bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of family history, obesity and exercise on breast cancer risk among postmenopausal women
Authors: Carpenter Catherine L. , Ross Ronald K. , Paganini‐Hill Annlia , Bernstein Leslie 
Published: June 2003

AbstractWe examined effects of obesity and lifetime exercise patterns on postmenopausal breast cancer risk according to family history in a large population‐based case control study conducted in Los Angeles County, California, because we hypothesized that both factors would affect risk through similar mechanistic pathways, and that their effects would be stronger among women with a family history. We studied 1,883 postmenopausal breast cancer case subjects and 1,628 postmenopausal control subjects ranging in age from 55–72 years. Cases were diagnosed with incident breast cancer in the late 1980s and 1990s. Controls were individually matched to case subjects on age, ethnic origin and neighborhood. In‐person interviews determined known breast cancer risk factors including: height, weight, lifetime exercise, and family history of breast and other cancers. Breast cancer risk was raised among women who had at least 1 first‐degree relative with breast cancer (odds ratio [OR] = 1.68; 95% confidence interval [CI] = 1.36–2.08). Risk increased with increasing levels of body‐mass index (wt‐kg/ht‐m2) (p‐trend = 0.005). Breast cancer risk was reduced among women who maintained, on average, 17.6 metabolic equivalent of energy expenditure (MET)‐hr of activity/week from menarche onward (OR = 0.66; 95% CI = 0.48–0.90). Body‐mass index, adjusted for lifetime exercise, was strongly associated with breast cancer risk among women with a positive family history of breast cancer (p‐trend < 0.0001), but only weakly associated among women with no family history (p‐trend = 0.08; homogeneity of trends p = 0.0005). In contrast, the risk reduction associated with exercise activity, adjusting for body‐mass index, was limited to women without a family history of breast cancer (p‐trend = 0.001; homogeneity of trends p = 0.005). Body‐mass index and exercise activity, both modifiable risk factors for breast cancer, seem to have differential effects depending on a woman's family history of breast cancer, and may impact risk through different biological mechanisms. © 2003 Wiley‐Liss, Inc.
Expression profiles of angiogenic growth factors in squamous cell carcinomas of the head and neck
Authors: Ninck Simon , Reisser Christoph , Dyckhoff Gerhard , Helmke Burkhard , Bauer Harald , Herold‐Mende Christel 
Published: June 2003

AbstractInhibition of angiogenesis by blocking angiogenic cytokines or their pathways has become a major target in experimental cancer therapies. This therapeutical approach requires a profound knowledge of growth factor profiles that contribute to tumor growth and progression. The respective knowledge is presently rather incomplete for head and neck squamous cell carcinomas (HNSCC). Therefore we studied expression of several angiogenic cytokines including VEGF, bFGF, PDGF‐AB, PDGF‐BB, G‐CSF and GM‐CSF in HNSCC in vivo and in vitro. In tumor tissues expression of all cytokines was observed albeit with marked differences concerning intensity and distribution pattern. Quantification of the cytokines in the supernatant of 15 tissue‐corresponding HNSCC cultures revealed that VEGF, PDGF‐AB and less frequently GM‐CSF were secreted in high amounts of up to 13 ng/ml/106 cells. Twenty percent of the HNSCC cultures expressed only 1 cytokine in biologically active amounts, 60% 2 or 3 and 20% expressed the maximum of 4 cytokines simultaneously. Interestingly, we observed a distinct cytokine pattern: HNSCC cells secreting only 1 or 2 cytokines presented always with either VEGF and/or PDGF‐AB, while G‐CSF and GM‐CSF were secreted primarily together with VEGF and PDGF‐AB. The number of cytokines expressed by HNSCC cells correlated with the microvessel density of the original tumor and with the clinical outcome: tumors producing at least 3 cytokines revealed a significantly poorer patient prognosis. Our data indicate a major role for VEGF and PDGF‐AB in HNSCC and that the additional secretion of G‐CSF or GM‐CSF might contribute to a poorer prognosis in patients suffering from these tumors. © 2003 Wiley‐Liss, Inc.
Circulating levels of insulin‐like growth factor I, its binding proteins ‐1,‐2, ‐3, C‐peptide and risk of postmenopausal breast cancer
Authors: Keinan‐Boker Lital , Bueno de Mesquita H. Bas , Kaaks Rudolf , van Gils Carla H. , van Noord Paul A.H. , Rinaldi Sabina , Riboli Elio , Seidell Jaap C. , Grobbee Diederick E. , Peeters Petra H.M. 
Published: June 2003

