bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Metformin in Experimentally Induced Animal Models of Epileptic Seizure
Authors: Yimer Ebrahim M. , Surur Awol , Wondafrash Dawit Zewdu , Gebre Abadi Kahsu
Published: February 2019

Background. Epilepsy is one of the common neurological illnesses which affects millions of individuals globally. Although the majority of epileptic patients have a good response for the currently available antiepileptic drugs (AEDs), about 30-40% of epileptic patients are developing resistance. In addition to low safety profiles of most of existing AEDs, there is no AED available for curative or disease-modifying actions for epilepsy so far.Objectives. This systematic review is intended to evaluate the effect of metformin in acute and chronic animal models of an epileptic seizure.Methods. We searched PubMed, SCOPUS, Sciences Direct, and grey literature in order to explore articles published in English from January 2010 to November 2018, using key terms “epilepsy,” “seizure,” “metformin,” “oral hypoglycemic agents,” and “oral antidiabetic drugs”. The qualities of all the included articles were assessed according to the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES).Results. Out of six hundred fifty original articles retrieved, eleven of them fulfilled the inclusion criteria and were included for final qualitative analysis. In these studies, metformin showed to control seizure attacks by attenuating seizure generation, delaying the onset of epilepsy, reducing hippocampal neuronal loss, and averting cognitive impairments in both acute and chronic models of an epileptic seizure. The possible mechanisms for its antiseizure or antiepileptic action might be due to activation of AMPK, antiapoptotic, antineuroinflammatory, and antioxidant properties, which possibly modify disease progression through affecting epileptogenesis.Conclusion. This review revealed the benefits of metformin in alleviating symptoms of epileptic seizure and modifying different cellular and molecular changes that affect the natural history of the disease in addition to its good safety profile.
Physical Incompatibility between Vancomycin and Viscoelastic Mimicking Acute Endophthalmitis: The First Report
Authors: Kuzmanović Elabjer Biljana , Šarić Dean , Bušić Mladen , Bjeloš Mirjana , Pleše Andrej
Published: February 2019

This is the first documentation of vancomycin precipitation with viscoelastic in the anterior chamber of the eye. A 34-year-old white male underwent uneventful penetrating keratoplasty. Intracameral instillation of 1 mg/0.1 mL of vancomycin followed no attempts of meticulous viscoelastic irrigation. Six hours later thick white material in the anterior chamber was sedimented. The following criteria excluded the diagnosis of endophthalmitis and TASS: clear and transparent anterior chamber and vitreous body, the absence of ciliary injection and corneal oedema, and unremarkable laboratory tests’ results. This iatrogenic complication mimicking endophthalmitis does not require any specific management and should be acknowledged in guidelines for prevention and treatment of endophthalmitis. The objective of this paper is to alert colleagues to this iatrogenic complication of vancomycin mimicking endophthalmitis. Whether this condition should be labelled as positive or negative demands further investigation. As vancomycin is a time-dependent antibiotic, it is possible that this precipitate could serve as a slowly releasing drug depot and viscoelastic as a vehicle for precipitation. This being the case, investigation is needed to analyse its potential to precipitate with another dispersive and cohesive viscoelasticity.
Significance of EGFR and PTEN Expression and PLR and NLR for Predicting the Prognosis of Epithelioid Malignant Peritoneal Mesothelioma
Authors: Liang Yufei , Zheng Guoqi , Yin Wenjie , Song Hui , Li Chunying , Tian Liang , Yang Dongliang
Published: February 2019

Objective. The aim of our study was to investigate the expression of EGFR and PTEN in tissues and measure the serum platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) to evaluate the prognostic factors of patients with epithelioid malignant peritoneal mesothelioma (MPeM). Methods. 33 patients of pathologically diagnosed epithelioid MPeM tissues were analyzed using immunohistochemistry to detect EGFR and PTEN; the PLR and NLR were determined by using a routine blood test. We analyzed the relationships of these markers to age, sex, asbestos exposure, elevated platelet count, ascites, and clinical stage. Results. EGFR and PTEN expressions were positive in 22 (66.67%) and 7 (21.21%) epithelioid MPeM patients, respectively. However, these two markers as well as PLR and NLR were not significantly associated with age, sex, asbestos exposure, elevated platelet counts, ascites, and clinical stage (P>0.05). The correlation between EGFR and PTEN was negative (r=−0.577, P<0.001), but the correlation between NLR and PLR was positive (r=0.456, P=0.008). The median survival of all patients was 6 months. In univariate analysis, PTEN (P<0.001), PLR (P=0.014), and NLR (P=0.015) affected the overall survival. Multivariate analysis revealed that PTEN and PLR were validated as predictive for overall survival of epithelioid MPeM (HR=0.070, P=0.001, and HR=3.379, P=0.007, respectively). Conclusion. On the basis of these results, it is suggested that PTEN and PLR are risk factors for the prognosis of epithelioid MPeM, which may be targets for selective therapies and improve the outcomes of patients with epithelioid MPeM.
Effects of In Ovo Injection of Coenzyme Q10 on Hatchability, Subsequent Performance, and Immunity of Broiler Chickens
Authors: Kalantar Majid , Hosseini Seyed Mahdi , Hosseini Mohammad Reza , Kalantar Mohammad Hassan , Farmanullah  , Yang Li Guo
Published: February 2019

