bluuebunny/crossref_metadata_2025 huggingface dataset:
SEISMIC RISK ASSESSMENT AND MITIGATION FOR THE EXISTING LIFELINE
Authors: IMAI T. , WADA S. , KOIKE T.
Published: January 2011

In order to keep the existing lifeline network system at a favorable seismic performance level, it is necessary to carry out retrofitting activities. This study proposes a seismic risk assessment method for the existing deteriorated lifeline network system based on the probability of system performance failure. Numerical simulations are carried out for the existing water distribution network system for several seismic investment strategies to support the decision making of seismic disaster mitigation planning. Effective planning of seismic retrofitting activities and disaster mitigation for the existing lifeline system can be realized using the newly developed assessment method.
Template to improve glycemic control without reducing adiposity or dietary fat
Authors: Krishnapuram R. , Dhurandhar E. J. , Dubuisson O. , Kirk-Ballard H. , Bajpeyi S. , Butte N. , Sothern M. S. , Larsen-Meyer E. , Chalew S. , Bennett B. , Gupta A. K. , Greenway F. L. , Johnson W. , Brashear M. , Reinhart G. , Rankinen T. , Bouchard C. , Cefalu W. T. , Ye J. , Javier R. , Zuberi A. , Dhurandhar N. V.
Published: January 2011

Drugs that improve chronic hyperglycemia independently of insulin signaling or reduction of adiposity or dietary fat intake may be highly desirable. Ad36, a human adenovirus, promotes glucose uptake in vitro independently of adiposity or proximal insulin signaling. We tested the ability of Ad36 to improve glycemic control in vivo and determined if the natural Ad36 infection in humans is associated with better glycemic control. C57BL/6J mice fed a chow diet or made diabetic with a high-fat (HF) diet were mock infected or infected with Ad36 or adenovirus Ad2 as a control for infection. Postinfection (pi), systemic glycemic control, hepatic lipid content, and cell signaling in tissues pertinent to glucose metabolism were determined. Next, sera of 1,507 adults and children were screened for Ad36 antibodies as an indicator of past natural infection. In chow-fed mice, Ad36 significantly improved glycemic control for 12 wk pi. In HF-fed mice, Ad36 improved glycemic control and hepatic steatosis up to 20 wk pi. In adipose tissue (AT), skeletal muscle (SM), and liver, Ad36 upregulated distal insulin signaling without recruiting the proximal insulin signaling. Cell signaling suggested that Ad36 increases AT and SM glucose uptake and reduces hepatic glucose release. In humans, Ad36 infection predicted better glycemic control and lower hepatic lipid content independently of age, sex, or adiposity. We conclude that Ad36 offers a novel tool to understand the pathways to improve hyperglycemia and hepatic steatosis independently of proximal insulin signaling, and despite a HF diet. This metabolic engineering by Ad36 appears relevant to humans for developing more practical and effective antidiabetic approaches.
Antiapoptotic effects of GLP-1 in murine HL-1 cardiomyocytes
Authors: Ravassa Susana , Zudaire Amaia , Carr Richard D. , Díez Javier
Published: January 2011

Activation of apoptosis contributes to cardiomyocyte dysfunction and death in diabetic cardiomyopathy. The peptide glucagon-like peptide-1 (GLP-1), a hormone that is the basis of emerging therapy for type 2 diabetic patients, has cytoprotective actions in different cellular models. We investigated whether GLP-1 inhibits apoptosis in HL-1 cardiomyocytes stimulated with staurosporine, palmitate, and ceramide. Studies were performed in HL-1 cardiomyocytes. Apoptosis was induced by incubating HL-1 cells with staurosporine (175 nM), palmitate (135 μM), or ceramide (15 μM) for 24 h. In staurosporine-stimulated HL-1 cardiomyocytes, phosphatidylserine exposure, Bax-to-Bcl-2 ratio, Bad phosphorylation (Ser136), BNIP3 expression, mitochondrial membrane depolarization, cytochrome c release, caspase-3 activation, DNA fragmentation, and mammalian target of rapamycin (mTOR)/p70S6K phosphorylation (Ser2448 and Thr389, respectively) were assessed. Apoptotic hallmarks were also measured in the absence or presence of low (5 mM) and high (10 mM) concentrations of glucose. In addition, phosphatidylserine exposure and DNA fragmentation were analyzed in palmitate- and ceramide-stimulated cells. Staurosporine increased apoptosis in HL-1 cardiomyocytes. GLP-1 (100 nM) partially inhibited staurosporine-induced mitochondrial membrane depolarization and completely blocked the rest of the staurosporine-induced apoptotic changes. This cytoprotective effect was mainly mediated by phosphatidylinositol 3-kinase (PI3K) and partially dependent on ERK1/2. Increasing concentrations of glucose did not influence GLP-1-induced protection against staurosporine. Furthermore, GLP-1 inhibited palmitate- and ceramide-induced phosphatidylserine exposure and DNA fragmentation. Incretin GLP-1 protects HL-1 cardiomyocytes against activation of apoptosis. This cytoprotective ability is mediated mainly by the PI3K pathway and partially by the ERK1/2 pathway and seems to be glucose independent. It is proposed that therapies based on GLP-1 may contribute to prevent cardiomyocyte apoptosis.
Electromechanical coupling between the atria and mitral valve
Authors: Swanson Julia C. , Krishnamurthy Gaurav , Kvitting John-Peder Escobar , Craig Miller D. , Ingels Neil B.
Published: January 2011

