Department of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Acta Pharmacol Sin. 2012 Jan;33(1):109-19. doi: 10.1038/aps.2011.145. Epub 2011 Nov 28.
To elucidate the relationship between triptolide-induced changes in histone methylation and its antitumor effect on human multiple myeloma (MM) cells in vitro.
Human multiple myeloma cell line RPMI8226 was used. Apoptosis was evaluated using Annexin-V-FITC/PI-labeled flow cytometry, Hoechst 33258 staining, and transmission electron microscopy. Flow cytometry was used to detect the cell cycle distribution of the apoptotic cells. The presence of the LSD1, JMJD2B, H3K4me2, H3K9me2, and H3K36me2 proteins was verified by Western blot analysis. Semi-quantitative real-time PCR was performed to examine the expression of LSD1 and JMJD2B.
Triptolide (10-160 nmol/L) suppressed the proliferation of MM cells in a dose- and time-dependent manner with an IC(50) value of 99.2 ± 9.0 nmol/L at 24 h. Triptolide (50 nmol/L) induced G(0)/G(1) cell cycle arrest in MM cells. The agent (50-150 nmol/L) induced apoptosis of MM cells in a dose-dependent manner. The same concentrations of triptolide suppressed the expression of dimethylated H3K4, dimethylated H3K9 and dimethylated H3K36 by altering the expression of histone demethylase LSD1 and JMJD2B without affecting the expression of histone demethylase LSD1.
Triptolide potently inhibits the growth of MM cells via regulating the expression of histone demethylase LSD1 and JMJD2B, which lead to abnormal histone methylation.
阐明雷公藤红素诱导的组蛋白甲基化变化与其在体外抗人多发性骨髓瘤（MM）细胞的作用之间的关系。
采用人多发性骨髓瘤细胞系 RPMI8226。用 Annexin-V-FITC/PI 标记的流式细胞术、Hoechst 33258 染色和透射电子显微镜评估细胞凋亡。用流式细胞术检测凋亡细胞的细胞周期分布。通过 Western blot 分析验证 LSD1、JMJD2B、H3K4me2、H3K9me2 和 H3K36me2 蛋白的存在。通过半定量实时 PCR 检测 LSD1 和 JMJD2B 的表达。
雷公藤红素（10-160 nmol/L）以剂量和时间依赖的方式抑制 MM 细胞的增殖，在 24 小时时 IC50 值为 99.2±9.0 nmol/L。雷公藤红素（50 nmol/L）诱导 MM 细胞 G0/G1 细胞周期停滞。该药物（50-150 nmol/L）以剂量依赖的方式诱导 MM 细胞凋亡。相同浓度的雷公藤红素通过改变组蛋白去甲基酶 LSD1 和 JMJD2B 的表达来抑制二甲基化 H3K4、二甲基化 H3K9 和二甲基化 H3K36 的表达，而不影响组蛋白去甲基酶 LSD1 的表达。
雷公藤红素通过调节组蛋白去甲基酶 LSD1 和 JMJD2B 的表达，导致异常的组蛋白甲基化，从而强烈抑制 MM 细胞的生长。