Effects of in ovo injection of Q10 on hatchability, performance (feed intake (FI), body weight gain (BWG), feed/gain ratio (F/G)) traits, and immune status of Ross × Ross 308 broiler chicks, hatched from eggs laid by a 38-week-old breeder flock, were determined through 42 days after hatch. Eggs containing live embryos were injected in the amnion with 0.1 and 0.2 mL Q10 solution on day 18 of incubation. Two controls groups were included as sham and/or as an uninjected group. At 28 and 42 days of age, performance traits, serum enzyme activity, weights of immune organs, and serum antibody titer of viral diseases were determined. Results were shown that hatchability % increased by Q10 on average of 6.54% (P≤0.025) and body weight/egg weight after hatching increased up to 4.74% (P≤0.002), compared with uninjected and sham controls. Injection of Q10 at different levels led to significant increases (P≤0.001) in performance traits all over the rearing period (P<0.05). Weight of immune organs significantly improved compared to uninjected and sham controls (P<0.05). In addition, serum antibody titers of viral diseases as well as serum enzyme activity of AST, ALT, CAT, and SOD were significantly changed by Q10 treated groups than controls (P≤0.01). In conclusion, in ovo injection of Q10 at levels of 0.1 and 0.2 mL led to significant increases in hatchability%, internal egg characteristics, and performance parameters as well as serum enzyme activity, weight of immune organs, and serum antibody titer of ND, AI, and IBD diseases.
Effect of Size, Shape, and Composition on the Interaction of Different Nanomaterials with HeLa Cells
Authors: Renero-Lecuna Carlos , Iturrioz-Rodríguez Nerea , González-Lavado Eloisa , Padín-González Esperanza , Navarro-Palomares Elena , Valdivia-Fernández Lourdes , García-Hevia Lorena , Fanarraga Mónica L. , González-Legarreta Lorena
Published: February 2019

The application of nanomaterials in the fields of medicine and biotechnology is of enormous interest, particularly in the areas where traditional solutions have failed. Unfortunately, there is very little information on how to optimize the preparation of nanomaterials for their use in cell culture and on the effects that these can trigger on standard cellular systems. These data are pivotal in nanobiotechnology for the development of different applications and to evaluate/compare the cytotoxicity among the different nanomaterials or studies. The lack of information drives many laboratories to waste resources performing redundant comparative tests that often lead to partial answers due to differences in (i) the nature of the start-up material, (ii) the preparation, (iii) functionalization, (iv) resuspension, (v) the stability/dose of the nanomaterial, etc. These variations in addition to the different analytical systems contribute to the artefactual interpretation of the effects of nanomaterials and to inconsistent conclusions between different laboratories. Here, we present a brief review of a wide range of nanomaterials (nanotubes, various nanoparticles, graphene oxide, and liposomes) with HeLa cells as a reference cellular system. These human cells, widely used as cellular models for many studies, represent a reference system for comparative studies between different nanomaterials or conditions and, in the last term, between different laboratories.
Influence of Bath Temperature and Deposition Time on Topographical and Optical Properties of Nanoparticles ZnS Thin Films Synthesized by a Chemical Bath Deposition Method
Authors: Zein Raghad , Alghoraibi Ibrahim
Published: February 2019

In this paper, zinc sulfide nanoparticle (ZnS-NP) thin films were deposited onto glass substrates by chemical bath deposition using zinc sulfate as the cation precursor and thiourea as the anionic precursor. Different bath temperatures (65, 70, 75, and 80°C) and different deposition times (20, 30, 40, and 50 min) were selected to study the performance of ZnS thin films. Topographical and optical characterizations of the films were studied using the atomic force microscope (AFM) and UV-Vis spectroscope. The best ZnS thin films were deposited at a bath temperature (70°C) and a deposition time (30 min) with homogeneous distribution, high density, and small average diameter (106 nm). The energy gap (Eg) was found to be in the range of 4.05-3.97 eV for the ZnS films. Optical constants (refractive index, n, extinction coefficient, k, and dielectric constant, ε) of the films were obtained in the wavelength range 300-500 nm by using spectrophotometric measurement. The dispersion of the refractive index is analyzed by using a single oscillator model. The oscillator energy E0 and dispersion energy Ed were determined using the Wemple-DiDomenico single oscillator model. Urbach’s energy increases from 0.907 eV to 2.422 eV with increasing of deposition time. The calculated radius of nanoparticles using Brus equation was 1.9, 2.3, 2.45, and 2.51 nm at deposition times 20, 30, 40, and 50 min, respectively.
Algebraic Formulation for Moderately Thick Elastic Frames, Beams, Trusses, and Grillages within Timoshenko Theory
Authors: Pełczyński Jan , Gilewski Wojciech
Published: February 2019

The paper is dedicated to the algebraic formulation of elastic frame equations. The obtained set of equations describe deformations of moderately thick frames made of both compressible and incompressible bars, grillages of rigid or pin‐joined connections, and trusses. Plane as well as space structures are presented. The paper is an extension of the article of T. Lewiński written in 2001 related to thin bars. Algebraic equations with diagonal constitutive matrix are original and suitable for various engineering applications and for educational purposes.
Extreme Events in Lasers with Modulation of the Field Polarization
Authors: Gomel Alexis , Boyer Jean Marc , Metayer Cyrille , Tredicce Jorge R.
Published: February 2019