Anterior leaflet (AL) stiffening during isovolumic contraction (IVC) may aid mitral valve closure. We tested the hypothesis that AL stiffening requires atrial depolarization. Ten sheep had radioopaque-marker arrays implanted in the left ventricle, mitral annulus, AL, and papillary muscle tips. Four-dimensional marker coordinates ( x, y, z, and t) were obtained from biplane videofluoroscopy at baseline (control, CTRL) and during basal interventricular-septal pacing (no atrial contraction, NAC; 110–117 beats/min) to generate ventricular depolarization not preceded by atrial depolarization. Circumferential and radial stiffness values, reflecting force generation in three leaflet regions (annular, belly, and free-edge), were obtained from finite-element analysis of AL displacements in response to transleaflet pressure changes during both IVC and isovolumic relaxation (IVR). In CTRL, IVC circumferential and radial stiffness was 46 ± 6% greater than IVR stiffness in all regions ( P < 0.001). In NAC, AL annular IVC stiffness decreased by 25% ( P = 0.004) in the circumferential and 31% ( P = 0.005) in the radial directions relative to CTRL, without affecting edge stiffness. Thus AL annular stiffening during IVC was abolished when atrial depolarization did not precede ventricular systole, in support of the hypothesis. The likely mechanism underlying AL annular stiffening during IVC is contraction of cardiac muscle that extends into the leaflet and requires atrial excitation. The AL edge has no cardiac muscle, and thus IVC AL edge stiffness was not affected by loss of atrial depolarization. These findings suggest one reason why heart block, atrial dysrhythmias, or ventricular pacing may be accompanied by mitral regurgitation or may worsen regurgitation when already present.
Effect of clonidine on cardiac baroreflex delay in humans and rats
Authors: Cividjian Andrei , Toader Emil , Wesseling Karel H. , Karemaker John M. , McAllen Robin , Quintin Luc
Published: January 2011

The delay τ between rising systolic blood pressure (SBP) and baroreflex bradycardia has been found to increase when vagal tone is low. The α2-agonist clonidine increases cardiac vagal tone, and this study tested how it affects τ. In eight conscious supine human volunteers clonidine (6 μg/kg po) reduced τ, assessed both by cross correlation baroreflex sensitivity and sequence methods (both P < 0.05). Experiments on urethane-anaesthetized rats reproduced the phenomenon and investigated the underlying mechanism. Heart rate (HR) responses to increasing SBP produced with an arterial balloon catheter showed reduced τ ( P < 0.05) after clonidine (100 μg/kg iv). The central latency of the reflex was unaltered, however, as shown by the unchanged timing with which antidromically identified cardiac vagal motoneurons (CVM) responded to the arterial pulse. Testing the latency of the HR response to brief electrical stimuli to the right vagus showed that this was also unchanged by clonidine. Nevertheless, vagal stimuli delivered at a fixed time in the cardiac cycle (triggered from the ECG R-wave) slowed HR with a 1-beat delay in the baseline state but a 0-beat delay after clonidine ( n = 5, P < 0.05). This was because clonidine lengthened the diastolic period, allowing the vagal volleys to arrive at the heart just in time to postpone the next beat. Calculations indicate that naturally generated CVM volleys in both humans and rats arrive around this critical time. Clonidine thus reduces τ not by changing central or efferent latencies but simply by slowing the heart.
Green Tea Epigallocatechin Gallate Exhibits Anticancer Effect in Human Pancreatic Carcinoma Cells via the Inhibition of Both Focal Adhesion Kinase and Insulin-Like Growth Factor-I Receptor
Authors: Vu Hoang Anh , Beppu Yuuichi , Chi Hoang Thanh , Sasaki Kousuke , Yamamoto Hideaki , Xinh Phan Thi , Tanii Takashi , Hara Yukihiko , Watanabe Toshiki , Sato Yuko , Ohdomari Iwao
Published: January 2011

The exact molecular mechanism by which epigallocatechin gallate (EGCG) suppresses human pancreatic cancer cell proliferation is unclear. We show here that EGCG-treated pancreatic cancer cells AsPC-1 and BxPC-3 decrease cell adhesion ability on micro-pattern dots, accompanied by dephosphorylations of both focal adhesion kinase (FAK) and insulin-like growth factor-1 receptor (IGF-1R) whereas retained the activations of mitogen-activated protein kinase and mammalian target of rapamycin. The growth of AsPC-1 and BxPC-3 cells can be significantly suppressed by EGCG treatment alone in a dose-dependent manner. At a dose of 100 μM which completely abolishes activations of FAK and IGF-1R, EGCG suppresses more than 50% of cell proliferation without evidence of apoptosis analyzed by PARP cleavage. Finally, the MEK1/2 inhibitor U0126 enhances growth-suppressive effect of EGCG. Our data suggests that blocking FAK and IGF-1R by EGCG could prove valuable for targeted therapy, which can be used in combination with other therapies, for pancreatic cancer.
Lipid Bilayer Composition Affects Transmembrane Protein Orientation and Function
Authors: Hickey Katie D. , Buhr Mary M.
Published: January 2011

Sperm membranes change in structure and composition upon ejaculation to undergo capacitation, a molecular transformation which enables spermatozoa to undergo the acrosome reaction and be capable of fertilization. Changes to the membrane environment including lipid composition, specifically lipid microdomains, may be responsible for enabling capacitation. To study the effect of lipid environment on proteins, liposomes were created using lipids extracted from bull sperm membranes, with or without a protein (Na+K+-ATPase or -amylase). Protein incorporation, function, and orientation were determined. Fluorescence resonance energy transfer (FRET) confirmed protein inclusion in the lipid bilayer, and protein function was confirmed using a colourometric assay of phosphate production from ATP cleavage. In the native lipid liposomes, ATPase was oriented with the subunit facing the outer leaflet, while changing the lipid composition to 50% native lipids and 50% exogenous lipids significantly altered this orientation of Na+K+-ATPase within the membranes.
Fictitious Domain Technique for the Calculation of Time‐Periodic Solutions of Scattering Problem
Authors: Rao Ling , Chen Hongquan
Published: January 2011

