bluuebunny/crossref_metadata_2025 huggingface dataset:
Short-term high-intensity interval training improves phosphocreatine recovery kinetics following moderate-intensity exercise in humans
Authors: Forbes Sean C. , Slade Jill M. , Meyer Ronald A.
Published: December 2008

Previous studies have shown that high-intensity training improves biochemical markers of oxidative potential in skeletal muscle within a 2-week period. The purpose of this study was to examine the effect of short-term high-intensity interval training on the time constant (τ) of phosphocreatine (PCr) recovery following moderate-intensity exercise, an in vivo measure of functional oxidative capacity. Seven healthy active subjects (age, 21 ± 4 years; body mass, 69 ± 11 kg) performed 6 sessions of 4–6 maximal-effort 30 s cycling intervals within a 2-week period, and 7 subjects (age, 24 ± 5 years; body mass, 80 ± 15 kg) served as controls. Prior to and following training, phosphorous-31 magnetic resonance spectroscopy (31P-MRS; GE 3T Excite System) was used to measure relative changes in high-energy phosphates and intracellular pH of the quadriceps muscles during gated dynamic leg-extension exercise (3 cycles of 90 s exercise and 5 min of rest). A monoexponential model was used to estimate the τ of PCr recovery. The τ of PCr recovery after leg-extension exercise was reduced by 14% with high-intensity interval training (pretraining, 43 ± 14 s vs. post-training, 37 ± 15 s; p < 0.05) with no change in the control group (44 ± 12 s vs. 43 ± 12 s, respectively; p > 0.05). These findings demonstrate that short-term high-intensity interval training is an effective means of increasing functional oxidative capacity in skeletal muscle.
Diabetaction – Programme d’exercices pour personnes diabétiques de type 2 ou à risque : effets sur la pratique d’activités physiques, la condition physique, la qualité de vie et différents paramètres de santé
Authors: Mathieu Marie-Eve
Published: December 2008

S’inscrivant dans le cadre de la Stratégie canadienne sur le diabète de Santé Canada, le projet Diabetaction vise à réduire les risques liés à la sédentarité chez les personnes diabétiques de type 2 ou à risque de développer la maladie. Ce programme d’initiation à l’activité physique a été développé à partir des lignes directrices d’organismes reconnus, des connaissances et résultats de la littérature scientifique, des résultats obtenus lors de groupes de discussion effectués avec la population cible et de l’expertise de l’équipe multidisciplinaire impliquée. Le premier article de la thèse vise à expliquer en quoi consiste le programme Diabetaction et comment il est en lien avec les résultats des groupes de discussion et les recommandations en activité physique pour les personnes diabétiques. Les résultats obtenus lors de l’évaluation du programme en milieu universitaire et de son implantation dans des milieux cliniques de la communauté font pour leur part l’objet des articles 2, 3 et 4. Notons tout d’abord que l’étude préliminaire réalisée en milieu universitaire a démontré que les sujets ayant pris part à au moins 50 % des séances de groupe ont amélioré plusieurs paramètres : niveau d’activités physiques, puissance aérobie, force de préhension, masse corporelle, circonférence de taille, épaisseur des plis cutanés, lipoprotéines de haute densité, fréquence cardiaque et pression artérielle systolique au repos (deuxième article). Certains de ces changements ont contribué à la diminution de la prévalence du syndrome métabolique post-intervention. Dans le troisième article, nous avons rapporté que plusieurs paramètres de la qualité de vie furent aussi significativement améliorés après le programme Diabetaction et que ces changements étaient principalement associés aux modifications de la puissance aérobie, de la force de préhension, de la masse corporelle et des plis cutanés. Finalement, dans le quatrième article, les participants ayant pris part au programme dans les milieux cliniques étaient plus actifs après l’intervention tout en ayant amélioré certains paramètres de la condition physique, du contrôle hémodynamique et de la qualité de vie. Cependant, la plupart de ces changements ont aussi été documentés dans le groupe témoin. Ces résultats soulèvent des questions quant à l’effet du programme et ce, bien que les participants à ce dernier aient rapporté une grande appréciation face à celui-ci, qu’ils aient perçu des améliorations de plusieurs facteurs qu’ils jugeaient importants et qu’ils aient maintenu plusieurs acquis jusqu’à 6 mois après l’intervention.
Greater bilateral deficit in leg press than in handgrip exercise might be linked to differences in postural stability requirements
Authors: Magnus Charlene R.A. , Farthing Jonathan P.
Published: December 2008

Bilateral deficit is defined as the difference in the summed force between contracting muscles alone and contracting contralateral homologous muscles in combination. The purpose of the study was to investigate how postural stability influences bilateral deficit by comparing an exercise requiring more postural stability (the leg press) with an exercise requiring less postural stability (the handgrip). Eight participants volunteered for the study (3 males, 5 females). Maximal strength was determined by a 1-repetition maximum for the leg press (weight machine) and handgrip (dynamometer) exercises. Electromyography was used to measure activation of the effectors (flexor carpi ulnaris for the handgrip and vastus lateralis for the leg press) and the core muscles (rectus abdominis and external obliques). Bilateral deficit was greater in the leg press (–12.08 ± 10.22%) than the handgrip (–0.677 ± 5.00%; p < 0.05). Muscle activation of the effectors and core muscles was not significantly different between unilateral and bilateral conditions for either exercise. However, core muscle activation was significantly greater during the leg press (48.30 ± 19.60 µV) than during the handgrip (16.50 ± 8.10 µV; p < 0.05) exercise. These results support the hypothesis that an exercise requiring more postural stability (e.g., the leg press) will have a larger deficit and greater activation of core muscles than an exercise requiring less postural stability (e.g., the handgrip). Since the bilateral deficit was only apparent for the leg press exercise, we conclude that postural stability requirements might influence the magnitude of bilateral deficit.
Following 2 diet-restricted male outdoor rock climbers: impact on oxidative stress and improvements in markers of cardiovascular risk
Authors: Merrells Krystal J. , Friel James K. , Knaus Maria , Suh Miyoung
Published: December 2008

