La presente invention concerne l'utilisation de sels de metal alcalin et, de preference, du c... more La presente invention concerne l'utilisation de sels de metal alcalin et, de preference, du chlorure de lithium pour le traitement de l'infestation d'abeilles melliferes par Varroa destructor .
Nanowires are a class of structures with useful electrical, optical, and mechanical properties th... more Nanowires are a class of structures with useful electrical, optical, and mechanical properties that vary significantly from those of the bulk material. Visible light diffraction is a simple and inexpensive optical method that is highly sensitive to the structure of the light scattering medium. Now,
BackgroundThe potentially lethal zoonosis alveolar echinococcosis (AE) is caused by the metacesto... more BackgroundThe potentially lethal zoonosis alveolar echinococcosis (AE) is caused by the metacestode larval stage of the tapeworm Echinococcus multilocularis. Current AE treatment options are limited and rely on surgery as well as on chemotherapy involving benzimidazoles (BZ). BZ treatment, however, is parasitostatic only, must be given for prolonged time periods, and is associated with adverse side effects. Novel treatment options are thus urgently needed.Methodology/Principal findingsBy applying a broad range of kinase inhibitors to E. multilocularis stem cell cultures we identified the proto-oncogene PIM kinase as a promising target for anti-AE chemotherapy. The gene encoding the respective E. multilocularis ortholog, EmPIM, was characterized and in situ hybridization assays indicated its expression in parasite stem cells. By yeast two-hybrid assays we demonstrate interaction of EmPIM with E. multilocularis CDC25, indicating an involvement of EmPIM in parasite cell cycle regulatio...
Introduction: Selinexor, a Selective Inhibitor of Nuclear Export (SINE) compound, is an anti-canc... more Introduction: Selinexor, a Selective Inhibitor of Nuclear Export (SINE) compound, is an anti-cancer drug that is currently being evaluated in Phase I and II clinical trials for the treatment of solid and hematological malignancies (clinicaltrials.gov). XPO1 (exportin 1/CRM1), the target of selinexor, is commonly overexpressed in cancer. XPO1 is the main nuclear export protein with over 200 different protein cargos which include tumor suppressor and growth regulatory proteins. Binding of selinexor to XPO1 inhibits the nuclear export of TSPs and GRPs and induces cell cycle arrest followed by cancer cell apoptosis.Certain cancers are more sensitive to selinexor than others. We hypothesized that part of the inherent differences in sensitivities are attributed to different levels of target inactivation upon selinexor binding. To predict patient response to treatment, we developed a binding assay based on Fluorescence Cross Correlation Spectroscopy (FCCS) to measure XPO1 target occupancy ...
Introduction: Selective Inhibitor of Nuclear Export (SINE) compounds are a new class of oral anti... more Introduction: Selective Inhibitor of Nuclear Export (SINE) compounds are a new class of oral anti-cancers drugs that block nuclear export by inhibiting the exportin XPO1 (also known as CRM1). The most advanced compounds in this class are selinexor and KPT-8602, which are being evaluated in clinical trials for the treatment of hematological malignancies (clinicaltrials.gov). XPO1 is commonly overexpressed in cancer and high levels of XPO1 are correlated with poor prognosis. Based on Phase I efficacy and safety studies, the recommended Phase 2 dose (RP2D) of selinexor is 60 mg twice weekly on days 1 and 3. We have previously reported the development of a pharmacodynamics (PD) assay to measure XPO1 target occupancy by selinexor in cancer cells based on Fluorescence Cross Correlation Spectroscopy (FCCS). Here we report proof of concept studies to determine the level of XPO1 occupancy associated with the selinexor RP2D regimen. Methods: Z138 cells in culture were treated with 1 µM seline...
Honey bees are increasingly important in the pollination of crops and wild plants. Recent reports... more Honey bees are increasingly important in the pollination of crops and wild plants. Recent reports of the weakening and periodical high losses of managed honey bee colonies have alarmed beekeeper, farmers and scientists. Infestations with the ectoparasitic mite Varroa destructor in combination with its associated viruses have been identified as a crucial driver of these health problems. Although yearly treatments are required to prevent collapses of honey bee colonies, the number of effective acaricides is small and no new active compounds have been registered in the past 25 years. RNAi-based methods were proposed recently as a promising new tool. However, the application of these methods according to published protocols has led to a surprising discovery. Here, we show that the lithium chloride that was used to precipitate RNA and other lithium compounds is highly effective at killing Varroa mites when fed to host bees at low millimolar concentrations. Experiments with caged bees and brood-free artificial swarms consisting of a queen and several thousand bees clearly demonstrate the potential of lithium as miticidal agent with good tolerability in worker bees providing a promising basis for the development of an effective and easy-to-apply control method for mite treatment.
