The Expression Of β-catenin And Its Clinical Implications In Transitional Cell Carcinoma Of Bladder

PURPOSE:To assesse the expression of β -catenin in transitional cell carcinoma of bladder(BTCC) and evaluate its clinical implications.METHODS: Immunohistochemical staining with streptoavidin peroxidase conjugated method(SP method)was used to measure the expression of β -catenin in 51 cases of patients with transitional cell cancer of bladder and 10 non-malignant bladder mucosa. Stastical analysis was used to investigate the correlation between abnormal expression of β-catenin and several parametres of the patients with BTCC, including clinical stage, pathological grade, tumor reccurence, distant metastasis and the long term survival.RESULTES: All the non-malignant bladder mucosa showed the uniformly positive β-catenin staining at the memberances of epithelial cells. Reduced or loss β-catenin expression was found in 29/51(59.2%) cases of BTCC; in 6/19(31.6%)cases of G1 tumors,in 9/17(64.7%) cases of G2 tumors; in 14/15(80.0%) cases of G3 tumors; in 8/26(34.6%) cases of Ta-T1 tumors; in 21/25(88.0%) cases of T2-T4 tumors respectively. There are statistical significances between the G1-G2 and G3 tumors and between the Ta-T1 and T2-T4 tumors.At the end of follow-up (10~72 months), the rates of recurrenceand distant metastasis are both higher in abnormal expressive cases than in normal ones. Cox proportional hazards model analysis suggested downregulation of p-catenin was an important factor indicating poor prognosis. Conclusion: Reduced or loss of expression of β-catenin in BTCC may affect the tumor diathesis of invasion, recurrence and metastasis. This assay may be used to aid predicting the malignant potentials and the prognosis of BTCC.