bluuebunny/crossref_metadata_2025 huggingface dataset:
Low Overpotential, High Activity: Manganese/ Ruthenium Mixed Oxide Electrocatalysts for Oxygen Evolution in Alkaline Media
Authors: Browne Michelle Phillippa , Colavita Paula E , Lyons Micheal E.G
Published: May 2015

The combination of a platinum group material (i.e. ruthenium) with a first row transition metal (i.e. manganese) could provide stability and lower the cost of OER electrocatalyst, while still obtaining good OER properties. In this work classical electrochemical techniques have been used to study the electrocatalytic properties of thermally prepared manganese, mixed manganese/ruthenium and ruthenium based electrocatalysts on a titanium substrate at three different annealing temperatures for OER. The structure and morphology of the thermally decomposed oxide materials are examined using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy. Turnover Frequency (TOF) numbers are also calculated. The initial OER overpotential values of eight electrocatalysts, in this study, are lower than that of the lowest known OER electrocatalyst, RuO2. All SEM images with 10 – 100 % of RuOx show a mud-cracked morphology. This morphology is attributed to the excellent electrocatalytic activity of RuO2.
Local temperature-sensitive mechanisms are important mediators of limb tissue hyperemia in the heat-stressed human at rest and during small muscle mass exercise
Authors: Chiesa Scott T. , Trangmar Steven J. , Kalsi Kameljit K. , Rakobowchuk Mark , Banker Devendar S. , Lotlikar Makrand D. , Ali Leena , González-Alonso José
Published: May 2015

Limb tissue and systemic blood flow increases with heat stress, but the underlying mechanisms remain poorly understood. Here, we tested the hypothesis that heat stress-induced increases in limb tissue perfusion are primarily mediated by local temperature-sensitive mechanisms. Leg and systemic temperatures and hemodynamics were measured at rest and during incremental single-legged knee extensor exercise in 15 males exposed to 1 h of either systemic passive heat-stress with simultaneous cooling of a single leg ( n = 8) or isolated leg heating or cooling ( n = 7). Systemic heat stress increased core, skin and heated leg blood temperatures (Tb), cardiac output, and heated leg blood flow (LBF; 0.6 ± 0.1 l/min; P < 0.05). In the cooled leg, however, LBF remained unchanged throughout ( P > 0.05). Increased heated leg deep tissue blood flow was closely related to Tb ( R2 = 0.50; P < 0.01), which is partly attributed to increases in tissue V̇O2 ( R2 = 0.55; P < 0.01) accompanying elevations in total leg glucose uptake ( P < 0.05). During isolated limb heating and cooling, LBFs were equivalent to those found during systemic heat stress ( P > 0.05), despite unchanged systemic temperatures and hemodynamics. During incremental exercise, heated LBF was consistently maintained ∼0.6 l/min higher than that in the cooled leg ( P < 0.01), with LBF and vascular conductance in both legs showing a strong correlation with their respective local Tb ( R2 = 0.85 and 0.95, P < 0.05). We conclude that local temperature-sensitive mechanisms are important mediators in limb tissue perfusion regulation both at rest and during small-muscle mass exercise in hyperthermic humans.
Cystathionine γ-lyase, a H2S-generating enzyme, is a GPBAR1-regulated gene and contributes to vasodilation caused by secondary bile acids
Authors: Renga Barbara , Bucci Mariarosaria , Cipriani Sabrina , Carino Adriana , Monti Maria Chiara , Zampella Angela , Gargiulo Antonella , d'Emmanuele di Villa Bianca Roberta , Distrutti Eleonora , Fiorucci Stefano
Published: May 2015

GPBAR1 is a bile acid-activated receptor (BAR) for secondary bile acids, lithocholic (LCA) and deoxycholic acid (DCA), expressed in the enterohepatic tissues and in the vasculature by endothelial and smooth muscle cells. Despite that bile acids cause vasodilation, it is unclear why these effects involve GPBAR1, and the vascular phenotype of GPBAR1 deficient mice remains poorly defined. Previous studies have suggested a role for nitric oxide (NO) in regulatory activity exerted by GPBAR1 in liver endothelial cells. Hydrogen sulfide (H2S) is a vasodilatory agent generated in endothelial cells by cystathionine-γ-lyase (CSE). Here we demonstrate that GPBAR1 null mice had increased levels of primary and secondary bile acids and impaired vasoconstriction to phenylephrine. In aortic ring preparations, vasodilation caused by chenodeoxycholic acid (CDCA), a weak GPBAR1 ligand and farnesoid-x-receptor agonist (FXR), was iberiotoxin-dependent and GPBAR1-independent. In contrast, vasodilation caused by LCA was GPBAR1 dependent and abrogated by propargyl-glycine, a CSE inhibitor, and by 5β-cholanic acid, a GPBAR1 antagonist, but not by N5-(1-iminoethyl)-l-ornithine (l-NIO), an endothelial NO synthase inhibitor, or iberiotoxin, a large-conductance calcium-activated potassium (BKCa) channels antagonist. In venular and aortic endothelial (HUVEC and HAEC) cells GPBAR1 activation increases CSE expression/activity and H2S production. Two cAMP response element binding protein (CREB) sites (CREs) were identified in the CSE promoter. In addition, TLCA stimulates CSE phosphorylation on serine residues. In conclusion we demonstrate that GPBAR1 mediates the vasodilatory activity of LCA and regulates the expression/activity of CSE. Vasodilation caused by CDCA involves BKCa channels. The GPBAR1/CSE pathway might contribute to endothelial dysfunction and hyperdynamic circulation in liver cirrhosis.
Modulation of motor unit activity in biceps brachii by neuromuscular electrical stimulation applied to the contralateral arm
Authors: Amiridis Ioannis G. , Mani Diba , Almuklass Awad , Matkowski Boris , Gould Jeffrey R. , Enoka Roger M.
Published: May 2015