Lower body fat percentage is positively associated with climbing performance. This may lead climbers to practice unhealthy diet restriction when no sport-specific nutrition information exists. This study examined whether prolonged diet restriction affects body composition, oxidative stress, or other potential health risks in outdoor rock climbers. Two healthy male climbers conducted a 5 week rock climbing trip with a limited food budget ($1 each per day). Subjects underwent an energy restriction of approximately 40%. Loss of body weight and fat mass at week 5 were 5.8% and 16.1%, respectively, and were accompanied by significant subcutaneous fat loss in the iliac crest and abdomen. Triacylglycerols (TG), free fatty acids and C-reactive protein (CRP) dramatically decreased from baseline to week 2, and then maintained the lower level until week 5. Plasma vitamin C was below the normal range, and F2-isoprostanes, a marker of oxidative stress, continuously increased to week 5. Superoxide dismutase and glutathione peroxidase increased to week 2, but had returned to baseline levels at week 5. These results indicate that prolonged reduced energy intake while climbing may have an impact on weight loss and fat mass loss, which may contribute to low circulating TG and CRP, indicating improvements in markers of cardiovascular risk, and may lead to increased oxidative stress and reduced circulating antioxidants. Further studies are warranted to determine whether antioxidant supplementation or increased energy intake reduce oxidative stress.
Caffeine and sports performance
Authors: Burke Louise M.
Published: December 2008

Athletes are among the groups of people who are interested in the effects of caffeine on endurance and exercise capacity. Although many studies have investigated the effect of caffeine ingestion on exercise, not all are suited to draw conclusions regarding caffeine and sports performance. Characteristics of studies that can better explore the issues of athletes include the use of well-trained subjects, conditions that reflect actual practices in sport, and exercise protocols that simulate real-life events. There is a scarcity of field-based studies and investigations involving elite performers. Researchers are encouraged to use statistical analyses that consider the magnitude of changes, and to establish whether these are meaningful to the outcome of sport. The available literature that follows such guidelines suggests that performance benefits can be seen with moderate amounts (~3 mg·kg–1 body mass) of caffeine. Furthermore, these benefits are likely to occur across a range of sports, including endurance events, stop-and-go events (e.g., team and racquet sports), and sports involving sustained high-intensity activity lasting from 1–60 min (e.g., swimming, rowing, and middle and distance running races). The direct effects on single events involving strength and power, such as lifts, throws, and sprints, are unclear. Further studies are needed to better elucidate the range of protocols (timing and amount of doses) that produce benefits and the range of sports to which these may apply. Individual responses, the politics of sport, and the effects of caffeine on other goals, such as sleep, hydration, and refuelling, also need to be considered.
Crack spacing for offshore structures
Authors: Hossin M. , Marzouk H.
Published: December 2008

The main focus of this investigation is directed toward the examination of crack-spacing expressions suitable for offshore concrete structure applications. Offshore structures are unique structures that are constantly exposed to harsh environmental conditions, including exposure to seawater and sea spray. The splash zone of an offshore structure is the section of the platform that is the most exposed to both a harsh marine environment and seawater. The design of offshore structures is controlled by mandatory design codes to ensure structural safety and integrity. Most of the available expressions for crack spacing were developed for building structures using normal-strength concrete and normal concrete cover. However, offshore structures are built using high-strength concrete with a thick concrete cover. Very little information is published on the crack analysis of high-strength concrete with a thick concrete cover for offshore applications. An experimental testing program was designed to examine the effects of concrete cover and the bar spacing of normal- and high-strength concrete on crack spacing. The different code expressions are evaluated with respect to the experimental results.
Smoothness variations in early-age jointed plain concrete pavements
Authors: Kim Sunghwan , Ceylan Halil , Gopalakrishnan Kasthurirangan
Published: December 2008

This paper discusses the variations in the early-age pavement smoothness at different measurement times and locations in three jointed plain concrete pavements (JPCPs) representing different ranges of construction times. Surface profile measurements were made during the early morning and late afternoon hours at different locations of the instrumented JPCPs during the first 7 d after construction. Variations in pavement temperature during this critical period were monitored using temperature sensors installed within the test sections. The results show that measurable changes of early-age jointed plain concrete pavement (JPCP) smoothness do occur at different measurement times and locations. Within the scope of this study, it can be concluded that the variations in early-age JPCP smoothness can be significant from the standpoint of smoothness specifications. The findings of this study also indicate that morning paving produces consistent smoothness measurements when compared with afternoon paving.
Temperature–density relationship of hot-mix asphalt pavement after completed rolling
Authors: Hanna Awad S. , Lee Min-Jae , Schoenfelder Stephen M. , Lee Chanyoung
Published: December 2008

This study investigates the relationship between the density and temperature of newly placed hot-mix asphalt pavement, and attempts, using both field and laboratory-based data, to validate the theory that as asphalt cools it becomes denser. Hence, if a nuclear gauge is used to measure asphalt density, it should record a higher reading after the asphalt has been allowed to cool overnight than when the asphalt density was first measured just after cold rolling the previous day. This research investigation has found a model that does not reinforce this theory. Research has shown that testing a road for density the morning after paving, as opposed to the same day, does not result in a significant increase in density. In addition, this study found significant factors that impact pavement density, and developed an explanatory model to estimate pavement density.
Thermotolerance induced at a fever temperature of 40 °C protects cells against hyperthermia-induced apoptosis mediated by death receptor signalling
Authors: Bettaieb Ahmed , Averill-Bates Diana A.
Published: December 2008

