Steroidal saponin RCE-4 from Reineckia carnea( Andr. ) Kunth inhibits growth of human cervical cancer xenograft in nude mice
Yang Xiaojiao;Bai Caihong;Zou Kun;He Haibo;Yu Xiaoqin;Qin Huilin;Zhang Yongfeng;Wang Junzhi;Hubei Provincial Key Laboratory of Natural Products Research and Development,Hubei Institute of Tujia Medicine,Three Gorges University;
Objective To determine the inhibitory effect of steroid sapogenin RCE-4 derived from Reineckia carnea( Andr.) Kunth on the growth of human cervical cancer xenograft in nude mice. Methods Steroidal saponin RCE-4I was extracted and identified by conventional methods. Nude mice model of transplanted tumor of human cervical cancer Caski cells were established by subcutaneously injection of0. 3 m L cells( 4 × 107) under the right hind leg. Caski cervical cancer model mice were randomly divided into model group,paclitaxel( 10 mg / kg) and RCE-4( 25,50 and 100 mg / kg) groups,once a day for 4weeks. Then all mice were sacrificed in 24 h after the final medication,and the volume and weight of transplanted tumor masses were measured to calculate the tumor inhibitory rate. Morphological changes of transplanted tumor tissue were observed by light microscopy,apoptotic rate was determined by TUNEL staining,COX-2 expression in the tumor tissues was detected by immunohistochemical assay,the mRNA levels of Bcl-2,Bax,Caspase-3 and Caspase-9 were detected by real-time PCR,and the Bcl-2 / Bax ratio was analyzed,and the expression level of survivin protein in the tumor tissue was detected by Western blot analysis. Results RCE-4( 25,50 and 100 mg / kg) significantly inhibited the volume and weight of the transplanted tumor in the nude mice( P 0. 05,P 0. 01),up-regulated the mRNA expression levels of Bax,Caspase-3 and Caspase-9,down-regulated the expression of Bcl-2 at mRNA level and COX-2 and survivin at protein level,and reduced the Bcl-2 / Bax ratio( P 0. 05,P 0. 01). Conclusion RCE-4 significantly inhibites the growth of human cervical cancer in nude mice,which may be associated with up-regulating the expression of Bax,Caspase-3 and Caspase-9,and down-regulating the expression of survivin,Bcl-2 and COX-2.