PI3K/AKT/mTOR inhibition in combination with doxorubicin is an effective therapy for leiomyosarcoma.

BackgroundLeiomyosarcoma (LMS) is a common type of soft tissue sarcoma that responds poorly to standard chemotherapy. Thus the goal of this study was to identify novel selective therapies that may be effective in leiomyosarcoma by screening cell lines with a small molecule library comprised of 480 kinase inhibitors to functionally determine which signalling pathways may be critical for LMS growth.MethodsLMS cell lines were screened with the OICR kinase library and a cell viability assay was used to identify potentially effective compounds. The top 10 % of hits underwent secondary validation to determine their EC50 and immunoblots were performed to confirm selective drug action. The efficacy of combination drug therapy with doxorubicin (Dox) in vitro was analyzed using the Calcusyn program after treatment with one of three dosing schedules: concurrent treatment, initial treatment with a selective compound followed by Dox, or initial treatment with Dox followed by the selective compound. Single and combination drug therapy were then validated in vivo using LMS xenografts.ResultsCompounds that targeted PI3K/AKT/mTOR pathways (52 %) were most effective. EC50s were determined to validate these initial hits, and of the 11 confirmed hits, 10 targeted PI3K and/or mTOR pathways with EC50 values <1 μM. We therefore examined if BEZ235 and BKM120, two selective compounds in these pathways, would inhibit leiomyosarcoma growth in vitro. Immunoblots confirmed on-target effects of these compounds in the PI3K and/or mTOR pathways. We next investigated if there was synergy with these agents and first line chemotherapy doxorubicin (Dox), which would allow for earlier introduction into patient care. Only combined treatment of BEZ235 and Dox was synergistic in vitro. To validate these findings in pre-clinical models, leiomyosarcoma xenografts were treated with single agent and combination therapy. BEZ235 treated xenografts (n = 8) demonstrated a decrease in tumor volume of 42 % whereas combining BEZ235 with Dox (n = 8) decreased tumor volume 68 % compared to vehicle alone.ConclusionsIn summary, this study supports further investigation into the use of PI3K and mTOR inhibitors alone and in combination with standard treatment in leiomyosarcoma patients

Full lifetime perspectives on the costs and benefits of lay date variation in tree swallows

Animals must balance various costs and benefits when deciding when to breed. The costs and benefits of breeding at different times have received much attention, but most studies have been limited to investigating short-term season-to-season fitness effects. However, breeding early, versus late, in a season may influence lifetime fitness over many years, trading off in complex ways across the breeder?s lifepan. In this study, we examined the complete life histories of 867 female tree swallows (Tachycineta bicolor) breeding in Ithaca, New York, between 2002 and 2016. Earlier breeders outperformed later breeders in short-term measures of reproductive output and offspring quality. Though there were weak indications that females paid long-term future survival costs for breeding early, lifetime fledgling output was markedly higher overall in early-breeding birds. Importantly, older females breeding later in the season did not experience compensating life-history advantages that suggested an alternative equal-fitness breeding strategy. Rather, most or all of the swallows appear to be breeding as early as they can, and differences in lay dates appear to be determined primarily by differences in individual quality or condition. Lay date had a significant repeatability across breeding attempts by the same female, and the first lay date of females fledged in our population was strongly influenced by the first lay date of their mothers, indicating the potential for ongoing selection on lay date. By examining performance over the entire lifespan of a large number of individuals, we were able to clarify the relationship between timing of breeding and fitness and gain new insight into the sources of variability in this important life history trait.Fil: Winkler, David Ward. Cornell University; Estados UnidosFil: Hallinger, Kelly K.. Cornell University; Estados UnidosFil: Pegan, Teresa M.. University of Michigan; Estados UnidosFil: Taff, Conor C.. Cornell University; Estados UnidosFil: Verhoeven, Mo A.. University of Groningen; Países BajosFil: Van Oordt, David Chang. Cornell University; Estados UnidosFil: Stager, Maria. University of Montana; Estados UnidosFil: Uehling, Jennifer J.. Cornell University; Estados UnidosFil: Vitousek, Maren N.. Cornell University; Estados UnidosFil: Andersen, Michael J.. University of New Mexico; Estados UnidosFil: Ardia, Daniel R.. Franklin & Marshall College; Estados UnidosFil: Belmaker, Amos. Tel Aviv University; IsraelFil: Ferretti, Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Forsman, Anna M.. University Of Central Florida; Estados UnidosFil: Gaul, Jennifer R.. International High School at La Guardia Community College; Estados UnidosFil: Llambias, Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Orzechowski, Sophia C.. Harvard University; Estados UnidosFil: Shipley, Ryan. Max Planck Institute For Animal Behavior; AlemaniaFil: Wilson, Maya. Virginia Polytechnic Institute. Department Of Geological Sciences; Estados UnidosFil: Yoon, Hyun Seok. University of Tennessee; Estados Unido