Mild temperatures such as 40 °C are physiological and occur during fevers. This study determines whether mild thermotolerance induced at 40 °C can protect HeLa cells against activation of the death receptor pathway of apoptosis by lethal hyperthermia (42–45 °C). Protein expression of heat shock proteins (Hsps) 27, 32, 60, 72, 90, and 110 was increased in thermotolerant cells (3 h, 40°C). Lethal hyperthermia (42–43 °C)  caused cell death by apoptosis, but at 45 °C there was a switch to necrosis. Mild thermotolerance protected cells against heat-induced apoptosis (Annexin V labelling). Hyperthermia induced apoptosis through generation of reactive oxygen species (ROS) and death receptor signalling. The antioxidant polyethylene glycol-catalase abrogated increased expression of Fas death ligand and caspase-8 activation in response to lethal hyperthermia (42–43 °C). Mild thermotolerance attenuated the heat induction of ROS and FasL, which were initiating events in death receptor activation and signalling. Mild thermotolerance inhibited early events in hyperthermia-induced death receptor apoptosis such as Fas-associated death domain (FADD) translocation to membranes, caspase-8 activation, and tBid translocation to mitochondria. Downstream events in apoptosis such as caspase-3 activation, cleavage of PARP and ICAD, and chromatin condensation were also diminished in thermotolerant cells. It is important to improve knowledge about adaptive responses induced by exposure to mild stresses, such as fever temperatures, which can protect cells against subsequent exposure to lethal stress.
Meal-induced insulin sensitization and its parasympathetic regulation in humans
Authors: Patarrão Rita S. , Lautt W. Wayne , Afonso Ricardo A. , Ribeiro Rogério T. , Guarino Maria P. , Fernandes Ana B. , Boavida José M. , Macedo M. Paula
Published: December 2008

In animal studies, the whole-body glucose disposal effect of insulin is low in the fasted state or after atropine infusion, but doubles after a meal, consistent with the hepatic insulin-sensitizing substance (HISS) hypothesis. We tested how a standardized test meal and atropine affected the dynamic response to insulin in humans. Insulin sensitivity was assessed in healthy male subjects (aged 28.9 ± 1.9 years, body mass index 23.3 ± 0.8 kg·m–2) by using the rapid insulin sensitivity test (RIST), which is a transient euglycemic clamp. After a 24-hour fasting period, dynamic insulin sensitivity was assessed and then repeated 100 min after the test meal. In a second protocol, the volunteers were fed the standardized test meal and intravenous atropine (0.5 mg) or saline (control group) was administered 50 min before insulin sensitivity assessment. Insulin sensitivity increased in the fed state (232.1% ± 46.3%, n = 7) in comparison with the 24-hour fasted state. In the atropine protocol, the drug partially blocked (56.5% ± 11.6%, n = 6) insulin sensitivity. In humans, feeding resulted in increased insulin sensitivity. The low dose of atropine in humans lead to a partial HISS-dependent decrease in insulin sensitivity. Meal-induced insulin sensitization occured in humans by a similar mechanism as that reported in other species. The sensitization process was regulated by a cholinergic ‘feeding signal.’
Behavioral responses of white-tailed deer subjected to lethal management
Authors: Williams Scott C. , DeNicola Anthony J. , Ortega Isaac M.
Published: December 2008

Currently, the most effective and cost-efficient mechanism for controlling overabundant white-tailed deer ( Odocoileus virginianus (Zimmermann, 1780)) is lethal removal, most commonly controlled hunting and sharpshooting. Deer subjected to such efforts may behave differently during removal and remaining deer may alter behaviors, potentially limiting future efficacy of removal efforts. Our objectives were to quantify changes in deer distribution in response to controlled hunting and sharpshooting. We immobilized two sample populations of 20 deer (one enclosed and one free-ranging) in central New Jersey, USA, and fitted them with global positioning system collars. The free-ranging herd experienced 11 days of controlled hunting, reducing density from 78 to 27 deer/km2. We subjected the enclosed herd to a 7 day sharpshoot, reducing density from 83 to 7 deer/km2. Hunted deer increased mean home ranges during removal, while deer exposed to sharpshooting did not. Collared doe–doe home-range overlap increased postsharpshoot, suggesting increased social interaction. Behaviors of hunted deer were directly affected by the human threat, while behavioral changes of deer exposed to sharpshooting were linked to population reduction. In the absence of an intact matrilineal social group, unrelated does will seek each other out in what appears to be an inherent need to be social.
Determinants of seasonal variation in activity patterns of mouflon
Authors: Bourgoin G. , Garel M. , Van Moorter B. , Dubray D. , Maillard D. , Marty E. , Gaillard J.-M.
Published: December 2008

Balancing energetic requirements is a complex process governed by the current condition of the animal, its physiological state, and by the local environment. In response to these factors, animals are expected to adapt their activity patterns. Based on continuous monitoring of 14 GPS-collared animals in southern France, we studied how environmental conditions and reproductive life-cycle periods shape the monthly activity patterns of free-ranging female mouflon ( Ovis gmelini musimon  × Ovis sp. (Blyth, 1841)). More specifically, we analyzed total daily activity, diurnal activity, length of activity bouts, and number of activity bouts. We performed multivariate analyses to account for the relationship between several intercorrelated explanatory variables and monthly activity variables. Mouflon decreased their daily activity, diurnal activity, and length of activity bouts during the hot summer months. Such changes might allow animals to reduce thermoregulation costs. The resulting higher activity in winter compared with summer indicates that summer is the most limiting period for large herbivores in Mediterranean area. Both the number of active bouts and the daily activity increased during spring, when females have access to increased food quality, which ensures a faster digestion, and when they may face high energetic requirements owing to reproduction.
COMPARISON OF TRANSIENT BALLISTIC ELECTRON TRANSPORT IN BULK WURTZITE PHASE 6H-SiC and GaN
Authors: ARABSHAHI H.
Published: December 2008

