Analogues of the Allosteric Heat Shock Protein 70 (Hsp70) Inhibitor, MKT-077, As Anti-Cancer Agents
作者:Xiaokai Li、Sharan R. Srinivasan、Jamie Connarn、Atta Ahmad、Zapporah T. Young、Adam M. Kabza、Erik. R. P. Zuiderweg、Duxin Sun、Jason E. Gestwicki
DOI:10.1021/ml400204n
日期:2013.11.14
The rhodacyanine, MKT-077, has antiproliferative activity against cancer cell lines through its ability to inhibit members of the heat shock protein 70 (Hsp70) family of molecular chaperones. However, MKT-077 is rapidly metabolized, which limits its use as either a chemical probe or potential therapeutic. We report the synthesis and characterization of MKT-077 analogues designed for greater stability. The most potent molecules, such as 30 (JG-98), were at least 3-fold more active than MKT-077 against the breast cancer cell lines MDA-MB-231 and MCF-7 (EC50 values of 0.4 +/- 0.03 and 0.7 +/- 0.2 mu M, respectively). The analogues modestly destabilized the chaperone clients, Aka and Raf1, and induced apoptosis in these cells. Further, the microsomal half-life of JG-98 was improved at least 7-fold (t(1/2) = 37 min) compared to MKT-077 (t(1/2) < 5 min). Finally, NMR titration experiments suggested that these analogues bind an allosteric site that is known to accommodate MKT-077. These studies advance MKT-077 analogues as chemical probes for studying Hsp70s roles in cancer.