bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preservation of reserve intestinal epithelial stem cells following severe ischemic injury
Authors: Gonzalez Liara M. , Stewart Amy Stieler , Freund John , Kucera Cecilia Renee , Dekaney Christopher M. , Magness Scott T. , Blikslager Anthony T. 
Published: February 2019

Intestinal ischemia is an abdominal emergency with a mortality rate >50%, leading to epithelial barrier loss and subsequent sepsis. Epithelial renewal and repair after injury depend on intestinal epithelial stem cells (ISC) that reside within the crypts of Lieberkühn. Two ISC populations critical to epithelial repair have been described: 1) active ISC (aISC; highly proliferative; leucine-rich-repeat-containing G protein-coupled receptor 5 positive, sex determining region Y-box 9 positive) and 2) reserve ISC [rISC; less proliferative; homeodomain only protein X (Hopx)+]. Yorkshire crossbred pigs (8–10 wk old) were subjected to 1–4 h of ischemia and 1 h of reperfusion or recovery by reversible mesenteric vascular occlusion. This study was designed to evaluate whether ISC-expressing biomarkers of aISCs or rISCs show differential resistance to ischemic injury and different contributions to the subsequent repair and regenerative responses. Our data demonstrate that, following 3–4 h ischemic injury, aISC undergo apoptosis, whereas rISC are preserved. Furthermore, these rISC are retained ex vivo in spheroids in which cell populations are enriched in the rISC biomarker Hopx. These cells appear to go on to provide a proliferative pool of cells during the recovery period. Taken together, these data indicate that Hopx+cells are resistant to injury and are the likely source of epithelial renewal following prolonged ischemic injury. It is therefore possible that targeting reserve stem cells will lead to new therapies for patients with severe intestinal injury.NEW & NOTEWORTHY The population of reserve less-proliferative intestinal epithelial stem cells appears resistant to injury despite severe epithelial cell loss, including that of the active stem cell population, which results from prolonged mesenteric ischemia. These cells can change to an activated state and are likely indispensable to regenerative processes. Reserve stem cell targeted therapies may improve treatment and outcome of patients with ischemic disease.
Cerium Oxide Nanoparticles Regulate Insulin Sensitivity and Oxidative Markers in 3T3-L1 Adipocytes and C2C12 Myotubes
Authors: Lopez-Pascual Amaya , Urrutia-Sarratea Andoni , Lorente-Cebrián Silvia , Martinez J. Alfredo , González-Muniesa Pedro 
Published: February 2019

Insulin resistance is associated with oxidative stress, mitochondrial dysfunction, and a chronic low-grade inflammatory status. In this sense, cerium oxide nanoparticles (CeO2 NPs) are promising nanomaterials with antioxidant and anti-inflammatory properties. Thus, we aimed to evaluate the effect of CeO2 NPs in mouse 3T3-L1 adipocytes, RAW 264.7 macrophages, and C2C12 myotubes under control or proinflammatory conditions. Macrophages were treated with LPS, and both adipocytes and myotubes with conditioned medium (25% LPS-activated macrophages medium) to promote inflammation. CeO2 NPs showed a mean size of ≤25.3 nm (96.7%) and a zeta potential of 30.57±0.58 mV, suitable for cell internalization. CeO2 NPs reduced extracellular reactive oxygen species (ROS) in adipocytes with inflammation while increased in myotubes with control medium. The CeO2 NPs increased mitochondrial content was observed in adipocytes under proinflammatory conditions. Furthermore, the expression of Adipoq and Il10 increased in adipocytes treated with CeO2 NPs. In myotubes, both Il1b and Adipoq were downregulated while Irs1 was upregulated. Overall, our results suggest that CeO2 NPs could potentially have an insulin-sensitizing effect specifically on adipose tissue and skeletal muscle. However, further research is needed to confirm these findings.
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

Abstract

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

Abstract
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

Abstract
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

Abstract
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

Abstract
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&gt;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&lt;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

Abstract
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

Abstract
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.