Proteasome inhibitor PS-341 causes cell growth arrest and apoptosis in human glioblastoma multiforme (GBM)
Proteasome inhibitor PS-341 causes cell growth arrest and apoptosis in human glioblastoma multiforme (GBM)
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DOI：
10.1038/sj.onc.1208225
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发表时间：
2005-01-13
期刊：
影响因子：
8
通讯作者：
Koeffler, HP
中科院分区：
文献类型：
--
作者：
Yin, D;Zhou, H;Koeffler, HP
蛋白酶体在控制多种正常细胞和肿瘤细胞的增殖、凋亡和分化中起着关键作用。PS-341是一种新型的抑制26S蛋白酶体活性的硼酸二肽，在体外和体内对多种实体肿瘤有显著的抑制作用。我们用3种人多形性胶质母细胞瘤细胞系和5种原代胶质母细胞瘤外植体研究了其抗增殖、促凋亡的作用。PS-341对GBM细胞系和外植体的增殖有明显的抑制作用。这些细胞发生G2/M细胞周期阻滞，同时S期细胞百分比减少（约2倍），与p21(WAF1), p27（KIP1）以及细胞周期蛋白B1的表达增加以及CDK2， CDK4和E2F4水平降低有关。Annexin V分析显示，PS-341作用时间（10(-7)M, 24-48 h）约有35-40%的细胞发生凋亡；与这些发现一致，免疫印迹显示聚adp核糖聚合酶（PARP）的c端85 kDa凋亡片段，Bcl2和Bcl-xl水平降低。PS-341在治疗早期下调Bcl-2和Bcl-xl蛋白水平的表达。这些变化的发生与细胞的p53突变状态无关。PS-341激活GBM细胞中的JNK/c-Jun信号，JNK抑制剂SP600125阻断JNK信号，部分逆转PS-341的生长抑制作用。Western blot结果显示，PS-341 （10(-7) M, 24 h）降低了细胞核NF-kappaB水平，报告基因检测结果显示，PS-341降低了这些转化细胞中NF-kappaB的转录活性。此外，PS-341增强TRAIL （tnf相关的凋亡诱导配体）和TNFalpha（肿瘤坏死因子α）诱导GBM细胞死亡和凋亡（2 - 5倍）。综上所述，PS-341对GBM细胞的生长和凋亡具有深远的影响，提示PS-341可能是胶质瘤患者的有效治疗方法。
The proteasome plays a pivotal role in controlling cell proliferation, apoptosis, and differentiation in a variety of normal and tumor cells. PS-341, a novel boronic acid dipeptide that inhibits 26S proteasome activity, has prominent effects in vitro and in vivo against several solid tumors. We examined its antiproliferation, proapoptotic effects using three human glioblastoma multiforme (GBM) cell lines and five primary GBM explants. PS-341 markedly inhibited proliferation of GBM cell lines and explants in liquid and soft agar culture. These cells developed a G2/M cell cycle arrest with a concomitant decreased percentage of cells in S phase (approximate to2-fold), associated with an increased expression of p21(WAF1), p27(KIP1), as well as cyclin B1 and decreased levels of CDK2, CDK4, and E2F4. About 35-40% of the cells became apoptotic when exposed to PS-341 (10(-7) M, 24-48 h) as shown by Annexin V analysis; in concert with these findings, immunobloting showed a C-terminal 85 kDa apoptotic fragment of poly ADP-ribose polymerase (PARP), and a decreased level of Bcl2 and Bcl-xl. PS-341 downregulated the expression of Bcl-2 and Bcl-xl in protein levels at an early time of treatment. These changes occurred irrespective of the p53 mutational status of the cells. PS-341 activated JNK/c-Jun signaling in GBM cells, and the JNK inhibitor SP600125 blocked the JNK signaling to reverse partially the PS-341 growth inhibition. PS-341 (10(-7) M, 24 h) decreased nuclear NF-kappaB levels as shown by Western blot, and reduced transcriptional activity of NF-kappaB as measured by reporter assays in these transformed cells. Also, PS-341 enhanced TRAIL (TNF-related apoptosis-inducing ligand) and TNFalpha (tumor necrosis factor alpha) induced cell death and apoptosis (two-to-five-fold) in GBM cells. In summary, PS-341 has profound effects on growth and apoptosis of GBM cells, suggesting that PS-341 maybe an effective therapy for patients with gliomas.