| 1. |
- Afshari, Maryam K., et al.
(författare)
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Activation of PLAG1 and HMGA2 by gene fusions involving the transcriptional regulator gene NFIB
- 2020
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Ingår i: Genes Chromosomes & Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 59:11, s. 652-660
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Tidskriftsartikel (refereegranskat)abstract
- The pleomorphic adenoma (PA), which is the most common salivary gland neoplasm, is a benign tumor characterized by recurrent chromosome rearrangements involving 8q12 and 12q14-15. We have previously shown that thePLAG1andHMGA2oncogenes are the targets of these rearrangements. Here, we have identified previously unrecognized subsets of PAs with ins(9;8)/t(8;9) (n = 5) and ins(9;12)/t(9;12) (n = 8) and breakpoints located in the vicinity of thePLAG1andHMGA2loci. RNA-sequencing and reverse transcriptase (RT)-PCR analyses of a case with an ins(9;8) revealed a novelNFIB-PLAG1fusion in whichNFIBexon 4 is linked toPLAG1exon 3. In contrast to the developmentally regulatedPLAG1gene,NFIBwas highly expressed in normal salivary gland, indicating thatPLAG1in this case, as in other variant fusions, is activated by promoter swapping. RT-PCR analysis of three PAs with t(9;12) revealed two tumors with chimeric transcripts consisting ofHMGA2exon 4 linked toNFIBexons 9 or 3 and one case with a fusion linkingHMGA2exon 3 toNFIBexon 9. TheNFIBfusion events resulted in potent activation ofPLAG1andHMGA2. Analysis of the chromatin landscape surroundingNFIBrevealed several super-enhancers in the 5 '- and 3 '-parts of theNFIBlocus and its flanking sequences. These findings indicate thatPLAG1andHMGA2, similar toMYBin adenoid cystic carcinoma, may be activated by enhancer-hijacking events, in which super-enhancers inNFIBare translocated upstream ofPLAG1or downstream ofHMGA2. Our results further emphasize the role ofNFIBas a fusion partner to multiple oncogenes in histopathologically different types of salivary gland tumors.
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| 2. |
- Andersson, Natalie, et al.
(författare)
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Inactivation of RB1, CDKN2A and TP53 have distinct effects on genomic stability at side-by-side comparison in karyotypically normal cells
- 2023
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Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 62:2, s. 93-100
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Tidskriftsartikel (refereegranskat)abstract
- Chromosomal instability is a common feature in malignant tumors. Previous studies have indicated that inactivation of the classical tumor suppressor genes RB1, CDKN2A and TP53 may contribute to chromosomal aberrations in cancer by disrupting different aspects of the cell cycle and DNA damage checkpoint machinery. We performed a side-by-side comparison of how inactivation of each of these genes affected chromosomal stability in vitro. Using CRISPR-Cas9 technology, RB1, CDKN2A and TP53 were independently knocked out in karyotypically normal immortalized cells, after which these cells were followed over time. Bulk RNA sequencing revealed a distinct phenotype with upregulation of pathways related to cell cycle control and proliferation in all three knockouts. Surprisingly, the RB1 and CDKN2A knocked out cell lines did not harbor more copy number aberrations than wild-type cells, despite culturing for months. The TP53-knocked out cells, in contrast, showed a massive amount of copy number alterations and saltatory evolution through whole genome duplication. This side-by-side comparison indicated that the effects on chromosomal stability from inactivation of RB1 and CDKN2A are negligible compared to inactivation of TP53, under the same conditions in a non-stressful environment, even though partly overlapping regulatory pathways are affected.
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| 3. |
- Arbajian, Elsa, et al.
(författare)
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Deep sequencing of myxoinflammatory fibroblastic sarcoma
- 2020
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Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 59:5, s. 309-317
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Tidskriftsartikel (refereegranskat)abstract
- Myxoinflammatory fibroblastic sarcoma (MIFS) has recurrent genetic features in the form of a translocation t(1;10)(p22-31;q24-25), BRAF gene fusions, and/or an amplicon in 3p11-12 including the VGLL3 gene. The breakpoints on chromosomes 1 and 10 in the t(1;10) cluster in or near the TGFBR3 and OGA genes, respectively. We here used a combination of deep sequencing of the genome (WGS), captured sequences (Cap-seq), and transcriptome (RNA-seq) and genomic arrays to investigate the molecular outcome of the t(1;10) and the VGLL3 amplicon, as well as to assess the spectrum of other recurrent genomic features in MIFS. Apart from a ROBO1-BRAF chimera in a t(1;10)-negative MIFS-like tumor, no fusion gene was found at RNA-seq. This was in line with WGS and Cap-seq results, revealing variable breakpoints in chromosomes 1 and 10 and genomic breakpoints that should not yield functional fusion transcripts. The most common genomic rearrangements were breakpoints in or around the OGA, NPM3, and FGF8 genes in chromosome band 10q24, and loss of 1p11-p21 and 10q26-qter (all simultaneously present in 6/7 MIFS); a breakpoint in or near TGFBR3 in chromosome 1 was found in four of these tumors. Amplification and overexpression of VGLL3 was a consistent feature in MIFS and MIFS-like tumors with amplicons in 3p11-12. The significant molecular genetic outcome of the recurrent t(1;10) could be loss of genetic material from 1p and 10q. Other recurrent genomic imbalances in MIFS, such as homozygous loss of CDKN2A and 3p- and 13q-deletions, are shared with other sarcomas, suggesting overlapping pathogenetic pathways. This article is protected by copyright. All rights reserved.