An ensemble Monte Carlo simulation is used to compare bulk electron ballistic transport in 6H - SiC and GaN materials. Electronic states within the conduction band valleys at Γ1, U, M, Γ3, and K are represented by nonparabolic ellipsoidal valleys centered on important symmetry points of the Brillouin zone. The large optical phonon energy (~120 meV) and the large intervalley energy separation between the Γ and satellite conduction band valleys suggest an increasing role for ballistic electron effects in 6H - SiC , especially when compared with most III-V semiconductors such as GaAs . Transient velocity overshoot has been simulated, with the sudden application of fields up to ~5×107 Vm -1, appropriate to the gate-drain fields expected within an operational field effect transistor.

A peak-saturation drift velocity ratio of 2:1 is predicted for 6H - SiC material while that for GaN is 4:1. The electron drift velocity relaxes to the saturation value of ~2×105 ms -1 within 3 ps, for both crystal structures. The transient velocity overshoot characteristics are in fair agreement with other recent calculations.
EFFECT OF TRAP STATES AT THE OXIDE-SILICON INTERFACE IN POLYCRYSTALLINE SILICON THIN-FILM TRANSISTORS
Authors: GUPTA NAVNEET
Published: December 2008

This work presents the study of the effect of trap states at the oxide-silicon interface in lightly doped polycrystalline silicon thin-film transistors with large grains. In this study, it is assumed that the oxide-silicon interface traps are evenly distributed throughout the interface region and single grain boundary is present in the channel of poly-Si TFT. It is shown that improved device characteristics can be obtained by reducing the gate oxide thickness. It is also observed that as gate oxide thickness decreases for a constant value of trap state density in the oxide-silicon interface, the gate voltage required for channel formation is lowered and leads to a decrease in threshold voltage of the device. Calculated and experimental results are also found to be well consistent with each other.
EQUATIONS OF STATE FOR FLUIDS: THE LIQUID-VAPOR EQUILIBRIUM (LVE)
Authors: TIAN JIANXIANG , GUI YUANXING
Published: December 2008

Historically, the development of equations of state for fluids has almost invariably followed the lead of the van der Waals (vdW) equation which includes an attraction term and a repulsion term. In this paper, using a simple statistical mechanics model, we introduce a parameter σ as both the power and a coefficient of the packing fraction y which locates at the numerator of the vdW attraction term. Then nine equations of state are constructed to solve the critical conditions and the main thermodynamic properties of pure substances at liquid-vapor equilibrium. As a result, the correct critical compressibility factors of Nitrogen, Argon, Carbon dioxide, Ethene, Methane, Oxygen, Propene, Water and Hydrogen, are obtained with an optimal choice of parameter σ. Good predictions of these equations to the liquid-vapor equilibrium properties below critical temperature are reported and compared with experimental data.
SLIVER REMOVAL BY LATTICE REFINEMENT
Authors: LABELLE FRANÇOIS
Published: December 2008

I present an algorithm that can create a mesh that is free of slivers away from the boundary, or that can eliminate such slivers from a pre-existing mesh by refining it. The resulting tetrahedra have dihedral angles between 30 and 135 degrees and radius-edge ratios of at most 1.368, except near the boundary. In comparison, previous bounds on dihedral angles were microscopic. The final mesh can respect specified input vertices and a user-defined sizing function. The algorithm comes with a bound on the sizes of the features it creates, and can provably grade from small to large tetrahedra.
mCell: Facilitating Mobile Communication of Small Groups
Authors: Virtanen Jyri , Haveri Merja , Blom Jan , Häkkilä Jonna , Tarkiainen Mikko T.
Published: December 2008

Mobile communication technology offers a potential platform for new types of communication applications. Here, we describe the development and experiences with a mobile group communication application, mCell, that runs on a mobile phone. We present the underlying design implications, the application implementation, and a user study, where three groups used the application for one month. The findings of the user study reveal general user experiences with the application and show different patterns of usage depending on the social setting of the group and how the preferred features vary accordingly.
Breast Cancer–Associated Fibroblasts Confer AKT1-Mediated Epigenetic Silencing of Cystatin M in Epithelial Cells
Authors: Lin Huey-Jen L. , Zuo Tao , Lin Ching-Hung , Kuo Chieh Ti , Liyanarachchi Sandya , Sun Shuying , Shen Rulong , Deatherage Daniel E. , Potter Dustin , Asamoto Lisa , Lin Shili , Yan Pearlly S. , Cheng Ann-Lii , Ostrowski Michael C. , Huang Tim H.-M.
Published: December 2008

