Consistent with the cell lines, in nine matched pairs of prostate tumor and normal prostate samples, we found stronger positive immunostaining of MMP-3 (eight of nine cases, 89%) and MMP-10 (six of nine cases, 67%) in the stromal components of normal prostate tissues than in those of paired malignant tumor tissues (Fig. 3a,b). This evidence concerns the gene MMP3 and prostate neoplasm.