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951.
Protein tyrosine phosphatase PRL-3 in malignant cells and endothelial cells: expression and function 总被引:7,自引:0,他引:7
Rouleau C Roy A St Martin T Dufault MR Boutin P Liu D Zhang M Puorro-Radzwill K Rulli L Reczek D Bagley R Byrne A Weber W Roberts B Klinger K Brondyk W Nacht M Madden S Burrier R Shankara S Teicher BA 《Molecular cancer therapeutics》2006,5(2):219-229
Protein tyrosine phosphatase PRL-3 mRNA was found highly expressed in colon cancer endothelium and metastases. We sought to associate a function with PRL-3 expression in both endothelial cells and malignant cells using in vitro models. PRL-3 mRNA levels were determined in several normal human endothelial cells exposed or unexposed to the phorbol ester phorbol 12-myristate 13-acetate (PMA) and in 27 human tumor cell lines. In endothelial cells, PRL-3 mRNA expression was increased in human umbilical vascular endothelial cells and human microvascular endothelial cells (HMVEC) exposed to PMA. An oligonucleotide microarray analysis revealed that PRL-3 was among the 10 genes with the largest increase in expression on PMA stimulation. Phenotypically, PMA-treated HMVEC showed increased invasion, tube formation, and growth factor-stimulated proliferation. A flow cytometric analysis of cell surface markers showed that PMA-treated HMVEC retained endothelial characteristics. Infection of HMVEC with an adenovirus expressing PRL-3 resulted in increased tube formation. In tumor cells, PRL-3 mRNA levels varied markedly with high expression in SKNAS neuroblastoma, MCF-7 and BT474 breast carcinoma, Hep3B hepatocellular carcinoma, and HCT116 colon carcinoma. Western blotting analysis of a subset of cell line lysates showed a positive correlation between PRL-3 mRNA and protein levels. PRL-3 was stably transfected into DLD-1 colon cancer cells. PRL-3-overexpressing DLD-1 subclones were assessed for doubling time and invasion. Although doubling time was similar among parental, empty vector, and PRL-3 subclones, invasion was increased in PRL-3-expressing subclones. In models of endogenous expression, we observed that the MCF-7 cell line, which expresses high levels of PRL-3, was more invasive than the SKBR3 cell line, which expresses low levels of PRL-3. However, the MDA-MB-231 cell line was highly invasive with low levels of PRL-3, suggesting that in some models invasion is PRL-3 independent. Transfection of a PRL-3 small interfering RNA into MCF-7 cells inhibited PRL-3 expression and cell invasion. These results indicate that PRL-3 is functional in both endothelial cells and malignant cells and further validate PRL-3 as a potentially important molecular target for anticancer therapy. 相似文献
952.
Adverse pregnancy outcomes may be more frequent among sibs of individuals with neural tube defects (NTDs), and transmission of risk in families with an NTD may be more frequent among maternal relatives. In a study designed to evaluate matrilineal risk for NTDs, we compared adverse pregnancy outcomes among maternal and paternal first cousin pregnancies. Pregnancy histories were obtained by interview with 288 uncles and aunts (parents of the first cousin pregnancies) in 48 Irish NTD families. We analyzed pregnancy outcomes (preterm deliveries, stillbirths, and miscarriages) among 1,033 singleton first cousin pregnancies and compared risk among maternal versus paternal relatives. Maternal first cousin pregnancies were more likely to end adversely when compared to paternal first cousin pregnancies (17.4% vs. 11.7%, P = 0.01). In a logistic regression analysis of pregnancies unaffected by birth defects, maternal line remained independently associated with adverse outcomes (odds ratio (OR) = 1.55, 95% confidence interval (CI) 1.06, 2.27) after controlling for NTD type, maternal age, maternal smoking during pregnancy, first cousin pregnancy's year of birth. The excess risk with maternal line related mainly to spina bifida occulta families (OR = 42.4; CI 2.64, 681; P = 0.008); risk in open spina bifida families was 1.24 (CI 0.82, 1.87; P = 0.3). These results support the hypothesis of excess risk for adverse pregnancy outcomes among maternal relatives in NTD families. Further work is needed, epidemiological as well as clinical and molecular, not only to confirm these findings, but also to define the underlying biological mechanisms linking adverse reproductive outcomes, excess maternal risk and occurrence of NTDs. 相似文献
953.
