bluuebunny/crossref_metadata_2025 huggingface dataset:
THE IMPERATIVE OF INTEGRATED MINERAL AND OIL RESOURCES EXTRACTION AND MANAGEMENT POLICY FOR SUSTAINABLE PEACE AND DEVELOPMENT IN NIGERIA
Authors: MARCELLUS IKEANYIBE OKEY
Published: May 2010

Organised mining and extraction of mineral resources began in 1903 in the Northern Protectorates and in 1904 in the Southern Protectorates of modern Nigeria with the establishment of Mineral Survey of the Northern Protectorates and the Mineral Survey of Southern Protectorates respectively, by the British colonial government. Over a century later, extraction of mineral resources in the country is still highly underdeveloped. There are great conflicts that surround oil extraction in the Niger Delta region, and Nigeria imports solid minerals which she is capable of producing domestically. The extraction of solid minerals and oil resources also calls into question issues of environmental neglect in the country. This paper provides for a descriptive analysis of Nigeria's mineral and oil resources extraction and management policy since the colonial period. It is observed that public policies in the sector have been interventionist, marginal, disjointed and elitist, and, have not properly included issues of sustainability for peace and development. Key recommendations of the paper are that public policy in the mineral and oil sector should seek to include more stringent regulations in relation to the environment, ensure equity in rent or royalty distribution especially to the host communities and develop the extraction of solid minerals with which the country is abundantly blessed.
THE INEQUALITY OF NATURAL RESOURCES CONSUMPTION AND ITS RELATIONSHIP WITH THE SOCIAL DEVELOPMENT LEVEL BASED ON THE ECOLOGICAL FOOTPRINT AND THE HDI
Authors: CHEN DONGJING , MA XIAOYAN , MU HAIRONG , LI PEIYING
Published: May 2010

This paper aims to provide a better understanding of the current situation of natural resources consumption in the world and its relationship with the level of social development. The Ecological Footprint concept is used to indicate human beings' environmental impact, and the Human Development Index (HDI) is used as a process for the social development level. Based on the dataset of 136 countries from the World Wildlife Fund (WWF), we calculate the Gini coefficients of the total Ecological Footprint per person (EF) and its sub items, i.e., Renewable Resources Footprint per person (REF) and Energy Footprint per person (EEF). The results indicate that significant inequality exists in natural resources consumption among the 136 countries from 1996 to 2005, and inequality of the EEF is the largest. We also calculate the Lorenz asymmetry coefficients of EF, REF and EEF, which are all greater than 1, indicating that the inequality results from some countries having extremely high resources consumption. The regression analyses of EF, REF and EEF with HDI, respectively, are made to show that there is a significant U-shaped relationship between natural resources consumption per person and the social development level rather than an inverted U-shaped relationship. Therefore, the Environmental Kuznets Curve (EKC) hypothesis is not supported by this research.
Theoretical Perspectives on Protein Folding
Authors: Thirumalai D. , O'Brien Edward P. , Morrison Greg , Hyeon Changbong
Published: May 2010

Understanding how monomeric proteins fold under in vitro conditions is crucial to describing their functions in the cellular context. Significant advances in theory and experiments have resulted in a conceptual framework for describing the folding mechanisms of globular proteins. The sizes of proteins in the denatured and folded states, cooperativity of the folding transition, dispersions in the melting temperatures at the residue level, and timescales of folding are, to a large extent, determined by N, the number of residues. The intricate details of folding as a function of denaturant concentration can be predicted by using a novel coarse-grained molecular transfer model. By watching one molecule fold at a time, using single-molecule methods, investigators have established the validity of the theoretically anticipated heterogeneity in the folding routes and the N-dependent timescales for the three stages in the approach to the native state. Despite the successes of theory, of which only a few examples are documented here, we conclude that much remains to be done to solve the protein folding problem in the broadest sense.
Structure and Activation of the Visual Pigment Rhodopsin
Authors: Smith Steven O.
Published: May 2010

Rhodopsin is a specialized G protein–coupled receptor (GPCR) found in vertebrate rod cells. Absorption of light by its 11-cis retinal chromophore leads to rapid photochemical isomerization and receptor activation. Recent results from protein crystallography and NMR spectroscopy show how structural changes on the extracellular side of rhodopsin induced by retinal isomerization are coupled to the motion of membrane-spanning helices to create a G protein binding pocket on the intracellular side of the receptor. The signaling pathway provides a comprehensive explanation for the conservation of specific amino acids and structural motifs across the class A family of GPCRs, as well as for the conservation of selected residues within the visual receptor subfamily. The emerging model of activation indicates that, rather than being unique, the visual receptors provide a basis for understanding the common structural and dynamic elements in the class A GPCRs.
Rewiring Cells: Synthetic Biology as a Tool to Interrogate the Organizational Principles of Living Systems
Authors: Bashor Caleb J. , Horwitz Andrew A. , Peisajovich Sergio G. , Lim Wendell A.
Published: May 2010

The living cell is an incredibly complex entity, and the goal of predictively and quantitatively understanding its function is one of the next great challenges in biology. Much of what we know about the cell concerns its constituent parts, but to a great extent we have yet to decode how these parts are organized to yield complex physiological function. Classically, we have learned about the organization of cellular networks by disrupting them through genetic or chemical means. The emerging discipline of synthetic biology offers an additional, powerful approach to study systems. By rearranging the parts that comprise existing networks, we can gain valuable insight into the hierarchical logic of the networks and identify the modular building blocks that evolution uses to generate innovative function. In addition, by building minimal toy networks, one can systematically explore the relationship between network structure and function. Here, we outline recent work that uses synthetic biology approaches to investigate the organization and function of cellular networks, and describe a vision for a synthetic biology toolkit that could be used to interrogate the design principles of diverse systems.
Adventures in Physical Chemistry
Authors: McConnell Harden
Published: May 2010