The purpose of the study was to determine the influence of neuromuscular electrical stimulation (NMES) current intensity and pulse width applied to the right elbow flexors on the discharge characteristics of motor units in the left biceps brachii. Three NMES current intensities were applied for 5 s with either narrow (0.2 ms) or wide (1 ms) stimulus pulses: one at 80% of motor threshold and two that evoked contractions at either ∼10% or ∼20% of maximal voluntary contraction (MVC) force. The discharge times of 28 low-threshold (0.4–21.6% MVC force) and 16 high-threshold (31.7–56.3% MVC force) motor units in the short head of biceps brachii were determined before, during, and after NMES. NMES elicited two main effects: one involved transient deflections in the left-arm force at the onset and offset of NMES and the other consisted of nonuniform modulation of motor unit activity. The force deflections, which were influenced by NMES current intensity and pulse width, were observed only when low-threshold motor units were tracked. NMES did not significantly influence the discharge characteristics of tracked single-threshold motor units. However, a qualitative analysis indicated that there was an increase in the number of unique waveforms detected during and after NMES. The findings indicate that activity of motor units in the left elbow flexors can be modulated by NMES current and pulse width applied to right elbow flexors, but the effects are not distributed uniformly to the involved motor units.
A New Experimental Method to Determine the Henry’s Law Constant of a Volatile Organic Compound Adsorbed in Soil
Authors: Ouoba S. , Cherblanc F. , Koulidiati J. , Bénet J.-C.
Published: May 2015

This paper presents a new mechanical method to determine Henry’s law constant (HLC) of a volatile organic compound (VOC). This method is an extension of the one proposed by Ouoba et al. (2010) to determine the water activity in porous media. This work focuses on TCE and aims at characterizing its liquid-vapor equilibrium in various cases in the form of a pure liquid phase or dissolved in an aqueous solution, adsorbed or not in a natural soil. A liquid phase is disposed in a closed chamber whose volume can be incrementally increased. The recording of the total gas pressure leads to evaluating the vapor partial pressure of a volatile compound even in the case of an aqueous solution. This method has been validated using various aqueous solutions of TCE and the HLC obtained is in agreement with the literature. Then, the validity of Henry’s law has been asserted in the case of an aqueous solution of TCE adsorbed in a hygroscopic soil. Indeed, a linear relation between the vapor partial pressure of TCE and its concentration has been obtained while the HLC is about 16% lower. This result highlights the influence of adsorption phenomena on vapor/liquid equilibrium.
Molecular Pathways: A Novel Approach to Targeting Hypoxia and Improving Radiotherapy Efficacy via Reduction in Oxygen Demand
Authors: Lin Alexander , Maity Amit
Published: May 2015

Tumor hypoxia presents a unique therapeutic challenge in the treatment of solid malignancies. Its presence has been established to be a poor prognostic factor in multiple cancer types, and past hypoxia-directed approaches have yielded generally disappointing results. Previous approaches have centered on either increasing oxygen delivery or administering agents that preferentially radiosensitize or kill hypoxic cells. However, a novel and potentially more effective method may be to increase therapeutic benefit by decreasing tumor oxygen consumption via agents such as metformin or nelfinavir in a patient population that is enriched for tumor hypoxia. This promising approach is currently being investigated in clinical trials and the subject of this article. Clin Cancer Res; 21(9); 1995–2000. ©2015 AACR.
PET Imaging in Head and Neck Cancer Patients to Monitor Treatment Response: A Future Role for EGFR-Targeted Imaging
Authors: van Dijk Laura K. , Boerman Otto C. , Kaanders Johannes H.A.M. , Bussink Johan
Published: May 2015

Approximately 50,000 new cases of head and neck squamous cell carcinoma (HNSCC) are diagnosed worldwide each year and subsequently treated with surgery, chemotherapy, radiotherapy, and/or targeted therapy. The heterogeneity of the patient population in terms of treatment response drives the search for tumor-specific biomarkers. Imaging of biomarkers can reveal patient-specific responses to therapies and, if assessed early after the start of treatment, may allow adaptation of treatment regimens. In this review, tracers that have been tested to monitor treatment efficacy in HNSCC by PET scanning prior to and early after the onset of treatment are discussed. An important imaging target for this application in HNSCC patients is the EGFR. It steers the pathways related to proliferation, hypoxia, DNA damage repair, and apoptosis, all treatment-resistance mechanisms. The anti-EGFR antibody cetuximab has been labeled with various radionuclides and has been tested as an imaging biomarker in several HNSCC models. These studies suggest that EGFR-targeting tracers can be used to monitor EGFR receptor expression in HNSCC and have the potential to noninvasively monitor cetuximab treatment and steer individualized treatment regimens. Multiple factors can influence the uptake of EGFR-targeting tracers. Here, we discuss the relevance of gene and protein overexpression, mutations, and amplifications related to EGFR signaling. In addition, monoclonal antibody properties and the effect on the host immune system are reviewed in light of the future role of EGFR-targeted imaging in HNSCC. Clin Cancer Res; 21(16); 3602–9. ©2015 AACR.
Abstract 10: Characterization of CD45-/CD31+/CD105+ circulating cells in the peripheral blood of patients with gynecological malignancies
Authors: Yu Hyun-Kyung , Lee Ho-Jeong , Choi Ha-Na , Ahn Jin-Hyung , Choi Ji-Young , Jeong Eun-Jeong , Seok Hyun-Jeong , Song Haengseok , Lee Ki-Heon , Yi Lee S.H. , Kim Sun Jin , Kim Tae Jin , Kim Jang-Seong
Published: May 2015

Purpose: Circulating endothelial cells (CECs) have been widely used as a prognostic biomarker and regarded as a promising strategy for monitoring the response to treatment in several cancers. However, the presence and biological roles of CECs have remained controversial for decades because technical standards for the identification and quantification of CECs have not been established. Here, we hypothesized that CECs detected by flow cytometry might be monocytes rather than endothelial cells.

