bluuebunny/crossref_metadata_2025 huggingface dataset:
Limits to the Control of the Human Thumb and Fingers in Flexion and Extension
Authors: Yu W. S. , van Duinen H. , Gandevia S. C.
Published: November 2009

In humans, hand performance has evolved from a crude multidigit grasp to skilled individuated finger movements. However, control of the fingers is not completely independent. Although musculotendinous factors can limit independent movements, constraints in supraspinal control are more important. Most previous studies examined either flexion or extension of the digits. We studied differences in voluntary force production by the five digits, in both flexion and extension tasks. Eleven healthy subjects were instructed either to maximally flex or extend their digits, in all single- and multidigit combinations. They received visual feedback of total force produced by “instructed” digits and had to ignore “noninstructed” digits. Despite attempts to maximally flex or extend instructed digits, subjects rarely generated their “maximal” force, resulting in a “force deficit,” and produced forces with noninstructed digits (“enslavement”). Subjects performed differently in flexion and extension tasks. Enslavement was greater in extension than in flexion tasks ( P = 0.019), whereas the force deficit in multidigit tasks was smaller in extension ( P = 0.035). The difference between flexion and extension in the relationships between the enslavement and force deficit suggests a difference in balance of spillover of neural drive to agonists acting on neighboring digits and focal neural drive to antagonist muscles. An increase in drive to antagonists would lead to more individualized movements. The pattern of force production matches the daily use of the digits. These results reveal a neural control system that preferentially lifts fingers together by extension but allows an individual digit to flex so that the finger pads can explore and grasp.
Processing of Targets in Smooth or Apparent Motion Along the Vertical in the Human Brain: An fMRI Study
Authors: Maffei Vincenzo , Macaluso Emiliano , Indovina Iole , Orban Guy , Lacquaniti Francesco
Published: November 2009

Neural substrates for processing constant speed visual motion have been extensively studied. Less is known about the brain activity patterns when the target speed changes continuously, for instance under the influence of gravity. Using functional MRI (fMRI), here we compared brain responses to accelerating/decelerating targets with the responses to constant speed targets. The target could move along the vertical under gravity (1 g), under reversed gravity (−1 g), or at constant speed (0 g). In the first experiment, subjects observed targets moving in smooth motion and responded to a GO signal delivered at a random time after target arrival. As expected, we found that the timing of the motor responses did not depend significantly on the specific motion law. Therefore brain activity in the contrast between different motion laws was not related to motor timing responses. Average BOLD signals were significantly greater for 1 g targets than either 0 g or −1 g targets in a distributed network including bilateral insulae, left lingual gyrus, and brain stem. Moreover, in these regions, the mean activity decreased monotonically from 1 g to 0 g and to −1 g. In the second experiment, subjects intercepted 1 g, 0 g, and −1 g targets either in smooth motion (RM) or in long-range apparent motion (LAM). We found that the sites in the right insula and left lingual gyrus, which were selectively engaged by 1 g targets in the first experiment, were also significantly more active during 1 g trials than during −1 g trials both in RM and LAM. The activity in 0 g trials was again intermediate between that in 1 g trials and that in −1 g trials. Therefore in these regions the global activity modulation with the law of vertical motion appears to hold for both RM and LAM. Instead, a region in the inferior parietal lobule showed a preference for visual gravitational motion only in LAM but not RM.
LC/MS/MS Analysis of N‐Terminal Protein Adducts with Improved Sensitivity: A Comparison of Selected Edman Isothiocyanate Reagents
Authors: Rydberg Per , von Stedingk Hans , Magnér Jörgen , Björklund Jonas
Published: November 2009

This study provides a basis for a new and straightforward method for LC/MS/MS‐based screening of N‐terminal protein adducts. This procedure is denoted the “FIRE procedure” as fluorescein isothiocyanate (FITC) gave superior sensitivity by LC/MS/MS when measuring adducts (R) of electrophilic
compounds with a modified Edman procedure. The principles of the FIRE‐procedure  are that adducts to N‐terminal amino acids selectively are detached and measured from of proteins after derivatisation by isothiocyanate Edman reagents. In this study, FITC, 4‐N,N‐dimethylaminoazobenzene 4′‐isothiocyanate
(DABITC) and 4‐dimethylamino‐1‐naphthyl isothiocyanate (DNITC) were used to synthesize
thiohydantoin analytes from valine and N‐methylvaline. The sensitivity by LC/MS/MS was enhanced
by up to three orders of magnitude as compared to phenyl isothiocyanate and higher as compared to
pentafluorophenyl isothiocyanate. The FITC reagent will enable measurements of low background
adduct levels. Synthesized analytes were characterised with, for example,  1H NMR,  13C NMR, LC/MS/MS, and UV.
Sofa-TV: The New Digital Landscape
Authors: Toletti Giovanni , Turba Luca
Published: November 2009

Television is attracting an enormous amount of attention from both researchers and managers, due to the profound changes that are taking place thanks to the diffusion of digital technology. The study of the digital landscape of television, including the players competing in its arena and their strategies, is well worth the effort. This paper, based on 32 case studies and the census of the Sofa-TV (Sat TV, DTT, and IPTV) offerings, aims at describing the current state of channel offerings, individualizing the principal players, and identifying their strategies, thus allowing us to give a few predictions as to the possible future changes in the industry. The analysis will have a general applicability, as the considerations made are not particularly country-specific, although performed within the Italian context, one of the most advanced in the development of digital television platforms.
Dynamical Analysis of DTNN with Impulsive Effect
Authors: Chen Chao , Huang Zhenkun , Bin Honghua , Liu Xiaohui
Published: November 2009

