An office‐based immunodiagnostic assay for detecting urinary nuclear matrix protein 52 in patients with bladder cancer

OBJECTIVE To report the rapid (5 min) and simple detection of a nuclear matrix protein (NMP) in the urine of patients with bladder cancer, using a newly developed office‐based dot‐enzyme‐linked immunosorbent assay (ELISA). PATIENTS AND METHODS Western blot and specific immunoglobulin‐G antibody were used to identify the urinary NMP marker. Urine samples from 149 patients with bladder cancer and 72 controls were evaluated using the developed dot‐ELISA. The initial responses of 43 patients treated by irradiation were followed using the assay. RESULTS The NMP marker was identified in the urine of patients with bladder cancer at 52 kDa (NMP‐52) by Western blot. The dot‐ELISA detected the urinary NMP‐52 marker in 92% of patients with squamous cell carcinoma, 98% with transitional cell carcinoma, and all six of those with adenocarcinoma of the bladder, with a specificity of 94%. The positive and negative predictive values (97% and 94%, respectively) and efficiency (96%) of the dot‐ELISA were high. In addition, the NMP‐52 tumour marker was not detected in the urine of patients who showed a response after radiotherapy. CONCLUSION Detecting the urinary NMP‐52 marker using dot‐ELISA would be helpful in the rapid diagnosis and follow‐up of patients with bladder cancer.