99901
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Billich A, Bornancin F, Mechtcheriakova D, Natt F, Huesken D, Baumruker T. Basal and induced sphingosine kinase 1 activity in A549 carcinoma cells: function in cell survival and IL-1beta and TNF-alpha induced production of inflammatory mediators. Cell Signal 2005; 17:1203-17. [PMID: 16038795 DOI: 10.1016/j.cellsig.2004.12.005] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Accepted: 12/21/2004] [Indexed: 12/22/2022]
Abstract
Sphingosine-1-phosphate, a lipid mediator produced by sphingosine kinases, regulates diverse cellular processes, ranging from cell growth and survival to effector functions, such as proinflammatory mediator synthesis. Using human A549 epithelial lung carcinoma cells as a model system, we observed transient upregulation of sphingosine kinase type 1 (SPHK1) enzyme activity upon stimulation with both TNF-alpha or IL-1beta. This transient activation of SPHK1 was found to be required for cytokine-induced COX-2 transcription and PGE2 production, since not only specific siRNA (abolishing both basal and induced SPHK1 enzyme activity), but also a dominant-negative SPHK1 mutant (suppressing induced SPHK1 activity only) both reduced COX-2 and PGE2. Furthermore, TNF-alpha- or IL-1beta-induced transcription of selected cytokines, chemokines, and adhesion molecules (IL-6, RANTES, MCP-1, and VCAM-1) was found to require SPHK1 activation. Suppression of SPHK1 activation led to reduction of cytokine-induced IkappaBalpha phosphorylation and consequently diminished NFkappaB activity due to reduced nuclear translocation of RelA (p65), explaining the dependence of inflammatory mediator production on SPHK1 activation. Inhibition of basal SPHK1 activity by N,N-dimethylsphingosine or by downregulation of its expression using siRNA induced spontaneous apoptosis in A549 cells, an effect that can be explained through interference with constitutive NFkappaB activity in this cell type. In contrast, expression of the dominant-negative mutant did not induce apoptosis. Taken together, these findings demonstrate a role of SPHK1 activation in proinflammatory signalling and of SPHK1 basal activity in survival of A549 lung carcinoma cells.
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Affiliation(s)
- Andreas Billich
- Novartis Institutes for BioMedical Research, Brunnerstrasse 59, Vienna A-1235, Austria.
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99902
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Branger S, Rolain JM, Raoult D. Evaluation of antibiotic susceptibilities of Ehrlichia canis, Ehrlichia chaffeensis, and Anaplasma phagocytophilum by real-time PCR. Antimicrob Agents Chemother 2005; 48:4822-8. [PMID: 15561862 PMCID: PMC529244 DOI: 10.1128/aac.48.12.4822-4828.2004] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We determined MICs of antibiotics against Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Ehrlichia canis by real-time quantitative PCR. The doubling times of the organisms were established: 19 h for E. chaffeensis, 26 h for A. phagocytophilum, and 28 h for E. canis. In comparison to the reference method for determining sensitivities, which uses Diff-Quick staining, our PCR assay was very sensitive and specific. We confirmed that doxycycline and rifampin are highly active against these bacteria and found variable susceptibilities to fluoroquinolones; A. phagocytophilum was susceptible, but E. canis and E. chaffeensis were only partly susceptible. Beta-lactam compounds, cotrimoxazole, macrolide compounds, and telithromycin showed no activity against any of the three organisms. Thiamphenicol was found to be more active than chloramphenicol. For the first time, we showed that these three species have numerous point mutations in their 23S RNA genes, with those at positions 754, 2057, 2058, 2059, and 2611 (Escherichia coli numbering) known to confer resistance to macrolide compounds in other bacteria. The role of each of these mutations in resistance to these drugs should be investigated in the future. Our study confirms previous reports that quantitative PCR is a reliable method for determining antibiotic susceptibility; therefore, it might be useful for screening new drugs.
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Affiliation(s)
- S Branger
- Unité des Rickettsies, CNRS UMR 6020A, Faculté de Médecine, Marseille, France
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99903
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Liu CH, Chen YT, Wang PJ, Chin SC. Intestinal adenocarcinoma with pancreas and lymph node metastases in a captive cotton-top tamarin (Saguinus oedipus). J Vet Med Sci 2005; 66:1279-82. [PMID: 15528865 DOI: 10.1292/jvms.66.1279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A case of intestinal adenocarcinoma with metastases to the pancreas and regional lymph node was found in a 9-year-old, captive female cotton-top tamarin (Saguinus oedipus) with intermittent diarrhea. At necropsy, the tumor mass was located in the ileo-cecal junction causing circumferential thickening and annular stenosis. Microscopically, the lesions at primary and metastatic sites showed typical features of mucinous adenocarcinoma as seen in humans, including intracellular and extracellular mucin production and characteristic appearance of a signet ring of the tumor cells. The diagnosis was confirmed by histological evaluation, positive cytokeratin immunostain, and mucin production demonstrated by PAS and Alcian blue stain. It is speculated that the development of intestinal carcinoma was partly attributable to the excessive absorption of a diet of refined food, unbalanced nutrition, and the nature of these animals to develop stress easily.
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Affiliation(s)
- Chen-Hsuan Liu
- Graduate Institute of Veterinary Medicine, National Taiwan University, Japan
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99904
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Hemminki K, Försti A, Lorenzo Bermejo J. Single nucleotide polymorphisms (SNPs) are inherited from parents and they measure heritable events. J Carcinog 2005; 4:2. [PMID: 15652000 PMCID: PMC546222 DOI: 10.1186/1477-3163-4-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2004] [Accepted: 01/17/2005] [Indexed: 01/23/2023] Open
Abstract
Single nucleotide polymorphisms (SNPs) are extensively used in case-control studies of practically all cancer types. They are used for the identification of inherited cancer susceptibility genes and those that may interact with environmental factors. However, being genetic markers, they are applicable only on heritable conditions, which is often a neglected fact. Based on the data in the nationwide Swedish Family-Cancer Database, we review familial risks for all main cancers and discuss the evidence for a heritable component in cancer. The available evidence is not conclusive but it is consistent in pointing to a minor heritable etiology in cancer, which will hamper the success of SNP-based association studies. Empirical familial risks should be used as guidance for the planning of SNP studies. We provide calculations for the assessment of familial risks for assumed allele frequencies and gene effects (odds ratios) for different modes of inheritance. Based on these data, we discuss the gene effects that could account for the unexplained proportion of familial breast and lung cancer. As a conclusion, we are concerned about the indiscriminate use of a genetic tool to cancers, which are mainly environmental in origin. We consider the likelihood of a successful application of SNPs in gene-environment studies small, unless established environmental risk factors are tested on proven candidate genes.
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Affiliation(s)
- Kari Hemminki
- Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany
- Department of Biosciences at Novum, Karolinska Institute, 141 57 Huddinge, Sweden
| | - Asta Försti
- Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany
- Department of Biosciences at Novum, Karolinska Institute, 141 57 Huddinge, Sweden
| | - Justo Lorenzo Bermejo
- Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany
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99905
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Tiedemann K, Sasaki T, Gustafsson E, Göhring W, Bätge B, Notbohm H, Timpl R, Wedel T, Schlötzer-Schrehardt U, Reinhardt DP. Microfibrils at basement membrane zones interact with perlecan via fibrillin-1. J Biol Chem 2005; 280:11404-12. [PMID: 15657057 DOI: 10.1074/jbc.m409882200] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutational defects in fibrillin-rich microfibrils give rise to a number of heritable connective tissue disorders, generally termed microfibrillopathies. To understand the pathogenesis of these microfibrillopathies, it is important to elucidate the supramolecular composition of microfibrils and their interaction properties with extracellular matrix components. Here we demonstrate that the proteoglycan perlecan is an associated component of microfibrils typically close to basement membrane zones. Double immunofluorescence studies demonstrate colocalization of fibrillin-1, the major backbone component of microfibrils, with perlecan in fibroblast cultures as well as in dermal and ocular tissues. Double immunogold labeling further confirms colocalization of perlecan to microfibrils in various tissues at the ultrastructural level. Extraction studies revealed that perlecan is not covalently associated with microfibrils. High affinity interactions between fibrillin-1 and perlecan were found by kinetic binding studies with dissociation constants in the low nanomolar range. A detailed mapping study of the interaction epitopes by solid phase binding assays primarily revealed interactions of perlecan domains I and II with a central region of fibrillin-1. Analysis of perlecan null embryos showed less microfibrils at the dermal-epidermal junction as compared with wild-type littermates. The data presented indicate a functional significance for perlecan in anchoring microfibrils to basement membranes and in the biogenesis of microfibrils.
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Affiliation(s)
- Kerstin Tiedemann
- Department of Medical Molecular Biology, University of Lübeck, 23538 Lübeck, Germany
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99906
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Gloerich J, van Vlies N, Jansen GA, Denis S, Ruiter JPN, van Werkhoven MA, Duran M, Vaz FM, Wanders RJA, Ferdinandusse S. A phytol-enriched diet induces changes in fatty acid metabolism in mice both via PPARalpha-dependent and -independent pathways. J Lipid Res 2005; 46:716-26. [PMID: 15654129 DOI: 10.1194/jlr.m400337-jlr200] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Branched-chain fatty acids (such as phytanic and pristanic acid) are ligands for the nuclear hormone receptor peroxisome proliferator-activated receptor alpha (PPARalpha) in vitro. To investigate the effects of these physiological compounds in vivo, wild-type and PPARalpha-deficient (PPARalpha-/-) mice were fed a phytol-enriched diet. This resulted in increased plasma and liver levels of the phytol metabolites phytanic and pristanic acid. In wild-type mice, plasma fatty acid levels decreased after phytol feeding, whereas in PPARalpha-/- mice, the already elevated fatty acid levels increased. In addition, PPARalpha-/- mice were found to be carnitine deficient in both plasma and liver. Dietary phytol increased liver free carnitine in wild-type animals but not in PPARalpha-/- mice. Investigation of carnitine biosynthesis revealed that PPARalpha is likely involved in the regulation of carnitine homeostasis. Furthermore, phytol feeding resulted in a PPARalpha-dependent induction of various peroxisomal and mitochondrial beta-oxidation enzymes. In addition, a PPARalpha-independent induction of catalase, phytanoyl-CoA hydroxylase, carnitine octanoyltransferase, peroxisomal 3-ketoacyl-CoA thiolase, and straight-chain acyl-CoA oxidase was observed. In conclusion, branched-chain fatty acids are physiologically relevant ligands of PPARalpha in mice. These findings are especially relevant for disorders in which branched-chain fatty acids accumulate, such as Refsum disease and peroxisome biogenesis disorders.
