[Modified urethral pull-through procedure for posterior urethral stricture or atresia].

OBJECTIVE: To evaluate the feasibility and safety of the modified urethral pull-through procedure for the treatment of posterior urethral stricture or atresia. METHODS: We retrospectively analyzed 212 cases of posterior urethral stricture or atresia treated by the modified urethral pull-through procedure. The length of the stricture or atresia was 1.5 - 12 cm, and 66 cases had experienced 1 - 4 previous unsuccessful urethral repairs. Simple transperineal approach was adopted in 208 cases and transperineal-inferiorpubic approach in the other 4. And 15 of the patients underwent urethral construction with grafts. RESULTS: Satisfactory voiding was achieved in 198 (93.4%) of the patients, of whom 16 received 3 - 15 urethral dilations. Of the 14 cases that failed, 10 succeeded after a second and 2 after a third operation. Of the 15 cases that underwent substitution urethroplasty, 14 achieved satisfactory voiding, and only 1 needed repeat dilation. No serious complications were observed in any of the patients. CONCLUSION: Modified urethral pull-through procedure, with its advantages of safety, mini-invasiveness, simple operation and high success rate, is feasible for the treatment of posterior urethral stricture or atresia, while for that with the length >5 cm, substitution urethroplasty should be considered.

[Expressions of transforming growth factor-beta1 and collagen IV in renal tissues of patients with chronic allograft nephropathy].

OBJECTIVE: To investigate the expressions of transforming growth factor (TGF)-beta1 and collagen IV in the renal tissues of patients with chronic allograft nephropathy (CAN). METHODS: Immunohistochemical method and computer-assisted image analysis system were used to detect the expressions of TGF-beta1 and collagen IV in the renal tissues of patients with CAN, and the association between TGF-beta1 and collagen IV expressions as well as that between their expressions and the pathological grading of CAN were analyzed. RESULTS: The expressions of TGF-beta1 and collagen IV were significantly higher in the renal tissues of the patients than in normal renal tissues (P<0.001), and the expressions tended to increase with the pathological grades of CAN; TGF-beta1 and collagen IV expressions in both the renal glomeruli and the tubulointerstitium were in patients with CAN positively correlated with normal renal tissues (r=0.943, P<0.001; r=0.910, P<0.001). CONCLUSIONS: Abnormal collagen IV deposition is one of the major factors associated with renal fibrosis in CAN, and TGF-beta1 might play an important role in renal fibrosis in CAN through up-regulation of collagen IV in the renal tissues.

[Expression of IGF-I and IGF-IR in bladder cancer].

BACKGROUND & OBJECTIVE: Insulin-like growth factors (IGF) is one of polypeptide growth factors that stimulate proliferation, survival, and differentiation in many cell types; their signal pathways implicate development and progression of many kinds of malignant tumor, while less study were undergone on the roles of IGF-I and IGF-IR in bladder cancer genesis. This study was designed to investigate the expression of IGF-I and IGF-IR and proliferation cell nuclear antigen (PCNA) in human normal and carcinomatous bladder cancer, and to explore the mechanism of IGF-I and IGF-IR in cellular proliferation and tumorigenesis of bladder cancer. METHODS: Immunohistochemical methods were adopted to examine expression of IGF-I, IGF-IR, and PCNA in 88 cases with bladder cancer and 12 cases with normal bladder tissues. The relationship of expression of IGF-I and IGF-IR with various clinicopathological parameters and PCNA were analyzed. RESULTS: The protein expression rates of IGF-I and IGF-IR in bladder cancer were 73.9% and 59.1%, significantly higher than 33.3% and 16.7% in normal tissues, respectively(P< 0.05). Both two protein expression were association with PCNA indexes in bladder cancer (P< 0.05). There were close relationship among IGF-I expression and tumor recurrence (P< 0.05), IGF-IR and tumor grade, stage and recurrence (P< 0.05). CONCLUSION: Abnormality of IGF-I-IGF-IR autocrine loop play an important role in development and progression of bladder cancer by promoting abnormal cellular proliferation. IGF-IR may be a marker for evaluating tumor biological behaviors.

[Correlation between the PTEN/MMAC1/TEP1 expression and cell proliferation and apoptosis in human renal cell carcinoma (RCC)].

BACKGROUND & OBJECTIVE: PTEN is a tumor suppressor gene with phosphatase activity. It had been proved the aberrant expression and mutation of PTEN in diverse types of human cancer; PTEN is closely associated with occurrence and development of malignant tumor. This study was conducted to investigate the expression of PTEN/MMAC1/TEP1 gene product in human renal cell carcinoma (RCC) and the correlation between the expression of PTEN and the biological behaviors of RCC. METHODS: The PTEN protein of 44 cases of RCC tissues confirmed by pathology after operation, 15 cases of adjacent normal renal tissues, and 10 cases of non-tumor normal renal tissues were assessed using immunohistochemical technique (SP). Fifteen RCC tissues and 10 normal renal tissues selected respectively from the renal tissues whose PTEN protein expression were positive as well as those from the negative were made to be the cell suspension mingled with paraffin. The proliferative index and the apoptosis incidence were examined by flow cytometry and the correlation between PTEN protein and the proliferation and apoptosis were analyzed. RESULTS: The expression of PTEN protein was mostly located in the renal cell plasma. The positive incidence of expression PTEN protein in RCC was 36.3% which was prominently lower than those in the adjacent normal tissues (77.3%) and the normal tissues (100.00%) (P< 0.01). There was no significant difference between the different sorts of tissues (P >0.05). The expression of PTEN in stage I, II is much higher than that in stage III, IV(P< 0.05). The proliferative index of RCC whose expression of PTEN protein was positive (5.6+/-0.8)% was significantly lower than that of negative (15.6+/-1.6)% (P< 0.01). While the apoptosis incidence was (6.5+/-1.9)%,which was much higher than that of RCC whose expression was (2.9+/-1.6)% (P< 0.01). CONCLUSION: The positive expression incidence of PTEN protein significantly decreases in RCC tissues. PTEN protein suppresses carcinoma by inducing the cell cycle to be blocked up in G1 phase and increasing the apoptosis incidence. The assessment of the expression PTEN protein is one of the important indexes of the development and prognosis of RCC.