Brain and leptomeningeal metastasis (LMM) of non-small cell lung cancer is still associated with ... more Brain and leptomeningeal metastasis (LMM) of non-small cell lung cancer is still associated with poor prognosis. Moreover, the current diagnostic standard for LMM often yields false negative results and the scientific progress in this field is still unsatisfying. We present a case of a 71-year old patient with an isolated LMM. While standard diagnostics could only diagnose a cancer of unknown primary, the use of [Ga]-Pentixafor-PET/CT (CXCR4-PET/CT, a radiotracer targeting CXCR4) and a liquid biopsy of the cerebrospinal fluid revealed the primary NSCLC. The detection of L858R-EGFR, a common driver mutation in NSCLC, enabled us to treat the patient with Afatinib and monitor treatment using [Ga]-Pentixafor PET/CT. To estimate the impact of CXCR4 signaling and its ligands in NSCLC brain metastasis we looked at their expression and correlation with EGFR mutations in a primary and brain metastasis data set and investigated the previously described binding of extracellular ubiquitin to CX...
XPO1 (exportin 1) is the main nuclear export protein with over 200 different protein cargos. XPO1... more XPO1 (exportin 1) is the main nuclear export protein with over 200 different protein cargos. XPO1 is overexpressed in tumor cells and high levels are correlated with poor prognosis. Selective Inhibitor of Nuclear Export (SINE) compounds block nuclear export by inhibiting XPO1. The first SINE compound, selinexor, shows promising anti-cancer activity across hematological and solid tumors in Phase 2 and 3 clinical trials. The 2nd generation SINE compound KPT-8602 is being evaluated as an anti-cancer agent in a Phase 1 clinical trial. To predict patient response to treatment and confirm the selinexor recommended phase 2 dose (RP2D), an assay based on fluorescence cross correlation spectroscopy that measures XPO1 occupancy in cancer cells was developed. Studies comparing cytotoxicity and XPO1 occupancy in cell lines treated with selinexor or KPT-8602 indicated that XPO1 occupancy by both compounds could reach saturation regardless of drug sensitivity. However, higher levels of XPO1 prote...
G protein-coupled receptors (GPCRs) mediate many important physiological functions and are consid... more G protein-coupled receptors (GPCRs) mediate many important physiological functions and are considered as one of the most successful therapeutic target classes for a wide spectrum of diseases. Drug discovery projects generally benefit from a broad range of experimental approaches for screening compound libraries and for the characterization of binding modes of drug candidates. Owing to the difficulties in solubilizing and purifying GPCRs, assay formats have been so far mainly limited to cell-based functional assays and radioligand binding assays. In this study, we used fluorescence cross-correlation spectroscopy (FCCS) to analyze the interaction of detergent-solubilized receptors to various types of GPCR ligands: endogenous peptides, small molecules, and a large surrogate antagonist represented by a blocking monoclonal antibody. Our work demonstrates the suitability of the homogeneous and time-resolved FCCS assay format for a robust, high-throughput determination of receptor-ligand b...
In the microRNA (miRNA) pathway, Dicer processes precursors to mature miRNAs. For efficient proce... more In the microRNA (miRNA) pathway, Dicer processes precursors to mature miRNAs. For efficient processing, double-stranded RNA-binding proteins support Dicer proteins. In flies, Loquacious (Loqs) interacts with Dicer1 (dmDcr1) to facilitate miRNA processing. Here, we have solved the structure of the third double-stranded RNA-binding domain (dsRBD) of Loqs and define specific structural elements that interact with dmDcr1. In addition, we show that the linker preceding dsRBD3 contributes significantly to dmDcr1 binding. Furthermore, our structural work demonstrates that the third dsRBD of Loqs forms homodimers. Mutations in the dimerization interface abrogate dmDcr1 interaction. Loqs, however, binds to dmDcr1 as a monomer using the identified dimerization surface, which suggests that Loqs might form dimers under conditions where dmDcr1 is absent or not accessible. Since critical sequence elements are conserved, we suggest that dimerization might be a general feature of dsRBD proteins in ...
