bluuebunny/crossref_metadata_2025 huggingface dataset:
Study and Optimization of Self‐Assembled Polymeric Multilayer Structures with Neutral Red for pH Sensing Applications
Authors: Goicoechea Javier , Arregui Francisco J. , Corres Jesus M. , Matias Ignacio R.
Published: November 2007

The characterization of nanostructured thin films is critical in the design and fabrication of optical sensors. Particularly, this work is a detailed study of the properties of layer‐by‐layer electrostatic self‐assembled multilayer (LbL) structures fabricated using poly(allylamine hydrochloride) (PAH) and Neutral Red (NR) as cations, and poly(acrylic acid) (PAA) as polyanion. These LbL films, due to the colorimetric properties of the NR, are suitable for sensor applications such as pH sensing in the physiological range. In the (PAH+NR/PAA) LbL structure, it has been observed a very important influence of the pH of the solutions in the properties of the resultant films. Different techniques such as spectroscopy and atomic force microscopy (AFM) are combined to characterize the films, and the results are analyzed showing coherence with previous works. The LbL structure is finally optimized and dramatically improved nanostructured films were fabricated, showing good sensing properties, short response times, and good stability.
Audio Interaction in Computer Mediated Games
Authors: Parker J. R. , Heerema John
Published: November 2007

The use of sound in an interactive media environment has not been advanced, as a technology, as far as graphics or artificial intelligence. This discussion will explore the use of sound as a way to influence the player of a computer game, will show ways that a game can use sound as input, and will describe ways that the player can influence sound in a game. The role of sound in computer games will be explored some practical design ideas that can be used to improve the current state of the art will be given.
Endostatin Binding to Ovarian Cancer Cells Inhibits Peritoneal Attachment and Dissemination
Authors: Yokoyama Yumi , Sedgewick Gerald , Ramakrishnan S.
Published: November 2007

Ovarian cancer cells use integrins to attach to the peritoneal wall. Integrin α5β1 is also the target for the angiogenesis inhibitor, endostatin. Therefore, the ability of endostatin to competitively inhibit tumor cell seeding of the peritoneum was investigated. An imaging method was developed to determine early phases of peritoneal dissemination of ovarian cancer cells. Using this method, endostatin was found to bind ovarian cancer cells through integrin α5β1 and inhibit vessel cooption efficiently. Although both angiostatin and endostatin are potent inhibitors of tumor angiogenesis, peritoneal attachment and vessel cooption was blocked only by the endostatin. Knocking down the expression of integrins α5 and β1 in ovarian cancer cells interfered with endostatin-mediated inhibition of peritoneal seeding. Furthermore, adenovirus-mediated in situ expression of endostatin either inside the peritoneum or by the ovarian tumor cells inhibited peritoneal seeding and dissemination in vivo. Endostatin treatment also prevented primary ovarian cancer cells from attaching to mouse peritoneal wall. These studies show a paraendothelial mechanism by which endostatin can inhibit peritoneal dissemination of ovarian cancer cells and raises the possibility of intraperitoneal expression of endostatin to reduce recurrence. [Cancer Res 2007;67(22):10813–22]
Examination of IGF2 and H19 Loss of Imprinting in Bladder Cancer
Authors: Byun Hyang-Min , Wong Hui-Lee , Birnstein Elliott Aaron , Wolff Erika M. , Liang Gangning , Yang Allen S.
Published: November 2007

Loss of imprinting (LOI) is a common epigenetic event in cancer and may serve as an early biomarker in some cancers. To obtain a better understanding of LOI, we studied 41 bladder tumors and their adjacent normal bladder mucosa. We found 2/9 (22.2%) cases that displayed LOI of IGF2 and 2/16 (12.5%) that had LOI of H19, as determined by the evaluation of mRNA for biallelic expression. In addition, we examined allele-specific methylation of the differentially methylated regions (DMR) of IGF2 and H19 using a new allele-specific pyrosequencing assay. We found that DNA methylation changes were a common finding (21/30, 70%) in the DMR regions, but could not clearly link DNA methylation changes with LOI as measured by biallelic expression. LOI and allele-specific DNA methylation changes are present in bladder cancer; however, a better understanding of the biology of LOI and its relationship to DNA methylation changes is needed before its use as an epigenetic biomarker. [Cancer Res 2007;67(22):10753–8]
Silencing of Prion Protein Sensitizes Breast Adriamycin-Resistant Carcinoma Cells to TRAIL-Mediated Cell Death
Authors: Meslin Franck , Hamaï Ahmed , Gao Ping , Jalil Abdelali , Cahuzac Nathalie , Chouaib Salem , Mehrpour Maryam
Published: November 2007

We investigated the relationship between the resistance to the proapoptotic action of tumor necrosis factor–related apoptosis inducing ligand (TRAIL) and cellular prion protein (PrPc) function, using the TRAIL-sensitive MCF-7 human breast adenocarcinoma cell line and two TRAIL-resistant sublines: 2101 and MCF-7/ADR. All of the cell lines tested expressed TRAIL-R1 and TRAIL-R2. TRAIL decoy receptors were not detected, suggesting that the resistance of 2101 and MCF-7/ADR cells, strongly expressing PrPc, to TRAIL-mediated cell death was independent from the expression of TRAIL receptors and death-inducing signaling complex formation. Down-regulation of PrPc by small interfering RNA increased the sensitivity of Adriamycin- and TRAIL-resistant cells to TRAIL, but not to epirubicin/Adriamycin. TRAIL-mediated apoptosis in PrPc knocked-down cells was associated with caspase processing, Bid cleavage, and Mcl-1 degradation. In addition, an increased sensitivity of apoptosis-resistant cells to TRAIL after PrPc silencing was not associated with the increased recruitment of receptors and intracellular signaling molecule to the death-inducing signaling complex. Bcl-2 expression was substantially decreased after PrPc knock-down but the levels of Bcl-XL and Mcl-1 were not affected. The down-regulation of Bcl-2 was concomitant with Bax delocalization. Our findings support the notion that silencing of PrPc facilitates the activation of proapoptotic Bax by down-regulation of Bcl-2 expression, thereby abolishing the resistance of breast cancer cells to TRAIL-induced apoptosis. [Cancer Res 2007;67(22):10910–9]
Reactive Oxygen Species Regulate Angiogenesis and Tumor Growth through Vascular Endothelial Growth Factor
Authors: Xia Chang , Meng Qiao , Liu Ling-Zhi , Rojanasakul Yongyut , Wang Xin-Ru , Jiang Bing-Hua
Published: November 2007