The fictitious domain technique is coupled to the improved time‐explicit asymptotic method for calculating time‐periodic solution of wave equation. Conventionally, the practical implementation of fictitious domain method relies on finite difference time discretizations schemes and finite element approximation. Our new method applies finite difference approximations in space instead of conventional finite element approximation. We use the Dirac delta function to transport the variational forms of the wave equations to the differential form and then solve it by finite difference schemes. Our method is relatively easier to code and requires fewer computational operations than conventional finite element method. The numerical experiments show that the new method performs as well as the method using conventional finite element approximation.
Relative Roles of TGF-βand IGFBP-5 in Idiopathic Pulmonary Fibrosis
Authors: Sureshbabu A. , Tonner E. , Allan G. J. , Flint D. J.
Published: January 2011

Although most evident in the skin, the process of scarring, or fibrosis, occurs in all major organs because of impaired epithelial self-renewal. No current therapy exists for Idiopathic pulmonary fibrosis. The major profibrotic factor is TGF-β1 and developing inhibitors is an area of active research. Recently, IGFBP-5 has also been identified as a profibrotic factor, and studies suggest that, while both TGF-β1 and IGFBP-5 activate mesenchymal cells to increase collagen and fibronectin production, their effects on epithelial cells are distinct. TGF-β1 induces cell death and/or EMT in the epithelial cells, exacerbating the disruption of tissue architecture. In contrast, IGFBP-5 induces epithelial cell spreading over collagen or fibronectin matrices, increases secretion of laminin, the epithelial basement membrane, and enhances the survival of epithelial cells in nutrient-poor conditions, as exists in scar tissue. Thus, IGFBP-5 may enhance repair and may be an important target for antifibrotic therapies.
Comparative Study of Human Hematopoietic Cell Engraftment into Balb/c and C57BL/6 Strain of Rag‐2/Jak3 Double‐Deficient Mice
Authors: Ono Ayumi , Hattori Shinichiro , Kariya Ryusho , Iwanaga Sumako , Taura Manabu , Harada Hideki , Suzu Shinya , Okada Seiji
Published: January 2011

Immunodeficient mice are becoming invaluable tools in human stem cell and tumor research. In this study, we generated Rag‐2/Jak3 double‐deficient (Rag‐2−/−Jak3−/−) mice with a C57/BL6 and Balb/c genetic background and compared the human lymphohematopoietic cell engraftment rate. Human cord blood‐derived CD34+ hematopoietic stem cells were successfully engrafted into Balb/c Rag‐2−/−Jak3−/− mice; however, the engraftment rate was far lower in C57/BL6 Rag‐2−/−Jak3−/− mice. Transplantation of human peripheral blood mononuclear cells resulted in the same tendency. Thus, a Balb/c background offers superior engraftment capacity than a C57/BL6 background and provides an attractive model for human hematopoietic cell engraftment.
Experimental Trauma Models: An Update
Authors: Frink Michael , Andruszkow Hagen , Zeckey Christian , Krettek Christian , Hildebrand Frank
Published: January 2011

Treatment of polytrauma patients remains a medical as well as socioeconomic challenge. Although diagnostics and therapy improved during the last decades, multiple injuries are still the major cause of fatalities in patients below 45 years of age. Organ dysfunction and organ failure are major complications in patients with major injuries and contribute to mortality during the clinical course. Profound understanding of the systemic pathophysiological response is crucial for innovative therapeutic approaches. Therefore, experimental studies in various animal models are necessary. This review is aimed at providing detailed information of common trauma models in small as well as in large animals.
EphB3 Is Overexpressed in Non–Small-Cell Lung Cancer and Promotes Tumor Metastasis by Enhancing Cell Survival and Migration
Authors: Ji Xiao-Dan , Li Guo , Feng Yu-Xiong , Zhao Jiang-Sha , Li Jing-Jing , Sun Zhi-Jian , Shi Shuo , Deng Yue-Zhen , Xu Jun-Feng , Zhu Yin-Qiu , Koeffler H. Phillip , Tong Xiang-Jun , Xie Dong
Published: January 2011

Eph receptors, the largest subfamily of transmembrane tyrosine kinase receptors, have been increasingly implicated in various physiologic and pathologic processes, and the roles of the Eph family members during tumorigenesis have recently attracted growing attention. Until now, research on EphB3 function in cancer is limited to focusing on tumor suppression by EphB receptors in colorectal cancer. However, its function in other types of cancer remains poorly investigated. In this study, we explored the function of EphB3 in non–small-cell lung cancer (NSCLC). We found that the expression of EphB3 was significantly upregulated in clinical samples and cell lines, and the expression level correlated with the patient pathologic characteristics, including tumor size, differentiation, and metastasis. Overexpression of EphB3 in NSCLC cell lines accelerated cell growth and migration and promoted tumorigenicity in xenografts in a kinase-independent manner. In contrast, downregulation of EphB3 inhibited cell proliferation and migration and suppressed in vivo tumor growth and metastasis. Furthermore, we showed that silencing of EphB3 inhibited cell growth by reducing DNA synthesis and caspase-8–mediated apoptosis and suppressed cell migration by increasing accumulation of focal adhesion formation. Taken together, our findings suggest that EphB3 provides critical support to the development and progression of NSCLC by stimulating cell growth, migration, and survival, thereby implicating EphB3 as a potential therapeutic target in NSCLC. Cancer Res; 71(3); 1156–66. ©2011 AACR.
ΔNp63α Confers Tumor Cell Resistance to Cisplatin through the AKT1 Transcriptional Regulation
Authors: Sen Tanusree , Sen Nilkantha , Brait Mariana , Begum Shahnaz , Chatterjee Aditi , Hoque Mohammad Obaidul , Ratovitski Edward , Sidransky David
Published: January 2011

