Expression of matrix metalloproteinases 7 and 2 in human renal cell carcinoma

Matrix metalloproteinases (MMPs) are associated with invasion and metastasis of several malignant tumors in human. Especially so MMP-7, as it is mainly produced by the cancer cell itself. However, the expression of MMP-7 in renal cell carcinoma (RCC) has not been investigated. We examined expressions of MMP-7 and MMP-2 in RCC, and compared them with the clinicopathological characteristics in RCC. Tumor samples from 20 patients with RCC, who had surgery performed at Osaka City University Medical School Hospital, were immunohistochemically stained. Expression of MMP-2 was significantly stronger in advanced stage and in high grade tumors than in low stage and low grade tumors. MMP-7 was also expressed in RCCs, with its expression especially and significantly stronger in high grade than in low grade tumors (p=0.004). However, there was no significant difference of MMP-7 expression between advanced and low stages (p=0.1859). This increased expression of MMP-7 in high grade RCC might be associated with tumor invasion and metastasis.