Lack of effective T-lymphocyte response to the PAX3/FKHR translocation area in alveolar rhabdomyosarcoma

Cancer Immunol Immunother. 2005 Jun;54(6):526-34. doi: 10.1007/s00262-004-0625-6. Epub 2004 Nov 20.


Purpose: Alveolar rhabdomyosarcoma (ARMS) frequently contains the fusion transcription factor PAX3/FKHR. Therefore, clinical studies have been initiated to utilize the PAX3/FKHR translocation point area as a peptide vaccine against ARMS. Our study was directed at identifying antigenic T-lymphocyte epitopes at the PAX3/FKHR translocation point area.

Experimental design: The peptide sequence surrounding the PAX3/FKHR translocation point was evaluated by MHC binding algorithms for potential T-lymphocyte antigenic epitopes (class I molecules HLA-A1, -A2 and -A3; class II molecules HLA-DR1, -DR4 and -DR7). Using in vitro techniques, dendritic cells loaded with PAX3/FKHR peptides were used to stimulate naive T-lymphocytes. T-lymphocyte activity was then evaluated by 51Cr release and 3H-thymidine uptake assays.

Results: Only one HLA-A3-restricted epitope was predicted by the algorithms. The peptide was prepared and tested for its ability to stimulate naive cytotoxic T-lymphocytes (CTLs). Unfortunately, the peptide was unsuccessful at stimulating naive CTL. However, induction of naive helper T-lymphocytes (HTL) to recognize and respond to the PAX3/FKHR translocation peptide was successful. Yet, this HTL peptide activity did not translate into recognition of PAX3/FKHR-containing ARMS tumor cells.

Conclusions: It appears that the fusion area of PAX3/FKHR may not be a good source of antigenic anti-tumor peptide epitopes. These results raise serious concerns about the success and applicability of future peptide-based vaccine immunotherapy directed at the PAX3/FKHR translocation point.

MeSH terms

  • Amino Acid Sequence
  • Cancer Vaccines / immunology*
  • Cell Line
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / immunology*
  • Forkhead Box Protein O1
  • Forkhead Transcription Factors
  • HLA-A3 Antigen / immunology
  • Humans
  • Molecular Sequence Data
  • PAX3 Transcription Factor
  • Paired Box Transcription Factors
  • Recombinant Fusion Proteins / immunology*
  • Rhabdomyosarcoma, Alveolar / genetics
  • Rhabdomyosarcoma, Alveolar / immunology*
  • T-Lymphocytes / immunology*
  • T-Lymphocytes, Cytotoxic / immunology
  • T-Lymphocytes, Helper-Inducer / immunology
  • Transcription Factors / genetics
  • Transcription Factors / immunology*
  • Translocation, Genetic*


  • Cancer Vaccines
  • DNA-Binding Proteins
  • FOXO1 protein, human
  • Forkhead Box Protein O1
  • Forkhead Transcription Factors
  • HLA-A3 Antigen
  • PAX3 Transcription Factor
  • PAX3 protein, human
  • Paired Box Transcription Factors
  • Recombinant Fusion Proteins
  • Transcription Factors