Design and synthesis of dabigatran etexilate derivatives with inhibiting thrombin activity for hepatocellular carcinoma treatment.

Hepatocellular carcinoma (HCC) is one of the most fatal solid malignancies worldwide. Evidence suggests that thrombin stimulates tumor progression via fibrin formation and platelet activation. Meanwhile, we also found a correlation between thrombin and HCC through bioinformatics analysis. Dabigatran is a selective, direct thrombin inhibitor that reversibly binds to thrombin. Dabigatran was used as the lead agent in this study, and 19 dabigatran derivatives were designed and synthesized based on docking mode. The thrombin-inhibitory activity of the derivative AX-2 was slightly better than that of dabigatran. BX-2, a prodrug of AX-2, showed a fairly strong inhibitory effect on thrombin-induced platelet aggregation, and effectively antagonized proliferation of HCC tumor cells induced by thrombin at the cellular level. Furthermore, BX-2 reduced tumor volume, weight, lung metastasis, and secondary tumor occurrence in nude mouse models. BX-2 combined with sorafenib increased sorafenib efficacy. This study lays the foundation for discovering new anti-HCC mechanism based on thrombin. BX-2 can be used as an anti-HCC drug lead for further research.

Synthesis and antineoplastic activity of ethylene glycol phenyl aminoethyl ether derivatives as FOXM1 inhibitors.

FOXM1 signalling pathways are highly expressed in multiple human cancers. Based on the crystal structure of the FOXM1 DNA binding domain, our preliminary research found ethylene glycol (4-benzyloxyphenyl) cyclopentylaminoethyl ether XST20, which could inhibit ovarian cancer cell proliferation and showed a medium affinity for the truncated protein FOXM1. This study intended to develop a FOXM1 inhibitor with stronger affinity and higher efficiency to be utilized as a molecular tool and drug candidate. We evaluated the optimization direction through molecular docking and systematically modified the structure of XST20. A novel class of ethylene glycol phenyl aminoethyl ether derivatives were synthesized, their anticancer activity and mechanism were evaluated, and the structure-activity relationship was summarized. Compound S2 showed a stronger affinity for FOXM1 and improved its activity with a broad-spectrum anticancer effect. S2 displayed selective antiproliferative activity against cancer cells with high expression levels of FOXM1 proteins. S2 should be a good chemobiological tool and a potential leading compound for future studies of anticancer drugs targeting FOXM1.

Structure-based virtual screening towards the discovery of novel FOXM1 inhibitors.

Aim: Given the importance of FOXM1 in the treatment of ovarian cancer, we aimed to identify an excellent specific inhibitor and examined its underlying therapeutic effect. Materials & methods: The binding statistics for FDI-6 with FOXM1 were calculated through computer-aided drug design. We selected XST-119 through virtual screening, performed surface plasmon resonance and in vitro cell antiproliferative activity analysis and evaluated its antitumor efficacy in a mouse model. Results: XST-119 had significantly higher affinity for FOXM1 and antiproliferative activity than FDI-6. XST-119 had a definite inhibitory activity in a xenograft mouse model. Conclusion: We identified XST-119, a FOXM1 inhibitor, with better efficacy for treatment of ovarian cancer. FOXM1 binding sites for small molecules are also highlighted, which may provide the foundation for further drug discovery.