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| 4. |
- Biloglav, Andrea, et al.
(författare)
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SFPQ-ABL1-positive B-cell precursor acute lymphoblastic leukemias
- 2020
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Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257 .- 1098-2264.
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, a subgroup of B‐cell precursor acute lymphoblastic leukemia (BCP ALL) without an established abnormality (“B‐other”) has been shown to be characterized by rearrangements of ABL1 , ABL2 , CSF1R , or PDGFRB (a.k.a. ABL‐class genes). Using FISH with probes for these genes, we screened 55 pediatric and 50 adult B‐other cases. Three (6%) of the adult but none of the childhood B‐other cases were positive for ABL‐class aberrations. RT‐PCR and sequencing confirmed a rare SFPQ‐ABL1 fusion in one adult B‐other case with t(1;9)(p34;q34). Only six SFPQ ‐ABL1 ‐positive BCP ALLs have been reported, present case included. A review of these shows that all harbored fusions between exon 9 of SFPQ and exon 4 of ABL1 , that the fusion is typically found in adolescents/younger adults without hyperleukocytosis, and that IKZF1 deletions are recurrent. The few patients not treated with tyrosine kinase inhibitors (TKIs) and/or allogeneic stem cell transplantation relapsed, strengthening the notion that TKI should be added to the therapy of SFPQ ‐ABL1 ‐positive BCP ALL.
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| 5. |
- Cabrerizo Granados, David, et al.
(författare)
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The clinical phenotype of germline RUNX1 mutations in relation to the accompanying somatic variants and RUNX1 isoform expression
- 2023
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Ingår i: Genes, Chromosomes and Cancer. - : John Wiley & Sons. - 1045-2257 .- 1098-2264. ; 62:11, s. 672-677
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Tidskriftsartikel (refereegranskat)abstract
- Germline RUNX1 mutations lead to familial platelet disorder with associated myeloid malignancy (FPDMM), characterized by thrombocytopenia, abnormal bleeding, and an elevated risk of developing myelodysplastic neoplasia (MDS) and acute myeloid leukemia (AML) at young age. However, it is not known why or how germline carriers of RUNX1 mutations have a particular propensity to develop myeloid hematologic malignancies, but the acquisition and composition of somatic mutations are believed to initiate and determine disease progression. We present a novel family pedigree that shares a common germline RUNX1R204* variant and exhibits a spectrum of somatic mutations and related myeloid malignancies (MM). RUNX1 mutations are associated with inferior clinical outcome; however, the proband of this family developed MDS with ring sideroblasts (MDS-RS), classified as a low-risk MDS subgroup. His relatively indolent clinical course is likely due to a specific somatic mutation in the SF3B1 gene. While the three main RUNX1 isoforms have been ascribed various roles in normal hematopoiesis, they are now being increasingly recognized as involved in myeloid disease. We investigated the RUNX1 transcript isoform patterns in the proband and his sister, who carries the same germline RUNX1R204* variant, and has FPDMM but no MM. We demonstrate a RUNX1a increase in MDS-RS, as previously reported in MM. Interestingly, we identify a striking unbalance of RUNX1b and -c in FPDMM. In conclusion, this report reinforces the relevance of somatic variants on the clinical phenotypic heterogeneity in families with germline RUNX1 deficiency and investigates a potential new role for RUNX1 isoform disequilibrium as a mechanism for development of MM.
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| 6. |
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| 7. |
- Fehr, Andre, et al.
