Purposes: To describe the differential tissue expression of tumor-associated trypsin inhibitor (TATI) in normal bladder urothelium, primary urothelial carcinoma of the bladder (UCB) and metastatic UCB and to assess the association of TATI expression with molecular markers commonly altered in UCB and clinical outcomes after radical cystectomy.
Methods: Slides from eight cystectomy patients without cancer, 191 radical cystectomy patients, 20 lymph nodes without metastasis and 40 lymph nodes with UCB were stained. Tissue expression of TATI, cyclin E1, cyclin D1, p53, p21, p27, pRB, Ki-67, Bcl-2, Caspase-3, Survivin and Cyclooxigenase-2 was measured in a tissue microarray. Cancer-specific and recurrence-free survival after radical cystectomy was recorded.
Results: TATI was expressed in 100% of patients without cancer, while 71% of radical cystectomy specimens and 90% of lymph node metastases exhibited decreased or no TATI expression. In radical cystectomy specimens, TATI expression decreased with advancing pathologic stage (P < 0.001) and lymphovascular invasion (P = 0.055). In univariate analyses, but not in multivariable Cox proportional hazard regression analyses, decreased TATI expression was associated with increased probability of tumor recurrence and cancer-specific mortality. Decreased TATI expression was correlated with altered expression of Cyclooxigenase-2 (P = 0.005), p21 (P = 0.035) and Ki-67 (P = 0.004).
Conclusions: We found that normal urothelium expresses TATI and that TATI expression decreases with advancing tumor stage. While there was no prognostic benefit to TATI when adjusted for standard clinicopathologic features, it seems to play an important biologic role in UCB pathogenesis and invasion. Its association with markers involved in the cell cycle, proliferation and inflammation serves as hypothesis for molecular interactions.