bluuebunny/crossref_metadata_2025_split huggingface dataset:
H-NS Binding and Repression of the
ctx
Promoter in
Vibrio cholerae
Authors: Stonehouse Emily A. , Hulbert Robin R. , Nye Melinda B. , Skorupski Karen , Taylor Ronald K. 
Published: December 2010

ABSTRACT

Expression of the
ctx
and
tcp
genes, which encode cholera toxin and the toxin coregulated pilus, the
Vibrio cholerae
O1 virulence determinants having the largest contribution to cholera disease, is repressed by the nucleoid-associated protein H-NS and activated by the AraC-like transcriptional regulator ToxT. To elucidate the molecular mechanism by which H-NS controls transcription of the
ctxAB
operon, H-NS repression and binding were characterized by using a promoter truncation series, gel mobility shift assays, and DNase I footprinting. Promoter regions found to be important for H-NS repression correlated with
in vitro
binding. Four main H-NS binding regions are present at
ctx
. One region overlaps the high-affinity ToxT binding site and extends upstream, another overlaps the ToxT low-affinity binding site around the −35 element, and the remaining two are located adjacent to one another downstream of the transcriptional start site. Competition for binding to the overlapping H-NS/ToxT binding sites was observed in gel mobility shift assays, where ToxT was found to displace H-NS from the
ctx
promoter region. In addition, regulatory differences between the
ctx
and
tcpA
promoters were examined. H-NS was found to have a higher relative binding affinity for the
ctx
promoter than for the
tcpA
promoter
in vitro
. In contrast to ToxT-dependent activation of the
tcpA
promoter, ToxT activation of
ctx
did not require the C-terminal domain of the α-subunit of RNA polymerase. These findings demonstrate that transcriptional regulation of
ctx
and
tcpA
by H-NS and ToxT is mechanistically distinct, and this may lead to important differences in the expression of these coregulated genes.
Preliminary study on the correlation between grading and histology of solitary pulmonary nodules and contrast enhancement and [18F]fluorodeoxyglucose standardised uptake value after evaluation by dynamic multiphase CT and PET/CT
Authors: Cappabianca Salvatore , Porto Annamaria , Petrillo Mario , Greco Barbara , Reginelli Alfonso , Ronza Francesco , Setola Francesca , Rossi Giovanni , Di Matteo Andrea , Muto Roberto , De Rimini Maria Luisa , Piccolo Sergio , Catalano Mara , Muto Pietro , De Rosa Nicoletta , Barra Enrica , De Rosa Ilaria , Antinolfi Francesca , Antinolfi Giuseppe , Caputi Mario , Brunese Luca , Grassi Roberto , Rotondo Antonio 
Published: December 2010

AimTo evaluate whether the histology and grading of solitary pulmonary nodules (SPNs) correlated with the results of dynamic multiphase multidetector CT (MDCT) and the [18F]fluorodeoxyglucose standardised uptake value (SUV) in 30 patients.MethodsChest x-rays of 270 patients with incidentally detected SPNs were retrospectively evaluated. Thirty patients with histologically proven SPNs were enrolled. On MDCT and positron emission tomography (PET)/CT images, two experts measured the density of nodules in all perfusion phases and the SUV. Net enhancement (NE) was calculated by subtracting peak pre-contrast density from peak post-contrast density. The Pearson test was used to correlate nodule NE, SUV, grading, histology and diameter.ResultsOf the 30 malignant SPNs, six were classified as G1 (median NE, 31.5 Hounsfield units (HU); median SUV, 4.8 units), 15 were classified as G2 (median NE, 49 HU; median SUV, 6 units), and nine were classified as G3 (median NE, 32 HU; median SUV, 4.5 units). A highly negative correlation was found in G3 SPNs between NE and the corresponding diameters (r=−0.834; p=0.00524). NE increased with the increase in diameter (r=0.982; p=0.284). SUV increased as the SPN diameter increased (r=0.789; p=0.421). NE and SUV were higher in G2 than G1 SPNs, and lower in G2 than G3 SPNs (r=0.97; p=0.137).ConclusionsThe significant correlation in dedifferentiated (G3) SPNs between NE and diameter (r=−0.834; p=0.00524) supports the theory that stroma and neoangiogenesis are fundamental in SPN growth. The highly negative correlation between NE and diameter demonstrates a net decrease in perfusion despite an increase in dimension. The multidisciplinary approach used herein may result in a more precise prognosis and consequently a better therapeutic outcome, particularly in patients with undifferentiated lung cancer.
MLH1 function is context dependent in colorectal cancers
Authors: Jackson Thomas , Ahmed Mohamed A H , Seth Rashmi , Jackson Darryl , Ilyas Mohammad 
Published: December 2010