We present dynamical analysis of discrete‐time delayed neural networks with impulsive effect. Under impulsive effect, we derive some new criteria for the invariance and attractivity of discrete‐time neural networks by using decomposition approach and delay difference inequalities. Our results improve or extend the existing ones.
Folgoration as an Example of Pathergy in a Patient Affected by Pyoderma Gangrenosum and Takayasu's Arteritis
Authors: Richetta A. G. , D'Epiro S. , Mattozzi C. , Giancristoforo S. , Calvieri S.
Published: November 2009

Pyoderma gangrenosum (PG) is a neutrophilic dermatosis of unknown aetiology. Clinical manifestations of PG are characterized by destructive, necrotizing, and noninfective ulceration of the skin. 20–30% of cases are initiated and aggravated by minor trauma or surgery, a phenomenon named pathergy. PG is related to several autoimmune diseases including ulcerative colitis, Crohn's disease, rheumatoid arthritis, and monoclonal gammopathy. The association with Takayasu's arteritis (TA), a chronic inflammatory and stenotic disease of large and medium-sized arteries, is instead less common. We report a case of PG associated with TA that was induced by an accident with folgoration of the skin; in this case the folgoration can be considered as an exemple of Pathergy, that is, a characteristic feature of PG.
Dermaseptins and Magainins: Antimicrobial Peptides from Frogs′ Skin—New Sources for a Promising Spermicides Microbicides—A Mini Review
Authors: Zairi Amira , Tangy Frédéric , Bouassida Khaireddine , Hani Khaled
Published: November 2009

Sexually transmitted infections (STIs) and human immunodeficiency virus (HIV), the causative agents of acquired immunodeficiency syndrome (AIDS), are two great concerns in the reproductive health of women. Thus, the challenge is to find products with a double activity, on the one hand having antimicrobial/antiviral properties with a role in the reduction of STI, and on the other hand having spermicidal action to be used as a contraceptive. In the absence of an effective microbicide along with the disadvantages of the most commonly used spermicidal contraceptive worldwide, nonoxynol‐9, new emphasis has been focused on the development of more potential intravaginal microbicidal agents. Topical microbicides spermicides would ideally provide a female‐controlled method of self‐protection against HIV as well as preventing pregnancies. Nonoxynol‐9, the only recommended microbicide spermicide, damages cervicovaginal epithelium because of its membrane‐disruptive properties. Clearly, there is an urgent need to identify new compounds with dual potential microbicidal properties; antimicrobial peptides should be candidates for such investigations. Dermaseptins and magainins are two classes of cationic, amphipathic α‐helical peptides that have been identified in the skin extracts of frogs Phyllomedusa sauvagei and Xenopus laevis. Regarding their contraceptive activities and their effect against various STI‐causing pathogens, we believe that these two peptides are appropriate candidates in the evaluation of newer and safer microbicides spermicides in the future.
Prognostic Value of Microvascular Density in Dukes A and B (T1–T4, N0, M0) Colorectal Carcinomas
Authors: Uribarrena A Rafael , Ortego Javier , Fuentes Javier , Raventós Nuria , Parra Pilar , Uribarrena E Rafael
Published: November 2009

Background. Aproximatelly 30% of patients operated on for colorectal cancer (CRC), with an expectedly favourable prognosis (Dukes A-B/T1–T4, N0, M0) suffer recurrence and/or die.Method. In order to determine if tumor microvascular density (MVD) is a prognostic factor in CRC, samples from tumors of 104 Dukes A-B CRC patients were retrospectively studied. Immunohistochemistry was performed for anti-CD34 antibody to visualize tumor vascularisation. MVD was expressed as the total number of vessels and as the percentage of microvascular area. We calculated MVD with a morphometry program and performed descriptive, bivariate, and survival statistics.Results. The mean number of vessels was 37.37/200x field, and the mean vascular area was the 3.972%. 30% of the patients with<37 vessels/field, and 21% of the patients with>37 vessels/field, experienced recurrence/death. The 35% of patients with<4% of vascular area died following recurrence, compared with 14% of patients with ≥4% of vascular area. These differences in % of vascular area were statistically significant.Conclusion. MVD expressed as the total number of vessels had no a statistically significant influence on the evolution of CRC. However, neoplasias with a greater % of vascular were associated to a better outcome.
On Complementary Root Locus of Biproper Transfer Functions
Authors: Teixeira Marcelo C. M. , Assunção Edvaldo , Cardim Rodrigo , Silva Neusa A. P. , Machado Erica R. M. D.
Published: November 2009

This paper addresses the root locus (locus of positive gain) and the
complementary root locus (locus of negative gain) of biproper transfer functions (transfer functions with the same number of poles and zeros). It is shown that the root locus and complementary root locus of a biproper transfer function
can be directly obtained from the plot of a suitable strictly proper transfer function (transfer function with more poles than zeros). There exists a lack of sources on the complementary root locus plots. The proposed procedure avoids the problems pointed out by Eydgahi and Ghavamzadeh, is a new method to plot complementary root locus of biproper transfer functions,
and offers a better comprehension on this subject. It also extends to biproper open‐loop transfer functions, previous results about the exact plot of the complementary root locus using only the well‐known root locus rules.
A Continuation Method for Weakly Contractive Mappings under the Interior Condition
Authors: Ariza-Ruiz David , Jiménez-Melado Antonio
Published: November 2009