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Affiliation(s)
- J Gloerich
- University of Amsterdam, Academic Medical Center, Departments of Clinical Chemistry and Pediatrics, Laboratory for Genetic Metabolic Diseases, 1100 DE Amsterdam, The Netherlands
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99907
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Calcium Sensing Receptor in Human Colon Carcinoma: Interaction with Ca2+ and 1,25-Dihydroxyvitamin D3. Cancer Res 2005. [DOI: 10.1158/0008-5472.493.65.2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Recent studies show that the human parathyroid calcium sensing receptor (CaSR) is expressed in human colon epithelium and functions to regulate epithelial proliferation and differentiation. In this study, we show that the cells of the colon crypt acquire CaSR expression as they differentiate and migrate towards the apex of the crypt. CaSR expression was weak in colon carcinomas with a more-differentiated histologic pattern, whereas CaSR expression was undetectable in less-differentiated tumors. We found that Ca2+ and/or 1,25(OH)2D3 stimulated CaSR promoter activity and CaSR protein expression in the human colon carcinoma CBS cells, which possessed a functional CaSR. Both agents concomitantly induced a series of changes in the CBS cells that influence proliferation and differentiation, but cellular responses to the two agents were not identical. Ca2+ strongly induced E-cadherin expression and inhibited the expression of the nuclear transcription factor, TCF4. 1,25(OH)2D3 was weaker in its effect on E-cadherin and was not able to inhibit TCF4 expression. 1,25(OH)2D3 was as strong or stronger than Ca2+ in its induction of the cyclin-dependent kinase inhibitors, P21 and p27. It is concluded that CaSR may function in the colon to regulate epithelial differentiation and that loss of CaSR expression may be associated with abnormal differentiation and/or malignant progression. Extracellular Ca2+ and 1,25(OH)2D3 are potential candidates involved in regulating CaSR expression in the colon and the chemopreventive actions of Ca2+ and 1,25(OH)2D3 in colon cancer may be mediated, in part, through the CaSR.
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99908
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Guidoboni M, Zancai P, Cariati R, Rizzo S, Dal Col J, Pavan A, Gloghini A, Spina M, Cuneo A, Pomponi F, Bononi A, Doglioni C, Maestro R, Carbone A, Boiocchi M, Dolcetti R. Retinoic Acid Inhibits the Proliferative Response Induced by CD40 Activation and Interleukin-4 in Mantle Cell Lymphoma. Cancer Res 2005. [DOI: 10.1158/0008-5472.587.65.2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Mantle cell lymphoma (MCL) is an aggressive B-cell non-Hodgkin's lymphoma with poor response to therapy and unfavorable prognosis. Here, we show that retinoic acid (RA) isomers significantly inhibit the proliferation of both primary MCL cultures (n = 7) and established cell lines (Granta 519 and SP-53) as shown by [3H]thymidine uptake and carboxyfluorescein diacetate succinimidyl ester labeling coupled with cyclin D1 staining. RA induces cell accumulation in G0-G1 together with a marked up-regulation of p27Kip1 by inhibiting ubiquitination and proteasome-dependent degradation of the protein. The p21Cip1 inhibitor was also up-regulated by RA in Granta 519 cells, whereas the expression of cyclin D1 is unaffected. Most of RA-induced p27Kip1 was bound to cyclin D1/cyclin-dependent kinase 4 complexes, probably contributing to the decreased cyclin-dependent kinase 4 kinase activity and pRb hypophosphorylation observed in RA-treated cells. Experiments with receptor-selective ligands indicate that RA receptor α cooperates with retinoid X receptors in mediating RA-dependent MCL cell growth inhibition. Notably, RA isomers, and particularly 9-cis-RA, also inhibited the growth-promoting effect induced in primary MCL cells by CD40 activation alone or in combination with interleukin-4. Immunohistochemical analysis showed that significant numbers of CD40L-expressing lymphoid cells are present in lymph node biopsies of MCL patients. These results therefore further strengthen the possibility that triggering of CD40 by infiltrating CD40L+ cells may continuously promote the growth of MCL cells in vivo. On these grounds, our findings that RA inhibits basal MCL proliferation as well as MCL growth-promoting effects exerted by microenvironmental factors make these compounds highly attractive in terms of potential clinical efficacy in this setting.
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Affiliation(s)
| | | | | | | | | | | | | | - Michele Spina
- 4Division of Medical Oncology A, Centro di Riferimento Oncologico, IRCCS-National Cancer Institute, Aviano, Italy
| | - Antonio Cuneo
- 5Hematology Section, Department of Biomedical Sciences and Advanced Therapies, University of Ferrara
| | | | - Antonio Bononi
- 7Division of Medical Oncology, General Hospital, Rovigo, Italy; and
| | - Claudio Doglioni
- 8Division of Pathology, San Raffaele H Scientific Institute, Milan, Italy
| | - Roberta Maestro
- 2Division of Experimental Oncology 1, Department of Pre-clinical and Epidemiological Research
| | | | - Mauro Boiocchi
- 2Division of Experimental Oncology 1, Department of Pre-clinical and Epidemiological Research
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99909
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Abraham RS, Ballman KV, Dispenzieri A, Grill DE, Manske MK, Price-Troska TL, Paz NG, Gertz MA, Fonseca R. Functional gene expression analysis of clonal plasma cells identifies a unique molecular profile for light chain amyloidosis. Blood 2005; 105:794-803. [PMID: 15388584 DOI: 10.1182/blood-2004-04-1424] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractImmunoglobulin light chain amyloidosis (AL) is characterized by a clonal expansion of plasma cells within the bone marrow. Gene expression analysis was used to identify a unique molecular profile for AL using enriched plasma cells (CD138+) from the bone marrow of 24 patients with AL and 28 patients with multiple myeloma (MM) and 6 healthy controls. Class prediction analysis (PAM) revealed a subset of 12 genes, which included TNFRSF7 (CD27), SDF-1, and PSMA2, that distinguished between these 2 groups with an estimated and observed accuracy of classification of 92%. This model was validated with an independent dataset of 11 patients with AL and 12 patients with MM with 87% accuracy. Differential expression for the most discriminant genes in the 12-gene subset was validated using quantitative real-time polymerase chain reaction and protein expression analysis, which upheld the observations from the micro-array expression data. Functional analyses using a novel network mapping software revealed a number of potentially significant pathways that were dysregulated in patients with AL, with those regulating proliferation, apoptosis, cell signaling, chemotaxis, and migration being substantially represented. This study provides new insight into the molecular profile of clonal plasma cells and its functional relevance in the pathogenesis of light chain amyloidosis.
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Affiliation(s)
- Roshini S Abraham
- Division of Hematology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
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99910
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Kishimoto M, Kohno T, Okudela K, Otsuka A, Sasaki H, Tanabe C, Sakiyama T, Hirama C, Kitabayashi I, Minna JD, Takenoshita S, Yokota J. Mutations and Deletions of the CBP Gene in Human Lung Cancer. Clin Cancer Res 2005. [DOI: 10.1158/1078-0432.512.11.2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: Microarray-based comparative genomic hybridization analysis led us to detect a homozygous deletion at the cyclic AMP response element binding protein-binding protein (CBP) locus in a lung cancer cell line. Oncogenic roles of CBP had been suggested by functional and genetic studies; thus, involvement of CBP gene alterations in lung carcinogenesis was investigated by undertaking comprehensive analysis of genetic CBP alterations in human lung cancer.
Experimental Design: Fifty-nine cell lines and 95 surgical specimens of lung cancer were analyzed for mutations, homozygous and hemizygous deletions, and expression of the CBP gene.
Results: Homozygous CBP deletions, including two intragenic deletions, were detected in three (5.1%) lung cancer cell lines. CBP mutations, including missense, nonsense, and frame-shift mutations, were detected in six (10.2 %) cell lines and five (5.3%) surgical specimens of lung cancer. The wild-type CBP allele was retained in 9 of 11 cases with CBP mutations, and both the wild-type and mutant alleles were expressed in all the six cases with heterozygous CBP mutations examined. Three mutations with amino acid substitutions in the histone acetyltransferase domain caused significant reduction in transcription activation activity of CBP protein in vivo.
Conclusions: A fraction of lung cancers carried mutations and/or deletions of the CBP gene, suggesting that genetic CBP alterations are involved in the genesis and/or progression of a subset of lung cancers.
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Affiliation(s)
- Masahiro Kishimoto
- 1Biology Division,
- 5Second Department of Surgery, Fukushima Medical University School of Medicine, Fukushima, Japan; and
| | | | | | | | - Hiroki Sasaki
- 2Center for Medical Genomics,
- 3Genetics Division, and
| | | | | | | | - Issay Kitabayashi
- 4Molecular Oncology Division, National Cancer Center Research Institute, Tokyo, Japan
| | - John D. Minna
- 6Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Seiichi Takenoshita
- 5Second Department of Surgery, Fukushima Medical University School of Medicine, Fukushima, Japan; and
| | - Jun Yokota
- 1Biology Division,
- 2Center for Medical Genomics,
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99911
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Han GZ, Liu ZJ, Shimoi K, Zhu BT. Synergism between the Anticancer Actions of 2-Methoxyestradiol and Microtubule-Disrupting Agents in Human Breast Cancer. Cancer Res 2005. [DOI: 10.1158/0008-5472.387.65.2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
2-Methoxyestradiol (2-MeO-E2), a well-known nonpolar endogenous metabolite of 17β-estradiol, has strong antiproliferative, apoptotic, and antiangiogenic actions in vitro and in vivo at pharmacologic concentrations. We determined in the present study whether 2-MeO-E2 can enhance the anticancer actions of paclitaxel or vinorelbine (two commonly used microtubule-disrupting agents) in several human breast cancer cell lines, including the estrogen receptor–positive MCF-7 and T-47D cells and the receptor-negative MDA-MB-435s and MDA-MB-231 cells. 2-MeO-E2 in combination with paclitaxel or vinorelbine exhibited a synergistic anticancer effect in these human breast cancer cells in vitro, and this synergistic effect was more pronounced when each of the drugs was used at relatively low concentrations. Additional experiments using female athymic BALB/c nu/nu mice showed that p.o. administration of 2-MeO-E2 at 30 mg/kg body weight, once a week for 6 weeks, markedly enhanced the activity of paclitaxel or vinorelbine against the growth of the estrogen receptor–negative MDA-MB-231 human breast cancer xenografts in these animals. By contrast, combination of 2-MeO-E2 with 5-fluorouracil only had a partial additive effect against the growth of these cell lines in culture, and no synergistic effect was observed. Interestingly, when doxorubicin was used in combination with 2-MeO-E2, the antiproliferative effect of 2-MeO-E2 was somewhat antagonized by doxorubicin when it was present at high concentrations. Our results showed that 2-MeO-E2 at nontoxic or subtoxic doses selectively enhanced the effects of certain microtubule-disrupting agents (such as paclitaxel and vinorelbine) against the growth of the receptor-negative human breast cancer cells in culture and also in athymic nude mice.