Ghosh A Allamarvdasht M Pan CJ Sun MS Mansfield BC Byrne BJ Chou JY 《Gene therapy》2006,13(4):321-329
Glycogen storage disease type Ia (GSD-Ia) is caused by a deficiency in glucose-6-phosphatase-alpha (G6Pase-alpha), a nine-transmembrane domain, endoplasmic reticulum-associated protein expressed primarily in the liver and kidney. Previously, we showed that infusion of an adeno-associated virus (AAV) serotype 2 vector carrying murine G6Pase-alpha (AAV2-G6Pase-alpha) into neonatal GSD-Ia mice failed to sustain their life beyond weaning. We now show that neonatal infusion of GSD-Ia mice with an AAV serotype 1-G6Pase-alpha (AAV1-G6Pase-alpha) or AAV serotype 8-G6Pase-alpha (AAV8-G6Pase-alpha) results in hepatic expression of the G6Pase-alpha transgene and markedly improves the survival of the mice. However, only AAV1-G6Pase-alpha can achieve significant renal transgene expression. A more effective strategy, in which a neonatal AAV1-G6Pase-alpha infusion is followed by a second infusion at age one week, provides sustained expression of a complete, functional, G6Pase-alpha system in both the liver and kidney and corrects the metabolic abnormalities in GSD-Ia mice for the 57 week length of the study. This effective use of gene therapy to correct metabolic imbalances and disease progression in GSD-Ia mice holds promise for the future of gene therapy in humans. 相似文献
954.
Jimmy N.S.N. Tran Aleta Pupovac Rosanne M. Taylor James S. Wiley Scott N. Byrne Ronald Sluyter 《Experimental dermatology》2010,19(8):e151-e157
Please cite this paper as: Murine epidermal Langerhans cells and keratinocytes express functional P2X7 receptors. Experimental Dermatology 2010; 19 : e151–e157. Abstract: Extracellular ATP via the activation of purinergic P2 receptors has an emerging role in cutaneous biology; however, the distribution of these receptors in mouse skin is poorly defined. This study investigated whether murine epidermal cell subpopulations express functional purinergic P2X7 receptors. P2X7 expression was examined by immunoblotting and immunofluorescence staining of epidermal cells from C57Bl/6 mice. P2X7 function was evaluated by nucleotide‐induced ethidium+ uptake measurements in epidermal cells from C57Bl/6 mice, and from P2X7 deficient mice and wild‐type littermate controls. P2X7 was detected in whole epidermal cell preparations, and specifically on Langerhans cells (LCs) and keratinocytes (KCs). ATP induced ethidium+ uptake into LCs and KCs, with EC50 values of 503 and 482 μm, respectively. BzATP, and to a lesser extent ATPγS and ADP, also induced ethidium+ uptake; while UTP, αβ‐meth‐ATP and NAD were ineffective. ATP‐induced ethidium+ uptake was impaired by Na+ and Mg2+, and the P2X7 antagonist, A‐438079 and was absent in LCs and KCs from P2X7 deficient mice. These results demonstrate that murine LCs and KCs express functional P2X7, and support a role for this receptor in cutaneous biology. 相似文献
955.