The interplay between histone modifications and promoter hypermethylation provides a causative explanation for epigenetic gene silencing in cancer. Less is known about the upstream initiators that direct this process. Here, we report that the Cystatin M (CST6) tumor suppressor gene is concurrently down-regulated with other loci in breast epithelial cells cocultured with cancer-associated fibroblasts (CAF). Promoter hypermethylation of CST6 is associated with aberrant AKT1 activation in epithelial cells, as well as the disabled INNP4B regulator resulting from the suppression by CAFs. Repressive chromatin, marked by trimethyl-H3K27 and dimethyl-H3K9, and de novo DNA methylation is established at the promoter. The findings suggest that microenvironmental stimuli are triggers in this epigenetic cascade, leading to the long-term silencing of CST6 in breast tumors. Our present findings implicate a causal mechanism defining how tumor stromal fibroblasts support neoplastic progression by manipulating the epigenome of mammary epithelial cells. The result also highlights the importance of direct cell-cell contact between epithelial cells and the surrounding fibroblasts that confer this epigenetic perturbation. Because this two-way interaction is anticipated, the described coculture system can be used to determine the effect of epithelial factors on fibroblasts in future studies. [Cancer Res 2008;68(24):10257–66]
Altered Detoxification Status and Increased Resistance to Oxidative Stress by K-Ras Transformation
Authors: Recktenwald Christian V. , Kellner Roland , Lichtenfels Rudolf , Seliger Barbara
Published: December 2008

Mutated K-ras is frequently found in human malignancies and plays a key role in many signal transduction processes resulting in an altered gene and/or protein expression pattern. Proteins controlled by a constitutive activated mitogen-activated protein kinase pathway are primarily related to alterations in the mitochondrial and nuclear compartments. Therefore, different K-Ras mutants and respective control cells were subjected to two-dimensional gel electrophoresis using basic pH gradients. This approach led to the identification of differentially expressed proteins, such as members of the heterogeneous ribonucleoprotein family, and enzymes involved in cellular detoxification as well as in oxidative stress. Increased expression of these enzymes was paralleled by an elevated tolerance of K-ras mutants against the cytotoxic potential of hydrogen peroxide and formaldehyde as well as an altered redox status based on enhanced intracellular glutathione (GSH) levels indicating an improved detoxification potential of defined K-ras transfectants, whereas down-regulation by RNA interference of candidate proteins reversed the tolerance against these compounds. This hypothesis is supported by an up-regulated expression of a key enzyme of the pentose phosphate pathway resulting in an increased production of NADPH required for anabolic processes as well as the rebuilding of oxidized GSH. Both the enhanced resistance against xenobiotic compounds as well as an altered oxidative pathway might confer growth advantages for tumor cells carrying dominant-positive K-ras mutations such as in lung or pancreatic adenocarcinoma. [Cancer Res 2008;68(24):10086–93]
Common Transcriptional Signature of Tumor-Infiltrating Mononuclear Inflammatory Cells and Peripheral Blood Mononuclear Cells in Hepatocellular Carcinoma Patients
Authors: Sakai Yoshio , Honda Masao , Fujinaga Haruo , Tatsumi Isamu , Mizukoshi Eishiro , Nakamoto Yasunari , Kaneko Shuichi
Published: December 2008

Hepatocellular carcinoma (HCC) is frequently associated with infiltrating mononuclear inflammatory cells. We performed laser capture microdissection of HCC-infiltrating and noncancerous liver-infiltrating mononuclear inflammatory cells in patients with chronic hepatitis C (CH-C) and examined gene expression profiles. HCC-infiltrating mononuclear inflammatory cells had an expression profile distinct from noncancerous liver-infiltrating mononuclear inflammatory cells; they differed with regard to genes involved in biological processes, such as antigen presentation, ubiquitin-proteasomal proteolysis, and responses to hypoxia and oxidative stress. Immunohistochemical analysis and gene expression databases suggested that the up-regulated genes involved macrophages and Th1 and Th2 CD4 cells. We next examined the gene expression profile of peripheral blood mononuclear cells (PBMC) obtained from CH-C patients with or without HCC. The expression profiles of PBMCs from patients with HCC differed significantly from those of patients without HCC (P < 0.0005). Many of the up-regulated genes in HCC-infiltrating mononuclear inflammatory cells were also differentially expressed by PBMCs of HCC patients. Analysis of the commonly up-regulated or down-regulated genes in HCC-infiltrating mononuclear inflammatory cells and PBMCs of HCC patients showed networks of nucleophosmin, SMAD3, and proliferating cell nuclear antigen that are involved with redox status, the cell cycle, and the proteasome system, along with immunologic genes, suggesting regulation of anticancer immunity. Thus, exploring the gene expression profile of PBMCs may be a surrogate approach for the assessment of local HCC-infiltrating mononuclear inflammatory cells. [Cancer Res 2008;68(24):10267–79]
Somatostatin Receptor sst2 Decreases Cell Viability and Hormonal Hypersecretion and Reverses Octreotide Resistance of Human Pituitary Adenomas
Authors: Acunzo Julie , Thirion Sylvie , Roche Catherine , Saveanu Alexandru , Gunz Ginette , Germanetti Anne Laure , Couderc Bettina , Cohen Richard , Figarella-Branger Dominique , Dufour Henry , Brue Thierry , Enjalbert Alain , Barlier Anne
Published: December 2008

