöstä, turvallisuuteen liittyvistä kysymyksistä, sääntelystä, sekä tutkimuksesta Suomessa. Nanomateriaaleissa vähintään yksi niiden ulottuvuus on välillä 1–100 nanometriä. Aineella voi nanokoossa olla kemiallisia, fysikaalisia, sähköisiä ja mekaanisia erityisominaisuuksia. Nanoteknologiaa käytetään tuotteiden ominaisuuksien parantamiseen. Teollisesti tuotettuja nanomateriaaleja käytetään lähes kaikilla teollisuuden aloilla. Ihmistoiminnan seurauksena syntyy myös tahattomasti poltto- ja prosessiperäisiä nanohiukkasia. Nanomateriaalien terveydelle tai ympäristölle aiheuttamia vaikutuksia ei vielä täysin tunneta. Terveys- ja ympäristöriskien arviointi perustuu tietoihin nanomateriaalien vaaraominaisuuksista ja altistumistasoista. Teollisesti tuotetuille nanomateriaaleille on mahdollista altistua valmistuksessa ja käytössä. Altistuminen kuluttajatuotteista on pääsääntöisesti vähäistä. Nanomateriaalien sääntelyssä sovelletaan EU- ja kansallisia säädöksiä, jotka koskevat kemikaaleja, elintarvikkeita tai lääkkeitä. Lisäksi EU:ssa on sektorikohtaisia säädöksiä nanomateriaalien turvalliselle käytölle. Euroopan komissio rahoittaa yhä enemmän nanomateriaalien turvallisuuteen liittyvää tutkimista. Suomen yliopistoissa ja valtion tutkimuslaitoksissa tehdään ansiokasta nanomateriaaleja koskevaa materiaali- ja turvallisuustutkimusta