We develop a theoretical model for a unidirectional ring laser consisting of an isotropic active medium inside a cavity containing a birefringent Kerr cell. We analyze the dynamical behavior of the system as we modulate the voltage applied to the Kerr cell. We discuss the bifurcation diagram and we study the regions of control parameter space where it becomes possible to observe and predict extreme events.
The Relationship between Toll-like Receptors andHelicobacter pylori-Related Gastropathies: Still a Controversial Topic
Authors: Meliț Lorena Elena , Mărginean Cristina Oana , Mărginean Cristian Dan , Mărginean Maria Oana
Published: February 2019

Innate immunity represents the first barrier against bacterial invasion. Toll-like receptors (TLRs) belong to the large family of pattern recognition receptors (PRRs), and their activation leads to the induction of inflammatory cytokines, chemokines, antigen-presenting molecules, and costimulatory molecules. Recent studies have focused on identifying the association between TLRs andHelicobacter pylori- (H. pylori-) related diseases. Therefore, this minireview focuses on assessing the role of these TLRs in the development ofH. pylori-related gastropathies. Both TLR2 and TLR were found to be involved inH. pyloriLPS recognition, with contradictory results most likely due to both the inability to obtain pure LPS in experimental studies and the heterogeneity of the bacterial LPS. In addition,TLR2was found to be the most extensively expressed gene among all the TLRs in gastric tumors. High levels of TLR4 were also associated with a higher risk of gastric cancer. TLR5 was initially associated with the recognition ofH. pyloriflagellin, but it seems that this bacterium has developed mechanisms to escape this recognition representing an important factor involved in the persistence of this infection and subsequent carcinogenesis. TLR9, the only TLR with both anti- and proinflammatory roles, was involved in the recognition ofH. pyloriDNA. The dichotomous role of TLR9, promoting or suppressing the infection, depends on the gastric environment. Recently, TLR7 and TLR8 were shown to recognize purifiedH. pyloriRNA, thereby inducing proinflammatory cytokines.TLR1andTLR10gene polymorphisms were associated with a higher risk for gastric cancer inH. pylori-infected individuals. Different gene polymorphisms of these TLRs were found to be associated with gastric cancer depending mostly on ethnicity. Further studies are required in order to develop preventive and therapeutic strategies againstH. pyloriinfections based on the functions of TLRs.
Synthesis and Properties of a Reinforcing Dust-Cementing Material for Thin Spray-On Liners in Mine Roadways
Authors: Zhou Gang , Li Shuailong , Ma Yunlong , Ding Jianfei , Zhang Mingguang
Published: February 2019

The sprayed concrete in mine roadways suffers from a prolonged exposure to the harsh environment in the underground mine, leading to its detachment which may compromise its supporting strength. Besides, the dust-cementing effect of the conventional concrete is poor, providing very limited contribution to suppress the dust-laden airflow. As such, the present experiment uses sodium carboxymethyl cellulose as the base to produce a novel thin spray material through graft copolymerization based on acrylic acid and polyaluminum chloride. This new material can not only reinforce the surrounding rock of the roadway but also cement the dust in the airflow. Infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, and SEM are employed collectively to study the microscale reaction and structure of the product. A suite of experiment testing is carried out concerning the performance of the developed spray material, which reveals the supreme mechanical strength and desired properties of the hardened film developed from the spray material.
A New Model for Deriving the Priority Weights from Hesitant Triangular Fuzzy Preference Relations
Authors: Liu Yuan , Shen Gongtian , Zhao Zhangyan , Wu Zhanwen
Published: February 2019

Fuzzy preference relation is a common tool to express the uncertain preference information of decision maker in the process of decision making. However, the traditional fuzzy preference relation will fail under hesitant fuzzy environment as the membership has a single value. In addition, it is very difficult to obtain the precise membership values. Therefore, a new model of fuzzy preference relation is proposed in this paper. Firstly, the concept of hesitant triangular fuzzy preference relation is defined and its properties are investigated based on the concepts of hesitant fuzzy set, hesitant triangular fuzzy set, fuzzy preference relation, and hesitant fuzzy preference relation. Then, the steps of applying this novel model are offered for the case of determining the weights of failure modes. Finally, an example is used to illustrate the proposed model.
Solutions for a Class of Hadamard Fractional Boundary Value Problems with Sign-Changing Nonlinearity
Authors: Zhang Keyu , Fu Zhengqing
Published: February 2019

Using fixed point methods we establish some existence theorems of positive (nontrivial) solutions for a class of Hadamard fractional boundary value problems with sign-changing nonlinearity.
The Effect of Standardised Flower Extracts of Sorbus aucuparia L. on Proinflammatory Enzymes, Multiple Oxidants, and Oxidative/Nitrative Damage of Human Plasma Components In Vitro
Authors: Olszewska Monika A. , Kolodziejczyk-Czepas Joanna , Rutkowska Magdalena , Magiera Anna , Michel Piotr , Rejman Marcin W. , Nowak Pawel , Owczarek Aleksandra
Published: February 2019