Experimental Design: The frequency of representative CEC subsets (i.e., CD45-/CD31+, CD45-/CD31+/CD146+, CD45-/CD31+/CD105+) was analyzed in the peripheral blood of gynecological cancer patients (n=56) and healthy volunteers (n=44). CD45-/CD31+ cells, which are components of CECs, were isolated and the expression of various markers (CD146, CD105, vWF, and CD144 for endothelial cells; CD68 and CD14 for monocytes) was examined by immunocytochemistry.

Results: CD45-/CD31+/CD105+ cells were significantly increased in the peripheral blood of cancer patients whereas evaluation of CD45/CD31+/CD146+ cells was not possible both in cancer patients and healthy controls due to the limited resolution of the flow cytometry. Immunocytochemistry analyses showed that these CD45-/CD31+/CD105+ cells did not express vWF and CD146 but rather CD144. Furthermore, CD45-/CD31+/CD105+ cells uniformly expressed the monocyte-specific markers CD14 and CD68. These results suggest that D45/CD31+/CD105+ cells carry the characteristics of monocytes rather than endothelial cells.

Conclusions: Our data indicate that CD45-/CD31+/CD105+ circulating cells, which are significantly increased in the peripheral blood of gynecological cancer patients, are monocytes rather than endothelial cells. Further investigation is required to determine the biological significance of their presence and function in relation with angiogenesis.

Citation Format: Hyun-Kyung Yu, Ho-Jeong Lee, Ha-Na Choi, Jin-Hyung Ahn, Ji-Young Choi, Eun-Jeong Jeong, Hyun-Jeong Seok, Haengseok Song, Ki-Heon Lee, Lee S.H. Yi, Sun Jin Kim, Tae Jin Kim, Jang-Seong Kim. Characterization of CD45-/CD31+/CD105+ circulating cells in the peripheral blood of patients with gynecological malignancies. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 10. doi:10.1158/1538-7445.AM2014-10
Abstract 1002: Norrin controls colon cancer angiogenesis
Authors: Planutis Kestutis , Planoutene Marina , Holcombe Randall F.
Published: May 2015

The purposes of the study: Colorectal (CRC) tumors depend on mediators in the tumor microenvironment, such as vascular endothelial growth factor, to promote angiogenesis. Norrin is a ligand that binds to the cell surface Frizzled-4 receptor, stimulating canonical Wnt signaling, and is known to mediate blood vessel growth in the eye and ear. We investigate here the role of Norrin secreted by colon cancer cells in endothelial cell growth and motility as well as the expression of the Norrin signaling pathway components in the CRC tumor microenvironment.

Experimental procedures: Primary human umbilical vein endothelial cells (HUVEC) expressing green fluorescent protein and a HUVEC-derived endothelial cell line, EAhy926 were utilized for in vitro angiogenesis assays measuring cell motility and in vitro angiogenesis. Experiments were performed with and without the addition of Norrin-containing conditioned medium from a transfected CRC cell line CaCO2 and with and without blocking anti-Norrin antibodies. Tissue specimens from human CRC patients were evaluated with a double signal amplification system to define the expression of Norrin, Frizzled-4, LRP5 and TSPAN12 in tumor blood vessels.

Summary of data: Blocking generated by the endothelial cells themselves Norrin reduced endothelial cell motility, branch point number during in vitro angiogenesis (1/sq. mm), and the network length (mm/sq. mm) during in vitro angiogenesis. Norrin conditioned medium produced by CRC cell line CaCO2 transfected with Norrin expression construct increased endothelial cell motility. Colorectal tumors express Norrin protein. Endothelial cells in the colorectal tumor blood vessels contain all of the components of the Norrin signaling pathway needed for the endothelial cells to respond to Norrin in the tumor microenvironment.

Statement of the conclusions: This study presents both in vitro and in vivo data that colorectal tumors use Norrin protein as an alternative mechanism that promotes angiogenesis in the CRC tumor microenvironment.

Citation Format: Kestutis Planutis, Marina Planoutene, Randall F. Holcombe. Norrin controls colon cancer angiogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1002. doi:10.1158/1538-7445.AM2014-1002
Abstract 1005: Leptin increases VEGF expression and enhances angiogenesis in human chondrosarcoma cells
Authors: Hsu Kai-Hsiang , Tang Chih-Hsin , Tan Tzu-Wei
Published: May 2015

