tbuckley/cabot-search huggingface dataset:
Characterization of the Hollow Fiber Assay for the Determination of Microtubule Disruption<b><i>In vivo</i></b>
Authors: Marie Suggitt, David J. Swaine, George R. Pettit, Michael C. Bibby
Journal: Clinical Cancer Research (2004)

The hollow fiber assay is used successfully as a routine in vivo screening model to quantitatively define anticancer activity by the National Cancer Institute. This study investigates whether the hollow fiber assay can be used as a short-term in vivo model to demonstrate specific pharmacodynamic end points, namely microtubule and cell cycle disruption.The growth of A549 cells was characterized within hollow fibers over 5 days in vivo at both subcutaneous (s.c.) and intraperitoneal (i.p.) sites. Drugs were administered on day 4 (i.p.).At 24 hours, cells were retrieved from fibers at both i.p. and s.c. sites of paclitaxel-treated (20 mg/kg) and combretastatin A1 phosphate-treated (150 mg/kg) mice. Cell cycle analysis after paclitaxel treatment revealed a mean G(2)-M phase population of 48.04% (i.p.) and 25.76% (s.c.) compared with vehicle group mice (6.78 and 5.56%, respectively; P = <0.001 and 0.005, respectively). Tumor cells retrieved from combretastatin A1 phosphate-treated mice had a mean G2-M phase population of 36.3% (i.p.) and 29.36% (s.c.) compared with cells retrieved from vehicle group mice (5.58 and 5.49%, respectively; P = <0.001). Using fluorescence and laser-confocal microscopy, paclitaxel was revealed to induce the formation of spindle asters and tubulin polymerization. Combretastatin A1 phosphate was shown to hold cells in mitosis. Changes in nuclear morphology were also observed.These data demonstrate that the hollow fiber assay can be used as a short-term in vivo model for studying the pharmacodynamic effects of both standard and novel compounds on microtubules. Evidence has also been provided to support the routine use of the in vivo hollow fiber assay for demonstrating the mechanism of action of a drug.
Cytochrome <i>P</i>450 1B1 Expression in Glial Cell Tumors: An Immunotherapeutic Target
Authors: Julia A. Barnett, Diana L. Urbauer, Graeme I. Murray, Gregory N. Fuller, Amy B. Heimberger
Journal: Clinical Cancer Research (2007)

Abstract Purpose: Among central nervous system malignancies, cytochrome P450 1B1 (CYP1B1) expression has only been characterized in medulloblastoma. An immunotherapeutic agent targeting this antigen was shown to safely stimulate a good immune response. To evaluate the viability of further research efforts targeting this antigen, we examined the expression of CYP1B1 in glial cell malignancies. Experimental Design: We studied the frequency and extent of CYP1B1 expression by immunohistochemical analysis in 269 glial tumors (including all major pathologic types) on a tissue microarray. Results were categorized by percentage of cells stained and intensity of cytoplasmic staining within cells. Correlation of CYP1B1 expression with patient prognosis was evaluated by univariate and multivariate analyses. Results: Overall, increased CYP1B1 expression in glial tumors was associated with decreased patient survival time (P &amp;lt; 0.0014 for both percentage and intensity of staining). A significant difference existed in percentage and intensity of staining between astrocytic and oligodendroglial tumors (P = 0.0002 and 0.0003, respectively), between grades of tumors (P &amp;lt; 0.0001 and 0.0079), and between pathologic types of tumors (P &amp;lt; 0.0001 and 0.0339). Positive CYP1B1 staining was seen in 81% of glioblastomas, 84% of anaplastic astrocytomas, 61% of oligodendrogliomas, and 67% of anaplastic oligodendrogliomas. Paradoxically, within specific tumor pathologies, there was a trend toward increased survival as CYP1B1 expression increased. However, in the multivariate analysis, this trend disappeared, and CYP1B1 expression seemed prognostically neutral. Conclusion: CYP1B1 is frequently expressed in a variety of gliomas and could be used as a target for immunotherapy.
Cellular and Subcellular Distribution of Polycystin-2, the Protein Product of the PKD2 Gene
Authors: LUKAS FOGGENSTEINER, A. PAUL BEVAN, RUTH THOMAS, NICHOLAS COLEMAN, CATHERINE BOULTER, JOHN BRADLEY, OXANA IBRAGHIMOV-BESKROVNAYA, KATHERINE KLINGER, RICHARD SANDFORD
Journal: Journal of the American Society of Nephrology (2000)