Reactive oxygen species (ROS) are associated with multiple cellular functions such as cell proliferation, differentiation, and apoptosis. However, the direct roles of endogenous ROS production still remain to be elucidated. In this study, we found that high levels of ROS were spontaneously produced by ovarian and prostate cancer cells. This elevated ROS production was inhibited by NADPH oxidase inhibitor diphenylene iodonium (DPI) and mitochondria electron chain inhibitor rotenone in the cells. To further analyze the source of ROS production, we found that ovarian cancer cells have much higher expression of NOX4 NADPH oxidase, and that specific inhibition of NADPH oxidase subunit p47phox diminished ROS production. To analyze the functional relevance of ROS production, we showed that ROS regulated hypoxia-inducible factor 1 (HIF-1) and vascular endothelial growth factor (VEGF) expression in ovarian cancer cells. Elevated levels of endogenous ROS were required for inducing angiogenesis and tumor growth. NOX4 knockdown in ovarian cancer cells decreased the levels of VEGF and HIF-1α and tumor angiogenesis. This study suggests a new mechanism of higher ROS production in ovarian cancer cells and provides strong evidence that endogenous ROS play an important role for cancer cells to induce angiogenesis and tumor growth. This information may be useful to understand the new mechanism of cancer cells in inducing tumorigenesis and to develop new therapeutic strategy by targeting ROS signaling in human cancer in the future. [Cancer Res 2007;67(22):10823–30]
Activation of Hepatic Stem Cell Marker EpCAM by Wnt–β-Catenin Signaling in Hepatocellular Carcinoma
Authors: Yamashita Taro , Budhu Anuradha , Forgues Marshonna , Wang Xin Wei
Published: November 2007

The heterogeneous nature of hepatocellular carcinoma (HCC) and the lack of appropriate biomarkers have hampered patient prognosis and treatment stratification. Using a gene expression profiling approach, we recently identified a novel prognostic HCC subtype that resembles hepatic progenitor cells with the activation of stem cell markers and Wnt–β-catenin signaling, based on EpCAM (epithelial cell adhesion molecule, a hepatic stem cell marker) expression. In this study, we investigated whether the activation of the Wnt–β-catenin pathway regulates EpCAM expression. We found that nuclear accumulation of β-catenin induced, whereas the degradation of β-catenin or inhibition of Tcf/β-catenin complex formation reduced EpCAM gene expression in cultured normal human hepatocytes and HCC cell lines. We identified two Tcf binding elements in the EpCAM promoter that specifically bound to Tcf-4 in an electrophoretic mobility shift assay. EpCAM promoter luciferase activity was down-regulated by the degradation of β-catenin or inhibition of Tcf/β-catenin complex formation. Furthermore, we found that EpCAM-positive HCC is much more sensitive to Tcf/β-catenin binding inhibitors than EpCAM-negative HCC in vitro. Taken together, our data indicate that EpCAM is a Wnt–β-catenin signaling target gene and may be used to facilitate HCC prognosis by enabling effective stratification of patients with predicted pharmacologic responses to Wnt–β-catenin signaling antagonists. [Cancer Res 2007;67(22):10831–9]
Probabilistic Modeling of DNA Mismatch Repair Effects on Cell Cycle Dynamics and Iododeoxyuridine-DNA Incorporation
Authors: Gurkan Evren , Schupp Jane E. , Aziz Mohammad A. , Kinsella Timothy J. , Loparo Kenneth A.
Published: November 2007

Previous studies in our laboratory have described increased and preferential radiosensitization of mismatch repair-deficient (MMR−) HCT116 colon cancer cells with 5-iododeoxyuridine (IUdR). Indeed, our studies showed that MMR is involved in the repair (removal) of IUdR-DNA, principally the G:IU mispair. Consequently, we have shown that MMR− cells incorporate 25% to 42% more IUdR than MMR+ cells, and that IUdR and ionizing radiation (IR) interact to produce up to 3-fold greater cytotoxicity in MMR− cells. The present study uses the integration of probabilistic mathematical models and experimental data on MMR− versus MMR+ cells to describe the effects of IUdR incorporation upon the cell cycle for the purpose of increasing IUdR-mediated radiosensitivity in MMR− cells. Two computational models have been developed. The first is a stochastic model of the progression of cell cycle states, which is applied to experimental data for two synchronized isogenic MMR+ and MMR− colon cancer cell lines treated with and without IUdR. The second model defines the relation between the percentage of cells in the different cell cycle states and the corresponding IUdR-DNA incorporation at a particular time point. These models can be combined to predict IUdR-DNA incorporation at any time in the cell cycle. These mathematical models will be modified and used to maximize therapeutic gain in MMR− tumors versus MMR+ normal tissues by predicting the optimal dose of IUdR and optimal timing for IR treatment to increase the synergistic action using xenograft models and, later, in clinical trials. [Cancer Res 2007;67(22):10993–11000]
16-kDa Prolactin Inhibits Endothelial Cell Migration by Down-Regulating the Ras-Tiam1-Rac1-Pak1 Signaling Pathway
Authors: Lee Sok-Hyong , Kunz Jeannette , Lin Sue-Hwa , Yu-Lee Li-yuan
Published: November 2007

