Zavrski Ivana, Naujokat Cord, Niemöller Kathrin, Jakob Christian, Heider Ulrike, Langelotz Corinna, Fleissner Claudia, Eucker Jan, Possinger Kurt, Sezer Orhan
Department of Oncology and Hematology, Universitätsklinikum Charité, Humboldt-Universität Berlin, 10098, Berlin, Germany.
J Cancer Res Clin Oncol. 2003 Jul;129(7):383-91. doi: 10.1007/s00432-003-0454-6. Epub 2003 Jul 8.
In this study, we investigated the effects of cell-permeable proteasome inhibitors MG-132, MG-262, PSI, and lactacystin on multiple myeloma cell lines OPM-2, U266, RPMI 8226-S, freshly isolated plasma cells with or without deletion of chromosome 13 from patients with multiple myeloma and plasma cell leukemia, and CD34+ human hematopoietic stem cells. The effects of proteasome inhibitors on cell cycle progression, cell growth, and apoptosis were determined.
MTT-assay was used to examine the cytotoxicity, and annexin-V staining to quantify apoptosis. Cell cycle analyses were performed using 7-ADD and Ki-67 staining by flow cytometry.
PSI was the most potent proteasome inhibitor among those tested with a half maximal cytotoxicity (IC(50)) of 5.7 nM, followed by MG-262, MG-132, and lactacystin. Growth inhibition occurred irrespective of chromosome 13 status. Cell cycle arrest occurred in a dose- and time-dependent manner. Low, subapoptotic dosages led to a partial loss of Ki-67 antigen, whereas apoptotic dosages led to reduced Ki-67 levels. Apoptosis was partially dependent on activation of caspase-3, since Ac-DEVD-cho, a caspase-3 inhibitor, could reduce apoptosis significantly. The cytotoxicity of the four proteasome inhibitors tested was significantly lower in human hematopoietic stem cells than in myeloma cells.
Our results show that proteasome inhibitors induce time- and dose-dependent cell cycle alterations, growth inhibition, and apoptosis in human myeloma cells irrespective of chromosome 13 deletion.
在本研究中，我们研究了细胞可渗透的蛋白酶体抑制剂MG - 132、MG - 262、PSI和乳胞素对多发性骨髓瘤细胞系OPM - 2、U266、RPMI 8226 - S、来自多发性骨髓瘤和浆细胞白血病患者的新鲜分离的有或无13号染色体缺失的浆细胞以及CD34 + 人造血干细胞的影响。测定了蛋白酶体抑制剂对细胞周期进程、细胞生长和凋亡的影响。
采用MTT法检测细胞毒性，用膜联蛋白V染色定量凋亡。通过流式细胞术使用7 - ADD和Ki - 67染色进行细胞周期分析。
在测试的蛋白酶体抑制剂中，PSI是最有效的，其半数最大细胞毒性（IC(50)）为5.7 nM，其次是MG - 262、MG - 132和乳胞素。无论13号染色体状态如何，均出现生长抑制。细胞周期阻滞呈剂量和时间依赖性。低剂量、亚凋亡剂量导致Ki - 67抗原部分丧失，而凋亡剂量导致Ki - 67水平降低。凋亡部分依赖于半胱天冬酶 - 3的激活，因为半胱天冬酶 - 3抑制剂Ac - DEVD - cho可显著降低凋亡。所测试的四种蛋白酶体抑制剂对人造血干细胞的细胞毒性明显低于对骨髓瘤细胞的毒性。
我们的结果表明，蛋白酶体抑制剂在人骨髓瘤细胞中诱导时间和剂量依赖性的细胞周期改变、生长抑制和凋亡，与13号染色体缺失无关。