Strategies to address resistance to platin drugs are greatly needed in human epithelial cancers (e.g., ovarian, head/neck, and lung) where platins are used widely and resistance occurs commonly. We found that upon ΔNp63α overexpression, AKT1 and phospho-AKT1 levels are upregulated in cancer cells. Investigations using gel-shift, chromatin immunoprecipitation and functional reporter assays implicated ΔNp63α in positive regulation of AKT1 transcription. Importantly, we found that ΔNp63α, AKT1, and phospho-AKT levels are greater in 2008CI3 CDDP-resistant ovarian cancer cells than in 2008 CDDP-sensitive cells. siRNA-mediated knockdown of ΔNp63α expression dramatically decreased AKT1 expression, whereas knockdown of either ΔNp63α or AKT1 decreased cell proliferation and increased death of ovarian and head/neck cancer cells. Conversely, enforced expression of ΔNp63α increased cancer cell proliferation and reduced apoptosis. Together, our findings define a novel ΔNp63α-dependent regulatory mechanism for AKT1 expression and its role in chemotherapeutic resistance of ovarian and head/neck cancer cells. Cancer Res; 71(3); 1167–76. ©2011 AACR.
MicroRNA-1258 Suppresses Breast Cancer Brain Metastasis by Targeting Heparanase
Authors: Zhang Lixin , Sullivan Peggy S. , Goodman Jerry C. , Gunaratne Preethi H. , Marchetti Dario
Published: January 2011

Heparanase (HPSE) is a potent protumorigenic, proangiogenic, and prometastatic enzyme that is overexpressed in brain metastatic breast cancer (BMBC). However, little is known about the regulation of this potential therapeutic target in BMBC, which remains very poorly managed in the clinic. We hypothesized that HPSE gene expression might be regulated by micro RNA that might be exploited therapeutically. Using miRanda and RNAhybrid, we identified miR-1258 as a candidate micro RNA that may directly target HPSE and suppress BMBC. In support of our hypothesis, we found that miR-1258 levels inversely correlated with heparanase expression, enzymatic activity, and cancer cell metastatic propensities, being lowest in highly aggressive BMBC cell variants compared with either nontumorigenic or nonmetastatic human mammary epithelial cells. These findings were validated by analyses of miR-1258 and heparanase content in paired clinical specimens of normal mammary gland versus invasive ductal carcinoma, and primary breast cancer versus BMBC. In regulatory experiments, miR-1258 inhibited the expression and activity of heparanase in BMBC cells, whereas modulating heparanase blocked the phenotypic effects of miR-1258. In functional experiments, stable expression of miR-1258 in BMBC cells inhibited heparanase in vitro cell invasion and experimental brain metastasis. Together, our findings illustrate how micro RNA mechanisms are linked to brain metastatic breast cancer through heparanase control, and they offer a strong rationale to develop heparanase-based therapeutics for treatment of cancer patients with brain metastases, BMBC in particular. Cancer Res; 71(3); 645–54. ©2011 AACR.
Three-Dimensional Culture of Mouse Renal Carcinoma Cells in Agarose Macrobeads Selects for a Subpopulation of Cells with Cancer Stem Cell or Cancer Progenitor Properties
Authors: Smith Barry H. , Gazda Lawrence S. , Conn Bryan L. , Jain Kanti , Asina Shirin , Levine Daniel M. , Parker Thomas S. , Laramore Melissa A. , Martis Prithy C. , Vinerean Horatiu V. , David Eric M. , Qiu Suizhen , Cordon-Cardo Carlos , Hall Richard D. , Gordon Bruce R. , Diehl Carolyn H. , Stenzel Kurt H. , Rubin Albert L.
Published: January 2011

The culture of tumor cell lines in three-dimensional scaffolds is considered to more closely replicate the in vivo tumor microenvironment than the standard method of two-dimensional cell culture. We hypothesized that our method of encapsulating and maintaining viable and functional pancreatic islets in agarose–agarose macrobeads (diameter 6–8 mm) might provide a novel method for the culture of tumor cell lines. In this report we describe and characterize tumor colonies that form within macrobeads seeded with mouse renal adenocarcinoma cells. Approximately 1% of seeded tumor cells survive in the macrobead and over several months form discrete elliptical colonies appearing as tumor cell niches with increasing metabolic activity in parallel to colony size. The tumor colonies demonstrate ongoing cell turnover as shown by BrdU incorporation and activated caspase-3 and TUNEL staining. Genes upregulated in the tumor colonies of the macrobead are likely adaptations to this novel environment, as well as an amplification of G1/S cell-cycle checkpoints. The data presented, including SCA-1 and Oct4 positivity and the upregulation of stem cell–like genes such as those associated with the Wnt pathway, support the notion that the macrobead selects for a subpopulation of cells with cancer stem cell or cancer progenitor properties. Cancer Res; 71(3); 716–24. ©2011 AACR.
Spatial Regulation of RhoA Activity during Pancreatic Cancer Cell Invasion Driven by Mutant p53
Authors: Timpson Paul , McGhee Ewan J. , Morton Jennifer P. , von Kriegsheim Alex , Schwarz Juliane P. , Karim Saadia A. , Doyle Brendan , Quinn Jean A. , Carragher Neil O. , Edward Mike , Olson Michael F. , Frame Margaret C. , Brunton Valerie G. , Sansom Owen J. , Anderson Kurt I.
Published: January 2011