Leptin, the product of the obese gene that plays an important role in the regulation of body weight that induces neuroprotection, neurogenesis, and angiogenesis. However, the effect of leptin on VEGF expression in human chondrosarcoma cells is mostly unknown. The aim of study is try to examine the effect of leptin in VEGF expression and angiogenesis in human chondrosarcoma cells. We found that exogenous leptin with chondrosarcoma cells promoted VEGF expression and subsequently increased migration and tube formation in endothelial progenitor cells (EPC). Leptin-mediated VEGF and angiogenesis up-regulation were attenuated by OBRl receptor antisense oligonucleotide. In addition, leptin-induced VEGF expression was attenuated by ERK inhibitor (U0126), p38 inhibitor (SB203580), JNK inhibitor (SP600125) and AP-1 inhibitors (Curcumin and Tanshinone). Incubation of cells with leptin induced ERK, p38, JNK and c-Jun phosphorylation as well as AP-1 luciferase activity. Knockdown of leptin decreased VEGF expression and also abolished chondrosarcoma conditional medium-mediated angiogenesis in vitro as well as angiogenesis effects in the matrigel plug model in vivo. In addition, using xenograft tumor angiogenesis model, knockdown leptin significantly reduced tumor growth and tumor angiogenesis. Taken together, our results indicated that leptin enhances the VEGF expression in chondrosarcoma cells. One of the mechanisms underlying leptin-directed VEGF expression was through the ERK/p38/JNK and c-Jun signal transduction pathway.

Citation Format: Kai-Hsiang Hsu, Chih-Hsin Tang, Tzu-Wei Tan. Leptin increases VEGF expression and enhances angiogenesis in human chondrosarcoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1005. doi:10.1158/1538-7445.AM2014-1005
Abstract 1008: Resveratrol causes biphasic apoptotic and proliferative effects and at higher/proapoptotic/anti-angiogenesis concentrations causes suppression of nitric oxide/cGMP/protein kinase G signaling and decreased expression of prosurvival proteins c-IAP1, c-IAP2, livin and XIAP in human umbilical vein endothelial cells
Authors: Wong Janica C. , Coffman Renee , Rosenberg Harry , Fiscus Ronald R.
Published: May 2015

Anti-cancer/anti-angiogenesis effects of resveratrol have been reported. Resveratrol increases nitric oxide (NO) production via increased expression of endothelial-form-NO-synthase (eNOS). However, the role of cGMP/protein kinase G (PKG) signaling, a pathway activated by NO/eNOS, in the anti-angiogenic effects of resveratrol is still unclear. In the present study, involvement of endogenous NO/cGMP/PKG pathway and downstream pro-survival proteins (Inhibitor of Apoptosis Proteins, IAPs) are studied in relation to anti-angiogenic effects of resveratrol in human umbilical vein endothelial cells (HUVECs). Our results show that resveratrol at higher/anti-angiogenesis concentrations (>50 μM) inhibits tube formation and cell migration/invasion. Resveratrol stimulates proliferation/DNA synthesis at lower concentration (10 µM), but inhibits proliferation/DNA synthesis at higher concentrations (100 and 500 µM). Moreover, resveratrol at lower concentrations (10, 20 and 50 µM) protects HUVECs against spontaneous apoptosis, but induces higher-level apoptosis at higher concentration (500 µM). ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one), inhibitor of endogenous NO-induced activation of soluble-guanylyl-cyclase and subsequent cGMP biosynthesis, completely abolishes the anti-apoptotic/cytoprotective effects of low-concentration resveratrol. 8-Br-cGMP, a direct stimulator of PKG kinase-activity, protects against pro-apoptotic effects of high-concentration resveratrol, establishing a cytoprotective role of activated-PKG in HUVECs. Western blot analyses show that higher/pro-apoptotic/anti-angiogenesis concentrations of resveratrol cause suppression of PKG kinase-activity (indicated by decreased VASP phosphorylation at Ser239) and decreased expression of eNOS and four IAPs, c-IAP1, c-IAP2, livin and XIAP. Overall, our results suggest a cytoprotective role of NO/cGMP/PKG signaling in HUVECs and further suggest that resveratrol (>50 μM)-induced anti-angiogenesis/pro-apoptosis involves suppression of NO/cGMP/PKG signaling and decreased expression of pro-survival proteins c-IAP1, c-IAP2, livin and XIAP.

Citation Format: Janica C. Wong, Renee Coffman, Harry Rosenberg, Ronald R. Fiscus. Resveratrol causes biphasic apoptotic and proliferative effects and at higher/proapoptotic/anti-angiogenesis concentrations causes suppression of nitric oxide/cGMP/protein kinase G signaling and decreased expression of prosurvival proteins c-IAP1, c-IAP2, livin and XIAP in human umbilical vein endothelial cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1008. doi:10.1158/1538-7445.AM2014-1008
Abstract 1010: Paradoxic effects of metformin on endothelial cells and angiogenesis
Authors: Bruno Antonino , Dallaglio Katiuscia , Cantelmo Anna Rita , Esposito Alessia I. , Ruggiero Luca , Orecchioni Stefania , Callieri Angelica , Bertolini Francesco , Pfeffer Ulrich , Noonan Douglas M. , Albini Adriana
Published: May 2015

Epidemiological evidence has suggested that metformin, an anti-hyperglycemic agent commonly used in the treatment of type 2 diabetes, is a potential cancer preventive agent. Anti-angiogenesis represents a key mechanism in cancer prevention, a concept termed angioprevention. Since conflicting data concerning the anti-angiogenic action of metformin are emerging, we elucidate the effects of metformin, on endothelial and tumor cells as well as on angiogenesis using in vitro, in vivo and transcriptomic approaches. We show that metformin inhibits endothelial cell ability to organize into capillary-like networks; this effect is partially dependent on the energy sensor AMPK. Gene expression and proteins profiling revealed paradoxic effects on several angiogenesis associated factors. We found induction of VEGF, COX2 and CXCR4 at the mRNA level and down-regulation of ADAMTS1. Interestingly, antibody array analysis showed essentially opposite regulation of numerous angiogenesis-associated proteins in endothelial and breast cancer cells.

