| 1. |
- Giagounidis, Aristoteles, et al.
(författare)
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Outcomes in RBC transfusion-dependent patients with Low-/Intermediate-1-risk myelodysplastic syndromes with isolated deletion 5q treated with lenalidomide: a subset analysis from the MDS-004 study
- 2014
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Ingår i: European Journal of Haematology. - : Wiley. - 1600-0609 .- 0902-4441. ; 93:5, s. 429-438
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Tidskriftsartikel (refereegranskat)abstract
- ObjectiveA subset analysis of the randomised, phase 3, MDS-004 study to evaluate outcomes in patients with International Prognostic Scoring System (IPSS)-defined Low-/Intermediate (Int)-1-risk myelodysplastic syndromes (MDS) with isolated del(5q). MethodsPatients received lenalidomide 10mg/d (days 1-21; n=47) or 5mg/d (days 1-28; n=43) on 28-d cycles or placebo (n=45). From the placebo and lenalidomide 5mg groups, 84% and 58% of patients, respectively, crossed over to lenalidomide 5 or 10mg at 16wk, respectively. ResultsRates of red blood cell-transfusion independence (RBC-TI) 182d were higher in the lenalidomide 10mg (57.4%; P<0.0001) and 5mg (37.2%; P=0.0001) groups vs. placebo (2.2%). Cytogenetic response rates (major+minor responses) were 56.8% (P<0.0001), 23.1% (P=0.0299) and 0%, respectively. Two-year cumulative risk of acute myeloid leukaemia progression was 12.6%, 17.4% and 16.7% in the lenalidomide 10mg, 5mg, and placebo groups, respectively. In a 6-month landmark analysis, overall survival was longer in lenalidomide-treated patients with RBC-TI 182d vs. non-responders (P=0.0072). The most common grade 3-4 adverse event was myelosuppression. ConclusionsThese data support the clinical benefits and acceptable safety profile of lenalidomide in transfusion-dependent patients with IPSS-defined Low-/Int-1-risk MDS with isolated del(5q).
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| 2. |
- Reimer, Jana, et al.
(författare)
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CRISPR-Cas9-induced t(11;19)/MLL-ENL translocations initiate leukemia in human hematopoietic progenitor cells in vivo
- 2017
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Ingår i: Haematologica. - : Ferrata Storti Foundation (Haematologica). - 0390-6078 .- 1592-8721. ; 102:9, s. 1558-1566
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Tidskriftsartikel (refereegranskat)abstract
- Chromosomal translocations that generate oncogenic fusion proteins are causative for most pediatric leukemias and frequently affect the MLL/ KMT2A gene. In vivo modeling of bona fide chromosomal translocations in human hematopoietic stem and progenitor cells is challenging but essential to determine their actual leukemogenic potential. We therefore developed an advanced lentiviral CRISPR-Cas9 vector that efficiently transduced human CD34(+) hematopoietic stem and progenitor cells and induced the t(11; 19)/MLL-ENL translocation. Leveraging this system, we could demonstrate that hematopoietic stem and progenitor cells harboring the translocation showed only a transient clonal growth advantage in vitro. In contrast, t(11; 19)/MLL-ENL-harboring CD34(+) hematopoietic stem and progenitor cells not only showed longterm engraftment in primary immunodeficient recipients, but t(11; 19)/ MLL-ENL also served as a first hit to initiate a monocytic leukemia-like disease. Interestingly, secondary recipients developed acute lymphoblastic leukemia with incomplete penetrance. These findings indicate that environmental cues not only contribute to the disease phenotype, but also to t(11; 19)/ MLL-ENL-mediated oncogenic transformation itself. Thus, by investigating the true chromosomal t(11; 19) rearrangement in its natural genomic context, our study emphasizes the importance of environmental cues for the pathogenesis of pediatric leukemias, opening an avenue for novel treatment options.
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| 3. |
- Tehranchi, Ramin, et al.
(författare)
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Persistent malignant stem cells in del(5q) myelodysplasia in remission.
- 2010
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Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 363:11, s. 1025-1037
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The in vivo clinical significance of malignant stem cells remains unclear. METHODS: Patients who have the 5q deletion (del[5q]) myelodysplastic syndrome (interstitial deletions involving the long arm of chromosome 5) have complete clinical and cytogenetic remissions in response to lenalidomide treatment, but they often have relapse. To determine whether the persistence of rare but distinct malignant stem cells accounts for such relapses, we examined bone marrow specimens obtained from seven patients with the del(5q) myelodysplastic syndrome who became transfusion-independent while receiving lenalidomide treatment and entered cytogenetic remission. RESULTS: Virtually all CD34+, CD38+ progenitor cells and stem cells that were positive for CD34 and CD90, with undetectable or low CD38 (CD38−/low), had the 5q deletion before treatment. Although lenalidomide efficiently reduced these progenitors in patients in complete remission, a larger fraction of the minor, quiescent, CD34+,CD38-/low, CD90+ del(5q) stem cells as well as functionally defined del(5q) stem cells remained distinctly resistant to lenalidomide. Over time, lenalidomide resistance developed in most of the patients in partial and complete remission, with recurrence or expansion of the del(5q) clone and clinical and cytogenetic progression. CONCLUSIONS: In these patients with the del(5q) myelodysplastic syndrome, we identified rare and phenotypically distinct del(5q) myelodysplastic syndrome stem cells that were also selectively resistant to therapeutic targeting at the time of complete clinical and cytogenetic remission. (Funded by the EuroCancerStemCell Consortium and others.)
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| 4. |
- Woll, Petter S, et al.
(författare)
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Myelodysplastic Syndromes Are Propagated by Rare and Distinct Human Cancer Stem Cells In Vivo.
- 2014
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Ingår i: Cancer Cell. - : Elsevier BV. - 1878-3686 .- 1535-6108. ; 25:6, s. 794-808
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Tidskriftsartikel (refereegranskat)abstract
- Evidence for distinct human cancer stem cells (CSCs) remains contentious and the degree to which different cancer cells contribute to propagating malignancies in patients remains unexplored. In low- to intermediate-risk myelodysplastic syndromes (MDS), we establish the existence of rare multipotent MDS stem cells (MDS-SCs), and their hierarchical relationship to lineage-restricted MDS progenitors. All identified somatically acquired genetic lesions were backtracked to distinct MDS-SCs, establishing their distinct MDS-propagating function in vivo. In isolated del(5q)-MDS, acquisition of del(5q) preceded diverse recurrent driver mutations. Sequential analysis in del(5q)-MDS revealed genetic evolution in MDS-SCs and MDS-progenitors prior to leukemic transformation. These findings provide definitive evidence for rare human MDS-SCs in vivo, with extensive implications for the targeting of the cells required and sufficient for MDS-propagation.
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