Markovits J, Linassier C, Fossé P, Couprie J, Pierre J, Jacquemin-Sablon A, Saucier J M, Le Pecq J B, Larsen A K
Laboratoire de Pharmacologie Moléculaire, URA 158 du CNRS, U 140 de l'INSERM, Institut Gustave Roussy, Villejuif, France.
Cancer Res. 1989 Sep 15;49(18):5111-7.
Tyrosine phosphorylation plays a crucial role in cell proliferation and cell transformation which suggests that tyrosine kinase-specific inhibitors might be used as anticancer agents. When the cytotoxic effect of the potent tyrosine kinase inhibitor genistein on various cell lines was studied, we observed that 9-hydroxyellipticine-resistant Chinese hamster lung cells (DC-3F/9-OH-E) were markedly more resistant to genistein than the parental cell line (DC-3F). The DC-3F/9-OH-E cells have been shown to have an altered DNA topoisomerase II activity. We therefore examined the effects of genistein on DNA topoisomerase II-related activities of nuclear extracts from DC-3F cells as well as on purified DNA topoisomerase II from calf thymus. Our results show that genistein (a) inhibits the decatenation activity of DNA topoisomerase II and (b) stimulates DNA topoisomerase II-mediated double strand breaks in pBR322 DNA on sites different from those of 4'-(9-acridinylamino)methanesulfon-m-anisidide, etoposide, and 2-methyl-9-hydroxyellipticinium. Structure-activity studies with six chemically related compounds show that only genistein has an effect on the cleavage activity of DNA topoisomerase II in the concentration range studied. Finally, genistein treatment of DC-3F cells results in the occurrence of protein-linked DNA strand breaks as shown by DNA filter elution. Viscometric (lengthening) studies demonstrate that genistein is not a DNA intercalator. Genistein is therefore an interesting compound because it induces cleavable complexes without intercalation. Taken together, our results show that genistein is an inhibitor of both protein tyrosine kinases and mammalian DNA topoisomerase II. This could be accounted for by the sharing of a common structure sequence between the two proteins at the ATP binding site.
酪氨酸磷酸化在细胞增殖和细胞转化过程中发挥着关键作用，这表明酪氨酸激酶特异性抑制剂可能可用作抗癌药物。当研究强效酪氨酸激酶抑制剂染料木黄酮对各种细胞系的细胞毒性作用时，我们观察到9-羟基玫瑰树碱抗性中国仓鼠肺细胞（DC-3F/9-OH-E）对染料木黄酮的抗性明显高于亲本细胞系（DC-3F）。已证明DC-3F/9-OH-E细胞的DNA拓扑异构酶II活性发生了改变。因此，我们研究了染料木黄酮对DC-3F细胞核提取物中与DNA拓扑异构酶II相关的活性以及对小牛胸腺纯化的DNA拓扑异构酶II的影响。我们的结果表明，染料木黄酮（a）抑制DNA拓扑异构酶II的解连环活性，（b）在与4'-（9-吖啶基氨基）甲磺酰基间茴香胺、依托泊苷和2-甲基-9-羟基玫瑰树碱不同的位点刺激DNA拓扑异构酶II介导的pBR322 DNA双链断裂。对六种化学相关化合物的构效关系研究表明，在所研究的浓度范围内，只有染料木黄酮对DNA拓扑异构酶II的切割活性有影响。最后，如DNA过滤洗脱所示，用染料木黄酮处理DC-3F细胞会导致蛋白质连接的DNA链断裂的发生。粘度测定（延长）研究表明染料木黄酮不是DNA嵌入剂。因此，染料木黄酮是一种有趣的化合物，因为它能诱导可裂解复合物而不发生嵌入。综上所述，我们的结果表明染料木黄酮是蛋白质酪氨酸激酶和哺乳动物DNA拓扑异构酶II的抑制剂。这可能是由于这两种蛋白质在ATP结合位点共享一个共同的结构序列。
