bluuebunny/crossref_metadata_2025 huggingface dataset:
North Korea and the US State Sponsors of Terrorism List*
Authors: Roehrig Terence
Published: March 2009

On 11 October 2008, the Bush administration removed North Korea from the State Department's list of states that sponsor terrorism. Pyongyang had been on the list since 1988 and was placed there after the November 1987 bombing of Korean Airlines flight 858 over the Andaman Sea. Though North Korea went on the list for terrorist actions, its removal became part of the Six‐Party process to convince Pyongyang to forgo its nuclear weapons ambitions. This article will explore these issues and examine the leverage the terrorism list had on North Korean behavior, how the USA chose to utilize that leverage, and North Korea's response to US efforts. This article argues that the intertwining of the terrorism list with denuclearization gave the USA leverage in the Six‐Party Talks but there were limits to what this leverage could gain. Moreover, the links to the denuclearization process also generated leverage for North Korea that it exercised, creating a more complex and crosscutting mix of costs and incentives that was more difficult for Washington to control.
The affine part of the Picard scheme
Authors: Geisser Thomas
Published: March 2009

We describe the maximal torus and maximal unipotent subgroup of the Picard variety of a proper scheme over a perfect field.
Formule du conducteur pour un caractère l-adique
Authors: Vidal Isabelle
Published: March 2009

LetKbe a local field of equal characteristicp>2, letXK/Kbe a smooth proper relative curve, and letbe a rank 1 smoothl-adic sheaf (l≠p) on a dense open subsetUKXK. In this paper, under some assumptions on the wild ramification of, we prove a conductor formula that computes the Swan conductor of the etale cohomology of the vanishing cycles of. Our conductor formula is a generalization of the conductor formula of Bloch, but for non-constant coefficients.
On manifolds with quadratic curvature decay
Authors: Yeganefar Nader
Published: March 2009

We give conditions which imply that a complete noncompact manifold with quadratic curvature decay has finite topological type. In particular, we find links between the topology of a manifold with quadratic curvature decay and some properties of the asymptotic cones of such a manifold.
Validation of tissue microarray technology in malignant peripheral nerve sheath tumours
Authors: Cunha K Soares Gonçalves , Caruso A Cunha , Gonçalves A Soares , Bernardo V Gonçalves , Pires A Rodrigues Cordovil , da Fonseca E Carvalho , de Faria P Antônio Silvestre , da Silva L Esmeraldo , Geller M , de Moura-Neto R Soares , Lopes V Silami
Published: March 2009

Background:

It has been suggested that the donor tissue cores used in tissue microarrays (TMAs) may not be representative of the whole tissue section.

Aim:

To validate the use of TMA technology in the study of malignant peripheral nerve sheath tumours (MPNSTs).

Methods:

A TMA was constructed containing five independent core biopsy samples of 14 formalin-fixed, paraffin-embedded MPNSTs. The immunohistochemical (IHC) results of the five cores from the same tissue block on TMA were compared with readings from whole sections using two antibodies: anti-Ki-67 and anti-S-100. Digital image analysis was performed to calculate the percentage of positive stain areas. The agreement between IHC results obtained with TMA cores and whole sections was assessed using the κ statistic.

Results:

There was good to very good agreement between IHC results for whole and TMA sections from MPNSTs. In relation to S-100, very good agreement (92% agreement; κ = 0.77) was observed using a minimum of four TMA cores. Staining results for Ki-67 from at least four readable TMA cores were the same as those for the whole section in 86% of cases, with good agreement, using weighted κ statistics (κ = 0.63).

Conclusions:

This study indicates that the TMA technique can be used in the IHC study of MPNSTs, even with the use of heterogeneous markers such as S-100 protein.
ASYMPTOTIC EXPANSIONS FOR PERIOD DEFORMATIONS OF MULTIPLE HURWITZ ZETA FUNCTIONS AND THEIR ASSOCIATED FUNCTIONS
Authors: ONODERA KAZUHIRO
Published: March 2009

We study the asymptotic behavior of multiple Hurwitz zeta functions and generalized multiple gamma and sine functions as some period parameters tend to 0. We obtain the perfect asymptotic expansions and get some applications in refining a previous paper by the author.
A REPRESENTATION THEOREM FOR LOCALLY COMPACT QUANTUM GROUPS
Authors: JUNGE MARIUS , NEUFANG MATTHIAS , RUAN ZHONG-JIN
Published: March 2009

Recently, Neufang, Ruan and Spronk proved a completely isometric representation theorem for the measure algebra M(G) and for the completely bounded (Herz–Schur) multiplier algebra McbA(G) on [Formula: see text], where G is a locally compact group. We unify and generalize both results by extending the representation to arbitrary locally compact quantum groups 𝔾 = (M, Γ, φ, ψ). More precisely, we introduce the algebra [Formula: see text] of completely bounded right multipliers on L1(𝔾) and we show that [Formula: see text] can be identified with the algebra of normal completely bounded [Formula: see text]-bimodule maps on [Formula: see text] which leave the subalgebra M invariant. From this representation theorem, we deduce that every completely bounded right centralizer of L1(𝔾) is in fact implemented by an element of [Formula: see text]. We also show that our representation framework allows us to express quantum group "Pontryagin" duality purely as a commutation relation.
CYCLOTOMIC EXPANSION OF EXCEPTIONAL SPECTRAL MEASURES
Authors: BANICA TEODOR
Published: March 2009

We find explicit formulae for the circular spectral measures of E7, E8. This leads to a number of general observations regarding the ADE circular measures: these are linear combinations of measures supported by the roots of unity, with real density given by certain degree 3 polynomials.
FREE BROWNIAN MOTION AND EVOLUTION TOWARDS ⊞-INFINITE DIVISIBILITY FOR k-TUPLES
Authors: BELINSCHI SERBAN T. , NICA ALEXANDRU
Published: March 2009

Let [Formula: see text] be the space of non-commutative distributions of k-tuples of self-adjoint elements in a C*-probability space. For every t ≥ 0 we consider the transformation [Formula: see text] defined by [Formula: see text] where ⊞ and ⊎ are the operations of free additive convolution and respectively of Boolean convolution on [Formula: see text]. We prove that 𝔹s◦ 𝔹t= 𝔹s + t, for all s, t ≥ 0. For t = 1, we prove that [Formula: see text] is precisely the set [Formula: see text] of distributions in [Formula: see text] which are infinitely divisible with respect to ⊞, and that the map [Formula: see text] coincides with the multi-variable Boolean Bercovici–Pata bijection put into evidence in our previous paper [1]. Thus for a fixed [Formula: see text], the process {𝔹t(μ)|t ≥ 0} can be viewed as some kind of "evolution towards ⊞-infinite divisibility".

