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- Arbajian, Elsa, et al.
(författare)
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Recurrent EWSR1-CREB3L1 Gene Fusions in Sclerosing Epithelioid Fibrosarcoma.
- 2014
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Ingår i: American Journal of Surgical Pathology. - 1532-0979. ; 38:6, s. 801-808
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Tidskriftsartikel (refereegranskat)abstract
- Sclerosing epithelioid fibrosarcoma (SEF) and low-grade fibromyxoid sarcoma (LGFMS) are 2 distinct types of sarcoma, with a subset of cases showing overlapping morphologic and immunohistochemical features. LGFMS is characterized by expression of the MUC4 protein, and about 90% of cases display a distinctive FUS-CREB3L2 gene fusion. In addition, SEF is often MUC4 positive, but is genetically less well studied. Fluorescence in situ hybridization (FISH) studies have shown involvement of the FUS gene in the majority of so-called hybrid LGFMS/SEF and in 10% to 25% of sarcomas with pure SEF morphology. In this study, we investigated a series of 10 primary tumors showing pure SEF morphology, 4 cases of LGFMS that at local or distant relapse showed predominant SEF morphology, and 1 primary hybrid LGFMS/SEF. All but 1 case showed diffuse expression for MUC4. Using FISH, reverse transcription polymerase chain reaction, and/or mRNA sequencing in selected cases, we found recurrent EWSR1-CREB3L1 fusion transcripts by reverse transcription polymerase chain reaction in 3/10 pure SEF cases and splits and deletions of the EWSR1 and/or CREB3L1 genes by FISH in 6 additional cases. All 5 cases of LGFMS with progression to SEF morphology or hybrid features had FUS-CREB3L2 fusion transcripts. Our results indicate that EWSR1 and CREB3L1 rearrangements are predominant over FUS and CREB3L2 rearrangements in pure SEF, highlighting that SEF and LGFMS are different tumor types, with different impacts on patient outcome.
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2. |
- Ehnman, Monika, et al.
(författare)
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Distinct Effects of Ligand-Induced PDGFR alpha and PDGFR beta Signaling in the Human Rhabdomyosarcoma Tumor Cell and Stroma Cell Compartments
- 2013
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Ingår i: Cancer Research. - 1538-7445. ; 73:7, s. 2139-2149
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Tidskriftsartikel (refereegranskat)abstract
- Platelet-derived growth factor receptors (PDGFR) alpha and beta have been suggested as potential targets for treatment of rhabdomyosarcoma, the most common soft tissue sarcoma in children. This study identifies biologic activities linked to PDGF signaling in rhabdomyosarcoma models and human sample collections. Analysis of gene expression profiles of 101 primary human rhabdomyosarcomas revealed elevated PDGF-C and -D expression in all subtypes, with PDGF-D as the solely overexpressed PDGFR beta ligand. By immunohistochemistry, PDGF-CC, PDGF-DD, and PDGFR alpha were found in tumor cells, whereas PDGFR beta was primarily detected in vascular stroma. These results are concordant with the biologic processes and pathways identified by data mining. While PDGF-CC/PDGFR alpha signaling associated with genes involved in the reactivation of developmental programs, PDGF-DD/PDGFR beta signaling related to wound healing and leukocyte differentiation. Clinicopathologic correlations further identified associations between PDGFR beta in vascular stroma and the alveolar subtype and with presence of metastases. Functional validation of our findings was carried out in molecularly distinct model systems, where therapeutic targeting reduced tumor burden in a PDGFR-dependent manner with effects on cell proliferation, vessel density, and macrophage infiltration. The PDGFR-selective inhibitor CP-673,451 regulated cell proliferation through mechanisms involving reduced phosphorylation of GSK-3 alpha and GSK-3 beta. Additional tissue culture studies showed a PDGFR-dependent regulation of rhabdosphere formation/cancer cell stemness, differentiation, senescence, and apoptosis. In summary, the study shows a clinically relevant distinction in PDGF signaling in human rhabdomyosarcoma and also suggests continued exploration of the influence of stromal PDGFRs on sarcoma progression. Cancer Res; 73(7); 2139-49. (C)2013 AACR.
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