My research has included chemical physics, electron and NMR spectroscopy, membrane biophysics, and immunology. This research was curiosity driven as well as problem and technique oriented. A theoretical equation was developed for relating nuclear hyperfine splittings to electron spin distributions in free radicals. Another equation was developed to relate NMR spectra to chemical reaction rates. Early evidence for the liquid-like properties of cell membranes was obtained through the use of paramagnetic probes (spin labels). Spin labels were used in measurements of lateral as well as transverse diffusion of phospholipids in bilayer membranes. Liquid-liquid phase separations were discovered in monolayer membranes containing phospholipids and cholesterol. In the area of immunology, it was shown that antigenic peptides bind to reconstituted class II MHC molecules in membranes and trigger specific T-helper cells.
Compact Intermediates in RNA Folding
Authors: Woodson Sarah A.
Published: May 2010

Large noncoding RNAs fold into their biologically functional structures via compact yet disordered intermediates, which couple the stable secondary structure of the RNA with the emerging tertiary fold. The specificity of the collapse transition, which coincides with the assembly of helical domains, depends on RNA sequence and counterions. It determines the specificity of the folding pathways and the magnitude of the free energy barriers to the ensuing search for the native conformation. By coupling helix assembly with nascent tertiary interactions, compact folding intermediates in RNA also play a crucial role in ligand binding and RNA-protein recognition.
Bacterial Microcompartment Organelles: Protein Shell Structure and Evolution
Authors: Yeates Todd O. , Crowley Christopher S. , Tanaka Shiho
Published: May 2010

Some bacteria contain organelles or microcompartments consisting of a large virion-like protein shell encapsulating sequentially acting enzymes. These organized microcompartments serve to enhance or protect key metabolic pathways inside the cell. The variety of bacterial microcompartments provide diverse metabolic functions, ranging from CO2fixation to the degradation of small organic molecules. Yet they share an evolutionarily related shell, which is defined by a conserved protein domain that is widely distributed across the bacterial kingdom. Structural studies on a number of these bacterial microcompartment shell proteins are illuminating the architecture of the shell and highlighting its critical role in controlling molecular transport into and out of microcompartments. Current structural, evolutionary, and mechanistic ideas are discussed, along with genomic studies for exploring the function and diversity of this family of bacterial organelles.
Ribosome Structure and Dynamics During Translocation and Termination
Authors: Dunkle Jack A. , Cate Jamie H.D.
Published: May 2010

Protein biosynthesis, or translation, occurs on the ribosome, a large RNA-protein assembly universally conserved in all forms of life. Over the last decade, structures of the small and large ribosomal subunits and of the intact ribosome have begun to reveal the molecular details of how the ribosome works. Both cryo-electron microscopy and X-ray crystallography continue to provide fresh insights into the mechanism of translation. In this review, we describe the most recent structural models of the bacterial ribosome that shed light on the movement of messenger RNA and transfer RNA on the ribosome after each peptide bond is formed, a process termed translocation. We also discuss recent structures that reveal the molecular basis for stop codon recognition during translation termination. Finally, we review recent advances in understanding how bacteria handle errors in both translocation and termination.
Effect of intercalated cell-specific Rh C glycoprotein deletion on basal and metabolic acidosis-stimulated renal ammonia excretion
Authors: Lee Hyun-Wook , Verlander Jill W. , Bishop Jesse M. , Nelson Raoul D. , Handlogten Mary E. , Weiner I. David
Published: May 2010

Rh C glycoprotein (Rhcg) is an NH3-specific transporter expressed in both intercalated cells (IC) and principal cells (PC) in the renal collecting duct. Recent studies show that deletion of Rhcg from both intercalated and principal cells inhibits both basal and acidosis-stimulated renal ammonia excretion. The purpose of the current studies was to better understand the specific role of Rhcg expression in intercalated cells in basal and metabolic acidosis-stimulated renal ammonia excretion. We generated mice with intercalated cell-specific Rhcg deletion (IC-Rhcg-KO) using Cre-loxP techniques; control (C) mice were floxed Rhcg but Cre negative. Under basal conditions, IC-Rhcg-KO and C mice excreted urine with similar ammonia content and pH. Mice were then acid loaded by adding HCl to their diet. Ammonia excretion after acid loading increased similarly in IC-Rhcg-KO and C mice during the first 2 days of acid loading but on day 3 was significantly less in IC-Rhcg-KO than in C mice. During the first 2 days of acid loading, urine was significantly more acidic in IC-Rhcg-KO mice than in C mice; there was no difference on day 3. In IC-Rhcg-KO mice, acid loading increased principal cell Rhcg expression in both the cortex and outer medulla as well as expression of another ammonia transporter, Rh glycoprotein B (Rhbg), in principal cells in the outer medulla. We conclude that 1) Rhcg expression in intercalated cells is necessary for the normal renal response to metabolic acidosis; 2) principal cell Rhcg contributes to both basal and acidosis-stimulated ammonia excretion; and 3) adaptations in Rhbg expression occur in response to acid-loading.
Differential Control of Spontaneous and Evoked GABA Release by Presynaptic L-Type Ca2+ Channels in the Rat Medial Preoptic Nucleus
Authors: Malinina Evgenya , Druzin Michael , Johansson Staffan
Published: May 2010