MicroRNAs (miRNAs) guide Argonaute (Ago) proteins to distinct target mRNAs leading to translation... more MicroRNAs (miRNAs) guide Argonaute (Ago) proteins to distinct target mRNAs leading to translational repression and mRNA decay. Ago proteins interact with a member of the GW protein family, referred to as TNRC6A-C in mammals, which coordinate downstream gene-silencing processes. The cytoplasmic functions of TNRC6 and Ago proteins are reasonably well established. Both protein families are found in the nucleus as well. Their detailed nuclear functions, however, remain elusive. Furthermore, it is not clear which import routes Ago and TNRC6 proteins take into the nucleus. Using different nuclear transport assays, we find that Ago as well as TNRC6 proteins shuttle between the cytoplasm and the nucleus. While import receptors might function redundantly to transport Ago2, we demonstrate that TNRC6 proteins are imported by the Importin- pathway. Finally, we show that nuclear localization of both Ago2 and TNRC6 proteins can depend on each other suggesting actively balanced cytoplasmic Ago-TNRC6 levels.
photo-affinity linker and the cell lysates that overexressed DsRed or DsRedfused Pirin were used.... more photo-affinity linker and the cell lysates that overexressed DsRed or DsRedfused Pirin were used. Results: We identified a small-molecule that binds to Pirin by using the chemical array screening method. The K d value of the small-molecule to Pirin was 614 nM by isothermal titration calorimetry experiments. The pulldown assay showed that the small-molecule inhibited the interaction of Pirin with Bcl3 in vivo and in vitro. To get a insights into the effect of the small-moleclue against cells, we examined the cytotoxic activity against a number of different human cancer cell lines. As a result, the small-molecule did not show potent cytotoxic activity. In contrast, the inhibition of migration in melanoma cells was observed in the dose-dependent treatments of the small-molecule, but not the treatment of the negative control that does not bind to Pirin. We found that the treatment with the cultured tumor cells with the small-molecule or Pirin-targeted siRNA resulted in suppression of migration, but not cell proliferation. Conclusions: We have discovered the first inhibitor of Pirin, functions in cellular system is unclear. The inhibitor disrupted the interaction of Pirin with Bcl3 in vivo and in vitro. By use the inhibitor and siRNA, it is suggested that Pirin regulates migration of the tumor cells, and the inhibitor of Pirin might be a new chemotherapeutic potential for invasive tumors. 356 POSTER An innovative platform technology accelerates drug screening
La presente invention concerne l'utilisation de sels de metal alcalin et, de preference, du c... more La presente invention concerne l'utilisation de sels de metal alcalin et, de preference, du chlorure de lithium pour le traitement de l'infestation d'abeilles melliferes par Varroa destructor .
Nanowires are a class of structures with useful electrical, optical, and mechanical properties th... more Nanowires are a class of structures with useful electrical, optical, and mechanical properties that vary significantly from those of the bulk material. Visible light diffraction is a simple and inexpensive optical method that is highly sensitive to the structure of the light scattering medium. Now,
BackgroundThe potentially lethal zoonosis alveolar echinococcosis (AE) is caused by the metacesto... more BackgroundThe potentially lethal zoonosis alveolar echinococcosis (AE) is caused by the metacestode larval stage of the tapeworm Echinococcus multilocularis. Current AE treatment options are limited and rely on surgery as well as on chemotherapy involving benzimidazoles (BZ). BZ treatment, however, is parasitostatic only, must be given for prolonged time periods, and is associated with adverse side effects. Novel treatment options are thus urgently needed.Methodology/Principal findingsBy applying a broad range of kinase inhibitors to E. multilocularis stem cell cultures we identified the proto-oncogene PIM kinase as a promising target for anti-AE chemotherapy. The gene encoding the respective E. multilocularis ortholog, EmPIM, was characterized and in situ hybridization assays indicated its expression in parasite stem cells. By yeast two-hybrid assays we demonstrate interaction of EmPIM with E. multilocularis CDC25, indicating an involvement of EmPIM in parasite cell cycle regulatio...
Introduction: Selinexor, a Selective Inhibitor of Nuclear Export (SINE) compound, is an anti-canc... more Introduction: Selinexor, a Selective Inhibitor of Nuclear Export (SINE) compound, is an anti-cancer drug that is currently being evaluated in Phase I and II clinical trials for the treatment of solid and hematological malignancies (clinicaltrials.gov). XPO1 (exportin 1/CRM1), the target of selinexor, is commonly overexpressed in cancer. XPO1 is the main nuclear export protein with over 200 different protein cargos which include tumor suppressor and growth regulatory proteins. Binding of selinexor to XPO1 inhibits the nuclear export of TSPs and GRPs and induces cell cycle arrest followed by cancer cell apoptosis.Certain cancers are more sensitive to selinexor than others. We hypothesized that part of the inherent differences in sensitivities are attributed to different levels of target inactivation upon selinexor binding. To predict patient response to treatment, we developed a binding assay based on Fluorescence Cross Correlation Spectroscopy (FCCS) to measure XPO1 target occupancy ...
