| 1. |
- Gustafsson, Britt, et al.
(författare)
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KI, WU, and Merkel Cell Polyomavirus DNA was not Detected in Guthrie Cards of Children who Later Developed Acute Lymphoblastic Leukemia
- 2012
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Ingår i: Journal of pediatric hematology/oncology (Print). - 1077-4114 .- 1536-3678. ; 34:5, s. 364-367
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Tidskriftsartikel (refereegranskat)abstract
- Background: Neonatal dried blood spots (Guthrie cards) have been used to demonstrate a prenatal origin of clonal leukemia-specific genetic aberrations in several subgroups of childhood acute lymphoblastic leukemia (ALL). One hypothesis suggests that an infectious agent could initiate genetic transformation already in utero. In search for a possible viral agent, Guthrie cards were analyzed for the presence of 3 newly discovered polyomavirus Karolinska Institutet polymavirus (KIPyV), Washington University polyomavirus (WUPyV), and Merkel cell polyomavirus (MCPyV). Methods: Guthrie cards from 50 children who later developed ALL and 100 matched controls were collected and analyzed by standard or real-time polymerase chain reaction for the presence of the VP1 region of KIPyV, WUPyV, and MCPyV, and the LT region for MCPyV. Results and Conclusions: DNA from KIPyV, WUPyV, and MCPyV was not detected in neonatal blood samples from children with ALL or controls. Prenatal infections with these viruses are not likely to be etiological drivers for childhood leukemogenesis.
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| 2. |
- Gustafsson, Britt M., et al.
(författare)
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Origins of STIL-TAL1 fusion genes in children who later developed paediatric T-cell acute lymphoblastic leukaemia : An investigation of neonatal blood spots
- 2018
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Ingår i: Pediatric Blood & Cancer. - : WILEY. - 1545-5009 .- 1545-5017. ; 65:11
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Tidskriftsartikel (refereegranskat)abstract
- SCL/TAL1 interrupting locus (STIL)-T-cell acute leukaemia (TAL1) fusion genes are present in approximately 11-27% of children with paediatric T-cell acute lymphoblastic leukaemia (T-ALL), but the developmental timing of the rearrangement is still unknown. To investigate whether the fusion gene can be detected in neonatal blood spots (NBSs) from paediatric patients diagnosed with T-cell ALL, we analysed DNA from 38 paediatric patients with T-ALL by nested polymerase chain reaction and electrophoresis. The STIL-TAL1 fusion gene was not detected in NBSs from any of the 38 patients with T-ALL, suggesting that STIL-TAL1 fusion genes are most probably postnatal events in paediatric T-ALL.
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| 3. |
- Honkaniemi, Emma, et al.
(författare)
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Acquired aplastic anaemia in seven children with severe hepatitis with or without liver failure
- 2007
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 96:11, s. 1660-1664
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Aplastic anaemia following hepatitis may develop in as many as 1 of 3 patients with non-A, non-B and non-C hepatitis. Several causative factors have been discussed, such as viral infections and autoimmunity. Here we describe the natural history of this condition in 7 children and investigate possible hepatitis-causing agents. Methods: We reviewed the medical records, bone marrow and liver biopsies of 7 children with severe hepatitis, with or without liver failure, who subsequently had developed aplastic anaemia. Results: The median time from onset of hepatic symptoms until diagnosed onset of aplasia was 54 days. No associated viral infections could be identified. On liver biopsy, a majority had lobular inflammation but lacked signs of autoimmune hepatitis, findings compatible with a viral aetiology. Three of 6 children had low reticulocyte counts already at onset of hepatitis. All, but one patient is alive at median follow-up of 8 years. Conclusion: The unknown pathogenetic mechanism appears to target liver and bone marrow simultaneously, because half of the children concomitantly had low reticulocyte counts and severe liver failure.
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| 4. |
- Honkaniemi, Emma
(författare)
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Studies of specific viruses from Guthrie cards and prognostic markers in bone marrow samples from children diagnosed with leukemia
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aims: The aim of this thesis was to increase understanding of how molecular processes influence the development and risk assessment of childhood leukemia. Studies I and II investigates whether a specific virus infection in utero could be involved in a “first hit” in leukemogenesis. Studies III and IV examine whether alterations in protein expression from cell cycle regulating genes may predict a relapse in children with myeloid malignancies undergoing hematopoietic stem cell transplantation (HSCT). Background: Genetic alterations, analyzed at time of diagnosis in children who develop leukemia, have been traced back to neonatal dried blood spots (DBS). This suggests that the majority of chromosome translocations occur in utero during fetal hematopoiesis, generating a “first hit”. A “second hit” is then required to generate a leukemic clone. Today, experiments in vitro, animal models, and clinical observations have revealed that several viruses are oncogenic and capable of initiating a genetic alteration. Smith M postulated the theory that an in utero infection might be the “first hit”, causing genetic aberrations that could later lead to the development of the leukemic clone, which is supported by the early age of onset and space-time clustering data, based on time, place of birth, and diagnosis. Leukemia develops as a result of hematopoietic or lymphoid tissue with uncontrolled cell division. Normally cell division is controlled by the cell cycle, the network of which is complex with numerous regulating proteins both up and down stream, but also containing several feedback loops. The important regulators of this process are tumor suppressor genes, essential for normal cell proliferation and differentiation as well as for controlling DNA integrity. Errors in these genes or their protein expression affect the ability of the cell to check for DNA damage, thus tumors may occur. Proteins from these genes could serve as prognostic markers and predict relapse. Methods: In studies I and II we investigated neonatal DBS by PCR for the presence of adenovirus DNA (243 samples) and the three newly discovered polyomaviruses (50 samples) from children who later developed leukemia but also from controls (486 and 100 samples respectively). In studies III and IV we explored the expression of one (p53) respectively four (p53, p21, p16 and PTEN) cell cycle regulating proteins in bone marrow at diagnosis as well as pre and post HSCT in myeloid malignancies in children. We retrospectively collected clinical data and bone marrow samples from 33 children diagnosed with chronic myeloid malignancies (MDS, JMML and CML), 34 children diagnosed with AML as well as 55 controls. The samples were prepared by tissue micro array (TMA) as well as immunohistochemistry and examined for protein expression in a light microscope. Results: In study I we detected adenovirus DNA in only two patients who later developed leukemia, but in none of the controls. In study II all the samples were negative for KIPyV, WUPyV and MCPyV DNA in both patients and controls. In study III we found an overexpression of p53 protein at diagnosis that significantly predicted relapse after HSCT in children with rare chronic myeloid malignancies. In study IV a significantly higher p53 expression was found in the relapse compared to the non-relapse group at six months post HSCT in children with AML, suggesting that p53 may be used as prognostic markers for predicting a relapse. In addition, the calculated cut off level for p53 at diagnosis (study III) and at six months (study IV) post HSCT was approximately 20%, which indicates that a p53 expression over 20% may predict relapse in children with myeloid malignancies. Conclusion: Although we did not find an association between adenoviruses or the three newly discovered polyomaviruses and the development of childhood leukemia, a virus could still be involved in this process; the virus may have escaped detection, other new viruses could be involved or a virus could precipitate the “second hit”. We suggest that evaluation of p53 protein expression may be used as a supplement to regular prognostic markers both pre and post HSCT. To further evaluate this, a prospective multicenter study has been started.
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