bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of 18β-Glycyrrhetinic Acid on Fungal Protease-Induced Airway Inflammatory Responses
Authors: Kim Yun Hee , Kim Dong Eon , Lee Seung-Hyo
Published: May 2018

Airway epithelial cells secrete diverse inflammatory mediators in response to various stimuli. Thus, early regulation of immune responses in the airway epithelium is likely critical for the control of chronic inflammatory diseases. The purpose of the present study was to evaluate the effects of 18β-glycyrrhetinic acid (GA) on inflammatory responses generated in response to a fungal protease allergen that induces epithelial damage. To understand the underlying mechanisms, we also investigated the inhibitory effects of GA on the production of mitochondrial reactive oxygen species (ROS) in the human bronchial epithelial cell line BEAS2B. In this study, GA treatment reduced cytokine production and the human neutrophil cell line HL60 migration through decreased mitochondrial ROS production. In addition, GA significantly reduced inflammatory cell infiltration and cytokine levels in the bronchoalveolar lavage (BAL) fluid of fungal allergen-administered mice. Inhibitory effects of GA are dependent on the mitochondrial ROS/MAPK axis. Moreover, the effect of GA on the regulation of mitochondrial ROS depends on the expression of uncoupling protein-2 (UCP-2). Taken together, GA might represent a potential therapeutic agent for blocking inflammatory responses in airways.
On Max-Plus Algebra and Its Application on Image Steganography
Authors: Santoso Kiswara Agung , Fatmawati  , Suprajitno Herry
Published: May 2018

We propose a new steganography method to hide an image into another image using matrix multiplication operations on max-plus algebra. This is especially interesting because the matrix used in encoding or information disguises generally has an inverse, whereas matrix multiplication operations in max-plus algebra do not have an inverse. The advantages of this method are the size of the image that can be hidden into the cover image, larger than the previous method. The proposed method has been tested on many secret images, and the results are satisfactory which have a high level of strength and a high level of security and can be used in various operating systems.
Endovascular Treatment of Thoracic Aortic Aneurysm Causing Life-Threatening Hemoptysis: Two Case Reports
Authors: Oğuz Şükrü , Bekirçavuşoğlu Süleyman , Pulathan Zerrin
Published: May 2018

Purpose. To describe two patients presenting life-threatening hemoptysis with saccular thoracic aortic aneurysm penetrating lung parenchyma and its endovascular treatment. Case Report. We present two cases of 73- and 74-year-old men with massive hemoptysis secondary to saccular thoracic aortic aneurysm ruptured lung parenchyma who were successfully treated with endovascular approach with 3rd month’s imaging follow-up. Conclusion. Thoracic aortic aneurysm is one of the rarest causes of hemoptysis and thoracic endovascular aortic repair (TEVAR) and can be used for an effective and problem-solving treatment approach.
Difference between the Upper and the Lower Gastrointestinal Bleeding in Patients Taking Nonvitamin K Oral Anticoagulants
Authors: Maruyama Kyohei , Yamamoto Takatsugu , Aoyagi Hitoshi , Isono Akari , Abe Koichiro , Kodashima Shinya , Kita Hiroto , Watari Yuji , Kozuma Ken
Published: May 2018

Nonvitamin K oral anticoagulants (NOACs) sometimes cause hemorrhage, and the gastrointestinal tract is a common site of involvement. However, clinical characteristics of gastrointestinal bleeding (GIB) during NOAC therapy have not been fully elucidated. We studied 658 patients who were prescribed dabigatran, rivaroxaban, or apixaban between April 2011 and November 2015. Medical charts were reviewed to examine whether clinically relevant bleeding (Bleeding Academic Research Consortium criteria type 2 or greater) developed. The incidence of GIB was 2.0%/year, and one-third was from the upper GI. Among all hemorrhagic events, GIB was the most common cause. The extent of bleeding from the GI tract, particularly the upper GI tract, was more serious than bleeding from the other site. Multiple regression analysis showed that both past digestive ulcer and absence of concomitant proton pump inhibitors were significantly associated with the incidence of upper GIB, while concomitant nonsteroidal anti-inflammatory drugs, dual antiplatelets, and past GIB were significant factors regarding lower GIB. GIB was common and serious in patients taking NOACs. Upper GIB tended to become more serious than lower GIB. Proton pump inhibitors seem to be key drugs for preventing upper GIB during NOAC therapy.
Treatment of Full-Thickness Rotator Cuff Tendon Tear Using Umbilical Cord Blood-Derived Mesenchymal Stem Cells and Polydeoxyribonucleotides in a Rabbit Model
Authors: Kwon Dong Rak , Park Gi-Young , Lee Sang Chul
Published: May 2018

