| 1. |
- Blennow, Kaj, 1958, et al.
(författare)
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No association between the alpha2-macroglobulin (A2M) deletion and Alzheimer's disease, and no change in A2M mRNA, protein, or protein expression.
- 2000
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Ingår i: Journal of neural transmission (Vienna, Austria : 1996). - : Springer Science and Business Media LLC. - 0300-9564 .- 1435-1463. ; 107:8-9, s. 1065-79
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Tidskriftsartikel (refereegranskat)abstract
- A polymorphism consisting of a deletion near the 5' splice site of exon 18 on the alpha2-macroglobulin (A2M) gene (A2M-2) has been suggested to be associated with Alzheimer's disease (AD) in family-based studies. We studied the A2M-2 allele together with the ApoE alleles in a large series on patients with AD (n = 449) and age-matched controls (n = 349). Neuropathologically confirmed diagnoses were available in 199 cases (94 AD and 107 control cases). We found no increase in A2M-2 genotype or allele frequencies in AD (27.5% and 14.6%) versus controls (26.4% and 14.9%). In contrast, a marked increase (p < 0.0001) in ApoE epsilon4 genotype or allele frequencies was found in AD (66.6% and 41.2%) as compared with controls (29.8% and 16.5%), suggesting sufficient statistical power in our sample. No relation was found between the A2M-2 and the ApoE epsilon4 allele. No change in A2M exon 17-18 mRNA size or sequence or A2M protein size was found in cases carrying the A2M-2 deletion, suggesting that there is no biological consequences of the A2M intronic deletion. No change in A2M protein level in cerebrospinal fluid was found in AD, suggesting that the A2M-2 allele does not effect the A2M protein expression in the brain. The lack of an association between the A2M-2 allele and AD in the present study, and the lack of abnormalities in the A2M mRNA or protein suggest that the A2M-2 allele is not associated with AD.
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| 2. |
- Fors, Andreas, 1977, et al.
(författare)
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Effects of a person-centred telephone-support in patients with chronic obstructive pulmonary disease and/or chronic heart failure - A randomized controlled trial
- 2018
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13:8
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Tidskriftsartikel (refereegranskat)abstract
- To evaluate the effects of person-centred support via telephone in two chronically ill patient groups, chronic obstructive pulmonary disease (COPD) and/or chronic heart failure (CHF). 221 patients ≥ 50 years with COPD and/or CHF were randomized to usual care vs. usual care plus a person-centred telephone-support intervention and followed for six months. Patients in the intervention group were telephoned by a registered nurse initially to co-create a person-centred health plan with the patient and subsequently to discuss and evaluate the plan. The primary outcome measure was a composite score comprising General Self-Efficacy (GSE), re-hospitalization and death. Patients were classified as deteriorated if GSE had decreased by ≥ 5 points, or if they had been re-admitted to hospital for unscheduled reasons related to COPD and/or CHF or if they had died. At six-month follow-up no difference in the composite score was found between the two study groups (57.6%, n = 68 vs. 46.6%, n = 48
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| 3. |
- Grauers Wiktorin, Hanna, 1990, et al.
(författare)
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Mutated NPM1 in combination with overexpression of Meis1 or Hoxa9 is not sufficient to induce acute myeloid leukemia
- 2016
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Ingår i: Experimental Hematolgy & Oncology. - : Springer Science and Business Media LLC. - 2162-3619. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Background: Acute myeloid leukemia (AML) carrying nucleophosmin 1 (NPM1) mutations (NPMc(+)) is regarded as a separate entity of myeloid neoplasms due to its distinct biological and clinical features. However, NPMc(+) alone displays low leukemogenic activity and cooperating events appear crucial for AML to develop. Dysregulation of homeobox genes, such as HOXA9 and MEIS1, is a common transcriptional signature of NPMc(+) AML. Furthermore, the pathogenic role for NPMc(+) in AML remains incompletely understood. Aim: To elucidate if NPMc(+) collaborates with Meis1 or Hoxa9 in the evolvement of AML. Methods: Murine bone marrow cells were genetically engineered to express mutated NPM1 variant A in combination with overexpression of Meis1 or Hoxa9. The capacity of the transduced cells to transform in vitro and to cause leukemia in vivo was then assessed. Findings and conclusion: There was no synergy between NPMc(+) and Meis1 or Hoxa9 in causing leukemogenic transformation of murine bone marrow cells, or in inducing AML in a transplantation model. Hence, overexpression of Meis1 or Hoxa9 in combination with NPMc(+) expression was not sufficient to generate an NPMc(+) AML mouse model.