Background and aimsLoss of mismatch repair (MMR) function in sporadic colorectal cancer occurs most commonly because of inactivation of MLH1, and it causes an increase in mutation rate. However, it is uncertain whether loss of MMR alters any other cellular function. The aim of this study was to investigate the role of MMR in regulating cell numbers and apoptosis.MethodsMLH1 protein levels were manipulated by (a) cloning and forcibly expressing MLH1 in HCT116 (a cell line with MLH1 mutation) and RKO (a cell line with MLH1 silencing), and (b) knockdown of MLH1 in SW480 (a cell line with normal MMR function). Cell number and apoptotic bodies were measured in standard and ‘high stress’ (ie, after staurosporine exposure) conditions.ResultsRestoration of MLH1 function in HCT116 and RKO resulted in increased cell number (p<0.001 for both cell lines) and decreased numbers of floating apoptotic bodies (p<0.01 in HCT116) in standard culture conditions. However, on induction of apoptotic stress, restoration of MLH1 resulted in reduced cell numbers (p<0.005). Knockdown of MLH1 in SW480 had no effect on cell numbers or apoptosis.ConclusionsMLH1 function may be context dependent: in ‘low stress’ conditions it may act to inhibit apoptosis, while in ‘high stress’ conditions it may induce apoptosis. However, within the context of chromosomal instability, the effect of MLH1 on cell numbers is limited.
Blood pressure measurement in the artery proximal and distal to an intra-arterial embolus during thrombolytic therapy
Authors: Sorimachi Takatoshi , Morita Kenichi , Ito Yasushi , Fujii Yukihiko 
Published: December 2010

Background and aimWhen a cerebral embolism occurs, pressure gradients in the arteries between sites proximal and distal to the embolus exert hydromechanical forces that push the embolus distally, and potentially affect successful revascularization during clot removal. We investigated the relationships between blood pressures that occur immediately distal and proximal to the embolus, systemic blood pressure and clinical variables.Methods36 patients with embolism of the internal carotid artery (13 patients) or the proximal middle cerebral artery (23 patients) were treated using intra-arterial thrombolysis. The mean blood pressure (MBP) at the sites proximal (proximal MBP) and distal (distal MBP) to the embolus was measured with a microcatheter. Simultaneously, the systemic MBP was recorded by cuff measurement.ResultsProximal, distal and systemic MBPs (mean±SD) were 95.2±13.2 mm Hg, 35.9±13.5 mm Hg and 98.2±12.2 mm Hg, respectively. The proximal MBP was significantly higher in the patients with systemic MBP≥100 mm Hg than those with systemic MBP<100 mm Hg (p<0.05). The distal MBP showed no difference between the high and normal systemic MBP groups.ConclusionsHigher systemic blood pressure produced stronger hydromechanical forces on the clot, forming a proximal–distal blood pressure gradient across the clot. The stronger hydromechanical force could result in higher compaction of the clot, thus making it more difficult to remove.
FUS/TLS Is a Novel Mediator of Androgen-Dependent Cell-Cycle Progression and Prostate Cancer Growth
Authors: Brooke Greg N. , Culley Rachel L. , Dart D. Alwyn , Mann David J. , Gaughan Luke , McCracken Stuart R. , Robson Craig N. , Spencer-Dene Bradley , Gamble Simon C. , Powell Sue M. , Wait Robin , Waxman Jonathan , Walker Marjorie M. , Bevan Charlotte L. 
Published: December 2010