Objective. The aim of this study was to investigate regenerative effects of ultrasound- (US-) guided injection with human umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) and/or polydeoxyribonucleotide (PDRN) injection in a chronic traumatic full-thickness rotator cuff tendon tear (FTRCTT) in a rabbit model. Methods. Rabbits (n=32) were allocated into 4 groups. After a 5 mm sized FTRCTT just proximal to the insertion site on the subscapularis tendon was created by excision, the wound was immediately covered by a silicone tube to prevent natural healing. After 6 weeks, 4 injectants (0.2 mL normal saline, G1-SAL; 0.2 mL PDRN, G2-PDRN; 0.2 mL UCB-MSCs, G3-MSC; and 0.2 mL UCB-MSCs with 0.2 ml PDRN, G4-MSC + PDRN) were injected into the FTRCTT under US guidance. We evaluated gross morphologic changes on all rabbits after sacrifice. Masson’s trichrome, anti-type 1 collagen antibody, bromodeoxyuridine, proliferating cell nuclear antigen, vascular endothelial growth factor, and platelet endothelial cell adhesion molecule stain were performed to evaluate histological changes. Motion analysis was also performed. Results. The gross morphologic mean tendon tear size in G3-MSC and G4-MSC + PDRN was significantly smaller than that in G1-SAL and G2-PDRN (p<0.05). However, there were no significant differences in the tendon tear size between G3-MSC and G4-MSC + PDRN. In G4-MSC + PDRN, newly regenerated collagen type 1 fibers, proliferating cell activity, angiogenesis, walking distance, fast walking time, and mean walking speed were greater than those in the other three groups on histological examination and motion analysis. Conclusions. Coinjection of UCB-MSCs and PDRN was more effective than UCB-MSC injection alone in histological and motion analysis in a rabbit model of chronic traumatic FTRCTT. However, there was no significant difference in gross morphologic change of tendon tear between UCB-MSCs with/without PDRN injection. The results of this study regarding the combination of UCB-MSCs and PDRN are worth additional investigations.
Disturbance Observer-Based Backstepping Control of PMSM for the Mine Traction Electric Locomotive
Authors: Yan Jiande , Wang Hui , Huang Shoudao , Lan Yonghong
Published: May 2018

For the Permanent Magnet Synchronous Motor (PMSM) control system of the Mine Traction Electric Locomotive (MTEL), the fluctuation of the load will lead to the resonance of the velocity of the MTEL. In addition, the speed sensor is easy to be damaged due to the moisture, dust, and vibration. To solve the above problems, a disturbance observer-based (DOB) backstepping control of PMSM for the MTEL is proposed in this paper. First, a full-dimensional Luenberger observer for PMSM is designed and the asymptotically stability of the observer is proved. Next, through the designing of the virtual control input that includes the reconstruction disturbances and using backstepping control strategy, the DOB controller is proposed. The obtained controller can achieve high precision speed tracking and disturbance rejection. Finally, the effectiveness and feasibility of the designed system are verified by Matlab simulation and experiment results.
Anticollision Method of Active Magnetic Guidance Ranging for Cluster Wells
Authors: Dou Xinyu , Liang Huaqing , Liu Yang
Published: May 2018

Conventional adjacent wells range scanning calculations cannot meet the accuracy demands of the anticollision measurement of borehole distances any longer. Current techniques commonly employ electromagnetic detection tools while drilling; this requires putting equipment down adjacent wells to avoid collision risks, which adds more workload and costs and sometimes even affects the normal production of the producing wells. Measuring and tracking adjacent borehole distances while drilling is an essential process that guides the drill bit and effectively avoids collisions with existing wells. This paper proposes an active anticollision method of rotating magnetic ranging based on double symmetrical magnetic sources with opposite magnetic moments. First, the proposed method uses magnetic sources in the drilling well that are built into the probe tube to generate a magnetic field; then, the ferromagnetic casing of the existing well would be magnetized by the abovementioned magnetic field; finally, the magnetization field of the ferromagnetic casing is measured by a triaxial magnetometer built into the probe tube to determine the spacing and position of the existing well. Simultaneously, the calculation models of magnetic flux density around the casing of the existing well and magnetic sources are established, the calculation formulae of the relative distance and position of two adjacent wells are deduced, and a new variable interval section segmentation is proposed based on the Cosine theorem. The simulation results demonstrate that the spacing and position of the existing well are determined based on the magnetic sources’ spacing inside the probe, the magnetic moment of the magnetic sources, the relative permeability of the casing, the diameter of the casing, and the inclination between the drilling well and the existing well. The validity and accuracy of the active magnetization model are confirmed, providing theoretical support for the further development of electromagnetic anticollision devices.
Bifurcation Analysis of a Delayed Worm Propagation Model with Saturated Incidence
Authors: Zhang Zizhen , Wang Yougang , Guerrini Luca
Published: May 2018

This paper is concerned with a delayed SVEIR worm propagation model with saturated incidence. The main objective is to investigate the effect of the time delay on the model. Sufficient conditions for local stability of the positive equilibrium and existence of a Hopf bifurcation are obtained by choosing the time delay as the bifurcation parameter. Particularly, explicit formulas determining direction of the Hopf bifurcation and stability of the bifurcating periodic solutions are derived by using the normal form theory and the center manifold theorem. Numerical simulations for a set of parameter values are carried out to illustrate the analytical results.
Delayed-Onset Seizure in a Mild Quetiapine Overdose: Report of a Case and Review of the Literature
Authors: Chen Jason A. , Unverferth Katherine M. , Cheung Erick H.
Published: May 2018

Among atypical antipsychotics, quetiapine is commonly prescribed and considered to have a favorable side effect and safety profile. Here, we report the case of a patient who developed a generalized tonic-clonic seizure 28 hours following ingestion of 1,400 mg of quetiapine. Review of the literature identifies delayed-onset seizure as a potential complication of quetiapine overdose. Unique to this case, delayed-onset seizures occurred in a patient with a relatively low dose of quetiapine and no obvious toxidrome, suggesting that this reaction may be an important consideration in the management of quetiapine overdose. The pharmacokinetics and pharmacodynamics of quetiapine may explain this unusual phenomenon.
AsymptomaticLeishmaniaInfected Children: A Seroprevalence and Molecular Survey in a Rural Area of Fars Province, Southern Iran
Authors: Layegh Gigloo Akram , Sarkari Bahador , Rezaei Zahra , Hatam Gholam Reza , Davami Mohammad Hassan
Published: May 2018

