Table of Contents
Definition / general | Interpretation | Diagrams / tables | Clinical features | Microscopic (histologic) images | Molecular / cytogenetics imagesCite this page: Pernick N. EWSR1. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainsewsr1.html. Accessed December 22nd, 2024.
Definition / general
- Ewing sarcoma breakpoint region 1
- At 22q12
- Involved in transcriptional regulation for specific genes and in mRNA splicing
- Plays a role in transcription initiation
- Common fusion partner involved in various tumors (Med Oncol 2013;30:412)
Interpretation
EWSR1 translocations:
- Ewing sarcoma / PNET (soft tissue), Ewing sarcoma (bone): characterized by recurrent translocations involving ESWR1
- t(11;22)(q24;q12): with FLI1 (85% of cases)
- More powerful transcription activator than normal FLI1, can transform NIH 3T3 cells
- t(21;22)(q12;q12): with ERG (Mod Pathol 2012;25:1378)
- Also other molecular partners less frequently (Mod Pathol 2011;24:333)
- Multiple fusion transcripts may coexist in same tumor (Cell Oncol (Dordr) 2013;36:191)
- t(11;22)(q24;q12): with FLI1 (85% of cases)
- Angiomatoid fibrous histiocytoma (Hum Pathol 2013;44:289)
- Clear cell sarcoma (of tendons and aponeuroses)
- Cutaneous myoepithelial tumors: 44% (Mod Pathol 2011;24:1444)
- Desmoplastic small round cell tumor: t(11;22)(p13;q12) with WT1 gene
- Extraskeletal myxoid chondrosarcoma: t(9;22)(q22;q12) seen in 83% (Hum Pathol 2010;41:336)
- Primary pulmonary myxoid sarcoma (Am J Surg Pathol 2011;35:1722)
- Salivary gland hyalinizing clear cell carcinomas: "almost" a defining feature (Am J Surg Pathol 2013;37:571)
- Less common:
- Clear cell sarcoma-like tumor of the gastrointestinal tract (Am J Surg Pathol 2012;36:e1)
- Hemangioma of bone (Am J Surg Pathol 2013;37:613)
- Low-grade fibromyxoid sarcoma (Am J Surg Pathol 2013;37:734)
- Mesothelioma: EWSR1-YY1 appears to be uncommon (Genes Chromosomes Cancer 2013;52:733)
- Myxoid liposarcoma: less common than t(12;16)(q13;p11) (PLoS One 2012;7:e36682)
- Osteosarcoma, small cell variant: rare (Genes Chromosomes Cancer 2011;50:1054)
Clinical features
- EWSR1 binds hepatitis C virus cis-acting replication element (CRE) and is required for efficient viral replication (J Virol 2013;87:6625)
- May exhibit cytoplasmic mislocalization in amyotrophic lateral sclerosis (Hum Mol Genet 2012;21:2899)