Abstract
Progression of prostate cancer is highly dependent upon the androgen receptor pathway, such that knowledge of androgen-regulated proteins is vital to understand and combat this disease. Using a proteomic screen, we found the RNA-binding protein FUS/TLS (Fused in Ewing's Sarcoma/Translocated in Liposarcoma) to be downregulated in response to androgen. FUS has recently been shown to be recruited by noncoding RNAs to the regulatory regions of target genes such as cyclin D1, in which it represses transcription by disrupting complex formation. Here we show that FUS has some characteristics of a putative tumor suppressor, as its overexpression promoted growth inhibition and apoptosis of prostate cancer cells, whereas its knockdown increased cell proliferation. This effect was reproducible in vivo, such that increasing FUS levels in tumor xenografts led to dramatic tumor regression. Furthermore, FUS promoted conditions that favored cell-cycle arrest by reducing the levels of proliferative factors such as cyclin D1 and Cdk6 and by increasing levels of the antiproliferative Cdk inhibitor p27. Immunohistochemical analysis revealed that FUS expression is inversely correlated with Gleason grade, demonstrating that patients with high levels of FUS survived longer and were less likely to have bone metastases, suggesting that loss of FUS expression may contribute to cancer progression. Taken together, our results address the question of how androgens regulate cell-cycle progression, by demonstrating that FUS is a key link between androgen receptor signaling and cell-cycle progression in prostate cancer. Cancer Res; 71(3); 914–24. ©2010 AACR.
NKX2.2 Suppresses Self-Renewal of Glioma-Initiating Cells
Authors: Muraguchi Teruyuki , Tanaka Shingo , Yamada Daisuke , Tamase Akira , Nakada Mitsutoshi , Nakamura Hideo , Hoshii Takayuki , Ooshio Takako , Tadokoro Yuko , Naka Kazuhito , Ino Yasushi , Todo Tomoki , Kuratsu Jun-ichi , Saya Hideyuki , Hamada Jun-ichiro , Hirao Atsushi 
Published: December 2010

Abstract
Glioblastoma (GBM) is the most aggressive and destructive form of brain cancer. Animal models that can unravel the mechanisms underlying its progression are needed to develop rational and effective molecular therapeutic approaches. In this study, we report the development of mouse models for spontaneous gliomas representing distinct progressive stages of disease that are governed by defined genetic alterations. Neural stem/progenitor cell (NPC)-specific constitutive Ras activation in vivo plus p53 deficiency led to development of primarily anaplastic astrocytoma (grade III), whereas combined loss of p53 plus p16Ink4a/p19Arf led to development of GBM (grade IV) at 100% penetrance within 6 weeks. These glioma models showed enhanced stem cell properties (stemness) accompanied by malignant progression. Notably, we determined that, in our models and in human specimens, downregulation of the homeodomain transcription factor NKX2.2, which is essential for oligodendroglial differentiation, was correlated with increased tumor malignancy. NKX2.2 overexpression by GBM-derived glioma-initiating cells (GIC) induced oligodendroglial differentiation and suppressed self-renewal capacity. By contrast, Nkx2.2 downregulation in mouse NPCs accelerated GBM formation. Importantly, the inhibitory effects of NXK2.2 on GIC self-renewal were conserved in human cells. Thus, our mouse models offer pathobiologically significant advantages to investigate the nature of brain tumors, with improved opportunities to develop novel mechanism-based therapeutic approaches. Cancer Res; 71(3); 1135–45. ©2010 AACR.
The Metastasis-Associated microRNA miR-516a-3p Is a Novel Therapeutic Target for Inhibiting Peritoneal Dissemination of Human Scirrhous Gastric Cancer
Authors: Takei Yoshifumi , Takigahira Misato , Mihara Keichiro , Tarumi Yuzo , Yanagihara Kazuyoshi 
Published: December 2010

