Damiens E, Baratte B, Marie D, Eisenbrand G, Meijer L
CNRS, Cell Cycle Group, Station Biologique, B.P. 74, 29682 Roscoff cedex, Bretagne, France.
Oncogene. 2001 Jun 28;20(29):3786-97. doi: 10.1038/sj.onc.1204503.
The bis-indole indirubin is the active ingredient of the Traditional Chinese Medicine recipe Danggui Longhui Wan used against chronic myelocytic leukemia. We have previously shown that indirubins are potent inhibitors of cyclin-dependent kinases and glycogen synthase kinase-3. We here investigated the anti-mitotic properties of this class of compounds using the cell permeable indirubin-3'-monoxime and the HBL-100 cell line. Indirubin-3'-monoxime reversibly arrests asynchronous HBL-100 cells in G2. This arrest is not accompanied by any significant change in expression of the major cell cycle regulators. However indirubin-3'-monoxime inhibits the phosphorylation of consensus CDK phosphorylation sites as well as of nucleolin at a specific CDK1/cyclin B phosphorylation site, suggesting a direct action on the mitotic CDK1/cyclin B. When indirubin-3'-monoxime is added to HBL-100 cells synchronized in M phase by nocodazole, cells undergo an endoreplication leading to an 8n DNA content. As soon as indirubin-3'-monoxime is washed away, these polyploid cells become aneuploid and later die from necrosis. This mechanism of endoreplication followed by cell death may contribute to the anti-tumour properties of indirubins.
双吲哚靛玉红是用于治疗慢性粒细胞白血病的中药方剂当归龙荟丸的活性成分。我们之前已表明，靛玉红是细胞周期蛋白依赖性激酶和糖原合酶激酶-3的有效抑制剂。我们在此使用可渗透细胞的靛玉红-3'-单肟和HBL-100细胞系研究了这类化合物的抗有丝分裂特性。靛玉红-3'-单肟使异步HBL-100细胞在G2期可逆性停滞。这种停滞并未伴随主要细胞周期调节因子表达的任何显著变化。然而，靛玉红-3'-单肟抑制共有CDK磷酸化位点以及核仁素在特定CDK1/细胞周期蛋白B磷酸化位点的磷酸化，提示其对有丝分裂CDK1/细胞周期蛋白B有直接作用。当将靛玉红-3'-单肟添加到经诺考达唑同步化至M期的HBL-100细胞中时，细胞会进行核内复制，导致DNA含量达到8n。一旦洗去靛玉红-3'-单肟，这些多倍体细胞就会变成非整倍体，随后因坏死而死亡。这种先核内复制后细胞死亡的机制可能有助于靛玉红的抗肿瘤特性。
