Design of substrate-based BCR-ABL kinase inhibitors using the cyclotide scaffold.
Design of substrate-based BCR-ABL kinase inhibitors using the cyclotide scaffold.
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DOI：
10.1038/srep12974
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发表时间：
2015-08-12
影响因子：
4.6
通讯作者：
Craik DJ
中科院分区：
文献类型：
--
作者：
Huang YH;Henriques ST;Wang CK;Thorstholm L;Daly NL;Kaas Q;Craik DJ
组成型活性酪氨酸激酶BCR-ABL是慢性髓性白血病（CML）的潜在病因。目前的CML治疗依赖于长期使用酪氨酸激酶抑制剂（TKIs），其靶向BCR-ABL的ATP结合位点。在治疗过程中，20-30%的CML患者出现TKI耐药，这通常归因于药物结合区的点突变。我们设计了一类新的肽抑制剂，通过将Abl激酶的最佳底物abtide衍生的序列嫁接到细胞穿透环肽MCoTI-II上，靶向BCR-ABL的底物结合位点。三种接枝的环聚糖在体外低微摩尔范围内显示出显著的Abl激酶抑制作用，使用一种新的激酶抑制试验。我们的工作还表明，在环1和环6中移植肽序列的重组MCoTI-II在体外抑制了[T315I]Abl的活性，这是一种突变的Abl激酶，含有“守门员”突变，以耐多药而闻名。血清稳定性和细胞内化研究的结果证实，MCoTI-II支架提供了铅分子的酶稳定性和细胞穿透特性。综上所述，我们的研究强调，结合ab肽衍生序列的重组环核苷酸是Abl激酶和T315I突变体的有希望的底物竞争抑制剂。
The constitutively active tyrosine kinase BCR-ABL is the underlying cause of chronic myeloid leukemia (CML). Current CML treatments rely on the long-term use of tyrosine kinase inhibitors (TKIs), which target the ATP binding site of BCR-ABL. Over the course of treatment, 20–30% of CML patients develop TKI resistance, which is commonly attributed to point mutations in the drug-binding region. We design a new class of peptide inhibitors that target the substrate-binding site of BCR-ABL by grafting sequences derived from abltide, the optimal substrate of Abl kinase, onto a cell-penetrating cyclotide MCoTI-II. Three grafted cyclotides show significant Abl kinase inhibition in vitro in the low micromolar range using a novel kinase inhibition assay. Our work also demonstrates that a reengineered MCoTI-II with abltide sequences grafted in both loop 1 and 6 inhibits the activity of [T315I]Abl in vitro, a mutant Abl kinase harboring the “gatekeeper” mutation which is notorious for being multidrug resistant. Results from serum stability and cell internalization studies confirm that the MCoTI-II scaffold provides enzymatic stability and cell-penetrating properties to the lead molecules. Taken together, our study highlights that reengineered cyclotides incorporating abltide-derived sequences are promising substrate-competitive inhibitors for Abl kinase and the T315I mutant.