On the other hand, we put into evidence a relation between the transformations ⊞tand free Brownian motion. More precisely, we introduce a map [Formula: see text] which transforms the free Brownian motion started at an arbitrary [Formula: see text] into the process {𝔹t(μ)|t ≥ 0} for μ = Φ(ν).
ON THE MARKOV TRACE FOR TEMPERLEY–LIEB ALGEBRAS OF TYPE En
Authors: GREEN R. M.
Published: March 2009

We show that there is a unique Markov trace on the tower of Temperley–Lieb type quotients of Hecke algebras of Coxeter type En(for all n ≥ 6). We explain in detail how this trace may be computed easily using tom Dieck's calculus of diagrams. As applications, we show how to use the trace to show that the diagram representation is faithful, and to compute leading coefficients of certain Kazhdan–Lusztig polynomials.
AN ENUMERATION OF THETA-CURVES WITH UP TO SEVEN CROSSINGS
Authors: MORIUCHI HIROMASA
Published: March 2009

We enumerate all the prime θ-curves with up to seven crossings to confirm a table made by Litherland. These θ-curves are mutually distinguished by the Yamada polynomial.
SOLUTION OF THE HURWITZ PROBLEM FOR LAURENT POLYNOMIALS
Authors: PAKOVICH F.
Published: March 2009

We investigate the following existence problem for rational functions: for a given collection Π of partitions of a number n to define whether there exists a rational function f of degree n for which Π is the branch datum. An important particular case when the answer is known is the one when the collection Π contains a partition consisting of a single element (in this case, the corresponding rational function is equivalent to a polynomial). In this paper, we provide a solution in the case when Π contains a partition consisting of two elements.
ON MAXIMAL COLLECTIONS OF ESSENTIAL ANNULI IN A HANDLEBODY II
Authors: YIN XUNBO , TANG JINGYAN , LEI FENGCHUN
Published: March 2009

It is known that a maximal collection of essential annuli in H2 could contain exactly 1, or 2, or at most 3 annuli, and a maximal collection of essential annuli in Hn with n ≥ 3 can contains at most 4n - 5 annuli, and the bound is best possible. In the present paper, we show that a maximal collection of essential annuli in Hn with n ≥ 3 contains at least two annuli, and for each m, 2 ≤ m ≤ 4n - 5, there exists a maximal collection of essential annuli in Hn which contains exactly m annuli.
ENTREPRENEURSHIP EDUCATION AND TRAINING IN A SMALL BUSINESS CONTEXT: INSIGHTS FROM THE COMPETENCE-BASED APPROACH
Authors: LANS THOMAS , HULSINK WIM , BAERT HERMAN , MULDER MARTIN
Published: March 2009

The concept of competence, as it is brought into play in current research, is a potentially powerful construct for entrepreneurship education and training research and practice. Although the concept has been the subject of strong debate in educational research in general, critical analysis of how it has been used, applied and experienced in entrepreneurship education practice is scarce. This article contributes specifically to the discussion of entrepreneurial competence by theoretically unfolding and discussing the concept. Subsequently, the implications of applying a competence-based approach in entrepreneurship education are illustrated and discussed based on analysis of two cases that were aimed at identifying, diagnosing and eventually developing entrepreneurial competence in small businesses in the Netherlands and Flanders (Belgium). The cases show that the added value of focussing on competence in entrepreneurship education and training lies in making the (potential) small business owner aware of the importance of certain entrepreneurial competencies and in providing direction for competence development. In this process it is fundamental that competence is treated as an item for discussion and interpretation, rather than as a fixed template of boxes to be ticked. Furthermore the cases highlight that a competence-based approach does not completely determine the type of educational and instructional strategies to be used. Its consequential power in that respect is limited.
SOCIAL ENTREPRENEURSHIP: A GROUNDED LEARNING APPROACH TO SOCIAL VALUE CREATION
Authors: SMITH BRETT R. , BARR TERRI FELDMAN , BARBOSA SAULO D. , KICKUL JILL R.
Published: March 2009

The value of the inclusion of social entrepreneurship in entrepreneurship education courses and programs is considered in light of the increase in social entrepreneurial ventures worldwide as well as changing business school requirements. Using a grounded learning theory approach as a foundation, we consider factors unique to social entrepreneurship and present a live case social venture which provides hands-on experience to students. Student comments regarding their learning through this experience are also included. Future directions for social entrepreneurship education pedagogy and research are discussed.
HYPERBOLIC SMOOTHING EFFECT FOR SEMILINEAR WAVE EQUATIONS AT A FOCAL POINT
Authors: LIANG JIANFENG
Published: March 2009

For semi-linear dissipative wave equation □u + |ut|p - 1ut = 0, we consider finite energy solutions with singularities propagating along a focusing light cone. At the tip of cone, the singularities are focused and partially smoothed out under strong nonlinear dissipation, i.e. the solution gets up to 1/2 more L2 derivative after the focus. The smoothing phenomenon is in fact the result of simultaneous action of focusing and nonlinear dissipation.
THE SOLUTION OF THE CAUCHY PROBLEM WITH LARGE DATA FOR A MODEL OF A MIXTURE OF GASES
Authors: HOLDEN HELGE , RISEBRO NILS HENRIK , SANDE HILDE
Published: March 2009