(författare)
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Increased MYB alternative promoter usage is associated with relapse in acute lymphoblastic leukemia
- 2023
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Ingår i: Genes Chromosomes & Cancer. - : John Wiley & Sons. - 1045-2257 .- 1098-2264. ; 62:10, s. 597-606
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Tidskriftsartikel (refereegranskat)abstract
- Therapy-resistant disease is a major cause of death in patients with acute lympho-blastic leukemia (ALL). Activation of the MYB oncogene is associated with ALL and leads to uncontrolled neoplastic cell proliferation and blocked differentiation. Here, we used RNA-seq to study the clinical significance of MYB expression and MYB alter-native promoter (TSS2) usage in 133 pediatric ALLs. RNA-seq revealed that all cases analyzed overexpressed MYB and demonstrated MYB TSS2 activity. qPCR analyses confirmed the expression of the alternative MYB promoter also in seven ALL cell lines. Notably, high MYB TSS2 activity was significantly associated with relapse (p = 0.007). Moreover, cases with high MYB TSS2 usage showed evidence of therapy-resistant disease with increased expression of ABC multidrug resistance transporter genes (e.g., ABCA2, ABCB5, and ABCC10) and enzymes catalyzing drug degradation (e.g., CYP1A2, CYP2C9, and CYP3A5). Elevated MYB TSS2 activity was further associated with augmented KRAS signaling (p < 0.05) and decreased methyla-tion of the conventional MYB promoter (p < 0.01). Taken together, our results sug-gest that MYB alternative promoter usage is a novel potential prognostic biomarker for relapse and therapy resistance in pediatric ALL.
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| 8. |
- Haglund, Cecilia, et al.
(författare)
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An intraosseous myoepithelial carcinoma with a EWSR1::PBX3 fusion
- 2023
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Ingår i: Genes, Chromosomes and Cancer. - : WILEY. - 1045-2257 .- 1098-2264. ; 62:10, s. 607-610
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Tidskriftsartikel (refereegranskat)abstract
- Herein we report a case of an intraosseous myoepithelial carcinoma harboring a EWSR1::PBX3 fusion gene. The patient was a 64-year-old male found to have a 7 cm destructive lesion in the distal ulna with an extraosseous soft tissue component. Microscopic examination of the resected tumor showed a spindle-cell lesion within a sclerotic stroma and intravascular tumor emboli. At higher power the tumor cells showed moderate nuclear atypia with a high mitotic count (20 per mm(2)). Immunohistochemistry revealed diffuse EMA positivity and focal pancytokeratin (AE1/AE3) and S100 expression, consistent with myoepithelial differentiation. NGS using the Oncomine Childhood Cancer Assay (Thermo Fisher Scientific, Inc.) revealed a EWSR1-PBX3 fusion and ABL amplification. The patient subsequently developed local recurrence as well as distant lymph node, lung and vertebral metastases; he is currently awaiting systemic treatment in the context of a clinical trial. In this report, we present a rare case of a skeletal myoepithelial tumor harboring a EWSR1::PBX3 fusion with demonstrated histological and clinical features of malignancy.
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| 9. |
- Ibstedt, Sebastian, et al.
(författare)
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A cryptic EWSR1::DDIT3 fusion in myxoid liposarcoma: Potential pitfalls with FISH and cytogenetics
- 2023
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Ingår i: Genes Chromosomes and Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 62:3, s. 167-170
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Tidskriftsartikel (refereegranskat)abstract
- Myxoid liposarcoma (MLS) is molecularly characterized by fusions involving the DDIT3 gene in chromosome band 12q13; the fusion partner is FUS in band 16p11 in 90–95% of the cases and EWSR1 in band 22q12 in the remaining 5–10%. Hence, molecular studies, often fluorescence in situ hybridization (FISH) for DDIT3 rearrangement, are useful for establishing a correct diagnosis. Although all MLS tumors should have DDIT3 fusions, it is important to be aware of reasons for potential false-negative results. We here present a case of MLS that was negative for FISH for DDIT3, that showed an unexpected t(11;22) at G-banding, but that displayed a characteristic EWSR1::DDIT3 fusion at RNA-sequencing. The results suggest that neoplasia-associated fusions that, due to the transcriptional orientations of the two genes involved, cannot arise through only two double-strand breaks are more likely to be associated with negative FISH-findings and unexpected karyotypes.
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| 10. |
- Javanmardi, Niloufar, et al.
(författare)
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Analysis of ALK, MYCN, and the ALK ligand ALKAL2 (FAM150B/AUG alpha) in neuroblastoma patient samples with chromosome arm 2p rearrangements
- 2020
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Ingår i: Genes Chromosomes & Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 59:1, s. 50-57
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Tidskriftsartikel (refereegranskat)abstract
- Gain of chromosome arm 2p is a previously described entity in neuroblastoma (NB). This genomic address is home to two important oncogenes in NB-MYCN and anaplastic lymphoma kinase (ALK). MYCN amplification is a critical prognostic factor coupled with poor prognosis in NB. Mutation of the ALK receptor tyrosine kinase has been described in both somatic and familial NB. Here, ALK activation occurs in the context of the full-length receptor, exemplified by activating point mutations in NB. ALK overexpression and activation, in the absence of genetic mutation has also been described in NB. In addition, the recently identified ALK ligand ALKAL2 (previously described as FAM150B and AUG alpha) is also found on the distal portion of 2p, at 2p25. Here we analyze 356 NB tumor samples and discuss observations indicating that gain of 2p has implications for the development of NB. Finally, we put forward the hypothesis that the effect of 2p gain may result from a combination of MYCN, ALK, and the ALK ligand ALKAL2.
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