The ability to observe changes in molecular behavior during cancer cell invasion in vivo remains a major challenge to our understanding of the metastatic process. Here, we demonstrate for the first time, an analysis of RhoA activity at a subcellular level using FLIM-FRET (fluorescence lifetime imaging microscopy-fluorescence resonance energy transfer) imaging in a live animal model of pancreatic cancer. In invasive mouse pancreatic ductal adenocarcinoma (PDAC) cells driven by mutant p53 (p53R172H), we observed a discrete fraction of high RhoA activity at both the leading edge and rear of cells in vivo which was absent in two-dimensional in vitro cultures. Notably, this pool of active RhoA was absent in noninvasive p53fl knockout PDAC cells, correlating with their poor invasive potential in vivo. We used dasatanib, a clinically approved anti-invasive agent that is active in this model, to illustrate the functional importance of spatially regulated RhoA. Dasatanib inhibited the activity of RhoA at the poles of p53R172H cells in vivo and this effect was independent of basal RhoA activity within the cell body. Taken together, quantitative in vivo fluorescence lifetime imaging illustrated that RhoA is not only necessary for invasion, but also that subcellular spatial regulation of RhoA activity, as opposed to its global activity, is likely to govern invasion efficiency in vivo. Our findings reveal the utility of FLIM-FRET in analyzing dynamic biomarkers during drug treatment in living animals, and they also show how discrete intracellular molecular pools might be differentially manipulated by future anti-invasive therapies. Cancer Res; 71(3); 747–57. ©2011 AACR.
PTEN Level in Tumor Suppression: How Much Is Too Little?
Authors: Carracedo Arkaitz , Alimonti Andrea , Pandolfi Pier Paolo
Published: January 2011

The importance of PTEN (phosphatase and tensin homolog located on chromosome 10) in cancer has surpassed all predictions and expectations from the time it was discovered and has qualified this gene as one of the most commonly mutated and deleted tumor suppressors in human cancer. PTEN levels are frequently found downregulated in cancer, even in the absence of genetic loss or mutation. PTEN is heavily regulated by transcription factors, microRNAs, competitive endogenous RNAs (such as the PTEN pseudogene), and methylation, whereas the tumor suppressive activity of the PTEN protein can be altered at multiple levels through aberrant phosphorylation, ubiquitination, and acetylation. These regulatory cues are presumed to play a key role in tumorigenesis through the alteration of the appropriate levels, localization, and activity of PTEN. The identification of all these levels of PTEN regulation raises, in turn, a key corollary question: How low should PTEN level(s) or activity drop in order to confer cancer susceptibility at the organismal level? Our laboratory and others have approached this question through the genetic manipulation of Pten in the mouse. This work has highlighted the exquisite and tissue-specific sensitivity to subtle reductions in Pten levels toward tumor initiation and progression with important implications for cancer prevention and therapy. Cancer Res; 71(3); 629–33. ©2011 AACR.
Intracellular CD24 Inhibits Cell Invasion by Posttranscriptional Regulation of BART through Interaction with G3BP
Authors: Taniuchi Keisuke , Nishimori Isao , Hollingsworth Michael A.
Published: January 2011

We report a novel function for the CD24 molecule in pancreatic cancer cells. Intracellular CD24 is associated with stress granules that contain specific mRNAs and RNA-binding proteins that regulate mRNA stability and translation. Intracellular CD24 in stress granules is associated with G3BP, a phosphorylation-dependent endoribonuclease. The vesicles in which the CD24/G3BP complex localizes are transported toward cell protrusions in migrating cells. We show that G3BP binds to and degrades Binder of Arl Two (BART) mRNA. BART was originally identified as a binding partner of ARL2, a small G-protein implicated as a regulator of microtubule dynamics and folding. Intracellular CD24 inhibits the specific endoribonuclease activity of G3BP toward BART mRNA in stress granules. We show that knockdown of CD24 increases retroperitoneal invasion and liver metastasis of pancreatic cancer cells in an orthotopic xenograft model, and that BART also prevents retroperitoneal invasion and liver metastasis of pancreatic cancer cells. Our results imply that surface CD24 may play a role in the inhibition of cell invasion and metastasis, and that intracellular CD24 inhibits invasiveness and metastasis through its influence on the posttranscriptional regulation of BART mRNA levels via G3BP RNase activity. Cancer Res; 71(3); 895–905. ©2011 AACR.
In VivoProfiling of Hypoxic Gene Expression in Gliomas Using the Hypoxia Marker EF5 and Laser-capture Microdissection
Authors: Marotta Diane , Karar Jayashree , Jenkins W. Timothy , Kumanova Monika , Jenkins Kevin W. , Tobias John W. , Baldwin Donald , Hatzigeorgiou Artemis , Alexiou Panagiotis , Evans Sydney M. , Alarcon Rodolfo , Maity Amit , Koch Cameron , Koumenis Constantinos
Published: January 2011

Hypoxia is a key determinant of tumor aggressiveness, yet little is known regarding hypoxic global gene regulation in vivo. We used the hypoxia marker EF5 coupled with laser-capture microdissection to isolate RNA from viable hypoxic and normoxic regions of 9L experimental gliomas. Through microarray analysis, we identified several mRNAs (including the HIF targets Vegf, Glut-1, and Hsp27) with increased levels under hypoxia compared with normoxia both in vitro and in vivo. However, we also found striking differences between the global in vitro and in vivo hypoxic mRNA profiles. Intriguingly, the mRNA levels of a substantial number of immunomodulatory and DNA repair proteins including CXCL9, CD3D, and RAD51 were found to be downregulated in hypoxic areas in vivo, consistent with a protumorigenic role of hypoxia in solid tumors. Immunohistochemical staining verified increased HSP27 and decreased RAD51 protein levels in hypoxic versus normoxic tumor regions. Moreover, CD8+ T cells, which are recruited to tumors upon stimulation by CXCL9 and CXCL10, were largely excluded from viable hypoxic areas in vivo. This is the first study to analyze the influence of hypoxia on mRNA levels in vivo and can be readily adapted to obtain a comprehensive picture of hypoxic regulation of gene expression and its influence on biological functions in solid tumors. Cancer Res; 71(3); 779–89. ©2011 AACR.
A Unique Spectrum of Somatic PIK3CA (p110α) Mutations Within Primary Endometrial Carcinomas
Authors: Rudd Meghan L. , Price Jessica C. , Fogoros Sarah , Godwin Andrew K. , Sgroi Dennis C. , Merino Maria J. , Bell Daphne W.
Published: January 2011

Purpose: The goal of this study was to comprehensively define the incidence of mutations in all exons of PIK3CA in both endometrioid endometrial cancer (EEC) and nonendometrioid endometrial cancer (NEEC).