In this paper, we study mixture of gases, each governed by a gamma law. The system is modeled by the p-system with variable gamma. We use this model to study immiscible gas flow. The main result is that the Cauchy problem with large data is shown to have a solution. We use the Glimm scheme for the proof. The result is illustrated by numerical examples.
A FULLY PSEUDOSPECTRAL SCHEME FOR SOLVING SINGULAR HYPERBOLIC EQUATIONS ON CONFORMALLY COMPACTIFIED SPACE-TIMES
Authors: HENNIG JÖRG , ANSORG MARCUS
Published: March 2009

With the example of the spherically symmetric scalar wave equation on Minkowski space-time we demonstrate that a fully pseudospectral scheme (i.e. spectral with respect to both spatial and time directions) can be applied for solving hyperbolic equations. The calculations are carried out within the framework of conformally compactified space-times. In our formulation, the equation becomes singular at null infinity and yields regular boundary conditions there. In this manner, it becomes possible to avoid "artificial" conditions at some numerical outer boundary at a finite distance. We obtain highly accurate numerical solutions possessing exponential spectral convergence, a feature known from solving elliptic PDEs with spectral methods. Our investigations are meant as a first step towards the goal of treating time evolution problems in General Relativity with spectral methods in space and time.
LINEAR AND NONLINEAR TAILS II: EXACT DECAY RATES IN SPHERICAL SYMMETRY
Authors: SZPAK NIKODEM , BIZOŃ PIOTR , CHMAJ TADEUSZ , ROSTWOROWSKI ANDRZEJ
Published: March 2009

We derive the exact late-time asymptotics for small spherically symmetric solutions of nonlinear wave equations with a potential. The dominant tail is shown to result from the competition between linear and nonlinear effects.
Integration of hormonal and nutrient signals that regulate leptin synthesis and secretion
Authors: Lee Mi-Jeong , Fried Susan K.
Published: March 2009

This review summarizes recent advances in our understanding of the pre- and posttranscriptional mechanisms that regulate leptin production and secretion in adipocytes. Basal leptin production is proportional to the status of energy stores, i.e., fat cell size, and this is mainly regulated by alterations in leptin mRNA levels. Leptin mRNA levels are regulated by hormones, including glucocorticoids and catecholamines, but little is known about the transcriptional mechanisms involved. Leptin synthesis and secretion is also acutely modulated in response to hormones such as insulin and the availability of metabolic fuels. Acute variations in leptin production over a time course of minutes to hours are mediated at the levels of both translation and secretion. Increases in amino acids and insulin after a meal activate the mammalian target of rapamycin (mTOR) pathway, leading to an increase in specific rates of leptin biosynthesis. Cross-talk among mTOR, PKA, and AMP-activated protein kinase pathways appears to integrate hormonal and nutrient signals that regulate leptin mRNA translation, at least in part through mechanisms involving its 5′- and 3′-untranslated regions. In addition, the rate of leptin secretion from preformed stores in response to hormonal cues is also regulated. Insulin stimulates, and adrenergic agonists inhibit, leptin secretion, and this likely contributes to variations in the magnitude of nutrition-related leptin excursions and oscillations. Overall, the study of leptin production has contributed to a deepening understanding of leptin biology and, more broadly, to our understanding of the cellular and molecular mechanisms by which the adipocyte integrates hormonal and nutrient signals to regulate adipokine production.
Rapid and Sensitive Mapping of Long-Range Connections In Vitro Using Flavoprotein Autofluorescence Imaging Combined With Laser Photostimulation
Authors: Llano D. A. , Theyel B. B. , Mallik A. K. , Sherman S. M. , Issa N. P.
Published: March 2009

We investigated the use of flavoprotein autofluorescence (FA) as a tool to map long-range neural connections and combined FA with laser-uncaging of glutamate to facilitate rapid long-range mapping in vitro. Using the somatosensory thalamocortical slice, we determined that the spatial resolution of FA is ≥100–200 μm and that the sensitivity for detecting thalamocortical synaptic activity approximates that of whole cell recording. Blockade of ionotropic glutamate receptors with DNQX and AP5 abolished cortical responses to electrical thalamic stimulation. The combination of FA with photostimulation using caged glutamate revealed robust long-distance connectivity patterns that could be readily assessed in slices from the somatosensory, auditory, and visual systems that contained thalamocortical, corticothalamic, or corticocortical connections. We mapped the projection from theventral posterior nucleus of thalamus (VPM) to the primary somatosensory cortex-barrel field and confirmed topography that had been previously described using more laborious methods. We also produced a novel map of the projections from the VPM to the thalamic reticular nucleus, showing precise topography along the dorsoventral axis. Importantly, only about 30 s were needed to generate the connectivity map (six stimulus locations). These data suggest that FA is a sensitive tool for exploring and measuring connectivity and, when coupled with glutamate photostimulation, can rapidly map long-range projections in a single animal.
Superoxide dismutase 3, extracellular (SOD3) variants and lung function
Authors: Ganguly Koustav , Depner Martin , Fattman Cheryl , Bein Kiflai , Oury Tim D. , Wesselkamper Scott C. , Borchers Michael T. , Schreiber Martina , Gao Fei , von Mutius Erika , Kabesch Michael , Leikauf George D. , Schulz Holger
Published: March 2009