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Affiliation(s)
- Gui-Zhen Han
- 1Department of Basic Pharmaceutical Sciences, College of Pharmacy, University of South Carolina, Columbia, South Carolina and
| | - Zhi-Jian Liu
- 1Department of Basic Pharmaceutical Sciences, College of Pharmacy, University of South Carolina, Columbia, South Carolina and
| | - Kayoko Shimoi
- 2Institute for Environmental Sciences, University of Shizuoka, Shizuoka, Japan
| | - Bao Ting Zhu
- 1Department of Basic Pharmaceutical Sciences, College of Pharmacy, University of South Carolina, Columbia, South Carolina and
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99912
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Dewan MZ, Terashima K, Ahmed S, Ohba K, Taruishi M, Yamamoto N. Mouse serum factor(s) down-modulate the CD4 and CXCR4 molecules on human T cells conferring resistance to HIV infection in NOG mice. Med Microbiol Immunol 2005; 194:175-80. [PMID: 15654627 DOI: 10.1007/s00430-004-0234-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2004] [Indexed: 10/25/2022]
Abstract
Human cells have developed innate immunity, exploiting several means to block virus infection, and viruses have evolved diverse strategies to resist these. We show here that the human immunodeficiency virus 1 (HIV-1) could neither progressively infect engrafted human leukemic T cells nor repress their growth in NOG mice. However, ED-40515(-) cells infected with HIV-1 before inoculation were found to significantly delay the onset of tumor growth and increased the survival period of NOG mice. ED-40515(-) tumor cells showed resistance to HIV-1 which was apparently correlated with the down-regulation of CD4 and CXCR4 molecules in NOG mice. Serum from three different mouse strains, including NOG, retained a suppressive effect on the CD4 molecule of ED-40515(-) cells in vitro. ED-40515(-) cells obtained from mice re-expressed CD4 and CXCR4 molecules upon in vitro culture and were again successfully infected with HIV-1. These findings indicate that HIV-1 may initially successfully delay or regress tumor growth in NOG mice, but eventually fails to do so because of the evolution of HIV-resistant cells due to a rapid down-modulation of CD4 and CXCR4. Our data also demonstrated that some unknown soluble factor(s) present in mouse serum was responsible for conferring resistance to HIV infection to human T cells.
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Affiliation(s)
- Md Zahidunnabi Dewan
- Department of Molecular Virology, Bio-Response, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Tokyo 113-8519, Japan
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99913
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Huang DS, Shen KZ, Wei JF, Liang TB, Zheng SS, Xie HY. Specific COX-2 inhibitor NS398 induces apoptosis in human liver cancer cell line HepG2 through BCL-2. World J Gastroenterol 2005; 11:204-7. [PMID: 15633216 PMCID: PMC4205402 DOI: 10.3748/wjg.v11.i2.204] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To evaluate the effects of NS-398, a cyclooxygenase-2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells.
METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells. DNA ploidy and apoptotic cell percentage were calculated by flow cytometry. The expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. Furthermore, expression level of Bcl-2 was detected using Western blot in HepG2 after treated with NS-398.
RESULTS: NS-398 inhibited cell proliferation and induced apoptosis of HepG2 cells in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with increase of NS-398 concentration. The quiescent G0/G1 phase was accumulated with decrease of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, and no correlations were found between COX-2 mRNA and HepG2 cell proliferation and apoptosis induced by NS-398 (r = 0.056 and r = 0.119, respectively). Bcl-2 protein level was inhibited after treated with NS-398.
CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis of HepG2 cells. Mechanisms involved may be accumulation of quiescent G0/G1 phase and decrease of Bcl-2 expression.
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Affiliation(s)
- Dong-Sheng Huang
- Department of Hepatobiliary Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University, College of Medicine, Hangzhou 310003, Zhejiang Province, China
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99914
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Metzler B, Gfeller P, Bigaud M, Li J, Wieczorek G, Heusser C, Lake P, Katopodis A. Combinations of anti-LFA-1, everolimus, anti-CD40 ligand, and allogeneic bone marrow induce central transplantation tolerance through hemopoietic chimerism, including protection from chronic heart allograft rejection. THE JOURNAL OF IMMUNOLOGY 2005; 173:7025-36. [PMID: 15557200 DOI: 10.4049/jimmunol.173.11.7025] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Central transplantation tolerance through hemopoietic chimerism initially requires inhibition of allogeneic stem cell or bone marrow (BM) rejection, as previously achieved in murine models by combinations of T cell costimulation blockade. We have evaluated LFA-1 blockade as part of regimens to support mixed hemopoietic chimerism development upon fully allogeneic BALB/c BM transfer to nonirradiated busulfan-treated B6 recipient mice. Combining anti-LFA-1 with anti-CD40 ligand (CD40L) induced high incidences and levels of stable multilineage hemopoietic chimerism comparable to chimerism achieved with anti-CD40L and everolimus (40-O-(2-hydroxyethyl)-rapamycin) under conditions where neither Ab alone was effective. The combination of anti-LFA-1 with everolimus also resulted in high levels of chimerism, albeit with a lower incidence of stability. Inhibition of acute allograft rejection critically depended on chimerism stability, even if maintained at very low levels around 1%, as was the case for some recipients without busulfan conditioning. Chimerism stability correlated with a significant donor BM-dependent loss of host-derived Vbeta11(+) T cells 3 mo after BM transplantation (Tx). Combinations of anti-CD40L with anti-LFA-1 or everolimus also prevented acute rejection of skin allografts transplanted before established chimerism, albeit not independently of allospecific BMTx. All skin and heart allografts transplanted to stable chimeras 3 and 5 mo after BMTx, respectively, were protected from acute rejection. Moreover, this included prevention of heart allograft vascular intimal thickening ("chronic rejection").
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Affiliation(s)
- Barbara Metzler
- Autoimmunity and Transplantation, Novartis Institutes for Biomedical Research, Basel, Switzerland.
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99915
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Yang G, Shu XO, Ruan ZX, Cai QY, Jin F, Gao YT, Zheng W. Genetic polymorphisms in glutathione-S-transferase genes (GSTM1, GSTT1, GSTP1) and survival after chemotherapy for invasive breast carcinoma. Cancer 2005; 103:52-8. [PMID: 15565566 DOI: 10.1002/cncr.20729] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND It has been suggested that genetic polymorphisms in certain glutathione-S-transferase (GST) genes reduce the effectiveness of detoxifying cytotoxins generated by chemotherapeutic agents, potentially resulting in enhanced clinical responses to chemotherapy. METHODS The authors evaluated common polymorphisms in the GSTM1, GSTT1, and GSTP1 genes for associations with overall survival in 1034 patients with invasive breast carcinoma who were recruited into the Shanghai Breast Cancer Study between 1996 and 1998, treated with chemotherapy, and followed for a median of 5.3 years. RESULTS After adjusting for age, tumor stage, and the use of radiotherapy and tamoxifen, women who were homozygous for the variant GSTP1 105Val allele had a 60% reduction in mortality risk compared with women who were homozygous for the Ile allele (hazard ratio, 0.4; 95% confidence interval, 0.2-0.8). No association was found with respect to any of the GSTM1 or GSTT1 genotypes. CONCLUSIONS The results of the current study indicate a potential role for GSTP1 polymorphism in predicting the clinical outcomes of patients with breast carcinoma who are treated with chemotherapy.
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Affiliation(s)
- Gong Yang
- Vanderbilt Center for Health Services Research, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-8300, USA.
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99916
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Jennings P, Bertocchi C, Frick M, Haller T, Pfaller W, Dietl P. Ca 2+ Induced Surfactant Secretion in Alveolar Type II Cultures Isolated from the H-2K b-tsA58 Transgenic Mouse. Cell Physiol Biochem 2005; 15:159-66. [PMID: 15665525 DOI: 10.1159/000083648] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2004] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS There is a need for the development of transgenic mice to elucidate molecular mechanisms in surfactant secretion. However at present very little is known about the regulation of surfactant exocytosis in murine alveolar type II (AT II) cells. METHODS We brought AT II cells isolated from the Immorto mouse into culture at 33 degrees C, in the presence of interferon, to generate immortal mouse AT II cells (iMAT II). Surfactant secretion was measured using real-time fluorescence imaging. RESULTS iMAT II cells stained with lysotracker green (LTG), a dye specific for lamellar body related vesicles in rat AT II cells. Expression of densely layered structures, characteristic of LBs, was confirmed by transmission electron microscopy. Flash photolysis of caged Ca2+, which specifically elevates intracellular Ca2+ concentration ([Ca2+]i), resulted in LB fusion to the plasma membrane, as analysed using the lipid staining dye FM 1-43. Purinergic stimulation with ATP (10 microM), also resulted in a rise in [Ca2+]i (measured by fura-2), which was followed by LB fusion. CONCLUSIONS iMATII cells maintain the expression of LBs over several passages. Surfactant secretion in these cells is regulated by [Ca2+]i, and exhibits similar characteristics to that of rat AT II cells. These cells will be beneficial in studying the impact of genetic modifications on regulated surfactant secretion.
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Affiliation(s)
- Paul Jennings
- Department of Physiology, Innsbruck Medical University, Innsbruck, Austria.
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99917
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Nakahara T, Nakamura T, Kobayashi E, Kuremoto KI, Matsuno T, Tabata Y, Eto K, Shimizu Y. In situ tissue engineering of periodontal tissues by seeding with periodontal ligament-derived cells. ACTA ACUST UNITED AC 2005; 10:537-44. [PMID: 15165470 DOI: 10.1089/107632704323061898] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The feasibility of an in situ tissue-engineering method employing cell-based therapy with autologous periodontal ligament-derived cells was investigated. Periodontal ligament cells were obtained from six beagle dogs. Periodontal fenestration defects (6 x 4 mm) were created bilaterally at a location 6 mm apical to the marginal alveolar crest in the maxillary canines. Alkaline phosphatase-positive periodontal ligament cells (3 x 10(5) cells) were seeded onto a collagen sponge scaffold just before implantation. One defect was filled with the cell-scaffold construct, and another was left empty as the control. All animals were killed 4 weeks after surgery, and specimens were evaluated histomorphometrically. All the histomorphometrical data were analyzed by three-way analysis of variance with the Bonferroni multiple comparisons test. Regeneration of apical tissue was faster than that of coronal and isolated tissues on the control side (apical > coronal > isolated; p < 0.0001). On the other hand, on the cell-seeded side, regeneration of the cementum was observed uniformly on the root surface. Our data suggest that the seeded cells induced cementum regeneration on the root surface, indicating the potential of in situ tissue engineering using autologous cells for the regeneration of periodontal tissues.