Introduction: Selective Inhibitor of Nuclear Export (SINE) compounds are a new class of oral anti... more Introduction: Selective Inhibitor of Nuclear Export (SINE) compounds are a new class of oral anti-cancers drugs that block nuclear export by inhibiting the exportin XPO1 (also known as CRM1). The most advanced compounds in this class are selinexor and KPT-8602, which are being evaluated in clinical trials for the treatment of hematological malignancies (clinicaltrials.gov). XPO1 is commonly overexpressed in cancer and high levels of XPO1 are correlated with poor prognosis. Based on Phase I efficacy and safety studies, the recommended Phase 2 dose (RP2D) of selinexor is 60 mg twice weekly on days 1 and 3. We have previously reported the development of a pharmacodynamics (PD) assay to measure XPO1 target occupancy by selinexor in cancer cells based on Fluorescence Cross Correlation Spectroscopy (FCCS). Here we report proof of concept studies to determine the level of XPO1 occupancy associated with the selinexor RP2D regimen. Methods: Z138 cells in culture were treated with 1 µM seline...
Honey bees are increasingly important in the pollination of crops and wild plants. Recent reports... more Honey bees are increasingly important in the pollination of crops and wild plants. Recent reports of the weakening and periodical high losses of managed honey bee colonies have alarmed beekeeper, farmers and scientists. Infestations with the ectoparasitic mite Varroa destructor in combination with its associated viruses have been identified as a crucial driver of these health problems. Although yearly treatments are required to prevent collapses of honey bee colonies, the number of effective acaricides is small and no new active compounds have been registered in the past 25 years. RNAi-based methods were proposed recently as a promising new tool. However, the application of these methods according to published protocols has led to a surprising discovery. Here, we show that the lithium chloride that was used to precipitate RNA and other lithium compounds is highly effective at killing Varroa mites when fed to host bees at low millimolar concentrations. Experiments with caged bees and brood-free artificial swarms consisting of a queen and several thousand bees clearly demonstrate the potential of lithium as miticidal agent with good tolerability in worker bees providing a promising basis for the development of an effective and easy-to-apply control method for mite treatment.
Brain and leptomeningeal metastasis (LMM) of non-small cell lung cancer is still associated with ... more Brain and leptomeningeal metastasis (LMM) of non-small cell lung cancer is still associated with poor prognosis. Moreover, the current diagnostic standard for LMM often yields false negative results and the scientific progress in this field is still unsatisfying. We present a case of a 71-year old patient with an isolated LMM. While standard diagnostics could only diagnose a cancer of unknown primary, the use of [Ga]-Pentixafor-PET/CT (CXCR4-PET/CT, a radiotracer targeting CXCR4) and a liquid biopsy of the cerebrospinal fluid revealed the primary NSCLC. The detection of L858R-EGFR, a common driver mutation in NSCLC, enabled us to treat the patient with Afatinib and monitor treatment using [Ga]-Pentixafor PET/CT. To estimate the impact of CXCR4 signaling and its ligands in NSCLC brain metastasis we looked at their expression and correlation with EGFR mutations in a primary and brain metastasis data set and investigated the previously described binding of extracellular ubiquitin to CX...
XPO1 (exportin 1) is the main nuclear export protein with over 200 different protein cargos. XPO1... more XPO1 (exportin 1) is the main nuclear export protein with over 200 different protein cargos. XPO1 is overexpressed in tumor cells and high levels are correlated with poor prognosis. Selective Inhibitor of Nuclear Export (SINE) compounds block nuclear export by inhibiting XPO1. The first SINE compound, selinexor, shows promising anti-cancer activity across hematological and solid tumors in Phase 2 and 3 clinical trials. The 2nd generation SINE compound KPT-8602 is being evaluated as an anti-cancer agent in a Phase 1 clinical trial. To predict patient response to treatment and confirm the selinexor recommended phase 2 dose (RP2D), an assay based on fluorescence cross correlation spectroscopy that measures XPO1 occupancy in cancer cells was developed. Studies comparing cytotoxicity and XPO1 occupancy in cell lines treated with selinexor or KPT-8602 indicated that XPO1 occupancy by both compounds could reach saturation regardless of drug sensitivity. However, higher levels of XPO1 prote...