AbstractHigher levels of circulating Insulin‐like Growth Factor (IGF)‐I may be associated with higher risks for premenopausal breast cancer. We investigate the associations between circulating levels of IGF‐I, its binding proteins (IGFBPs) ‐1, ‐2, ‐3, C‐peptide and postmenopausal breast cancer. This is a prospective study nested in 2 Dutch cohorts. The study population included women who were postmenopausal at baseline. Breast cancer cases were identified through linkage with cancer registries. Controls were matched to cases by cohort, age, date of blood donation and place of residence. In total, 149 breast cancer cases and 333 healthy controls were included. Plasma levels of IGF‐I, IGFBP‐1, ‐2, ‐3 and C‐peptide were measured by radioimmunoassays. Estimates of the relative risk for breast cancer associated with the quartiles of the peptides' circulating levels were obtained by conditional logistic regression. Models were adjusted for BMI, age at menarche and age at first full‐term delivery. For IGF‐I, the adjusted OR (95% CI) of the top vs. bottom quartile was 1.1 (0.6; 2.1); for IGFBP‐1 it was 0.7 (0.3; 1.3); for IGFBP‐2, 1.1 (0.5; 2.4); for IGFBP‐3, 1.6 (0.7; 3.5), for C‐peptide, 1.3 (0.7; 2.7) and for IGF‐I/IGFBP‐3 ratio, 1.0 (0.5; 1.8). Our data do not support an association between postmenopausal circulating levels of IGF‐I, IGFBP‐1, ‐2, ‐3, C‐peptide and postmenopausal breast cancer. © 2003 Wiley‐Liss, Inc.
Target selection for antisense oligonucleotide induced exon skipping in the dystrophin gene
Authors: Errington Stephen J. , Mann Christopher J. , Fletcher Sue , Wilton Stephen D. 
Published: June 2003

AbstractBackgroundDuchenne muscular dystrophy (DMD) is an X‐linked recessive muscle wasting disorder characterised by the absence of the protein dystrophin. Antisense oligonucleotides have been used to re‐direct dystrophin pre‐mRNA processing by blocking sequences crucial to pre‐mRNA splicing, thereby inducing skipping of specific exons. We wished to determine which splicing motifs are most amenable as targets for antisense oligonucleotide induction of efficient and specific skipping of selected exons.MethodsAntisense oligonucleotides were directed at regions of dystrophin exon 19 involved in pre‐mRNA splicing, including the donor and acceptor splice sites and the exon splicing enhancer (ESE). Cultured myotubes were transfected with antisense oligonucleotides at various concentrations and studies undertaken to determine both specificity and efficiency of induced exon 19 skipping.ResultsAntisense oligonucleotides as small as 12 nucleotides targeting the ESE induced consistent and specific skipping of only exon 19 in both human and normal and mdx mouse myotubes. Antisense oligonucleotides directed at the donor and acceptor splice sites also induced specific exon 19 skipping while mismatched antisense oligonucleotides could only induce skipping when delivered at higher concentrations. No other dystrophin exons were removed from the mature mRNA as a consequence of these antisense oligonucleotides treatments.ConclusionsAntisense oligonucleotides directed at the ESE tended to be marginally more efficient than those which targeted the donor or acceptor splice sites, based on their ability to induce specific skipping at lower concentrations. The specificity of exon removal does not appear to be a function of target selection, but may reflect the combination of the splicing motifs and position of that exon in the pre‐mRNA. Copyright © 2003 John Wiley & Sons, Ltd.
Sustained tetracycline‐regulated transgene expression in vivo in rat retinal ganglion cells using a single type 2 adeno‐associated viral vector
Authors: Folliot Sebastien , Briot Delphine , Conrath Hervé , Provost Nathalie , Cherel Yan , Moullier Philippe , Rolling Fabienne 
Published: June 2003