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Affiliation(s)
- Taka Nakahara
- Section of Molecular Craniofacial Embryology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
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99918
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Chan CHF, Stanners CP. Novel mouse model for carcinoembryonic antigen-based therapy. Mol Ther 2005; 9:775-85. [PMID: 15194045 DOI: 10.1016/j.ymthe.2004.03.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Accepted: 03/11/2004] [Indexed: 12/22/2022] Open
Abstract
Many novel cancer therapies, including immunotherapy and gene therapy, are specifically targeted to tumor-associated molecules, among which carcinoembryonic antigen (CEA) represents a popular example. Discrepancies between preclinical experimental data in animal models and clinical outcome in terms of therapeutic response and toxicity, however, often arise. Preclinical testing can be compromised by the lack of CEA and other closely related human CEA family members in rodents, which lack analogous genes for most human CEA family members. Here, we report the construction of a transgenic mouse with a 187-kb human bacterial artificial chromosome (CEABAC) that contains part of the human CEA family gene cluster including complete human CEA (CEACAM5), CEACAM3, CEACAM6, and CEACAM7 genes. The spatiotemporal expression pattern of these genes in the CEABAC mice was found to be remarkably similar to that of humans. This novel mouse will ensure better assessment than previously utilized models for the preclinical testing of CEA-targeted therapies and perhaps allow the testing of CEACAM6, which is overexpressed in many solid tumors and leukemias, as a therapeutic target. Moreover, expression of CEA family genes in gastrointestinal, breast, hematopoietic, urogenital, and respiratory systems could facilitate other clinical applications, such as the development of therapeutic agents against Neisseria gonorrhoeae infections, which use CEA family members as major receptors.
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Affiliation(s)
- Carlos H F Chan
- Department of Biochemistry and McGill Cancer Centre, McGill University, Montreal, Quebec, Canada H3G 1Y6
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99919
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Aukrust P, Yndestad A, Damås JK, Gullestad L. Inflammation and chronic heart failure-potential therapeutic role of intravenous immunoglobulin. Autoimmun Rev 2005; 3:221-7. [PMID: 15110235 DOI: 10.1016/s1568-9972(03)00103-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2003] [Accepted: 07/29/2003] [Indexed: 11/29/2022]
Abstract
Accumulating evidence indicates that inflammatory cytokines play a pathogenic role in congestive heart failure (CHF) by influencing heart contractility, inducing hypertrophy and promoting apoptosis or fibrosis, contributing to the continuous myocardial remodelling process. Traditional cardiovascular drugs seem to have little influence on the overall cytokine network, and immunomodulatory therapy have emerged as a possible new treatment modality in CHF. Several animal studies have suggested that modulation of inflammatory cytokines may improve cardiac performance, and we have recently demonstrated that intravenous immunoglobulin enhances left ventricular ejection fraction in CHF patients, significantly correlated with anti-inflammatory effects of such therapy. While not necessarily the drugs of choice, these studies suggest a potential for immunomodulatory therapy in CHF in addition to optimal cardiovascular treatment regimens. Further research will have to more precisely identify the most important actors in the immunopathogenesis of CHF in order to develop more specific immunomodulating agents in this disorder. Although these shortcomings, we believe that the 'cytokine era' in cardiovascular research might lead to quite new treatment modalities in CHF patients potentially leading to reduced morbidity and mortality in these patients.
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Affiliation(s)
- Pål Aukrust
- Research Institute for Internal Medicine, Rikshospitalet, University of Oslo, Norway.
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99920
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Soares ML, Coelho T, Sousa A, Batalov S, Conceição I, Sales-Luís ML, Ritchie MD, Williams SM, Nievergelt CM, Schork NJ, Saraiva MJ, Buxbaum JN. Susceptibility and modifier genes in Portuguese transthyretin V30M amyloid polyneuropathy: complexity in a single-gene disease. Hum Mol Genet 2005; 14:543-53. [PMID: 15649951 DOI: 10.1093/hmg/ddi051] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Familial amyloid polyneuropathy type I is an autosomal dominant disorder caused by mutations in the transthyretin (TTR) gene; however, carriers of the same mutation exhibit variability in penetrance and clinical expression. We analyzed alleles of candidate genes encoding non-fibrillar components of TTR amyloid deposits and a molecule metabolically interacting with TTR [retinol-binding protein (RBP)], for possible associations with age of disease onset and/or susceptibility in a Portuguese population sample with the TTR V30M mutation and unrelated controls. We show that the V30M carriers represent a distinct subset of the Portuguese population. Estimates of genetic distance indicated that the controls and the classical-onset group were furthest apart, whereas the late-onset group appeared to differ from both. Importantly, the data also indicate that genetic interactions among the multiple loci evaluated, rather than single-locus effects, are more likely to determine differences in the age of disease onset. Multifactor dimensionality reduction indicated that the best genetic model for classical onset group versus controls involved the APCS gene, whereas for late-onset cases, one APCS variant (APCSv1) and two RBP variants (RBPv1 and RBPv2) are involved. Thus, although the TTR V30M mutation is required for the disease in Portuguese patients, different genetic factors may govern the age of onset, as well as the occurrence of anticipation.
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Affiliation(s)
- Miguel L Soares
- Department of Molecular and Experimental Medicine, Division of Rheumatology Research and the WM Keck Autoimmune Disease Center, The Scripps Research Institute, La Jolla, CA 92037, USA
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99921
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Singh Y, Defrancq E, Dumy P. New method to prepare peptide-oligonucleotide conjugates through glyoxylic oxime formation. J Org Chem 2005; 69:8544-6. [PMID: 15549841 DOI: 10.1021/jo0485177] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new method to prepare peptide-oligonucleotide conjugates through chemoselective glyoxylic oxime linkage is reported. A novel phosphoramidite reagent, readily accessible from serine, was prepared and used in automated DNA synthesis to prepare oligonucleotides carrying a glyoxylic aldehyde functionality at the 5' terminus. This was efficiently coupled to a peptide functionalized with an aminooxy group. The method could be of general use to prepare a broad range of oligonucleotide conjugates.
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Affiliation(s)
- Yashveer Singh
- LEDSS, UMR CNRS 5616, ICMG FR2607, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 9, France
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99922
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Marcus AI, Peters U, Thomas SL, Garrett S, Zelnak A, Kapoor TM, Giannakakou P. Mitotic kinesin inhibitors induce mitotic arrest and cell death in Taxol-resistant and -sensitive cancer cells. J Biol Chem 2005; 280:11569-77. [PMID: 15653676 PMCID: PMC1861807 DOI: 10.1074/jbc.m413471200] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Taxanes are powerful chemotherapy agents that target the microtubule cytoskeleton, leading to mitotic arrest and cell death; however, their clinical efficacy has been hampered due to the development of drug resistance. Therefore, other proteins involved in spindle assembly are being examined as potential targets for anticancer therapy. The mitotic kinesin, Eg5 is critical for proper spindle assembly; as such, inhibition of Eg5 leads to mitotic arrest making it a potential anticancer target. We wanted to validate Eg5 as a therapeutic target and determine if Eg5 inhibitors retain activity in Taxol-resistant cells. Using affinity chromatography we first show that the compound HR22C16 is an Eg5 inhibitor and does not interact with other microtubule motor proteins tested. Furthermore, HR22C16 along with its analogs, inhibit cell survival in both Taxol-sensitive and -resistant ovarian cancer cells with at least 15-fold greater efficacy than monastrol, the first generation Eg5 inhibitor. Further analysis with HR22C16-A1, the most potent HR22C16 analog, showed that it retains efficacy in PgP-overexpressing cells, suggesting that it is not a PgP substrate. We further show that HR22C16-A1 induces cell death following mitotic arrest via the intrinsic apoptotic pathway. Interestingly, the combination of HR22C16-A1 with Taxol results in an antagonistic antiproliferative and antimitotic effect, possibly due to the abrogation of Taxol-induced mitotic spindles by HR22C16-A1. Taken together, our results show that Eg5 inhibitors have promising anticancer activity and can be potentially used to overcome Taxol resistance in the clinical setting.
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Affiliation(s)
- Adam I. Marcus
- From the Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Ulf Peters
- Laboratory of Chemistry and Cell Biology, Rockefeller University, New York, New York 10021
| | - Shala L. Thomas
- From the Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Sarah Garrett
- Laboratory of Chemistry and Cell Biology, Rockefeller University, New York, New York 10021
| | - Amelia Zelnak
- From the Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Tarun M. Kapoor
- Laboratory of Chemistry and Cell Biology, Rockefeller University, New York, New York 10021
| | - Paraskevi Giannakakou
- From the Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia 30322
- ¶To whom correspondence should be addressed. E-mail:
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99923
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Matarrese P, Straface E, Pietraforte D, Gambardella L, Vona R, Maccaglia A, Minetti M, Malorni W. Peroxynitrite induces senescence and apoptosis of red blood cells through the activation of aspartyl and cysteinyl proteases. FASEB J 2005; 19:416-8. [PMID: 15650007 DOI: 10.1096/fj.04-2450fje] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Changes in the oxidative status of erythrocytes can reduce cell lifetime, oxygen transport, and delivery capacity to peripheral tissues and have been associated with a plethora of human diseases. Among reactive oxygen and nitrogen species of importance in red blood cell (RBC) homeostasis, superoxide and nitric oxide radicals play a key role. In the present work, we evaluated subcellular effects induced by peroxynitrite, the product of the fast reaction between superoxide and nitric oxide. Peroxynitrite induced 1) oxidation of oxyhemoglobin to methemoglobin, 2) cytoskeleton rearrangement, 3) ultrastructural alterations, and 4) altered expression of band-3 and decreased expression of glycophorin A. With respect to control cells, this occurred in a significantly higher percentage of human RBC (approximately 40%). The presence of antioxidants inhibited these modifications. Furthermore, besides these senescence-associated changes, other important modifications, absent in control RBC and usually associated with apoptotic cell death, were detected in a small but significant subset of peroxynitrite-exposed RBC (approximately 7%). Active protease cathepsin E and mu-calpain increased; activation of caspase 2 and caspase 3 was detected; and phosphatidylserine externalization, an early marker of apoptosis, was observed. Conversely, inhibition of cathepsin E, mu-calpain, as well as caspase 2 and 3 by specific inhibitors resulted in a significant impairment of erythrocyte "apoptosis" Altogether, these results indicate that peroxynitrite, a milestone of redox-mediated damage in human pathology, can hijack human RBC toward senescence and apoptosis by a mechanism involving both cysteinyl and aspartyl proteases.