Polyphenol-rich plant extracts might alleviate the negative impact of oxidative stress and inflammation, but careful phytochemical standardisation and evaluation of various mechanisms are required to fully understand their effects. In this context, flower extracts of Sorbus aucuparia L.—a traditional medicinal plant—were investigated in the present work. The LC-MS/MS profiling of the extracts, obtained by fractionated extraction, led to the identification of 66 constituents, mostly flavonols (quercetin and sexangularetin glycosides with dominating isoquercitrin), pseudodepsides of quinic and shikimic acids (prevailing isomers of chlorogenic acid and cynarin), and flavanols (catechins and proanthocyanidins). Minor extract components of possible chemotaxonomic value were flavalignans (cinchonain I isomers) and phenylamides (spermidine derivatives). As assessed by HPLC-PDA and UV-spectrophotometric studies, the extracts were polyphenol-abundant, with the contents up to 597.6 mg/g dry weight (dw), 333.9 mg/g dw, 382.0 mg/g dw, and 169.0 mg/g dw of total phenolics, flavonoids, proanthocyanidins, and caffeoylquinic acids, respectively. Their biological in vitro effects were phenolic-dependent and the strongest for diethyl ether, ethyl acetate, and n-butanol fractions of the methanol-water (7 : 3, v/v) extract. The extracts showed significant, concentration-dependent ability to scavenge in vivo-relevant radical/oxidant agents (O2∙−, OH∙, H2O2, ONOO–, NO∙, and HClO) with the strongest effects towards OH∙, ONOO–, HClO, and O2∙− (compared to ascorbic acid). Moreover, the extracts efficiently inhibited lipoxygenase and hyaluronidase (compared to indomethacin) but were inactive towards xanthine oxidase. At in vivo-relevant levels (1-5 μg/mL), they also effectively protected human plasma components (proteins and lipids) against ONOO–-induced oxidative damage (reduced the levels of 3-nitrotyrosine, lipid hydroperoxides, and thiobarbituric acid-reactive substances) and normalised/enhanced the total nonenzymatic antioxidant capacity of plasma. In cytotoxicity tests, the extracts did not affect the viability of human PBMCs and might be regarded as safe. The results support the application of the extracts in the treatment of oxidative stress-related pathologies cross-linked with inflammatory changes.
Targeting APLN/APLNR Improves Antiangiogenic Efficiency and Blunts Proinvasive Side Effects of VEGFA/VEGFR2 Blockade in Glioblastoma
Authors: Mastrella Giorgia , Hou Mengzhuo , Li Min , Stoecklein Veit M. , Zdouc Nina , Volmar Marie N.M. , Miletic Hrvoje , Reinhard Sören , Herold-Mende Christel C. , Kleber Susanne , Eisenhut Katharina , Gargiulo Gaetano , Synowitz Michael , Vescovi Angelo L. , Harter Patrick N. , Penninger Josef M. , Wagner Ernst , Mittelbronn Michel , Bjerkvig Rolf , Hambardzumyan Dolores , Schüller Ulrich , Tonn Jörg-Christian , Radke Josefine , Glass Rainer , Kälin Roland E.
Published: February 2019

Antiangiogenic therapy of glioblastoma (GBM) with bevacizumab, a VEGFA-blocking antibody, may accelerate tumor cell invasion and induce alternative angiogenic pathways. Here we investigate the roles of the proangiogenic apelin receptor APLNR and its cognate ligand apelin in VEGFA/VEGFR2 antiangiogenic therapy against distinct subtypes of GBM. In proneural GBM, apelin levels were downregulated by VEGFA or VEGFR2 blockade. A central role for apelin/APLNR in controlling GBM vascularization was corroborated in a serial implantation model of the angiogenic switch that occurs in human GBM. Apelin and APLNR are broadly expressed in human GBM, and knockdown or knockout of APLN in orthotopic models of proneural or classical GBM subtypes significantly reduced GBM vascularization compared with controls. However, reduction in apelin expression led to accelerated GBM cell invasion. Analysis of stereotactic GBM biopsies from patients as well as from in vitro and in vivo experiments revealed increased dissemination of APLNR-positive tumor cells when apelin levels were reduced. Application of apelin-F13A, a mutant APLNR ligand, blocked tumor angiogenesis and GBM cell invasion. Furthermore, cotargeting VEGFR2 and APLNR synergistically improved survival of mice bearing proneural GBM. In summary, we show that apelin/APLNR signaling controls GBM angiogenesis and invasion and that both pathologic features are blunted by apelin-F13A. We suggest that apelin-F13A can improve the efficiency and reduce the side effects of established antiangiogenic treatments for distinct GBM subtypes.

Significance:

Pharmacologic targeting of the APLNR acts synergistically with established antiangiogenic treatments in glioblastoma and blunts therapy resistance to current strategies for antiangiogenesis.

See related commentary by Amoozgar et al., p. 2104
Cooperative Effect of Oncogenic MET and PIK3CA in an HGF-Dominant Environment in Breast Cancer
Authors: Liu Shuying , Li Shunqiang , Wang Bailiang , Liu Wenbin , Gagea Mihai , Chen Huiqin , Sohn Joohyuk , Parinyanitikul Napa , Primeau Tina , Do Kim-Anh , Vande Woude George F. , Mendelsohn John , Ueno Naoto T. , Mills Gordon B. , Tripathy Debu , Gonzalez-Angulo Ana M.
Published: February 2019