Abstract. Mutations in the PKD1 and PKD2 genes account for 85 and 15% of cases of autosomal dominant polycystic kidney disease, respectively. Polycystin-2, the product of the PKD2 gene, is predicted to be an integral membrane protein with homology to a family of voltage-activated Ca 2+ channels. In vitro studies suggest that it may interact with polycystin-1, the PKD1 gene product, via coiled-coil domains present in their C-terminal domains. In this study, the cellular and subcellular distribution of polycystin-2 is defined and compared with polycystin-1. A panel of rabbit polyclonal antisera was raised against polycystin-2 and shown to recognize a single band consistent with polycystin-2 in multiple tissues and cell lines by immunoprecipitation and Western blotting. Immunostaining of human and murine renal tissues demonstrated widespread and developmentally regulated expression of polycytin-2, with highest levels in the kidney in the thick ascending limbs of the loop of Henle and the distal convoluted tubule. In contrast, polycystin-1 expression, while localizing to the same tubular segments, was highest in the collecting ducts. Immunohistochemical staining and immunofluorescence microscopy localized polycystin-2 to the basolateral plasma membrane of kidney tubular epithelial cells compared with the junctional localization of polycystin-1. Differences in the developmental, cellular, and subcellular expression of polycystin-1 and polycystin-2 suggest that they may be able to function independently of each other in addition to a potential in vivo interaction via their C-termini.
Rho GTPases, Statins, and Nitric Oxide
Authors: Yoshiyuki Rikitake, James K. Liao
Journal: Circulation Research (2005)

The lipid-lowering drugs, 3-hydroxy-3-methylgulutaryl-coenzyme A (HMG-CoA) reductase inhibitors or statins, are used in the prevention and treatment of cardiovascular diseases. Recent experimental and clinical studies suggest that statins may exert vascular protective effects beyond cholesterol reduction. For example, statins improve endothelial function by cholesterol-dependent and -independent mechanisms. The cholesterol-independent or “pleiotropic” effects of statins include the upregulation and activation of endothelial NO synthase (eNOS). Because statins inhibit an early step in the cholesterol biosynthetic pathway, they also inhibit the synthesis of isoprenoids such as farnesylpyrophosphate and geranylgeranylpyrophosphate, which are important posttranslational lipid attachments for intracellular signaling molecules such as the Rho GTPases. Indeed, decrease in Rho GTPase responses as a consequence of statin treatment increases the production and bioavailability of endothelium-derived NO. The mechanism involves, in part, Rho/Rho-kinase (ROCK)-mediated changes in the actin cytoskeleton, which leads to decreases in eNOS mRNA stability. The regulation of eNOS by Rho GTPases, therefore, may be an important mechanism underlying the cardiovascular protective effect of statins.
Tumor Stroma Interactions Induce Chemoresistance in Pancreatic Ductal Carcinoma Cells Involving Increased Secretion and Paracrine Effects of Nitric Oxide and Interleukin-1β
Authors: Susanne Müerköster, Kai Wegehenkel, Alexander Arlt, Maike Witt, Bence Sipos, Marie-Luise Kruse, Thorsten Sebens, Günter Klöppel, Holger Kalthoff, Ulrich R. Fölsch, Heiner Schäfer
Journal: Cancer Research (2004)

Abstract Pancreatic ductal carcinoma is characterized by a profound chemoresistance. As we have shown previously, these tumor cells can develop chemoresistance by interleukin (IL)-1β in an autocrine and nuclear factor-κB-dependent fashion. Because pancreatic ductal carcinoma contains many mesenchymal stromal cells, we further investigated how tumor–stroma interactions contribute to chemoresistance by using a transwell coculture model, including murine pancreatic fibroblasts and the chemosensitive human pancreatic carcinoma cell lines T3M4 and PT45-P1. If cultured with fibroblast-conditioned medium or kept in coculture with fibroblasts, both cell lines became much less sensitive toward treatment with etoposide than cells cultured under standard conditions. Furthermore, the secretion of IL-1β in T3M4 and PT45-P1 cells was increased by the fibroblasts, and IL-1β-receptor blockade abolished the resistance-inducing effect during cocultivation. This stimulated IL-1β secretion could be attributed to nitric oxide (NO) released by the fibroblasts as an IL-1β-inducing factor. Although both tumor cells secreted only little NO, which was in line with undetectable inducible nitric oxide synthase (iNOS) expression, fibroblasts exhibited significant iNOS expression and NO secretion that could be further induced by the tumor cells. Incubation of T3M4 and PT45-P1 cells with the NO donor S-Nitroso-N-acetyl-D,l-penicillamine up-regulated IL-1β secretion and conferred resistance toward etoposide-induced apoptosis. Conversely, the resistance-inducing effect of the fibroblasts was significantly abolished, when the specific iNOS inhibitor aminoguanidine was added during coculture. Immunohistochemistry on tissue sections from human pancreatic ductal carcinoma also revealed iNOS expression in stromal cells and IL-1β expression in tumor cells, thus supporting the in vitro findings. These data clearly demonstrate that fibroblasts contribute to the development of chemoresistance in pancreatic carcinoma cells via increased secretion of NO, which in turn leads to an elevated release of IL-1β by the tumor cells. These findings substantiate the implication of tumor–stromal interactions in the chemoresistance of pancreatic carcinoma.
Glycolytic activity in human synovial lining cells in rheumatoid arthritis.
Authors: B Henderson, L Bitensky, J Chayen
Journal: Annals of the Rheumatic Diseases (1979)