AbstractBackgroundViral vector delivery of neurotrophic‐expressing transgenes in the retina may retard or prevent the onset of blindness associated with photoreceptor degeneration. A key safety issue is to achieve regulated expression of these genes in the retina. The purpose of our study was to evaluate whether a single recombinant AAV‐2 (rAAV) encoding for a tetracycline (Tet)‐regulated destabilized reporter gene could provide quantitative profiles of gene regulation targeted to the rat neuroretina.MethodsA rAAV vector carrying a destabilized green fluorescent protein (dgfp) under a tet‐regulatable promoter and the tetracycline‐repressed transactivator (tTA) was generated (rAAVtetoff.dgfp) and administered intravitreally in nine Wistar rats. Retinas were monitored for 6 months using noninvasive fluorescence imaging and the animals were subjected to two cycles of doxycycline (Dox), a tetracycline analog. Eyes were ultimately examined by histology.ResultsIntravitreal injection of rAAVtetoff.dgfp resulted in effective transduction of ganglion cells. Following full expression of the transgene in the absence of Dox, 95% of the GFP signal was shut down 48 h post Dox administration and the signal was undetectable 7 days later. Initial levels of GFP expression were restored 21 days after Dox administration ceased. This pattern of expression was repeated twice over a period of 6 months.ConclusionsThis report demonstrates that rAAVtetoff.dgfp intravitreally injected rats displayed tight and sustained long‐term regulation of the reporter gene in ganglion cells. These findings may have important implications regarding rAAV‐mediated gene therapy using neuroprotective approaches for retinitis pigmentosa and glaucoma. Copyright © 2003 John Wiley & Sons, Ltd.
Sustained transgene expression in cartilage defects in vivo after transplantation of articular chondrocytes modified by lipid‐mediated gene transfer in a gel suspension delivery system
Authors: Madry Henning , Cucchiarini Magali , Stein Ute , Remberger Klaus , Menger Michael D. , Kohn Dieter , Trippel Stephen B. 
Published: June 2003

AbstractBackgroundGenetically modified chondrocytes may be able to modulate articular cartilage repair. To date, transplantation of modified chondrocytes into cartilage defects has been restricted to viral vectors. We tested the hypothesis that a recombinant gene can be delivered to sites of cartilage damage in vivo using chondrocytes transfected by a lipid‐mediated gene transfer method.MethodsIsolated lapine articular chondrocytes were transfected with an expression plasmid vector carrying the P. pyralis luciferase gene using the reagent FuGENE 6. Transfected chondrocytes were encapsulated in alginate spheres and implanted into osteochondral defects in the knee joints of rabbits.ResultsIn vitro, luciferase activity in pCMVLuc‐transfected spheres showed an early peak at day 2 post‐transfection and remained elevated at day 32, the longest time point evaluated. The number of viable chondrocytes in non‐transfected and transfected spheres increased over the period of cultivation. In vivo, luciferase activity was maximal at day 5 post‐transfection, declined by day 16, but was still present at day 32. On histological analysis, the alginate‐chondrocyte spheres filled the cartilage defects and were surrounded by a fibrous repair tissue composed of spindle‐shaped cells.ConclusionsThese data demonstrate the successful introduction of articular chondrocytes modified by lipid‐mediated gene transfer in a gel suspension delivery system into osteochondral defects and the sustained expression of the transgene in vivo. This method may be used to define the effects of genes involved in cartilage repair and may provide alternative treatments for articular cartilage defects. Copyright © 2003 John Wiley & Sons, Ltd.
Augmented antitumor activity of a secondary lymphoid‐tissue chemokine (SLC)‐interleukin (IL) 2 fusion protein in mouse
Authors: Nakahara Koichiro , Sakata Tsuneaki 
Published: June 2003

AbstractBackgroundTo enhance the antitumor efficacy of IL2 gene therapy, combinations of several other genes, such as p53, a tumor suppressor gene, or lymphotactin, a C‐chemokine, and the IL2 gene are attempted, and synergistic effects are observed. We report here on the enhanced antitumor activity of a fusion protein (mSLC‐IL2) comprised of a newly identified member of the CC‐chemokine family, mouse SLC (mSLC), and mouse IL2 (mIL2).MethodsWe constructed mSLC‐IL2 by connecting the N‐terminus of mIL‐2 to the C‐terminus of mSLC using a two‐amino‐acid linker. The resultant fusion protein retained both mIL2 activity, as measured in a standard proliferation assay using a mouse IL‐2 dependent cell line, and chemokine activity, as measured in a chemotaxis assay using a preB cell line expressing mSLC‐specific receptor, CCR7. The gene encoding mSLC‐IL2 was retrovirally transduced into fibroblast CL.7 cells, derived from Balb/c mice.ResultsIntradermal transplantation of fibroblasts expressing mSLC‐IL2 into syngenic mice induced a dense accumulation of CD4+ and CD8+ cells at the sites of transplantation. Moreover, when CT‐26 cells, derived from colon adenocarcinoma cells, were co‐transplanted with mSLC‐IL2‐transduced fibroblasts, the CT‐26 cell exhibited significantly lower tumorigenicity than CT‐26 cells co‐transplanted with mIL2‐transduced fibroblasts.ConclusionsThese findings, obtained from both in vitro and in vivo data, suggest that the gene encoding mSLC‐IL2 may be a good candidate for inclusion as part of an anticancer gene therapy protocol. Copyright © 2003 John Wiley & Sons, Ltd.
Electroporation‐mediated ex vivo gene transfer into graft not requiring injection pressure in orthotopic liver transplantation
Authors: Kobayashi Shogo , Dono Keizo , Takahara Shiro , Isaka Yoshitaka , Imai Enyu , Zhenhui Lu , Nagano Hiroaki , Tomoaki Kato , Umeshita Koji , Nakamori Shoji , Sakon Masato , Monden Morito 
Published: June 2003