To clarify the role of presynaptic L-type Ca2+ channels in GABA-mediated transmission in the medial preoptic nucleus (MPN), spontaneous, miniature, and impulse-evoked inhibitory postsynaptic currents (sIPSCs, mIPSCs, and eIPSCs, respectively) were recorded from MPN neurons in a slice preparation from rat brain. The effects of different stimulus protocols and pharmacological tools to detect contributions of L-type Ca2+ channels and of Ca2+-activated K+ (KCa) channels were analyzed. Block of L-type channels did not affect the sIPSC and mIPSC properties (frequency, amplitude, decay time course) in the absence of external stimulation but unexpectedly potentiated the eIPSCs evoked at low stimulus frequency (0.1–2.0 Hz). This effect was similar to and overlapping with the effect of KCa-channel blockers. High-frequency stimulation (50 Hz for 10 s) induced a substantial posttetanic potentiation (PTP) of the eIPSC amplitude and of the sIPSC frequency. Block of L-type channels still potentiated the eIPSC during PTP, but in contrast, reduced the sIPSC frequency during PTP. It was concluded that L-type channels provide a means for differential control of spontaneous and impulse-evoked GABA release and that this differential control is prominent during short-term synaptic plasticity. Functional coupling of the presynaptic L-type channels to KCa channels explains the observed effects on eIPSCs.
Generalization of Dynamics Learning Across Changes in Movement Amplitude
Authors: Mattar Andrew A. G. , Ostry David J.
Published: May 2010

Studies on generalization show the nature of how learning is encoded in the brain. Previous studies have shown rather limited generalization of dynamics learning across changes in movement direction, a finding that is consistent with the idea that learning is primarily local. In contrast, studies show a broader pattern of generalization across changes in movement amplitude, suggesting a more general form of learning. To understand this difference, we performed an experiment in which subjects held a robotic manipulandum and made movements to targets along the body midline. Subjects were trained in a velocity-dependent force field while moving to a 15 cm target. After training, subjects were tested for generalization using movements to a 30 cm target. We used force channels in conjunction with movements to the 30 cm target to assess the extent of generalization. Force channels restricted lateral movements and allowed us to measure force production during generalization. We compared actual lateral forces to the forces expected if dynamics learning generalized fully. We found that, during the test for generalization, subjects produced reliably less force than expected. Force production was appropriate for the portion of the transfer movement in which velocities corresponded to those experienced with the 15 cm target. Subjects failed to produce the expected forces when velocities exceeded those experienced in the training task. This suggests that dynamics learning generalizes little beyond the range of one's experience. Consistent with this result, subjects who trained on the 30 cm target showed full generalization to the 15 cm target. We performed two additional experiments that show that interleaved trials to the 30 cm target during training on the 15 cm target can resolve the difference between the current results and those reported previously.
Using of H‐Infinity Control Method in Attitude Control System of Rigid‐Flexible Satellite
Authors: Méndez Cubillos Ximena Celia , de Souza Luiz Carlos Gadelha
Published: May 2010

The attitude control systems of satellites with rigid and flexible components are demanding more and more better performance resulting in the development of several methods control. For that reason, control design methods presently available, including parameters and states estimation, robust and adaptive control, as well as linear and nonlinear theory, need more investigation to know their capability and limitations. In this paper the investigated technique is H‐Infinity method in the performance of the Attitude Control System of a Rigid‐Flexible Satellite.
Discriminant Analysis ofUndaria pinnatifidaProduction Areas Using Trace Elemental Analysis
Authors: Kaihara Mikio
Published: May 2010

Increasingly, attention is being paid to declaring the origin of agricultural and marine products after the advent of the bovine spongiform encephalopathy (BSE; commonly known as mad-cow disease). The display of the production centers onU. pinnatifidahas been required in Japan since 2006. As an example of testing in another marine product, near-infrared spectra (NIR) and trace elemental analysis ofU. pinnatifidaare proven effective methods for discriminating production centers by us and Food and Agricultural Materials Inspection Center (FAMIC). In the present study, we found that X-ray fluorescence analysis of Br was also effective for the discrimination of production centers. The results of our study suggest that a combination of NIR and X-ray fluorescence analysis is a convenient and efficient method for determination due simple sampling procedures and increased effectiveness.
Electrospun Poly(L‐Lactide‐co‐ε‐Caprolactone)/Polyethylene Oxide/Hydroxyapaite Nanofibrous Membrane for Guided Bone Regeneration
Authors: Wang Gang , Ren Tianbin , Cao Chunhong , Yuan Weizhong , Song Ying , Su Jiansheng
Published: May 2010

A series of poly(L‐lactide‐co‐ε‐caprolactone)/polyethylene oxide/hydroxyapaite (PLCL/PEO/HA) composite fibrous membranes were prepared by elecrospinning technology for guided bone regeneration. The morphology, water permeability and mechanical properties of the membranes were investigated. The HA nanocrystals can be well distributed in the PLCL/PEO matrix. And the diameter of composite nanofiber is larger than that of pure PLCL. The fibers with uniform size and large diameter were obtained when the contents of PEO and HA were 0.4% and 0.03%, respectively. In this condition, the obtained membrane presents the best water permeability. Furthermore, the nanofibrous membrane with largest tensile strength was obtained when the contents of PEO and HA were 0.5% and 0.03%, respectively.
Blind Deconvolution for Jump‐Preserving Curve Estimation
Authors: Huang Xingfang , Qiu Peihua
Published: May 2010

