Mechanism of immune escape in renal cell carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of immune escape in renal cell carcinoma(RCC).</p><p><b>METHODS</b>Fas and FasL expressions were examined by immunohistochemical technique in 44 RCC patients, with the Ki67 expression and apoptosis of tumor infiltrating lymphocytes(TIL) monitored simultaneously. Cytokines including IL2 and IFN alpha were used to induce the expression of the renal carcinoma cell lines 786-0 cells. Combination treatment of 786-0 with cytokines and Anti-Fas monoclonal antibody (FasAb) was used to induce apoptosis. FasL function was assessed by in vitro co-culture assays using renal cancer cells 786-0 and Fas-sensitive Jurkat T-cells.</p><p><b>RESULTS</b>(1) Fas expression rate in RCC(22.8%) was lower than that in the controlled normal kidney tissues(53.8%, P < 0.01). FasL expression rate in RCC (46.5%) was higher than that in the controlled normal kidney tissues (23.2%, P < 0.01). That of Ki67 was 32.8%, with the expressions of Fas and Ki67 showing a negative correlation (r = -0.62, P < 0.05). In contrast, the expressions of FasL and Ki67 showed a positive correlation. (r = 0.93, P < 0.01). The Fas expression of stage I was significantly higher than that of stages III and IV. The expression rate of FasL in RCC was significantly increased with RCC stage (P < 0.01). (2) The apoptotic rate of TIL in RCC (33.9%) was significantly higher than that of the normal kidney tissues (3.5%, P < 0.01). The expression of FasL and the apoptotic rate of TIL in RCC gave a positive correlation (r = 0.96, P < 0.01). (3) Fas expression rate in 786-0 cells was 13.7%. The apoptotic rate mediated by FAsAb was 9.6%. IFN alpha was able to up-regulate the Fas expression and subsequently augment the FasAb-mediated apoptosis in 786-0 cells. But IL2 did not show similar effects. (4) The FasL expression rate of 786-0 was 18.6%. FasL expressed by 786-0 cells was able to induce apoptosis of Jurkat T-cells in co-culture assays and the apoptosis of Jurkat T-cells was significantly lowered after blocking the effect of FasL with Fas-neutralizing antibody NOK-2, giving the apoptotic rates of 14.9% and 2.0%, respectively, the difference therein is statistically significant (P < 0.01).</p><p><b>CONCLUSION</b>Down-regulation of Fas expression and up-regulation of FasL-expression are the mechanisms through which the RCC cells escape from immune attack.</p>

Alternate intravesical instillation of different agents for the prevention of bladder cancer recurrence / 中华泌尿外科杂志

Objective To evaluate the alternate intravesical instillation of MMC and IL 2 together with BCG for the prevention of bladder cancer recurrence. Methods The instillation was carried out for 41 cases of bladder cancer after surgical management.All the patients have been followed up for 38～66 months with an average of 50 months.TNFa levels were periodically detected after the instillation. Results No recurrence has been noted in all the 34 patients of Ta,T 1 and T 2 tumors except 1 with mixed squamous cancer. 3 of 7 T 3 cases underwent TURBT,recurrence was noted in 2 and the TNFa remained much higher after the instillation. Conclusions Alternate intravesical instillation of MMC and IL 2 together with BCG is an effective means of preventing bladder cancer recurrence.TNFa detection might serve as a marker for bladder cancer recurrence.

Investigation on immune tolerance induced by portal venous inoculation of donorspleen cells combined the CsA / 中国免疫学杂志

With the hereotopic heart transplantation, immune tolerance induced by portal venous inoculation of donor spleen cells was studied.Methods:The recipient rats received donor spleen cells through portal vein combined with of cyclosporine A(CsA).The NK cell activity and IL-2, IFN-y expression of recipient spleen cells were detected. Results: Hie inoculation of donor spleen cells through the portal vein could significandy prolong survival time of heart allografts.IL- 2, IFN-y expression of recipient spleen lymphocytes and the recipient NK cell activity was also inhibitied.Conclusion:The inoculation of donor spleen cells through the portal vein could induce immune tolerance.The suppression of IL-2-NK-IFN-y immunologic net may be an important mechanism of portal vein tolerance.