Expression of PTEN in bladder transitional cell carcinoma and its correlation with phosphorylation of PKB/Akt

Objective:To investigate the clinical significance of phosphatase and tensin homolog deleted on chromosome ten(PTEN)protein exppression and it's correlation with phosphorylation of protein kinase B(PKB/Akt)in human bladder transitional cell Carcinoma(BTCC). Methods:The expression of PTEN and phospho-Akt were detected by SP immunohistochemical technique and Western blotting in 46 cases of BTCC, 13 cases of cystitis glandular and 10 cases of normal bladder tissues, respectively. Results:The positive expression of PTEN in BTCC(60.9%, 0.083±0.018) were significantly lower than those in cystitis glandular and normal bladder tissues(P0.01). The expression level of PTEN was related to the differentiation degree of BTCC and the status of metastasis(P0.05). Western blotting revealed a significant inverse correlation between PTEN and phospho-Akt(r=-0.786,n=46,P0.01).Conclusions:These results indicate that down regulation of PTEN, which may not be able to effectively inhibit the hyperphosphorylation of PKB/Akt, will be an important step in oncogenesis and progression of BTCC.