Department of Biomedical Engineering, Yuanpei University, Hsinchu, Taiwan.
J Nat Med. 2013 Jan;67(1):98-106. doi: 10.1007/s11418-012-0652-0. Epub 2012 Apr 4.
Tagitinin C, a major sesquiterpenoid, was isolated from the leaves of Tithonia diversifolia. The high morbidity and mortality rate of hepatoma in Taiwan motivated our interest in the investigation of tagitinin C's mechanism against the human hepatocellular carcinoma. The methanolic extract of leaves of T. diversifolia (TDM) and tagitinin C were found to have cytotoxic activities against human hepatoma Hep-G2 cells in the MTT assay with IC(50) values of 40.0 ± 2.0 and 2.0 ± 0.1 μg/mL, respectively. This compound induced population increase in the sub-G(1) phase and S phase arrest. Treatment with tagitinin C isolated from TDM resulted in activation of both caspase 3 and caspase 8 which suggested that the antiproliferative effect of this compound was caspase-dependent apoptosis. Magnetic resonance techniques indicated that the tumorigenisity of xenografts derived from Hep-G2 cells was retarded by the delivery of tagitinin C (15 μg/mouse/day) relative to the control counterparts.
Tagitinin C，一种主要的倍半萜，从 Tithonia diversifolia 的叶子中分离出来。台湾肝癌的高发病率和死亡率激发了我们对 Tagitinin C 抑制人肝癌机制的研究兴趣。从 T. diversifolia（TDM）的叶子中提取的甲醇提取物和 Tagitinin C 在 MTT 试验中对 Hep-G2 细胞表现出细胞毒性，IC50 值分别为 40.0±2.0 和 2.0±0.1 μg/mL。该化合物诱导亚 G1 期细胞群体增加和 S 期阻滞。用 TDM 分离的 Tagitinin C 处理导致 caspase 3 和 caspase 8 的激活，这表明该化合物的抗增殖作用依赖于半胱天冬酶的凋亡。磁共振技术表明，与对照相比，Tagitinin C（15 μg/只/天）的给药可延缓源自 Hep-G2 细胞的异种移植物的致瘤性。