Recently, Frigon proved that, for weakly contractive maps, the property of having a fixed point is invariant by a certain class of homotopies, obtaining as a consequence a Leray-Schauder alternative for this class of maps in a Banach space. We prove here that the Leray-Schauder condition in the aforementioned result can be replaced by a modification of it, the interior condition. We also show that our arguments work for a certain class of generalized contractions, thus complementing a result of Agarwal and O'Regan.
Photocatalytic Activity in CH3CN Related to the Surface Properties of TiO2 Powders Prepared by Sol‐Gel Method
Authors: Bettoni Marta , Candori Pietro , Marmottini Fabio , Perenze Nicoletta , Rol Cesare , Sebastiani Giovanni V. , Vecchiocattivi Franco
Published: November 2009

Some TiO2 powders, prepared from titanium(IV)tetraisopropoxide by the sol‐gel method and thermally treated between 100 and 1000∘C, have been characterized by X‐ray powder diffraction and by nitrogen adsorption and desorption at 77 K to calculate the BET‐specific surface area, from which the micropore volume and the external surface area can be derived. The photocatalytic activity (ka) of the above powders has been evaluated considering the TiO2‐sensitized photo‐oxidation of 4‐methoxybenzyl alcohol in CH3CN as the test reaction. The decrease of ka have been related to the decrease of the BET surface area, the micropore volume, and the external surface area of the TiO2 powders, but a satisfactory linear correlation is observed only for the last superficial parameter.
The Effects of Interleukin-1βin Tumor Necrosis Factor-α-Induced Acute Pulmonary Inflammation in Mice
Authors: Saperstein Sara , Huyck Heidie , Kimball Elizabeth , Johnston Carl , Finkelstein Jacob , Pryhuber Gloria
Published: November 2009

We determined the role of interleukin-1β(IL-1β) signaling on tumor necrosis factor alpha-induced (TNF-α) lung neutrophil influx as well as neutrophil chemoattractant macrophage inflammatory protein (MIP-2) and KC and soluble TNF-αreceptor (TNFR) levels utilizing wildtype (WT), TNF receptor double knockout (TNFR1/TNFR2 KO), and IL-1βKO mice after oropharyngeal instillation with TNF-α. A significant increase in neutrophil accumulation in bronchoalveolar lavage fluid (BALF) and lung interstitium was detected in the WT mice six hours after TNF-αexposure. This correlated with an increase in BALF MIP-2. In contrast, BALF neutrophil numbers were not increased by TNF-αtreatment of IL-1βKOs, correlating with a failure to induce BALF MIP-2 and a trend toward increased BALF soluble TNFR1. TNF-α-instillation increased lavage and serum KC and soluble TNFR2 irrespective of IL-1βexpression. These results suggest IL-1βcontributes, in part, to TNF-α-mediated, chemokine release, and neutrophil recruitment to the lung, potentially associated with altered soluble TNFR1 release into the BALF.
Repression of NHE1 Expression by PPARγ Activation Is a Potential New Approach for Specific Inhibition of the Growth of Tumor CellsIn vitroandIn vivo
Authors: Kumar Alan Prem , Quake Ai Li , Chang Michelle Ker Xing , Zhou Ting , Lim Kelly Swee Ying , Singh Rajeev , Hewitt Robert Edwin , Salto-Tellez Manuel , Pervaiz Shazib , Clément Marie-Véronique
Published: November 2009

Ligand-induced activation of peroxisome proliferator-activated receptor γ (PPARγ) inhibits proliferation in cancer cells in vitro and in vivo; however, the downstream targets remain undefined. We report the identification of a peroxisome proliferator response element in the promoter region of the Na+/H+ transporter gene NHE1, the overexpression of which has been associated with carcinogenesis. Exposure of breast cancer cells expressing high levels of PPARγ to its natural and synthetic agonists resulted in downregulation of NHE1 transcription as well as protein expression. Furthermore, the inhibitory effect of activated PPARγ on tumor colony-forming ability was abrogated on overexpression of NHE1, whereas small interfering RNA–mediated gene silencing of NHE1 significantly increased the sensitivity of cancer cells to growth-inhibitory stimuli. Finally, histopathologic analysis of breast cancer biopsies obtained from patients with type II diabetes treated with the synthetic agonist rosiglitazone showed significant repression of NHE1 in the tumor tissue. These data provide evidence for tumor-selective downregulation of NHE1 by activated PPARγ in vitro and in pathologic specimens from breast cancer patients and could have potential implications for the judicious use of low doses of PPARγ ligands in combination chemotherapy regimens for an effective therapeutic response. [Cancer Res 2009;69(22):8636–44]
Epigenetic Silencing of Interferon-κ in Human Papillomavirus Type 16–Positive Cells
Authors: Rincon-Orozco Bladimiro , Halec Gordana , Rosenberger Simone , Muschik Dorothea , Nindl Ingo , Bachmann Anastasia , Ritter Tina Maria , Dondog Bolormaa , Ly Regina , Bosch Franz X. , Zawatzky Rainer , Rösl Frank
Published: November 2009