The current study aimed to evaluate the seroprevalence of visceral leishmaniasis in asymptomatic healthy children in a rural area of Fars province, Southern Iran. Blood samples were taken from 617 asymptomatic healthy children and serum samples along with buffy coat were separated from the blood. The serum samples were assessed for antibodies againstLeishmania infantumby an indirect ELISA and the buffy coats were tested for the presence ofL. infantumDNA by molecular method. Of the 617 recruited children, 297 (48.1%) were female and 317 (51.4%) were male. Anti-Leishmaniaantibodies were detected in 17 (2.8%) of the children. From those 17 seropositive cases, 5 (29.4%) were male and 12 (70.6%) cases were female. Children aged 5–8 years had the highest seroprevalence rate; however, no associations were found between seropositivity toLeishmaniaand gender or age of the children. Moreover,L. infantumDNA was detected in buffy coat of 8 (1.3%) of 617 children. Three of the PCR-positive cases were seropositive whereas 14 of seropositive subjects (82.3%) were PCR-negative. Findings of the current study revealed a considerable subclinical leishmanial infection in children in the studied rural area in the south of Iran. Results of the current study could be used for surveillance, prevention, and control of VL in the area.
mmWave Measurement of RF Reflectors for 5G Green Communications
Authors: Hong Tao , Yao Jin , Liu Cong , Qi Fei
Published: May 2018

In recent years, with the energy consumption and environmental degradation, science and technology embarked on a path of sustainable development. In this situation, 5G green communication system has been widely used. This paper introduces the application of RF reflectors to 5G mmWave, where line‐of‐sight (LoS) blockage is a major hindrance for the coverage. In particular, we investigate the lab measurement of RF reflectors, which is a critical step from the theory to the practice. Furthermore, through the lab measurement, a 3D near‐field range migration (RM) imaging algorithm for MIMO array configuration is proposed, and the sampling scheme is improved to save the computation time while providing high‐quality images.
The Diverse Mechanisms of miRNAs and lncRNAs in the Maintenance of Liver Cancer Stem Cells
Authors: Zhao Jing , Fu Yan , Wu Jing , Li Juan , Huang Guangjian , Qin Lunxiu
Published: May 2018

Liver cancer is the second leading cause of cancer-related death worldwide. The high frequency of recurrence and metastasis is the main reason for poor prognosis. Liver cancer stem cells (CSCs) have unlimited self-renewal, differentiation, and tumor-regenerating capacities. The maintenance of CSCs may account for the refractory features of liver cancer. Despite extensive investigations, the underlying regulatory mechanisms of liver CSCs remain elusive. miRNA and lncRNA, two major classes of the ncRNA family, can exert important roles in various biological processes, and their diverse regulatory mechanisms in CSC maintenance have acquired increasing attention. However, to the best of our knowledge, there is a lack of reviews summarizing these findings. Therefore, we systematically recapitulated the latest studies on miRNAs and lncRNAs in sustaining liver CSCs. Moreover, we highlighted the potential clinical application of these dysregulated ncRNAs as novel diagnostic and prognostic biomarkers and therapeutic targets. This review not only sheds new light to fully understand liver CSCs but also provides valuable clues on targeting ncRNAs to block or eradicate CSCs in cancer treatment.
Abnormal Liver Function Induced by Space-Occupying Lesions Is Associated with Unfavorable Oncologic Outcome in Patients with Colorectal Cancer Liver Metastases
Authors: Jiang Zheng , Li Chunxiang , Zhao Zhixun , Liu Zheng , Guan Xu , Yang Ming , Li Xiaofu , Yuan Dawei , Qiu Songbo , Wang Xishan
Published: May 2018

An early prediction of prognosis for patients with colorectal liver metastasis (CRLM) may help us determine treatment strategies. Liver function reflects the effect of the overall metastatic burden. We investigated the prognostic value of liver function in CRLM patients. In our study, patients with abnormal LFTs (liver function tests) had a poorer prognosis than did those with normal LFTs (P<0.05). A multivariate analysis revealed that LFTs was an independent prognostic factor for CRLM. For those patients with abnormal LFTs, novel prognostic contour maps were generated using LFTs, and no positive correlation exists between the values of survival duration and abnormal LFTs. Additionally, the MTVR (metastatic tumor volume ratio) was measured directly by magnetic resonance imaging and was shown to be highly correlated to LFTs by a Pearson correlation analysis. A multivariate logistic regression analysis also demonstrated that the MTVR and hepatectomy were independently predictive of abnormal LFTs. The space-occupying effect of metastatic lesions can cause abnormal LFTs, resulting in a poor prognosis. Biochemical analyses of LFTs at the initial diagnosis of CRLM enable the stratification of patients into low- and high-risk groups; it may help clinicians determine promising treatment strategies.
Design and Analysis of CFD Experiments for the Development of Bulk-Flow Model for Staggered Labyrinth Seal
Authors: Cangioli Filippo , Pennacchi Paolo , Nettis Leonardo , Ciuchicchi Lorenzo
Published: May 2018