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Affiliation(s)
- Paola Matarrese
- Department of Drug Research and Evaluation, Istituto Superiore di Sanita, Rome 00161, Italy
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99924
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Al-Awwadi NA, Araiz C, Bornet A, Delbosc S, Cristol JP, Linck N, Azay J, Teissedre PL, Cros G. Extracts enriched in different polyphenolic families normalize increased cardiac NADPH oxidase expression while having differential effects on insulin resistance, hypertension, and cardiac hypertrophy in high-fructose-fed rats. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:151-157. [PMID: 15631522 DOI: 10.1021/jf048919f] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Insulin resistance and oxidative stress act synergistically in the development of cardiovascular complications. The present study compared the efficacy of three polyphenolic extracts in their capacity to prevent hypertension, cardiac hypertrophy, increased production of reactive oxygen species (ROS) by the aorta or the heart, and increased expression of cardiac NAD(P)H oxidase in a model of insulin resistance. Rats were fed a 60%-enriched fructose food and were treated once a day (gavage) for 6 weeks with 10 mL/kg of water only (F group) or the same amount of solution containing a red grape skin polyphenolic extract enriched in anthocyanins (ANT), a grape seed extract enriched in procyanidins and rich in galloylated procyanidins (PRO), or the commercial preparation Vitaflavan (VIT), rich in catechin oligomers. All treatments were administered at the same dose of 21 mg/kg of polyphenols. Our data indicate that (a) the ANT treatment prevented hypertension, cardiac hypertrophy, and production of ROS, (b) the PRO treatment prevented insulin resistance, hypertriglyceridemia, and overproduction of ROS but had only minor effects on hypertension or hypertrophy, while (c) Vitaflavan prevented hypertension, cardiac hypertrophy, and overproduction of ROS. All polyphenolic treatments prevented the increased expression of the p91phox NADPH oxidase subunit. In summary, our study suggest that (a) the pathogeny of cardiac hypertrophy in the fructose-fed rat disease involves both hypertension and hyperproduction of ROS, (b) polyphenolic extracts enriched in different types of polyphenols possess differential effects on insulin resistance, hypertension, and cardiac hypertrophy, and (c) polyphenols modulate the expression of NAD(P)H oxidase.
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Affiliation(s)
- Najim A Al-Awwadi
- Laboratoire de Pharmacologie et Physiopathologie Expérimentales, INSERM U376, 15 Av. Charles Flahault, B.P. 14491, 34093 Montpellier 5, France
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99925
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Clifton DR, Rydkina E, Freeman RS, Sahni SK. NF-kappaB activation during Rickettsia rickettsii infection of endothelial cells involves the activation of catalytic IkappaB kinases IKKalpha and IKKbeta and phosphorylation-proteolysis of the inhibitor protein IkappaBalpha. Infect Immun 2005; 73:155-65. [PMID: 15618150 PMCID: PMC538953 DOI: 10.1128/iai.73.1.155-165.2005] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rocky Mountain spotted fever, a systemic tick-borne illness caused by the obligate intracellular bacterium Rickettsia rickettsii, is associated with widespread infection of the vascular endothelium. R. rickettsii infection induces a biphasic pattern of the nuclear factor-kappaB (NF-kappaB) activation in cultured human endothelial cells (ECs), characterized by an early transient phase at 3 h and a late sustained phase evident at 18 to 24 h. To elucidate the underlying mechanisms, we investigated the expression of NF-kappaB subunits, p65 and p50, and IkappaB proteins, IkappaBalpha and IkappaBbeta. The transcript and protein levels of p50, p65, and IkappaBbeta remained relatively unchanged during the course of infection, but Ser-32 phosphorylation of IkappaBalpha at 3 h was significantly increased over the basal level in uninfected cells concomitant with a significant increase in the expression of IkappaBalpha mRNA. The level of IkappaBalpha mRNA gradually returned toward baseline, whereas that of total IkappaBalpha protein remained lower than the corresponding controls. The activities of IKKalpha and IKKbeta, the catalytic subunits of IkappaB kinase (IKK) complex, as measured by in vitro kinase assays with immunoprecipitates from uninfected and R. rickettsii-infected ECs, revealed significant increases at 2 h after infection. The activation of IKK and early phase of NF-kappaB response were inhibited by heat treatment and completely abolished by formalin fixation of rickettsiae. The IKK inhibitors parthenolide and aspirin blocked the activities of infection-induced IKKalpha and IKKbeta, leading to attenuation of nuclear translocation of NF-kappaB. Also, increased activity of IKKalpha was evident later during the infection, coinciding with the late phase of NF-kappaB activation. Thus, activation of catalytic components of the IKK complex represents an important upstream signaling event in the pathway for R. rickettsii-induced NF-kappaB activation. Since NF-kappaB is a critical regulator of inflammatory genes and prevents host cell death during infection via antiapoptotic functions, selective inhibition of IKK may provide a potential target for enhanced clearance of rickettsiae and an effective strategy to reduce inflammatory damage to the host during rickettsial infections.
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Affiliation(s)
- Dawn R Clifton
- Hemostasis and Thrombosis Program, Hematology-Oncology Unit, Department of Medicine, P.O. Box 610, University of Rochester Medical Center, 601 Elmwood Ave., Rochester, NY 14642, USA
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99926
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Kambo A, Sharma VS, Casteel DE, Woods VL, Pilz RB, Boss GR. Nitric oxide inhibits mammalian methylmalonyl-CoA mutase. J Biol Chem 2005; 280:10073-82. [PMID: 15647267 DOI: 10.1074/jbc.m411842200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Methylmalonyl-CoA mutase is a key enzyme in intermediary metabolism, and children deficient in enzyme activity have severe metabolic acidosis. We found that nitric oxide (NO) inhibits methylmalonyl-CoA mutase activity in rodent cell extracts. The inhibition of enzyme activity occurred within minutes and was not prevented by thiols, suggesting that enzyme inhibition was not occurring via NO reaction with cysteine residues to form nitrosothiol groups. Enzyme inhibition was dependent on the presence of substrate, implying that NO was reacting with cobalamin(II) (Cbl(II)) and/or the deoxyadenosyl radical (.CH(2)-Ado), both of which are generated from the co-factor of the enzyme, 5'-deoxyadenosyl-cobalamin (AdoCbl), on substrate binding. Consistent with this hypothesis was the finding that high micromolar concentrations (> or =600 microm) of oxygen also inhibited enzyme activity. To study the mechanism of NO reaction with AdoCbl, we simulated the enzymatic reaction by photolyzing AdoCbl, and found that even at low NO concentrations, NO reacted with both the generated Cbl(II) and .CH(2)-Ado indicating that NO could effectively compete with the back formation of AdoCbl. Thus, NO inhibition of methylmalonyl-CoA mutase appeared to be from the reaction of NO with both AdoCbl intermediates (Cbl(II) and .CH(2)-Ado) generated during the enzymatic reaction. The inhibition of methylmalonyl-CoA mutase by NO was likely of physiological relevance because a NO donor inhibited enzyme activity in intact cells, and scavenging NO from cells or inhibiting cellular NO synthesis increased methylmalonyl-CoA mutase activity when measured subsequently in cell extracts.
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Affiliation(s)
- Amanpreet Kambo
- Department of Medicine, and Cancer Center, University of California, 9500 Gilman Dr., La Jolla, California 92093-0652, USA
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99927
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Lee JK, Stewart-Jones G, Dong T, Harlos K, Di Gleria K, Dorrell L, Douek DC, van der Merwe PA, Jones EY, McMichael AJ. T cell cross-reactivity and conformational changes during TCR engagement. ACTA ACUST UNITED AC 2005; 200:1455-66. [PMID: 15583017 PMCID: PMC2211951 DOI: 10.1084/jem.20041251] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
All thymically selected T cells are inherently cross-reactive, yet many data indicate a fine specificity in antigen recognition, which enables virus escape from immune control by mutation in infections such as the human immunodeficiency virus (HIV). To address this paradox, we analyzed the fine specificity of T cells recognizing a human histocompatibility leukocyte antigen (HLA)-A2–restricted, strongly immunodominant, HIV gag epitope (SLFNTVATL). The majority of 171 variant peptides tested bound HLA-A2, but only one third were recognized. Surprisingly, one recognized variant (SLYNTVATL) showed marked differences in structure when bound to HLA-A2. T cell receptor (TCR) recognition of variants of these two peptides implied that they adopted the same conformation in the TCR–peptide–major histocompatibility complex (MHC) complex. However, the on-rate kinetics of TCR binding were identical, implying that conformational changes at the TCR–peptide–MHC binding interface occur after an initial permissive antigen contact. These findings have implications for the rational design of vaccines targeting viruses with unstable genomes.
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Affiliation(s)
- Jean K Lee
- Human Immunology Unit, Medical Research Council, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford OX3 9DS, England, UK
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99928
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Kopp J, Wang GY, Kulmburg P, Schultze-Mosgau S, Huan JN, Ying K, Seyhan H, Jeschke MD, Kneser U, Bach AD, Ge SD, Dooley S, Horch RE. Accelerated wound healing by in vivo application of keratinocytes overexpressing KGF. Mol Ther 2005; 10:86-96. [PMID: 15233945 DOI: 10.1016/j.ymthe.2004.04.016] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2003] [Accepted: 04/26/2004] [Indexed: 11/18/2022] Open
Abstract
Epidermal regeneration is a complex process, strongly influenced by growth factors, including keratinocyte growth factor (KGF). The objective of this study was to establish immortalized HaCaT keratinocytes and KMST-6-fibroblasts stably expressing KGF. Transfection efficiency, genomic integration, and functionality of the transgene were determined by ELISA and PCR, and KGF-expressing clones were selected using an air-liquid interface test system. HaCaT cells displayed stronger transgene expression compared to transfected fibroblasts, and the most effective HaCaT clone was incubated on a membrane carrier to form a "membrane cell graft." Twenty-one superficial second-degree burn wounds were created in each of three pigs, and wound healing capacity of the generated "polypeptide cell delivery system" after grafting was examined. Untransfected HaCaT keratinocytes and membrane-covered and untreated burn wounds served as controls. Histological and macroscopical follow-up revealed that grafting of transfected HaCaT cells resulted in complete reepithelialization within 5 days, while wounds covered with untransfected cells needed 2 days longer. At untreated sites, a thin epithelium was detectable after 10 days. The results indicate that wound healing processes can be stimulated distinctly by growth factors secreted from HaCaT cells, with a prominent role for transgenic KGF.
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Affiliation(s)
- Jürgen Kopp
- Department of Plastic and Hand Surgery, University Medical Center, Friedrich-Alexander-University, 91054 Erlangen-Nürnberg, Germany.
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99929
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Coutré S, Gotlib J. Targeted treatment of hypereosinophilic syndromes and chronic eosinophilic leukemias with imatinib mesylate. Semin Cancer Biol 2005; 14:307-15. [PMID: 15305431 DOI: 10.1016/j.semcancer.2004.03.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Idiopathic hypereosinophilic syndrome (HES) and chronic eosinophilia leukemia (CEL) represent the most recent additions to the list of molecularly defined chronic myeloproliferative disorders. Beginning with the observation that imatinib mesylate (Gleevec) could elicit rapid and complete hematologic remissions in a proportion of patients with HES, a reverse bedside-to-bench translational research effort led to the discovery of FIP1L1-PDGFRA, a novel fusion gene on chromosome 4q12 whose product is an imatinib-sensitive protein tyrosine kinase. FIP1L1-PDGFRA is the first description of a gain-of-function fusion gene derived from an interstitial chromosomal deletion rather than a reciprocal translocation. Empiric use of imatinib in HES and CEL provides a dramatic example of how the development of targeted therapeutics can provide tremendous insight into the molecular etiology of what appear to be a diverse and otherwise indecipherable collection of diseases. In this review, we discuss the role of imatinib in HES/CEL and other malignancies characterized by constitutively activated tyrosine kinases, and examine molecular features of the FIP1L1-PDGFRA fusion.