We have investigated interferon-κ (IFN-κ) regulation in the context of human papillomavirus (HPV)–induced carcinogenesis using primary human foreskin keratinocytes (HFK), immortalized HFKs encoding individual oncoproteins of HPV16 (E6, E7, and E6/E7), and cervical carcinoma cells. Here, IFN-κ was suppressed in the presence of E6, whereas its expression was not affected in HFKs or E7-immortalized HFKs. Transcription could be reactivated after DNA demethylation but was decreased again upon drug removal. Partial reactivation could also be accomplished when E6 was knocked down, suggesting a contribution of E6 in IFN-κ de novo methylation. We identified a single CpG island near the transcriptional start site as being involved in selective IFN-κ expression. To prove the functional relevance of IFN-κ in building up an antiviral response, IFN-κ was ectopically expressed in cervical carcinoma cells where protection against vesicular stomatitis virus–mediated cytolysis could be achieved. Reconstitution of IFN-κ was accompanied by an increase of p53, MxA, and IFN-regulatory factors, which was reversed by knocking down either IFN-κ or p53 by small interfering RNA. This suggests the existence of a positive feedback loop between IFN-κ, p53, and components of IFN signaling pathway to maintain an antiviral state. Our in vitro findings were further corroborated in biopsy samples of cervical cancer patients, in which IFN-κ was also downregulated when compared with normal donor tissue. This is the first report showing an epigenetic silencing of type I IFN after HPV16 oncogene expression and revealing a novel strategy on how high-risk HPVs can abolish the innate immune response in their genuine host cells. [Cancer Res 2009;69(22):8718–25]
Wnt Signaling Stimulates Transcriptional Outcome of the Hedgehog Pathway by Stabilizing GLI1 mRNA
Authors: Noubissi Felicite K. , Goswami Srikanta , Sanek Nicholas A. , Kawakami Kazuyuki , Minamoto Toshinari , Moser Amy , Grinblat Yevgenya , Spiegelman Vladimir S.
Published: November 2009

Wnt and Hedgehog signaling pathways play central roles in embryogenesis, stem cell maintenance, and tumorigenesis. However, the mechanisms by which these two pathways interact are not well understood. Here, we identified a novel mechanism by which Wnt signaling pathway stimulates the transcriptional output of Hedgehog signaling. Wnt/β-catenin signaling induces expression of an RNA-binding protein, CRD-BP, which in turn binds and stabilizes GLI1 mRNA, causing an elevation of GLI1 expression and transcriptional activity. The newly described mode of regulation of GLI1 seems to be important to several functions of Wnt, including survival and proliferation of colorectal cancer cells. [Cancer Res 2009;69(22):8572–8]
β1-Integrin Circumvents the Antiproliferative Effects of Trastuzumab in Human Epidermal Growth Factor Receptor-2–Positive Breast Cancer
Authors: Lesniak David , Xu Yaoxian , Deschenes Jean , Lai Raymond , Thoms John , Murray David , Gosh Sunita , Mackey John R. , Sabri Siham , Abdulkarim Bassam
Published: November 2009

Resistance to trastuzumab, the monoclonal antibody targeting human epidermal growth factor receptor 2 (HER-2), is a major concern for HER-2–positive metastatic breast cancer (MBC) patients. To date, HER-2 status is the only available biomarker for selecting patients for trastuzumab-based therapy. β1-Integrin, an adhesion molecule involved in cell survival and drug resistance, shares common downstream signaling elements with HER-2, such as the phosphatidylinositol 3-kinase/Akt and extracellular signal-regulated kinase-1/2 (ERK1/2) pathways. The significance of β1-integrin expression in HER-2–positive breast cancer and its involvement in a patient's response to trastuzumab-based therapy are unknown. We show here that overexpression of β1-integrin is an independent negative prognostic factor for tumor progression of HER-2–positive MBC patients treated with trastuzumab-based chemotherapy. Enforced overexpression of β1-integrin, its small interfering RNA–induced knockdown or treatment with a β1-integrin–blocking antibody in HER-2–positive breast cancer cells, identified a strong inverse relationship between expression level of β1-integrin and in vitro sensitivity to trastuzumab. Notably, β1-integrin overexpression increased the phosphorylation of Akt-Ser473 and ERK1/2, thereby promoting survival and mitogenic signals to bypass the antiproliferative effects of trastuzumab. Our findings show that β1-integrin provides a novel independent prognostic biomarker of trastuzumab response in HER-2–positive MBC patients and suggest a new target to augment the antiproliferative effects of trastuzumab. [Cancer Res 2009;69(22):8620–8]
Inhibition of Lipocalin 2 Impairs Breast Tumorigenesis and Metastasis
Authors: Leng Xiaohong , Ding Tian , Lin Hui , Wang Yan , Hu Limei , Hu Jianhua , Feig Barry , Zhang Wei , Pusztai Lajos , Symmans W. Fraser , Wu Yun , Arlinghaus Ralph B.
Published: November 2009

Lipocalin 2 (LCN2; also known as NGAL) is a secreted glycoprotein and its elevated expression has been observed in breast cancers. However, the importance of LCN2 in breast tumorigenesis is unclear. Here, we employed a spontaneous mammary tumor mouse model showing that MMTV-ErbB2(V664E) mice lacking mouse LCN2 had significantly delayed mammary tumor formation and metastasis with reduced matrix metalloproteinase-9 activity in the blood. LCN2 expression is upregulated by HER2/phosphoinositide 3-kinase/AKT/NF-κB pathway. Decreasing LCN2 expression significantly reduced the invasion and migration ability of HER2+ breast cancer cells. Furthermore, injecting an anti-mouse LCN2 antibody into mice bearing established murine breast tumors resulted in significant blockage of lung metastasis. Our findings indicate that LCN2 is a critical factor in enhancing breast tumor formation and progression possibly in part by stabilizing matrix metalloproteinase-9. Our results suggest that inhibition of LCN2 function by an inhibitory monoclonal antibody has potential for breast cancer therapy, particularly by interfering with metastasis in aggressive types of breast cancer. [Cancer Res 2009;69(22):8579–84]
Paradoxical Dependencies of Tumor Dormancy and Progression on Basic Cell Kinetics
Authors: Enderling Heiko , Anderson Alexander R.A. , Chaplain Mark A.J. , Beheshti Afshin , Hlatky Lynn , Hahnfeldt Philip
Published: November 2009