Abstract
Although aberrant microRNA (miRNA) is expressed in different types of human cancer tissues, its pathophysiologic role and the relevance of tumorigenesis and metastasis are still largely unknown. Here, we defined miRNAs involved in cancer metastasis (metastamirs) using an established mouse model for peritoneal dissemination of human scirrhous gastric carcinoma cells. Highly metastatic derivatives (44As3 cells) were derived from the parental cells originally isolated from patients (HSC-44PE cells). Using microarray analysis to identify differentially expressed miRNAs in 44As3 and HSC-44PE cells, we focused on miR-516a-3p as a candidate antimetastatic miRNA (antimetastamir) whose functions in cancer had not been studied. We confirmed attenuated expression of miR-516a-3p in 44As3 cells compared with HSC-44PE cells by Northern blot analysis and quantitative reverse transcriptase PCR. Stable ectopic overexpression in 44As3-miR-516a-3p cells permitted identification of sulfatase 1 as a direct target of the miRNA, through use of the isobaric tagging reagent iTRAQ and the QSTAR Elite Hybrid LC-MS/MS system. Sulfatase 1 is known to remove 6-O-sulfates from heparan sulfate proteoglycans on the cell surface, causing release of membrane-bound Wnt ligands from cells. Consistent with this function, Western blot analyses revealed high levels of Wnt3a, Wnt5a, and nuclear β-catenin accumulation in 44As3 cells but relatively reduced levels in 44As3-miR-516a-3p cells. Notably, orthotopic inoculation of nude mice with 44As3-miR-516a-3p cells yielded significantly longer survival periods compared with mice inoculated with control 44As3 cells. Through atelocollagen-mediated delivery of an miR-516a-3p expression vector into orthotopic 44As3 tumors, we documented its feasibility as a treatment agent. Our findings define the miRNA miR-516-3p as an antimetastamir with potential therapeutic applications in blocking metastatic dissemination of gastric cancers. Cancer Res; 71(4); 1442–53. ©2010 AACR.
Recovery of Anoikis in Src-Transformed Cells and Human Breast Carcinoma Cells by Restoration of the SIRPα1/SHP-2 Signaling System
Authors: Hara Kazuo , Senga Takeshi , Biswas Md. Helal Uddin , Hasegawa Hitoki , Ito Satoko , Hyodo Toshinori , Hirooka Yoshiki , Niwa Yasumasa , Goto Hidemi , Hamaguchi Michinari 
Published: December 2010

Abstract
Src kinase dysregulation contributes to cancer progression but mechanistic understanding for this contribution remains incomplete. Signal regulatory protein α1 (SIRPα1) is a tumor suppressor that is constitutively suppressed in v-Src-transformed cells, where restoration of SIRPα1 expression inhibits anchorage-independent growth. In this study, we investigated the role of the protein tyrosine phosphatase-2 (SHP-2) in SIRPα1 activity. SHP-2 suppression resulted in a blockade of SIRPα1-mediated inhibition of anchorage-independent growth. Notably, we found that SIRPα1 did not act in v-Src-transformed cells by triggering cell growth arrest but by eliciting a suspension-selective apoptosis (anoikis), and that SHP-2 was required for this effect. Furthermore, we found that SHP-2 was crucial for recovery of stress fiber and focal contact formation by SIRPα1 in v-Src-transformed cells. Finally, we found that SIRPα1/SHP-2 signaling regulates anoikis in human breast carcinoma cells with activated c-Src. Taken together, our findings define SHP-2 as an essential component of tumor suppression and anoikis mediated by SIRPα1 in human breast carcinoma cells as well as in v-Src-transformed cells. Cancer Res; 71(4); 1229–34. ©2010 AACR.
Polo-Like Kinase 1 is a Therapeutic Target in High-Risk Neuroblastoma
Authors: Ackermann Sandra , Goeser Felix , Schulte Johannes H. , Schramm Alexander , Ehemann Volker , Hero Barbara , Eggert Angelika , Berthold Frank , Fischer Matthias 
Published: December 2010