In many applications, observed signals are contaminated by both random noise and blur. This paper proposes a blind deconvolution procedure for estimating a regression function with possible jumps preserved, by removing both noise and blur
when recovering the signals. Our procedure is based on three local linear kernel estimates of the regression function, constructed from observations in a left‐side, a right‐side, and a two‐side neighborhood of a given point, respectively. The estimated function at the given point is then defined by one of the three estimates with the smallest weighted residual sum of squares. To better remove the noise and blur, this estimate can also be updated iteratively. Performance of this procedure is investigated by both simulation and real data examples, from which it can be seen that our procedure performs well in various cases.
Direct Evidence of Reduction of Cloud Water after Spreading Diatomite Particles in Stratus Clouds in Beijing, China
Authors: Zhang Qiang , Huang Mengyu , Tie Xuexi , Ma Xincheng
Published: May 2010

Artificial weather modification experiments have been intensively practiced in many years over China, and some progresses have been made, including more methodologies and advanced instruments. However, a challenge question still remains for providing convincing scientific evidence during these practices and experiments. This is a very difficult scientific issue, which is related to complicated cloud physical science, such as to accurately predict the large natural variability of cloud formation and precipitation. In this study, we report a clear evidence that the cloud water is reduced after spreading diatomite particles in stratus clouds during a field experiment in Beijing, China. The analysis shows that the diatomite particles (15–20 μm in radius) are large and have strong hygroscopic property (absorbing cloud water). As a result, during the experiment, spreading large diatomite particles lead to downward motion (producing more stable atmospheric condition) and reduction of cloud water. It is noted that due to lacks of instruments, this designed experiment only can provide a qualitative result (such as photo evidence), and no quantitative result can be drawn from this experiment.
Malignant Progression in Two Children with Multiple Osteochondromas
Authors: Schmale Gregory A. , Hawkins Douglas S. , Rutledge Joe , Conrad Ernest U.
Published: May 2010

Multiple Osteochondromas (MO) is a disease of benign bony growths with a low incidence of malignant transformation. Secondary chondrosarcoma in children is rare even in children with MO. Making a diagnosis of malignancy in low-grade cartilage tumors is challenging and requires consideration of clinical, radiographic, and histopathological factors. We report two cases of skeletally immature patients with MO who presented with rapidly enlarging and radiographically aggressive lesions consistent with malignant transformation. Both underwent allograft reconstruction of the involved site with no signs of recurrence or metastatic disease at a minimum of four-year follow-up.
Impaired Skeletal Muscle Repair after Ischemia-Reperfusion Injury in Mice
Authors: Vignaud A. , Hourde C. , Medja F. , Agbulut O. , Butler-Browne G. , Ferry A.
Published: May 2010

Ischemia/reperfusion (IR) injury can induce skeletal muscle fibre death and subsequent regeneration. By 14 days, absolute and specific maximal forces and fatigue resistance in ischemic/reperfused soleus muscles were still reduced (−89%, −81%, and −75%, resp.) as compared to control muscles (P<.05). The decrease of these parameters in ischemic/reperfused muscle was much greater than that of myotoxic injured muscles (−12%, −11%, and −19%;P<.05). In addition, at 14 days ischemic/reperfused muscle structure was still abnormal, showing small muscle fibres expressing neonatal myosin heavy chain and large necrotic muscle fibres that were not observed in myotoxin treated muscles. By 56 days, in contrast to myotoxin treated muscles, specific maximal force and muscle weight of the ischemic/reperfused muscles did not fully recover (P<.05). This differential recovery between ischemic/reperfused and myotoxin treated muscles was not related to the differences in the initial cell death, loss of satellite cells after injury, expression of growth factors (IGF1, IGF2..), or capillary density in regenerating muscles. In conclusion, our results demonstrate that IR injury in mice induces long term detrimental effects in skeletal muscles and that the recovery following IR injury was delayed for yet unknown reasons as compared to myotoxic injury.
Optical Redox Ratio Differentiates Breast Cancer Cell Lines Based on Estrogen Receptor Status
Authors: Ostrander Julie Hanson , McMahon Christine M. , Lem Siya , Millon Stacy R. , Brown J. Quincy , Seewaldt Victoria L. , Ramanujam Nimmi
Published: May 2010

Autofluorescence spectroscopy is a powerful imaging technique that exploits endogenous fluorophores. The endogenous fluorophores NADH and flavin adenine dinucleotide (FAD) are two of the principal electron donors and acceptors in cellular metabolism, respectively. The optical oxidation-reduction (redox) ratio is a measure of cellular metabolism and can be determined by the ratio of NADH/FAD. We hypothesized that there would be a significant difference in the optical redox ratio of normal mammary epithelial cells compared with breast tumor cell lines and that estrogen receptor (ER)–positive cells would have a higher redox ratio than ER-negative cells. To test our hypothesis, the optical redox ratio was determined by collecting the fluorescence emission for NADH and FAD via confocal microscopy. We observed a statistically significant increase in the optical redox ratio of cancer compared with normal cell lines (P < 0.05). Additionally, we observed a statistically significant increase in the optical redox ratio of ER(+) breast cancer cell lines. The level of ESR1 expression, determined by real-time PCR, directly correlated with the optical redox ratio (Pearson's correlation coefficient = 0.8122, P = 0.0024). Furthermore, treatment with tamoxifen and ICI 182,870 statistically decreased the optical redox ratio of only ER(+) breast cancer cell lines. The results of this study raise the important possibility that fluorescence spectroscopy can be used to identify subtypes of breast cancer based on receptor status, monitor response to therapy, or potentially predict response to therapy. This source of optical contrast could be a potentially useful tool for drug screening in preclinical models. Cancer Res; 70(11); 4759–66. ©2010 AACR.
CD117 and Stro-1 Identify Osteosarcoma Tumor-Initiating Cells Associated with Metastasis and Drug Resistance
Authors: Adhikari Amit S. , Agarwal Neeraj , Wood Byron M. , Porretta Constance , Ruiz Bernardo , Pochampally Radhika R. , Iwakuma Tomoo
Published: May 2010

