| 1. |
- Andersson, Charlotta, et al.
(författare)
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Prognostic significance of specific anti-WT1 IgG antibody level in plasma in patients with ovarian carcinoma
- 2014
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Ingår i: Cancer Medicine. - : Wiley. - 2045-7634. ; 3:4, s. 909-918
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Tidskriftsartikel (refereegranskat)abstract
- Ovarian carcinoma (OC) has a poor prognosis and lack early effective screening markers. Wilm's tumor gene 1 (WT1) is overexpressed in OCs. Therefore, it is of great interest to investigate whether WT1-specific antibody (Ab) measurements in plasma can serve as a biomarker of anti-OC response, and is of importance in relation to patient prognosis. Peripheral blood samples were obtained from a total of 103 women with ovarian tumors with median being 1 day (range 0-48 days) before operation. WT1 IgG Ab levels were evaluated using enzyme-linked immunosorbent assay (ELISA). Immunohistochemical analysis of WT1 protein expression was performed on OC tissue samples. We found that low-WT1 Ab level in plasma was related to improved survival in patients diagnosed at stages III-IV and grade 3 carcinomas. Positive WT1 protein staining on OC tissue samples had a negative impact on survival in the entire cohort, both overall survival (OS) (P = 0.046) and progression-free survival (PFS) (P = 0.006), but not in the serous OC subtype. Combining WT1 IgG Ab levels and WT1 staining, patients with high-WT1 IgG Ab levels in plasma and positive WT1 protein staining in cancer tissues had shorter survival, with a significant association in PFS (P = 0.016). These results indicated that WT1 Ab measurements in plasma and WT1 staining in tissue specimens could be useful as biomarkers for patient outcome in the high-risk subtypes of OCs for postoperative individualized therapy.
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| 2. |
- Andersson, Charlotta, et al.
(författare)
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Reduction in WT1 Gene Expression During Early Treatment Predicts the Outcome in Patients With Acute Myeloid Leukemia
- 2012
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Ingår i: Diagnostic molecular pathology (Print). - : Lippincott Williams & Wilkins. - 1052-9551 .- 1533-4066. ; 21:4, s. 225-233
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Tidskriftsartikel (refereegranskat)abstract
- Wilms tumor gene 1 (WT1) expression has been suggested as an applicable minimal residual disease marker in acute myeloid leukemia (AML). We evaluated the use of this marker in 43 adult AML patients. Quantitative assessment of WT1 gene transcripts was performed using real-time quantitative-polymerase chain reaction assay. Samples from both the peripheral blood and the bone marrow were analyzed at diagnosis and during follow-up. A strong correlation was observed between WT1 normalized with 2 different control genes (beta-actin and ABL1, P < 0.001). WT1 mRNA level at diagnosis was of no prognostic relevance (P > 0.05). A >= 1-log reduction in WT1 expression in bone marrow samples taken < 1 month after diagnosis significantly correlated with an improved overall survival (P = 0.004) and freedom from relapse (P = 0.010) when beta-actin was used as control gene. Furthermore, a reduction in WT1 expression by >= 2 logs in peripheral blood samples taken at a later time point significantly correlated with a better outcome for overall survival (P = 0.004) and freedom from relapse (P = 0.012). This result was achieved when normalizing against both b-actin and ABL1. These results therefore suggest that WT1 gene expression can provide useful information for minimal residual disease detection in adult AML patients and that combined use of control genes can give more informative results.