Angiogenesis plays a key role in promoting tumorigenesis and metastasis. The 16-kDa fragment of prolactin (16k PRL) is an NH2-terminal natural breakdown fragment of the intact 23-kDa prolactin and has been shown to have potent antiangiogenic and antitumor activities. The mechanism(s) involved in the action of 16k PRL in endothelial cells remains unclear. In this study, we showed that 16k PRL reduced rat aortic endothelial cell (RAEC) migration in a wound-healing assay and in a Matrigel tube formation assay, suggesting that 16k PRL inhibits endothelial cell migration, an important activity involved in angiogenesis and tumorigenesis. We further investigated how 16k PRL attenuates endothelial cell migration. We first showed that RAEC migration is mediated through the Rho GTPase Rac1, as Rac1 inhibition by the Rac1-specific inhibitor NSC27366 or Rac1 knockdown by small interfering RNA both blocked RAEC migration. We next showed that 16k PRL reduced the activation of Rac1 in a concentration-dependent manner. Furthermore, 16k PRL inhibition of Rac1 is mediated through the suppression of T lymphoma invasion and metastasis 1 (Tiam1) and its upstream activator Ras in a phosphoinositide-3-kinase–independent manner. 16k PRL also down-regulated the phosphorylation of the downstream effector of Rac1, p21-activating kinase 1 (Pak1), and inhibited its translocation to the leading edge of migrating cells. Thus, 16k PRL inhibits cell migration by blocking the Ras-Tiam1-Rac1-Pak1 signaling pathway in endothelial cells. [Cancer Res 2007;67(22):11045–53]
Placental Growth Factor-1 Attenuates Vascular Endothelial Growth Factor-A–Dependent Tumor Angiogenesis during β Cell Carcinogenesis
Authors: Schomber Tibor , Kopfstein Lucie , Djonov Valentin , Albrecht Imke , Baeriswyl Vanessa , Strittmatter Karin , Christofori Gerhard
Published: November 2007

Members of the vascular endothelial growth factor (VEGF) family are critical players in angiogenesis and lymphangiogenesis. Although VEGF-A has been shown to exert fundamental functions in physiologic and pathologic angiogenesis, the exact role of the VEGF family member placental growth factor (PlGF) in tumor angiogenesis has remained controversial. To gain insight into PlGF function during tumor angiogenesis, we have generated transgenic mouse lines expressing human PlGF-1 in the β cells of the pancreatic islets of Langerhans (Rip1PlGF-1). In single-transgenic Rip1PlGF-1 mice, intra-insular blood vessels are found highly dilated, whereas islet physiology is unaffected. Upon crossing of these mice with the Rip1Tag2 transgenic mouse model of pancreatic β cell carcinogenesis, tumors of double-transgenic Rip1Tag2;Rip1PlGF-1 mice display reduced growth due to attenuated tumor angiogenesis. The coexpression of transgenic PlGF-1 and endogenous VEGF-A in the β tumor cells of double-transgenic animals causes the formation of low-angiogenic hPlGF-1/mVEGF-A heterodimers at the expense of highly angiogenic mVEGF-A homodimers resulting in diminished tumor angiogenesis and reduced tumor infiltration by neutrophils, known to contribute to the angiogenic switch in Rip1Tag2 mice. The results indicate that the ratio between the expression levels of two members of the VEGF family of angiogenic factors, PlGF-1 and VEGF-A, determines the overall angiogenic activity and, thus, the extent of tumor angiogenesis and tumor growth. [Cancer Res 2007;67(22):10840–8]
Overexpression of N-Myc Rapidly Causes Acute Myeloid Leukemia in Mice
Authors: Kawagoe Hiroyuki , Kandilci Ayten , Kranenburg Tanya A. , Grosveld Gerard C.
Published: November 2007

N-MYC encodes a basic helix-loop-helix/leucine zipper (bHLH/LZ) transcription factor that is frequently overexpressed in human neuroblastoma. N-MYC overexpression has also been reported in human acute myeloid leukemias (AML), which we show here is a frequent event. Myeloid cells in N-Myc–overexpressing mouse bone marrow hyperproliferate but those in c-MYC–overexpressing bone marrow do not. The NH2-terminal transactivation domain, nuclear localization signal, and bHLH/LZ domain of N-Myc are essential for this effect. Microarray analysis revealed 969 differentially expressed genes between N-Myc– and c-MYC–overexpressing myeloid cells. N-Myc–overexpressing cells showed decreased transforming growth factor β signaling and increased c-Jun-NH2-kinase signaling, both of which are associated with proliferation and leukemic transformation of myeloid cells. Mice transplanted with bone marrow expressing wild-type N-Myc developed clonal and transplantable AML after ∼1 month; those transplanted with bone marrow expressing mutant N-Myc did not. Twist, a known suppressor of the p19Arf/p53 pathway, was up-regulated in all tumors. These results show that N-Myc overexpression is highly oncogenic in mouse myeloid cells and suggest that N-MYC up-regulation contributes to human myeloid leukemogenesis. [Cancer Res 2007;67(22):10677–85]
Transient Receptor Potential Melastatin 7–like Current in Human Head and Neck Carcinoma Cells: Role in Cell Proliferation
Authors: Jiang Jie , Li Ming-Hua , Inoue Koichi , Chu Xiang-Ping , Seeds Joshua , Xiong Zhi-Gang
Published: November 2007