Polymorphisms in Superoxide dismutase 3, extracellular ( SOD3) have been associated with reduced lung function and susceptibility to chronic obstructive pulmonary disease (COPD) in adults. Previously, we identified SOD3 as a contributing factor to altered ventilation efficiency (dead space volume/total lung capacity) in mice. Because SOD3 protects the extracellular matrix of the lung, we hypothesized that SOD3 variants also may influence postnatal lung function development. In this study, SOD3 transcript and protein localization were examined in mouse strains with differing ventilation efficiency [C3H/HeJ (high), JF1/Msf (low)] during postnatal lung development. Compared with C3H/HeJ mice, JF1/Msf mice had Sod3 promoter single nucleotide polymorphisms (SNPs) that could affect transcription factor binding sites and a decline in total lung SOD3 mRNA during postnatal development. In adult JF1/Msf mice, total lung SOD3 activity as well as SOD3 transcript and protein in airway epithelial and alveolar type II cells and the associated matrix decreased. In children ( n = 1,555; age 9–11 yr), two common SOD3 SNPs, one located in the promoter region [C/T affecting a predicted aryl hydrocarbon receptor-xenobiotic response element (AhR-XRE) binding motif] and the other in exon 2 (Thr/Ala missense mutation), were associated with decreased forced expiratory volume in 1 s (FEV1), and the promoter SNP was associated with decreased maximal expiratory flow at 25% volume (MEF25). In vitro, a SOD3 promoter region-derived oligonucleotide containing the C variant was more effective in competing with the nuclear protein-binding capacity of a labeled probe than that containing the T variant. Along with the previous associated risk of lung function decline in COPD, these findings support a possible role of SOD3 variants in determining lung function in children.
A Key Regulatory Role of the Transcription Factor NFATc2 in Bronchial Adenocarcinoma via CD8+ T Lymphocytes
Authors: Maxeiner Joachim H. , Karwot Roman , Sauer Kerstin , Scholtes Petra , Boross Ildiko , Koslowski Michael , Türeci Özlem , Wiewrodt Rainer , Neurath Markus F. , Lehr Hans A. , Finotto Susetta
Published: March 2009

The Ca2+-regulated calcineurin/nuclear factor of activated T cells (NFAT) cascade controls alternative pathways of T-cell activation and peripheral tolerance. Here, we describe reduction of NFATc2 mRNA expression in the lungs of patients with bronchial adenocarcinoma. In a murine model of bronchoalveolar adenocarcinoma, mice lacking NFATc2 developed more and larger solid tumors than wild-type littermates. The extent of central tumor necrosis was decreased in the tumors in NFATc2(−/−) mice, and this finding was associated with reduced tumor necrosis factor-α and interleukin-2 (IL-2) production by CD8+ T cells. Adoptive transfer of CD8+ T cells of NFATc2(−/−) mice induced transforming growth factor-β1 in the airways of recipient mice, thus supporting CD4+CD25+Foxp-3+glucocorticoid-induced tumor necrosis factor receptor (GITR)+ regulatory T (Treg) cell survival. Finally, engagement of GITR in NFATc2(−/−) mice induced IFN-γ levels in the airways, reversed the suppression by Treg cells, and costimulated effector CD4+CD25+ (IL-2Rα) and memory CD4+CD127+ (IL-7Rα) T cells, resulting in abrogation of carcinoma progression. Agonistic signaling through GITR, in the absence of NFATc2, thus emerges as a novel possible strategy for the treatment of human bronchial adenocarcinoma in the absence of NFATc2 by enhancing IL-2Rα+ effector and IL-7Rα+ memory-expressing T cells. [Cancer Res 2009;69(7):3069–76]
Programmed Cell Death Protein 4 Down-regulates Y-Box Binding Protein-1 Expression via a Direct Interaction with Twist1 to Suppress Cancer Cell Growth
Authors: Shiota Masaki , Izumi Hiroto , Tanimoto Akihide , Takahashi Mayu , Miyamoto Naoya , Kashiwagi Eiji , Kidani Akihiko , Hirano Gen , Masubuchi Daisuke , Fukunaka Yasushi , Yasuniwa Yoshihiro , Naito Seiji , Nishizawa Shigeru , Sasaguri Yasuyuki , Kohno Kimitoshi
Published: March 2009

Programmed cell death protein 4 (PDCD4) has recently been shown to be involved in both transcription and translation, and to regulate cell growth. However, the mechanisms underlying PDCD4 function are not well understood. In this study, we show that PDCD4 interacts directly with the transcription factor Twist1 and leads to reduced cell growth through the down-regulation of the Twist1 target gene Y-box binding protein-1 (YB-1). PDCD4 interacts with the DNA binding domain of Twist1, inhibiting its DNA binding ability and YB-1 expression. Immunohistochemical analysis showed that an inverse correlation between nuclear PDCD4 and YB-1 expression levels was observed in 37 clinical prostate cancer specimens. Growth suppression by PDCD4 expression was completely recovered by either Twist1 or YB-1 expression. Moreover, PDCD4-overexpressing cells are sensitive to cisplatin and paclitaxel but not to etoposide or 5-fluorouracil. In summary, PDCD4 negatively regulates YB-1 expression via its interaction with Twist1 and is involved in cancer cell growth and chemoresistance. [Cancer Res 2009;69(7):3148–56]
The Human Cytomegalovirus–Encoded Chemokine Receptor US28 Promotes Angiogenesis and Tumor Formation via Cyclooxygenase-2
Authors: Maussang David , Langemeijer Ellen , Fitzsimons Carlos P. , Stigter-van Walsum Marijke , Dijkman Remco , Borg Martin K. , Slinger Erik , Schreiber Andreas , Michel Detlef , Tensen Cornelis P. , van Dongen Guus A.M.S. , Leurs Rob , Smit Martine J.
Published: March 2009