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| 3. |
- Andersson, Charlotta, 1976-
(författare)
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Significance of Wilms’ tumor gene 1 as a biomarker in acute leukemia and solid tumors
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wilms’ tumor gene 1 (WT1) is a zinc finger transcriptional regulator with crucial functions in embryonic development. Originally WT1 was described as a tumor suppressor gene, but later studies have shown oncogenic properties of WT1 in a variety of tumors. Because of its dual functions in tumorigenesis, WT1 has been described as a chameleon gene. In this thesis, the significance of WT1 as a biomarker was investigated in acute myeloid leukemia (AML), clear cell renal cell carcinoma (ccRCC), ovarian carcinoma (OC) and childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL).Previous studies have suggested that expression of WT1 is a potential marker for detection of minimal residual disease (MRD) in AML. We aimed to define expression of WT1 as an MRD marker in AML. In adult AML patients, we found that a reduction of WT1 expression in bone marrow (≥ 1-log) detected less than 1 month after diagnosis was associated with an improved overall survival (OS) and freedom from relapse (FFR). In peripheral blood, a reduction of WT1 expression (≥ 2-log) detected between 1 and 6 months after treatment initiation was associated with an improved OS and FFR.WT1 harbor pathogenic genetic variants in a considerable proportion of AML and T-lymphoblastic leukemia (T-ALL), but mutations have not been reported in BCP-ALL. We aimed to evaluate the clinical impact of WT1 mutations and single nucleotide polymorphisms (SNPs) in BCP-ALL. Pathogenic mutations in the WT1 gene were rarely seen in childhood BCP-ALL. However, five WT1 SNPs were identified. In survival analyses, WT1 SNP rs1799925 was found to be associated with worse OS, indicating that WT1 SNP rs1799925 may be a useful marker for clinical outcome in childhood BCP-ALL. We also explored whether WT1 mutations and SNPs in ccRCC could be used as biomarkers for risk and treatment stratification. We therefore examined whether SNPs or mutations in WT1 were associated with WT1 expression and clinical outcome. Sequencing analysis revealed that none of the previously reported WT1 mutations were found in ccRCC; however, we identified six different WT1 SNPs. Our data suggest that pathogenic WT1 mutations are not involved in ccRCC, and the prognostic significance of WT1 SNPs in ccRCC is considerably weak. However, a favorable OS and disease-specific survival were found in the few cases harboring the homozygous minor allele.OC has a poor prognosis, and early effective screening markers are lacking. Serous OCs are known to express the WT1 protein. Overexpressed oncogenic proteins can be considered potential candidate antigens for cancer vaccines and T-cell therapy. It was therefore of great interest to investigate whether anti-WT1 IgG antibody (Ab) measurements in plasma could serve as biomarkers of anti-OC response. We found limited prognostic impact, but the results indicated that anti-WT1 IgG Ab measurements in plasma and WT1 staining in tissue specimens could be potential biomarkers for patient outcome in the high-risk subtypes of OCs.In conclusion, the results of this thesis indicate that WT1 gene expression can provide information about MRD of patients with AML, and WT1 SNP rs1799925 may be used as a biomarker for predicting clinical outcome in childhood BCP-ALL. In ccRCC, the prognostic significance of WT1 SNPs is weak and limited to the subgroup of patients that are homozygous for the minor allele. In OCs anti-WT1 IgG Ab measurement in plasma and WT1 staining in tissue specimens could possibly be used as biomarkers for predicting patient outcome in the high-risk subtypes of OCs.
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| 4. |
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| 5. |
- Li, Xingru, 1987-
(författare)
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Wilms' tumor gene 1 in different types of cancer
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Wilms’ tumor gene 1 (WT1) was first reported as a tumor suppressor gene in Wilms’ tumor. However, later studies have shown the oncogenic properties of WT1 in a variety of tumors. It was recently proposed that WT1 was a chameleon gene, due to its dual functions in tumorigenesis. We aimed to investigate the clinical significance of WT1 as biomarker in acute myeloid leukemia (AML) and clear cell renal cell carcinoma (ccRCC) and to elucidate the function of WT1 as an oncogene in squamous cell carcinoma of head and neck (SCCHN).In AML, it was suggested that WT1 expression was an applicable marker of minimal residual disease (MRD). In adult patients with AML, we found a good correlation between WT1 expression levels normalized to two control genes, β-actin and ABL. Outcome