Eaton WW Byrne M Ewald H Mors O Chen CY Agerbo E Mortensen PB 《The American journal of psychiatry》2006,163(3):521-528
OBJECTIVE: Individuals with schizophrenia and their relatives tend to have either higher or lower than expected prevalences of autoimmune disorders, especially rheumatoid arthritis, celiac disease, autoimmune thyroid diseases, and type 1 diabetes. The purpose of the study was to estimate the association of schizophrenia with these disorders as well as a range of other autoimmune diseases in a single large epidemiologic study. METHOD: The Danish Psychiatric Register, the National Patient Register, and a register with socioeconomic information were linked to form a data file that included all 7,704 persons in Denmark diagnosed with schizophrenia from 1981 to 1998 and their parents along with a sample of matched comparison subjects and their parents. The data linkage required that the autoimmune disease occur before the diagnosis of schizophrenia. RESULTS: A history of any autoimmune disease was associated with a 45% increase in risk for schizophrenia. Nine autoimmune disorders had higher prevalence rates among patients with schizophrenia than among comparison subjects (crude incidence rate ratios ranging from 1.9 to 12.5), and 12 autoimmune diseases had higher prevalence rates among parents of schizophrenia patients than among parents of comparison subjects (adjusted incidence rate ratios ranging from 1.3 to 3.8). Thyrotoxicosis, celiac disease, acquired hemolytic anemia, interstitial cystitis, and Sj?gren's syndrome had higher prevalence rates among patients with schizophrenia than among comparison subjects and also among family members of schizophrenia patients than among family members of comparison subjects. CONCLUSIONS: Schizophrenia is associated with a larger range of autoimmune diseases than heretofore suspected. Future research on comorbidity has the potential to advance understanding of pathogenesis of both psychiatric and autoimmune disorders. 相似文献
956.
957.
K.-C. Sung S.H. Wild C.D. Byrne 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2013,23(12):1239-1246
Background and aimsWhether lipoprotein (a) [Lp(a)] concentration is associated with metabolic syndrome (MetS) and pre-clinical atherosclerosis in different ethnic groups is uncertain. The association between Lp(a), MetS and a measure of pre-clinical atherosclerosis was studied in a large Asian cohort.Methods and resultsData were analyzed from a South Korean occupational cohort who underwent a cardiac computed tomography (CT) estimation of CAC score and measurements of cardiovascular risk factors (n = 14,583 people). The key exposure was an Lp(a) concentration in the top quartile (>38.64 mg/dL)) with a CAC score >0 as the outcome variable and measure of pre-clinical atherosclerosis. Logistic regression was used to describe the associations. 1462 participants had a CAC score >0. In the lowest Lp(a) quartile (<11.29 mg/dL), 25.8% had MetS, compared with 16.1% in the highest Lp(a) quartile (>38.64 mg/dL (p < 0.001). MetS, and component features, were inversely related to Lp(a) concentration (all p < 0.0001). In the highest Lp(a) quartile group, there was an association between Lp(a) and CAC score >0 in men (OR 1.21[1.05, 1.40], p = 0.008), and women (OR 1.62[1.03, 2.55], p = 0.038), after adjustment for age, sex, lipid lowering therapy, and multiple cardiovascular risk factors. There was no evidence of an interaction between highest quartile Lp(a) and either high LDLc (>147 mg/dL) (p = 0.99), or MetS (p = 0.84) on the association with CAC score >0.ConclusionLp(a) levels are inversely related to MetS and its components. There was a robust association between Lp(a) concentration >38.6 mg/dL and marker of early atherosclerosis in both men and women, regardless of LDLc, level MetS or other cardiovascular risk factors. 相似文献
958.
