Noninvasive diagnosis of bladder cancer by detection of matrix metalloproteinases (MMP-2 and MMP-9) and their inhibitor (TIMP-2) in urine

Abstract

Objectives: TIMPs control the activity of MMPs, one of the key molecules for tumor invasion and metastasis. The aim of this study was to assess the usefulness of MMP-2 and MMP-9 in relation to their inhibitor (TIMP2) as noninvasive diagnostic tests for bilharzial bladder cancer.

Material and methods: Voided urine samples were provided from 244 subjects (154 bladder cancer [136 bilharzial]; 60 benign urologic disorders; 30 healthy volunteers). Urine sediment was used for cytology, and the supernatant for estimation of MMPs and TIMP-2 by ELISA and gelatin zymography.

Results: The best cut-off values for the investigated markers were determined by ROC curve. Positivity rates and median levels for MMP-2, MMP-9, TIMP-2, MMP-2/TIMP-2, and MMP-9/TIMP-2 showed significant difference among the three investigated groups (p<0.001). MMP-9 and MMP-2/TIMP-2 were related to pathologic type, MMP-2/TIMP-2 was inversely related to the grade, and MMP-9/TIMP-2 was related to bilharziasis (p<0.05). MMP zymography results were comparable to those from ELISA.

Conclusion: The sensitivity and specificity of MMP zymography, MMP-9/TIMP-2 ratio, and MMP-2/TIMP2 ratio were superior among all investigated parameters; furthermore, combined testing of cytology with them improves the sensitivity even in superficial and low-grade tumors.