In human somatotroph adenomas, growth hormone (GH) hypersecretion can be inhibited by somatostatin analogues such as octreotide. Unfortunately, serum GH levels reach normal values in only 60% of treated patients. The decreased sensitivity to octreotide is strongly related to a lower expression of somatostatin receptor sst2. In this present study, the sst2 gene was transferred by an adenoviral vector (Ad-sst2) in human somatotroph (n = 7) and lactotroph (n = 2) adenomas in vitro. Sst2 mRNA levels and sst2 immunostaining dramatically increased after infection. Ten days after infection at 20 multiplicity of infection (MOI), sst2 gene transfer decreased cell viability from 19% to 90% by caspase-dependent apoptosis. At low viral doses (5 MOI), Ad-sst2 decreased GH or prolactin (PRL) basal secretion and mRNA expression. Somatotroph tumors were classified in three groups according to their octreotide sensitivity. Four days after infection by 5 MOI Ad-sst2, the maximal GH suppression by octreotide increased from 31% to 57% in the octreotide partially resistant group and from 0% to 27% in the resistant ones. In the octreotide-sensitive group, EC50 values significantly decreased from 1.3 × 10−11 to 6.6 × 10−13 mol/L without improving maximal GH suppression. Finally, lactotroph tumors, nonresponding to octreotide in basal conditions, became octreotide sensitive with a maximal PRL suppression of 43% at 10−8 mol/L. Therefore, sst2 reexpression is able to improve octreotide sensitivity. Sst2 gene transfer may open new theapeutic strategies in treatment combined with somatostatin analogues. [Cancer Res 2008;68(24):10163–70]
Timosaponin A-III Induces Autophagy Preceding Mitochondria-Mediated Apoptosis in HeLa Cancer Cells
Authors: Sy Lai-King , Yan Siu-Cheong , Lok Chun-Nam , Man Ricky Y.K. , Che Chi-Ming
Published: December 2008

Timosaponin A-III (TAIII), a saponin isolated from the rhizome of Anemarrhena asphodeloides, exhibits potent cytotoxicity and has the potential to be developed as an anticancer agent. Here, we provide evidence that TAIII induces autophagy in HeLa cells followed by apoptotic cell death. TAIII-induced autophagy was morphologically characterized by the formation of membrane-bound autophagic vacuoles recognizable at the ultrastructural level. TAIII-treated cells expressing green fluorescent protein (GFP)–labeled microtubule-associated protein 1 light chain 3 (LC3) displayed punctate fluorescence indicative of LC3 recruitment to the autophagosome. This was associated with the conversion of LC3-I (the cytosolic form) into LC3-II (the lipidated form located on the autophagosome membrane). TAIII treatment also induced mitochondrial dysfunction involving overproduction of reactive oxygen species and reduction of mitochondrial membrane potential accompanied by induction of mitochondrial permeability transition. Prolonged exposure to TAIII resulted in cytochrome c release and caspase-3 activation, events that signified the onset of apoptotic cell death. TAIII-induced autophagy preceded apoptosis, as evidenced by early autophagic vacuole formation, GFP-LC3 translocation, and LC3-II increase in the absence of caspase-3 cleavage. Notably, TAIII-mediated apoptotic cell death was potentiated by treatment with autophagy inhibitor 3-methyladenine or small interfering RNA against the autophagic gene beclin 1. These findings suggest that TAIII-elicited autophagic response plays a protective role that impedes the eventual cell death. In terms of structure-activity relationship, the sugar chain in TAIII is indispensable to the drug action, as the sugar-lacking aglycone sarsasapogenin did not induce autophagy and exhibited weaker cytotoxicity. [Cancer Res 2008;68(24):10229–37]
Overexpression of OATP1B3 Confers Apoptotic Resistance in Colon Cancer
Authors: Lee Wooin , Belkhiri Abbes , Lockhart A. Craig , Merchant Nipun , Glaeser Hartmut , Harris Elizabeth I. , Washington M. Kay , Brunt Elizabeth M. , Zaika Alex , Kim Richard B. , El-Rifai Wael
Published: December 2008

Organic anion transporting polypeptide 1B3 (OATP1B3, SLCO1B3) is normally expressed in hepatocytes. In this study, we showed frequent overexpression of OATP1B3 in colorectal adenocarcinomas. Quantitative reverse transcription-PCR analysis of 17 colon tumors indicated tumoral overexpression of OATP1B3 by ∼100-fold, compared with 20 normal colon samples (P < 0.0001). Using immunohistochemistry on a tissue microarray containing 93 evaluable colon tumor specimens, we detected immunostaining of OATP1B3 in 75 colon adenocarcinomas (81%) and no immunostaining in normal samples. To determine the functional effects of OATP1B3 expression on drug-induced apoptosis, we used camptothecin and oxaliplatin on a panel of colorectal cancer cell lines stably overexpressing OATP1B3. The results indicated that OATP1B3 overexpression enhanced cell survival in RKO, HCT-8, and HCT116p53+/+ cells that harbor wild-type p53 but not in Caco-2 and HCT116p53−/− cells that lack p53, compared with the respective empty vector controls (P < 0.01). The terminal deoxynucleotidyl transferase-mediated nick-end labeling assay confirmed that HCT116p53+/+ cells overexpressing OATP1B3 had significantly lower apoptotic levels compared with empty vector control (P < 0.001). The overexpression of OATP1B3 reduced the transcriptional activity of p53, with subsequent reductions in transcript and protein levels of its downstream transcription targets (P21WAF1 and PUMA). Overexpression of a point mutation (G583E) variant of OATP1B3 lacking transport activity did not confer an antiapoptotic effect or affect p53 transcriptional activity, suggesting that the antiapoptotic effect of OATP1B3 may be associated with its transport activity. Taken together, our results suggest that OATP1B3 overexpression in colorectal cancer cells may provide a survival advantage by altering p53-dependent pathways. [Cancer Res 2008;68(24):10315–23]
A Transcription-Independent Function of FOXO1 in Inhibition of Androgen-Independent Activation of the Androgen Receptor in Prostate Cancer Cells
Authors: Liu Ping , Li Shangwei , Gan Lu , Kao Timothy P. , Huang Haojie
Published: December 2008

