Thati Bhumika, Noble Andy, Creaven Bernadette S, Walsh Maureen, Kavanagh Kevin, Egan Denise A
Centre for Pharmaceutical Research & Development, Institute of Technology, Tallaght, Dublin 24, Ireland.
Chem Biol Interact. 2007 Jun 30;168(2):143-58. doi: 10.1016/j.cbi.2007.04.003. Epub 2007 Apr 19.
The central objective of the current study was to investigate the potential in vitro anti-proliferative properties of the parent ligand, coumarin-dioxy-acetic acid (cdoaH(2)), and its copper complex, copper-coumarin-dioxyacetic acetate-phenathroline ([Cu(cdoa)(phen)(2)]) using four human-derived model cell lines, two neoplastic and two non-neoplastic. In addition, selected mechanistic studies were carried out using one of the neoplastic-derived model cell lines, Hep-G2. Results obtained show that the complex, rather than the ligand, could alter the proliferation of both human neoplastic renal (A-498) and hepatic (Hep-G2) cells. Furthermore, hepatic non-neoplastic cells (Chang) appeared to be less sensitive. However, this effect was not mirrored in non-neoplastic renal (HK-2) cells, a profile shared with cisplatin. The observed anti-proliferative effect appeared to be concentration- and time-dependant, and could be attributed to the complex, rather than any of the component parts, i.e. 1,10-phenanthroline, the coumarin ligand, or the simple metal salt. Furthermore, the complex was shown to decrease DNA synthesis, but did not intercalate with it. Based on IC(50) values, [Cu(cdoa)(phen)(2)] was shown to be almost six times more potent than cisplatin. Moreover, there was no evidence to show that P-glycoprotein (P-gp)-mediated multi-drug resistance (MDR) was likely to play a role in decreasing the anti-proliferative activity of the complex. Cytological stains, analysis of genomic DNA, and biochemical assays [caspase-3 and -9 and cleaved poly(ADP-ribose)-polymerase protein], suggested that cell death could switch between apoptosis and necrosis, and this effect appeared to be concentration-dependent. Additionally, flow cytometric analysis showed that the complex functioned through an alteration in cell cycle progression. Taken together, [Cu(cdoa)(phen)(2)] has been shown to be a more potent anti-proliferative agent than either the ligand or cisplatin, and is capable of altering key biochemical events leading to the execution of apoptotic and/or necrotic cell death, suggesting that it is worthy of further investigation.
本研究的核心目标是使用四种人源模型细胞系（两种肿瘤细胞系和两种非肿瘤细胞系），研究母体配体香豆素 - 二氧乙酸（cdoaH₂）及其铜配合物铜 - 香豆素 - 二氧乙酸 - 菲咯啉（[Cu(cdoa)(phen)₂]）的体外抗增殖特性。此外，使用其中一种肿瘤来源的模型细胞系Hep - G2进行了选定的机制研究。所得结果表明，是配合物而非配体能够改变人肿瘤性肾细胞（A - 498）和肝细胞（Hep - G2）的增殖。此外，肝非肿瘤细胞（Chang细胞）似乎不太敏感。然而，这种效应在非肿瘤性肾细胞（HK - 2）中并未体现，这一情况与顺铂相同。观察到的抗增殖效应似乎具有浓度和时间依赖性，且可归因于配合物，而非任何组成部分，即1,10 - 菲咯啉、香豆素配体或简单金属盐。此外，该配合物被证明可减少DNA合成，但不会与之嵌入结合。基于半数抑制浓度（IC₅₀）值，[Cu(cdoa)(phen)₂]的效力显示几乎是顺铂的六倍。此外，没有证据表明P - 糖蛋白（P - gp）介导的多药耐药性（MDR）可能在降低该配合物的抗增殖活性中起作用。细胞学染色、基因组DNA分析以及生化测定（半胱天冬酶 - 3和 - 9以及裂解的聚（ADP - 核糖） - 聚合酶蛋白）表明，细胞死亡可能在凋亡和坏死之间转换，且这种效应似乎具有浓度依赖性。此外，流式细胞术分析表明该配合物通过改变细胞周期进程发挥作用。综上所述，[Cu(cdoa)(phen)₂]已被证明是一种比配体或顺铂更有效的抗增殖剂，并且能够改变导致凋亡和/或坏死性细胞死亡的关键生化事件，表明其值得进一步研究。