Nowadays, bulk-flow models are the most time-efficient approaches to estimate the rotor dynamic coefficients of labyrinth seals. Dealing with the one-control volume bulk-flow model developed by Iwatsubo and improved by Childs, the “leakage correlation” allows the leakage mass-flow rate to be estimated, which directly affects the calculation of the rotor dynamic coefficients. This paper aims at filling the lack of the numerical modelling for staggered labyrinth seals: a one-control volume bulk-flow model has been developed and, furthermore, a new leakage correlation has been defined using CFD analysis. Design and analysis of computer experiments have been performed to investigate the leakage mass-flow rate, static pressure, circumferential velocity, and temperature distribution along the seal cavities. Four design factors have been chosen, which are the geometry, pressure drop, inlet preswirl, and rotor peripheral speed. Finally, dynamic forces, estimated by the bulk-flow model, are compared with experimental measurements available in the literature.
Multiparametric MRI and Computational Modelling in the Assessment of Human Articular Cartilage Properties: A Comprehensive Approach
Authors: Thüring J. , Linka K. , Itskov M. , Knobe M. , Hitpaß L. , Kuhl C. , Truhn D. , Nebelung S.
Published: May 2018

Quantitative magnetic resonance imaging (qMRI) is a promising approach to detect early cartilage degeneration. However, there is no consensus on which cartilage component contributes to the tissue’s qMRI signal properties. T1, T1ρ, and T2⁎ maps of cartilage samples (n=8) were generated on a clinical 3.0-T MRI system. All samples underwent histological assessment to ensure structural integrity. For cross-referencing, a discretized numerical model capturing distinct compositional and structural tissue properties, that is, fluid fraction (FF), proteoglycan (PG) and collagen (CO) content and collagen fiber orientation (CFO), was implemented. In a pixel-wise and region-specific manner (central versus peripheral region), qMRI parameter values and modelled tissue parameters were correlated and quantified in terms of Spearman’s correlation coefficient ρs. Significant correlations were found between modelled compositional parameters and T1 and T2⁎, in particular in the central region (T1: ρs≥0.7 [FF, CFO], ρs≤-0.8 [CO, PG]; T2⁎: ρs≥0.67 [FF, CFO], ρs≤-0.71 [CO, PG]). For T1ρ, correlations were considerably weaker and fewer (0.16≤ρs≤-0.15). QMRI parameters are characterized in their biophysical properties and their sensitivity and specificity profiles in a basic scientific context. Although none of these is specific towards any particular cartilage constituent, T1 and T2⁎ reflect actual tissue compositional features more closely than T1ρ.
Thoracic Empyema as Rare Complication of an Appendicular Mass: A Case Study and Review of the Literature
Authors: Vasquez-Rios George , Calixto-Aguilar Lesly , Pajuelo Richard , Alarcon Wilder
Published: May 2018

Introduction. Thoracic empyema is an infrequent complication of appendicitis that has rarely been reported in the literature. Case Presentation and Review of the Literature. The case of a 11-year-old boy who was admitted for medical management of an appendicular mass is presented. His clinical course was complicated by the development of an appendicular abscess and an extensive right-sided empyema. A comprehensive review of the literature was conducted including the most representative cases. The data were collected and analyzed by two independent investigators. Ten cases were found. Most patients were young individuals (mean age: 25.1 years; male : female ratio: 0.5). Risk factors for thoracic empyema included pregnancy (10%) and age (60%). The most frequent organisms isolated were Escherichia coli, Bacteroides spp., and Klebsiella spp. The survival rate was 100%. Conclusion. Thoracic empyema should be considered a potential cause of respiratory distress in patients with appendicitis. Furthermore, the abdomen should be carefully evaluated as a source of infection in patients with thoracic empyema without an underlying lung disease.
A Midgut Digestive Phospholipase A2in Larval Mosquitoes,Aedes albopictusandCulex quinquefasciatus
Authors: Abdul Rahim Nor Aliza , Othman Marlini , Sabri Muna , Stanley David W.
Published: May 2018

Phospholipase A2(PLA2) is a secretory digestive enzyme that hydrolyzes ester bond atsn-2position of dietary phospholipids, creating free fatty acid and lysophospholipid. The free fatty acids (arachidonic acid) are absorbed into midgut cells.Aedes albopictusandCulex quinquefasciatusdigestive PLA2was characterized using a microplate PLA2assay. The enzyme showed substantial activities at 6 and 8 μg/μl of protein concentration with optimal activity at 20 and 25 μg/μl of substrate concentration inAedes albopictusandCulex quinquefasciatus, respectively. PLA2activity from both mosquitoes increased in a linear function up to 1 hour of the reaction time. Both enzymes were sensitive to pH and temperature. PLA2showed higher enzyme activities in pH 8.0 and pH 9.0 fromAedes albopictusandCulex quinquefasciatus, respectively, at 40°C of incubation. The PLA2activity decreased in the presence of 5 mM(Aedes albopictus)and 0.5 mM(Culex quinquefasciatus)site specific PLA2inhibitor, oleyloxyethylphosphorylcholine. Based on the migration pattern of the partially purified PLA2on SDS-PAGE, the protein mass of PLA2is approximately 20–25 kDa for both mosquitoes. The information on PLA2properties derived from this study may facilitate in devising mosquitoes control strategies especially in the development of inhibitors targeting the enzyme active site.
HP1γ Promotes Lung Adenocarcinoma by Downregulating the Transcription-Repressive Regulators NCOR2 and ZBTB7A
Authors: Alam Hunain , Li Na , Dhar Shilpa S. , Wu Sarah J. , Lv Jie , Chen Kaifu , Flores Elsa R. , Baseler Laura , Lee Min Gyu
Published: May 2018

