Identification of PAX3-FKHR-regulated genes differentially expressed between alveolar and embryonal rhabdomyosarcoma: focus on MYCN as a biologically relevant target

Genes Chromosomes Cancer. 2008 Jun;47(6):510-20. doi: 10.1002/gcc.20554.


Rhabdomyosarcoma is a family of myogenic soft tissue tumors subdivided into two main subtypes: alveolar (ARMS) and embryonal (ERMS). ARMS is characterized by a frequent 2;13 chromosomal translocation that creates a PAX3-FKHR fusion transcription factor. To identify downstream targets of PAX3-FKHR, we introduced an inducible form of PAX3-FKHR into human RD ERMS cells. Microarray analysis identified 39 genes (29 upregulated and 10 downregulated) that are modulated by PAX3-FKHR in RD cells and differentially expressed between ERMS and PAX3-FKHR-positive ARMS tumors. Functional annotation demonstrated that genes involved in regulation of transcription and development, particularly neurogenesis, are represented in this group. MYCN was one notable neural-related transcription factor-encoding gene identified in this set, and its regulation by PAX3-FKHR was further confirmed at the RNA and protein levels. The findings of cycloheximide inhibition and time-course studies are consistent with the hypothesis that the PAX3-FKHR protein acts directly on the MYCN gene at the transcriptional level. Functional studies established that MYCN cooperates with PAX3-FKHR to enhance oncogenic activity. In conclusion, we identified a selected set of biologically relevant genes modulated by PAX3-FKHR, and demonstrated that PAX3-FKHR contributes to the expression of MYCN and in turn MYCN collaborates with PAX3-FKHR in tumorigenesis.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor / metabolism
  • Cell Transformation, Neoplastic / genetics
  • Child
  • Cycloheximide / pharmacology
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Mice
  • N-Myc Proto-Oncogene Protein
  • NIH 3T3 Cells / pathology
  • Neoplasm Proteins / biosynthesis
  • Neoplasm Proteins / genetics
  • Nuclear Proteins / physiology*
  • Oligonucleotide Array Sequence Analysis
  • Oncogene Proteins / physiology*
  • Oncogene Proteins, Fusion / physiology*
  • Protein Synthesis Inhibitors / pharmacology
  • RNA Stability
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Neoplasm / genetics
  • RNA, Neoplasm / metabolism
  • Recombinant Fusion Proteins / physiology
  • Rhabdomyosarcoma, Alveolar / genetics*
  • Rhabdomyosarcoma, Alveolar / metabolism
  • Rhabdomyosarcoma, Embryonal / genetics*
  • Rhabdomyosarcoma, Embryonal / metabolism
  • Soft Tissue Neoplasms / genetics*
  • Soft Tissue Neoplasms / metabolism
  • Transcription, Genetic


  • MYCN protein, human
  • N-Myc Proto-Oncogene Protein
  • Neoplasm Proteins
  • Nuclear Proteins
  • Oncogene Proteins
  • Oncogene Proteins, Fusion
  • PAX3-FKHR fusion protein, human
  • Protein Synthesis Inhibitors
  • RNA, Messenger
  • RNA, Neoplasm
  • Recombinant Fusion Proteins
  • Cycloheximide