Emerging evidence indicates the presence of tumor-initiating cells (TIC) or cancer stem cells in osteosarcoma. However, no study has shown specific markers to identify osteosarcoma TICs with in vivo tumor formation ability. Additionally, there has been a lack of investigations gauging the contribution of osteosarcoma TICs to metastatic and drug-resistant properties. In this study, we have identified mouse and human osteosarcoma TICs using mesenchymal stem cell markers CD117 and Stro-1. These markers were preferentially expressed in spheres and doxorubicin-resistant cells. Both mouse and human cells expressing these markers were sorted and analyzed for their abilities of tumor formation with as few as 200 cells, self-renewability, multipotency, drug resistance, metastatic potential, and enrichment of a metastasis-associated marker (CXCR4) and a drug resistance marker (ABCG2). CD117+Stro-1+ cells efficiently formed serially transplantable tumors, whereas CD117−Stro-1− cells rarely initiated tumors. On orthotopic injections, CD117+Stro-1+ cell-derived tumors metastasized at a high frequency. Further, CD117+Stro-1+ cells showed high invasive and drug-resistant properties and were efficiently enriched for CXCR4 (20–90%) and ABCG2 (60–90%). These results suggest possible mechanisms for the high metastatic and drug-resistant properties of osteosarcoma TICs. In summary, CD117 and Stro-1 identify osteosarcoma TICs associated with the most lethal characteristics of the disease—metastasis and drug resistance—and these markers offer candidates for TIC-targeted drug delivery aimed at eradicating osteosarcoma. Cancer Res; 70(11); 4602–12. ©2010 AACR.
E2F3a Is Critically Involved in Epidermal Growth Factor Receptor–Directed Proliferation in Ovarian Cancer
Authors: Reimer Daniel , Hubalek Michael , Riedle Svenja , Skvortsov Sergej , Erdel Martin , Concin Nicole , Fiegl Heidi , Müller-Holzner Elisabeth , Marth Christian , Illmensee Karl , Altevogt Peter , Zeimet Alain G.
Published: May 2010

We describe for the first time a new integral molecular pathway, linking transcription factor E2F3a to epidermal growth factor receptor (EGFR) activation in ovarian cancer cells. Investigations on the role of E2F family members in EGFR-mediated mitogenic signaling revealed that E2F3a was selectively upregulated following EGFR activation, whereas all other E2F family members remained unaffected. In contrast, EGF treatment of healthy ovarian surface epithelial and mesothelial cells yielded a selective upregulation of proliferation-promoting E2F1 and E2F2 without influencing E2F3a expression. In ovarian cancer cell lines, the extent of EGF-induced proliferative stimulus was closely related to the magnitude of E2F3a increase, and proliferation inhibition by E2F3a knockdown was not overcome by EGF exposure. Furthermore, the EGFR-E2F3a axis was found to be signal transducer and activator of transcription 1/3 dependent and the ratio of IFN-regulatory factor (IRF)-1 to IRF-2 was shown to be determinative for E2F3a control. In a pilot study on 32 primary ovarian cancer specimens, a highly significant correlation between activated EGFR and E2F3a expression was disclosed. This new integral pathway in the EGFR-driven mitogenic cell response, which through its key player E2F3a was found to be essential in triggering proliferation in ovarian cancer cells, provides new insights into EGFR signaling and could represent the basis for appealing new therapeutic approaches in ovarian cancer. Cancer Res; 70(11); 4613–23. ©2010 AACR.
AML1/ETO Proteins Control POU4F1/BRN3A Expression and Function in t(8;21) Acute Myeloid Leukemia
Authors: Dunne Jenny , Gascoyne Duncan M. , Lister T. Andrew , Brady Hugh J.M. , Heidenreich Olaf , Young Bryan D.
Published: May 2010

A variety of genetic lesions, including chromosomal translocations, internal tandem duplications, and mutations, have been described in acute myeloid leukemia (AML). Expression profiling has shown that chromosomal translocations, in particular, are associated with distinctive patterns of gene expression. AML exhibiting the translocation t(8;21), which fuses the AML1 and ETO genes, has such a characteristic expression profile. One gene whose expression is highly correlated with the presence of the AML1/ETO fusion is POU4F1, which encodes the POU homeodomain transcription factor BRN3A. Here we show using specific siRNA in t(8;21) cells and overexpression studies in progenitor cells that AML1/ETO promotes expression of POU4F1/BRN3A. This effect requires DNA-binding function of AML1/ETO, and accordingly, AML1/ETO is bound to the POU4F1 locus in t(8;21) cells. Functionally, whereas overexpression of Brn3a in murine hematopoietic progenitor cells induces terminal myeloid differentiation, coexpression of AML1/ETO or AML1/ETO9a blocks this effect. Furthermore, Brn3a reduction by shRNA impairs AML1/ETO-induced immortalization of murine progenitors. In summary, we identify POU4F1/BRN3A as a novel potential upregulated AML1/ETO target gene whose dramatically high expression may cooperate with AML1/ETO in t(8;21) cells. Cancer Res; 70(10); 3985–95. ©2010 AACR.
A Novel Senescence-Evasion Mechanism Involving Grap2 and Cyclin D Interacting Protein Inactivation by Ras Associated with Diabetes in Cancer Cells under Doxorubicin Treatment
Authors: Lee Inkyoung , Yeom Seon-Yong , Lee Sook-Ja , Kang Won Ki , Park Chaehwa
Published: May 2010

