Molecular detection of uroplakin II in the peripheral blood of patients with urothelial carcinoma of the urinary bladder

To investigate the clinical value of' nested reverse transcription polymerase chain reaction [RT-PCR] of uroplakin II [UP-Il] in cells separated from the peripheral blood of' patients with urothelial cancer. The study included 45 patients with urothelial cancer, 7 apparently healthy subjects. 5 patients with untreated cystitis. and 3 patients with untreated renal cell carcinomas. Patients were divided into three groups. including 7 patients with superficial disease [group I]. 18 patients with invasive disease [group II] aid 20 patients with metastatic disease [group III]. Follow up samples were obtained after receiving 4 cycles of chemotherapy from 10 metastatic patients to evaluate the effect of chemotherapy on detection of UP-Il positive cells in the peripheral blood. Detection of circulating UPIL-mRNA-positive cells in the peripheral blood of' urothelal cancer patients was done by nested UP II-mRNA. UPIL mRNA-specific PCR products was detected in I [14.3%] of 7 patients with superficial cancers, in 8[44.4%] of 18 patients with musculary invasive disease and in 9 [45%] of 20 patients with metastatic cancer [p<0.05]. Within the metastatic group UPLI was positive in 4 [36.4%] of II patients with lymph node metastases and in 5 [55.6%] of 9 patients with distant metastases. As regards the grades of the urothelial cancers . nested RT-PCR for UP-Il was positive in 30% of grade I. in 3 1.8% of grade II and in 61.5% of' grade III. Two of the 10 metastatic patients who received systemic chemotherapy showed disappearance of UP-Il positive cells in their blood. As regards the control group. none showed positive expression of U P-Il by the nested RT-PCR in the peripheral blood. Expression of UPII mRNA was detected in 18 primary and in 6 metastatic transitional cell carcinoma [TCC] of patients and not detected in a bladder squamous cell carcinoma and in 3 renal cell carcinomas. Nested reverse transeriptmon-PCR assay for UP-Il is highly specific and might he used as a molecular tumor marker for staging of' urothelial cancers