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| 4. |
- Jansson, Ann, 1950, et al.
(författare)
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Activity of the LMP1 gene promoter in Epstein-Barr virus-transformed cell lines is modulated by sequence variations in the promoter-proximal CRE site.
- 2007
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Ingår i: The Journal of general virology. - : Microbiology Society. - 0022-1317 .- 1465-2099. ; 88:Pt 7, s. 1887-94
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Tidskriftsartikel (refereegranskat)abstract
- The Epstein-Barr virus (EBV)-encoded tumour-associated latent membrane protein 1 (LMP1) gene expression is transactivated by EBV nuclear antigen 2 (EBNA2) in human B cells. We have previously identified a cyclic AMP-responsive element (CRE) in the B95-8 LMP1 promoter that is essential for transcription activation. Sequencing of LMP1 promoter in the P3HR1-derived EREB2.5 cell line revealed 25 single base pair substitutions in comparison to the B95-8 virus, one of them localized in the CRE element. Sequence variations in this element have been identified in several EBV isolates of both African and Asian origins. The effect of the P3HR1 CRE site variation on binding of factors to the LMP1 promoter sequence (LRS) and promoter activation was investigated with electrophoretic mobility-shift assays and reporter gene transfection assays. ATF1 and CREB1 transcription factors bound with reduced efficiency to the P3HR1 variant and below the detection level to the other tested variants. Accordingly, reporter plasmids carrying the P3HR1 CRE sequence in a B95-8 LRS context displayed 50 % lower activity in all tested cell lines. The impaired ability to activate transcription caused by the C to A substitution in CRE was not apparent when the mutated site was placed in a P3HR1 LRS context and the reporter transfected into Jijoye cells, most likely as a consequence of the other base pair substitutions in P3HR1 LRS. Overall, our results suggest that the mutations in the LRS CRE site have been conserved to adjust LMP1 expression to levels that favour cell survival in certain cellular and environmental contexts.
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| 5. |
- Jansson, Ann, 1950, et al.
(författare)
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Role of a consensus AP-2 regulatory sequence within the Epstein-Barr Virus LMP1 promoter in EBNA2 mediated transactivation
- 2007
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Ingår i: Virus Genes. - : Springer Science and Business Media LLC. - 0920-8569 .- 1572-994X. ; 35:2, s. 203-14
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Tidskriftsartikel (refereegranskat)abstract
- The Epstein-Barr virus (EBV) tumor-associated latent membrane protein 1 (LMP1) gene expression is transactivated by EBV nuclear antigen 2 (EBNA2) in human B cells. We previously reported that an E-box element at the LMP1 regulatory sequence (LRS) represses transcription of the LMP1 gene through the recruitment of a Max-Mad1-mSin3A complex. In the present study, using deletion/mutation analysis, and electrophoretic mobility shift assays, we show that the promoter region adjacent to the E-box (-59/-67) is required for the full repression conferred by E-box binding proteins. The repressive effect of these factors was overcome by an inhibitor of histone deacetylation, Trichostatin A (TSA), concurring with the reports that histone deacetylation plays an important role in repression mediated by Max-Mad1-mSin3A complex. Furthermore, ChIP analyses showed that histones at the transcriptionally active LMP1 promoter were hyperacetylated, whereas in the absence of transcription they were hypoacetylated. EBNA2 activation of the promoter required a consensus AP-2 sequence in the -103/-95 LRS region. While EMSA results and the low level of AP-2 factors expression in B cells argue against known AP-2 factors binding to this site, several pieces of evidence point to a similar mechanism of promoter activation as seen by AP-2 factors. We conclude that an AP-2 site-binding factor and EBNA2 act in concert to overcome the repression of the LMP1 promoter via the consensus AP-2 site. This activation showed strong correlation with histone hyperacetylation at the promoter, indicating this to be a major mechanism for the EBNA2 mediated LMP1 transactivation.
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| 6. |
- Johansson, Pegah, 1978, et al.
(författare)
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Nuclear factor-kappaB binds to the Epstein-Barr Virus LMP1 promoter and upregulates its expression.
