Clinical Significance of PTEN Expression in Bladder Cancer / 대한비뇨기과학회지

ABSTRACT

PURPOSE: PTEN (phosphatase and tensin homolog) is a tumor suppressor gene located on the chromosome 10q23. PTEN plays a role in inducing cell cycle arrest and apoptosis. We determined the PTEN expression to evaluate the role of PTEN in aggressiveness and invasiveness of bladder cancer. MATERIALS AND METHODS: PTEN expression was evaluated immunohistochemically in 73 patients with bladder cancer according to grade, stage and lymph node involvement. Cases were considered positive when granular cytoplasmic staining was seen in tumor cells and negative when the tumor tissue was not stained. RESULTS: PTEN was expressed in 50 (68.5%) of 73 patients. In superficial bladder cancer (n=40), 37 patients (92.5%) were positive. Thirteen patients (39.4%) were positive in T2 or higher bladder cancer (n=33). In low grade bladder cancer (n=47), 40 patients (85.1%) were positive. Ten patients (38.5%) were positive in high grade bladder cancer (n=26). PTEN expressions were positive in 1 (11.1%) of 9 lymph node-positive and 12 (50%) of 24 lymph node-negative bladder cancers. CONCLUSIONS: These data demonstrate that loss of PTEN expression has a correlation with aggressiveness and invasiveness in bladder cancer. Therefore, our results suggest that loss of PTEN protein may be a useful marker of poor prognosis in bladder cancer.