bims-myxlip Biomed News
on Myxoid liposarcoma
Issue of 2022‒04‒24
five papers selected by
Laura Mannarino
Humanitas Research

  1. Oncogenesis. 2022 Apr 22. 11(1): 20
      Myxoid liposarcoma (MLS) represents a common subtype of liposarcoma molecularly characterized by a recurrent chromosomal translocation that generates a chimeric FUS-DDIT3 fusion gene. The FUS-DDIT3 oncoprotein has been shown to be crucial in MLS pathogenesis. Acting as a transcriptional dysregulator, FUS-DDIT3 stimulates proliferation and interferes with adipogenic differentiation. As the fusion protein represents a therapeutically challenging target, a profound understanding of MLS biology is elementary to uncover FUS-DDIT3-dependent molecular vulnerabilities. Recently, a specific reliance on the Hippo pathway effector and transcriptional co-regulator YAP1 was detected in MLS; however, details on the molecular mechanism of FUS-DDIT3-dependent YAP1 activation, and YAP1´s precise mode of action remain unclear. In elaborate in vitro studies, employing RNA interference-based approaches, small-molecule inhibitors, and stimulation experiments with IGF-II, we show that FUS-DDIT3-driven IGF-IR/PI3K/AKT signaling promotes stability and nuclear accumulation of YAP1 via deregulation of the Hippo pathway. Co-immunoprecipitation and proximity ligation assays revealed nuclear co-localization of FUS-DDIT3 and YAP1/TEAD in FUS-DDIT3-expressing mesenchymal stem cells and MLS cell lines. Transcriptome sequencing of MLS cells demonstrated that FUS-DDIT3 and YAP1 co-regulate oncogenic gene signatures related to proliferation, cell cycle progression, apoptosis, and adipogenesis. In adipogenic differentiation assays, we show that YAP1 critically contributes to FUS-DDIT3-mediated adipogenic differentiation arrest. Taken together, our study provides mechanistic insights into a complex FUS-DDIT3-driven network involving IGF-IR/PI3K/AKT signals acting on Hippo/YAP1, and uncovers substantial cooperative effects of YAP1 and FUS-DDIT3 in the pathogenesis of MLS.
  2. Front Pharmacol. 2022 ;13 869754
      Soft tissue sarcomas are a highly heterogenous group of tumors with limited systemic therapy options. Eribulin, a synthetic analogue of halichondrin B, is a potent mitotic inhibitor. A phase 3 trial of previously treated advanced Liposarcoma and Leiomyosarcoma demonstrated superiority of eribulin to dacarbazine. Eribulin appears to be particularly effective for liposarcomas. It has also been shown to be a safe and effective treatment alternative to doxorubicin in patients where doxorubicin is contraindicated. From retrospective studies, eribulin has demonstrated efficacy in patients with angiosarcoma, pleomorphic sarcomas, synovial sarcomas, rhabdomyosarcomas, angiosarcomas, and myxofibrosarcomas. Future areas of development include liposomal eribulin, which may provide increased efficacy and lower toxicity, and delineation of biomarkers of response and resistance, allowing better selection of patients for treatment.
    Keywords:  STS; eribulin; eribulin and related compounds; leiomyosarcoma; liposarcoma; review; sarcoma