There is compelling evidence that oncogenic MET and PIK3CA signaling pathways contribute to breast cancer. However, the activity of pharmacologic targeting of either pathway is modest. Mechanisms of resistance to these monotherapies have not been clarified. Currently, commonly used mouse models are inadequate for studying the HGF–MET axis because mouse HGF does not bind human MET. We established human HGF–MET paired mouse models. In this study, we evaluated the cooperative effects of MET and PIK3CA in an environment with involvement of human HGF in vivo. Oncogenic MET/PIK3CA synergistically induced aggressive behavior and resistance to each targeted therapy in an HGF-paracrine environment. Combined targeting of MET and PI3K abrogates resistance. Associated cell signaling changes were explored by functional proteomics. Consistently, combined targeting of MET and PI3K inhibited activation of associated oncogenic pathways. We also evaluated the response of tumor cells to HGF stimulation using breast cancer patient-derived xenografts (PDX). HGF stimulation induced significant phosphorylation of MET for all PDX lines detected to varying degrees. However, the levels of phosphorylated MET are not correlated with its expression, suggesting that MET expression level cannot be used as a sole criterion to recruit patients to clinical trials for MET-targeted therapy. Altogether, our data suggest that combined targeting of MET and PI3K could be a potential clinical strategy for breast cancer patients, where phosphorylated MET and PIK3CA mutation status would be biomarkers for selecting patients who are most likely to derive benefit from these cotargeted therapy.
Abstract A06: Inhibition of CD99 activity by clofarabine as a novel therapeutic for Ewing sarcoma involves a novel molecular mechanism that is different than cytarabine
Authors: Çelik Haydar , Sciandra Marika , Manara Maria Cristina , Torestky Jeffrey , Scotlandi Katia , Üren Aykut
Published: February 2019

Ewing sarcoma (ES) is an aggressive bone and soft tissue malignancy of unknown primary origin. ES cells express high levels of CD99, a cell surface protein routinely used as a marker antigen in the histologic diagnosis of ES. A substantial body of evidence makes CD99 an attractive therapeutic target for patients with ES. We identified two structurally similar FDA-approved nucleoside (purine) analogues, clofarabine and cladribine, as specific CD99 inhibitors in a Biacore screening experiment. In validation experiments, both drugs exhibited selective cytotoxicity toward ES cells in a panel of 14 ES vs. 28 non-ES cell lines. A membrane-impermeable derivative of clofarabine, clofarabine-5′-triphosphate, showed a similar cytotoxicity on ES cell lines, suggesting inhibition of CD99 activity on cell surface as a likely mechanism by which the drug exerts its cytotoxic action without any effect on DNA metabolism. Clofrabine also inhibited the growth of three different ES xenografts in vivo. We performed a phosphokinase array to identify the mechanism behind how clofarabine may regulate cellular functions through inhibiting CD99. Mitogen- and stress-activated kinases 1 and 2 (MSK1/2) were the most significantly activated proteins by both CD99 antibody and clofarabine. Four of the 7 proteins with increased phosphorylation were related to MSK1/2, which were MSK1/2 itself, its substrates CREB and c-Jun, and its upstream kinase ERK1/2, thus representing the most likely intracellular pathway responsible for cell death due to CD99 inhibition. Clofarabine induced a significant increase in phosphorylation levels of MSK1/2 in cohort of ES xenografts, supporting its use as a potential pharmacodynamic marker of CD99 inhibition. We compared the activity of clofarabine with cytarabine, a structurally similar pyrimidine analog that has been identified as an inhibitor of EWS/FLI1 transcriptional activity but failed in clinical trials on ES patients. Cytarabine did not activate MSK1/2 phosphorylation in ES cells, suggesting that clofarabine may function through alternative mechanisms on ES cells that are different than cytarabine. Overall, our findings suggest that clofarabine directly binds to CD99 and inhibits its oncogenic activity through a novel mechanism in ES, and therefore it is a good candidate for early-phase clinical trials in children with ES.

Citation Format: Haydar Çelik, Marika Sciandra, Maria Cristina Manara, Jeffrey Torestky, Katia Scotlandi, Aykut Üren. Inhibition of CD99 activity by clofarabine as a novel therapeutic for Ewing sarcoma involves a novel molecular mechanism that is different than cytarabine [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr A06.
Abstract A12: Tumorigenic proteins upregulated in pediatric neuroblastoma MYCN-amplified tumorspheres confer radiotherapy resistance
Authors: Abou-Antoun Tamara Mary , Abdallah Jad Helmi , Khazen George Antoun , Nasr Zeina , Sandler Anthony
Published: February 2019

Neuroblastoma is one of the most common extracranial central nervous system cancers of infancy with high mortality in children. We used SILAC proteomics to analyze the protein expression of the MYCN-amplified (IMR-32) and non-MYCN-amplified (SK-N-SH) human neuroblastoma stem-like tumorspheres after radiotherapy. More than 3,500 proteins were differentially expressed between the two cell types, and importantly many proteins were significantly upregulated in the IMR-32 compared to the SK-N-SH tumorspheres after radiotherapy, including the highly tumorigenic HSP90B (8-fold), prohibitin (4-fold), HMGA1 (15-fold), and FABP5 (3-fold). The top canonical pathways that the majority of the upregulated proteins in the neuroblastoma IMR-32 stem-like tumorspheres mapped to after radiotherapy included Actin Nucleation by ARP-WASP Complex; Signaling by Rho Family GTPases; Integrin Signaling; Cdc42 Signaling; and RhoGDI Signaling pathways. The associated network functions affiliated with these proteins were primarily cell death and survival, cell morphology, cellular function and maintenance; cell signaling, post-translational modification and protein synthesis; RNA post-transcriptional modification, molecular transport, RNA trafficking, and cancer. We sought to determine whether transcriptional knockdown of HMGA1 and FABP5 would radiosensitize these tumorspheres, as assessed by measuring the rate of cellular cytotoxicity, proliferation, and migration. IMR-32 neuroblastoma tumorspheres with transcriptional knockdown of HMGA1 and FABP5 exhibited lower rates of proliferation and migration, while cellular cytotoxicity was enhanced after 2Gy radiotherapy compared to nontransfected counterparts. Our finding suggests that HMGA1 and FABP5 may be contributing to the radiotherapy resistance of MYCN-amplified IMR-32 stem-like tumorspheres. Therapeutic resistance in the aggressive, MYCN-amplified high-risk group of pediatric neuroblastoma may be due to the upregulation of these highly tumorigenic proteins that are conferring protective mechanisms to this deadly childhood cancer.

