Background: Early detection of metastases in muscle-invasive bladder cancer is crucial. Current imaging techniques provide only limited sensitivity for the detection of low volume metastases. Molecular markers and new rapid analysis techniques are therefore needed to improve metastasis detection sensitivity. High urinary matrix metalloproteinase 7 (MMP 7) levels were previously shown to be correlated with the presence of lymph node metastases. In the present study we applied a new innovative antibody-based electrical biochip technology for the quantitative detection of urinary MMP 7.
Materials and methods: Preoperative urine samples were acquired from 30 bladder cancer patients (15xN0 and 15xN1-2) who underwent cystectomy because of muscle-invasive bladder cancer. In addition, urine samples of 15 age-matched healthy individuals were also collected. The MMP 7 analyses were performed using electrical biochip technology and a standard ELISA technique in parallel.
Results: Urinary MMP 7 concentrations measured by biochip technology were significantly higher in patients with metastatic bladder cancer compared to those with organ-confined cancer. The sensitivity for the detection of lymph node metastases was over 70 % using the biochip technology.
Conclusions: These results confirm MMP 7 as a promising metastasis marker in bladder cancer. The new electrical biochip technology provides a rapid and reliable quantitative method for measurement of protein markers in urine.