Abstract
Purpose: High-risk neuroblastoma remains a therapeutic challenge for pediatric oncologists. The Polo-like kinase 1 (PLK1) is highly expressed in many human cancers and is a target of the novel small-molecule inhibitor BI 2536, which has shown promising anticancer activity in adult malignancies. Here, we investigated the effect of BI 2536 on neuroblastoma cells in vitro and in vivo to explore PLK1 as a potential target in high-risk neuroblastoma therapy.
Experimental Design: PLK1 transcript levels were analyzed by microarrays in 476 primary neuroblastoma specimens, and correlation with prognostic markers and patient outcome was examined. To explore the effect of PLK1 inhibition on neuroblastoma cells, 7 cell lines were treated with BI 2536 and changes in growth properties were determined. Furthermore, nude mice with IMR-32 and SK-N-AS xenografts were treated with BI 2536.
Results: PLK1 is highly expressed in unfavorable neuroblastoma and in neuroblastoma cell lines. Expression of PLK1 is associated with unfavorable prognostic markers such as stage 4, age &gt;18 months, MYCN amplification, unfavorable gene expression-based classification, and adverse patient outcome (P &lt; 0.001 each). On treatment with nanomolar doses of BI 2536, all neuroblastoma cell lines analyzed showed significantly reduced proliferation, cell cycle arrest, and cell death. Moreover, BI 2536 abrogated growth of neuroblastoma xenografts in nude mice.
Conclusions: Elevated PLK1 expression is significantly associated with high-risk neuroblastoma and unfavorable patient outcome. Inhibition of PLK1 using BI 2536 exhibits strong antitumor activity on human neuroblastoma cells in vitro and in vivo, opening encouraging new perspectives for the treatment of high-risk neuroblastoma. Clin Cancer Res; 17(4); 1–11. ©2010 AACR.
Hyperhomocysteinemia does not affect global DNA methylation and nicotinamide N-methyltransferase expression in mice
Authors: Bromberg Anna , Levine Joseph , Belmaker RH , Agam Galila 
Published: December 2010

DNA methylation is coupled with one-carbon metabolism involving homocysteine/methionine interconversion. Correlation between plasma homocysteine levels and leukocyte global DNA methylation was reported but not always replicated. Nicotinamide N-methyltransferase (NNMT) is a determinant of plasma homocysteine levels. Findings suggest alteration of one-carbon metabolism in schizophrenia etiology; hyperhomocysteinemia was observed in schizophrenia. A recent study carried out by the authors of this paper found an association between NNMT and schizophrenia and decreased post-mortem brain NNMT mRNA levels. The present study assessed the interrelationship between brain and leukocytes global DNA methylation and plasma homocysteine levels, and between hyperhomocysteinemia and brain NNMT expression. Mice were administered homocysteine in drinking water. Percentage global genome DNA methylation was measured using the cytosine-extension method, and NNMT expression was measured using real-time quantitative reverse transcriptase PCR (qRT-PCR). Homocysteine administration resulted in a 10-fold increase in plasma homocysteine. However, there was no change in global DNA methylation in lymphocytes or in the frontal cortex. No significant intra-individual correlation was found between global DNA methylation in leukocytes and frontal cortex, suggesting that leukocyte global DNA methylation may not serve as a marker for brain global DNA methylation. No difference was found in NNMT expression in homocysteine-treated mice compared with control mice. In conclusion, relatively short-term hyperhomocysteinemia in mice does not reproduce or lead to alterations reported in one-carbon metabolism in disorders associated with lifelong elevated plasma homocysteine.
Correlation between serum gastrin and cellular proliferation in Barrett’s esophagus
Authors: Green Daniel A. , Mlynarczyk Carrie M. , Vaccaro Benjamin J. , Capiak Kristina M. , Quante Michael , Lightdale Charles J. , Abrams Julian A. 
Published: December 2010