  3. Mod Pathol. 2022 Apr 19.
      CIC-rearranged sarcoma is characterized by round cell undifferentiated histology, frequent expression of ETV4 and WT1, and aggressive behavior. A clinical encounter of a case with CIC-DUX4 fusion and ERG/CD31 co-expression prompted us to systematically investigate ERG and CD31 expression status in 30 archival cases of CIC-rearranged sarcoma. Half (15) of them showed moderate or strong ERG expression in <5-100% of tumor cells, among which nine showed heterogeneous membranous CD31 reactivity, including four cases each showing diffuse or strong expression. None of them showed uniformly strong and diffuse ERG/CD31 co-expression; however, three cases were initially interpreted and treated as angiosarcoma without response. Except for smaller superficial tumor enrichment, the clinicopathological characteristics of these nine cases of ERG+/CD31+ CIC-rearranged sarcoma did not differ from those of remaining 21 cases. Five showed focal hemorrhagic clefts/cysts, mimicking vascular spaces. All tumors expressed ETV4 and/or nuclear WT1, and fusion to DUX4 was confirmed in seven cases. Four tumors examined by next-generation sequencing harbored no CIC missense mutations. Using DNA methylation profiling, one CD31+ CIC-rearranged sarcoma was clustered with CD31- CIC-rearranged sarcomas, but distant from angiosarcomas. When compared with epithelioid angiosarcomas lacking CIC rearrangements, ERG+/CD31+ CIC-rearranged sarcomas were distinguished by focal myxoid change and the entire lack of vasoformative architecture. The angiosarcomas were characterized by uniform strong expression of ERG and CD31, but none of them were found positive for ETV4 or nuclear WT1. Heterogeneous ERG/CD31 co-expression in a subset of CIC-rearranged sarcoma is a clinically relevant pitfall for angiosarcoma, as these two diseases are treated differently.
  4. Eur J Histochem. 2022 Apr 22. 66(2):
      Immunotherapy has altered the treatment paradigm for soft tissue sarcomas (STSs). Considering the limited information regarding the clinical significance of immunohistochemical markers in STS, the purpose of this study was to determine the clinical significance of programmed cell death-1 (PD-1), PD ligand-1 (PD-L1), New York esophageal squamous cell carcinoma-1 (NY-ESO-1), and melanoma-associated antigen-A4 (MAGE-A4) expression in STSs. Twenty-two patients (median age, 72.5 years) with STSs treated at our hospital were included in this study. The specimens obtained at the time of biopsy were used to perform immunostaining for PD-1, PD-L1, NY-ESO, and MAGE-A4. The rates of PD-1-, PD-L1-, NY-ESO-, and MAGE-A4-positive cells and cases were calculated. The correlations among the positive cell rates of the immunohistochemical markers as well as their correlations with the histological grade, tumor size, or maximum standardized uptake (SUVmax) value were also determined. The average rates of PD-1-, PD-L1-, NY-ESO-, and MAGE-A4-positive cells were 4.39%, 28.0%, 18.2%, and 39.4%, respectively. Although the PD-1-positive cell rate showed no correlation with the rates of NY-ESO-1- and MAGE-A4-positive cells, the PD-L1-positive cell rates showed strong positive correlations with the rates of NY-ESO-1- and MAGE-A4-positive cells. PD-1-, PD-L1-, NY-ESO-1-, and MAGE-A4-positive cell rates showed weak to moderate correlations with histological grade or tumor size, while the PD-1-, PD-L1-, and MAGE-A4-positive cell rates showed strong to very strong positive correlations with the SUVmax value. Thus, PD-1, PD-L1, NY-ESO, and MAGE-A4 expressions are correlated and may be involved in the aggressive elements of STSs.
  5. Genes Chromosomes Cancer. 2022 Apr 20.
      The year 2021 marked the centenary of the first publication of a cancer termed diffuse endothelioma of bone by James Ewing. Its unique features were apparent even in the first case series he described. This new diagnosis was clearly distinct from osteogenic sarcoma and myeloma, which were already well recognized at the time. We undertake this summary to better understanding Ewing sarcoma, contrasting the logarithmic evolution of the standard of care of systemic therapy for this and related diagnoses to the exponential understanding of the molecular biology of this family of tumors. We also outline in this manuscript how the finding of genomic relatives within Ewing sarcoma itself and related tumors, first noted nearly 40 years ago, helps us appreciate the need to find therapeutic plans that are specific for each small round blue cell tumor subtype. The advent of next generation sequencing regarding previously unknown small round blue cell tumor subtypes in many ways puts us back in the shoes of James Ewing in 1921, searching anew for clues leading to better treatments for increasingly rare cancer subsets. This article is protected by copyright. All rights reserved.
    Keywords:  BCOR-CCNB3; CIC-DUX4; Ewing sarcoma; FET sarcoma; small round cell tumor; systemic therapy; translocation