Experimental Design: We resequenced all coding exons of PIK3CA and PTEN, and exons 1 and 2 of KRAS, from 108 primary endometrial tumors. Somatic mutations were confirmed by sequencing matched normal DNAs. The biochemical properties of a subset of novel PIK3CA mutations were determined by exogenously expressing wild type and mutant constructs in U2OS cells and measuring levels of AKTSer473 phosphorylation.

Results: Somatic PIK3CA mutations were detected in 52.4% of 42 EECs and 33.3% of 66 NEECs. Half (29 of 58) of all nonsynonymous PIK3CA mutations were in exons 1–7 and half were in exons 9 and 20. The exons 1–7 mutations localized to the ABD, ABD-RBD linker and C2 domains of p110α. Within these regions, Arg88, Arg93, Gly106, Lys111, Glu365, and Glu453, were recurrently mutated; Arg88, Arg93, and Lys111 formed mutation hotspots. The p110α-R93W, -G106R, -G106V, -K111E, -delP449-L455, and -E453K mutants led to increased levels of phospho-AKTSer473 compared to wild-type p110α. Overall, 62% of exons 1–7 PIK3CA mutants and 64% of exons 9–20 PIK3CA mutants were activating; 72% of exon 1–7 mutations have not previously been reported in endometrial cancer.

Conclusions: Our study identified a new subgroup of endometrial cancer patients with activating mutations in the amino-terminal domains of p110α; these patients might be appropriate for consideration in clinical trials of targeted therapies directed against the PI3K pathway. Clin Cancer Res; 17(6); 1331–40. ©2011 AACR.
Phase I Study of Decitabine in Combination with Vorinostat in Patients with Advanced Solid Tumors and Non-Hodgkin's Lymphomas
Authors: Stathis Anastasios , Hotte Sebastien J. , Chen Eric X. , Hirte Holger W. , Oza Amit M. , Moretto Patricia , Webster Sheila , Laughlin Anne , Stayner Lee-Anne , McGill Shauna , Wang Lisa , Zhang Wen-jiang , Espinoza-Delgado Igor , Holleran Julianne L. , Egorin Merrill J. , Siu Lillian L.
Published: January 2011

Purpose: This phase I study evaluated the safety, tolerability, pharmacokinetics, and preliminary efficacy of the combination of decitabine with vorinostat.

Patients and Methods: Patients with advanced solid tumors or non-Hodgkin's lymphomas were eligible. Sequential and concurrent schedules were studied.

Results: Forty-three patients were studied in 9 different dose levels (6 sequential and 3 concurrent). The maximum tolerated dose (MTD) on the sequential schedule was decitabine 10 mg/m2/day on days 1 to 5 and vorinostat 200 mg three times a day on days 6 to 12. The MTD on the concurrent schedule was decitabine 10 mg/m2/day on days 1 to 5 with vorinostat 200 mg twice a day on days 3 to 9. However, the sequential schedule of decitabine 10 mg/m2/day on days 1 to 5 and vorinostat 200 mg twice a day on days 6 to 12 was more deliverable than both MTDs with fewer delays on repeated dosing and it represents the recommended phase II (RP2D) dose of this combination. Dose-limiting toxicities during the first cycle consisted of myelosuppression, constitutional and gastrointestinal symptoms and occurred in 12 of 42 (29%) patients evaluable for toxicity. The most common grade 3 or higher adverse events were neutropenia (49% of patients), thrombocytopenia (16%), fatigue (16%), lymphopenia (14%), and febrile neutropenia (7%). Disease stabilization for 4 cycles or more was observed in 11 of 38 (29%) evaluable patients.

Conclusion: The combination of decitabine with vorinostat is tolerable on both concurrent and sequential schedules in previously treated patients with advanced solid tumors or non-Hodgkin's lymphomas. The sequential schedule was easier to deliver. The combination showed activity with prolonged disease stabilization in different tumor types. Clin Cancer Res; 17(6); 1582–90. ©2011 AACR.
ERCC1 and ERCC2 Polymorphisms Predict Clinical Outcomes of Oxaliplatin-Based Chemotherapies in Gastric and Colorectal Cancer: A Systemic Review and Meta-analysis
Authors: Yin Ming , Yan Jingrong , Martinez-Balibrea Eva , Graziano Francesco , Lenz Heinz-Josef , Kim Hyo-Jin , Robert Jacques , Im Seock-Ah , Wang Wei-Shu , Etienne-Grimaldi Marie-Christine , Wei Qingyi
Published: January 2011

Purpose: Nucleotide excision repair (NER) modulates platinum-based chemotherapeutic efficacy by removing drug-produced DNA damage. To summarize published data on the association between polymorphisms of NER genes (ERCC1 and ERCC2) and responses to oxaliplatin-based chemotherapies, we carried out a meta-analysis of gastric and colorectal cancer for commonly studied polymorphisms ERCC1 rs11615C>T and ERCC2 rs13181T>G.

Patients and Methods: In 17 previously published studies, 1,787 cancer patients were treated with the oxaliplatin-based regimen. Primary outcomes included therapeutic response (TR; i.e., complete response + partial response vs. stable disease + progressive disease), progression-free survival (PFS), and overall survival (OS). We calculated OR or HR with 95% CIs to estimate the risk or hazard.

Results: We found consistent and clinically substantial risk or hazard for TR, PFS, and OS in the oxaliplatin-treated gastric and colorectal cancer patients with an ethnic discrepancy. For ERCC1 rs11615C>T, the T allele was associated with reduced response and poor PFS and OS in Asians (TR: OR = 0.53 and 95% CI = 0.35–0.81; PFS: HR = 1.69 and 95% CI = 1.05–2.70; and OS: HR = 2.03 and 95% CI = 1.60–2.59). For ERCC2 rs13181T>G, the G allele was associated with reduced response and poor PFS and OS in Caucasians (TR: OR = 0.56 and 95% CI = 0.35–0.88; PFS: HR = 1.41 and 95% CI = 1.02–1.95; and OS: HR = 1.42 and 95% CI = 1.11–1.81).