Increasing evidence suggests that aberrant activation of the androgen receptor (AR) plays a pivotal role in the development and progression of androgen depletion–independent prostate cancer (PCa) after androgen deprivation therapy. Here, we show that loss of the PTEN tumor suppressor gene is associated with hyperactivation of the AR in human PCa cell lines. This effect is mediated primarily by its downstream effector FOXO1. In addition to the inhibition of androgenic activation of the AR, forced expression of FOXO1 in PTEN-negative PCa cells also inhibits androgen-independent activation of the AR in a manner independent of FOXO1 transcriptional function. In contrast, silencing of FOXO1 in PTEN-positive cells not only increases the basal activity of the AR in the absence of androgens, it also markedly sensitizes the AR activation by low levels of androgens or nonandrogenic factors such as interleukin-6. FOXO1-mediated inhibition of the AR is partially attenuated by the histone deacetylase (HDAC) inhibitor trichostatin A. Accordingly, FOXO1 interacts with HDAC3 as shown by coimmunoprecipitation assays, and cotransfection of cells with FOXO1 and HDAC3, but not HDAC1 and HDAC2, results in a greater inhibition of AR activity than in cells transfected with FOXO1 or HDAC3 individually. Together, our findings define a novel corepressor function of FOXO1 in inhibition of androgen-independent activation of the AR. [Cancer Res 2008;68(24):10290–9]
Molecular Mechanisms of Patupilone Resistance
Authors: Mozzetti Simona , Iantomasi Raffaella , De Maria Ilaria , Prislei Silvia , Mariani Marisa , Camperchioli Alessia , Bartollino Silvia , Gallo Daniela , Scambia Giovanni , Ferlini Cristiano
Published: December 2008

Patupilone is an epothilone in advanced clinical development that has shown promising efficacy in heavily pretreated patients. This study aimed at characterizing the mechanisms of patupilone activity in resistant patients. To this end, we generated patupilone-resistant cells using two cellular models, the first characterized by high chemosensitivity and low class III β-tubulin (TUBB3) expression (A2780), and the second by low chemosensitivity and high TUBB3 expression (OVCAR-3). The obtained cell lines were named EPO3 and OVCAR-EPO, respectively. The same selection procedure was done in A2780 cells to generate a paclitaxel-resistant cell line (TAX50). Factors of resistance are expected to increase in the drug-resistant cell lines, whereas factors of drug sensitivity will be down-regulated. Using this approach, we found up-regulation of TUBB3 in TAX50, but not EPO3, cells, showing that TUBB3 mediates the resistance to paclitaxel but not to patupilone. Moreover, TUBB3 was a factor of patupilone sensitivity because OVCAR-EPO cells exhibited a dramatic reduction of TUBB3 and a concomitant sensitization to hypoxia and cisplatin-based chemotherapy. To identify the mechanisms underlying patupilone resistance, tubulin genes were sequenced, thereby revealing that a prominent mechanism of drug resistance is represented by point mutations in class I β-tubulin. Overall, these results suggest that paclitaxel and patupilone have nonoverlapping mechanisms of resistance, thus allowing the use of patupilone for those patients relapsing after paclitaxel-based chemotherapy. Furthermore, patupilone represents a promising first-line option for the treatment of high-risk ovarian cancer patients, who exhibit high TUBB3 levels and poor response to standard paclitaxel-platin chemotherapy. [Cancer Res 2008;68(24):10197–204]
A Mutant Collagen XIII Alters Intestinal Expression of Immune Response Genes and Predisposes Transgenic Mice to Develop B-Cell Lymphomas
Authors: Tuomisto Anne , Sund Malin , Tahkola Jenni , Latvanlehto Anne , Savolainen Eeva-Riitta , Autio-Harmainen Helena , Liakka Annikki , Sormunen Raija , Vuoristo Jussi , West Anne , Lahesmaa Riitta , Morse Herbert C. , Pihlajaniemi Taina
Published: December 2008

Epithelial cells of mucosal surfaces are critical for maintaining immune homeostasis by aiding in the discrimination of pathogenic and commensal microorganisms and modulating the activities of antigen-presenting cells and lymphocytes. Functional breakdowns resulting in chronic infection and inflammation are associated with the development of hematologic and solid neoplasms for which detailed pathogenetic mechanisms are poorly understood. Mice heterozygous for a transgene Col13a1del expressing a mutant collagen XIII developed clonal mature B-cell lineage lymphomas originating in mesenteric lymph nodes (MLN). The tumors were associated with T cells and macrophages. The incidence of disease was reduced 2-fold in transgenic mice raised under specific pathogen-free conditions, suggesting a role for infectious agents. The lymphomas did not express the mutant collagen XIII, indicating that its influence on tumorigenesis was B-cell extrinsic and likely to be associated with collagen XIII–positive tissues drained by the MLN. Studies of the small intestines of transgenic mice showed that the subepithelial basement membranes (BM) were highly abnormal and that they exhibited heightened expression of genes involved in immune responses. These results define collagen XIII–dependent maintenance of the intestinal BM as a previously unappreciated component of immune responses and a critical determinant of cancer susceptibility. [Cancer Res 2008;68(24):10324–31]
Confirmation of Gene Expression–Based Prediction of Survival in Non–Small Cell Lung Cancer
Authors: Guo Nancy L. , Wan Ying-Wooi , Tosun Kursad , Lin Hong , Msiska Zola , Flynn Daniel C. , Remick Scot C. , Vallyathan Val , Dowlati Afshin , Shi Xianglin , Castranova Vincent , Beer David G. , Qian Yong
Published: December 2008

Purpose: It is a critical challenge to determine the risk of recurrence in early stage non–small cell lung cancer (NSCLC) patients. Accurate gene expression signatures are needed to classify patients into high- and low-risk groups to improve the selection of patients for adjuvant therapy.