Ion channels are involved in normal physiologic processes and in the pathology of various diseases. In this study, we investigated the presence and potential function of transient receptor potential melastatin 7 (TRPM7) channels in the growth and proliferation of FaDu and SCC25 cells, two common human head and neck squamous carcinoma cell lines, using a combination of patch-clamp recording, Western blotting, immunocytochemistry, small interfering RNA (siRNA), fluorescent Ca2+ imaging, and cell counting techniques. Although voltage-gated K+ currents were recorded in all cells, none of FaDu cells express voltage-gated Na+ or Ca2+ currents. Perfusion of cells with NMDA or acidic solution did not activate inward currents, indicating a lack of NMDA receptor and acid-sensing channels. Lowering extracellular Ca2+, however, induced a large nondesensitizing current reminiscent of Ca2+-sensing cation current or TRPM7 current previously described in other cells. This Ca2+-sensing current can be inhibited by Gd3+, 2-aminoethoxydiphenyl borate (2-APB), or intracellular Mg2+, consistent with the TRPM7 current being activated. Immunocytochemistry, Western blot, and reverse transcription-PCR detected the expression of TRPM7 protein and mRNA in these cells. Transfection of FaDu cells with TRPM7 siRNA significantly reduced the expression of TRPM7 mRNA and protein as well as the amplitude of the Ca2+-sensing current. Furthermore, we found that Ca2+ is critical for the growth and proliferation of FaDu cells. Blockade of TRPM7 channels by Gd3+ and 2-APB or suppression of TRPM7 expression by siRNA inhibited the growth and proliferation of these cells. Similar to FaDu cells, SCC25 cells also express TRPM7-like channels. Suppressing the function of these channels inhibited the proliferation of SCC25 cells. [Cancer Res 2007;67(22):10929–38]
Lymphoma Chemovirotherapy: CD20-Targeted and Convertase-Armed Measles Virus Can Synergize with Fludarabine
Authors: Ungerechts Guy , Springfeld Christoph , Frenzke Marie E. , Lampe Johanna , Johnston Patrick B. , Parker William B. , Sorscher Eric J. , Cattaneo Roberto
Published: November 2007

Combination chemotherapy regimen incorporating CD20 antibodies are commonly used in the treatment of CD20-positive non–Hodgkin's lymphoma (NHL). Fludarabine phosphate (F-araAMP), cyclophosphamide, and CD20 antibodies (Rituximab) constitute the FCR regimen for treating selected NHL, including aggressive mantle cell lymphoma (MCL). As an alternative to the CD20 antibody, we generated a CD20-targeted measles virus (MV)–based vector. This vector was also armed with the prodrug convertase purine nucleoside phosphorylase (PNP) that locally converts the active metabolite of F-araAMP to a highly diffusible substance capable of efficiently killing bystander cells. We showed in infected cells that early prodrug administration controls vector spread, whereas late administration enhances cell killing. Control of spread by early prodrug administration was also shown in an animal model: F-araAMP protected genetically modified mice susceptible to MV infection from a potentially lethal intracerebral challenge. Enhanced oncolytic potency after extensive infection was shown in a Burkitt's lymphoma xenograft model (Raji cells): After systemic vector inoculation, prodrug administration enhanced the therapeutic effect synergistically. In a MCL xenograft model (Granta 519 cells), intratumoral (i.t.) vector administration alone had high oncolytic efficacy: All mice experienced complete but temporary tumor regression, and survival was two to four times longer than that of untreated mice. Cells from MCL patients were shown to be sensitive to infection. Thus, synergy of F-araAMP with a PNP-armed and CD20-targeted MV was shown in one lymphoma therapy model after systemic vector inoculation. [Cancer Res 2007;67(22):10939–47]
Cell Cycle–Dependent Nuclear Export of Phosphatase and Tensin Homologue Tumor Suppressor Is Regulated by the Phosphoinositide-3-Kinase Signaling Cascade
Authors: Liu Juinn-Lin , Mao Zhenyu , LaFortune Tiffany A. , Alonso Marta M. , Gallick Gary E. , Fueyo Juan , Yung W.K. Alfred
Published: November 2007

The tumor suppressor phosphatase and tensin homologue (PTEN) plays distinct growth-regulatory roles in the cytoplasm and nucleus. It has been shown to be preferentially localized to the nucleus in differentiated or resting cells, and to the cytoplasm in advanced tumor cells. Thus, the regulation of PTEN's subcellular localization seems to be critical to its tumor-suppressing functions. In this study, we showed that activation of the phosphoinositide-3-kinase (PI3K) pathway triggers PTEN's cell cycle–dependent chromosome region maintenance 1–mediated nuclear export, as PTEN was predominantly expressed in the cytoplasm of TSC2−/− mouse embryo fibroblasts or activated Akt mutant-transfected NIH3T3 cells. In contrast, dominant-negative mutants of Akt and pharmacologic inhibitors of PI3K, mTOR, and S6K1, but not of MEK, suppressed the nuclear export of PTEN during the G1-S transition. The nuclear-cytoplasmic trafficking of exogenous PTEN is likewise regulated by the PI3K cascade in PTEN-null U251MG cells. The nuclear export of PTEN could also be blocked by short interfering RNA to S6K1/2. In addition, PTEN interacts with both S6K1 and S6K2. Taken together, our findings strongly indicate that activation of the PI3K/Akt/mTOR/S6K cascade, specifically S6K1/2, is pivotal in regulating the subcellular localization of PTEN. This scenario exemplifies a reciprocal regulation between PI3K and PTEN that defines a novel negative-feedback loop in cell cycle progression. [Cancer Res 2007;67(22):11054–63]
Heat Shock Protein B8, a Cyclin-Dependent Kinase–Independent Cyclin D1 Target Gene, Contributes to Its Effects on Radiation Sensitivity
Authors: Trent Sally , Yang Chuanwei , Li Cuiqi , Lynch Mary , Schmidt Emmett V.
Published: November 2007