Even after a tumor is established, it can early on enter a state of dormancy marked by balanced cell proliferation and cell death. Disturbances to this equilibrium may affect cancer risk, as they may cause the eventual lifetime clinical presentation of a tumor that might otherwise have remained asymptomatic. Previously, we showed that cell death, proliferation, and migration can play a role in shifting this dynamic, making the understanding of their combined influence on tumor development essential. We developed an individual cell-based computer model of the interaction of cancer stem cells and their nonstem progeny to study early tumor dynamics. Simulations of tumor growth show that three basic components of tumor growth—cell proliferation, migration, and death—combine in unexpected ways to control tumor progression and, thus, clinical cancer risk. We show that increased proliferation capacity in nonstem tumor cells and limited cell migration overall lead to space constraints that inhibit proliferation and tumor growth. By contrast, increasing the rate of cell death produces the expected tumor size reduction in the short term, but results ultimately in paradoxical accelerated long-term growth owing to the liberation of cancer stem cells and formation of self-metastases.[Cancer Res 2009;69(22):8814–21]
Motor Protein–Dependent Membrane Trafficking of KCl Cotransporter-4 Is Important for Cancer Cell Invasion
Authors: Chen Yih-Fung , Chou Cheng-Yang , Wilkins Robert J. , Ellory J. Clive , Mount David B. , Shen Meng-Ru
Published: November 2009

The KCl cotransporter (KCC) is a major determinant of osmotic homeostasis and plays an emerging role in tumor biology. This study stresses the important role of KCC4 in tumor malignant behavior. Real-time reverse transcription-PCR on samples collected by laser microdissection and immunofluorescent stainings with different KCC isoform antibodies indicate that KCC4 is abundant in metastatic cervical and ovarian cancer tissues. Insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) stimulate KCC4 recruitment from a presumably inactive cytoplasmic pool of endoplasmic reticulum and Golgi to plasma membrane along actin cytoskeleton that is significantly inhibited by LY294002 and wortmannin. Throughout the trafficking process, KCC4 is incorporated into lipid rafts that function as a platform for the association between KCC4 and myosin Va, an actin-dependent motor protein. KCC4 and ezrin, a membrane cytoskeleton linker, colocalize at lamellipodia of migratory cancer cells. Interference with KCC activity by either an inhibitor or a dominant-negative loss-of-function mutant profoundly suppressed the IGF-I–induced membrane trafficking of KCC4 and the structural interaction between KCC4 and ezrin near the cell surface. Endogenous cancer cell invasiveness was significantly attenuated by small interfering RNA targeting KCC4, and the residual invasiveness was much less sensitive to IGF-I or EGF stimulation. In the metastatic cancer tissues, KCC4 colocalizes with IGF-I or EGF, indicating a likely in vivo stimulation of KCC4 function by growth factors. Thus, blockade of KCC4 trafficking and surface expression may provide a potential target for the prevention of IGF-I– or EGF-dependent cancer spread. [Cancer Res 2009;69(22):8585–93]
Titanium Dioxide Nanoparticles Induce DNA Damage and Genetic Instability In vivo in Mice
Authors: Trouiller Benedicte , Reliene Ramune , Westbrook Aya , Solaimani Parrisa , Schiestl Robert H.
Published: November 2009

Titanium dioxide (TiO2) nanoparticles are manufactured worldwide in large quantities for use in a wide range of applications including pigment and cosmetic manufacturing. Although TiO2 is chemically inert, TiO2 nanoparticles can cause negative health effects, such as respiratory tract cancer in rats. However, the mechanisms involved in TiO2-induced genotoxicity and carcinogenicity have not been clearly defined and are poorly studied in vivo. The present study investigates TiO2 nanoparticles–induced genotoxicity, oxidative DNA damage, and inflammation in a mice model. We treated wild-type mice with TiO2 nanoparticles in drinking water and determined the extent of DNA damage using the comet assay, the micronuclei assay, and the γ-H2AX immunostaining assay and by measuring 8-hydroxy-2′-deoxyguanosine levels and, as a genetic instability endpoint, DNA deletions. We also determined mRNA levels of inflammatory cytokines in the peripheral blood. Our results show that TiO2 nanoparticles induced 8-hydroxy-2′-deoxyguanosine, γ-H2AX foci, micronuclei, and DNA deletions. The formation of γ-H2AX foci, indicative of DNA double-strand breaks, was the most sensitive parameter. Inflammation was also present as characterized by a moderate inflammatory response. Together, these results describe the first comprehensive study of TiO2 nanoparticles–induced genotoxicity in vivo in mice possibly caused by a secondary genotoxic mechanism associated with inflammation and/or oxidative stress. Given the growing use of TiO2 nanoparticles, these findings raise concern about potential health hazards associated with TiO2 nanoparticles exposure. [Cancer Res 2009;69(22):8784–9]
NPM-ALK Oncogenic Tyrosine Kinase Controls T-Cell Identity by Transcriptional Regulation and Epigenetic Silencing in Lymphoma Cells
Authors: Ambrogio Chiara , Martinengo Cinzia , Voena Claudia , Tondat Fabrizio , Riera Ludovica , di Celle Paola Francia , Inghirami Giorgio , Chiarle Roberto
Published: November 2009

