以PLK1 PBD为靶点小分子抑制剂的筛选及抗肿瘤活性研究

Screening of small molecule inhibitors for PLK1 PBD and evaluation of antitumor activities

采用荧光偏振高通量筛选的方法进行PLK1 PBD小分子抑制剂的筛选,对筛选出的阳性化合物F083-0063进行体外抗肿瘤活性研究,以期为寻找抗肿瘤药物提供先导化合物。模型筛选获取一个对PLK1 PBD抑制率较高的化合物F083-0063,其在10μg·mL^(-1)时的抑制率达(99.7±0.4)%;利用软件Graphpad Prism 5计算IC_(50)为1.9±0.1μmol·L^(-1);噻唑蓝比色法(MTT)研究该化合物对不同细胞系增殖的影响,结果显示F083-0063能抑制多种肿瘤细胞系的增殖;流式细胞仪检测发现,其能促进细胞凋亡且能导致细胞G2/M期阻滞;划痕实验测定F083-0063对细胞迁移的影响,结果显示其能抑制He La细胞迁移,在20μmol·L^(-1)时,迁移率低至(37.6±0.7)%。利用分子连接技术探讨化合物与PLK1 PBD结构域的亲和力,发现F083-0063与PLK1 PBD有较好的亲和性;免疫印迹法(Western blotting)检测显示F083-0063可以引发周期相关蛋白表达的增加。综上所述,化合物F083-0063有明显的抗肿瘤活性,并有望成为靶向PLK1 PBD的抗肿瘤先导化合物。

With the method of fluorescence polarization（FP）, we screened small molecule inhibitors for PLK1 PBD to identify the lead compounds for antitumor drugs. FP led to the identification of a potent hit, F083-0063, whose inhibition rate was（99.7 ± 0.4） % at 10 μg·m L-（-1）. The IC_（50） was calculated to be 1.9 ± 0.1 μmol·L-（-1） using Graphpad Prism 5. The effect of the compound on cells＇ multiplication was measured by MTT assay which showed that F083-0063 inhibited the proliferation of many tumor cell lines. Flow cytometry analysis indicated that the F083-0063 promoted cell apoptosis and induced cell G2/M arrest. Migration abilities of cells, evaluated using scratch test, increased significantly in the presence of F083-0063 with the migration rate as low as（37.6 ± 0.7） % at 20 μmol·L-（-1）. Molecular linkage technique found F083-0063 had good affinity with PLK1 PBD. The results of Western blotting showed that the expression of cyclin-dependent proteins was increased after treatment with F083-0063. In summary, F083-0063 has an antitumor activity and is expected to be an antitumor lead compound targeting PLK1 PBD.