- 2009
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Ingår i: Journal of virology. - 1098-5514. ; 83:3, s. 1393-401
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Tidskriftsartikel (refereegranskat)abstract
- The latent membrane protein 1 (LMP1) oncogene carried by Epstein-Barr virus (EBV) is essential for transformation and maintenance of EBV-immortalized B cells in vitro, and it is expressed in most EBV-associated tumor types. The activation of the NF-kappaB pathway by LMP1 plays a critical role in the upregulation of antiapoptotic proteins. The EBV-encoded EBNA2 transactivator is required for LMP1 activation in latency III, while LMP1 itself appears to be critical for its activation in the latency II gene expression program. In both cases, additional viral and cellular transcription factors are required in mediating transcription activation of the LMP1 promoter. Using DNA affinity purification and chromatin immunoprecipitation assay, we showed here that members of the NF-kappaB transcription factor family bound to the LMP1 promoter in vitro and in vivo. Electrophoretic mobility shift assay analyses indicated the binding of the p50-p50 homodimer and the p65-p50 heterodimer to an NF-kappaB site in the LMP1 promoter. Transient transfections and reporter assays showed that the LMP1 promoter is activated by exogenous expression of NF-kappaB factors in both B cells and epithelial cells. Exogenous expression of NF-kappaB factors in the EBNA2-deficient P3HR1 cell line induced LMP1 protein expression. Overall, our data are consistent with the presence of a positive regulatory circuit between NF-kappaB activation and LMP1 expression.
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| 7. |
- Johansson, Pegah, 1978, et al.
(författare)
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The p38 signaling pathway upregulates expression of the Epstein-Barr virus LMP1 oncogene.
- 2010
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Ingår i: Journal of virology. - 1098-5514. ; 84:6, s. 2787-97
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Tidskriftsartikel (refereegranskat)abstract
- The Epstein-Barr virus (EBV)-encoded LMP1 oncogene has a role in transformation, proliferation, and metastasis of several EBV-associated tumors. Furthermore, LMP1 is critically involved in transformation and growth of EBV-immortalized B cells in vitro. The oncogenic properties of LMP1 are attributed to its ability to upregulate anti-apoptotic proteins and growth signals. The transcriptional regulation of LMP1 is dependent on the context of cellular and viral proteins present in the cell. Here, we investigated the effect of several signaling pathways on the regulation of LMP1 expression. Inhibition of p38 signaling, using p38-specific inhibitors SB203580 and SB202190, downregulated LMP1 in estrogen-induced EREB2.5 cells. Similarly, p38 inhibition decreased trichostatin A-induced LMP1 expression in P3HR1 cells. Exogenous expression of p38 in lymphoblastoid cell lines (LCLs) led to an increase in LMP1 promoter activity in reporter assays, and this activation was mediated by the previously identified CRE site in the promoter. Inhibition of p38 by SB203580 and p38-specific small interfering RNA (siRNA) also led to a modest decrease in endogenous LMP1 expression in LCLs. Chromatin immunoprecipitation indicated decreased binding of CREB-ATF1 to the CRE site in the LMP1 promoter after inhibition of the p38 pathway in EREB2.5 cells. Taken together, our results suggest that an increase in p38 activation upregulates LMP1 expression. Since p38 is activated in response to stimuli such as stress or possibly primary infection, a transient upregulation of LMP1 in response to p38 may allow the cells to escape apoptosis. Since the p38 pathway itself is activated by LMP1, our results also suggest the presence of an autoregulatory loop in LMP1 upregulation.
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| 8. |
- Larsson, Lena, 1969, et al.
(författare)
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The Sp1 transcription factor binds to the G-allele of the -1087 IL-10 gene polymorphism and enhances transcriptional activation.
- 2009
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Ingår i: Genes and immunity. - : Springer Science and Business Media LLC. - 1466-4879 .- 1476-5470. ; 10, s. 280-284
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Tidskriftsartikel (refereegranskat)abstract
- The objectives of this study were to evaluate the influence of the -1087 single nucleotide polymorphism (SNP) on the gene expression of interleukin (IL)-10 and to identify transcription factors binding to this site in B cells. Using electrophoretic mobility-shift assays and nuclear extract from the DG75 B-cell line, we demonstrated that the Sp1 transcription factor bound to the -1087 G-allele of the IL-10 promoter and that the transcription factors PU.1 and Spi-B bound to both the G- and A-alleles. Transient transfections showed that lipopolysaccharide stimulation resulted in a 15-fold increase in promoter activity for the G-allele as compared to a 6-fold increase for the A-allele. Co-transfection with Sp1 expression vector in Sp1-deficient SL2 cells leading to Sp1 binding to the G-allele of the -1087 SNP resulted in increased IL-10 promoter activity. The results suggest a role for Sp1 transcription factor in the activation of IL-10 through the G-allele of the -1087 SNP in response to inflammatory signals.Genes and Immunity advance online publication, 9 October 2008; doi:10.1038/gene.2008.79.