It was conceivable that the previously reported elevated pentose-shunt activity in human rheumatoid synoviocytes could be at the expense of glycolytic activity. To test this possibility the activities of glyceraldehyde 3-phosphate and lactate dehydrogenase, the two dehydrogenase enzymes of the latter pathway, have been investigated in the synovial lining cells in fresh sections of nonrheumatoid and rheumatoid synovial tissue. To measure the activity solely in the lining cells, apart from that in underlying infiltrating cells, quantitative cytochemical reactions have been used; the activities were measured by microdensitometry. The results showed highly and significantly increased activity of both enzymes in the rheumatoid cells. Increased activity was also found in synoviocytes in nonrheumatoid synovial tissue after trauma, so that the increased activity of these enzymes is not characteristic of the rheumatoid condition. However, the results indicate that the increased pentose shunt activity in rheumatoid synovial lining cells is not at the expense of glycolytic activity but may be part of an enhanced potential for utilising glucose 6-phosphate in these cells.
A Differential Gene Expression Profile Reveals Overexpression of <b> <i>RUNX1/AML1</i> </b> in Invasive Endometrioid Carcinoma
Authors: Jesús Planagumà, María Díaz-Fuertes, Antonio Gil-Moreno, Miguel Abal, Marta Monge, Angel García, Teresa Baró, Timothy M. Thomson, Jordi Xercavins, Francesc Alameda, Jaume Reventós
Journal: Cancer Research (2004)

Abstract Endometrial carcinoma is the most common gynecological malignant disease in industrialized countries. Two clinicopathological types of endometrial carcinoma have been described, based on estrogen relation and grade: endometrioid carcinoma (EEC) and non-EEC (NEEC). Some of the molecular events that occur during the development of endometrial carcinoma have been characterized, showing a dualistic genetic model for EEC and NEEC. However, the molecular bases for endometrial tumorigenesis are not clearly elucidated. In the present work, we attempted to identify new genes that could trigger cell transformation in EEC. We analyzed the differential gene expression profile between tumoral and nontumoral endometrial specimens with cDNA array hybridization. Among the 53 genes for which expression was found to be altered in EEC, the acute myeloid leukemia proto-oncogene, RUNX1/AML1, was one of the most highly up-regulated. The gene expression levels of RUNX1/AML1 were quantified by real-time quantitative PCR, and protein levels were characterized by tissue array immunohistochemistry. Real-time quantitative PCR validated RUNX1/AML1 up-regulation in EEC and demonstrated a specific and significantly stronger up-regulation in those tumor stages associated with myometrial invasion. Furthermore, tissue array immunohistochemistry showed that RUNX1/AML1 up-regulation correlates to the process of tumorigenesis, from normal atrophic endometrium to simple and complex hyperplasia and then, on to carcinoma. These results demonstrate for the first time the up-regulation of RUNX1/AML1 in EEC correlating with the initial steps of myometrial infiltration.
Coronary Embolization With Myocardial Infarction
Authors: E. Henry Lamkin
Journal: JAMA (1965)