We also show that endothelial production of cytochrome p450 family member CYP1B1 was up-regulated by tumor cell supernatants, while metformin blocked this effect by acting on AMPK. The metformin anti-angiogenic activity was exerted through inhibition of ERK1/2 activation, even in the presence of VEGF, while blocking AMPK activity abrogated this effect. Metformin inhibited angiogenesis induced by VEGF in matrigel pellets in vivo and contrasted the increase in microvessel density in obese mice on a high fat diet. Further, it down-regulated the number of endothelial precursor cells from white adipose tissue in obese mice. Our data show that metformin has an anti-angiogenic activity in vitro and in vivo, which is associated with a contradictory enhancement of chemokines and other inflammatory pro-angiogenic mediators, as well as a different regulation in endothelial and breast cancer cells.

Citation Format: Antonino Bruno, Katiuscia Dallaglio, Anna Rita Cantelmo, Alessia I. Esposito, Luca Ruggiero, Stefania Orecchioni, Angelica Callieri, Francesco Bertolini, Ulrich Pfeffer, Douglas M. Noonan, Adriana Albini. Paradoxic effects of metformin on endothelial cells and angiogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1010. doi:10.1158/1538-7445.AM2014-1010
Abstract 1017: Id-1 gene and protein as therapeutic target for head and neck squamous cell carcinoma
Authors: Murase Ryuichi , McAllister Sean , Fujita Yohei , Sumida Tomoki , Nakashiro Koichi , Desprez Pierre , Hamakawa Hiroyuki
Published: May 2015

Squamous cell carcinoma is one of the most common malignancies in head and neck region. Primary tumors, especially derived from undifferentiated cells, tend to have aggressive phenotypes, which are mainly characterized by local recurrence and distant metastasis. In this study we found that Id-1, a negative regulator of tissue specific transcription factors, is highly expressed in head and neck squamous carcinoma cells (HNSCC), and that the expression is correlated with the malignant phenotype, i.e., cell proliferation and invasion. Id-1 knockdown dramatically reduces squamous cell invasion that is accompanied by profound morphologic changes and robust reduction in expression levels of mesenchymal markers.In addition, reduction in tumor growth and neoangiogenesis were observed in vivo, indicating that knock-down of Id-1 drastically suppresses VEGFA expression. Our results also suggested that VEGFA-autocrine loop activates tylosine kinase pathways including Srk and FAK, and therefore manifests invasive phenotype. With clinical materials obtained from HNSCC patients, significant correlation was observed between Id-1 and VEGFA. Furthermore, we demonstrated that a non toxic compound, cannabidiol, significantly downregulates Id-1 gene expression and associated squamous cell proliferation and invasiveness. Taken together, these results suggest that Id-1 controls cancer cell phenotype in culture and in vivo, and that drugs targeting Id-1 represent a novel and promising strategy for improving the therapy and outcome of patients with HNSCC.

Citation Format: Ryuichi Murase, Sean McAllister, Yohei Fujita, Tomoki Sumida, Koichi Nakashiro, Pierre Desprez, Hiroyuki Hamakawa. Id-1 gene and protein as therapeutic target for head and neck squamous cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1017. doi:10.1158/1538-7445.AM2014-1017
Abstract 102: A longitudinal, orthotopic mouse imaging model using modified hNIS-A549 human lung adenocarcinoma cells and SPECT/CT imaging
Authors: McBride Amber Alane , Price Dominique Nicole , Norenberg Jeffrey P. , MacKenzie Debra A. , Thompson Todd Anthony , Muttil Pavan
Published: May 2015

The human sodium iodide symporter (hNIS; SLC5A5) is a membrane glycoprotein that is a transporter for iodide uptake and also concentrates the radiotracer technetium 99mTc-pertechnetate (99mTc). In this study, we investigated the use of hNIS as an imaging reporter gene expressed in lung cancer cells in nude mice that can be quantified using single-photon emission computed tomography (SPECT) imaging. The radionuclide 99mTc was selected for its rapid clearance from the body and its short physical half-life (i.e., 6 hours). These characteristics allowed for the development a highly sensitive spatial and temporal tumor-imaging model. Human lung adenocarcinoma A549 cells were genetically modified using plasmid and lentiviral vectors to stably express hNIS. Using these modified cells, we monitored xenograft and orthotopic tumor growth using SPECT/CT for a total of 47 days. hNIS expression was quantified using qPCR and tumor progression was monitored by SPECT voxel analysis and validated using H&E staining of pulmonary tumors. hNIS-lentiviral vector tumors exhibited significant 99mTc uptake over hNIS-plasmid vector cells and A549 unmodified control cells in vitro and in vivo. Furthermore, this mouse study achieved a 100% orthotopic tumor take rate. Thus, a highly sensitive preclinical imaging mouse lung cancer model was developed. This model can be imaged longitudinally, which is made possible through the stable incorporation of hNIS into the tumor cell, allowing for 99mTc uptake and SPECT/CT analysis of tumor burden. In future studies, we will investigate whether chemotherapeutic regimens can effectively reduce the growth of hNIS-expressing A549 tumors over time using this preclinical in vivo model. This novel lung cancer animal model could significantly reduce animal numbers, improve the quality of data by avoiding inter-animal variation, and allow for longitudinal analysis and efficacy of experimental chemotherapeutics.

