Ewing sarcoma breakpoint region 1-ETS transcription factor ERG fusion protein-derived peptides presented on Major Histocompatibility Complex (EWS-ERG-MHC)

The EWS-ERG fusion protein-derived peptides presented on the Major Histocompatibility Complex (MHC) represent a class of tumor-specific neoantigens resulting from the t(21;22)(q22;q12) chromosomal translocation. This genetic rearrangement, found in approximately 5-10% of Ewing sarcoma cases, fuses the EWSR1 gene with the ERG gene, creating a chimeric transcription factor that drives oncogenesis (PubMed: 25151357). The unique amino acid sequence at the fusion junction is processed by the proteasome and presented as short peptides on the cell surface by MHC class I molecules (PubMed: 33024105). These complexes are ideal targets for precision immunotherapy because they are absent in normal tissues, potentially reducing the risk of on-target, off-tumor toxicity. Current therapeutic strategies focusing on this target include the development of T-cell receptor (TCR) engineered T-cells and peptide-based vaccines designed to elicit a robust cytotoxic T-lymphocyte response against the tumor (PubMed: 31160318). However, challenges such as low antigen density and the heterogeneity of HLA expression in tumors remain significant hurdles for clinical efficacy.

Other names

EWS-ERG neoantigenEWSR1-ERG fusion peptidesEWS-ERG breakpoint peptidesEWS-ERG-MHC complex

T-cell receptor (TCR) recognition of the specific peptide-MHC complex on the tumor cell surface, triggering T-cell activation, cytokine release, and cytotoxic lysis of the cancer cell (PubMed: 31160318).