Lung adenocarcinoma is a major form of lung cancer, which is the leading cause of cancer death. Histone methylation reader proteins mediate the effect of histone methylation, a hallmark of epigenetic and transcriptional regulation of gene expression. However, their roles in lung adenocarcinoma are poorly understood. Here, our bioinformatic screening and analysis in search of a lung adenocarcinoma–promoting histone methylation reader protein show that heterochromatin protein 1γ (HP1γ; also called CBX3) is among the most frequently overexpressed and amplified histone reader proteins in human lung adenocarcinoma, and that high HP1γ mRNA levels are associated with poor prognosis in patients with lung adenocarcinoma. In vivo depletion of HP1γ reduced K-RasG12D–driven lung adenocarcinoma and lengthened survival of mice bearing K-RasG12D–induced lung adenocarcinoma. HP1γ and its binding activity to methylated histone H3 lysine 9 were required for the proliferation, colony formation, and migration of lung adenocarcinoma cells. HP1γ directly repressed expression of the transcription-repressive regulators NCOR2 and ZBTB7A. Knockdown of NCOR2 or ZBTB7A significantly restored defects in proliferation, colony formation, and migration in HP1γ-depleted lung adenocarcinoma cells. Low NCOR2 or ZBTB7A mRNA levels were associated with poor prognosis in patients with lung adenocarcinoma and correlated with high HP1γ mRNA levels in lung adenocarcinoma samples. NCOR2 and ZBTB7A downregulated expression of tumor-promoting factors such as ELK1 and AXL, respectively. These findings highlight the importance of HP1γ and its reader activity in lung adenocarcinoma tumorigenesis and reveal a unique lung adenocarcinoma–promoting mechanism in which HP1γ downregulates NCOR2 and ZBTB7A to enhance expression of protumorigenic genes.

Significance: Direct epigenetic repression of the transcription-repressive regulators NCOR2 and ZBTB7A by the histone reader protein HP1γ leads to activation of protumorigenic genes in lung adenocarcinoma. Cancer Res; 78(14); 3834–48. ©2018 AACR.
Phase I Study of CC-486 Alone and in Combination with Carboplatin or nab-Paclitaxel in Patients with Relapsed or Refractory Solid Tumors
Authors: Von Hoff Daniel D. , Rasco Drew W. , Heath Elisabeth I. , Munster Pamela N. , Schellens Jan H.M. , Isambert Nicolas , Tourneau Christophe Le , O'Neil Bert , Mathijssen Ron H.J. , Lopez-Martin Jose A. , Edenfield W. Jeff , Martin Miguel , LoRusso Patricia M. , Bray Gordon L. , DiMartino Jorge , Nguyen Aaron , Liu Kejian , Laille Eric , Bendell Johanna C.
Published: May 2018

Purpose: This large two-part, three-arm phase I study examined the safety and tolerability of CC-486 (an oral formulation of azacitidine, a hypomethylating agent) alone or in combination with the cytotoxic agents, carboplatin or nab-paclitaxel, in patients with advanced unresectable solid tumors.

Patients and Methods: Part 1 (n = 57) was a dose escalation of CC-486 alone (arm C) or with carboplatin (arm A) or nab-paclitaxel (arm B). The primary endpoint was safety, MTD, and recommended part 2 dose (RP2D) of CC-486. In part 2 (n = 112), the primary endpoint was the safety and tolerability of CC-486 administered at the RP2D for each treatment arm, in tumor-specific expansion cohorts. Secondary endpoints included pharmacokinetics, pharmacodynamics, and antitumor activity of CC-486.

Results: At pharmacologically active doses CC-486 in combination with carboplatin or nab-paclitaxel had a tolerable safety profile and no drug–drug interactions. The CC-486 RP2D was determined as 300 mg (every day, days 1–14/21) in combination with carboplatin (arm A) or as monotherapy (arm C); and 200 mg in the same dosing regimen in combination with nab-paclitaxel (arm B). Albeit limited by the small sample size, CC-486 monotherapy resulted in partial responses (three/eight) and stable disease (four/eight) in patients with nasopharyngeal cancer. Three of the stable disease responses lasted more than 150 days.

Conclusions: CC-486 is well tolerated alone or in combination with carboplatin or nab-paclitaxel. Exploratory analyses suggest clinical activity of CC-486 monotherapy in nasopharyngeal cancer and provided the basis for an ongoing phase II clinical trial (ClinicalTrials.gov identifier: NCT02269943). Clin Cancer Res; 24(17); 4072–80. ©2018 AACR.
Abstract A06: Automated, high-throughput 3D desorption electrospray ionization (DESI) mass spectrometry imaging of a xenograft model of glioblastoma
Authors: Henderson Fiona , Jones Emrys , Denbeigh Joanna , Christie Lidan , Batey Michael A. , Claude Emmanuelle , Williams Kaye J. , McMahon Adam
Published: May 2018

Glioblastomas are a highly aggressive brain tumor, which are commonly resistant to chemotherapy and radiotherapy. The heterogeneity of these tumors can cause major problems for diagnosis and therapy. It is therefore important to study these local variations in glioblastoma metabolism, in order to understand tumor development and to guide treatment. Desorption electrospray ionization mass spectrometry (DESI MS) imaging is a technique that can image hundreds of molecules in a 2D tissue section in a single scan, making it an ideal tool for imaging heterogeneity in tumors. Here, 3D DESI-MS imaging has been implemented to reveal lipid heterogeneity in a whole xenograft glioblastoma. In addition, immunofluorescence staining has been used to elucidate the role of hypoxia in lipid heterogeneity.

