The expression and prognostic significance of proliferation cell nuclear antigen, cytokeratin-7 and cytokeratin-20 in bladder cancer

Abstract

Objective To investigate the expression of proliferation cell nuclear antigen (Ki-67), cytokeratin-7 (CK7) and cytokeratin-20 (CK20) in bladder cancer and its prognostic significance. Methods The expression of Ki-67, CK20 and CK7 in 138 cases of bladder cancer tissue was detected by immunohistochemical SP method. The clinical follow-up data were analyze. Results Ki-67, CK7 and CK20 was highly expressed in bladder cancer tissues, with the positive rate of 82.6%, 88.4% and 78.3% respectively. The expression of Ki-67 in bladder cancer was significantly associated with grading (P=0.010), staging (P=0.007), recurrence (P=0.044) and metastasis (P=0.037). The expression of CK7 in bladder cancer was significantly associated with grading (P=0.002), staging (P=0.043), metastasis (P=0.012) and histological type (P=0.020). The expression of CK20 in bladder cancer was significantly associated with gender, grading, with gender (P=0.001), grading (P=0.012), staging (P=0.021), tumor size (P=0.034) and tumor recurrence (P=0.035). Spearman rank analysis showed that Ki-67 and CK20 had positive correlation (P=0.026), so as CK20 and CK7 (P=0.010). But Ki-67 and CK7 have no correlation (P=0.319). The median progression-free survival of patients positive or negative for Ki-67 was 10 and 21 months, respectively. Kaplan-Meier survival analysis revealed that the difference was statistically significant (P=0.000). The median progression-free survival of patients positive or negative for CK7 was 13 and 9 months, respectively. Kaplan-Meier survival analysis demonstrated that the difference was not statistically significant (P=0.074). The median progression-free survival of patients positive or negative for CK20 was 9 and 18 months, respectively. Kaplan-Meier survival analysis illustrated that the difference was statistically significant (P=0.000). Conclusion Along with the increase of tumor grade and stage, the expression of Ki-67 and CK20 in bladder cancer tissues was up-regulated, and CK7 down-regulated. All of them are involved in the advent and development of bladder cancer. Key words: Bladder cancer; Proliferation cell nuclear antigen; Cytokeratin-7; Cytokeratin-20; Prognosis