Citation Format: Tamara Mary Abou-Antoun, Jad Helmi Abdallah, George Antoun Khazen, Zeina Nasr, Anthony Sandler. Tumorigenic proteins upregulated in pediatric neuroblastoma MYCN-amplified tumorspheres confer radiotherapy resistance [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr A12.
Abstract A14: Therapeutic targeting of KDM1A/LSD1 in Ewing sarcoma
Authors: Pishas Kathleen I. , Sharma Sunil , Lessnick Stephen L.
Published: February 2019

Objective: Multiagent chemotherapeutic regimes remain the cornerstone treatment for Ewing sarcoma, the second most common solid bone malignancy diagnosed in pediatric and young adolescent populations. We have reached a therapeutic ceiling with conventional cytotoxic agents, highlighting the need to adopt novel approaches that specifically target the drivers of Ewing sarcoma oncogenesis. As KDM1A/LSD1 (Lysine Specific Demethylase 1) is highly expressed in Ewing sarcoma cell lines and tumors, with elevated expression levels associated with worse overall survival (P=0.033), this study has examined biomarkers of sensitivity and mechanisms of cytotoxicity to targeted KDM1A inhibition using SP-2509 (reversible KDM1A inhibitor).

Methods: The antiproliferative effects of SP-2509 was determined through Cell Titre Glo assays following 72 hours of treatment in a comprehensive panel of 17 Ewing sarcoma cell lines with varying STAG2/TP53 mutational status and basal KDM1A expression levels. RNA-seq analysis of six Ewing sarcoma cell lines -/+ SP-2509 treatment (2μM) was also conducted.

Results: We report that innate resistance to SP-2509 was not observed in our Ewing sarcoma cell line cohort (72hr IC50 range 81nM-1593nM); in contrast, resistance to the next-generation KDM1A irreversible inhibitor GSK-LSD1 was observed across multiple cell lines (144hr IC50>300μM). Although TP53/STAG2 mutational status and basal KDM1A mRNA and protein levels did not correlate with SP-2509 response, induction of KDM1B (mammalian homologue of KDM1A) following SP-2509 treatment was strongly associated with SP-2509 hypersensitivity (R2=0.562). Indeed, shRNA-mediated knockdown of KDM1B significantly reduced the cytotoxic effects of SP-2509 (4.3-fold IC50 increase) only in hypersensitive cell lines. Mechanistically, RNA-seq analysis revealed that SP-2509 imparts robust apoptosis through engagement of the endoplasmic reticulum (ER) stress pathway, and that hypersensitive cell lines (IC50<300nM) share similar transcriptomic profiles. In addition, ETS1/ HIST1H2BM were specifically induced/repressed, respectively, following SP-2509 treatment only in our hypersensitive cell lines. Finally, we demonstrate that the transcriptional profile driven by SP-2509 strongly mirrors KDM1A genetic depletion.

Conclusion: Together, our findings provide key insights into the mechanisms of SP-2509 cytotoxicity as well as biomarkers that can be used to predict KDM1A inhibitor sensitivity in Ewing sarcoma.

Citation Format: Kathleen I. Pishas, Sunil Sharma, Stephen L. Lessnick. Therapeutic targeting of KDM1A/LSD1 in Ewing sarcoma [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr A14.
Abstract A37: Self-seeding resulting from tumor-tumor IL-6 signaling protects lungs from osteosarcoma metastasis
Authors: Saraf Amanda J. , Pommellet Helene Le , Gross Amy , Winget Sarah , Roberts Ryan D.
Published: February 2019

Metastatic osteosarcoma (OS) remains a fatal disease with overall survival less than 20%. The factors that drive metastasis remain poorly understood. Many have speculated on the biology that might drive development of metastasis after resection of a primary tumor. Our work suggests that OS tumors exhibit a high degree of self-seeding—“metastasis” of cancer cells back to the site of the primary tumor—and that circulating cells recolonize the primary tumor site preferentially over other sites. Removal of the primary tumor in orthotopic mouse models of OS triggers a redirection of circulating tumor cells toward colonization of alternative tissues, such as the lung. Mice that undergo amputation experience increased metastasis to the lungs relative to mice that continue to bear an orthotopic tumor. Our work demonstrates the involvement of IL-6 in the process of OS self-seeding. We show that osteosarcoma cells not only produce IL-6, but demonstrate directional migration and invasion in response to an IL6 gradient. Primary tumors engineered to lose the ability to produce IL6 demonstrate impairment of self-seeding and therefore become less able to “protect” from the development of lung metastasis. These results suggest that IL-6 is a primary mediator of tumor-tumor interactions that drive self-seeding in a process that might be amenable to therapeutic manipulation for the prevention of OS lung metastasis.