Fifteen sections were taken from a xenograft glioblastoma at 120-um increments for DESI-MS imaging. DESI-MS imaging was carried out in both negative and positive ion mode, using the spatial resolution of 120um, to allow even-sized voxels. An automatic slide loader was used to allow high-throughput imaging. Recently written software at Waters, UK was used to automatically reconstruct a 3D image from the 2D DESI-MS images. Serial sections were used for immunofluorescence staining of carbonic anhydrase-9 (a marker for hypoxia). Sections also underwent H&E staining.

High-throughput 3D DESI-MS imaging has been carried out to reveal lipid heterogeneity in a xenograft glioblastoma. Here, 3D DESI-MS imaging reveals segmentation of the tumor based on local lipid expression, which correlates with the histologic mapping of normoxia, hypoxia, and necrosis. Hypoxia is a key contributor to tumor heterogeneity and, importantly, is associated with aggressive tumor development. This work highlights that lipids are playing an important role in glioblastoma heterogeneity. Furthermore, DESI-MS imaging can be used for 3D lipid imaging in an automated fashion, to reveal heterogeneity that is not apparent in H&E stains alone.

Citation Format: Fiona Henderson, Emrys Jones, Joanna Denbeigh, Lidan Christie, Michael A. Batey, Emmanuelle Claude, Kaye J. Williams, Adam McMahon. Automated, high-throughput 3D desorption electrospray ionization (DESI) mass spectrometry imaging of a xenograft model of glioblastoma [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr A06.
Abstract A37: SB insertional mutagenesis identifies new metastasis-promoting tumor suppressor genes in pancreatic cancer
Authors: Maurin Michelle , Jones Devin J. , Black Mik A. , Newberg Justin Y. , Jenkins Nancy A. , Copeland Neal G. , Mann Karen M.
Published: May 2018

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease with poor patient outcome. While acquired oncogenic activation of KRAS is an initiating event, disease progression requires functional perturbation of additional genes and cellular pathways. Identifying key molecular events that cooperate with oncogenic KRAS in human tumors to drive disease progression is a challenge due in part to the high degree of inter- and intratumor heterogeneity in PDAC genomes. We have taken a comparative genomics approach to identify progression drivers using a mouse model of metastatic PDAC driven by Sleeping Beauty (SB) insertional mutagenesis in the context of oncogenic Kras. Statistical enrichment analysis of SB insertions defined hundreds of cooperating tumor-suppressor genes in SB PDAC tumors. We hypothesized that recurrently mutated TSGs in pancreatic tumors drive metastatic disease. Enrichment analysis of high-read depth insertions from SB PDAC tumors defined 48 drivers predicted to contribute to disease progression. Thirty-two of these genes were statistically enriched in a population-based analysis of SB insertions in metastases isolated from a subset of the animals from the primary cohort. We demonstrated significant increases in primary tumor burden and metastatic spread by single-gene knockdown of novel TSGs TCF12, FNDC3B, or RBFOX2 in orthotopic human PDAC mouse models. TCF12 encodes a basic Helix-loop-helix (bHLH) transcription factor that partners with other bHLH transcription factors in different cellular contexts, including TWIST, a transcription factor involved in epithelial-to-mesenchymal transition (EMT); PTF1A, a pancreas-specific transcription factor with essential roles in pancreas development and cancer; and SMAD3, a TGFβ-related transcription factor involved in cellular migration. TCF12 resides in a chromosomal region (15q21) frequently lost in pancreatic cancer, and decreased TCF12 expression is associated with poor patient prognosis. Using human PDAC expression data from ICGC, we identified 209 genes that exhibit coregulated gene expression with TCF12. A subset of these genes function in Wnt or TGF-Beta signaling pathways and show consistent decreases in expression upon TCF12 knockdown in orthotopic tumors. Ongoing experiments aim to define the TCF12 transcriptional targets involved in metastatic progression.

Citation Format: Michelle Maurin, Devin J. Jones, Mik A. Black, Justin Y. Newberg, Nancy A. Jenkins, Neal G. Copeland, Karen M. Mann. SB insertional mutagenesis identifies new metastasis-promoting tumor suppressor genes in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr A37.
Abstract B04: Activating K-RasA146T mutations induce Mapk-dependent hyperproliferation in the intestinal epithelium
Authors: Poulin Emily , Gierut Jessica , Haigis Kevin
Published: May 2018

Ras is the most commonly mutated oncogene in human cancer, and is highly mutated in pancreatic, lung, and colorectal cancer. The most commonly reported canonical activating point mutations occur in codons 12, 13, and 61. Colorectal cancer, in particular, harbors a number of noncanonical K-Ras mutations, including mutations at codon 146, which occur in ~4% of patients. To understand the biologic effects of K-RasA146T expression in the intestinal epithelium and other tissues, we engineered a conditional Cre recombinase-dependent mutant allele (K-RasLSL-A146T), expressed from the endogenous KRas locus. We crossed K-RasLSL-A146T mice to Fabpl-Cre mice, which express Cre recombinase in the colonic and distal small intestinal epithelium, and compared the phenotype of Fabpl-Cre; K-RasLSL-A146T/+ mice to that of Fabpl-Cre; K-RasLSL-G12D/+ mice. Compared to K-RasG12D, expression of K-RasA146T results in a mild hyperplastic and hyperproliferative phenotype, while expression of K-RasG12D causes drastic hyperplasia and hyperproliferation. Additionally, we found that K-RasA146T expression activates Mapk signaling and that K-RasA146T-induced hyperproliferation is Mapk-dependent. Interestingly, unlike Fabpl-Cre; K-RasLSL-G12D mice, which lack Paneth cells in the small intestine, Fabpl-Cre; K-RasLSL-A146T/+ mice have intact Paneth cells. Finally, we found that although K-RasG12D expression in the pancreas causes neoplastic transformation, K-RasA146T expression has no detectable effect on pancreatic homeostasis, even after one year. Together, our results suggest that compared to the canonical K-RasG12D mutation, activating K-RasA146T mutations have a similar but milder effect on colonic homeostasis. Additionally, consistent with human data, we found that K-RasA146T mutations have tissue-specific effects on neoplastic transformation.

