Expression of matrix metalloproteinase-9 and its correlation with tumor interstitial microvascular density and tumor metastasis in transitional cell carcinoma of the bladder

Purpose: To study the expression of matrix metalloproteinase-9 ( MMP-9) and its correlation with interstitial microvascular density(MVD) and tumor metastasis in transitional cell carcinoma of the bladder ( TCCB). Methods: The expression of MMP-9 and MVD were detected in 54 cases of TCCB and 10 cases of normal tissue near the tumor by immunohistochemical technique. Results: In comparison with the above non-tumor normal tissue (20%), the expression of MMP-9 in TCCB (62. 96%) was significantly higher (P 0. 05). MVD was much higher in the group of MMP-9 positive expression than that in the group of MMP-9 negative expression, there was a positive correlation between MMP-9 and MVD(P 0. 05). In addition, the expression of MMP-9 was correlated with histological grade, tumor size and lymph node metastasis (P0. 05), but there was no relationship with age and clinical stage. Conclusions: MMP-9 may promote angiogenesis and play an important role in tumor invasion and metastasis. MMP-9 may be an important indicator to determine biological behavior and prognosis of TCCB.