Citation Format: Amber Alane McBride, Dominique Nicole Price, Jeffrey P. Norenberg, Debra A. MacKenzie, Todd Anthony Thompson, Pavan Muttil. A longitudinal, orthotopic mouse imaging model using modified hNIS-A549 human lung adenocarcinoma cells and SPECT/CT imaging. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 102. doi:10.1158/1538-7445.AM2014-102
Abstract 1039: Downregulation of beta1 integrins in E-cadherin positive triple negative breast cancer cells elicits pro-metastatic shift in migration strategy through TGFbeta/miR200/ZEB signaling network
Authors: Danen Erik H.
Published: May 2015

Interactions with the extracellular matrix (ECM) through integrin adhesion receptors provide cancer cells with physical and chemical cues that act in concert with growth factors to support survival and proliferation. Preclinical studies testing β1 integrin antagonists in (breast) cancer models have shown inhibition of tumor growth and sensitization to radio- or chemotherapy and these strategies are currently evaluated in clinical trials. Here, we show that downregulation of β1 integrins attenuates breast tumor growth but dissemination to the lungs from such small tumors can be markedly enhanced. β1 integrin downregulation induces compensatory upregulation of β3 integrins, but increased β3 expression does not lead to enhanced lung metastasis. Instead, β1 integrin downregulation in human and mouse triple negative, E-cadherin positive breast cancer cells elicits a switch from collective invasion to individual cell migration in 3D ECM. This involves alterations in the TGFβ-BMP signaling network shifting the balance between miR-200 and ZEB, which causes a block in E-cadherin transcription. The switch is fully reversible: restored β1 expression reinstates E-cadherin expression and cell cohesion. Moreover, restoring the network at the level of TGFβR, ZEB/miR-200 balance, or E-cadherin, restores cohesion and prevents the induction of lung metastasis without affecting tumor growth. These findings reveal that integrin-mediated ECM-attachments regulate a signaling network in control of epithelial characteristics that suppress metastatic spread. This raises concerns with respect to the use of β1 integrins as cancer drug targets.

Citation Format: Erik H. Danen. Downregulation of beta1 integrins in E-cadherin positive triple negative breast cancer cells elicits pro-metastatic shift in migration strategy through TGFbeta/miR200/ZEB signaling network. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1039. doi:10.1158/1538-7445.AM2014-1039
Abstract 1041: TGF-β1-induced EMT is suppressed by berberine in triple negative breast cancers
Authors: Lee Jeongmin
Published: May 2015

Elevated TGF-β secretion plays an important role in the development of cancer such as tumor metastasis, invasion, and the epithelial-to-mesenchymal transition (EMT). In addition, TGF-β-responsive gene signature is highly activated in chemotherapy-treated triple negative breast cancer (TNBC). Here, we investigated the effect of berberine (BBR) on TGF-β1-induced EMT in TNBC cells. Our results showed that TGF-β1 significantly increased the level of mesenchymal markers such as fibronectin, vimentin, and MMP-2 in Hs578T and BT549. To verify the effect of BBR on these phenomenons, we treated with BBR and then BBR decreased TGF-β1-induced mesenchymal markers in Hs578T and BT549 cells. Furthermore, we investigated the regulatory mechanism of TGF-β1-induced mesenchymal markers. TGF-β1-induced mesenchymal markers were prevented by a MEK1/2 inhibitor, U0126 or a Smad3 inhibitor, SIS3, respectively. Interestingly, BBR significantly decreased TGF-β1-induced the phosphorylation of ERK and Smad3 in Hs578T and BT549. Taken together, we demonstrated that BBR may act as a blocker in TGF-β1-induced EMT in TNBC.

Citation Format: Jeongmin Lee. TGF-β1-induced EMT is suppressed by berberine in triple negative breast cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1041. doi:10.1158/1538-7445.AM2014-1041
Abstract 1043: Distinctive roles of Smad3 C-tail and linker phosphorylation between cancer progression and suppression in TGF-beta1/Smad3 signal
Authors: Bae Eunjin , Ooshima Akira , Kim Seong-Jin
Published: May 2015

Transforming growth factor B1 (TGF-B) is the prototype of a large family of pleiotropic polypeptide cytokines that regulate a multitude of physiological functions. The ability of TGF-B1/Smad3 signal to inhibit proliferation of epithelial, neuronal and hematopoietic cells from which most human neoplasms originate suggests a role of TGF-B in tumor suppression. Smad3, a key transcription factor in TGF-B signaling, functions as both a positive and negative regulator in carcinogenesis. TGF-B induces phosphorylation of Smad3 C-terminal SXS motif in its canonical pathway as well as the serine/threonine residues in the linker region. The linker region has been known to contain multiple phosphorylation sites for proline-directed kinases such as CDK, c-Jun, p38 MAPK, Erk and GSK-3B. Here we present that the blockade of Smad3 C-terminal phosphorylation by adenoviral dominant-negative mutant promotes tumorigenesis, but markedly inhibits metastasis to the lung as induced by tail-vein injection and orthotopic transplant of human and mouse breast cancer cell lines. Conversely, mutation of Smad3 linker phosphorylation sites greatly suppresses tumorigenesis, while it enhances metastatic dissemination to the lung. In vitro study revealed that the Smad3 linker region is constitutively phosphorylated in the cancer cells, and that the mutation of Smad3 linker phosphorylation sites enhances the TGF-B1-induced EMT, growth arrest and apoptosis, suggesting that the canonical TGF-B1 signal mediated through C-tail phosphorylation is modulated by negative inputs from the linker phosphorylation. Furthermore, the blockade of linker phosphorylation reduces the stem cell population following suppression of mammosphere formation and downregulation of embryonic transcription factors including Oct4, NANOG and Sox-2, and induces apoptosis by repressing an antiapoptotic protein Bcl-2, suggesting that the Smad3 linker phosphorylation retains function for the maintenance of cancer stemness and survival. These results indicate that oncogenic and cancer-suppressive TGF-B1/Smad3 signals are regulated by the site-specific phosphorylation of Smad3 protein, imparting a new aspect to anti-cancer therapies that target the TGF-B signal pathway.