CORONARY embolization is an infrequent cause of myocardial infarction. Oakley and his associates<sup>1</sup>were able to collect only 90 cases from the literature, to which they added five cases of their own. Wenger and Bauer<sup>2</sup>found 11 cases of coronaryartery embolism in 17,469 consecutive autopsy cases at Mount Sinai Hospital, New York, for a general necropsy incidence of 0.06%. The actual incidence of coronary occlusion due to embolism is unknown. Although 50% of cases of coronary embolism are associated with bacterial endocarditis, several other sources of emboli have been less commonly reported. In addition to paradoxical embolization, emboli may arise from any one of a number of sites in the left side of the heart and its immediate tributaries. The advent of open-heart surgery, and particularly valve prosthesis, has introduced a new source for thrombus formation and subsequent embolization, namely thrombosis on the prosthetic valve. This paper presents the
Heat Shock Protein 70 Gene Transfection Protects Mitochondrial and Ventricular Function Against Ischemia-Reperfusion Injury
Authors: Jay Jayakumar, Ken Suzuki, Ivan A. Sammut, Ryszard T. Smolenski, Mak Khan, Najma Latif, Haitham Abunasra, Bari Murtuza, Mohamed Amrani, Magdi H. Yacoub
Journal: Circulation (2001)

Upregulation of heat shock protein 70 (HSP70) is beneficial in cardioprotection against ischemia-reperfusion injury, but the mechanism of action is unclear. We studied the role of HSP70 overexpression through gene therapy on mitochondrial function and ventricular recovery in a protocol that mimics clinical donor heart preservation.Hemagglutinating virus of Japan (HVJ)-liposome technique was used to transfect isolated rat hearts via intracoronary infusion of either the HSP70 gene (HSP group, n=16) or no gene (CON group, n=16), which was heterotopically transplanted into recipient rats. Four days after surgery, hearts were either perfused on a Langendorff apparatus for 30 minutes at 37 degrees C (preischemia studies [n=8/group]) or perfused for 30 minutes at 37 degrees C, cardioplegically arrested for 4 hours at 4 degrees C, and reperfused for 30 minutes at 37 degrees C (postischemia studies [n=8/group]). Western blotting and immunohistochemistry confirmed HSP70 upregulation in the HSP group. Postischemic mitochondrial respiratory control indices (RCIs) were significantly better preserved in HSP than in CON hearts: NAD(+)-linked RCI values were 9.54+/-1.1 versus 10.62+/-0.46 before ischemia (NS) but 7.98+/-0.69 versus 1.28+/-0.15 after ischemia (P<0.05), and FAD-linked RCI values were 6.87+/-0.88 versus 6.73+/-0.93 before ischemia (NS) but 4.26+/-0.41 versus 1.34+/-0.13 after ischemia (P<0.05). Postischemic recovery of mechanical function was greater in HSP than in CON hearts: left ventricular developed pressure recovery was 72.4+/-6.4% versus 59.7+/-5.3% (P<0.05), maximum dP/dt recovery was 77.9+/-6.6% versus 52.3+/-5.2% (P<0.05), and minimum dP/dt recovery was 72.4+/-7.2% versus 54.8+/-6.9% (P<0.05). Creatine kinase release in coronary effluent after reperfusion was 0.20+/-0.04 versus 0.34+/-0.06 IU. min(-1). g wet wt(-1) (P<0.05) in HSP versus in CON hearts.HSP70 upregulation protects mitochondrial function after ischemia-reperfusion injury; this was associated with improved preservation of ventricular function. Protection of mitochondrial function may be important in the development of future cardioprotective strategies.
Tree Pollen Allergoids in Pollinex Quattro Tree Immunotherapy Reduce the Residual Allergenicity as Assessed with Skin Prick Tests (SPTs)
Authors: M. Chudak, P. Patel, A. Salapatek, K. Jethwa, K.J. Fischer von Weikersthal-Drachenberg, J. Amersdorffer
Journal: Journal of Allergy and Clinical Immunology (2007)
HIF-1α and HIF-2α Are Differentially Regulated <i>In vivo</i> in Neuroblastoma: High HIF-1α Correlates Negatively to Advanced Clinical Stage and Tumor Vascularization
Authors: Rosa Noguera, Erik Fredlund, Marta Piqueras, Alexander Pietras, Siv Beckman, Samuel Navarro, Sven Påhlman
Journal: Clinical Cancer Research (2009)