Experimental Design: Multiple published microarray data sets were used to evaluate our previously identified lung cancer prognostic gene signature. Expression of the signature genes was further validated with real-time reverse transcription-PCR and Western blot assays of snap-frozen lung cancer tumor tissues.

Results: Our previously identified 35-gene signature stratified 264 patients with NSCLC into high- and low-risk groups with distinct overall survival rates (P < 0.05, Kaplan-Meier analysis, log-rank tests). The 35-gene signature further stratified patients with clinical stage 1A diseases into poor prognostic and good prognostic subgroups (P = 0.0007, Kaplan-Meier analysis, log-rank tests). This signature is independent of other prognostic factors for NSCLC, including age, sex, tumor differentiation, tumor grade, and tumor stage. The expression of the signature genes was validated with real-time reverse transcription-PCR analysis of lung cancer tumor specimens. Protein expression of two signature genes, TAL2 and ILF3, was confirmed in lung adenocarcinoma tumors by using Western blot analysis. These two biomarkers showed correlated mRNA and protein overexpression in lung cancer development and progression.

Conclusions: The results indicate that the identified 35-gene signature is an accurate predictor of survival in NSCLC. It provides independent prognostic information in addition to traditional clinicopathologic criteria.
Cancer Stem Cell Analysis and Clinical Outcome in Patients with Glioblastoma Multiforme
Authors: Pallini Roberto , Ricci-Vitiani Lucia , Banna Giuseppe Luigi , Signore Michele , Lombardi Dario , Todaro Matilde , Stassi Giorgio , Martini Maurizio , Maira Giulio , Larocca Luigi Maria , De Maria Ruggero
Published: December 2008

Purpose: Cancer stem cells (CSC) are thought to represent the population of tumorigenic cells responsible for tumor development. The stem cell antigen CD133 identifies such a tumorigenic population in a subset of glioblastoma patients. We conducted a prospective study to explore the prognostic potential of CSC analysis in glioblastoma patients.

Experimental Design: We investigated the relationship between the in vitro growth potential of glioblastoma CSCs and patient death or disease progression in tumors of 44 consecutive glioblastoma patients treated with complete or partial tumorectomy followed by radiotherapy combined with temozolomide treatment. Moreover, we evaluated by immunohistochemistry and immunofluorescence the prognostic value of the relative presence of CD133+ and CD133+/Ki67+ cells in patient tumors.

Results: In vitro CSC generation and the presence of ≥2% CD133+ cells in tumor lesions negatively correlated with overall (P = 0.0001 and 0.02, respectively) and progression-free (P = 0.0002 and 0.01, respectively) survival of patients. A very poor overall (P = 0.007) and progression-free (P = 0.001) survival was observed among patients whose tumors contained CD133+ cells expressing Ki67. Taking into account symptom duration, surgery type, age, O6-methylguanine-DNA methyltransferase promoter methylation, and p53 status, generation of CSCs and CD133/Ki67 coexpression emerged as highly significant independent prognostic factors, with an adjusted hazard ratio of 2.92 (95% confidence interval, 1.37-6.2; P = 0.005) and 4.48 (95% confidence interval, 1.68-11.9; P = 0.003), respectively.

Conclusions: The analysis of CSCs may predict the survival of glioblastoma patients. In vitro CSC generation and presence of CD133+/Ki67+ cells are two considerable prognostic factors of disease progression and poor clinical outcome.
Effects of High-Dose IFNα2b on Regional Lymph Node Metastases of Human Melanoma: Modulation of STAT5, FOXP3, and IL-17
Authors: Wang Wenjun , Edington Howard D. , Rao Uma N.M. , Jukic Drazen M. , Radfar Arash , Wang Hong , Kirkwood John M.
Published: December 2008

Purpose: Signal transducer and activator of transcription 5 (STAT5) and STAT3 oppose one another in regulation of the reciprocal development of CD4+CD25+FOXP3+ regulatory T cells (Treg) and T helper 17 (Th17). A reduction in STAT3 is associated with up-regulation of Treg, and STAT5 activation promotes Treg differentiation or function while constraining Th17 generation. The effects of IFNα on STAT signaling in relation to tumor tissue Treg and Th17 have not been documented in humans beyond the observations that IFNα2b down-regulates STAT3.

Experimental Design: Following diagnostic biopsy and before definitive surgery, 20 doses of high-dose IFNα2b (HDI) were administered to patients with stage IIIB melanoma who gave written informed consent. Lymph node biopsies, in which both total STAT3 and phosphorylated STAT3 were down-regulated by HDI, were probed with STAT5, FOXP3, CD4, and interleukin 17 (IL-17) with immunohistochemistry and/or immunofluorescence techniques.

Results: The percentage of FOXP3+ lymphocytes determined by immunohistochemistry was up-regulated from 3.06 ± 0.65% to 9.86 ± 1.27% (n = 13, P = 0.0002), and this observation was confirmed by immunofluorescence evaluation of CD4+FOXP3+ Tregs. HDI induced STAT5 up-regulation (five cases observed) in melanoma cells and lymphocytes but did not induce the generation of IL-17–expressing lymphocytes. Increased STAT5 expression was associated with increased FOXP3 expression among lymphocytes, and STAT5 was constitutively activated among both melanoma cells and lymphocytes.

Conclusion: IFNα2b up-regulates STAT5 and down-regulates STAT3, in conjunction with up-regulation of Treg and inhibition of IL-17–expressing lymphocytes in melanoma tissues. These findings suggest that the effects of IFNα may be potentiated through interference with the response of Tregs and/or STAT5.