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Affiliation(s)
- Steven Coutré
- Division of Hematology, Stanford University School of Medicine, CA 94305-5821, USA.
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99930
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Tovote P, Meyer M, Beck-Sickinger AG, von Hörsten S, Ove Ogren S, Spiess J, Stiedl O. Central NPY receptor-mediated alteration of heart rate dynamics in mice during expression of fear conditioned to an auditory cue. ACTA ACUST UNITED AC 2005; 120:205-14. [PMID: 15177939 DOI: 10.1016/j.regpep.2004.03.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2003] [Revised: 03/05/2004] [Accepted: 03/15/2004] [Indexed: 11/24/2022]
Abstract
Neuropeptide Y (NPY) is involved in the regulation of emotionality including fear and anxiety, which modulate autonomic control of cardiovascular function. We therefore investigated the central effects of porcine NPY, selective Y1, Y2 and Y5 receptor agonists and a Y1 receptor antagonist on heart rate (HR) and HR variability in freely moving mice using auditory fear conditioning. Intracerebroventricular (i.c.v.) injections were applied 15 min before the tone-dependent memory test. NPY dose-dependently induced bradycardia associated with decreased HR variability, and blunted the stress-induced tachycardic response. The selective Y1 receptor antagonist BIBO 3304 blocked the NPY- and Y1-receptor agonist-induced suppression of conditioned tachycardia without affecting basal HR. The tachycardia elicited by both conditioned and unconditioned stressor was effectively attenuated by the Y1 receptor agonist. These results suggest a specific contribution of Y1, but not Y2 and Y5 receptors, to modulation of emotional responses most likely unrelated to impairment or modulation of memory. The NPY-induced bradycardia is attributed to not yet characterized NPY receptor subtypes other than Y1, Y2 and Y5, or a complex receptor interaction. In conclusion, NPY mediates central inhibition of sympathetic outflow, potentially coupled with attenuation of parasympathetic tone, i.e., mechanisms that may be associated with the reported anxiolytic action.
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Affiliation(s)
- Philip Tovote
- Department of Molecular Neuroendocrinology, Max Planck Institute for Experimental Medicine, Göttingen, Germany
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99931
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Tewari PC, Zhang B, Bluestein BI. Analytical and clinical evaluation of the Bayer ADVIA Centaur homocysteine assay. Clin Chim Acta 2005; 342:171-8. [PMID: 15026278 DOI: 10.1016/j.cccn.2003.12.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2003] [Revised: 12/23/2003] [Accepted: 12/23/2003] [Indexed: 11/26/2022]
Abstract
BACKGROUND Cardiovascular disease (CVD) is the leading cause of death in the United States. Elevations in homocysteine (Hcy) have been associated with increased risk of acute coronary syndrome, stroke and peripheral vascular disease. Increased utilization of Hcy as a risk marker has prompted the need for high throughput methods that are simple to use and analytically accurate and precise. METHODS We report the performance characteristics of the automated Bayer ADVIA Centaur chemiluminescent Hcy assay. Centaur Hcy is based on a three-step procedure: (1) reduction of Hcy disulfides to free Hcy, (2) enzymatic conversion of free Hcy to S-adenosyl Hcy (SAH) and (3) quantitation of SAH in a competitive immunoassay (labeled anti-SAH antibody: magnetic particles coupled with SAH). RESULTS Total assay precision ranged from 3.5% to 6.8% at 4.9-62 micromol/Hcy; linearity undiluted from 0 to 65 micromol/l, up to 650 micromol/l with automatic dilution. Method comparisons with fluorescent polarization immunoassay and high-performance liquid chromatography (HPLC) gave linear regression equations with slopes between 0.95 and 1.0. Measurement of Hcy concentrations in apparently healthy populations yielded middle 95th percentile of 9.7 micromol/l, consistent with epidemiologic studies suggesting that 9-10 micromol/l represents the lower threshold of a population at risk of CVD. CONCLUSIONS The Centaur Hcy assay is a sensitive and precise assay for the measurement of Hcy.
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Affiliation(s)
- Prakash C Tewari
- Bayer Healthcare LLC, Diagnostics Division, Laboratory Testing Segment, Research and Development, 511 Benedict Avenue, Tarrytown, NY 10591, USA.
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99932
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Xia D, Li F, Xiang J. Engineered fusion hybrid vaccine of IL-18 gene-modified tumor cells and dendritic cells induces enhanced antitumor immunity. Cancer Biother Radiopharm 2005; 19:322-30. [PMID: 15285878 DOI: 10.1089/1084978041424990] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Dendritic cell (DC)-tumor fusion hybrid vaccines that facilitate antigen presentation represent a novel powerful strategy in cancer immunotherapy. In our study, we investigated the antitumor immunity derived from the vaccination of fusion hybrids between engineered J558/IL-18 myeloma cells secreting Th1 cytokine IL-18 and DCs. DC/J558/IL-18 could secret a higher level of IL-18 than DCs, efficiently expressed J558 tumor antigen P1A, and enhanced ability of allogeneic T cell stimulation when compared to J558/IL-18. Our data showed that the immunization of BALB/c mice with DC/J558/IL-18 hybrids induced the most potent protective immunity against 1 x 10(6) cells with a J558 tumor challenge, compared to those immunized with the mixture of DCs and J558/IL-18, J558/IL-18, or J558. Furthermore, the immunization of mice with engineered DC/J558/IL-18 hybrids elicited stronger NK activity and J558 tumor-specific cytotoxic T lymphocyte (CTL) responses in vitro. In addition, DC/J558/IL-18 tumor cells into syngeneic mice induced a Th1 dominant immune response to J558 and resulted in tumor regression, which indicated that the antitumor effect mediated by DC/J558/IL-18 appeared to be dependent on TH1 cytokine production. These results demonstrate that the engineered fusion hybrid vaccines that combine Th1 gene-modified tumor with DCs may be an attractive strategy for cancer immunotherapy.
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Affiliation(s)
- Dajing Xia
- Research Unit, Saskatchewan Cancer Agency, Departments of Oncology, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, 20 Campus Drive, Saskatoon, Saskatchewan S7N 4H4, Canada
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99933
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Lachal S, Ford J, Shulkes A, Baldwin GS. PPARalpha agonists stimulate progastrin production in human colorectal carcinoma cells. ACTA ACUST UNITED AC 2005; 120:243-51. [PMID: 15177943 DOI: 10.1016/j.regpep.2004.03.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 03/15/2004] [Accepted: 03/26/2004] [Indexed: 02/08/2023]
Abstract
The three subtypes of peroxisome proliferator activated-receptors (PPARalpha, delta and gamma) control the storage and metabolism of fatty acids. Treatment of rats with the PPARalpha ligand ciprofibrate increases serum gastrin concentrations, and several lines of evidence suggest that non-amidated gastrins act as growth factors for the colonic mucosa. The aim of the present study was to investigate the expression of PPARs and the effect of PPAR ligands on gastrin production and cell proliferation in human colorectal carcinoma (CRC) cell lines. mRNAs for all three PPAR subtypes were detected by PCR in all CRC cell lines tested. The concentrations of progastrin, but not of glycine-extended or amidated gastrin, measured by radioimmunoassay in LIM 1899 conditioned media and cell extracts were significantly increased by treatment with the PPARalpha ligand clofibrate. Similar increases in progastrin were seen following treatment with the PPARalpha ligands ciprofibrate and fenofibrate, but not with bezafibrate, gemfibrozil or Wy 14643. The PPARgamma agonist rosiglitazone had no significant effect on progastrin production. The PPARalpha ligand clofibrate also stimulated proliferation of the LIM 1899 cell line. We conclude that some PPARalpha ligands increase progastrin production by the human CRC cell line LIM 1899, and that clofibrate increases proliferation of LIM 1899 cells. These studies have revealed a relationship between PPARs and gastrin, two regulatory molecules implicated in the pathogenesis of CRC.
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Affiliation(s)
- Shamilah Lachal
- Department of Surgery ARMC, University of Melbourne, Department of Surgery, Austin Health, Heidelberg, Victoria 3084, Australia
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99934
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Benedetti P, Mannhold R, Cruciani G, Ottaviani G. GRIND/ALMOND investigations on CysLT1 receptor antagonists of the quinolinyl(bridged)aryl type. Bioorg Med Chem 2005; 12:3607-17. [PMID: 15186845 DOI: 10.1016/j.bmc.2004.04.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2004] [Accepted: 04/16/2004] [Indexed: 11/29/2022]
Abstract
One of the current routes in developing antiasthmatics is CysLT(1) receptor antagonism. For a training set of 54 CysLT(1) receptor antagonists of the quinolinyl(bridged)aryl type we developed chemometric QSAR models applying GRID independent descriptors (=GRIND). PLS analysis resulted in a two-component model explaining 67% of the variance for CysLT(1) receptor binding (r2=0.67, SDEC = 0.47, q2=0.54). GRIND variables 11-50 and 22-55 are responsible for high-affinity binding; variable 11-62 is detrimental. The predictivity of the above chemometric model is tested with a set of 69 CysLT(1) receptor antagonists, exhibiting varying chemical similarity to the training set. Nearly 50% of the test set are quite well predicted. The quality of prediction coincides in part with chemical subclassification: phenylene bridged compounds are quite well predicted; for structures with bridging heterocycles predictions are rather poor. For explaining the outlier behavior, a PLS discriminant analysis including the training set and the strongest outliers of the test set was performed. The scores plot of discriminant PLS shows an almost complete separation between the two subsets. A PLS coefficients plot explains which GRIND variables are important for the discrimination between the training set and the outliers of the test set.
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Affiliation(s)
- Paolo Benedetti
- Dipartimento di Chimica, Laboratorio di Chemiometria, Università di Perugia, Via Elce di Sotto, 10, I-06123 Perugia, Italy
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99935
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Santra S, Gilkerson RW, Davidson M, Schon EA. Ketogenic treatment reduces deleted mitochondrial DNAs in cultured human cells. Ann Neurol 2005; 56:662-9. [PMID: 15389892 DOI: 10.1002/ana.20240] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Impairment of mitochondrial energy metabolism has been associated with a wide range of human disorders. Large-scale partial deletions of mitochondrial DNA (mtDNA) cause sporadic Kearns-Sayre syndrome, a fatal multisystem disorder, in which the majority of mtDNAs in affected tissues have deletions (Delta-mtDNAs). Since most mtDNA-related diseases, including Kearns-Sayre syndrome, are recessive, only a few wild-type mtDNAs can compensate for the deleterious effects of many Delta-mtDNAs. We have developed a pharmacological approach to reduce the proportion of Delta-mtDNAs in vitro, in which we grow cells in medium containing ketone bodies, replacing glucose as the carbon source. Cells containing 100% Delta-mtDNA died after 5 days of treatment, whereas those containing 100% wild-type mtDNA survived. Furthermore, in a cloned heteroplasmic cell line, the proportion of wild-type mtDNA increased from 13% initially to approximately 22% after 5 days in ketogenic medium and was accompanied by a dramatic improvement in mitochondrial protein synthesis. We also present evidence that treatment with ketone bodies caused "heteroplasmic shifting" not only among cells (ie, intercellular selection) but also within cells (ie, intracellular selection). The demonstration that ketone bodies can distinguish between normal and respiratorily compromised cells points to the potential use of a ketogenic diet to treat patients with heteroplasmic mtDNA disorders.