Transformed cells in lymphomas usually maintain the phenotype of the postulated normal lymphocyte from which they arise. By contrast, anaplastic large cell lymphoma (ALCL) is a T-cell lymphoma with aberrant phenotype because of the defective expression of the T-cell receptor and other T-cell–specific molecules for still undetermined mechanisms. The majority of ALCL carries the translocation t(2;5) that encodes for the oncogenic tyrosine kinase NPM-ALK, fundamental for survival, proliferation, and migration of transformed T cells. Here, we show that loss of T-cell–specific molecules in ALCL cases is broader than reported previously and involves most T-cell receptor–related signaling molecules, including CD3ϵ, ZAP70, LAT, and SLP76. We further show that NPM-ALK, but not the kinase-dead NPM-ALKK210R, downregulated the expression of these molecules by a STAT3-mediated gene transcription regulation and/or epigenetic silencing because this downregulation was reverted by treating ALCL cells with 5-aza-2-deoxycytidine or by knocking down STAT3 through short hairpin RNA. Finally, NPM-ALK increased the methylation of ZAP70 intron 1-exon 2 boundary region, and both NPM-ALK and STAT3 regulated the expression levels of DNA methyltransferase 1 in transformed T cells. Thus, our data reveal that oncogene-deregulated tyrosine kinase activity controls the expression of molecules that determine T-cell identity and signaling. [Cancer Res 2009;69(22):8611–9]
Microarray-Based Determination of Estrogen Receptor, Progesterone Receptor, and HER2 Receptor Status in Breast Cancer
Authors: Roepman Paul , Horlings Hugo M. , Krijgsman Oscar , Kok Marleen , Bueno-de-Mesquita Jolien M. , Bender Richard , Linn Sabine C. , Glas Annuska M. , van de Vijver Marc J.
Published: November 2009

Purpose: The level of estrogen receptor (ER), progesterone receptor (PR), and HER2 aids in the determination of prognosis and treatment of breast cancer. Immunohistochemistry is currently the predominant method for assessment, but differences in methods and interpretation can substantially affect the accuracy, resulting in misclassification. Here, we investigated the association of microarray-based mRNA expression levels compared with immunohistochemistry.

Experimental Design: Microarray mRNA quantification of ER, PR, and HER2 was done by the developed TargetPrint test and compared with immunohistochemical assessment for breast tumors from 636 patients. Immunohistochemistry was done in a central laboratory and in an independent reference laboratory according to American Society of Clinical Oncology/College of American Pathologists guidelines for 100 cases. For HER2 immunohistochemistry 2+ cases, additional chromogenic in situ hybridization (CISH) was used to determine the final status.

Results: ER concordance between microarray and central immunohistochemistry was 93 [95 confidence interval (95 CI), 91-95]. Only 4 of immunohistochemistry-positive samples were classified negative using microarray, whereas 18 of immunohistochemistry-negative samples showed a positive microarray ER status. Concordance for PR was 83 (95 CI, 80-86) and 96 of all samples showed an identical classification of HER2 status by microarray and immunohistochemistry/CISH (95 CI, 94-98). Nine percent of immunohistochemistry HER2-positive samples showed a negative microarray classification. Detailed review of 11 cases with discordant classifications by American Society of Clinical Oncology/College of American Pathologists and central immunohistochemistry indicated that microarray assessment was likely to add additional information in 5 cases.

Conclusion: Microarray-based readout of ER, PR, and HER2 shows a high concordance with immunohistochemistry/CISH and provides an additional, objective, and quantitative assessment of tumor receptor status in breast cancer. (Clin Cancer Res 2009;15(22):700311)
Activation of Host Wound Responses in Breast Cancer Microenvironment
Authors: Troester Melissa A. , Lee Myung Hee , Carter Matthew , Fan Cheng , Cowan David W. , Perez Erick Roman , Pirone Jason R. , Perou Charles M. , Jerry D. Joseph , Schneider Sallie Smith
Published: November 2009

Purpose: Cancer progression is mediated by processes that are also important in wound repair. As a result, cancers have been conceptualized as overhealing wounds or wounds that do not heal, and gene expression signatures reflective of wound repair have shown value as predictors of breast cancer survival. Despite the widespread acknowledgment of commonalities between host responses to wounds and host responses to cancer, the gene expression responses of normal tissue adjacent to cancers have not been well characterized.

Experimental Design: Using RNA extracted from histologically normal breast tissue from 107 patients, including 60 reduction mammoplasty patients and 47 cancer patients, we measured whole genome expression profiles and identified a gene expression signature that is induced in response to breast cancer.

Results: This signature represents an in vivo wound response signature that is differentially expressed in the normal tissue of breast cancer patients compared with those without disease and is highly accurate (at least 92 sensitivity and 98 specificity) in distinguishing diseased and nondiseased. The in vivo wound response signature is highly prognostic of breast cancer survival, and there is a strong association between the groups identified by this signature and those identified using serum-treated fibroblasts and other microenvironment-derived or microenvironment-related signatures.

Conclusions: The prevalence of the wound response signature in histologically normal tissue adjacent to breast cancer suggests that microenvironment response is an important variable in breast cancer progression and may be an important target for clinical interventions. (Clin Cancer Res 2009;15(22):70208)
Lysine 63 Polyubiquitination in Immunotherapy and in Cancer-promoting Inflammation
Authors: Martinez-Forero Ivan , Rouzaut Ana , Palazon Asis , Dubrot Juan , Melero Ignacio
Published: November 2009