Overexpression of cyclin D1 is associated with many cancers, and its overexpression is especially associated with a poor prognosis in breast cancer. Paradoxically, cyclin D1 is known to enhance radiation sensitivity, a finding that has not yet been therapeutically exploited. Proposed cyclin D1 functions that could be involved in this effect include cyclin-dependent kinase (CDK)–dependent phosphorylation of retinoblastoma gene product (pRb), titration of p21/p27 complexes, and less well-characterized effects on gene expression. In this report, we sought to clarify the functions of cyclin D1 that might contribute to enhanced radiation sensitivity. Breast cancer cells stably overexpressing a cyclin D1 mutant (KE) that cannot interact with its CDK partners to phosphorylate pRb were as radiation sensitive as those expressing wild-type D1. Although cyclin D1 has been proposed to affect radiation sensitivity through interactions with p21, a cyclin D1 mutant defective for p21 interactions also increased radiation sensitivity. Cyclin D1 overexpression is generally confined to hormone receptor–positive breast cancers, wherein standard therapies include both radiation and hormonal therapies. Among several proposed CDK-independent cyclin D1 targets, we have identified heat shock protein B8 (HSPB8) as a target particularly associated with cyclin D1 and ER-positive tumors. We therefore evaluated its potential contribution to radiation sensitivity. Overexpression of HSPB8 markedly increased radiation sensitivity, and HSPB8 small interfering RNA blocked cyclin D1's enhancement of radiation sensitivity. Taken together, our results show that some of cyclin D1's effects on radiation sensitivity are CDK and p21 independent and identify HSPB8 as a candidate CDK-independent cyclin D1 target that can mediate its effects. [Cancer Res 2007;67(22):10774–81]
Integrated Endoplasmic Reticulum Stress Responses in Cancer
Authors: Moenner Michel , Pluquet Olivier , Bouchecareilh Marion , Chevet Eric
Published: November 2007

The endoplasmic reticulum (ER) has emerged as a major site of cellular homeostasis regulation, particularly in the unfolded protein response, which is being found to play a major role in cancer and many other diseases. Here, we address ER-mediated signaling and regulations in the context of environmental challenges in cancer, such as hypoxia, angiogenesis, and chemotherapeutic resistance, and we discuss how ER-resident molecular machines become deregulated and involved in cancer-related pathology. Further exploration of how the ER senses, signals, and adapts to stress may redefine and deepen our understanding of its functions in cancer pathobiology. [Cancer Res 2007;67(22):10631–4]
Gene Expression Analysis of Angioimmunoblastic Lymphoma Indicates Derivation from T Follicular Helper Cells and Vascular Endothelial Growth Factor Deregulation
Authors: Piccaluga Pier Paolo , Agostinelli Claudio , Califano Andrea , Carbone Antonino , Fantoni Luca , Ferrari Sergio , Gazzola Anna , Gloghini Annunziata , Righi Simona , Rossi Maura , Tagliafico Enrico , Zinzani Pier Luigi , Zupo Simonetta , Baccarani Michele , Pileri Stefano A.
Published: November 2007

Angioimmunoblastic lymphoma (AILT) is the second most common subtype of peripheral T-cell lymphoma (PTCL) and is characterized by dismal prognosis. Thus far, only a few studies have dealt with its molecular pathogenesis. We performed gene expression profile (GEP) analysis of six AILT, six anaplastic large cell lymphomas (ALCL), 28 PTCL-unspecified (PTCL/U), and 20 samples of normal T lymphocytes (including CD4+, CD8+, and activated and resting subpopulations), aiming to (a) assess the relationship of AILT with other PTCLs, (b) establish the relationship between AILT and normal T-cell subsets, and (c) recognize the cellular programs deregulated in AILT possibly looking for novel potential therapeutic targets. First, we found that AILT and other PTCLs have rather similar GEP, possibly sharing common oncogenic pathways. Second, we found that AILTs are closer to activated CD4+, rather than to resting or CD8+ lymphocytes. Furthermore, we found that the molecular signature of follicular T helper cells was significantly overexpressed in AILT, reinforcing the idea that AILT may arise from such cellular counterpart. Finally, we identified several genes deregulated in AILT, including PDGFRA, REL, and VEGF. The expression of several molecules was then studied by immunohistochemistry on tissue microarrays containing 45 independent AILT cases. Notably, we found that the vascular endothelial growth factor (VEGF) was expressed not only by reactive cells, but also by neoplastic cells, and that nuclear factor-κB (NF-κB) activation is uncommon in AILT, as suggested by frequent exclusively cytoplasmic c-REL localization. Our study provides new relevant information on AILT biology and new candidates for possible therapeutic targets such as PDGFRA (platelet-derived growth factor α) and VEGF. [Cancer Res 2007;67(22):10703–10]
Childhood Social Environment and Risk of Non–Hodgkin Lymphoma in Adults
Authors: Smedby Karin Ekström , Hjalgrim Henrik , Chang Ellen T. , Rostgaard Klaus , Glimelius Bengt , Adami Hans-Olov , Melbye Mads
Published: November 2007

Better hygiene and sanitation and decreasing family size parallel the increasing incidence of non–Hodgkin lymphoma (NHL) in many populations around the world. However, whether sibship size, birth order, and crowding are related to adult NHL risk is not clear. We investigated how family structure and childhood social environment were related to the risk of NHL and NHL subtypes in a large Scandinavian population–based case control study with 6,242 participants aged 18 to 74 years. Detailed exposure information was obtained through telephone interviews. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using logistic regression, and all statistical tests were two-sided. Having four or more siblings was associated with a moderately increased risk of NHL, compared with having no siblings (OR 1.34, 95% CI 1.11-1.62, Ptrend < 0.001). Having four or more older siblings was associated with a similar risk increase (OR 1.33, 95% CI 1.12-1.59, Ptrend = 0.003) compared with being the oldest, whereas number of younger siblings was unrelated overall. The associations were independent of other environmental exposures and did not vary by country, age, or sex. High household crowding was also positively associated with risk of NHL. Results were slightly stronger for diffuse large B-cell and T-cell lymphomas than for other major NHL subtypes. Our findings add to the evidence that large sibship size, late birth order, and childhood crowding are associated with an elevated risk of NHL. Effect mechanisms may be related to early age at onset and high frequency of specific infections or total microbial exposure in childhood. [Cancer Res 2007;67(22):11074–82]
Microtubule Disruption and Tumor Suppression by Mitogen-Activated Protein Kinase Phosphatase 4
Authors: Liu Yuangang , Lagowski James , Sundholm Aaron , Sundberg Alexandra , Kulesz-Martin Molly
Published: November 2007