Citation Format: Amanda J. Saraf, Helene Le Pommellet, Amy Gross, Sarah Winget, Ryan D. Roberts. Self-seeding resulting from tumor-tumor IL-6 signaling protects lungs from osteosarcoma metastasis [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr A37.
Abstract A43: Deficiency of PTPRH in pediatric solid tumors identifies a high-risk phenotype that can be overcome by combinatorial tyrosine kinase inhibition
Authors: Scorsone Kathleen A. , Tyagi Siddhartha , Orellana Mayra C. , Gahlawat Sonal , Nair Amritha , Sun Tingting , Westbrook Thomas F. , Bernardi Ronald J.
Published: February 2019

As there is a paucity of targetable oncogenic drivers in pediatric solid tumors, we hypothesized that deficiency of select protein tyrosine phosphatases may allow proliferative signals to proceed unchecked in these cancers and that understanding these regulatory networks could inform therapy. In support of this possibility, the protein tyrosine phosphatase PTPRH has been previously reported to have a tumor-suppressive role in colon cancer and hepatocellular cancer. In the current study, we examine the role of PTPRH in pediatric solid tumors. Using multiple publicly available databases, we observed that low PTPRH expression is associated with significantly shorter survival in both neuroblastoma and osteosarcoma. Further, restoration of PTPRH expression in PTPRH-deficient neuroblastoma cells inhibits colony formation. In addition, we used a variety of biochemical approaches to identify novel PTPRH-binding partners and potential substrates. Moreover, we utilized these data to design combinatorial tyrosine kinase inhibitor therapies that target the cadre of receptor tyrosine kinases that are regulated by PTPRH. In particular, the combination of crizotinib and pazopanib inhibits proliferation of PTPRH-deficient neuroblastoma cells in vitro and reduces tumor growth in vivo. We are continuing to optimize the selection of tyrosine kinase inhibitors in order to most closely phenocopy restoration of PTPRH and maximize antitumor activity. Thus, we have shown that even for tumors that lack amplification or driver mutations of receptor tyrosine kinases, combinatorial tyrosine kinase inhibition can have substantial therapeutic activity and should be investigated further in the laboratory and the clinic.

Citation Format: Kathleen A. Scorsone, Siddhartha Tyagi, Mayra C. Orellana, Sonal Gahlawat, Amritha Nair, Tingting Sun, Thomas F. Westbrook, Ronald J. Bernardi. Deficiency of PTPRH in pediatric solid tumors identifies a high-risk phenotype that can be overcome by combinatorial tyrosine kinase inhibition [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr A43.
Abstract B11: The MuSiC2 system for discovery and visualization of coding and noncoding cancer drivers
Authors: Wyczalkowski Matthew A. , Bailey Matthew H. , Lou Carolyn , Hu Felix , Chen Justin Y. , Batra Prag , McLellan Michael D. , Ding Li , Wendl Michael C.
Published: February 2019

The MuSiC system has been widely used over the last 5 years by the scientific community for analyzing genomic data across the cancer spectrum. However, the desired scope of analysis has now increased dramatically, due to advances in instrumentation and experimental methods, vastly expanding sample availability, and the general appreciation of many newfound subtleties of the cancer initiation and progression processes themselves. We have extended MuSiC in several ways to address both new requirements and several long-standing issues that have not been manageable with any current analysis system. Here, we focus on three aspects. First, to answer the growing need for noncoding analysis, MuSiC2 extends the common idea of a “significantly mutated gene” model to one of “significantly mutated regions,” including the attendant tasks of interfacing to ENCODE, calculating region-appropriate background mutation rates (BMRs) for hypothesis testing, etc. Second, to address the statistical artifacts realized with most analysis software, we have designed two new filters: one for longer-than-average genes and another for cancer types having elevated BMRs, both scenarios of which typically show appreciably inflated false-positive rates because of upwardly biased passenger mutation counts. Finally, we describe a number of new visualization capabilities designed to give the investigator new interpretive capabilities, including for complex genomic rearrangements that may stem from viral integration. Taken together with improved programmatic efficiencies, the new MuSiC2 system should be useful for discovering and visualizing coding and noncoding cancer drivers in pediatric and adult cancers.

Citation Format: Matthew A. Wyczalkowski, Matthew H. Bailey, Carolyn Lou, Felix Hu, Justin Y. Chen, Prag Batra, Michael D. McLellan, Li Ding, Michael C. Wendl. The MuSiC2 system for discovery and visualization of coding and noncoding cancer drivers [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr B11.
Abstract B27: Anaplastic lymphoma kinase addicted neuroblastoma cell lines are associated with growth upon treatment with MEK inhibitor trametinib
Authors: Hallberg Bengt , Umapathy Ganseh , Guan Jikui , Gustafsson Dan , Javanmardi Niloufar , Cervantes-Madrid Diana , Djoos Anna , Martinsson Tommy , Palmer Ruth
Published: February 2019

The RAS-RAF-MEK-ERK pathway is a major player in initiation and progression of multiple cancers where it can be hyperactivated by upstream regulatory proteins, such as tyrosine kinases, phosphatases, and GTPases. Several inhibitors targeting the RAS-MAPK pathway exhibit anticancer activity and are approved as single agent in specific cancers. One such is the MEK inhibitor trametinib, which is included as a rational polytherapy strategy for treating EML4-ALK, EGFR, and K-RAS mutant lung cancer and neuroblastoma containing hyperactivating RAS-MAPK pathway mutations. In neuroblastoma, a heterogeneous disease, relapse cases display an increased rate of mutations of ALK, NRAS, and NF1 genes, leading to hyperactivation of RAS-MAPK signaling. Targeting the RAS-MAPK pathways offers attractive options for combinatorial treatment together with ALK inhibitors, since monotreatment has not yet produced strong clinical results in ALK-positive neuroblastoma patients. Here we investigate the response of ALK-positive neuroblastoma cell lines to MEK inhibition, employing trametinib. We show that pharmacologic inhibition of the MEK-ERK pathway in ALK-positive neuroblastoma cells results in increased levels of activation/phosphorylation of AKT and ERK5. This feedback response is regulated by the mTORC2 complex protein SIN1. Taken together, our results indicate that blocking MEK-ERK leads to increased activation of AKT signaling core in ALK-positive neuroblastoma, intensifying survival signals in these cells. Our results contraindicate use of MEK inhibitors as an effective single- and polytherapeutic strategy in ALK-positive neuroblastoma.

