The cyclin-dependent kinase inhibitor seliciclib (Rroscovitine; CYC202) decreases the expression of mitotic control genes and prevents entry into mitosis
The cyclin-dependent kinase inhibitor seliciclib (Rroscovitine; CYC202) decreases the expression of mitotic control genes and prevents entry into mitosis
复制标题
DOI：
10.4161/cc.6.24.5142
复制
发表时间：
2007-12-15
期刊：
影响因子：
4.3
通讯作者：
Workman, Paul
中科院分区：
文献类型：
--
作者：
Whittaker, Steven R.;Poele, Robert H. te;Workman, Paul
细胞周期蛋白依赖性激酶（CDK）抑制剂seliciclib（R-roscovitine，CYC 202）在临床前模型中显示出有希望的抗肿瘤活性，目前正在进行II期临床试验。seliciclib对CDKs的抑制可能导致细胞周期阻滞和细胞凋亡。然而，药物对基因表达和生化途径产生多重影响是很常见的。为了进一步了解seliciclib的分子药理学，我们使用cDNA微阵列来确定药物在HT 29人结肠癌细胞中诱导的基因表达谱的变化。使用抑制RB磷酸化和细胞增殖的seliciclib浓度。通过蛋白质印迹证实CJUN和EGR 1的mRNA表达增加，这与seliciclib激活ERK 1/2 MAPK通路一致。有丝分裂进程所需的关键基因的转录物显示出显著降低的表达，包括Aurora-A/B（AURK-A/B）、Polo样激酶（PLK）、细胞周期蛋白B2（CCNB 2）、WEE 1和CDC 25 C。在蛋白质水平上也观察到这些有丝分裂基因的表达减少。siRNA介导的Aurora-A蛋白耗竭导致细胞停滞在G（2）/M期，与seliciclib治疗的效果一致。seliciclib处理后，组蛋白H3磷酸化（由Aurora-B催化）减少，有丝分裂标志物（包括磷酸蛋白磷酸酶1 α）表达减少，表明有丝分裂进入受到抑制。结果表明seliciclib阻止进入有丝分裂的潜在机制。基因表达谱分析产生了一些假设，这些假设增加了我们对seliciclib细胞效应的了解，并可以为动物模型和临床试验提供潜在的药效学或反应生物标志物。
The cyclin-dependent kinase (CDK) inhibitor seliciclib (R-roscovitine, CYC202) shows promising antitumor activity in preclinical models and is currently undergoing phase II clinical trials. Inhibition of the CDKs by seliciclib could contribute to cell cycle arrest and apoptosis seen with the drug. However, it is common for drugs to exert multiple effects on gene expression and biochemical pathways. To further our understanding of the molecular pharmacology of seliciclib, we employed cDNA microarrays to determine changes in gene expression profiles induced by the drug in HT29 human colon cancer cells. Concentrations of seliciclib were used that inhibited RB phosphorylation and cell proliferation. An increase in the mRNA expression for CJUN and EGR1 was confirmed by Western blotting, consistent with activation of the ERK1/2 MAPK pathway by seliciclib. Transcripts of key genes required for the progression through mitosis showed markedly reduced expression, including Aurora-A/B (AURK-A/B), Polo-like kinase (PLK), cyclin B2 (CCNB2), WEE1 and CDC25C. Reduced expression of these mitotic genes was also seen at the protein level. siRNA-mediated depletion of Aurora-A protein led to an arrest of cells in the G(2)/M phase, consistent with the effects of seliciclib treatment. Inhibition of mitotic entry following seliciclib treatment was indicated by a reduction of histone H3 phosphorylation, which is catalyzed by Aurora-B, and by decreased expression of mitotic markers, including phospho-protein phosphatase 1 alpha. The results indicate a potential mechanism through which seliciclib prevents entry into mitosis. Gene expression profiling has generated hypotheses that led to an increase in our knowledge of the cellular effects of seliciclib and could provide potential pharmacodynamic or response biomarkers for use in animal models and clinical trials.