This work was supported by a National Research Foundation grant of Korea (2009-0081756) funded by the Korea government.

Citation Format: Eunjin Bae, Akira Ooshima, Seong-Jin Kim. Distinctive roles of Smad3 C-tail and linker phosphorylation between cancer progression and suppression in TGF-beta1/Smad3 signal. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1043. doi:10.1158/1538-7445.AM2014-1043
Abstract 1048: Dichotomy effects of Akt signaling in breast cancer
Authors: Lin Huey-Jen L. , Peng Zhengang
Published: May 2015

Background: The oncogenic roles contributed by the Akt/PKB kinase family remain controversial and presumably depend on cell context, but are perceived to be modulated by an interplay and net balance between various isoforms. This study is intended to decipher whether distinct Akt kinase isoforms exert either redundant or unique functions in regulating neoplastic features of breast cancer cells, including epithelial-mesenchymal transition (EMT), cell motility, and stem/progenitor cell expansion. Results: We demonstrate that overactivation of Akt signaling in nonmalignant MCF10A cells and in primary cultures of normal human mammary epithelial tissue results in previously unreported inhibitory effects on EMT, cell motility and stem/progenitor cell expansion. Importantly, this effect is largely redundant and independent of Akt isoform types. However, using a series of isogenic cell lines derived from MCF-10A cells but exhibiting varying stages of progressive tumorigenesis, we observe that this inhibition of neoplastic behavior can be reversed in epithelial cells that have advanced to a highly malignant state. In contrast to the tumor suppressive properties of Akt, activated Akt signaling in MCF10A cells can rescue cell viability upon treatment with cytotoxic agents. This feature is regarded as tumor-promoting. Conclusion: We demonstrate that Akt signaling conveys novel dichotomy effects in which its oncogenic properties contributes mainly to sustaining cell viability, as opposed to the its tumor suppressing effects, which are mediated by repressing EMT, cell motility, and stem/progenitor cell expansion. While the former exerts a tumor-enhancing effect, the latter merely acts as a safeguard by restraining epithelial cells at the primary sites until metastatic spread can be moved forward, a process that is presumably dictated by the permissive tumor microenvironment or additional oncogenic insults.

Citation Format: Huey-Jen L. Lin, Zhengang Peng. Dichotomy effects of Akt signaling in breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1048. doi:10.1158/1538-7445.AM2014-1048
Abstract 1053: Interplay of YB-1 and IL-6 in the acquisition of EMT-like characteristics
Authors: Castellana Barbara , Aasen Trond , Cajal Santiago Ramón y
Published: May 2015

An important step towards tumor progression and metastasis is the activation of the epithelial-mesenchymal transition (EMT) program. This complex process confers cancer cells traits such as enhanced motility, invasiveness and resistance to therapy. EMT can be triggered by the convergence of intrinsic factors and signals from the tumor microenvironment, such as aberrant expression of cytokines. Recently, the multifunctional oncoprotein YB-1 has been shown to play an important role in malignant tumors facilitating many of the “hallmarks of cancer” proposed by Hanahan and Weinberg. In this project we focused on the alliance between YB-1 and the cytokine IL-6, which has been implicated in tumor-cell metastasis and is a well known EMT inducer. Overexpression or direct addition of IL-6 up-regulates and activates YB-1 in the epithelial breast cancer cell line MCF7, leading to an upregulation of mesenchymal markers (Snail1, N-cadherin), increased cell migration and invasion, as well as morphological changes associated with an EMT-like phenotype. Conversely, in the mesenchymal-like breast cancer cell line MDA-MB-231, RNAi-mediated downregulation of YB-1 resulted in decreased IL-6 expression and an increase in epithelial-like cell characteristics.

Our results describe a novel interplay whereby IL-6 regulates YB-1 and vice versa creating a positive feed-forward loop driving EMT during breast cancer progression. In the future we aim to delineate the exact signalling pathways linking IL-6 and YB-1, and how they converge to orchestrate important processes such as growth, invasion and metastasis. The understanding of this interplay will set the stage for new combinatorial treatments of aggressive breast cancers.

Acronyms: EMT, epithelial to mesenchymal transition; YB-1, Ybox binding protein-1; IL-6 , Interleukin-6.

Citation Format: Barbara Castellana, Trond Aasen, Santiago Ramón y Cajal. Interplay of YB-1 and IL-6 in the acquisition of EMT-like characteristics. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1053. doi:10.1158/1538-7445.AM2014-1053
Abstract 1056: COX-2/PGE2-driven lung cancer invasion/metastasis is dependent on MIG-7 and phosphorylated prohibitin
Authors: Liang Chi-Ming , Ho Ming-Yi , Liang Shu-Mei
Published: May 2015

COX-2/prostaglandin E2 (PGE2) enhances lung cancer invasion/metastasis, but its mode of action is largely unclear. We showed here that PGE2 interacted with EP4 to increase phosphatidylinositol-(3,4,5)-triphosphate (PIP3), leading to increase in epithelial-mesenchymal transition and E-cadherin suppressors, notably Snail, ZEB1 and Twist. Prohibitin phosphorylated at threonine 258 (phospho-PHBT258) and MIG-7 played critical role in PGE2 effects respectively. Snail was regulated by phospho-PHBT258 via IKKα/β and Ras/Raf-1 signaling pathways, whereas ZEB1 and Twist, were regulated mainly by MIG-7 that also sustained PGE2 effects via positive feedback on phospho-AktS473. Downregulating phospho-PHBT258 and MIG-7 showed additive effect in attenuating lung cancer migration/invasion/metastasis and prolonging disease-free and overall survival of xenograft mice. Our findings highlight the potential for combination therapy targeting phospho-PHBT258 and MIG-7 to block the COX-2/PGE2 effects on cancer metastasis.