Conclusions: NER ERCC1 rs11615C>T and ERCC2 rs13181T>G polymorphisms are useful prognostic factors in oxaliplatin-based treatment of gastric and colorectal cancer. Larger studies and further clinical trials are warranted to confirm these findings. Clin Cancer Res; 17(6); 1632–40. ©2011 AACR.
Response to Combined Molecular Targeting: Defining the Role of P-STAT3
Authors: Egloff Ann Marie , Grandis Jennifer R.
Published: January 2011

Src family kinase (SFK)–targeting agents are currently undergoing clinical investigation for treatment of solid malignancies. Epidermal growth factor receptor (EGFR)–independent phosphorylation of STAT3 (P-STAT3) has been identified as a mechanism of tumor resistance to agents targeting SFK. Tumor P-STAT3 levels may be an important indicator of EGFR- and SKF-targeted antitumor treatment efficacy. Clin Cancer Res; 17(3); 393–5. ©2011 AACR.
Heme Oxygenase-1 Does Not Mediate the Effects of Extracellular Acidosis on Vascular Smooth Muscle Cell Proliferation, Migration, and Susceptibility to Apoptosis
Authors: Brenninkmeijer Lineke , Kuehl Constantin , Miele Geldart Adriana , Arons Elena , Christou Helen
Published: January 2011

Background: Unbalanced vascular smooth muscle cell (VSMC) proliferation, migration, and apoptosis contribute to vascular disorders such as atherosclerosis, restenosis, and pulmonary hypertension. The effect of extracellular acidosis (EA) on VSMC homeostasis is incompletely understood but we previously reported that EA increases heme oxygenase-1 (HO-1) expression in VSMCs. Since HO-1 regulates VSMC proliferation and apoptosis we sought to define the role of HO-1 in VSMC responses to EA. Methods: Mouse aortic smooth muscle cells (MASMCs) were isolated from wild-type and HO-1-null mice. Cell proliferation and migration assays were done in a physiologic pH (7.4) or EA (pH 6.8). VSMC apoptosis in response to hydrogen peroxide was assessed by JC-1 staining, caspase-3 cleavage, annexin V, and Hoechst staining. Results: Wild-type MASMCs showed decreased proliferation and migration at pH 6.8 compared to pH 7.4. This observation was also true in HO-1-null MASMCs. Although wild-type and HO-1-null cells showed differences in the mode and kinetics of cell death, both genotypes exhibited increased susceptibility to hydrogen peroxide-induced apoptosis at pH 6.8 compared to 7.4. Conclusions: EA inhibits VSMC proliferation and migration and increases susceptibility to oxidant-induced apoptosis. These effects of acidosis on VSMC homeostasis are independent of HO-1.
Systolic Right Ventricular Function in Preterm and Term Neonates: Reference Values of the Tricuspid Annular Plane Systolic Excursion (TAPSE) in 258 Patients and Calculation of Z-Score Values
Authors: Koestenberger Martin , Nagel Bert , Ravekes William , Urlesberger Berndt , Raith Wolfgang , Avian Alexander , Halb Verena , Cvirn Gerhard , Fritsch Peter , Gamillscheg Andreas
Published: January 2011

Background: The tricuspid annular plane systolic excursion (TAPSE) is an echocardiographic measurement to assess right ventricular systolic function in adults and children. Objective: We determined growth- and birth weight-related changes of TAPSE to establish reference values in preterm and term neonates. Methods: A prospective study was conducted in a group of 258 preterm and term neonates (age: 25+0 to 40+6 weeks of gestation, birth weight: 530–4,200 g). Results: The TAPSE ranged from a mean of 0.44 cm (Z-score ±2: 0.30–0.59 cm) in preterm neonates in the 26th week of gestation to 1.03 cm (Z-score ±2: 0.85–1.21 cm) in term neonates in the 41st week of gestation. The TAPSE values increased in a linear way from the 26th to 41st week of gestation. TAPSE, week of gestation and weight are strongly correlated: Pearson’s correlation coefficient was 0.93 for week of gestation – TAPSE (p < 0.001), 0.93 for week of gestation – birth weight (p < 0.001), and 0.89 for birth weight – TAPSE (p < 0.001). There was no statistically significant difference of normal TAPSE values between female and male patients (p = 0.987). Conclusion: Z-scores of TAPSE values were calculated and percentile charts were established to serve as reference data for ready application in preterm and term neonates with structurally normal hearts and with congenital heart disease in the future.
Cloning of a Gene Encoding β-Glucosidase from Chaetomium thermophilum CT2 and Its Expression in Pichia pastoris
Authors: Xu Rongyan , Teng Fangchao , Zhang Chao , Li Duochuan
Published: January 2011

A new thermostable β-glucosidase gene (bgl) from Chaetomium thermophilum CT2 was cloned, sequenced and expressed. The full-length DNA of bgl was 3,101 bp and included three introns. The full-length cDNA contained an open reading frame of 2,604-bp nucleotides, encoding 867 amino acids with a potential secretion signal. The C. thermophilum CT2 β-glucosidase gene was functionally expressed in Pichia pastoris. The purified recombinant β-glucosidase was a 119-kDa glycoprotein with an optimum catalytic activity at pH 5.0 and 60°C. The enzyme was stable at 50°C, and retained 67.7% activity after being kept at 60°C for 1 h; the half-time of the enzyme at 65°C was approximately 55 min, and even retained 29.7% activity after incubation at 70°C for 10 min.
Sustained Inflations: Comparing Three Neonatal Resuscitation Devices
Authors: Klingenberg Claus , Dawson Jennifer A. , Gerber Angela , Kamlin C. Omar F. , Davis Peter G. , Morley Colin J.
Published: January 2011