G protein-coupled receptors (GPCRs) mediate many important physiological functions and are consid... more G protein-coupled receptors (GPCRs) mediate many important physiological functions and are considered as one of the most successful therapeutic target classes for a wide spectrum of diseases. Drug discovery projects generally benefit from a broad range of experimental approaches for screening compound libraries and for the characterization of binding modes of drug candidates. Owing to the difficulties in solubilizing and purifying GPCRs, assay formats have been so far mainly limited to cell-based functional assays and radioligand binding assays. In this study, we used fluorescence cross-correlation spectroscopy (FCCS) to analyze the interaction of detergent-solubilized receptors to various types of GPCR ligands: endogenous peptides, small molecules, and a large surrogate antagonist represented by a blocking monoclonal antibody. Our work demonstrates the suitability of the homogeneous and time-resolved FCCS assay format for a robust, high-throughput determination of receptor-ligand b...
In the microRNA (miRNA) pathway, Dicer processes precursors to mature miRNAs. For efficient proce... more In the microRNA (miRNA) pathway, Dicer processes precursors to mature miRNAs. For efficient processing, double-stranded RNA-binding proteins support Dicer proteins. In flies, Loquacious (Loqs) interacts with Dicer1 (dmDcr1) to facilitate miRNA processing. Here, we have solved the structure of the third double-stranded RNA-binding domain (dsRBD) of Loqs and define specific structural elements that interact with dmDcr1. In addition, we show that the linker preceding dsRBD3 contributes significantly to dmDcr1 binding. Furthermore, our structural work demonstrates that the third dsRBD of Loqs forms homodimers. Mutations in the dimerization interface abrogate dmDcr1 interaction. Loqs, however, binds to dmDcr1 as a monomer using the identified dimerization surface, which suggests that Loqs might form dimers under conditions where dmDcr1 is absent or not accessible. Since critical sequence elements are conserved, we suggest that dimerization might be a general feature of dsRBD proteins in ...
MicroRNAs (miRNAs) guide Argonaute (Ago) proteins to distinct target mRNAs leading to translation... more MicroRNAs (miRNAs) guide Argonaute (Ago) proteins to distinct target mRNAs leading to translational repression and mRNA decay. Ago proteins interact with a member of the GW protein family, referred to as TNRC6A-C in mammals, which coordinate downstream gene-silencing processes. The cytoplasmic functions of TNRC6 and Ago proteins are reasonably well established. Both protein families are found in the nucleus as well. Their detailed nuclear functions, however, remain elusive. Furthermore, it is not clear which import routes Ago and TNRC6 proteins take into the nucleus. Using different nuclear transport assays, we find that Ago as well as TNRC6 proteins shuttle between the cytoplasm and the nucleus. While import receptors might function redundantly to transport Ago2, we demonstrate that TNRC6 proteins are imported by the Importin- pathway. Finally, we show that nuclear localization of both Ago2 and TNRC6 proteins can depend on each other suggesting actively balanced cytoplasmic Ago-TNRC6 levels.
photo-affinity linker and the cell lysates that overexressed DsRed or DsRedfused Pirin were used.... more photo-affinity linker and the cell lysates that overexressed DsRed or DsRedfused Pirin were used. Results: We identified a small-molecule that binds to Pirin by using the chemical array screening method. The K d value of the small-molecule to Pirin was 614 nM by isothermal titration calorimetry experiments. The pulldown assay showed that the small-molecule inhibited the interaction of Pirin with Bcl3 in vivo and in vitro. To get a insights into the effect of the small-moleclue against cells, we examined the cytotoxic activity against a number of different human cancer cell lines. As a result, the small-molecule did not show potent cytotoxic activity. In contrast, the inhibition of migration in melanoma cells was observed in the dose-dependent treatments of the small-molecule, but not the treatment of the negative control that does not bind to Pirin. We found that the treatment with the cultured tumor cells with the small-molecule or Pirin-targeted siRNA resulted in suppression of migration, but not cell proliferation. Conclusions: We have discovered the first inhibitor of Pirin, functions in cellular system is unclear. The inhibitor disrupted the interaction of Pirin with Bcl3 in vivo and in vitro. By use the inhibitor and siRNA, it is suggested that Pirin regulates migration of the tumor cells, and the inhibitor of Pirin might be a new chemotherapeutic potential for invasive tumors. 356 POSTER An innovative platform technology accelerates drug screening
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