| 1. |
- Abrahamsson, Jonas, 1954, et al.
(författare)
-
Improved outcome after relapse in children with acute myeloid leukaemia.
- 2007
-
Ingår i: British journal of haematology. - : Wiley. - 0007-1048 .- 1365-2141. ; 136:2, s. 229-236
-
Tidskriftsartikel (refereegranskat)abstract
- In the Nordic Society for Paediatric Haematology and Oncology paediatric study acute myeloid leukaemia (AML) 93, event-free survival was 50% and overall survival was 66%, indicating that many patients were cured following relapse. Factors influencing outcome in children with relapsed AML were investigated. The study included all 146 children in the Nordic countries diagnosed with AML between 1988 and 2003, who relapsed. Data on disease characteristics and relapse treatment were related to outcome. Sixty-six percentage achieved remission with survival after relapse (5 years) 34 +/- 4%. Of 122 patients who received re-induction therapy, 77% entered remission with 40 +/- 5% survival. Remission rates were similar for different re-induction regimens but fludarabine, cytarabine, granulocyte colony-stimulating factor-based therapy had low treatment-related mortality. Prognostic factors for survival were duration of first complete remission (CR1) and stem cell transplantation (SCT) in CR1. In early relapse (<1 year in CR1), survival was 21 +/- 5% compared with 48 +/- 6% in late relapse. For children receiving re-induction therapy, survival in early relapse was 29 +/- 6% and 51 +/- 6% in late. Patients treated in CR1 with SCT, autologous SCT or chemotherapy had a survival of 18 +/- 9, 5 +/- 5 and 41 +/- 5%, respectively. Survival was 62 +/- 6% in 64 children given SCT as part of their relapse therapy. A significant proportion of children with relapsed AML can be cured, even those with early relapse. Children who receive re-induction therapy, enter remission and proceed to SCT can achieve a cure rate of 60%.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Andersson, Anna, et al.
(författare)
-
Gene expression profiling of leukemic cell lines reveals conserved molecular signatures among subtypes with specific genetic aberrations
- 2005
-
Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 19:6, s. 1042-1050
-
Tidskriftsartikel (refereegranskat)abstract
- Hematologic malignancies are characterized by fusion genes of biological/clinical importance. Immortalized cell lines with such aberrations are today widely used to model different aspects of leukemogenesis. Using cDNA microarrays, we determined the gene expression profiles of 40 cell lines as well as of primary leukemias harboring 11q23/MLL rearrangements, t(1;19)[TCF3/PBX1], t(12;21)[ETV6/RUNX1], t(8;21)[RUNX1/CBFA2T1], t(8;14) [IGH@/MYC], t(8;14)[TRA@/MYC], t(9;22)[BCR/ABL1], t(10;11) [PICALM/MLLT10], t(15;17)[PML/RARA], or inv(16)[CBFB/MYH11]. Unsupervised classification revealed that hematopoietic cell lines of diverse origin, but with the same primary genetic changes, segregated together, suggesting that pathogenetically important regulatory networks remain conserved despite numerous passages. Moreover, primary leukemias cosegregated with cell lines carrying identical genetic rearrangements, further supporting that critical regulatory pathways remain intact in hematopoietic cell lines. Transcriptional signatures correlating with clinical subtypes/primary genetic changes were identified and annotated based on their biological/molecular properties and chromosomal localization. Furthermore, the expression profile of tyrosine kinase-encoding genes was investigated, identifying several differentially expressed members, segregating with primary genetic changes, which may be targeted with tyrosine kinase inhibitors. The identified conserved signatures are likely to reflect regulatory networks of importance for the transforming abilities of the primary genetic changes and offer important pathogenetic insights as well as a number of targets for future rational drug design.
|
|
| 5. |
- Andersson, Anna, et al.
(författare)
-
Microarray-based classification of a consecutive series of 121 childhood acute leukemias: prediction of leukemic and genetic subtype as well as of minimal residual disease status.
- 2007
-
Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 21:6, s. 1198-1203
-
Tidskriftsartikel (refereegranskat)abstract
- Gene expression analyses were performed on 121 consecutive childhood leukemias (87 B-lineage acute lymphoblastic leukemias (ALLs), 11 T-cell ALLs and 23 acute myeloid leukemias (AMLs)), investigated during an 8-year period at a single center. The supervised learning algorithm k-nearest neighbor was utilized to build gene expression predictors that could classify the ALLs/AMLs according to clinically important subtypes with high accuracy. Validation experiments in an independent data set verified the high prediction accuracies of our classifiers. B-lineage ALLs with uncharacteristic cytogenetic aberrations or with a normal karyotype displayed heterogeneous gene expression profiles, resulting in low prediction accuracies. Minimal residual disease status (MRD) in T-cell ALLs with a high (40.1%) MRD at day 29 could be classified with 100% accuracy already at the time of diagnosis. In pediatric leukemias with uncharacteristic cytogenetic aberrations or with a normal karyotype, unsupervised analysis identified two novel subgroups: one consisting mainly of cases remaining in complete remission (CR) and one containing a few patients in CR and all but one of the patients who relapsed. This study of a consecutive series of childhood leukemias confirms and extends further previous reports demonstrating that global gene expression profiling provides a valuable tool for genetic and clinical classification of childhood leukemias.
|
|
| 6. |
- Andersson, Anna, et al.
(författare)
-
The landscape of somatic mutations in infant MLL-rearranged acute lymphoblastic leukemias.