could be predicted by a reduction in WT1 expression in bone marrow (≥ 1-log) detected less than 1 month after diagnosis, when β-actin was used as control. Also, irrespective of the control gene used, outcome could be predicted by a reduction in WT1 expression in peripheral blood (≥ 2-log) detected between 1 and 6 months after treatment initiation.Previous studies in RCC demonstrated that WT1 acted as a tumor suppressor. Thus, we tested whether single nucleotide polymorphisms (SNPs) or mutations in WT1 might be associated with WT1 expression and clinical outcome in patients with ccRCC. We performed sequencing analysis on 10 exons of the WT1 gene in a total of 182 patient samples, and we identified six different SNPs in the WT1 gene. We found that at least one or two copies of the minor allele were present in 61% of ccRCC tumor samples. However, no correlation was observed between WT1 SNP genotypes and RNA expression levels. Moreover, none of the previously reported WT1 mutations were found in ccRCC. Nevertheless, we found that a favorable outcome was associated the homozygous minor allele for WT1 SNP. We then further investigated whether WT1 methylation was related to WT1 expression and its clinical significance. Methylation array and pyrosequencing analyses showed that the WT1 promoter region CpG site, cg22975913, was the most frequently hypermethylated CpG site. We found a trend that showed nearly significant correlation between WT1 mRNA levels and hypermethylation in the 5’-untranslated region. Hypermethylation in the WT1 CpG site, cg22975913, was found to be associated with patient age and a worse prognosis.One previous study reported that WT1 was overexpressed in SCCHN. That finding suggested that WT1 might play a role in oncogenesis. We found that both WT1 and p63 could promote cell proliferation. A positive correlation between WT1 and p63 expression was observed, and we identified p63 as a WT1 target gene. Furthermore, several known WT1 and p63 target genes were affected by knocking down WT1. Also, co-immunoprecipitation analyses demonstrated a protein interaction between WT1 and p53.In summary, WT1 gene expression can provide useful information for MRD detection during treatment of patients with AML. In RCC, our results suggested that the prognostic impact of WT1 SNPs was limited to the subgroup of patients that were homozygous for the minor allele, and that WT1 promoter hypermethylation could be used as a prognostic biomarker. In SCCHN, WT1 and p63 acted as oncogenes by affecting multiple genes involved in cancer cell growth.
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| 6. |
- Li, Xingru, et al.
(författare)
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Wilms' tumor gene 1 regulates p63 and promotes cell proliferation in squamous cell carcinoma of the head and neck
- 2015
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Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Background: Wilms' tumor gene 1 (WT1) can act as a suppressor or activator of tumourigenesis in different types of human malignancies. The role of WT1 in squamous cell carcinoma of the head and neck (SCCHN) is not clear. Overexpression of WT1 has been reported in SCCHN, suggesting a possible oncogenic role for WT1. In the present study we aimed at investigating the function of WT1 and its previously identified protein partners p63 and p53 in the SCCHN cell line FaDu. Methods: Silencing RNA (siRNA) technology was applied to knockdown of WT1, p63 and p53 in FaDu cells. Cell proliferation was detected using MTT assay. Chromatin immunoprecipitation (ChIP)/PCR analysis was performed to confirm the effect of WT1 on the p63 promoter. Protein co-immunoprecipitation (co-IP) was used to find protein interaction between WT1 and p53/p63. Microarray analysis was used to identify changes of gene expression in response to knockdown of either WT1 or p63. WT1 RNA level was detected using real-time quantitative PCR (RT-qPCR) in patients with SCCHN. Results: We found that WT1 and p63 promoted cell proliferation, while mutant p53 (R248L) possessed the ability to suppress cell proliferation. We reported a novel positive correlation between WT1 and p63 expression. Subsequently, p63 was identified as a WT1 target gene. Furthermore, expression of 18 genes involved in cell proliferation, cell cycle regulation and DNA replication was significantly altered by downregulation of WT1 and p63 expression. Several known WT1 and p63 target genes were affected by WT1 knockdown. Protein interaction was demonstrated between WT1 and p53 but not between WT1 and p63. Additionally, high WT1 mRNA levels were detected in SCCHN patient samples. Conclusions: Our findings suggest that WT1 and p63 act as oncogenes in SCCHN, affecting multiple genes involved in cancer cell growth.
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| 7. |
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| 8. |
- Wu, Chen, et al.