Ras associated with diabetes (Rad) is a Ras-related GTPase that promotes cell growth by accelerating cell cycle transitions. Rad knockdown induced cell cycle arrest and premature senescence without additional cellular stress in multiple cancer cell lines, indicating that Rad expression might be critical for the cell cycle in these cells. To investigate the precise function of Rad in this process, we used human Rad as bait in a yeast two-hybrid screening system and sought Rad-interacting proteins. We identified the Grap2 and cyclin D interacting protein (GCIP)/DIP1/CCNDBP1/HHM, a cell cycle–inhibitory molecule, as a binding partner of Rad. Further analyses revealed that Rad binds directly to GCIP in vitro and coimmunoprecipitates with GCIP from cell lysates. Rad translocates GCIP from the nucleus to the cytoplasm, thereby inhibiting the tumor suppressor activity of GCIP, which occurs in the nucleus. Furthermore, in the presence of Rad, GCIP loses its ability to reduce retinoblastoma phosphorylation and inhibit cyclin D1 activity. The function of Rad in transformation is also evidenced by increased telomerase activity and colony formation according to Rad expression level. In vivo tumorigenesis analyses revealed that tumors derived from Rad knockdown cells were significantly smaller than those from control cells (P = 0.0131) and the preestablished tumors are reduced in size after the injection of siRad (P = 0.0064). Therefore, we propose for the first time that Rad may promote carcinogenesis at least in part by inhibiting GCIP-mediated tumor suppression. Cancer Res; 70(11); 4357–65. ©2010 AACR.
Targeting Fibroblast Growth Factor Receptors Blocks PI3K/AKT Signaling, Induces Apoptosis, and Impairs Mammary Tumor Outgrowth and Metastasis
Authors: Dey Julien H. , Bianchi Fabrizio , Voshol Johannes , Bonenfant Debora , Oakeley Edward J. , Hynes Nancy E.
Published: May 2010

Members of the fibroblast growth factor receptor (FGFR) family have essential roles in normal physiology and in cancer where they control diverse processes. FGFRs have been associated with breast cancer development. Thus, models to study the role of FGFR in breast cancer and their targeting potential are important. We present an in vitro and in vivo analysis of FGFRs in the breast cancer model cell lines 67NR and 4T1. We show that both tumor cell lines coexpress FGFRs and ligands and display autocrine FGFR signaling activity. Fibroblast growth factor receptor substrate 2 (FRS2), a downstream mediator of FGFR, is constitutively tyrosine phosphorylated and multiple signaling pathways are active. Treatment of 67NR and 4T1 cultures with TKI258, an FGFR tyrosine kinase inhibitor (TKI), caused a rapid decrease in FRS2 phosphorylation; decreased the activity of extracellular signal–regulated kinase 1/2 (ERK1/2), AKT, and phospholipase Cγ; and blocked proliferation of both tumor lines. Furthermore, TKI258 induced 4T1 apoptotic cell death via blockade of the phosphoinositide 3-kinase/AKT pathway. In vivo, one dose of TKI258 rapidly lowered FRS2 phosphorylation and ERK1/2 and AKT activity in mammary tumors. Long-term TKI258 treatment of 4T1 tumor– and 67NR tumor–bearing mice had a significant effect on primary tumor outgrowth and 4T1 tumor–induced lung metastases. A microarray analysis was carried out to identify targets with roles in TKI258 antitumor activity and potential prognostic markers in human breast tumors. Of interest are the downregulated matrix metalloproteases (MMP), in particular MMP9, which is essential for metastatic spread of 4T1 tumors. Cancer Res; 70(10); 4151–62. ©2010 AACR.
A Functional Receptor for B-Cell–Activating Factor Is Expressed on Human Acute Lymphoblastic Leukemias
Authors: Parameswaran Reshmi , Müschen Markus , Kim Yong-mi , Groffen John , Heisterkamp Nora
Published: May 2010