Browne G Steiner M Roberts J Gafni A Byrne C Dunn E Bell B Mills M Chalklin L Wallik D Kraemer J 《Journal of affective disorders》2002,68(2-3):317-330
BACKGROUND: There is little information on the long-term effects and costs of a combination of Sertraline and interpersonal psychotherapy (IPT) for the treatment of dysthymia in primary care. METHODS: In a single-blind, randomized clinical trial, 707 adults (18-74 years of age inclusive) with DSM-IV dysthymic disorder, with or without past and/or current major depression, as an acute or chronic episode, in a community-based primary care practice in Ontario, Canada, were randomized to treatment with either Sertraline alone (50-200 mg), or IPT alone (10 sessions), or Sertraline plus IPT combined. In the acute treatment phase (first 6 months) all groups received full active treatment. This was followed by an additional 18-month naturalistic follow-up phase. Subjects were assessed for effectiveness of treatment in reducing depressive symptoms using the Montgomery Asberg Depression Rating Scale (MADRS) at 6 months and twice again during the 18-month follow-up by blind independent observers. Treatment costs and subjects' use of other health and social services were also investigated. RESULTS: At 6 months, 586 subjects completed the MADRS questionnaire. There was a significant difference (P=0.025) in mean MADRS scores: 14.3 (Group I); 14.9 (Group II); 16.8 (Group III), using analysis of covariance. Response (40% improvement) rates were 60.2% for Sertraline alone, 46.6% for IPT alone, and 57.5% for Sertraline augmented by IPT (P=0.02). At 2 years, 525 subjects were retained for follow-up. There was no statistically significant difference between Sertraline alone and Sertraline plus IPT in symptom reduction. However, both were more effective than IPT alone in reducing depressive symptoms (P=0.03). There was a statistically significant difference between groups in costs for use of health and social services. The IPT treatment groups had the lower costs for use of health and social services. CONCLUSIONS: Sertraline or Sertraline plus IPT was more effective than IPT alone after 6 months. Over the long term (2 years), all three treatments provide reasonably effective treatment for reducing symptoms of dysthymia, but Sertraline or combining Sertraline with IPT is more effective than IPT alone. Of these two more effective treatments, subjects in the Sertraline plus IPT group had less health and social service costs by $480 per person over 2 years. These findings underscore the effects of combining pharmacotherapy and psychotherapy and the economic value of this more comprehensive treatment of dysthymia in primary care. 相似文献
959.
CD4(+)CD25(+) immunoregulatory T cells: gene expression analysis reveals a functional role for the glucocorticoid-induced TNF receptor 总被引:77,自引:0,他引:77
McHugh RS Whitters MJ Piccirillo CA Young DA Shevach EM Collins M Byrne MC 《Immunity》2002,16(2):311-323
CD4(+)CD25(+) immunoregulatory T cells represent a unique lineage of thymic-derived cells that potently suppress both in vitro and in vivo effector T cell function. We analyzed CD4(+)CD25(+) and CD4(+)CD25(-) T cells by DNA microarray, identifying 29 genes differentially expressed in the resting subpopulations, and 77 that were differentially expressed following activation. Most of these genes were elevated in the CD4(+)CD25(+) population, suggesting a previously activated phenotype. Among these were a number of genes that antagonize signaling, including members of the SOCS family, which may contribute to their anergic phenotype. Multiple cell surface receptors also had increased expression in CD4(+)CD25(+) cells, including GITR, a member of the TNF receptor superfamily. Importantly, antibodies to GITR abrogated suppression, demonstrating a functional role for this receptor in regulating the CD4(+)CD25(+) T cell subset. 相似文献
960.
The metamorphosis of abdominal aortic aneurysm (AAA) repair from open surgical to endovascular means has evolved substantially over the past 2 decades.Today,endovascular abdominal aneurysm repair (EVAR)is considered as the first choice of therapy for treatment of infrarenal AAA in patients with favorable morphology.Furthermore,in "real world" clinical scenarios,with increasing physician experience and ability,the indications of EVAR have expanded from treatment of elective to emergent aneurysms and from favorable morphology to sometimes complex and unfavorable anatomy,particularly in high-risk patients.1-4 When considering these endovascular techniques for treating ruptured AAA,one has to prepare for the challenges of streamlining patient care from the emergency room to the operating room and subsequent endovascular procedure that often requires a multidisciplinary approach and a change in paradigm and local cultures.This paper will focus on a comprehensive and standardized technical approach for treating patients presenting with ruptured AAA by endovascular means that can maximize our ability to offer this treatment of most patients and optimize outcomes. 相似文献