Expression of hypoxia-inducible factor-1α, vascular endothelial growth factor and matrix metalloproteinase-2 in sacral chordomas

Hypoxia-inducible factor-1 alpha (HIF-1 alpha) has been reported to transactivate the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 (MMP-2), which are frequently overexpressed in numerous types of cancer and are known to be significant regulators of angiogenesis. Few studies have investigated the role of these factors in solid tumors, particularly chordomas, which are rare tumors that are thought to originate from notochordal remnants. To clarify whether HIF-1 alpha is involved in angiogenesis in chordoma tissues, we examined the expression of HIF-1 alpha, VEGF and MMP-2 with immunohistochemistry using a tissue microarray containing 35 chordoma samples. The results indicated that HIF-1 alpha, VEGF and MMP-2 are expressed in the majority of chordoma samples. VEGF expression was significantly correlated with HIF-1 alpha and MMP-2 expression, as well as with microvessel density (MVD). However, the prognosis of the chordoma patients was not significantly associated with the expression of these factors, but was associated with MVD. The results therefore showed that there is a correlation between the expression of HIF-1 alpha, VEGF and MMP-2 in chordomas and that the angiogenic process is a potential therapeutic target for chordomas.