The extracellular signal-regulated kinase (Erk) is one of the downstream effectors of the Ras pathway whose activation is essential for the proliferation and survival of cancer cells. Erk activation is negatively regulated by mitogen-activated protein kinase (MAPK) phosphatases (MKP), which are generally up-regulated by Erk activation, thus forming a feedback loop for regulation of Erk activity. In searching for early alterations in the Ras pathway in epidermal carcinogenesis, we identified MKP4, a cytosolic MKP with specificity to not only Erk, but also, to a lesser extent, c-jun-NH2-kinase and p38. MKP4 is down-regulated at initiation and lost at malignant conversion in a clonal model of epidermal carcinogenesis that lacks Ras mutation. The loss of MKP4 was associated with squamous cell carcinoma (SCC) but not benign papilloma clonal lineages and with independently induced SCC relative to benign tumors in mouse skin. Reconstitution of MKP4 expression in malignant tumor cells leads to cell death and tumor suppression. Unlike Erk inhibition that blocks cell cycle entry, MKP4 reconstitution resulted in G2-M associated cell death and microtubule disruption. Thus, microtubule disruption by MKP4 provides a novel mechanism for tumor suppression by a cytosolic MKP and implies a novel therapeutic strategy through combined MAPK inhibitions that mimic the function of MKP4. [Cancer Res 2007;67(22):10711–9]
The Oncogenic microRNA-27a Targets Genes That Regulate Specificity Protein Transcription Factors and the G2-M Checkpoint in MDA-MB-231 Breast Cancer Cells
Authors: Mertens-Talcott Susanne U. , Chintharlapalli Sudhakar , Li Xiangrong , Safe Stephen
Published: November 2007

There is evidence that specificity proteins (Sp), such as Sp1, Sp3, and Sp4, are overexpressed in tumors and contribute to the proliferative and angiogenic phenotype associated with cancer cells. Sp1, Sp3, and Sp4 are expressed in a panel of estrogen receptor (ER)–positive and ER-negative breast cancer cell lines, and we hypothesized that regulation of their expression may be due to microRNA-27a (miR-27a), which is also expressed in these cell lines and has been reported to regulate the zinc finger ZBTB10 gene, a putative Sp repressor. Transfection of ER-negative MDA-MB-231 breast cancer cells with antisense miR-27a (as-miR-27a) resulted in increased expression of ZBTB10 mRNA and decreased expression of Sp1, Sp3, and Sp4 at the mRNA and protein levels and also decreased activity in cells transfected with constructs containing Sp1 and Sp3 promoter inserts. In addition, these responses were accompanied by decreased expression of Sp-dependent survival and angiogenic genes, including survivin, vascular endothelial growth factor (VEGF), and VEGF receptor 1 (VEGFR1). Moreover, similar results were observed in MDA-MB-231 cells transfected with ZBTB10 expression plasmid. Both as-miR-27a and ZBTB10 overexpression decreased the percentage of MDA-MB-231 cells in S phase of the cell cycle; however, ZBTB10 increased the percentage of cells in G0-G1, whereas as-miR-27a increased the percentage in G2-M. This latter response was associated with induction of Myt-1 (another miR-27a target gene), which inhibits G2-M through enhanced phosphorylation and inactivation of cdc2. Thus, the oncogenic activity of miR-27a in MDA-MB-231 cells is due, in part, to suppression of ZBTB10 and Myt-1. [Cancer Res 2007;67(22):11001–11]
KCl Cotransporter-3 Down-regulates E-Cadherin/β-Catenin Complex to Promote Epithelial-Mesenchymal Transition
Authors: Hsu Yueh-Mei , Chen Yih-Fung , Chou Cheng-Yang , Tang Ming-Jer , Chen Ji Hshiung , Wilkins Robert J. , Ellory J. Clive , Shen Meng-Ru
Published: November 2007

The potassium chloride cotransporter (KCC) is a major determinant of osmotic homeostasis and plays an emerging role in tumor biology. Here, we investigate if KCC is involved in the regulation of epithelial-mesenchymal transition (EMT), a critical cellular event of malignancy. E-cadherin and β-catenin colocalize in the cell-cell junctions, which becomes more obvious in a time-dependent manner by blockade of KCC activity in cervical cancer SiHa and CaSki cells. Real-time reverse transcription-PCR on the samples collected from the laser microdissection indicates that KCC3 is the most abundant KCC isoform in cervical carcinoma. The characteristics of EMT appear in KCC3-overexpressed, but not in KCC1- or KCC4-overexpressed cervical cancer cells, including the elongated cell shape, increased scattering, down-regulated epithelial markers (E-cadherin and β-catenin), and up-regulated mesenchymal marker (vimentin). Some cellular functions are enhanced by KCC3 overexpression, such as increased invasiveness and proliferation, and weakened cell-cell association. KCC3 overexpression decreases mRNA level of E-cadherin. The promoter activity assays of various regulatory sequences confirm that KCC3 expression is a potent negative regulator for human E-cadherin gene expression. The proteosome inhibitor restores the decreased protein abundance of β-catenin by KCC3 overexpression. In the surgical specimens of cervical carcinoma, the decreased E-cadherin amount was accompanied by the increased KCC3 abundance. Vimentin begins to appear at the invasive front and becomes significantly expressed in the tumor nest. In conclusion, KCC3 down-regulates E-cadherin/β-catenin complex formation by inhibiting transcription of E-cadherin gene and accelerating proteosome-dependent degradation of β-catenin protein. The disruption of E-cadherin/β-catenin complex formation promotes EMT, thereby stimulating tumor progression. [Cancer Res 2007;67(22):11064–73]
Mechanism of All-TransRetinoic Acid Effect on Tumor-Associated Myeloid-Derived Suppressor Cells
Authors: Nefedova Yulia , Fishman Mayer , Sherman Simon , Wang Xingyu , Beg Amer A. , Gabrilovich Dmitry I.
Published: November 2007