G Protein-Coupled Receptor Kinase 6 (GRK6) Regulates Insulin Processing and Secretion via Effects on Proinsulin Conversion to Insulin

Recent studies identified a missense mutation in the gene coding for G protein-coupled receptor kinase 6 (GRK6) that segregates with type 2 diabetes (T2D). To better understand how GRK6 might be involved in T2D, we used pharmacological inhibition and genetic knockdown in the mouse β-cell line, MIN6, to determine whether GRK6 regulates insulin dynamics. We show inhibition of GRK5 and GRK6 increased insulin secretion but reduced insulin processing while GRK6 knockdown revealed these same processing defects with reduced levels of cellular insulin. GRK6 knockdown cells also had attenuated insulin secretion but enhanced proinsulin secretion consistent with decreased processing. In support of these findings, we demonstrate GRK6 rescue experiments in knockdown cells restored insulin secretion after glucose treatment. The altered insulin profile appears to be caused by changes in the proprotein convertases, the enzymes responsible for proinsulin to insulin conversion, as GRK6 knockdown resulted in significantly reduced convertase expression and activity. To identify how the GRK6-P384S mutation found in T2D patients might affect insulin processing, we performed biochemical and cell biological assays to study the properties of the mutant. We found that while GRK6-P384S was more active than WT GRK6, it displayed a cytosolic distribution in cells compared to the normal plasma membrane localization of GRK6. Additionally, GRK6 overexpression in MIN6 cells enhanced proinsulin processing, while GRK6-P384S expression had little effect. Taken together, our data show that GRK6 regulates insulin processing and secretion in a glucose-dependent manner and provide a foundation for understanding the contribution of GRK6 to T2D

Spallation reactions. A successful interplay between modeling and applications

The spallation reactions are a type of nuclear reaction which occur in space by interaction of the cosmic rays with interstellar bodies. The first spallation reactions induced with an accelerator took place in 1947 at the Berkeley cyclotron (University of California) with 200 MeV deuterons and 400 MeV alpha beams. They highlighted the multiple emission of neutrons and charged particles and the production of a large number of residual nuclei far different from the target nuclei. The same year R. Serber describes the reaction in two steps: a first and fast one with high-energy particle emission leading to an excited remnant nucleus, and a second one, much slower, the de-excitation of the remnant. In 2010 IAEA organized a worskhop to present the results of the most widely used spallation codes within a benchmark of spallation models. If one of the goals was to understand the deficiencies, if any, in each code, one remarkable outcome points out the overall high-quality level of some models and so the great improvements achieved since Serber. Particle transport codes can then rely on such spallation models to treat the reactions between a light particle and an atomic nucleus with energies spanning from few tens of MeV up to some GeV. An overview of the spallation reactions modeling is presented in order to point out the incomparable contribution of models based on basic physics to numerous applications where such reactions occur. Validations or benchmarks, which are necessary steps in the improvement process, are also addressed, as well as the potential future domains of development. Spallation reactions modeling is a representative case of continuous studies aiming at understanding a reaction mechanism and which end up in a powerful tool.Comment: 59 pages, 54 figures, Revie