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Affiliation(s)
- Sumana Santra
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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99936
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Mishra R, Simonson MS. Saturated free fatty acids and apoptosis in microvascular mesangial cells: palmitate activates pro-apoptotic signaling involving caspase 9 and mitochondrial release of endonuclease G. Cardiovasc Diabetol 2005; 4:2. [PMID: 15642122 PMCID: PMC546189 DOI: 10.1186/1475-2840-4-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 01/10/2005] [Indexed: 01/22/2023] Open
Abstract
Background In type 2 diabetes, free fatty acids (FFA) accumulate in microvascular cells, but the phenotypic consequences of FFA accumulation in the microvasculature are incompletely understood. Here we investigated whether saturated FFA induce apoptosis in human microvascular mesangial cells and analyzed the signaling pathways involved. Methods Saturated and unsaturated FFA-albumin complexes were added to cultured human mesangial cells, after which the number of apoptotic cells were quantified and the signal transduction pathways involved were delineated. Results The saturated FFA palmitate and stearate were apoptotic unlike equivalent concentrations of the unsaturated FFA oleate and linoleate. Palmitate-induced apoptosis was potentiated by etomoxir, an inhibitor of mitochondrial β-oxidation, but was prevented by an activator of AMP-kinase, which increases fatty acid β-oxidation. Palmitate stimulated an intrinsic pathway of pro-apoptotic signaling as evidenced by increased mitochondrial release of cytochrome-c and activation of caspase 9. A caspase 9-selective inhibitor blocked caspase 3 activation but incompletely blocked apoptosis in response to palmitate, suggesting an additional caspase 9-independent pathway. Palmitate stimulated mitochondrial release of endonuclease G by a caspase 9-independent mechanism, thereby implicating endonuclease G in caspase 9-indpendent regulation of apoptosis by saturated FFA. We also observed that the unsaturated FFA oleate and linoleate prevented palmitate-induced mitochondrial release of both cytochrome-c and endonuclease G, which resulted in complete protection from palmitate-induced apoptosis. Conclusions Taken together, these results demonstrate that palmitate stimulates apoptosis by evoking an intrinsic pathway of proapoptotic signaling and identify mitochondrial release of endonuclease G as a key step in proapoptotic signaling by saturated FFA and in the anti-apoptotic actions of unsaturated FFA.
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Affiliation(s)
- Rangnath Mishra
- Division of Nephrology, Department of Medicine, School of Medicine, Case Western Reserve University and University Hospitals of Cleveland, Cleveland, Ohio 44106, USA
| | - Michael S Simonson
- Division of Nephrology, Department of Medicine, School of Medicine, Case Western Reserve University and University Hospitals of Cleveland, Cleveland, Ohio 44106, USA
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99937
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Vance JE, Vance DE. Metabolic insights into phospholipid function using gene-targeted mice. J Biol Chem 2005; 280:10877-80. [PMID: 15642727 DOI: 10.1074/jbc.r400038200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
- Jean E Vance
- Canadian Institutes of Health Research Group on Molecular and Cell Biology of Lipids, Department of Medicine, University of Alberta, Edmonton, Alberta T6G 2S2, Canada.
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99938
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Sadek JR, Johnson SA, White DA, Salmon DP, Taylor KI, Delapena JH, Paulsen JS, Heaton RK, Grant I. Retrograde amnesia in dementia: comparison of HIV-associated dementia, Alzheimer's disease, and Huntington's disease. Neuropsychology 2005; 18:692-9. [PMID: 15506837 DOI: 10.1037/0894-4105.18.4.692] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Remote memory was assessed in persons with HIV-associated dementia (HIV-D), probable Alzheimer's disease (AD), and Huntington's disease (HD) and in healthy controls. The clinical groups were similar in overall dementia severity. Each clinical group exhibited impairments on remote memory tests relative to controls; however, temporally graded memory loss with selective preservation of older information was observed in the AD group but not the HD or HIV-D group. Analysis of cued retrieval indicated a preferential cuing benefit for the HIV-D and HD groups relative to the AD group. The similar pattern of remote memory performance demonstrated by the HIV-D and HD groups is a novel finding and suggests a subcortically mediated retrograde amnesia in HIV-D. The temporally graded pattern and the abnormal cued retrieval performance in the AD group are consistent with a consolidation deficit associated with extrahippocampal (cortical) and hippocampal damage.
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Affiliation(s)
- Joseph R Sadek
- Department of Psychiatry, University of California, San Diego, CA 92103, USA.
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99939
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Bunin N, Aplenc R, Iannone R, Leahey A, Grupp S, Monos D, Pierson G. Unrelated donor bone marrow transplantation for children with severe aplastic anemia: minimal GVHD and durable engraftment with partial T cell depletion. Bone Marrow Transplant 2005; 35:369-73. [PMID: 15640818 DOI: 10.1038/sj.bmt.1704803] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Both increased graft rejection and increased graft vs host disease (GVHD) remain obstacles to success for unrelated donor (URD) BMT for patients with SAA. Partial T cell depletion (PTCD) may decrease the risk of severe GVHD, while still maintaining sufficient donor T lymphocytes to ensure engraftment. We report on 12 patients with SAA who underwent PTCD URD BMT. All patients had failed medical therapy or relapsed following initial responses, and were transfusion dependent. The median age was 6 years, and there were five males. Donors were matched for four patients, and mismatched for eight. All patients received total body irradiation with either Ara-C or thiotepa and cyclophosphamide. PTCD was accomplished using monoclonal antibody T10B9 or OKT3 and complement. All patients engrafted, with a median time of 18 days to ANC >500. Only one patient had greater than grade II acute GVHD; two patients had limited and one patient extensive chronic GVHD. Nine patients are alive and transfusion independent at a median months post BMT. Three patients died from infection or renal failure. This series suggests that an aggressive immunosuppressive conditioning regimen with PTCD results in successful engraftment and minimal GVHD in pediatric patients with SAA, even with HLA mismatched donors.
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Affiliation(s)
- N Bunin
- The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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99940
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Lerman C, Patterson F, Berrettini W. Treating Tobacco Dependence: State of the Science and New Directions. J Clin Oncol 2005; 23:311-23. [PMID: 15637394 DOI: 10.1200/jco.2005.04.058] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite almost two decades of intensive tobacco control efforts, nearly one quarter of Americans continue to smoke. The two United States Food and Drug Administration–approved medications used to treat tobacco dependence, bupropion and nicotine replacement therapy, are effective for only a fraction of smokers. Investigations of medications approved for affective disorders and other forms of substance abuse, such as fluoxetine and naltrexone, have yielded mixed results as tobacco dependence treatments. A particular challenge in tobacco dependence treatment is the development of effective approaches for smokers with unique needs, such as cancer patients and pregnant women. Despite new developments in these areas, significant gaps in knowledge and practice remain. Basic research in the neurobiologic and genetic basis of nicotine dependence offers promise for the development of novel and more effective treatment approaches. For example, emerging research in pharmacogenetics explores how genetic variation in drug-metabolizing enzymes and drug targets modifies response to pharmacotherapy. These discoveries could someday help practitioners to individualize the type, dosage, and duration of tobacco dependence treatment based on genotype, and maximize the efficacy.
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Affiliation(s)
- Caryn Lerman
- Tobacco Use Research Center, 3535 Market St, Suite 4100, Philadelphia, PA 19104, USA.
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99941
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Abstract
Every year, more than 945000 people develop colorectal cancer worldwide, and around 492000 patients die. This form of cancer develops sporadically, in the setting of hereditary cancer syndromes, or on the basis of inflammatory bowel diseases. Screening and prevention programmes are available for all these causes and should be more widely publicised. The adenoma-carcinoma sequence is the basis for development of colorectal cancer, and the underlying molecular changes have largely been identified. Prognosis depends on factors related to the patient, treatment, and tumour, and the expertise of the treatment team is one of the major determinants of outcome. New information on the molecular basis of this cancer have led to the development of targeted therapeutic options, which are being tested in clinical trials. Further clinical progress will largely depend on the broader implementation of multidisciplinary treatment strategies following the principles of evidence-based medicine.
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Affiliation(s)
- Jürgen Weitz
- Department of Surgery, University of Heidelberg, Heidelberg, Germany
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99942
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Brown TT, Zelnik DL, Dobs AS, Evans DB, Chiao PJ. Fish oil supplementation in the treatment of cachexia in pancreatic cancer patients. INTERNATIONAL JOURNAL OF GASTROINTESTINAL CANCER 2005. [PMID: 15361649 DOI: 10.1385/ijgc:] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Patients with pancreatic cancer often experience a loss of weight and appetite, known as the anorexia-cachexia syndrome, which is associated with decreased quality of life and reduced survival. Research into the biological mechanisms of cachexia has demonstrated that an array of inflammatory mediators and tumor-derived factors cause appetite suppression, skeletal muscle proteolysis, and lipolysis,producing an overall hypercatabolic state that contributes to loss of fat and lean body mass. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been shown to modulate levels of proinflammatory cytokines, hepatic acute phase proteins, eicosanoids, and tumor-derived factors in animal models of cancer and may reverse some aspects of the process of cachexia. Results of clinical trials of n-3 PUFAs in the form of fish oils have been mixed, but should encourage further investigation into dietary fish oil supplementation, including the most effective route of administration and the proper dosage to promote optimal weight maintenance and to limit side effects. Concerns about standardization and quality control should also be considered. With the current available evidence, a recommendation for the use of omega 3 polyunsaturated fatty acids in pancreatic cancer cachexia is premature.
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Affiliation(s)
- Todd T Brown
- Johns Hopkins University School of Medicine, Division of Endocrinology and Metabolism, Center for Complementary and Alternative Medicine, Baltimore, MD 21287, USA
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99943
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España L, Fernández Y, Rubio N, Torregrosa A, Blanco J, Sierra A. Overexpression of Bcl-xL in human breast cancer cells enhances organ-selective lymph node metastasis. Breast Cancer Res Treat 2005; 87:33-44. [PMID: 15377849 DOI: 10.1023/b:brea.0000041579.51902.89] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Lymph node metastasis are the first prognostic factor in breast cancer diagnosis and an early event in metastatic spread. To assess the role of anti-apoptotic proteins in lymph node metastatic progression of human breast cancer cells we analyzed the metastatic activity of MDA-MB-435 cells transfected with the Bcl-xL gene, after orthotopic inoculation in Nude Balb/c and in SCID mice. The luciferase gene was introduced by permanent transfection in the 435/Bcl-xL and 435/Neo cells and used as a tumor marker to measure the number of tumor cells lodged in lymph nodes. We found that 435/Bcl-xL tumor cells had enhanced organ-specific metastatic activity, preferentially lodging in peripheral lymph nodes, where at 45 days post-implantation we found 7 x 10(6) +/- 6 x 10(6) 435/Bcl-xL.luc and 2 +/- 1.1 435/Neo.luc luciferase tagged tumor cell equivalents (TCEs). Metastases were abrogated in mice in which orthotopic tumors were induced with 435/Bcl-xL-antisense cells. Additionally, in vitro experiments show that in 435 cells Bcl-xL-antisense can override the emergence of resistance to apoptosis induced by TNF- alpha and TGF- beta in cells overexpressing Bcl-xL, increasing also adhesion to extracellular matrix proteins. These results point to the relevance of Bcl-xL overexpression inducing lymph node metastasis of breast cancer cells, and to the value of this gene as a target for therapy in order to prevent metastasis.
