Inoue Yuzuru, Nakayama Yoshifumi, Sako Tatsuhiko, Minagawa Noritaka, Abe Yukio, Nagato Masaru, Kadowaki Koji, Katsuki Takefumi, Matsumoto Kentaro, Tsurudome Yosuke, Shibao Kazunori, Hirata Keiji, Nagata Naoki
Department of Surgery 1, University of Occupational and Environmental Health, School of Medicine, 1-1 Iseigaoka, Yahata-nishi-ku, Kita-kyushu 807-8555, Japan.
In Vivo. 2007 Mar-Apr;21(2):381-7.
4-[3,5-Bis (trimethylsilyl) benzamido] benzoic acid (TAC-101) is a novel retinobenzoic acid derivative which has a specific binding affinity to the retinoic acid receptors (RAR)alpha and RARbeta. Using time-dependent FACScan analysis, it was observed that TAC-101 induced apoptosis in a DLD-1 human colon cancer cell line. In this study, the induction of apoptosis-related proteins and the activities of caspases in a DLD-1 cell line under medication with TAC-101 were investigated.
DLD-1 cells were cultured with different concentrations of TAC-101 for 12, 24 and 48 h. The expressions of Fas, TNF-R1, DR3, bcl-2, Bax and Bid were measured using a Western blot analysis. The activities of caspase-3, -8 and -9 were measured using a colorimetric protease assay kit.
The Western blot analysis showed that TAC-IO1 had almost no effect on the level of Bcl-2, Bax or Bid protein. Although TAC-101 did not change the expression of TNF-R1 and DR3, TAC-101 increased the expression of Fas in both a time- and a dose-dependent manner. A 3-fold increase in caspase-3 activity and a 1.5-fold increase in caspase-8 activity were observed in cells treated with TAC-101 in comparison to the control cells (p<0.01).
Our data indicate that the death receptor root of the apoptotic signal transduction in DLD-1 cells mainly participates in the apoptotic induction of TAC-101. Because the compounds inducing apoptotic activity are frequent targets of cancer therapy, TAC-101 may be a good candidate for use in the treatment of colon cancer.
4-[3,5-双（三甲基硅基）苯甲酰胺基]苯甲酸（TAC-101）是一种新型视黄酸苯甲酸衍生物，对维甲酸受体（RAR）α和RARβ具有特异性结合亲和力。通过时间依赖性流式细胞仪分析，观察到TAC-101可诱导DLD-1人结肠癌细胞系凋亡。在本研究中，研究了TAC-101用药下DLD-1细胞系中凋亡相关蛋白的诱导情况以及半胱天冬酶的活性。
将DLD-1细胞用不同浓度的TAC-101培养12、24和48小时。使用蛋白质免疫印迹分析测量Fas、TNF-R1、DR3、bcl-2、Bax和Bid的表达。使用比色蛋白酶检测试剂盒测量半胱天冬酶-3、-8和-9的活性。
蛋白质免疫印迹分析表明，TAC-101对Bcl-2、Bax或Bid蛋白水平几乎没有影响。尽管TAC-101没有改变TNF-R1和DR3的表达，但TAC-101以时间和剂量依赖性方式增加了Fas的表达。与对照细胞相比，用TAC-101处理的细胞中观察到半胱天冬酶-3活性增加3倍，半胱天冬酶-8活性增加1.5倍（p<0.01）。
我们的数据表明，DLD-1细胞中凋亡信号转导的死亡受体途径主要参与TAC-101的凋亡诱导。由于诱导凋亡活性的化合物是癌症治疗的常见靶点，TAC-101可能是用于治疗结肠癌的良好候选药物。
