The dual FAK-HDAC inhibitor MY-1259 displays potent activities in gastric cancers in vitro and in vivo

Epigenetic regulation and Focal adhesion kinase (FAK) are considered to be two important targets for the development of antitumor drugs. Studies have shown that the combination of FAK and HDAC inhibitors could exhibit synergistic effects in a subset of cancer cells in vitro and in vivo. At present, there are few reports on dual target inhibitors of FAK and HDAC. Here, we first reported a new compound MY-1259 as a dual FAK and HDAC6 inhibitor, which exhibited efficient treatment effects on gastric cancers in vitro and in vivo. MY-1259 exhibited potent inhibitory activities against FAK (IC50 = 132 nM) and HDAC6 (IC50 = 16 nM). Notably, MY-1259 showed selective inhibitory potency on HDAC6 over HDAC1, HDAC2 and HDAC3. In addition, MY-1259 could potently inhibit the proliferative activities of MGC-803 and BGC-823 cells (IC50 = 3.91 and 15.46 nM, respectively, using flow cytometry counting), induce cell apoptosis, and cellular senescence. MY-1259 could effectively down-regulate the levels of Ac-Histone H3 and Ac-α-tubulin, and also inhibit the phosphorylation of FAK at three phosphorylation sites Y397, Y576/577 and Y925, thereby inhibiting the activation of ERK and AKT/mTOR. MY-1259 exhibited more effective antitumor effect in vivo than the HDAC inhibitor SAHA and FAK inhibitor TAE-226 alone or in combination, showing the advantages of FAK/HDAC dual inhibitors in the treatment of gastric cancers. Therefore, the results in this work suggested that inhibition of FAK and HDAC by MY-1259 might represent a promising strategy for the treatment of gastric cancers.