Ewing sarcoma is characterized by pathognomonic translocations, most frequently fusing
with
. An estimated 30% of Ewing sarcoma tumors also display genetic alterations in
,
, or
(
). Numerous ...attempts to develop relevant Ewing sarcoma models from primary human cells have been unsuccessful in faithfully recapitulating the phenotypic, transcriptomic, and epigenetic features of Ewing sarcoma. In this study, by engineering the t(11;22)(q24;q12) translocation together with a combination of SPC mutations, we generated a wide collection of immortalized cells (EWIma cells) tolerating EWSR1-FLI1 expression from primary mesenchymal stem cells (MSC) derived from a patient with Ewing sarcoma. Within this model,
alterations strongly favored Ewing sarcoma oncogenicity. Xenograft experiments with independent EWIma cells induced tumors and metastases in mice, which displayed
features of Ewing sarcoma. EWIma cells presented balanced but also more complex translocation profiles mimicking chromoplexy, which is frequently observed in Ewing sarcoma and other cancers. Collectively, these results demonstrate that bone marrow-derived MSCs are a source of origin for Ewing sarcoma and also provide original experimental models to investigate Ewing sarcomagenesis. SIGNIFICANCE: These findings demonstrate that Ewing sarcoma can originate from human bone-marrow-derived mesenchymal stem cells and that recurrent mutations support EWSR1-FLI1 translocation-mediated transformation.
Indirect somatic genetic rescue (SGR) of a germline mutation is thought to be rare in inherited Mendelian disorders. Here, we establish that acquired mutations in the EIF6 gene are a frequent ...mechanism of SGR in Shwachman-Diamond syndrome (SDS), a leukemia predisposition disorder caused by a germline defect in ribosome assembly. Biallelic mutations in the SBDS or EFL1 genes in SDS impair release of the anti-association factor eIF6 from the 60S ribosomal subunit, a key step in the translational activation of ribosomes. Here, we identify diverse mosaic somatic genetic events (point mutations, interstitial deletion, reciprocal chromosomal translocation) in SDS hematopoietic cells that reduce eIF6 expression or disrupt its interaction with the 60S subunit, thereby conferring a selective advantage over non-modified cells. SDS-related somatic EIF6 missense mutations that reduce eIF6 dosage or eIF6 binding to the 60S subunit suppress the defects in ribosome assembly and protein synthesis across multiple SBDS-deficient species including yeast, Dictyostelium and Drosophila. Our data suggest that SGR is a universal phenomenon that may influence the clinical evolution of diverse Mendelian disorders and support eIF6 suppressor mimics as a therapeutic strategy in SDS.
Monogenic interleukin-10 (IL-10) and IL-10 receptor (IL-10R) deficiencies cause very early onset severe inflammatory bowel disease. Here, we report that 5 patients with an IL-10R1 (n = 1) or IL-10R2 ...(n = 4) deficiency developed B-cell non-Hodgkin lymphoma between the ages of 5 and 6 years (which was recurrent in 1 patient). These lymphomas had some of the characteristics of diffuse large B-cell lymphomas and contained monoclonal, Epstein-Barr virus–negative germinal center B cells. The tumors displayed a remarkably homogeneous signature, with original activation of the nuclear factor κB pathway and a decrease in intratumor T-cell infiltration. Hence, IL-10R deficiency is associated with a high risk of developing B-cell lymphoma. Our results revealed an unexpected role of the IL-10R pathway in lymphomagenesis.
•Human inherited IL-10 receptor deficiency is associated with a very high risk of non-EBV–related diffuse large B-cell lymphoma.•IL-10 signaling may be involved in the immune control of germinal center B-cell lymphoma.
The reintegration of excised signal joints resulting from human V(D)J recombination was described as a potent source of genomic instability in human lymphoid cancers. However, such molecular events ...have not been recurrently reported in clinical patient lymphoma/leukemia samples. Using a specifically designed NGS-capture pipeline, we here demonstrated the reintegration of T-cell receptor excision circles (TRECs) in 20/1533 (1.3%) patients with T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL). Remarkably, the reintegration of TREC recurrently targeted the tumor suppressor gene, ZFP36L2, in 17/20 samples. Thus, our data identified a new and hardly detectable mechanism of gene deregulation in lymphoid cancers providing new insights in human oncogenesis.
The objective of this study was to assess the clinical impact and financial costs of next‐generation sequencing (NGS) in 5 categories of pediatric and adult hematological cancers. NGS prescriptions ...were prospectively collected from 26 laboratories, with varied technical and reporting practice (all or only significant targets). Impact was defined by the identification of (1) an actionable mutation, (2) a mutation with prognostic and/or theranostic value, and/or (3) a mutation allowing nosological refinement, reported by local investigators. A microcosting study was undertaken in 4 laboratories, identifying the types and volumes of resources required for each procedural step. Individual index prescriptions for 3961 patients were available for impact analysis on the management of myeloid disorders (two thirds) and, mainly mature B, lymphoid disorders (one third). NGS results were considered to impact the management for 73.4% of prescriptions: useful for evaluation of prognostic risk in 34.9% and necessary for treatment adaptation (actionable) in 19.6%, but having no immediate individual therapeutic impact in 18.9%. The average overall cost per sample was 191 € for the restricted mature lymphoid amplicon panel. Capture panel costs varied from 369 € to 513 €. Unit costs varied from 0.5 € to 5.7 € per kb sequenced, from 3.6 € to 11.3 € per target gene/hot‐spot sequenced and from 4.3 € to 73.8 € per target gene/hot‐spot reported. Comparable costs for the Amplicon panels were 5–8 € per kb and 10.5–14.7 € per target gene/hot‐spot sequenced and reported, demonstrating comparable costs with greater informativity/flexibility for capture strategies. Sustainable funding of precision medicine requires a transparent discussion of its impact on care pathways and its financial aspects.