(författare)
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WT1 Enhances Proliferation and Impedes Apoptosis in KRAS Mutant NSCLC via Targeting cMyc
- 2015
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Ingår i: Cellular Physiology and Biochemistry. - : S. Karger AG. - 1015-8987 .- 1421-9778. ; 35:2, s. 647-662
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Tidskriftsartikel (refereegranskat)abstract
- Background: A novel link between oncogenic KRAS signalling and WT1 was recently identified. We sought to investigate the role of WT1 and KRAS in proliferation and apoptosis. Methods: KRAS mutations and WT1 (cMyc) expression were detected using Sanger sequencing and real-time PCR in 77 patients with non-small cell lung cancer (NSCLC). Overexpression and knockdown of WT1 were generated with plasmid and siRNA via transient transfection technology in H1299 and H1568 cells. MTT assay for detection of cell proliferation, and TUNEL assay amd proteomic profiler assay for apoptosis evaluation were carried out. Dual luciferase reporter assay and ChIP-PCR were performed to validate the effect of WT1 on the cMyc promoter. Results: KRAS mutations showed a negative impact on overall survival ( OS). High expressions of WT1 and cMyc were associated with poor OS in KRAS mutant subgroup. The potential mechanisms that WT1 promotes proliferation and impedes apoptosis through affecting multiple apoptosis-related regulators in KRAS mutant NSCLC cells were identified. WT1 could activate cMyc promoter directly in KRAS mutant cells. Conclusion: The results suggest that WT1 and c-MYC expression is important for survival in KRAS mutant tumors as opposed to KRAS wild-type tumors. For treatment of KRAS mutant NSCLC, targeting WT1 and cMyc may provide alternative therapeutic strategies.
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| 9. |
- Armstrong, Scott A, et al.
(författare)
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FLT3 mutations in childhood acute lymphoblastic leukemia.
- 2004
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 103:9, s. 3544-3546
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Tidskriftsartikel (refereegranskat)abstract
- Activating mutations of the FLT3 receptor tyrosine kinase are common in acute myelogenous leukemia (AML) but are rare in adult acute lymphoblastic leukemia (ALL). We have recently shown that FLT3 is highly expressed and often mutated in ALLs with rearrangement of the mixed lineage leukemia (MLL) gene on chromosome 11q23. Because hyperdiploid ALL samples also show high-level expression of FLT3, we searched for the presence of FLT3 mutations in leukemic blasts from 71 patients with ALL. The data show that approximately 25% (6 of 25) of hyperdiploid ALL samples possess FLT3 mutations, whereas only 1 of 29 TEL/AML1-rearranged samples harbored mutations (P =.04, Fisher exact test). Three mutations are novel in-frame deletions within a 7-amino acid region of the receptor juxtamembrane domain. Finally, 3 samples from patients whose disease would relapse harbored FLT3 mutations. These data suggest that patients with hyperdiploid or relapsed ALL might be considered candidates for therapy with newly described small-molecule FLT3 inhibitors.
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| 10. |
- Li, Aihong, et al.
(författare)
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Automated white blood cell counts in cerebrospinal fluid using the body fluid mode on the platform Sysmex XE-5000
- 2014
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Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa Healthcare. - 0036-5513 .- 1502-7686. ; 74:8, s. 673-680
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The Sysmex XE-5000 offers automated quantification of red blood cells and white blood cells (WBCs) in body fluids, with differentiation of polymorphonuclear cells (PMNs) and mononuclear cells (MNCs). METHODS: We evaluated automated WBC counting in cerebrospinal fluid (CSF) using the body fluid mode on the Sysmex XE-5000, comparing it with flow cytometry as the reference method, and also with manual counting by microscopy. Experimental analysis for linearity and limit of detection was performed by diluting isolated WBCs in cell-free CSF. To study the ability to discriminate between PMNs and MNCs, samples were spiked using MNCs separated from peripheral blood. Comparison of WBC counts between a counting chamber and the XE-5000 was performed for 198 CSF samples. RESULTS: In the experimental set-up, within-run (CV 19%) and between-day imprecision (CV 15.3%) in quantitating total number of WBC on XE-5000 was acceptable for WBC counts >= 25x10(6)/L. Compared with expected cell counts, mean bias was +/- 2.6% for flow cytometry, +/- 5.5% for XE-5000 and -73.2% for manual counting. Differentiation between PMNs and MNCs was in concordance with flow cytometry. In comparisons of clinical CSF samples, overall agreement between the XE-5000 and manual counting was observed in 81% of the samples, but mean difference in WBC differentiation was higher for PMN (51.1x10(6)/L) than for MNC (7.95x10(6)/L). CONCLUSION: Despite limited precision at low WBC counts, XE-5000 could be a favourable alternative to the labour-intensive, time-consuming and less reliable manual counting and cuts turnaround times in routine CSF-based diagnosis.
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