Email updates

Keep up to date with the latest news and content from BMC Genomics and BioMed Central.

Open Access Highly Accessed Research article

Diagnostic and prognostic gene expression signatures in 177 soft tissue sarcomas: hypoxia-induced transcription profile signifies metastatic potential

Princy Francis1*, Heidi Maria Namløs2, Christoph Müller2, Patrik Edén3, Josefin Fernebro1, Jeanne-Marie Berner4, Bodil Bjerkehagen4, Måns Åkerman5, Pär-Ola Bendahl1, Anna Isinger1, Anders Rydholm6, Ola Myklebost27 and Mef Nilbert1

Author Affiliations

1 Department of Oncology, Institute of Clinical Sciences, Lund University, Lund, Sweden

2 Department of Tumor Biology, Rikshospitalet – Radiumhospitalet Health Centre, Oslo, Norway

3 Department of Theoretical Physics, Lund University, Lund, Sweden

4 Department of Pathology, Rikshospitalet – Radiumhospitalet Health Centre, Oslo, Norway

5 Department of Pathology, Institute of Clinical Sciences, Lund University, Lund, Sweden

6 Department of Orthopedics, Institute of Clinical Sciences, Lund University, Lund, Sweden

7 Department of Molecular Bioscience, University of Oslo, Norway

For all author emails, please log on.

BMC Genomics 2007, 8:73  doi:10.1186/1471-2164-8-73

Published: 14 March 2007

Abstract

Background

Soft tissue sarcoma (STS) diagnosis is challenging because of a multitude of histopathological subtypes, different genetic characteristics, and frequent intratumoral pleomorphism. One-third of STS metastasize and current risk-stratification is suboptimal, therefore, novel diagnostic and prognostic markers would be clinically valuable. We assessed the diagnostic and prognostic value of array-based gene expression profiles using 27 k cDNA microarrays in 177, mainly high-grade, STS of 13 histopathological subtypes.

Results

Unsupervised analysis resulted in two major clusters – one mainly containing STS characterized by type-specific genetic alterations and the other with a predominance of genetically complex and pleomorphic STS. Synovial sarcomas, myxoid/round-cell liposarcomas, and gastrointestinal stromal tumors clustered tightly within the former cluster and discriminatory signatures for these were characterized by developmental genes from the EGFR, FGFR, Wnt, Notch, Hedgehog, RAR and KIT signaling pathways. The more pleomorphic STS subtypes, e.g. leiomyosarcoma, malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma and dedifferentiated/pleomorphic liposarcoma, were part of the latter cluster and were characterized by relatively heterogeneous profiles, although subclusters herein were identified. A prognostic signature partly characterized by hypoxia-related genes was identified among 89 genetically complex pleomorphic primary STS and could, in a multivariate analysis including established prognostic markers, independently predict the risk of metastasis with a hazard ratio of 2.2 (P = 0.04).

Conclusion

Diagnostic gene expression profiles linking signaling pathways to the different STS subtypes were demonstrated and a hypoxia-induced metastatic profile was identified in the pleomorphic, high-grade STS. These findings verify diagnostic utility and application of expression data for improved selection of high-risk STS patients.