Citation Format: Chi-Ming Liang, Ming-Yi Ho, Shu-Mei Liang. COX-2/PGE2-driven lung cancer invasion/metastasis is dependent on MIG-7 and phosphorylated prohibitin. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1056. doi:10.1158/1538-7445.AM2014-1056
Abstract 1058: Grainyhead-like 2 regulates molecular subtype switching in epithelial ovarian cancer
Authors: Chung Vin Yee , Wong Meng Kang , Kuay Kuee Theng , Tan Tuan Zea , Guccione Ernesto , Thiery Jean Paul , Huang Ruby Yun-Ju
Published: May 2015

Epithelial ovarian cancer (EOC) is clinically heterogeneous, comprising different histological and biological subtypes. Despite tumor heterogeneity, patient stratification is lacking and targeted therapeutic options for EOC are limited. Epithelial-mesenchymal transition (EMT), an important developmental process that allows the conversion of epithelial cells to mesenchymal phenotype, has been implicated in contributing to the molecular heterogeneity in EOC. Emerging evidence suggests that EMT in EOC may be associated with tumor progression and metastasis. We aim to decipher the underlying EMT mechanisms by using a panel of 42 EMT-phenotyped EOC cell lines. We found that Grainyhead-like 2 (GRHL2), a transcription factor, was expressed exclusively in EOC cells with epithelial phenotype by using qPCR, ELISA and western blots. EOC tumors with Mesenchymal molecular subtype also showed a decrease in GRHL2 expression. These data suggest that GRHL2 is required for maintaining cell polarity or cell-cell adhesion. Therefore, manipulating the expression of GRHL2 might switch the EMT-related molecular subtypes in EOC. Here, we showed that knocking down of GRHL2 resulted in EMT changes in EOC cells with Epithelial molecular subtype, accompanied by an increase in cell motility and directional migration. GRHL2-deficient cells also showed a tendency to migrate individually instead of collectively, thus suggesting that GRHL2 might be required for collective cell migration. Knock-down of GRHL2 not only downregulates E-cadherin expression, but also interferes with the stability of E-cadherin at cell-cell junctions. Chromatin-immunoprecipitation sequencing (ChIP-seq) identified GRHL2 transcriptional targets that might be the downstream mediators for this molecular subtype switch. In conclusion, GRHL2 is an important regulator in maintaining the epithelial phenotype and crucial player in molecular heterogeneity in EOC.

Citation Format: Vin Yee Chung, Meng Kang Wong, Kuee Theng Kuay, Tuan Zea Tan, Ernesto Guccione, Jean Paul Thiery, Ruby Yun-Ju Huang. Grainyhead-like 2 regulates molecular subtype switching in epithelial ovarian cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1058. doi:10.1158/1538-7445.AM2014-1058
Abstract 1063: Inverse hormesis of cancer growth mediated by narrow ranges of tumor-directed antibodies
Authors: Pearce Oliver M.T. , Läubli Heinz , Verhagen Andrea , Secrest Patrick , Zhang Jiquan , Crocker Paul R. , Varki Nissi , Bui Jack , Varki Ajit
Published: May 2015

Compelling evidence for naturally occurring immunosurveillance against malignancies informs and justifies some current approaches towards cancer immunotherapy. However, some types of immune reactions have also been shown to facilitate tumor progression. For example, our previous studies showed that experimental tumor growth in mice can be enhanced by low levels of circulating antibodies directed against the non-human sialic acid N-glycolyl-neuraminic acid (Neu5Gc, which accumulates in human tumors from dietary sources). However, tumor growth could instead be inhibited by anti-Neu5Gc antibodies from a different source, in a different model. Thus, anti-Neu5Gc antibodies appeared to be showing differential effects on tumor growth. However it remains generally unclear whether the immune responses that mediate cancer immunosurveillance versus those responsible for inflammatory facilitation are qualitatively and/or quantitatively distinct. Here, we address this question using multiple murine tumor growth models in which polyclonal antibodies against tumor antigens such as Neu5Gc can alter tumor progression. We found that while growth was stimulated at low antibody doses it was inhibited by high doses, over a linear and remarkably narrow range, defining an immune response curve (IRC), i.e., inverse hormesis. Moreover, modulation of immune responses against the tumor by altering antibody avidity or by enhancing innate immunity shifted the IRC in the appropriate direction. Thus, the dualistic role of immunosurveillance versus inflammation in modulating tumor progression can be quantitatively distinguished in multiple model systems, and can occur over a remarkably narrow range. We also reproduced the biphasic IRC in a model using the monoclonal anti-CD20 antibody rituximab. Furthermore, depletion of macrophages abrogated the growth promotion at low antibody concentrations and depletion of NK cells reduced growth inhibition at high antibody concentrations. These findings may have implications for the etiology and prevention of cancer, and for immunotherapeutic approaches utilizing antibodies.

Citation Format: Oliver M.T. Pearce, Heinz Läubli, Andrea Verhagen, Patrick Secrest, Jiquan Zhang, Paul R. Crocker, Nissi Varki, Jack Bui, Ajit Varki. Inverse hormesis of cancer growth mediated by narrow ranges of tumor-directed antibodies. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1063. doi:10.1158/1538-7445.AM2014-1063