Myeloid-derived suppressor cells (MDSC) play an important role in tumor escape by suppressing T-cell responses. MDSC represent a group of cells of myeloid lineage at different stages of differentiation. Increased arginase activity and production of reactive oxygen species (ROS) are among the main functional characteristics of these cells. Recent studies have shown that all-trans retinoic acid (ATRA) had a potent activity in eliminating MDSC in cancer patients and in tumor-bearing mice. ATRA differentiates these cells into mature myeloid cells. However, the mechanism of this effect is unclear. Here, we have shown that ATRA dramatically and specifically up-regulated gene expression and protein level of glutathione synthase (GSS) in MDSC. This resulted in accumulation of glutathione (GSH) in these cells, observed in both mice and cancer patients. Blockade of GSH synthesis cancelled the effect of ATRA on MDSC. Accumulation of GSH in these cells using N-acetyl-l-cysteine mimicked the effect of ATRA on MDSC differentiation. Analysis of potential mechanisms of ATRA effect on GSS revealed that ATRA regulates its expression not by directly binding to the promoter but primarily via activation of extracellular signal–regulated kinase 1/2. Thus, ATRA induced differentiation of MDSC primarily via neutralization of high ROS production in these cells. This novel mechanism involves specific up-regulation of GSS and accumulation of GSH and could be used in developing and monitoring therapeutic application of ATRA. [Cancer Res 2007;67(22):11021–8]
Therapeutic Efficacy of a Novel Focal Adhesion Kinase Inhibitor TAE226 in Ovarian Carcinoma
Authors: Halder Jyotsnabaran , Lin Yvonne G. , Merritt William M. , Spannuth Whitney A. , Nick Alpa M. , Honda Toshiyuki , Kamat Aparna A. , Han Liz Y. , Kim Tae Jin , Lu Chunhua , Tari Ana M. , Bornmann William , Fernandez Ariel , Lopez-Berestein Gabriel , Sood Anil K.
Published: November 2007

Focal adhesion kinase (FAK) overexpression is frequently found in ovarian and other cancers and is predictive of poor clinical outcome. In the current study, we characterized the biological and therapeutic effects of a novel FAK inhibitor, TAE226. Taxane-sensitive (SKOV3ip1 and HeyA8) and taxane-resistant (HeyA8-MDR) cell lines were used for in vitro and in vivo therapy experiments using TAE226 alone and in combination with docetaxel. Assessment of cytotoxicity, cell proliferation [proliferating cell nuclear antigen (PCNA)], angiogenesis (CD31), and apoptosis (terminal nucleotidyl transferase–mediated nick end labeling) were done by immunohistochemistry and immunofluorescence. In vitro, TAE226 inhibited the phosphorylation of FAK at both Y397 and Y861 sites, inhibited cell growth in a time- and dose-dependent manner, and enhanced docetaxel-mediated growth inhibition by 10- and 20-fold in the taxane-sensitive and taxane-resistant cell lines, respectively. In vivo, FAK inhibition by TAE226 significantly reduced tumor burden in the HeyA8, SKOV3ip1, and HeyA8-MDR models (46–64%) compared with vehicle-treated controls. However, the greatest efficacy was observed with concomitant administration of TAE226 and docetaxel in all three models (85–97% reduction, all P values <0.01). In addition, TAE226 alone and in combination with chemotherapy significantly prolonged survival in tumor-bearing mice. Even in larger tumors, combination therapy with TAE226 and docetaxel resulted in tumor regression. The therapeutic efficacy was related to reduced pericyte coverage, induction of apoptosis of tumor-associated endothelial cells, and reduced microvessel density and tumor cell proliferation. The novel FAK inhibitor, TAE226, offers an attractive therapeutic approach in ovarian carcinoma. [Cancer Res 2007;67(22):10976–83]
Matrix Metalloproteinases-1 and -8 Improve the Distribution and Efficacy of an Oncolytic Virus
Authors: Mok Wilson , Boucher Yves , Jain Rakesh K.
Published: November 2007

Oncolytic viral vectors show enormous potential for the treatment of many solid tumors. However, these vectors often suffer from insufficient delivery within tumors, which limits their efficacy in both preclinical and clinical settings. We have previously shown that tumor collagen can significantly hinder diffusion, and that its degradation can enhance the distribution and efficacy of an oncolytic herpes simplex virus (HSV) vector. Here, we identify two members of the matrix metalloproteinase (MMP) family of enzymes, MMP-1 and MMP-8, which can modulate the tumor matrix and enhance HSV delivery and efficacy. We show that overexpression of MMP-1 and MMP-8 in the human soft tissue sarcoma HSTS26T leads to a significant depletion of tumor-sulfated glycosaminoglycans. This increases the hydraulic conductivity of these tumors and enhances the flow of virus during injection. In control tumors, injected virus accumulates primarily in the periphery of the tumor. In contrast, we observed a more widespread distribution of virus around the injection site in MMP-1– and MMP-8–expressing tumors. Due to this enhanced vector delivery, MMP-expressing tumors respond significantly better to oncolytic HSV treatment than control tumors. Thus, these findings introduce a new approach to improve the delivery and efficacy of oncolytic viral vectors: modulation of tumor glycosaminoglycans to enhance convection. [Cancer Res 2007;67(22):10664–8]
AMG 102, A Fully Human Anti-Hepatocyte Growth Factor/Scatter Factor Neutralizing Antibody, Enhances the Efficacy of Temozolomide or Docetaxel in U-87 MG Cells and Xenografts
Authors: Jun H. Toni , Sun Jan , Rex Karen , Radinsky Robert , Kendall Richard , Coxon Angela , Burgess Teresa L.
Published: November 2007

Purpose: Hepatocyte growth factor (HGF/SF) and its receptor c-Met have previously been shown to be up-regulated in multiple human cancers, including glioblastoma multiforme. To better understand if AMG 102, a fully human, anti-HGF/SF–neutralizing antibody, could be incorporated into current clinical practice, AMG 102 was tested preclinically in combination with temozolomide or docetaxel to determine if enhanced efficacy was observed compared with AMG 102 alone.