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Affiliation(s)
- Laura España
- Centre d'Oncologia Molecular, Institut de Recerca Oncológica, Hospital Duran i Reynals, Ciutat Sanitaria i Universitaria de Bellvitge, Barcelona, Spain
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99944
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Abstract
Plasma high-density lipoprotein cholesterol (HDL-C) concentrations are genetically determined to a great extent, and quantitative trait locus (QTL) analysis has been used to identify chromosomal regions containing genes regulating HDL-C levels. We discuss new genes found to participate in HDL metabolism. We also summarize 37 mouse and 30 human QTLs for plasma HDL-C levels, finding that all but three of the mouse QTLs have been confirmed by a second cross or a homologous human QTL, that the mouse QTL map is almost saturated because 92% of recently reported QTLs are repeats of those already found, and that 28 of the 30 human QTLs are located in regions homologous to mouse QTLs. This high degree of concordance between mouse and human QTLs suggests that the underlying genes may be the same. Strategies to more rapidly identify genes underlying mouse and human QTLs for HDL-C include focusing on the mouse and using mouse–human homologies, combining crosses, and haplotyping to narrow the region. Sequence analysis and expression studies can distinguish candidate genes consistent across multiple mouse crosses, and testing the candidate genes in human association studies can provide additional evidence for the candidacy of a gene. Together these strategies can accelerate the pace of finding genes that regulate HDL.
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Affiliation(s)
- Xiaosong Wang
- Jackson Laboratory, 600 Main St, Bar Harbor, ME 04609, USA.
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99945
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Urbano-Márquez A, Fernández-Solà J. Effects of alcohol on skeletal and cardiac muscle. Muscle Nerve 2005; 30:689-707. [PMID: 15490485 DOI: 10.1002/mus.20168] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The acute and chronic toxic effects of alcohol on skeletal and cardiac muscle are clinically important. Muscle weakness and atrophy are the main manifestations of skeletal myopathy, and arrhythmias and progressive left-ventricular dysfunction are those of cardiomyopathy. Most patients remain asymptomatic from these effects for a long time. Myocyte atrophy and death are the main pathological findings. A clear dose-related effect has been established with ethanol consumption, with gender and some specific gene polymorphisms being factors of increased susceptibility to alcohol-induced muscle damage. Pathogenic mechanisms are pleiotropic, the most relevant being disturbances in carbohydrate, protein, and energy cell turnover, signal transduction, and induction of apoptosis and gene dysregulation. Ethanol abstinence is the only effective treatment, although controlled drinking is useful in patients who do not achieve abstinence. Persistent high-dose consumption results in deterioration of muscle and heart function, with a high mortality due to arrhythmias and progression of heart failure.
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Affiliation(s)
- Alvaro Urbano-Márquez
- Alcohol Research Unit, Internal Medicine Department, Hospital Clinic, Institut d'Investigacions Biomèdiques August Pi i Suyner, University of Barcelona, Barcelona 08036, Spain.
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99946
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Jadhav S, Petrie J, Ferrell W, Cobbe S, Sattar N. Insulin resistance as a contributor to myocardial ischaemia independent of obstructive coronary atheroma: a role for insulin sensitisation? Heart 2005; 90:1379-83. [PMID: 15547007 PMCID: PMC1768561 DOI: 10.1136/hrt.2004.035170] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
There is good evidence to suggest that insulin resistance and its surrogate markers are at least modest independent cardiovascular risk factors. However, as well as long term effects on atheromatous coronary disease, there is a well described correlation between markers of insulin resistance and endothelial dysfunction. In this review, the evidence for a relation between endothelial dysfunction and myocardial ischaemia is summarised. The evidence for a correlation between insulin resistance and endothelial dysfunction and the proposed cellular mechanisms are also examined. Finally, the potential role for insulin sensitising strategies is looked at and recent data examining their effects on both endothelial function and clinical symptoms is examined. In conclusion, it was found that insulin sensitising modalities have a potential role in the amelioration of angina and that randomised controlled studies are therefore warranted.
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Affiliation(s)
- S Jadhav
- Department of Medical Cardiology, Glasgow Royal Infirmary, Glasgow G31 2ER, UK.
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99947
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Affiliation(s)
- Itzhak Brook
- Department of Pediatrics, Georgetown University School of Medicine, Washington, DC 20016, USA.
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99948
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Cziraky MJ. Management of dyslipidemia in patients with metabolic syndrome. J Am Pharm Assoc (2003) 2005; 44:478-88; quiz 489-90. [PMID: 15372869 DOI: 10.1331/1544345041475643] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To review the management of dyslipidemia in patients with metabolic syndrome. DATA SOURCES Medline search (2000-2002) conducted for English language articles using the search terms metabolic syndrome, impaired fasting glucose, glucose intolerance, and antilipemic agents; selective search for clinical trials of lipid therapy conducted in dialogue databases (1990-2002). In addition, current dyslipidemia treatment guidelines reviewed. STUDY SELECTION By the author. DATA EXTRACTION By the author. DATA SYNTHESIS The metabolic syndrome is increasingly recognized as a strong predictor of patient risk for developing coronary artery disease (CAD). It is associated with an atherogenic dyslipidemia characterized by elevated levels of triglycerides, reduced levels of high-density lipoprotein cholesterol (HDL-C) and a preponderance of small dense low-density lipoprotein (LDL) particles. Controlled clinical trials show similar or greater cardiovascular benefits from lipid-modifying therapies in patient subgroups with diabetes, impaired fasting glucose, and metabolic syndrome, compared with overall study populations. Current guidelines recommend intensified lipid management. Therapeutic lifestyle changes, with emphasis on weight loss, are particularly important for patients with metabolic syndrome. Statins are first-line therapy for all patients whose LDL-C levels are above goal. Combination therapy may often be necessary to control all lipid abnormalities adequately. Both niacin and fibrates provide additional benefits, particularly on triglyceride and HDL-C levels. Recent clinical studies show that these agents, in combination with statins, are safe and effective for the treatment of atherogenic dyslipidemia. CONCLUSION Atherogenic dyslipidemia represents an important modifiable CAD risk factor. Combination therapy with agents that focus on all of the components of the mixed dyslipidemia that often occurs in persons with diabetes and the metabolic syndrome may be expected to reduce cardiovascular morbidity and mortality.
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Affiliation(s)
- Mark J Cziraky
- HealthCore Inc., 800 Delaware Avenue, Fifth Floor, Wilmington, Delaware 19801-1366 USA.
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99949
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Schulingkamp RJ, Aloyo V, Tallarida RJ, Raffa RB. Changes in aorta alpha1-adrenoceptor number and affinity during one year of streptozotocin-induced diabetes in rats. Pharmacology 2005; 74:23-30. [PMID: 15640611 DOI: 10.1159/000083211] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2004] [Accepted: 10/11/2004] [Indexed: 11/19/2022]
Abstract
alpha(1)-Adrenoceptor function and density in isolated thoracic aorta were measured during the course of streptozotocin-induced diabetes in rats. Diabetes was induced by a single tail vein injection of streptozotocin (60 mg/kg) and was verified by four measures (blood glucose level, increase in food intake, increase in water intake, and characteristic weight changes). Diabetes produced a significant increase in isolated aorta sensitivity to alpha(1)-adrenoceptor activation, manifested as a significant (p < 0.05) decrease in the A(50) value for phenylephrine and an increase in the A(50) (control)/A(50) (diabetic) ratio (1.2, 1.7, and 2.0, respectively) with increasing length of diabetes (4, 12 and 52 weeks). There was a large and biphasic change in receptor density (B(max)), without a significant change (p > 0.05) in either agonist (phenylephrine) or antagonist (prazosin) affinities (K(A) and pA(2) values, respectively). These results suggest compensatory mechanisms in receptor number and abnormalities in 2nd messenger transduction and can help direct efforts for improving antihypertensive or other pharmacological therapy for diabetic patients.
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MESH Headings
- Adrenergic alpha-1 Receptor Agonists
- Adrenergic alpha-1 Receptor Antagonists
- Animals
- Aorta, Thoracic/physiopathology
- Binding Sites
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/physiopathology
- Dose-Response Relationship, Drug
- In Vitro Techniques
- Isometric Contraction/drug effects
- Male
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiopathology
- Phenylephrine/pharmacology
- Prazosin/pharmacology
- Radioligand Assay
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, alpha-1/biosynthesis
- Streptozocin
- Time Factors
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Affiliation(s)
- Robert J Schulingkamp
- Department of Pharmaceutical Sciences, School of Pharmacy, Temple University, Philadelphia, PA, USA
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99950
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Awad N, Gagnon M, Messier C. The relationship between impaired glucose tolerance, type 2 diabetes, and cognitive function. J Clin Exp Neuropsychol 2005; 26:1044-80. [PMID: 15590460 DOI: 10.1080/13803390490514875] [Citation(s) in RCA: 304] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The present review integrates findings of published studies that have evaluated the cognitive function of treated and untreated type 2 diabetic patients and provides a detailed overview of the neuropsychological assessments conducted. Cognitive deficits are observed in older people with glucose intolerance or untreated diabetes but these deficits appear to be attenuated by treatments that improve glycemic control. Cognitive decrements in treated type 2 diabetic patients are most consistently observed on measures of verbal memory (35% of the measures) and processing speed (45% of the measures) while preserved function is observed on measures of visuospatial, attention, semantic and language function. Some studies suggest that deficits in cognitive functions are associated with poorer glycemic control. A number of other factors, such as depression, cardiovascular and cerebrovascular disease, increase these deficits. We conclude that, in diabetic patients who achieve and maintain good glycemic control, type 2 diabetes only has a small impact on cognitive functions before the age of 70 years. However, early onset of type 2 diabetes, poor glycemic control and the presence of micro- and macrovascular disease may interact to produce early cognitive deficits. In older adults (70 years and over), diabetes likely interacts with other dementing processes such as vascular disease and Alzheimer's disease to hasten cognitive decline.
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Affiliation(s)
- Nesrine Awad
- School of Psychology, University of Ottawa, Ottawa, Ontario, Canada
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