Imai Tsuyoshi, Adachi Souichi, Nishijo Koichi, Ohgushi Masatoshi, Okada Masayuki, Yasumi Takahiro, Watanabe Ken-ichiro, Nishikomori Ryuta, Nakayama Tomitaka, Yonehara Shin, Toguchida Junya, Nakahata Tatsutoshi
Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
Oncogene. 2003 Dec 18;22(58):9231-42. doi: 10.1038/sj.onc.1207184.
We investigated the antitumor effects of FR901228, a HDAC inhibitor, on human osteosarcoma cells, in vitro and in vivo to explore its possible utility in the treatment of pediatric bone cancers. FR901228 caused marked growth inhibition with a 50% inhibitory concentration of 1.2-7.3 nM and induction of apoptosis in all eight osteosarcoma cell lines tested. These effects of FR901228 were also observed in vivo xenograft models on BALB/c nude mice, and treatment with 5.6 mg/kg/day resulting in a >70% reduction in the mean final tumor volume compared with the mean initial tumor volume. TUNEL assays demonstrated extensive apoptosis in tumor sections of mice treated with FR901228. Induction of apoptosis was preceded by increased expression of Fas ligand (FasL) mRNA, resulting in expression of membrane-bound FasL, which was followed by sequential activation of caspase-8 and -3. The level of apoptosis induction was reduced using a neutralizing anti-FasL antibody and overexpression of either the dominant-negative FADD or the viral FLICE inhibitory protein. Furthermore, treatment with a suboptimal dose of FR901228 greatly sensitized osteosarcoma cells to agonistic anti-Fas antibody-mediated apoptosis. These findings suggest that FR901228 is a highly promising antitumor agent against osteosarcoma, inducing apoptosis by the activation of the Fas/FasL system.
我们研究了组蛋白去乙酰化酶抑制剂FR901228对人骨肉瘤细胞的体内外抗肿瘤作用，以探索其在儿童骨癌治疗中的潜在应用价值。FR901228对所有测试的8种骨肉瘤细胞系均有显著的生长抑制作用，其半数抑制浓度为1.2 - 7.3 nM，并可诱导细胞凋亡。在BALB/c裸鼠的体内异种移植模型中也观察到了FR901228的这些作用，每天以5.6 mg/kg的剂量给药，与初始平均肿瘤体积相比，最终平均肿瘤体积减少了70%以上。TUNEL分析表明，用FR901228处理的小鼠肿瘤切片中存在广泛的细胞凋亡。细胞凋亡的诱导之前是Fas配体（FasL）mRNA表达增加，导致膜结合FasL的表达，随后依次激活caspase-8和caspase-3。使用中和性抗FasL抗体以及显性负性FADD或病毒FLICE抑制蛋白的过表达可降低细胞凋亡诱导水平。此外，用次优剂量的FR901228处理可使骨肉瘤细胞对激动性抗Fas抗体介导的细胞凋亡高度敏感。这些发现表明，FR901228是一种极具前景的抗骨肉瘤抗肿瘤药物，通过激活Fas/FasL系统诱导细胞凋亡。
