Expression of decorin, a small leucine-rich proteoglycan, as a prognostic factor in soft tissue tumors

Background and Objectives: Decorin is a major extracellular matrix protein which has recently become the focus of various cancer studies. However, there have so far been no reports describing the clinicopathological implications of decorin in soft tissue tumors. The aim of this study was to examine whether decorin expression is a prognostic factor in soft tissue tumors. Methods: Decorin expression was examined in 85 samples obtained from 77 patients by real-time quantitative PCR and immunohistochemistry. Results: Lower levels of decorin were expressed in liposarcoma and malignant peripheral nerve sheath tumor than in lipoma (< 0.01) and neurofibroma (P < 0.05), respectively. An immunohistochemical analysis for spindle-cell sarcomas demonstrated decorin protein to be produced by myofibroblastic cells in the peripheral stromal extracellular spaces. On a Kaplan-Meier analysis, lower levels of decorin were associated with lower disease-free and overall survival rates (P < 0.05) in 31 spindle-cell sarcomas. A multivariate analysis revealed a significant correlation between a reduced decorin expression and a poor disease-free survival (P = 0.04). In all seven patients with recurrent or metastatic lesions, the decorin expression levels were lower in secondary lesions than in primary lesions. Conclusions: A reduced decorin expression was found to be a useful biomarker of aggressiveness in soft tissue tumor.