Bladder Cancer–Specific Nuclear Matrix Proteins-4 May Be a Potential Biomarker for Non-Muscle-Invasive Bladder Cancer Detection

AIMS: Bladder cancer–specific nuclear matrix protein-4 (BLCA-4) is a protein expressed mainly in bladder cancer tissues. Therefore, the aim of this study was to investigate its assisting diagnostic potential in non-muscle-invasive bladder cancer (NMIBC). METHODS: Twenty patients with NMIBC, 20 with benign prostatic hyperplasia (BPH), and 20 normal controls were included in this study. Blood and urine samples were collected from all patients. Moreover, cancer foci and adjacent tissue samples were collected from NMIBC patients, and normal bladder tissue samples were collected from patients with BPH. A competitive enzyme-linked immunosorbent assay was used to determine the BLCA-4 level in serum and urine, and immunohistochemistry was used to examine BLCA-4 expression in bladder cancer, adjacent, and normal tissues. RESULTS: Median urinary BLCA-4 levels in the NMIBC, BPH, and normal control groups were 0.759 ng/mL, 0.309 ng/mL, and 0.171 ng/mL, respectively. Urinary BLCA-4 level was significantly higher in the NMIBC group than in the other 2 groups (P < 0.01); meanwhile, the BPH group was higher than the normal control group (P < 0.05). Median serum BLCA-4 levels in the NMIBC, BPH, and normal control groups were 5.680 ng/mL, 5.928 ng/mL, and 5.473 ng/mL, respectively, showing no significant difference among groups (P > 0.05). CONCLUSION: As a new marker of bladder cancer, urinary BLCA-4 level detection might apply for clinical diagnosis or postoperative monitoring for NMIBC.