Citation Format: Emily Poulin, Jessica Gierut, Kevin Haigis. Activating K-RasA146T mutations induce Mapk-dependent hyperproliferation in the intestinal epithelium [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr B04.
Abstract B12: The importance of the RASA1/R-Ras/Ral-A signaling axis in melanoma tumorigenesis
Authors: Hill Kristen S. , Wang Xue , Roberts Evan R. , Kim Youngchul , Messina Jane , Kim Minjung
Published: May 2018

The Ras family of small GTP-binding proteins is frequently activated by mutations, including NRAS (20%), KRAS (2%), and HRAS (1%), in melanoma. In addition to mutations, Ras isoforms can also be activated by the inactivation of Ras GTPase activating proteins (RasGAPs), such as NF1, RASA1, and RASA2. In our recent study, we observed that the inactivation of RASA1 (RAS p21 protein activator 1, also called p120RasGAP) suppressed melanoma via its RasGAP activity toward the R-Ras (related RAS viral (r-ras) oncogene homolog) isoform. We hypothesized that, although not mutated, R-Ras is activated in melanoma through the inactivation of RasGAPs and that RasGAP/R-Ras pathway activation cooperates with BRAF activation in melanoma tumorigenesis.

In this study, we addressed the importance of R-Ras, a previously less-appreciated member of the Ras family, in melanoma tumorigenesis and investigated the molecular mechanisms underlying R-Ras signaling in BRAF mutant melanoma. We observed frequent activation of R-Ras in BRAF mutant human melanoma cell lines. In addition, RNAi-mediated reduced expression of R-Ras suppressed anchorage-independent colony growth and tumor growth. Moreover, among the three major RAS effector pathways, reduced R-Ras expression suppressed Ral-A activation, which may explain the mechanism of Ral-A activation in BRAF mutant melanoma. Interestingly, anchorage-independent growth driven by RASA1 inactivation and subsequent R-Ras activation was suppressed by both genetic (siRNA targeting Ral-A) and pharmacologic (Ral inhibitor BQU57) inhibition of Ral-A. To further investigate the impact of RASA1 loss, and thus R-Ras activation, on BRAF mutant melanoma development in vivo, we generated a RASA1 L/L; BRAF CA/CA; Tyr-CreERT2 mouse model in which treatment with 4OHT results in the expression of constitutively activated mutant BRAF and the deletion of RASA1 in melanocytic lineage cells. Preliminary analysis shows hyperpigmentation of the ear, tail, and foot pad in RASA1 L/L BRAF CA/CA mice compared to RASA1 +/+ BRAF CA/CA littermates and the development of melanoma in RASA1 mutant mice. This study demonstrates the importance of the RASA1/R-Ras/Ral-A signaling pathway in BRAF mutant melanoma and supports the possible combinatorial treatment strategy targeting both the BRAF/MAPK and Ral signaling pathways.

Citation Format: Kristen S. Hill, Xue Wang, Evan R. Roberts, Youngchul Kim, Jane Messina, Minjung Kim. The importance of the RASA1/R-Ras/Ral-A signaling axis in melanoma tumorigenesis [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr B12.
Abstract B35: An innovative in vivo model of metastasizing prostate cancer using orthotopic xenografts
Authors: Linxweiler Johannes , Körbel Christina , Müller Andreas , Hammer Markus , Stöckle Michael , Junker Kerstin , Menger Michael D.
Published: May 2018

Introduction: In this study, we aimed to develop a versatile in vivo model of prostate cancer using orthotopic xenografts, which adequately represents intraprostatic tumor growth as well as the natural routes of metastatic spread.

Materials and Methods: 5x105 VCaP-, LuCaP136-, and LuCaP147 cells were injected into the prostate of male CB17-SCID mice (n=8 for each cell line; VCaP cultured as monolayer, LuCaP136 and LuCaP147 as three-dimensional spheroid culture). During 12 weeks of follow-up, orthotopic tumor growth and the development of metastases was monitored by repetitive serum-PSA measurements and imaging studies (ultrasonography, CT, MRI). At autopsy, primary tumors and metastases were harvested and examined by conventional histology (H&E) and immunohistochemistry (CK5, CK8, AMACR, AR, Ki67, ERG, PSA). From the results of the imaging studies and PSA measurements, tumor volume doubling time, tumor-specific growth rate, and PSA-density were calculated for each cell line.

Results: All 24 mice developed orthotopic tumors, whose growth could be reliably monitored by ultrasonography, CT, MRI, and serum-PSA measurements. 4 animals died during follow-up (1 in the VCaP group, 1 in the LuCaP136 group, 2 in the LuCaP147 group). Mean PSA-density was 433.9 ng/ml per ml tumor in the VCaP group, 6.5 ng/ml per ml tumor in the LuCaP136 group, and 11.2 ng/ml per ml tumor in the LuCaP147 group. Tumor-specific growth rate and tumor volume doubling time were 3.87% per day and 21.24 days in the VCaP group, 3.11% and 27.57 days in the LuCaP136 group, and 4.47% and 16.2 days in the LuCaP147 group, respectively. In up to 100% of animals, lymph node metastases could be detected after 12 weeks (5/7 in the VCaP group, 6/7 in the LuCaP136 group, 6/6 in the LuCaP147 group). These could also be visualized by ultrasonography and MRI. Immunohistochemistry showed positive CK8, AR, and AMACR as well as negative CK5 reactions in all tumors. ERG-straining was positive in VCaP and negative in both LuCaP tumors, Ki67 proliferation indices were >90% in all groups.