B-lineage acute lymphoblastic leukemia (ALL) arises by transformation of a progenitor (pre-B) cell. Cure rates in adults remain low and treatment is complicated by support provided by the microenvironment to the leukemic cells, indicating an urgent need to better understand the factors that promote their survival. B-cell–activating factor (BAFF) and its receptor BAFF-R are important for survival and growth of mature normal and malignant B cells but are not expressed on pre-B cells. Unexpectedly, all cells in the primary Philadelphia chromosome (Ph)–positive and Ph-negative ALL samples tested were positive for high BAFF-R cell surface expression. BAFF-R was fully competent to bind BAFF, and stimulation of the receptor activated both the classic and the noncanonical NF-κB pathways. Recombinant BAFF supported survival of the ALL cells in the absence of stroma, and it significantly attenuated the rate of apoptosis caused by exposure to nilotinib, a drug used therapeutically to treat Ph-positive ALLs. Surprisingly, BAFF mRNA and protein were also expressed in the same cells but BAFF was not shed into the medium. Our report is the first showing universal expression of BAFF-R by pre-B ALL cells and opens the possibility of blocking its function as an adjuvant therapeutic strategy. Cancer Res; 70(11); 4346–56. ©2010 AACR.
Activation of β-Catenin by Hypoxia in Hepatocellular Carcinoma Contributes to Enhanced Metastatic Potential and Poor Prognosis
Authors: Liu Liang , Zhu Xiao-Dong , Wang Wen-Quan , Shen Yuan , Qin Yi , Ren Zheng-Gang , Sun Hui-Chuan , Tang Zhao-You
Published: May 2010

Purpose: Aberrant activation of β-catenin contributes to the malignant phenotype in hepatocellular carcinoma (HCC). Hypoxia is also known to promote HCC invasion and metastasis. However, the association between β-catenin and the proinvasive role of hypoxia remains unclear. We investigated the role of β-catenin in the proinvasive consequences of hypoxia in HCC.

Experimental Design: We established in vitro and in vivo hypoxic models to investigate the expression of β-catenin in hypoxic HCC cells and its role in hypoxia-induced aggressiveness. The clinical significance of β-catenin and/or hypoxia-induced factor-1α (HIF-1α) was evaluated using HCC tissue microarrays.

Results: Hypoxia induced β-catenin overexpression and/or intracellular accumulation in four HCC cell lines through downregulating the endogenous degradation machinery, and promoted in vitro invasion and in vivo metastasis of MHCC97 and Hep3B cells. Besides morphologic changes, hypoxic MHCC97 and Hep3B cells exhibited molecular alterations consistent with epithelial-mesenchymal transition, characterized by the loss of epithelial cell markers (E-cadherin and plakoglobin) and upregulation of mesenchymal markers (vimentin and N-cadherin), as well as the increase of matrix metalloproteinase 2. However, silencing β-catenin in these hypoxic cells reversed epithelial-mesenchymal transition and repressed metastatic potential. Positive expression of β-catenin in HCC tissue microarray was associated with the expression of HIF-1α (P = 0.034), and coexpression of β-catenin and HIF-1α in HCC was correlated with shorter overall survival and time to recurrence.

Conclusion: β-Catenin in HCC is activated by hypoxia and contributes to hypoxia-induced metastatic potential. Clin Cancer Res; 16(10); 2740–50. ©2010 AACR.
Rationally Designed Pharmacogenomic Treatment Using Concurrent Capecitabine and Radiotherapy for Glioblastoma; Gene Expression Profiles Associated with Outcome
Authors: Grunda Jessica M. , Fiveash John , Palmer Cheryl A. , Cantor Alan , Fathallah-Shaykh Hassan M. , Nabors L. Burt , Johnson Martin R.
Published: May 2010

Purpose: Previous preclinical studies suggested that concurrent capecitabine and radiation could be an effective new treatment modality for glioblastoma (GBM). In the current study, we investigate toxicity and response to this regimen and explore associations between gene expression and patient outcome.

Experimental Design: Eighteen newly diagnosed GBM patients received concurrent capecitabine at 625 mg/m2 BID (25% escalation) and irradiation (60 Gy total) for 6 weeks followed by 4 weeks of capecitabine only. Maintenance capecitabine was administered for 14 days every 3 weeks until progression or unacceptable toxicity. Expression analysis of 94 genes involved in capecitabine metabolism and radiation response was done on tissues obtained before therapy. The relationship of gene expression with time-to-progression (TTP) and overall survival (OS) was investigated using univariate Cox proportional hazards regression, semi-supervised principle component analysis, and class prediction modeling.

Results: The maximum tolerated dose of capecitabine was 625 mg/m2 BID. Median patient TTP and OS were 247 and 367 days, respectively. Cox regression identified 24 genes significantly (P < 0.025) associated with patient outcome. Semi-supervised principle component analysis identified two patient populations significantly different in both TTP (P = 0.005) and OS (P = 0.015). Class prediction modeling determined that eight genes (RAD54B, MTOR, DCTD, APEX2, TK1, RRM2, SLC29A1, and ERCC6) could collectively classify patients into outcome subgroups with 100% accuracy and precision.

Conclusions: Capecitabine and concurrent radiation for newly diagnosed GBM seems to be well tolerated and comparable to temozolomide and radiation. A gene expression profile predictive of patient outcome that may be useful in patient stratification for therapy was also elucidated. Clin Cancer Res; 16(10); 2890–8. ©2010 AACR.
DNMT3L Is a Novel Marker and Is Essential for the Growth of Human Embryonal Carcinoma
Authors: Minami Kahori , Chano Tokuhiro , Kawakami Takahiro , Ushida Hiroshi , Kushima Ryoji , Okabe Hidetoshi , Okada Yusaku , Okamoto Keisei
Published: May 2010

Purpose: Testicular germ cell tumors (TGCT) have a unique epigenetic profile distinct from that of other types of cancer. Elucidation of these properties has a potential to identify novel markers for TGCTs.