Background: Patients with Barrett’s esophagus (BE) are commonly treated with proton-pump inhibitors (PPIs) to minimize the exposure of esophageal mucosa to stomach acid. However, the use of these medications can lead to significant hypergastrinemia in a subset of patients, which is concerning due to the known tumorigenic and proliferative effects of gastrin. The present pilot study aims to investigate a potential correlation between serum gastrin and cellular proliferation in BE. Methods: We performed a cross-sectional analysis of patients with nondysplastic BE on PPI therapy. Fasting serum gastrin was measured on the same day as esophageal biopsies were obtained. These biopsies were then stained with Ki-67 nuclear antibody. Pearson’s correlation coefficient was calculated to assess the relationship between Ki-67 index and ln(gastrin). Results: A total of 10 patients were included in the study. The mean age was 62.6 (±8.4) years and 5 patients were male. The median serum gastrin level was 45.2 pM (interquartile range [IQR] 33–113) and the median Ki-67 index was 49.6% (IQR 23–64). We found a statistically significant positive correlation between Ki-67 index and ln(gastrin) ( r = 0.64; p = 0.05). Conclusions: In nondysplastic BE patients on PPI therapy, serum gastrin levels were significantly correlated with cellular proliferation. These pilot data lend support to a potential causal effect of gastrin on neoplastic progression in BE. Longitudinal studies of patients with BE are needed to determine whether hypergastrinemia is a risk factor for the development of dysplasia and adenocarcinoma or could be used as a biomarker for disease progression.
Expression of functional KISS1 and KISS1R system is altered in human pituitary adenomas: evidence for apoptotic action of kisspeptin-10
Authors: Martínez-Fuentes Antonio J , Molina Marcelo , Vázquez-Martínez Rafael , Gahete Manuel D , Jiménez-Reina Luis , Moreno-Fernández Jesús , Benito-López Pedro , Quintero Ana , de la Riva Andrés , Diéguez Carlos , Soto Alfonso , Leal-Cerro Alfonso , Resmini Eugenia , Webb Susan M , Zatelli Maria C , degli Uberti Ettore C , Malagón María M , Luque Raul M , Castaño Justo P 
Published: December 2010

ContextKISS1 was originally identified as a metastasis-suppressor gene able to inhibit tumor progression. KISS1 gene products, the kisspeptins, bind to a G-protein-coupled receptor (KISS1R, formerly GPR54), which is highly expressed in placenta, pituitary, and pancreas, whereas KISS1 mRNA is mainly expressed in placenta, hypothalamus, striatum, and pituitary.Objective and designKISS1/KISS1R pituitary expression profile, coupled to their anti-tumoral capacities, led us to hypothesize that this system may be involved in the biology of pituitary tumors. To explore this notion, expression levels of KISS1R and KISS1 were evaluated in normal and adenomatous pituitaries. Additionally, functionality of this system was assessed by treating dispersed pituitary adenoma cells in primary culture with kisspeptin-10 and evaluating intracellular calcium kinetics and apoptotic rate.ResultsBoth KISS1 and KISS1R were expressed in normal pituitary, whereas this simultaneous expression was frequently lost in pituitary tumors, where diverse patterns of KISS1/KISS1R expression were observed that differed among distinct types of pituitary adenomas. Measurement of calcium kinetics revealed that kisspeptin-10 elicits a remarkable increase in [Ca2+]i in individual cells from four out of the five GH-producing adenomas studied, whereas cells derived from non-functioning pituitary adenomas (NFPA, n=45) did not respond. In contrast, kisspeptin-10 treatment increased the apoptotic rate in cells derived from both GH-producing and NFPA.ConclusionsThese results provide primary evidence that KISS1 and KISS1R expression can be differentially lost in pituitary tumor subtypes, where this system can exert functional, proapoptotic actions, and thereby offer novel insights to investigate the biology and therapeutic options to treat these tumors.