Impact of c-Met expression on angiogenesis in soft tissue sarcomas: correlation to microvessel-density

The c-Met protein is significant for oncogenesis and angiogenesis within the c-Met/HGF/SF-mediator system. The aim of this study was the analysis of c-Met immunoexpression/-synthesis and microvessel density as parameters for angiogenesis and prognosis in 115 soft tissue sarcomas.

C-Met could be detected by immunohistochemistry in 87% of sarcomas. In all, 60.9% of cases exhibited absent or faint expression of c-Met protein, and 39.1% high expression of c-Met protein with a correlation between tumor grading and c-Met immunoexpression. Using in situ hybridization with detection of c-met-mRNA-transcripts, c-Met protein synthesis within tumor cells could be demonstrated. A statistically significant correlation between c-Met immunoexpression and tumor microvessel density was found. No prognostic value of c-Met expression and microvessel density could be detected in 56 patients with clinical follow-up ( P=0.8506 and P=0.9329 for disease-free survival).

The results underline a role of c-Met as an oncoprotein in soft tissue sarcomas with correlation between immunoexpression and grading. The statistically significant correlation between c-Met expression and microvessel density (as a parameter of tumor angiogenesis) suggests an angiogenic function of the c-Met/HGF/SF mediator system in malignant mesenchymal tumors.