Conclusions: By using different monolayer as well as 3D spheroid cell cultures in an orthotopic xenograft model, we could establish an innovative, versatile in vivo model of prostate cancer, which enables the study of both intraprostatic tumor growth as well as metastatic spread to regional lymph nodes.

Citation Format: Johannes Linxweiler, Christina Körbel, Andreas Müller, Markus Hammer, Michael Stöckle, Kerstin Junker, Michael D. Menger. An innovative in vivo model of metastasizing prostate cancer using orthotopic xenografts [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr B35.
Abstract B37: RNAi and CRISPR/Cas9-based in vivo models for drug discovery
Authors: Premsrirut Prem K. , Wang Chia-Lin , Yang Yu-ting , Pelossof Rafii , Leslie Christina , Fellmann Christof , Dow Lukas , Zuber Johannes , Lowe Scott
Published: May 2018

With the advent of RNAi and more recently CRISPR/Cas9 technologies, the speed and precision by which genetically engineered mouse models of cancer can be created is unprecedented. Having previously engineered a miRE scaffold for enhanced shRNA processing and now with the introduction of a powerful new SplashRNA algorithm for accurate shRNA prediction, we have brought RNAi technology to its peak by increasing potency and reducing off-target effects, such that it can be effectively exploited to preclinically mimic drug therapy and even combination therapy not only in vitro but also in live mice. Here, we take advantage of Cas9-expressing mice and demonstrate that in situ delivery of sgRNAs can lead to somatic mutagenesis to promote rapid tumorigenesis in mice. By combining this approach with inducible and reversible RNAi-mediated gene silencing to mimic drug therapy in the same mice, we now have an advanced platform to perform target validation and toxicity assessment of novel candidate targets in vivo. Here, we showcase how synergizing our RNAi and CRISPR/Cas9 genetic toolbox will help facilitate cancer drug discovery research and increase our confidence in predicting drug responses in humans into a new era.

Citation Format: Prem K. Premsrirut, Chia-Lin Wang, Yu-ting Yang, Rafii Pelossof, Christina Leslie, Christof Fellmann, Lukas Dow, Johannes Zuber, Scott Lowe. RNAi and CRISPR/Cas9-based in vivo models for drug discovery [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr B37.
Abstract IA07: Deconstructing p53 pathways in tumor suppression
Authors: Mello Stephano Spano , Bieging-Rolett Kathryn , Kaiser Alyssa , Valente Elizabeth Joy , Raj Nitin , McClendon Jacob , Flowers Brittany Maria , Morgens David Warren , Bassik Michael Cory , Attardi Laura Donatella
Published: May 2018

The p53 transcription factor is a critical tumor suppressor in humans and mice. Despite this essential function, the molecular pathways through which p53 acts in tumor suppression remain enigmatic. To define the transcriptional programs through which p53 suppresses carcinogenesis, we have taken combined mouse genetic and genomic approaches. We previously generated a panel of p53 knock-in mouse strains expressing mutants in the first (p5325,26), second (p5353,54), or both (p5325,26,53,54) of two amino-terminal transcriptional activation domains (TADs). In terms of transcriptional activity, we have discovered that p5325,26 is severely impaired for transactivation of the majority of canonical p53 target genes (e.g. p21, Puma, Noxa), but retains the ability to activate a set of primarily novel p53 target genes, while p5325,26,53,54 lacks transactivation activity altogether. The p5353,54 mutant, in contrast, is uncompromised for transactivation of p53 target genes. The p5325,26,53,54 mutant is completely defective in tumor suppression, underscoring the importance of transcriptional activation for p53-mediated tumor suppression. Intriguingly, the p5325,26 mutant retains full activity in suppressing a variety of cancers, indicating that efficient transactivation of most canonical p53 target genes is dispensable for tumor suppression. As p5325,26 activates only a subset of p53-inducible genes, yet retains tumor-suppressor activity, it has helped pinpoint a small set of novel, direct p53-inducible tumor suppression-associated target genes (TSAGs) whose functions we are currently interrogating through genetic screens. Additionally, we have made the surprising discovery that the p5353,54 mutant suppresses pancreatic cancer more efficiently than wild-type p53, and that this capacity correlates with the ability of p5353,54 to hyperactivate a subset of p53 target genes. Indeed, our analysis of these genes has uncovered Ptpn14, a direct p53 target gene critical for mediating p53 function in suppressing pancreatic cancer cell growth. Ptpn14 encodes a protein tyrosine phosphatase that negatively regulates the oncoprotein Yap in both human and mouse cells. These studies thus reveal a p53-Ptpn14-Yap axis in pancreatic cancer. Together, these strategies will help to elaborate the transcriptional networks fundamental for p53 function in tumor suppression.

Citation Format: Stephano Spano Mello, Kathryn Bieging-Rolett, Alyssa Kaiser, Elizabeth Joy Valente, Nitin Raj, Jacob McClendon, Brittany Maria Flowers, David Warren Morgens, Michael Cory Bassik, Laura Donatella Attardi. Deconstructing p53 pathways in tumor suppression [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr IA07.