Covalent and reversible post-translational modifications of proteins are a common theme in signaling. Ubiquitin conjugation was originally described to target proteins to proteasomal degradation by ubiquitin polymerization involving lysine (K) 48 residues. Differently linked polymers of polyubiquitin have been found that modify proteins without targeting to proteasomal degradation. Instead this pathway creates docking sites for signaling scaffolds that are key to control the nuclear factor-B (NF-B) pathway. Indeed TRAF-2, TRAF-6, and TRAF-3 are E3 ubiquitin ligases that form K63-linked ubiquitin polymers. Therefore signaling via TNF family receptors, IL1R, IL-18R, T-cell receptor (TCR), and Toll-like receptors (TLR) use this type of post-translational modification. Specific enzymes exist (DUBs) that deactivate this system, degrading K63 polyubiquitin chains. Interestingly, mice deficient in these deubiquitinases develop autoimmunity and inflammation. In carcinogenesis, the K63 polyubiquitin pathway is possibly critical for inflammation-driven tumor promotion. The pathway is also critically involved in costimulation of tumor immunity/immunotherapy as well as in the biology of malignant cells themselves. The elements of this new signaling paradigm offer the opportunity for therapeutic exploitation and drug discovery. (Clin Cancer Res 2009;15(22):67517)
Combined Inhibition of Janus Kinase 1/2 for the Treatment of JAK2V617F-Driven Neoplasms: Selective Effects on Mutant Cells and Improvements in Measures of Disease Severity
Authors: Liu Phillip C.C. , Caulder Eian , Li Jun , Waeltz Paul , Margulis Alex , Wynn Richard , Becker-Pasha Mary , Li Yanlong , Crowgey Erin , Hollis Gregory , Haley Patrick , Sparks Richard B. , Combs Andrew P. , Rodgers James D. , Burn Timothy C. , Vaddi Kris , Fridman Jordan S.
Published: November 2009

Purpose: Deregulation of the Janus kinase-signal transducers and activators of transcription (JAK-STAT) pathway is a hallmark for the Philadelphia chromosomenegative myeloproliferative diseases polycythemia vera, essential thrombocythemia, and primary myelofibrosis. We tested the efficacy of a selective JAK1/2 inhibitor in cellular and in vivo models of JAK2-driven malignancy.

Experimental Design: A novel inhibitor of JAK1/2 was characterized using kinase assays. Cellular effects of this compound were measured in cell lines bearing the JAK2V617F or JAK1V658F mutation, and its antiproliferative activity against primary polycythemiavera patient cells was determined using clonogenic assays. Antineoplastic activity in vivo was determined using a JAK2V617F-driven xenograft model, and effects of the compound on survival, organomegaly, body weight, and disease-associated inflammatory markers were measured.

Results: INCB16562 potently inhibited proliferation of cell lines and primary cells from PV patients carrying the JAK2V617F or JAK1V658F mutation by blocking JAK-STAT signaling and inducing apoptosis. In vivo, INCB16562 reduced malignant cell burden, reversed splenomegaly and normalized splenic architecture, improved body weight gains, and extended survival in a model of JAK2V617F-driven hematologic malignancy. Moreover, these mice suffered from markedly elevated levels of inflammatory cytokines, similar to advanced myeloproliferative disease patients, which was reversed upon treatment.

Conclusions: These data showed that administration of the dual JAK1/2 inhibitor INCB16562 reduces malignant cell burden, normalizes spleen size and architecture, suppresses inflammatory cytokines, improves weight gain, and extends survival in a rodent model of JAK2V617F-driven hematologic malignancy. Thus, selective inhibitors of JAK1 and JAK2 represent a novel therapy for the patients with myeloproliferative diseases and other neoplasms associated with JAK dysregulation. (Clin Cancer Res 2009;15(22):6891900)
Sarcopenia in an Overweight or Obese Patient Is an Adverse Prognostic Factor in Pancreatic Cancer
Authors: Tan Benjamin H.L. , Birdsell Laura A. , Martin Lisa , Baracos Vickie E. , Fearon Kenneth C.H.
Published: November 2009

Purpose: The average weight-losing pancreatic cancer patient undergoing palliative therapy is frequently overweight rather than underweight, and this can confound conventional measures used for risk stratification. The aim of this study was to evaluate if weight and body composition, specifically sarcopenia, assessed from diagnostic computed tomography (CT) scans, is of prognostic value in patients with pancreatic cancer. The nature and extent of tissue loss over subsequent months was also evaluated.

Experimental Design: A total of 111 patients entering a palliative therapy program, who had CT images and had undergone nutritional screening, were studied. In patients for whom follow-up scans were available (n = 44), longitudinal changes in body composition were studied at a mean of 230 62 and 95 60 days prior to demise.

Results: Sixty-two patients (55.9) were sarcopenic, 44 (39.6) were overweight/obese, and 18 (16.2) were both. Age 59 years (hazard ratio, 1.71; 95 confidence interval, 1.10-2.66; P = 0.018), and overweight/obese sarcopenia (hazard ratio, 2.07; 95 confidence interval, 1.23-3.50; P = 0.006) were identified as independent predictors of survival on multivariate analysis. Longitudinal analysis revealed that total fat-free mass index decreased from 15.5 2.5 kg/m2 to 14.5 2.0 kg/m2 (P = 0.002), and total fat mass index decreased from 7.5 2.0kg/m2 to 6.0 1.5kg/m2 (P < 0.0001) over 135 days.

Conclusions: Sarcopenia in overweight/obese patients with advanced pancreatic cancer is an occult condition but can be identified using CT scans. This condition is an independent adverse prognostic indicator that should be considered for stratification of patients' entering clinical trials, systemic therapy, or support care programs. (Clin Cancer Res 2009;15(22):69739)
Snail Promotes CXCR2 LigandDependent Tumor Progression in NonSmall Cell Lung Carcinoma
Authors: Yanagawa Jane , Walser Tonya C. , Zhu Li X. , Hong Longsheng , Fishbein Michael C. , Mah Vei , Chia David , Goodglick Lee , Elashoff David A. , Luo Jie , Magyar Clara E. , Dohadwala Mariam , Lee Jay M. , St. John Maie A. , Strieter Robert M. , Sharma Sherven , Dubinett Steven M.
Published: November 2009

Purpose: As a transcriptional repressor of E-cadherin, Snail has predominantly been associated with epithelial-mesenchymal transition, invasion, and metastasis. However, other important Snail-dependent malignant phenotypes have not been fully explored. Here, we investigate the contributions of Snail to the progression of nonsmall cell lung cancer (NSCLC).

