The tubulin-depolymerising agent combretastatin-4 induces ectopic aster assembly and mitotic catastrophe in lung cancer cells H460
The tubulin-depolymerising agent combretastatin-4 induces ectopic aster assembly and mitotic catastrophe in lung cancer cells H460
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DOI：
10.1007/s10495-008-0200-2
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发表时间：
2008-05-01
期刊：
影响因子：
7.2
通讯作者：
Antoccia, Antonio
中科院分区：
文献类型：
--
作者：
Cenciarelli, Chiara;Tanzarella, Caterina;Antoccia, Antonio
分析了抗有丝分裂药物作用于H460非小肺癌细胞后，微管动力学、中心周围组分拆除与诱导凋亡的关系。微管不稳定剂combretastatin-A4 （CA-4）导致微管排列紊乱、有丝分裂停滞和中期异常，并伴有大量中心体独立的“星形”结构，其中含有微管蛋白和包心体基质成分（如γ -微管蛋白、包心蛋白和九蛋白）的聚集体，而中心粒的结构完整性不受治疗影响。相反，在长时间暴露或高浓度CA-4的条件下，这种聚集体不会形成。7.5 nM CA-4处理产生高频“星形”聚集体，伴随着有丝分裂灾难的发生，其特征是促凋亡Bim蛋白易位到线粒体激活caspase -3/9，以及由于中期停滞时间延长或细胞试图分裂而导致的DNA断裂。不能阻断细胞有丝分裂的药物浓度也不能激活细胞凋亡。细胞周期阻滞和凋亡的详细时间过程分析表明，CA-4洗脱后，具有“星形”结构的中期数量随着时间的推移而减少，阻滞细胞进入后期。4小时后，多个α -微管蛋白和γ -微管蛋白聚集体在双极性有丝分裂纺锤体组织中合并成两个明确的纺锤体。总之，我们的研究结果表明，微管完整性的维持在稳定中心周围基质中起着相关的作用，暴露于微管解聚剂后，中心周围基质的拆除可能与细胞凋亡有关。
The relationship between microtubular dynamics, dismantling of pericentriolar components and induction of apoptosis was analysed after exposure of H460 non-small lung cancer cells to anti-mitotic drugs. The microtubule destabilising agent, combretastatin-A4 (CA-4) led to microtubular array disorganization, arrest in mitosis and abnormal metaphases, accompanied by the presence of numerous centrosome-independent "star-like" structures containing tubulin and aggregates of pericentrosomal matrix components like gamma-tubulin, pericentrin and ninein, whereas the structural integrity of centrioles was not affected by treatment. On the contrary, in condition of prolonged exposure or high concentrations of CA-4 such aggregates never formed. Treatment with 7.5 nM CA-4, which produced a high frequency "star-like" aggregates, was accompanied by mitotic catastrophe commitment characterized by translocation of the proapoptotic Bim protein to mitochondria activation of caspases-3/9 and DNA fragmentation as a result of either prolonged metaphase arrest or attempt of cells to divide. Drug concentrations which fail to block cells at mitosis were also unable to activate apotosis. A detailed time-course analysis of cell cycle arrest and apoptosis indicated that after CA-4 washout the number of metaphases with "star-like" structures decreased as a function of time and arrested cells proceeded in anaphase. After 4 h, the multiple alpha- and gamma-tubulin aggregates coalesced into two well-defined spindles in a bipolar mitotic spindle organization. Overall, our findings suggest that the maintenance of microtubular integrity plays a relevant role in stabilising the pericentriolar matrix, whose dismantling can be associated with apoptosis after exposure to microtubule depolymerising agents.