The human cytomegalovirus (HCMV), potentially associated with the development of malignancies, encodes the constitutively active chemokine receptor US28. Previously, we have shown that US28 expression induces an oncogenic phenotype both in vitro and in vivo. Microarray analysis revealed differential expression of genes involved in oncogenic signaling in US28-expressing NIH-3T3 cells. In particular, the expression of cyclooxygenase-2 (COX-2), a key mediator of inflammatory diseases and major determinant in several forms of cancer, was highly up-regulated. US28 induced increases in COX-2 expression via activation of nuclear factor-κB, driving the production of vascular endothelial growth factor. Also, in HCMV-infected cells, US28 contributed to the viral induction of COX-2. Finally, the involvement of COX-2 in US28-mediated tumor formation was evaluated using the COX-2 selective inhibitor Celecoxib. Targeting COX-2 in vivo with Celecoxib led to a marked delay in the onset of tumor formation in nude mice injected with US28-transfected NIH-3T3 cells and a reduction of subsequent growth by repressing the US28-induced angiogenic activity. Hence, the development of HCMV-related proliferative diseases may partially be ascribed to the ability of US28 to activate COX-2. [Cancer Res 2009;69(7):2861–9]
14-3-3ζ Overexpression Defines High Risk for Breast Cancer Recurrence and Promotes Cancer Cell Survival
Authors: Neal Christopher L. , Yao Jun , Yang Wentao , Zhou Xiaoyan , Nguyen Nina T. , Lu Jing , Danes Christopher G. , Guo Hua , Lan Keng-Hsueh , Ensor Joe , Hittelman Walter , Hung Mien-Chie , Yu Dihua
Published: March 2009

The ubiquitously expressed 14-3-3 proteins are involved in numerous important cellular functions. The loss of 14-3-3σ is a common event in breast cancer; however, the role of other 14-3-3s in breast cancer is unclear. Recently, we found that 14-3-3ζ overexpression occurs in early stage breast diseases and contributes to transformation of human mammary epithelial cells. Here, we show that 14-3-3ζ overexpression also persisted in invasive ductal carcinoma and contributed to the further progression of breast cancer. To examine the clinical effect of 14-3-3ζ overexpression in advanced stage breast cancer, we performed immunohistochemical analysis of 14-3-3ζ expression in primary breast carcinomas. 14-3-3ζ overexpression occurred in 42% of breast tumors and was determined to be an independent prognostic factor for reduced disease-free survival. 14-3-3ζ overexpression combined with ErbB2 overexpression and positive lymph node status identified a subgroup of patients at high risk for developing distant metastasis. To investigate whether 14-3-3ζ overexpression causally promotes breast cancer progression, we overexpressed 14-3-3ζ by stable transfection or reduced 14-3-3ζ expression by siRNA in cancer cell lines. Increased 14-3-3ζ expression enhanced anchorage-independent growth and inhibited stress-induced apoptosis, whereas down-regulation of 14-3-3ζ reduced anchorage-independent growth and sensitized cells to stress-induced apoptosis via the mitochondrial apoptotic pathway. Transient blockade of 14-3-3ζ expression by siRNA in cancer cells effectively reduced the onset and growth of tumor xenografts in vivo. Therefore, 14-3-3ζ overexpression is a novel molecular marker for disease recurrence in breast cancer patients and may serve as an effective therapeutic target in patients whose tumors overexpress 14-3-3ζ. [Cancer Res 2009;69(8):3425–32]
The MET Receptor Tyrosine Kinase Is a Potential Novel Therapeutic Target for Head and Neck Squamous Cell Carcinoma
Authors: Seiwert Tanguy Y. , Jagadeeswaran Ramasamy , Faoro Leonardo , Janamanchi Varalakshmi , Nallasura Vidya , El Dinali Mohamed , Yala Soheil , Kanteti Rajani , Cohen Ezra E.W. , Lingen Mark W. , Martin Leslie , Krishnaswamy Soundararajan , Klein-Szanto Andres , Christensen James G. , Vokes Everett E. , Salgia Ravi
Published: March 2009

Recurrent/metastatic head and neck cancer remains a devastating disease with insufficient treatment options. We investigated the MET receptor tyrosine kinase as a novel target for the treatment of head and neck squamous cell carcinoma (HNSCC). MET/phosphorylated MET and HGF expression was analyzed in 121 tissues (HNSCC/normal) by immunohistochemistry, and in 20 HNSCC cell lines by immunoblotting. The effects of MET inhibition using small interfering RNA/two small-molecule inhibitors (SU11274/PF-2341066) on signaling, migration, viability, and angiogenesis were determined. The complete MET gene was sequenced in 66 head and neck cancer tissue samples and eight cell lines. MET gene copy number was determined in 14 cell lines and 23 tumor tissues. Drug combinations of SU11274 with cisplatin or erlotinib were tested in SCC35/HN5 cell lines. Eighty-four percent of the HNSCC samples showed MET overexpression, whereas 18 of 20 HNSCC cell lines (90%) expressed MET. HGF overexpression was present in 45% of HNSCC. MET inhibition with SU11274/PF-2341066 abrogated MET signaling, cell viability, motility/migration in vitro, and tumor angiogenesis in vivo. Mutational analysis of 66 tumor tissues and 8 cell lines identified novel mutations in the semaphorin (T230M/E168D/N375S), juxtamembrane (T1010I/R988C), and tyrosine kinase (T1275I/V1333I) domains (incidence: 13.5%). Increased MET gene copy number was present with >10 copies in 3 of 23 (13%) tumor tissues. A greater-than-additive inhibition of cell growth was observed when combining a MET inhibitor with cisplatin or erlotinib and synergy may be mediated via erbB3/AKT signaling. MET is functionally important in HNSCC with prominent overexpression, increased gene copy number, and mutations. MET inhibition abrogated MET functions, including proliferation, migration/motility, and angiogenesis. MET is a promising, novel target for HNSCC and combination approaches with cisplatin or EGFR inhibitors should be explored. [Cancer Res 2009;69(7):3021–31]
FMS-Like Tyrosine Kinase 3–Internal Tandem Duplication Tyrosine Kinase Inhibitors Display a Nonoverlapping Profile of Resistance Mutations In vitro
Authors: von Bubnoff Nikolas , Engh Richard A. , Åberg Espen , Sänger Jana , Peschel Christian , Duyster Justus
Published: March 2009