Experimental Design: Immunohistochemistry was done to quantify and localize Snail in human lung cancer tissues, and tissue microarray analysis was used to correlate these findings with survival. NSCLC cell lines gene-modified to stably overexpress Snail were evaluated in vivo in two severe combined immunodeficiency murine tumor models. Differential gene expression between Snail-overexpressing and control cell lines was evaluated using gene expression microarray analysis.

Results: Snail is upregulated in human NSCLC tissue, and high levels of Snail expression correlate with decreased survival (P < 0.026). In a heterotopic model, mice bearing Snail-overexpressing tumors developed increased primary tumor burden (P = 0.008). In an orthotopic model, mice bearing Snail-overexpressing tumors also showed a trend toward increased metastases. In addition, Snail overexpression led to increased angiogenesis in primary tumors as measured by MECA-32 (P < 0.05) positivity and CXCL8 (P = 0.002) and CXCL5 (P = 0.0003) concentrations in tumor homogenates. Demonstrating the importance of these proangiogenic chemokines, the Snail-mediated increase in tumor burden was abrogated with CXCR2 blockade. Gene expression analysis also revealed Snail-associated differential gene expression with the potential to affect angiogenesis and diverse aspects of lung cancer progression.

Conclusion: Snail upregulation plays a role in human NSCLC by promoting tumor progression mediated by CXCR2 ligands. (Clin Cancer Res 2009;15(22):68209)
Gene Expression Profiling of Paraffin-Embedded Primary Melanoma Using the DASL Assay Identifies Increased Osteopontin Expression as Predictive of Reduced Relapse-Free Survival
Authors: Conway Caroline , Mitra Angana , Jewell Rosalyn , Randerson-Moor Juliette , Lobo Samira , Nsengimana Jrmie , Edward Sara , Sanders D. Scott , Cook Martin , Powell Barry , Boon Andy , Elliott Faye , de Kort Floor , Knowles Margaret A. , Bishop D. Timothy , Newton-Bishop Julia
Published: November 2009

Purpose: Gene expression studies in melanoma have been few because tumors are small and cryopreservation is rarely possible. The purpose of this study was to evaluate the Illumina DASL Array Human Cancer Panel for gene expression studies in formalin-fixed melanoma primary tumors and to identify prognostic biomarkers.

Experimental Design: Primary tumors from two studies were sampled using a tissue microarray needle. Study 1: 254 tumors from a melanoma cohort recruited from 2000 to 2006. Study 2: 218 tumors from a case-control study of patients undergoing sentinel node biopsy.

Results: RNA was obtained from 76 of blocks; 1.4 of samples failed analysis (transcripts from <250 of the 502 genes on the DASL chip detected). Increasing age of the block and increased melanin in the tumor were associated with reduced number of genes detected. The gene whose expression was most differentially expressed in association with relapse-free survival in study 1 was osteopontin (SPP1; P = 2.11 106) and supportive evidence for this was obtained in study 2 used as a validation set (P = 0.006; unadjusted data). Osteopontin level in study 1 remained a significant predictor of relapse-free survival when data were adjusted for age, sex, tumor site, and histologic predictors of relapse. Genes whose expression correlated most strongly with osteopontin were PBX1, BIRC5 (survivin), and HLF.

Conclusion: Expression data were obtained from 74 of primary melanomas and provided confirmatory evidence that osteopontin expression is a prognostic biomarker. These results suggest that predictive biomarker studies may be possible using stored blocks from mature clinical trials. (Clin Cancer Res 2009;15(22):693946)
Identification of LIV1, a Putative Zinc Transporter Gene Responsible for HDACi-Induced Apoptosis, Using a Functional Gene Screen Approach
Authors: Ma Xiaoli , Ma Quanfu , Liu Jia , Tian Yuan , Wang Beibei , Taylor Kathryn M. , Wu Peng , Wang Daowen , Xu Gang , Meng Li , Wang Shixuan , Ma Ding , Zhou Jianfeng
Published: November 2009

Histone deacetylase inhibitors (HDACi) show promise as a novel class of antitumoral agents and have shown the ability to induce apoptosis of tumor cells. To gain a better understanding of the action of HDACi, we conducted a functional gene screen approach named suppression of mortality by antisense rescue technique to identify the key genes responsible for the tumor-selective killing trichostatin A. Over 20 genes associated with HDACi-induced mortality were identified. One of the confirmed positive hits is LIV1, a putative zinc transporter. LIV1 is significantly induced by treatment with HDACi in a number of tumor cells, but not in normal cells. Knockdown of LIV1 suppressed apoptosis induced by HDACi in tumor cells. Although HDACi induced a slight increase in the free intracellular zinc concentration, knockdown of LIV1 significantly enhanced the intracellular zinc level, which was associated with resistance to apoptosis. On the other hand, pretreatment of the cells with a specific zinc chelator TPEN reversed the apoptosis resistance conferred by knockdown of LIV1. However, the biological effects of TPEN were abolished by addition of physiologic concentrations of zinc. Taken together, the present study identifies LIV1 as a critical mediator responsible for HDACi-induced apoptosis. The effect of LIV1 is, at least in part, mediated by affecting intracellular zinc homeostasis, which may be related to alteration of the catalytic activity of the Caspase 3 and expression of some BCL-2 family genes. As such, these findings highlight a novel mechanism underlying the action of HDACi that could be potentially useful in the clinical setting. [Mol Cancer Ther 2009;8(11):3108–16]