AbstractBackgroundWe investigated optimum conditions for ex vivo gene transfer into liver grafts by plasmid injection via the portal vein combined with electroporation in rat liver transplantation.MethodsAnesthetized 9‐week‐old male Shionogi‐Wistar rats were used as donors and recipients. After harvest of the liver graft from the donor rat, a tapered 3Fr. catheter was inserted into the portal vein of the liver graft ex vivo. After clamping the afferent vessels around the right and caudal liver lobes, pCAGGS‐luciferase, which was diluted with one of several osmotic pressure solutions, or pCAGGS‐green fluorescence protein (GFP) plasmid was injected into these lobes to keep the efferent vessels patent. Electrical pulses were applied to the liver graft during cold preservation in lactated Ringer's solution, University of Wisconsin solution, and histidine‐tryptophan‐ketoglutarate solution.ResultsTransfection efficacy was estimated by measurement of luciferase activity. Luciferase activity in the liver was dependent on both the voltage and electric current of the electrical pulse, and also on the type of preservation solution and plasmid osmotic pressure. Luciferase activity was noted only in plasmid‐injected lobes of the liver graft. GFP‐transfected cells were identified by GFP fluorescence. GFP was observed predominantly in perivascular cells, including hepatocytes.ConclusionsWe have demonstrated successful ex vivo gene transfection into liver grafts without injection pressure by using a non‐viral method. Copyright © 2003 John Wiley & Sons, Ltd.
Effects of adenovirus‐mediated SV5 fusogenic glycoprotein expression on tumor cells
Authors: Gómez‐Treviño A. , Castel S. , López‐Iglesias C. , Cortadellas N. , Comas‐Riu J. , Mercadé E. 
Published: June 2003

AbstractBackgroundThe fusogenic (F) membrane glycoprotein of the paramyxovirus SV5 allows virus to enter host cells and mediates fusion between neighboring cells, which leads to cell death. F glycoprotein is synthesized as an inactive precursor (F0) that is cleaved by cellular protease furine to form the active heterodimer F1 + F2. The active protein can induce syncytium formation in the absence of another integral glycoprotein (HN), a property that appears to be unique among paramyxoviruses.MethodologyWe constructed a non‐replicative adenovirus to express SV5 F protein in tumor cells, and its fusion capacity was analyzed by fluorescent and confocal microscopy. Cell viability and bystander effect were compared with the thymidine kinase/ganciclovir suicide gene therapy. The structure of F‐expressing cells was studied using electron microscopy.ResultsF glycoprotein expression induced syncytium formation to a maximum at 72 h, after which syncytia progressively lost viability and detached. The cell membrane was disrupted while nuclear structure was preserved. Over‐expression of SV5 F protein in tumor cells led to high cytotoxicity comparable with that associated with the thymidine kinase/ganciclovir. A potent bystander killing effect was detected until the ratio of F‐transduced to non‐transduced cells was 1 : 100.ConclusionsThese results indicate that the fusogenic glycoprotein of the paramyxovirus SV5 could be used to eliminate tumor cells and may encourage studies aimed at modifying its selectivity and combining its expression with other cytotoxic strategies to improve their efficacy. Copyright © 2003 John Wiley & Sons, Ltd.
Aspartylglucosaminidase (AGA) is efficiently produced and endocytosed by glial cells: implication for the therapy of a lysosomal storage disorder
Authors: Harkke Salli , Laine Minna , Jalanko Anu 
Published: June 2003