Small molecule epigenetic screen identifies novel EZH2 and HDAC inhibitors that target glioblastoma brain tumor-initiating cells

Glioblastoma (GBM) is the most lethal and aggressive adult brain tumor, requiring the development of efficacious therapeutics. Towards this goal, we screened five genetically distinct patient-derived brain-tumor initiating cell lines (BTIC) with a unique collection of small molecule epigenetic modulators from the Structural Genomics Consortium (SGC). We identified multiple hits that inhibited the growth of BTICs in vitro, and further evaluated the therapeutic potential of EZH2 and HDAC inhibitors due to the high relevance of these targets for GBM. We found that the novel SAM-competitive EZH2 inhibitor UNC1999 exhibited low micromolar cytotoxicity in vitro on a diverse collection of BTIC lines, synergized with dexamethasone (DEX) and suppressed tumor growth in vivo in combination with DEX. In addition, a unique brain-penetrant class I HDAC inhibitor exhibited cytotoxicity in vitro on a panel of BTIC lines and extended survival in combination with TMZ in an orthotopic BTIC model in vivo. Finally, a combination of EZH2 and HDAC inhibitors demonstrated synergy in vitro by augmenting apoptosis and increasing DNA damage. Our findings identify key epigenetic modulators in GBM that regulate BTIC growth and survival and highlight promising combination therapies

Data from: Developmental temperature predicts the adult response to stressors in a free-living passerine

Thumbnail Image: Photo of nest box in pond, taken by David Chang van Oordt.Update Note: Uehling_etal_adult_CORT_weather.csv and this readme file were updated on 2019-11-25, by J.J.U. Additional measurements were added (A.Mass.Inc, A.Mass.Prov), and new records were added in the A.Wing and A.Headbill measurements.Early life conditions can have substantial effects on the ways animals respond to stressors as adults. In particular, thermal conditions during development affect juveniles’ responses to stressors, and there is evidence that these effects may extend into adulthood. However, these effects remain poorly understood, especially in free-living organisms. We test the prediction that ambient temperatures during laying, embryonic development, and nestling development affect the hormonal mediators of the response to stressors in adults. To do so, we use a long-term dataset of tree swallows (Tachycineta bicolor) with records from both natal development and adult breeding. We found a strong, negative relationship between ambient temperature during early development (incubation) and an individual’s corticosterone (CORT) response to stress later in life (while incubating her own young). Thermal conditions during other stages of natal development also showed weak relationships with CORT phenotype in other adult life history stages (baseline CORT during incubation; baseline CORT and the CORT response to stress during provisioning). In a post-hoc analysis, we found no evidence that ambient temperature during development differentially influenced the survival and recruitment of juveniles with different CORT phenotypes. Our results show that thermal conditions during development can have long-term effects on how individuals respond to stressors. This dataset supports the above conclusions.This work was supported by NSF IOS-1457251 to M.N.V.; NSF LTREB DEB-0717021, IOS-0744753, and DEB-1242573 to D.W.W., and NSF GRFP DGE-1650441 to J.J.U

A Widely Applicable Dual-Catalytic System for Cross-Electrophile Coupling

A new dual catalytic system for cross-electrophile coupling reactions between aryl and alkyl halides that features a Ni catalyst, a Co co-catalyst, and a mild homogeneous reductant, is described. This is a unique combination of reagents for cross-electrophile coupling reactions, which results in one of the most versatile systems reported to date. For example, the coupling of aryl bromides and aryl iodides with alkyl bromides, alkyl iodides, alkyl mesylates, and benzyl chlorides is demonstrated under similar reaction conditions. The system is tolerant of numerous functional groups and is capable of coupling heteroaryl halides, di-ortho-substituted aryl halides, pharmaceutically relevant drug-like aryl halides, and a diverse range of alkyl halides. Additionally, the dual catalytic platform facilitates a series of novel one-pot three-component cross-electrophile coupling reactions of bromo(iodo)arenes with two distinct alkyl halides. Mechanistic studies indicate that the Ni catalyst activates the aryl halide electrophile, while the Co catalyst activates the alkyl electrophile