Inhibition of emodin on growth of human bladder cancer cell BIU87 xenograft in nude mice

Objective: This study aims to investigate the inhibiting effects of emodin on the growth of human bladder cancer cell BIU87 and nude mice with transplanted tumor as well as its mechanism. Methods: The human bladder cancer model was established, which was cell BIU87 xenograft nude mice model. The nude mice were divided into 4 groups, including control group, emodin group, Z-VAD-FMK group and emodin + Z-VAD-FMK group. We measured the tumor diameter and its growth curve. 4 weeks later, all the mice were sacrificed and the tumor tissue was weighted. The apoptosis of the tumor cells was detected by transferase-mediated nick end labeling (TUNEL) method. Immunohistochemistry (IHC) was used to detect NF-K beta and XIAP expression. RT-PCR was conducted to measure NF-K beta and XIAP mRNA expression. Western blot (WB) was used to analyze the expression of NF-K beta and XIAP at the protein level. Results: The tumor was (0.41 +/- 0.05) g in emodin group, which was lighter than emodin + Z-VAD-FMK (0.69 +/- 0.07) g, Z-VAD-FMK (1.04 +/- 0.09) g and control (1.08 +/- 0.13) g groups, significantly (F=90.56/27.49, P<0.01). The cell apoptosis level was higher in emodin group than the other three groups. The results of IHC, RT-PCR and WB showed that emodin could down-regulate the expressions of NF-K beta and XIAP. Conclusions: Emodin could significantly inhibit the in vitro and in vivo growth of human bladder cancer cell BIU87, probably through down-regulating NF-K beta and XIAP to induce cell apoptosis.