AbstractBackgroundAspartylglucosaminuria (AGU) represents diseases affecting the central nervous system and is caused by a deficiency of a lysosomal enzyme, aspartylglucosaminidase (AGA). AGA, like lysosomal enzymes in general, are good targets for gene therapy since they move from cell to cell using the mannose‐6‐phosphate receptor. Consequently, only a minority of target cells need to be corrected. Here, we wanted to determine which cell type, neurons or glia would better produce AGA to be transported to adjacent cells for use in possible treatment strategies.MethodsAdenoviruses containing tissue‐specific glial fibrillary acidic protein (GFAP) promoter and neuron‐specific enolase (NSE) promoter were generated to target expression of AGA in Aga‐deficient mouse primary glial and neuronal cell cultures. In addition an endogenous AGA promoter was used. The experimental design was planned to measure the enzymatic activities in the cells and media of neurons and glia infected with each specific virus. The endocytosis of AGA was analyzed by incubating neuronal and glial cells with media produced by each virus‐cell combination.ResultsAGA promoter was shown to be a very powerful glia promoter producing 32 times higher specific AGA activity in glia than in neurons. GFAP and NSE promoters also produced a clear overexpression of AGA in glia and neurons, respectively. Interestingly, both the NSE and GFAP promoters were not cell‐specific in our system. The amount of exocytosed AGA was significantly higher in glial cells than neurons and glial cells were also found to have a greater capacity to endocytose AGA.ConclusionsThese data indicate the importance of glial cells in the expression and transport of AGA. Subsequently, new approaches can be developed for therapeutic intervention. Copyright © 2003 John Wiley & Sons, Ltd.
Antisense downregulation of mutant huntingtin in a cell model
Authors: Hasholt Lis , Abell Kathrine , Nørremølle Anne , Nellemann Christine , Fenger Kirsten , Sørensen Sven Asger 
Published: June 2003

AbstractBackgroundHuntington's disease (HD) is an inherited neurodegenerative disorder which is caused by an expansion of a CAG repeat sequence in the HD gene. The repeat encodes an expanded polyglutamine tract in the protein huntingtin. The still unknown pathological mechanisms leading to death of specific neurons in the brains of HD patients correlate with the expression of mutant huntingtin. Therefore, we have studied whether mutant huntingtin expression can be downregulated by antisense technique.MethodsNT2 precursor cells and differentiated postmitotic NT2‐N neurons, respectively, were transfected with plasmid constructs containing exon 1 of the HD gene with expanded CAG repeats in frame with the reporter protein EGFP. The transfected cell cultures were treated with a phosphorothioated antisense oligonucleotide (PS‐ASHD/20+) or a control oligonucleotide either by cotransfection or by addition to the culture medium.ResultsExpression of the fusion protein containing the mutant huntingtin fragment resulted in diffuse green fluorescence in the cytoplasm and formation of aggregates in some of the NT2 cells and NT2‐N neurons. We obtained antisense sequence‐specific inhibition of expression of the fusion protein and/or suppression of the aggregate formation in both cell types. In the NT2 cells the antisense effect was dependent on the way of administration of the oligo.ConclusionsThe PS‐antisense oligo is effective in downregulation of mutant huntingtin, and the reduction of aggregate formation is a sensitive biological marker. The findings suggest that antisense knockdown of huntingtin could be a useful strategy for treatment of HD, and could also be suitable for studies of the normal and pathological function of huntingtin in different cellular model systems. Copyright © 2003 John Wiley & Sons, Ltd.
Adenovirus endocytosis
Authors: Meier Oliver , Greber Urs F. 
Published: June 2003

AbstractPathogen entry into cells occurs by direct penetration of the plasma membrane, clathrin‐mediated endocytosis, caveolar endocytosis, pinocytosis or macropinocytosis. For a particular agent, the infectious pathways are typically restricted, reflecting a tight relationship with the host. Here, we survey the uptake process of human adenovirus (Ad) type 2 and 5 and integrate it into the cell biology of endocytosis. Ad2 and Ad5 naturally infect respiratory epithelial cells. They bind to a primary receptor, the coxsackie virus B Ad receptor (CAR). The CAR‐docked particles activate integrin coreceptors and this triggers a variety of cell responses, including endocytosis. Ad2/Ad5 endocytosis is clathrin‐mediated and involves the large GTPase dynamin and the adaptor protein 2. A second endocytic process is induced simultaneously with viral uptake, macropinocytosis. Together, these pathways are associated with viral infection. Macropinocytosis requires integrins, F‐actin, protein kinase C and small G‐proteins of the Rho family, but not dynamin. Macropinocytosis per se is not required for viral uptake into epithelial cells, but it appears to be a productive entry pathway of Ad artificially targeted to the high‐affinity Fcγ receptor CD64 of hematopoietic cells lacking CAR. In epithelial and hematopoietic cells, the macropinosomal contents are released to the cytosol. This requires viral signalling from the surface and coincides with particle escape from endosomes and infection. It emerges that incoming Ad2 and Ad5 distinctly modulate the endocytic trafficking and disrupt selective cellular compartments. These features can be exploited for effective artificial targeting of Ad vectors to cell types of interest. Copyright © 2003 John Wiley & Sons, Ltd.