Expression and Significance of NDRG-1 and MMP-7 in Renal Cell Carcinoma

Objective To investigate the expression of N-myc down regulated gene-1(NDRG-1) and matrix metalloproteinase-7 (MMP-7) in renal cell carcinoma(RCC),and the relation to clinicopathologic factors and patient prognosis. Methods High sensitive SP immunohistochemistry was used to detect the expressions of NDRG-1 and MMP-7 in 78 cases of renal cell cancer and its adjacent tissues. Results The proportion of NDRG-1-expressing tumor cells(52.6%) was significantly lower than that of normal cells(100%)（P<0.05）.The abnormal expression of NDRG-1 correlated with tumor size,renal vein tumor thrombus,metastasis,renal pelvis invasion,histological grade and clinical stage（P<0.05）.However,the proportion of MMP-7-expressing tumor cells(55.1%) was significantly higher than that of normal cells (almost no expression).The abnormal expression of MMP-7 correlated with capsular invasion,metastasis,histological grade and clinical stage(P< 0.05).Negative expression of NDRG1 and positive expression of MMP-7 in RCC were strong predictors of poor prognosis respectively（P=0.001）.There was no correlation between the expression of NDRG-1 and MMP-7 in RCC（rs=-0.198，P=0.082）. Conclusion The low expression of NDRG-1 and high expression of MMP-7 correlate with the invasion,metastasis and patient survival.Our results suggest that NDRG1 and MMP-7 may be two potential targets for determining the degree of malignancy,prognosis and early detection of renal cell carcinoma.