Background: Some national resuscitation guidelines advocate using sustained initial inflations (2–3 s) for babies requiring resuscitation. Inflation times ≧10 s have been used for preterm infants. Objectives: This study examines the ability of operators of varying experience to provide a sustained inflation using three different manual ventilation devices. Methods: We compared a self-inflating bag, a flow-inflating bag and a pressure-limited T-piece device. Fifty clinical staff members from five professional groups gave a sustained inflation with a target peak pressure of 30 cm H2O and target duration of 10 s to an internal leak-free manikin. We measured peak inflating pressure (PIP) and mean inflating pressure (MIP) during the sustained inflation, and the duration of inflating pressure (IP) >20 and 25 cm H2O. Results: Median (IQR) duration of IP >25 cm H2O was: self-inflating bag 2.5 s (0.8–5.7), flow-inflating bag 10.6 s (8.4–12.9) and the T-piece 10.7 s (8.9–11.9). There was a weak correlation between experience using a self-inflating bag and longer inflation times (R = 0.290, p = 0.041). When compared with the T-piece, the flow-inflating bag had lower mean MIP (27.0 ± 1.8 vs. 28.8 ± 2.0 cm H2O) and higher mean PIP (32.3 ± 3.7 vs. 29.8 ± 1.8 cm H2O). There were no differences in performance between operator groups. Conclusion: The T-piece provided consistent PIP during a single 10 s sustained inflation with less variation in pressure compared with the flow-inflating bag. Sustained inflations >3 s were difficult to achieve with a self-inflating bag.
Influence of Age on the Relationship between Alcohol Consumption and Metabolic Syndrome
Authors: Wakabayashi Ichiro
Published: January 2011

Background: Relationships between alcohol consumption and risks for metabolic syndrome in general populations are very controversial. It is unknown whether age influences the relationship between alcohol intake and the prevalence of metabolic syndrome. Objective: The purpose of this study was to determine whether age influences the relationship between alcohol consumption and metabolic syndrome. Methods: Men aged ≧35 and <45 years (younger group) and those aged ≧65 years (older group), matched for alcohol intake and smoking history, were divided into four subgroups by alcohol intake [non-, light (<22 g ethanol/day), heavy (≧22 and <44 g ethanol/day) and very heavy (≧44 g ethanol/day) drinkers]. Odds ratios (ORs) versus nondrinkers for each risk factor and metabolic syndrome were compared between the younger and older groups. Results: Both in the younger and older groups, ORs for high blood pressure and low HDL cholesterol were significantly high and low, respectively, in all drinker groups. In younger subjects, the OR for large waist circumference was significantly low in light drinkers, and the OR for high hemoglobin A1c was significantly low in light and heavy drinkers, while these associations were not found in older subjects. The OR for metabolic syndrome was significantly low in light and heavy drinkers in the younger subjects but was not significant in any drinker groups in older subjects. Conclusion: Age influences the relationships between alcohol consumption and atherosclerotic risk factors, and there is a significant association between alcohol intake and a lower risk for metabolic syndrome in young men but not in elderly men.
Innovative Sunscreen Formulation Based on Benzophenone-3-Loaded Chitosan-Coated Polymeric Nanocapsules
Authors: Siqueira N.M. , Contri R.V. , Paese K. , Beck R.C.R. , Pohlmann A.R. , Guterres S.S.
Published: January 2011

Aim: To evaluate the effect of cationic coating of polymeric nanocapsules in sunscreen formulations on the in vitro skin penetration of benzophenone-3. Methods: Benzophenone-3-loaded nanocapsules were prepared by the interfacial deposition of poly(Ε-caprolactone) and coated by using a chitosan solution. The nanoparticles were characterized and incorporated in hydrogels. The presence of nanoparticles in hydroxyethyl cellulose gels was observed by transmission electron microscopy and photon correlation spectroscopy. Penetration studies were carried out using Franz cells with porcine skin membranes. Results: Benzophenone-3-loaded chitosan-coated nanocapsules presented a mean size of 202 ± 7 nm and positive zeta potential (+21 ± 1 mV), while these values for the uncoated nanocapsules were 175 ± 1 nm and –8 ± 1 mV. Penetration profiles showed that a higher amount of benzophenone-3 remained at the skin surface and a lower amount was found in the receptor compartment after the application of the formulation containing chitosan-coated nanocapsules compared to a formulation containing its free form. Conclusions: Hydrogel containing benzophenone-3 chitosan-coated nanocapsules represents an innovative formulation to overcome limitations of sunscreen daily use.
Seasonal Variation in Hospital Admission in Patients with Heart Failure and Its Effect on Prognosis
Authors: Gotsman Israel , Zwas Donna , Admon Dan , Lotan Chaim , Keren Andre
Published: January 2011

Background: A seasonal variation in hospital admissions in patients with heart failure (HF) has been described and most admissions occur during the winter season. The effect of this seasonal variation on prognosis is less clear. Objectives: To evaluate the effect of the seasonal timing of hospital admission on clinical outcome in patients with HF. Methods: We prospectively enrolled 362 consecutive patients hospitalized with a definite clinical diagnosis of HF during a 2-year period. Patients were followed clinically for a period of 1 year. Results: There was a prominent seasonal variation in hospital admissions in patients with HF with peak admissions during the winter. The admission rate inversely correlated with the average monthly temperature. Admission during the summer season was a significant predictor of reduced survival (59 vs. 75%, p < 0.01). Cox regression analysis demonstrated that independent predictors of reduced survival after adjustment for other predictors were admission during the hottest 6 months or admission during the summer. In addition, increased mean environmental admission temperature was an independent predictor of reduced survival. Conclusions: Seasonal temperature has a significant effect on the rate of hospital admission in patients with HF. Admission during warmer weather is a sign of a poor prognosis.