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| 9. |
- Sjöblom-Hallén, A, et al.
(författare)
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An ATF/CRE element mediates both EBNA2-dependent and EBNA2-independent activation of the Epstein-Barr virus LMP1 gene promoter.
- 1998
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Ingår i: Journal of virology. - 0022-538X. ; 72:2, s. 1365-76
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Tidskriftsartikel (refereegranskat)abstract
- The Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) is a viral oncogene whose expression is regulated by both viral and cellular factors. EBV nuclear antigen 2 (EBNA2) is a potent transactivator of LMP1 expression in human B cells, and several EBNA2 response elements have been identified in the promoter regulatory sequence (LRS). We have previously shown that an activating transcription factor/cyclic AMP response element (ATF/CRE) site in LRS is involved in EBNA2 responsiveness. We now establish the importance of the ATF/CRE element by mutational analysis and show that both EBNA2-dependent activation and EBNA2-independent activation of the promoter occur via this site but are mediated by separate sets of factors. An electrophoretic mobility shift assay (EMSA) with specific antibodies showed that the ATF-1, CREB-1, ATF-2 and c-Jun factors bind to the site as ATF-1/CREB-1 and ATF-2/c-Jun heterodimers whereas the Sp1 and Sp3 factors bind to an adjacent Sp site. Overexpression of ATF-1 and CREB-1 in the cells by expression vectors demonstrated that homodimeric as well as heterodimeric forms of the factors transactivate the LMP1 promoter in an EBNA2-independent manner. The homodimers of ATF-2 and c-Jun did not significantly stimulate promoter activity. In contrast, the ATF-2/c-Jun heterodimer had only a minor stimulatory effect in the absence of EBNA2 but induced a strong transactivation of the LMP1 promoter when coexpressed with this protein. Evidence for a direct interaction between the ATF-2/c-Jun heterodimeric complex and EBNA2 was obtained by EMSA and coimmunoprecipitation experiments. Thus, our results suggest that EBNA2-induced transactivation via the ATF/CRE site occurs through a direct contact between EBNA2 and an ATF-2/c-Jun heterodimer. EBNA2-independent promoter activation via this site, on the other hand, is mediated by a heterodimeric complex between the ATF-1 and CREB-1 factors.
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| 10. |
- Staffas, Anna, 1982, et al.
(författare)
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Upregulation of Flt3 is a passive event in Hoxa9/Meis1-induced acute myeloid leukemia in mice.
- 2017
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Ingår i: Oncogene. - : Springer Science and Business Media LLC. - 1476-5594 .- 0950-9232. ; 36, s. 1516-1524
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Tidskriftsartikel (refereegranskat)abstract
- HOXA9, MEIS1 and FLT3 are genes frequently upregulated in human acute myeloid leukemia. Hoxa9 and Meis1 also cooperate to induce aggressive AML with high Flt3 expression in mice, suggesting an important role for Flt3 in Hoxa9/Meis1-induced leukemogenesis. To define the role of Flt3 in AML with high Hoxa9/Meis1, we treated mice with Hoxa9/Meis1-induced AML with the Flt3 inhibitor AC220, used an Flt3-ligand (FL-/-) knockout model, and investigated whether overexpression of Flt3 could induce leukemia together with overexpression of Hoxa9. Flt3 inhibition by AC220 did not delay AML development in mice transplanted with bone marrow cells overexpressing Hoxa9 and Meis1. In addition, Hoxa9/Meis1 cells induced AML in FL-/- mice as rapid as in wild-type mice. However, FL-/- mice had reduced organ infiltration compared with wild-type mice, suggesting some Flt3-dependent effect on leukemic invasiveness. Interestingly, leukemic Hoxa9/Meis1 cells from sick mice expressed high levels of Flt3 regardless of presence of its ligand, showing that Flt3 is a passive marker on these cells. In line with this, combined engineered overexpression of Flt3 and Hoxa9 did not accelerate the progression to AML. We conclude that the Hoxa9- and Meis1-associated upregulation of Flt3 is not a requirement for leukemic progression induced by Hoxa9 and Meis1.Oncogene advance online publication, 12 September 2016; doi:10.1038/onc.2016.318.
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