Experimental Design: The effects of AMG 102 were tested for antiproliferative activity in combination with temozolomide or docetaxel on U-87 MG cells in vitro and for antitumor activity in a U-87 MG xenograft model in vivo. Apoptotic activity was also measured for AMG 102 and docetaxel combined in vitro.

Results: Treatment with temozolomide combined with AMG 102 resulted in increased inhibition of cell growth in vitro compared with treatment with either single agent alone. In U-87 MG xenografts in vivo, AMG 102 combined with temozolomide or docetaxel significantly increased the inhibitory effect on tumor growth when compared with treatment with either agent alone (P < 0.0001 and P < 0.015, respectively). In vitro, docetaxel alone induced both caspase-3/7 activity as well as poly(ADP)ribose polymerase and caspase-7 cleavage in U-87 MG cells; these events were enhanced when used in combination with AMG 102. Importantly, there was no evidence of interference between AMG 102 and either temozolomide or docetaxel in vitro or in vivo.

Conclusion: These studies support testing of AMG 102 in combination with temozolomide or docetaxel. Such combinations may represent promising, novel clinical therapeutic strategies for cancers that are dependent on the HGF/SF/SF:c-Met pathway in the oncology setting.
Defining Cancer Cachexia in Head and Neck Squamous Cell Carcinoma
Authors: Richey Luke M. , George Jonathan R. , Couch Marion E. , Kanapkey Brian K. , Yin Xiaoying , Cannon Trinitia , Stewart Paul W. , Weissler Mark C. , Shores Carol G.
Published: November 2007

Purpose: Cancer cachexia is a devastating and understudied illness in patients with head and neck squamous cell carcinoma (HNSCC). The primary objective was to identify clinical characteristics and serum levels of cytokines and cachexia-related factors in patients with HNSCC. The secondary objective was to detect the occurrence of cytokine and cachexia-related factor gene expression in HNSCC tumors.

Experimental Design: For the primary objective, cross-sectional data were obtained from prospectively recruited patients identified as cachexia cases and matching cachexia-free controls. For the secondary objective, a retrospective cohort design with matched controls was used.

Results: Clinical characteristics associated with cancer cachexia in HNSCC were T4 status (P = 0.01), increased C-reactive protein (P = 0.01), and decreased hemoglobin (P < 0.01). Exploratory multiplex analysis of serum cytokine levels found increased interleukin (IL)-6 (P = 0.04). A highly sensitive ELISA confirmed the multiplex result for increased IL-6 in cachectic patients (P = 0.02). Quality of life was substantially reduced in patients with cachexia compared with noncachectic patients (P < 0.01). All tumors of HNSCC patients both with and without cachexia expressed RNA for each cytokine tested and the cachexia factor lipid-mobilizing factor. There were no statistically significant differences between the cytokine and cachexia factor RNA expression of cachectic and noncachectic patients (each P > 0.05). No tumors expressed the cachexia factor proteolysis-inducing factor.

Conclusion: We have identified clinical characteristics and pathophysiologic mechanisms associated with cancer cachexia in a carefully defined population of patients with HNSCC. The data suggest that the acute-phase response and elevated IL-6 are associated with this complex disease state. We therefore hypothesize that IL-6 may represent an important therapeutic target for HNSCC patients with cancer cachexia.
BAG-4/SODD and Associated Antiapoptotic Proteins Are Linked to Aggressiveness of Epithelial Ovarian Cancer
Authors: Annunziata Christina M. , Kleinberg Lilach , Davidson Ben , Berner Aasmund , Gius David , Tchabo Nana , Steinberg Seth M. , Kohn Elise C.
Published: November 2007

Purpose: We hypothesized that elevated expression in ovarian cancer of the BAG family of prosurvival proteins and associated partners would be associated with clinical features of aggressiveness in ovarian cancer.

Experimental Design: Expression patterns of BAG-1, BAG-3, BAG-4, and Bcl-xL were determined by immunohistochemical analysis of tissue samples obtained at diagnosis from 28 women with stage III or stage IV ovarian cancer treated with cisplatin, paclitaxel, and cyclophosphamide after initial cytoreduction. Association of these proteins, BAG-6, heat shock protein 70 (Hsp70), Hsp27, and Bcl-2, with clinical variables was tested in ovarian cancer tissue arrays from Gynecologic Oncology Group tissue bank.

Results: A statistically significant relationship was found between elevated cytoplasmic expression of BAG-4 and improved overall (P = 0.0002) and progression-free survival (P = 0.003) in the prospectively collected samples. Bcl-2 staining was significantly more frequent on the tissue array in lower stage (P = 0.005) and grade (P = 0.0009) tumors, whereas Hsp70 was prominent in higher grade cases (P = 0.002). Furthermore, Bcl-xL was more closely associated with serous compared with endometrioid ovarian cancers (P = 0.004).

Conclusion: Unexpectedly, cytoplasmic expression of BAG-4 and Bcl-2 marked less aggressive ovarian cancer, whereas nuclear Hsp70 suggested more aggressive behavior. Bcl-xL may play a more prominent function in the pathology of serous histology ovarian cancers compared with the endometrioid subtype. The findings presented here support involvement of these proteins in the propagation of ovarian cancer and provide a basis for the development of molecular therapeutics modulating these survival pathways.