[49] Distinct MicroRNA Expression Profiles in Synovial Sarcoma and Ewing Family of Tumors

M Hisaoka, A Matsuyama, H Hashimoto. School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan

Background: MicroRNAs (miRNAs) are processed, short non-coding RNAs that can influence a variety of biological processes such as development, proliferation and differentiation. Recently, miRNA expression patterns have been suggested to be closely related to phenotypes and biological behaviors of some epithelial, hematological and mesenchymal malignancies including limited types of soft tissue sarcomas. It is unknown whether miRNA status is also distinct between fusion-associated soft tissue sarcomas with potential overlapping phenotypes such as synovial sarcoma and the Ewing family of tumors.
Design: We performed a comparative analysis of miRNA expression profiles of 15 synovial sarcomas and 5 Ewing sarcomas/primitive neuroectodermal tumors with known tumor-type specific gene fusions using RNA extracted from their frozen tissues and 3D-Gene miRNA microarrays, carrying more than 700 miRNA probes (Toray, Kamakura, Japan). Non-neoplastic adult skeletal muscle tissues (n=5) were used as normal controls.
Results: Unsupervised hierarchical clustering analysis demonstrated unique miRNA expression signatures of both tumor types and control tissues. Using ANOVA and Tukey's multiple comparison, six miRNAs, including let-7e and miR-134, were identified to discriminate each group from others (p<0.038).
Conclusions: Despite the potential overlapping morphologic and immunophenotypic features, synovial sarcoma and the Ewing family of tumors show distinct miRNA profiles. Our data suggests a possible diagnostic role of the miRNA profiling and warrants further investigations of miRNA-dependent molecular mechanisms of the development of these mesenchymal tumors.
Category: Bone & Soft Tissue

Monday, March 9, 2009 1:00 PM

Poster Session II # 10, Monday Afternoon