FMS-like tyrosine kinase 3 (FLT3) inhibitors have shown activity in the treatment of acute myelogenous leukemia (AML). Secondary mutations in target kinases can cause clinical resistance to therapeutic kinase inhibition. We have previously shown that sensitivity toward tyrosine kinase inhibitors varies between different activating FLT3 mutations. We therefore intended to determine whether different FLT3 inhibitors would produce distinct profiles of secondary, FLT3 resistance mutations. Using a cell-based screening approach, we generated FLT3–internal tandem duplication (ITD)–expressing cell lines resistant to the FLT3 inhibitors SU5614, PKC412, and sorafenib. Interestingly, the profile of resistance mutations emerging with SU5614 was limited to exchanges in the second part of the kinase domain (TK2) with exchanges of D835 predominating. In contrast, PKC412 exclusively produced mutations within tyrosine kinase domain 1 (TK1) at position N676. A mutation at N676 recently has been reported in a case of PKC412-resistant AML. TK1 mutations exhibited a differential response to SU5614, sorafenib, and sunitinib but strongly impaired response to PKC412. TK2 exchanges identified with SU5614 were sensitive to PKC412, sunitinib, or sorafenib, with the exception of Y842D, which caused a strong resistance to sorafenib. Of note, sorafenib also produced a highly distinct profile of resistance mutations with no overlap to SU5614 or PKC412, including F691L in TK1 and exchanges at position Y842 of TK2. Thus, different FLT3 kinase inhibitors generate distinct, nonoverlapping resistance profiles. This is in contrast to Bcr-Abl kinase inhibitors such as imatinib, nilotinib, and dasatinib, which display overlapping resistance profiles. Therefore, combinations of FLT3 inhibitors may be useful to prevent FLT3 resistance mutations in the setting of FLT3-ITD–positive AML. [Cancer Res 2009;69(7):3032–41]
TW-37, a Small-Molecule Inhibitor of Bcl-2, Inhibits Cell Growth and Induces Apoptosis in Pancreatic Cancer: Involvement of Notch-1 Signaling Pathway
Authors: Wang Zhiwei , Azmi Asfar Sohail , Ahmad Aamir , Banerjee Sanjeev , Wang Shaomeng , Sarkar Fazlul H. , Mohammad Ramzi M.
Published: March 2009

Overexpression of Bcl-2 family proteins has been found in a variety of aggressive human carcinomas, including pancreatic cancer, suggesting that specific agents targeting Bcl-2 family proteins would be valuable for pancreatic cancer therapy. We have previously reported that TW-37, a small-molecule inhibitor of Bcl-2 family proteins, inhibited cell growth and induced apoptosis in pancreatic cancer. However, the precise role and the molecular mechanism of action of TW-37 have not been fully elucidated. In our current study, we found that TW-37 induces cell growth inhibition and S-phase cell cycle arrest, with regulation of several important cell cycle–related genes like p27, p57, E2F-1, cdc25A, CDK4, cyclin A, cyclin D1, and cyclin E. The cell growth inhibition was accompanied by increased apoptosis with concomitant attenuation of Notch-1, Jagged-1, and its downstream genes such as Hes-1 in vitro and in vivo. We also found that down-regulation of Notch-1 by small interfering RNA or γ-secretase inhibitors before TW-37 treatment resulted in enhanced cell growth inhibition and apoptosis. Our data suggest that the observed antitumor activity of TW-37 is mediated through a novel pathway involving inactivation of Notch-1 and Jagged-1. [Cancer Res 2009;69(7):2757–65]
Noninvasive Imaging of αVβ3 Function as a Predictor of the Antimigratory and Antiproliferative Effects of Dasatinib
Authors: Dumont Rebecca A. , Hildebrandt Isabel , Su Helen , Haubner Roland , Reischl Gerald , Czernin Johannes G. , Mischel Paul S. , Weber Wolfgang A.
Published: March 2009

Src family kinases (SFKs) are commonly deregulated in cancer cells. Among other functions, SFKs are critical for cellular migration and invasion. SFK inhibitors are being studied as targeted cancer drugs, but there are no biomarkers for noninvasive assessment of SFK inhibition. The aim of this study was to evaluate whether imaging of αVβ3 integrin activity with positron emission tomography (PET) and [64Cu]DOTA-cyclo-(Arg-Gly-Asp-dPhe-Lys) {[64Cu]DOTA-c(RGDfK)} can be used for monitoring response to the SFK inhibitor dasatinib. Severe combined immunodeficient mice bearing U87MG xenografts were gavaged daily over 72 hours with 72 or 95 mg/kg of dasatinib or vehicle. Tumor uptake of [64Cu]DOTA-c(RGDfK) was measured by small-animal PET. In parallel, fluorodeoxyglucose (FDG) scans were performed to assess tumor metabolism in response to dasatinib treatment. Dasatinib significantly (P < 0.0001) reduced [64Cu]DOTA-c(RGDfK) uptake by up to 59% in U87MG xenografts [2.10 ± 0.14% injected dose/gram (ID/g) in the 95 mg/kg group and 3.12 ± 0.18% ID/g in the 72 mg/kg group, versus 5.08 ± 0.80% ID/g in controls]. In contrast, tumor FDG uptake showed no significant reduction with dasatinib therapy (8.13 ± 0.45% ID/g in treated versus 10.39 ± 1.04% ID/g in controls; P = 0.170). Histologically, tumors were viable at the time of the follow-up PET scan but showed inhibition of focal adhesion kinase. Continued dasatinib treatment resulted in a significant inhibition of tumor growth (tumor size on day 10 of therapy: 21.13 ± 2.60 mm2 in treated animals versus 122.50 ± 17.68 mm2 in controls; P = 0.001). [64Cu]DOTA-c(RGDfK) may provide a sensitive means of monitoring tumor response to SFK inhibition in αVβ3-expressing cancers early in the course of therapy. [Cancer Res 2009;69(7):3173–9]
Naringenin: A Potential Immunomodulator for Inhibiting Lung Fibrosis and Metastasis
Authors: Du Gangjun , Jin Lingtao , Han Xiaofen , Song Zihui , Zhang Hongyan , Liang Wei
Published: March 2009