- 2015
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:4, s. 192-330
-
Tidskriftsartikel (refereegranskat)abstract
- Infant acute lymphoblastic leukemia (ALL) with MLL rearrangements (MLL-R) represents a distinct leukemia with a poor prognosis. To define its mutational landscape, we performed whole-genome, exome, RNA and targeted DNA sequencing on 65 infants (47 MLL-R and 18 non-MLL-R cases) and 20 older children (MLL-R cases) with leukemia. Our data show that infant MLL-R ALL has one of the lowest frequencies of somatic mutations of any sequenced cancer, with the predominant leukemic clone carrying a mean of 1.3 non-silent mutations. Despite this paucity of mutations, we detected activating mutations in kinase-PI3K-RAS signaling pathway components in 47% of cases. Surprisingly, these mutations were often subclonal and were frequently lost at relapse. In contrast to infant cases, MLL-R leukemia in older children had more somatic mutations (mean of 6.5 mutations/case versus 1.3 mutations/case, P = 7.15 × 10(-5)) and had frequent mutations (45%) in epigenetic regulators, a category of genes that, with the exception of MLL, was rarely mutated in infant MLL-R ALL.
|
|
| 7. |
- Andreasson, Patrik, et al.
(författare)
-
Cytogenetic and FISH studies of a single center consecutive series of 152 childhood acute lymphoblastic leukemias
- 2000
-
Ingår i: European Journal of Haematology. - : Wiley. - 1600-0609 .- 0902-4441. ; 65:1, s. 40-51
-
Tidskriftsartikel (refereegranskat)abstract
- Between 1977 and 1996, cytogenetic investigations were performed on 182 childhood (< or = 16 yr) acute lymphoblastic leukemias (ALL), constituting 94% (182 of 194) of all ALL patients diagnosed and treated at the Departments of Pediatrics, Lund and Malmo University Hospitals, Sweden, during these two decades. The cytogenetic analyses were successful in 152 cases (84%). The failure rate was higher for the ALL investigated before 1987 (30% vs. 4%, p < 0.0001), and also the incidence of cytogenetically normal cases was higher during 1977-86 (43% vs. 25%, p < 0.05). Clonal chromosomal abnormalities were found in 103 (68%) ALL. Structural rearrangements were detected, by chromosome banding alone, in 76 cases (50%). Fluorescence in situ hybridization (FISH) was used to identify cases with t(12;21), 11q23 rearrangements, and 9p deletions, using probes for ETV6/CBFA2, MLL, and CDKN2A/B, in 72 cases from which cells in fixative and/or unstained metaphase preparations were available. In total, the most common structural rearrangements were del(9p) (17%), t(12;21) (15%), del(6q) (8%), and MLL rearrangements (4%). Six (32%) of nineteen cytogenetically normal ALL analyzed by FISH harbored cryptic abnormalities; three displayed t(12;21) and four had del(9p), one of which also carried a t(12;21). Five (45%) of the t(12;21)-positive ALL showed +der(21)t(12;21) or ider(21)(q10)t(12;21), resulting in the formation of double fusion genes. Among the more rare aberrations, eight structural rearrangements were identified as novel recurrent ALL-associated abnormalities, and nine cases harbored rearrangements previously not reported. Sixteen cases displayed karyotypically unrelated clones at different investigations. Seven ALL (5%) showed simple chromosomal changes, unrelated to the aberrations detected at diagnosis, during morphologic and clinical remission, and in all but one instance the patients remained in remission, with the abnormal clone disappearing in subsequent investigations. This indicates that the emergence of novel clonal chromosomal aberrations during remission in childhood ALL is rather common and does not by necessity predict a forthcoming relapse.
|
|
| 8. |
- Borssen, Magnus, et al.
(författare)
-
Promoter DNA methylation pattern identifies prognostic subgroups in childhood T-cell acute lymphoblastic leukemia.
- 2013
-
Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 8:6
-
Tidskriftsartikel (refereegranskat)abstract
- Treatment of pediatric T-cell acute lymphoblastic leukemia (T-ALL) has improved, but there is a considerable fraction of patients experiencing a poor outcome. There is a need for better prognostic markers and aberrant DNA methylation is a candidate in other malignancies, but its potential prognostic significance in T-ALL is hitherto undecided.
|
|
| 9. |
|
|
| 10. |
- Davidsson, Josef, et al.
(författare)
-
The DNA methylome of pediatric acute lymphoblastic leukemia
- 2009
-
Ingår i: HUMAN MOLECULAR GENETICS. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 18:21, s. 4054-4065
-
Tidskriftsartikel (refereegranskat)abstract
- Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy, with high hyperdiploidy [51-67 chromosomes] and the t(12;21)(p13;q22) [ETV6/RUNX1 fusion] representing the most frequent abnormalities. Although these arise in utero, there is long latency before overt ALL, showing that additional changes are needed. Gene dysregulation through hypermethylation may be such an event; however, this has not previously been investigated in a detailed fashion. We performed genome-wide methylation profiling using bacterial artificial chromosome arrays and promoter-specific analyses of high hyperdiploid and ETV6/RUNX1-positive ALLs. In addition, global gene expression analyses were performed to identify associated expression patterns. Unsupervised cluster and principal component analyses of the chromosome-wide methylome profiles could successfully subgroup the two genetic ALL types. Analysis of all currently known promoter-specific CpG islands demonstrated that several B-cell- and neoplasia-associated genes were hypermethylated and underexpressed, indicating that aberrant methylation plays a significant leukemogenic role. Interestingly, methylation hotspots were associated with chromosome bands predicted to harbor imprinted genes and the tri-/tetrasomic chromosomes in the high hyperdiploid ALLs were less methylated than their disomic counterparts. Decreased methylation of gained chromosomes is a previously unknown phenomenon that may have ramifications not only for the pathogenesis of high hyperdiploid ALL but also for other disorders with acquired or constitutional numerical chromosome anomalies.
|
|
