Abstract: Objective To observe the influence of VEGF targeted gene silencing of bladder cancer cell line T24 on dendritic cells’ differentiation, maturation and immunity. Methods A lentiviral vector named LV-VEGFA-RNAi(experimental group) for gene silencing targeting VEGF and a lentiviral vector named LV-CON(negative control group) without any valid sequences were constructed. And the blank control group will accept no intervention measures. The expression of VEGF’s mRNA and protein of T24 cells from each group were detected by RT-PCR and ELISA respectively. Then the immature DCs were co-cultured respectively with the supernatant of all the groups mentioned above. CD1a, CD83 as the maturation marker and CD86 as the immunity marker of the DCs were detected by flow cytometry. Results The expression of VEGF’s mRNA and protein of T24 cells in the experimental group was inhibited obviously (P<0.05) compared with that in the negative control group and the blank control group. DCs of the experimental group had an obviously increased(P<0.05) expression of CD1a, CD83 and CD86 compared with the negative control group and the blank control group. Conclusions VEGF targeted gene silencing by RNAi has advantages to the growth and immunity of DCs, which may strengthen the anti-tumor capacity of the DCs by repairing their damaged immune monitoring function.

Key words: bladder cancer, microenvironment, VEGF, DC