Patients with idiopathic pulmonary fibrosis have a high incidence of lung cancer and a worse prognosis for clinical treatment. A few molecules with antifibrosis properties have been shown promoting cancer progression in clinical trials. The objective of this study was to determine whether there is a similar tendency in mice as in human beings and whether these mice models may be used to find new therapeutic agents with antifibrotic properties but not cancer-promoting properties. We used bleomycin to induce pulmonary fibrosis in mice with or without naringenin treatment and measured the immune-associated lymphocytes and their secreted cytokines using flow cytometry and ELISA from lung tissue. Both passive and spontaneous metastatic models in bleomycin-treated C57BL/6 and BALB/c mice were used to test the hypothesis that mice with pulmonary fibrosis could have an increased risk of lung cancer and associated cancer progression. Here, we show that mice with lung fibrosis challenged using tumors show an increased incidence of lung metastasis and shorter life spans compared with the mice without lung fibrosis. A fibrotic environment in the lung results in increased abundance of transforming growth factor-β1 and CD4+CD25+Foxp3+ regulatory T cells and a decreased proportion of activated effector T cells. This grave immunosuppressive environment favors tumor localization and growth. Naringenin significantly reduces lung metastases in mice with pulmonary fibrosis and increases their survival by improving the immunosuppressive environment through down-regulating transforming growth factor-β1 and reducing regulatory T cells. Naringenin could be an ideal therapeutic agent in the treatment of both cancer and fibrosis. [Cancer Res 2009;69(7):3205–12]
Association of Estrogen Receptor α and Histone Deacetylase 6 Causes Rapid Deacetylation of Tubulin in Breast Cancer Cells
Authors: Azuma Kotaro , Urano Tomohiko , Horie-Inoue Kuniko , Hayashi Shin-ichi , Sakai Ryuichi , Ouchi Yasuyoshi , Inoue Satoshi
Published: March 2009

Estrogen receptor α (ERα) is a nuclear receptor that functions as a ligand-activated transcription factor. Besides its genomic action in nuclei, ERα could exert nongenomic actions at the plasma membrane. To investigate the mechanism underlying the nongenomic action of ERα in breast cancer cells, we generated a construct of membrane-targeted ERα (memER), an expression vector of ERα without the nuclear localizing signal and including instead the membrane-targeting sequence of Src kinase. MemER was stably expressed in human breast cancer MCF-7 cells. Cell migration test and tumorigenic assay in nude mice revealed that the in vitro motility and the in vivo proliferation activity of MCF-7 cells expressing memER were significantly enhanced compared with those of vector-transfected cells. Interestingly, the acetylation level of tubulin in memER-overexpressing cells was lower than that in control cells. We found that histone deacetylase (HDAC) 6 translocated to the plasma membrane shortly after estrogen stimulation, and rapid tubulin deacetylation subsequently occurred. We also showed that memER associated with HDAC6 in a ligand-dependent manner. Although tamoxifen is known for its antagonistic role in the ERα genomic action in MCF-7 cells, the agent showed an agonistic function in the memER-HDAC6 association and tubulin deacetylation. These findings suggest that ERα ligand dependently forms a complex with HDAC6 and tubulin at the plasma membrane. Estrogen-dependent tubulin deacetylation could provide new evidence for the nongenomic action of estrogen, which potentially contributes to the aggressiveness of ERα-positive breast cancer cells. [Cancer Res 2009;69(7):2935–40]
Coordinates in the Universe of Node-Negative Breast Cancer Revisited
Authors: Schmidt Marcus , Hengstler Jan G. , von Törne Christian , Koelbl Heinz , Gehrmann Mathias C.
Published: March 2009

We present a global picture of the natural history of node-negative breast cancer in which two of three important biological processes have outstanding prognostic consequences. We propose that the transition from slow to fast proliferation of the tumor leads to the most dramatic aggravation of prognosis. Second, immune cell infiltration is of major importance to prevent disease progression in fast-proliferating breast carcinomas, regardless of estrogen receptor status. In the absence of endocrine treatment, steroid hormone receptor expression as a third axis is of limited prognostic importance. Dissecting tumors according to these three major biological axes will allow further understanding of biological processes relevant for tumor progression in patients with node-negative breast cancer. [Cancer Res 2009;69(7):2695–8]
Endothelial Nitric Oxide Synthase Mediates Lymphangiogenesis and Lymphatic Metastasis
Authors: Lahdenranta Johanna , Hagendoorn Jeroen , Padera Timothy P. , Hoshida Tohru , Nelson Gregory , Kashiwagi Satoshi , Jain Rakesh K. , Fukumura Dai
Published: March 2009

Lymphatic metastasis is a critical determinant of cancer prognosis. Recently, several lymphangiogenic molecules such as vascular endothelial growth factor (VEGF)-C and VEGF-D were identified. However, the mechanistic understanding of lymphatic metastasis is still in infancy. Nitric oxide (NO) plays a crucial role in regulating blood vessel growth and function as well as lymphatic vessel function. NO synthase (NOS) expression correlates with lymphatic metastasis. However, causal relationship between NOS and lymphatic metastasis has not been documented. To this end, we first show that both VEGF receptor-2 and VEGF receptor-3 stimulation activate eNOS in lymphatic endothelial cells and that NO donors induce proliferation and/or survival of cultured lymphatic endothelial cells in a dose-dependent manner. We find that an NOS inhibitor, L-NMMA, blocked regeneration of lymphatic vessels. Using intravital microscopy that allows us to visualize the steps of lymphatic metastasis, we show that genetic deletion of eNOS as well as NOS blockade attenuates peritumor lymphatic hyperplasia of VEGF-C–overexpressing T241 fibrosarcomas and decreases the delivery of metastatic tumor cells to the draining lymph nodes. Genetic deletion of eNOS in the host also leads to a decrease in T241 tumor cell dissemination to the lymph nodes and macroscopic lymph node metastasis of B16F10 melanoma. These findings indicate that eNOS mediates VEGF-C–induced lymphangiogenesis and, consequently, plays a critical role in lymphatic metastasis. Our findings explain the correlation between NOS and lymphatic metastasis seen in a number of human tumors and open the door for potential therapies exploiting NO signaling to treat diseases of the lymphatic system. [Cancer Res 2009;69(7):2801–8]
Noninvasive De novo Imaging of Human Embryonic Stem Cell–Derived Teratoma Formation
Authors: Cao Feng , Li Zibo , Lee Andrew , Liu Zhaofei , Chen Kai , Wang Hui , Cai Weibo , Chen Xiaoyuan , Wu Joseph C.
Published: March 2009