Experimental Design: We conducted comprehensive analysis of DNA methyltransferase (DNMT) gene expression in TGCTs. Based on the expression profiles of DNMT genes in TGCTs, we generated a rabbit polyclonal anti-human DNMT3L antibody. We then studied the role of DNMT3L in TGCTs by the treatment of two embryonal carcinoma (EC) cell lines with a small interfering RNA system. Finally, we evaluated the immunohistochemical detection of DNMT3L in TGCT tissues. We also compared the patterns of DNMT3L immunohistochemistry with those of CD30 and SOX2.

Results: Among the DNMT genes, we found that mRNA for DNMT3L was specifically expressed in TGCTs, but neither in normal testicular tissues nor in cancer cells of somatic tissue origin. DNMT3L protein was strongly expressed in two EC cell lines, but not in the cell lines of somatic tissue origin. Transfection of small interfering RNA for DNMT3L significantly reduced DNMT3L expression and resulted in growth suppression and apoptosis in EC cells. Immunohistochemical analysis showed that DNMT3L protein was present only in EC cells, but not in the other types of TGCT components and cancer cells of somatic tissue origin. DNMT3L staining was more prominent and specific than CD30 or SOX2 staining for detecting EC cells.

Conclusion: DNMT3L is a novel marker and is essential for the growth of human embryonal carcinoma. Clin Cancer Res; 16(10); 2751–9. ©2010 AACR.
Intraindividual Comparison of Selective Arterial versus Venous 68Ga-DOTATOC PET/CT in Patients with Gastroenteropancreatic Neuroendocrine Tumors
Authors: Kratochwil Clemens , Giesel Frederik L. , López-Benítez Ruben , Schimpfky Nadine , Kunze Kirsten , Eisenhut Michael , Kauczor Hans-Ulrich , Haberkorn Uwe
Published: May 2010

Purpose: Therapy with the somatostatin analogue DOTA-(0)-Phe(1)-Tyr(3)-octreotide (DOTATOC) labeled with a β-(DOTA-Phe-Tyr-Octreotide) emitter such as 90Y or 177Lu is accepted for the palliative treatment of unresectable neuroendocrine cancer. However, the optimal route of administration has not been determined. Using positron-emission tomography (PET)-labeled 68Ga-DOTATOC, we compared selective tumoral uptake on PET/computed tomography (CT) after arterial or venous administration of the agent in patients with gastroenteropancreatic neuroendocrine tumor.

Experimental Design: Fifteen patients with neuroendocrine cancer were examined with 68Ga-DOTATOC PET/CT after intravenous (i.v.) and intraarterial (i.a.) administration within 4 weeks of each other and without any intervening therapy. Eleven patients had multifocal metastases, six were considered to have unresectable primary tumor. The intraarterial catheter was placed in the vessel supplying the main tumor burden. The standard uptake value (SUV) was used to compare intratumoral concentrations of 68Ga-DOTATOC.

Results: Compared with i.v. infusion, the i.a. infusion resulted in an increased SUV in 117 of 122 (96%) liver metastases. The average increase in SUV was 3.75-fold higher with i.a. administration. The increase in uptake for the primary tumors was dependent on the selectivity of the catheter placement, resulting in variable increases in SUV after i.a. injection (1.44- to 7.8-fold higher).

Conclusions: This study showed that uptake of DOTATOC is commonly several fold higher after selective i.a. administration in comparison with i.v. injection in both the primary tumor as well as in liver metastases of neuroendocrine cancer. Therefore, intraarterial DOTATOC is a promising drug for regionally intensified radiopeptide therapy. Clin Cancer Res; 16(10); 2899–905. ©2010 AACR.
Anti-GD3 Chimeric sFv-CD28/T-Cell Receptor ζ Designer T Cells for Treatment of Metastatic Melanoma and Other Neuroectodermal Tumors
Authors: Lo Agnes S.Y. , Ma Qiangzhong , Liu David L. , Junghans Richard P.
Published: May 2010

Purpose: The aims of this study are to compare antitumor activities of two generations of GD3-specific chimeric antigen receptors (CAR) in human primary T lymphocytes in vitro and to evaluate the antitumor efficacy of using a combination of systemic infusion of interleukin-2 (IL2) and designer T cells to eradicate subcutaneous established GD3+ melanoma in nude mice.

Experimental Design: Antitumor activities were compared for two generations of designer T cells, the progenitor first-generation with immunoglobulin T-cell receptor (TCR) with Signal 1 and the second-generation designer T cells with Signal 1+2. Osmotic IL2 pumps were used to deliver the maximum tolerated dose of IL2 to enhance the antitumor effects of designer T cells on subcutaneous established melanoma in nude mice.

Results: Melanoma is associated with high expression of ganglioside GD3, which has been targeted with modest effect in antibody therapies. We previously showed that an anti-GD3 CAR (sFv-TCRζ) will recruit T cells to target this non–T-dependent antigen, with potent killing of melanoma cells. Here, we report the addition of a CD28 costimulation domain to create a second-generation CAR, called Tandem for two signals. We show that this Tandem sFv-CD28/TCRζ receptor on T cells confers advantages of improved cytokine secretion, cytotoxicity, proliferation, and clonal expansion on tumor contact versus the same CAR without costimulation. In an adoptive transfer model using established melanoma tumors, designer T cells with CD28 showed a 50% rate of complete remissions but only where IL2 was supplemented.

Conclusions: As a reagent for clinical development, the second-generation product is shown to have superior properties to warrant its preference for clinical designer T-cell immunotherapy for melanoma and other tumors. Systemic IL2 was required for optimal activity in an established tumor model. Clin Cancer Res; 16(10); 2769–80. ©2010 AACR.