Hypoxia is considered to be a major driving force behind tumor angiogenesis. The stabilization and activation at hypoxia of the hypoxia-inducible factors HIF-1alpha and HIF-2alpha and the concomitant induction of expression of vascular endothelial growth factor (VEGF) and other proangiogenic factors provide a molecular frame for hypoxia-driven tumor angiogenesis. This study has investigated how HIF and VEGF protein levels relate to each other with regard to vascularization, tumor stage, and overall survival in neuroblastoma.Tissue cores taken from tumor specimens representing 93 children with neuroblastoma were arranged on a microarray and stained for HIF-1alpha, HIF-2alpha, VEGF, and CD31 proteins. Both fraction of positive cells and staining intensity were evaluated and protein levels were correlated with each other and with clinical variables.Although high levels of both HIF-1alpha (P < 0.001) and HIF-2alpha (P < 0.001) correlated positively to VEGF expression, they did not fully correlate with each other. Moreover, HIF-1alpha (P = 0.002) and VEGF (P < 0.001), but not HIF-2alpha, correlated negatively to vascularization as determined by CD31 staining abundance. VEGF expression or degree of vascularization did not correlate with tumor stage or overall survival. High HIF-1alpha levels correlated with low tumor stage (P < 0.001) and were associated with a favorable patient prognosis (P = 0.08).The discordant results on expression of HIF-1alpha and HIF-2alpha suggest that these two proteins are differentially regulated in vivo, thus reflecting distinctive protein expression/stabilization mechanisms. The association between HIF-1alpha and favorable outcome stresses the importance of discriminating HIF-2alpha from HIF-1alpha expression and has implications for using HIFs as treatment targets.
Prediction of resistance development against drug combinations by collateral responses to component drugs
Authors: Christian Munck, Heidi K. Gumpert, Annika I. Nilsson Wallin, Harris H. Wang, Morten O. A. Sommer
Journal: Science Translational Medicine (2014)

Resistance arises quickly during chemotherapeutic selection and is particularly problematic during long-term treatment regimens such as those for tuberculosis, HIV infections, or cancer. Although drug combination therapy reduces the evolution of drug resistance, drug pairs vary in their ability to do so. Thus, predictive models are needed to rationally design resistance-limiting therapeutic regimens. Using adaptive evolution, we studied the resistance response of the common pathogen Escherichia coli to 5 different single antibiotics and all 10 different antibiotic drug pairs. By analyzing the genomes of all evolved E. coli lineages, we identified the mutational events that drive the differences in drug resistance levels and found that the degree of resistance development against drug combinations can be understood in terms of collateral sensitivity and resistance that occurred during adaptation to the component drugs. Then, using engineered E. coli strains, we confirmed that drug resistance mutations that imposed collateral sensitivity were suppressed in a drug pair growth environment. These results provide a framework for rationally selecting drug combinations that limit resistance evolution.
Identification of Axl as a downstream effector of TGF-β1 during Langerhans cell differentiation and epidermal homeostasis
Authors: Thomas Bauer, Anna Zagórska, Jennifer Jurkin, Nighat Yasmin, René Köffel, Susanne Richter, Bernhard Gesslbauer, Greg Lemke, Herbert Strobl
Journal: The Journal of Experimental Medicine (2012)

Transforming growth factor-β1 (TGF-β1) is a fundamental regulator of immune cell development and function. In this study, we investigated the effects of TGF-β1 on the differentiation of human Langerhans cells (LCs) and identified Axl as a key TGF-β1 effector. Axl belongs to the TAM (Tyro3, Axl, and Mer) receptor tyrosine kinase family, whose members function as inhibitors of innate inflammatory responses in dendritic cells and are essential to the prevention of lupus-like autoimmunity. We found that Axl expression is induced by TGF-β1 during LC differentiation and that LC precursors acquire Axl early during differentiation. We also describe prominent steady-state expression as well as inflammation-induced activation of Axl in human epidermal keratinocytes and LCs. TGF-β1–induced Axl enhances apoptotic cell (AC) uptake and blocks proinflammatory cytokine production. The antiinflammatory role of Axl in the skin is reflected in a marked impairment of the LC network preceding spontaneous skin inflammation in mutant mice that lack all three TAM receptors. Our findings highlight the importance of constitutive Axl expression to tolerogenic barrier immunity in the epidermis and define a mechanism by which TGF-β1 enables silent homeostatic clearing of ACs to maintain long-term self-tolerance.
CD32B, the human inhibitory Fc-γ receptor IIB, as a target for monoclonal antibody therapy of B-cell lymphoma
Authors: Christopher T. Rankin, Maria-Concetta Veri, Sergey Gorlatov, Nadine Tuaillon, Steve Burke, Ling Huang, H. David Inzunza, Hua Li, Shannon Thomas, Syd Johnson, Jeffrey Stavenhagen, Scott Koenig, Ezio Bonvini
Journal: Blood (2006)