Citation Format: Bengt Hallberg, Ganseh Umapathy, Jikui Guan, Dan Gustafsson, Niloufar Javanmardi, Diana Cervantes-Madrid, Anna Djoos, Tommy Martinsson, Ruth Palmer. Anaplastic lymphoma kinase addicted neuroblastoma cell lines are associated with growth upon treatment with MEK inhibitor trametinib [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr B27.
Abstract IA02: Identity shifts in pediatric cancers
Authors: Delattre Olivier , Franzetti G.A. , Laud-Duval K. , Brisac A. , Boeva Valentina , Louis-Brennetot Caroline , Peltier Agathe , Durand Simon , Pierre-Eugène Cécile , Surdez Didier , Lapouble Eve , Pierron Gaelle , Grossetête-Lalami Sandrine , Janoueix-Lerosey Isabelle
Published: February 2019

In contrast to adult cancers, most pediatric malignancies display limited genetic heterogeneity. In Ewing sarcoma, the major driver of tumor development is the expression of the chimeric EWSR1-FLI1 transcription factor, which results from a chromosome translocation. Additional recurrent genetic alterations include the CDKN2A, STAG2, and TP53 genes. Through its binding to specific elements including GGAA microsatellite sequences, EWSR1-FLI1 has a major impact on epigenetic landscape of the cancer cells and consequently, obscures the epigenetic makeup of the Ewing cell-of-origin. The Ewing cell is somehow a “neomorphic” cell, the biologic properties of which are tightly dependent upon the expression level of EWSR1-FLI1. When a cell harbors a low level of expression of EWSR1-FLI1, it loses this neomorphic identity and retrieve its cell-of-origin, mesenchymal phenotype. This leads us to propose a new model of phenotypic plasticity whereby the dynamic fluctuation of the expression level of a dominant oncogene is an intrinsic characteristic of its oncogenic potential. The causes of EWSR1-FLI1 expression fluctuations are presently unknown. They may be partly stochastic as they are observed in cell lines in vitro but also dependent upon signals from the surrounding microenvironment. The situation is very different in neuroblastoma where the blueprint of the cell-of-origin, most frequently a noradrenergic progenitor, can be clearly detected whatever the genetic abnormalities of the cancer cells. Our recent data nevertheless suggest that neuroblastoma cells may also exhibit some plasticity and transition between different epigenetic states that witness different cell identities. In conclusion, pediatric cancers constitute simplified cancer systems to investigate the relative and interdependent contributions of genetic and nongenetic factors and to document identity shifts.

Citation Format: Olivier Delattre, G.A. Franzetti, K. Laud-Duval, A. Brisac, Valentina Boeva, Caroline Louis-Brennetot, Agathe Peltier, Simon Durand, Cécile Pierre-Eugène, Didier Surdez, Eve Lapouble, Gaelle Pierron, Sandrine Grossetête-Lalami, Isabelle Janoueix-Lerosey. Identity shifts in pediatric cancers [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr IA02.
Abstract IA10: Neuroblastoma is a biphasic tumor
Authors: Versteeg Rogier , Groningen Tim van , Koster Jan , Valentijn Linda J. , Nes Johan van
Published: February 2019

Neuroblastoma is a pediatric tumor of the peripheral adrenergic lineage, which is neural crest derived. During embryogenesis cells delaminate from the neural crest, migrate ventrally, and differentiate to (nor)-adrenalin producing cells. Neuroblastoma typically expresses differentiation markers of the adrenergic lineage. High-stage neuroblastoma usually goes in complete remission upon therapy but often relapses as resistant disease. Several tumor types were recently found to include phenotypically divergent cell types, resembling lineage development stages. We have found that most neuroblastoma includes two types of tumor cells with shared genomic defects, but highly diverging gene expression profiles. Undifferentiated mesenchymal cells (MES-type) and more differentiated adrenergic cells (ADRN-type) can interconvert and may relate to normal lineage differentiation stages. ChIP-seq analysis of isogenic pairs of MES- and ADRN-type cells revealed distinct, highly consistent super-enhancer landscapes for each cell type. Lineage identity has been proposed to ensue super-enhancer (SE)-associated transcription factor (TF) networks. We identified two SE-associated TF networks that potentially master each cell type. Accordingly, the mesenchymal TF PRRX1 could reprogram the SE- and mRNA-profiles of ADRN-type cells towards an MES-state. Assessment of the clinical relevance of this biphasic system revealed that MES-type cells were more chemoresistant in vitro and were enriched in post-therapy and relapsed tumors. The super enhancer-associated TF networks, probably meant for lineage control in normal development, thus could impose two cellular states of neuroblastoma that shape intratumor heterogeneity.

Citation Format: Rogier Versteeg, Tim van Groningen, Jan Koster, Linda J. Valentijn, Johan van Nes. Neuroblastoma is a biphasic tumor [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr IA10.