Teratoma formation can be a serious drawback after the therapeutic transplantation of human embryonic stem (hES) cells. Therefore, noninvasive imaging of teratomas could be a valuable tool for monitoring patients undergoing hES cell treatment. Here, we investigated the angiogenic process within teratomas derived from hES cells and now report the first example of using 64Cu-labeled RGD tetramer (64Cu-DOTA-RGD4) for positron emission tomography imaging of teratoma formation by targeting αvβ3 integrin. H9 hES cells (2 × 106), stably expressing firefly luciferase, and enhanced green fluorescence protein (Fluc-eGFP) were injected into adult nude mice (n = 12) s.c. Eight weeks after transplantation, these hES cell grafts evolved into teratomas as confirmed by longitudinal bioluminescence imaging. Under micropositron emission tomography imaging, 2-deoxy-2-[18F]fluoro-D-glucose and 3′-deoxy-3′-[18F]-fluorothymidine both failed to detect hES cell–derived teratomas (0.8 ± 0.5 versus 1.1 ± 0.4 %ID/g, respectively; P = not significant versus background signals). By contrast, 64Cu-DOTA-RGD4 revealed specific and prominent uptake in vascularized teratoma and significantly lower uptake in control tumors (human ovarian carcinoma 2008 cell line), which had low intergrin expression (10.1 ± 3.4 versus 1.4 ± 1.2 %ID/g; P < 0.01). Immunofluorescence staining of CD31 and β3 integrin also supported our in vivo imaging results (P < 0.05). Moreover, we found that the cells dissociated from teratomas showed higher αvβ3 integrin expression than the 2008 cells. In conclusion, by targeting αvβ3 integrin, we successfully showed the ability of 64Cu-DOTA-RGD4 to noninvasively visualize teratoma formation in vivo for the first time. [Cancer Res 2009;69(7):2709–13]
Altered Subcellular Localization of Tumor-Specific Cyclin E Isoforms Affects Cyclin-Dependent Kinase 2 Complex Formation and Proteasomal Regulation
Authors: Delk Nikki A. , Hunt Kelly K. , Keyomarsi Khandan
Published: March 2009

In tumors, alternative translation and posttranslational proteolytic cleavage of full-length cyclin E (EL) produces tumorigenic low molecular weight cyclin E (LMW-E) isoforms that lack a portion of the EL amino-terminus containing a nuclear localization sequence. Therefore, we hypothesized that LMW-E isoforms have altered subcellular localization. To explore our hypothesis, we compared EL versus LMW-E localization in cell lysates and in vivo using fractionation and protein complementation assays. Our results reveal that LMW-E isoforms preferentially accumulate in the cytoplasm where they bind the cyclin E kinase partner, cyclin-dependent kinase 2 (Cdk2), and have associated kinase activity. The nuclear ubiquitin ligase Fbw7 targets Cdk2-bound cyclin E for degradation; thus, we examined if altered subcellular localization affected LMW-E degradation. We found that cytoplasmic LMW-E/Cdk2 was less susceptible to Fbw7-mediated degradation. One implication of our findings is that altered LMW-E and LMW-E/Cdk2 subcellular localization may lead to aberrant LMW-E protein interactions, regulation, and activity, ultimately contributing to LMW-E tumorigenicity. [Cancer Res 2009;69(7):2817–25]
A Breast Cancer Risk Haplotype in the Caspase-8 Gene
Authors: Shephard Neil Duncan , Abo Ryan , Rigas Sushila Harkisandas , Frank Bernd , Lin Wei-Yu , Brock Ian Wallace , Shippen Adam , Balasubramanian Sabapathy Prakash , Reed Malcolm Walter Ronald , Bartram Claus Rainer , Meindl Alfons , Schmutzler Rita Katharina , Engel Christoph , Burwinkel Barbara , Cannon-Albright Lisa Anne , Allen-Brady Kristina , Camp Nicola Jane , Cox Angela
Published: March 2009

Recent large-scale studies have been successful in identifying common, low-penetrance variants associated with common cancers. One such variant in the caspase-8 (CASP8) gene, D302H (rs1045485), has been confirmed to be associated with breast cancer risk, although the functional effect of this polymorphism (if any) is not yet clear. In order to further map the CASP8 gene with respect to breast cancer susceptibility, we performed extensive haplotype analyses using single nucleotide polymorphisms (SNP) chosen to tag all common variations in the gene (tSNP). We used a staged study design based on 3,200 breast cancer and 3,324 control subjects from the United Kingdom, Utah, and Germany. Using a haplotype-mining algorithm in the UK cohort, we identified a four-SNP haplotype that was significantly associated with breast cancer and that was superior to any other single or multi-locus combination (P = 8.0 × 10−5), with a per allele odds ratio and 95% confidence interval of 1.30 (1.12–1.49). The result remained significant after adjustment for the multiple testing inherent in mining techniques (false discovery rate, q = 0.044). As expected, this haplotype includes the D302H locus. Multicenter analyses on a subset of the tSNPs yielded consistent results. This risk haplotype is likely to carry one or more underlying breast cancer susceptibility alleles, making it an excellent candidate for resequencing in homozygous individuals. An understanding of the mode of action of these alleles will aid risk assessment and may lead to the identification of novel treatment targets in breast cancer. [Cancer Res 2009;69(7):2724–8]