A Novel Aurora-A Inhibitor (MLN8237) Synergistically Enhances the Antitumor Activity of Sorafenib in Hepatocellular Carcinoma

Currently, sorafenib-based therapy is the standard treatment for advanced hepatocellular carcinoma (HCC), and there is a strong rationale for investigating its use in combination with other agents to achieve better therapeutic effects. Aurora-A, a member of a family of mitotic serine/threonine kinases, is frequently overexpressed in human cancers and therefore represents a target for therapy. Here, we investigated a novel Aurora-A inhibitor, MLN8237, together with sorafenib in HCC cells in vitro and in vivo, and elucidated the possible molecular mechanism. Here, it was found that MLN8237 was strongly synergistic with sorafenib in inhibition of HCC progression by altering cell growth, cell-cycle regulation, apoptosis, migration, invasion, and angiogenesis. Mechanism dissection suggests that the combination of MLN8237 and sorafenib led to significant inhibition of the activation of phospho-Akt (p-Akt) and phospho-p38 mitogen-activated protein kinase (p-p38 MAPK) and their downstream genes including CDK4, cyclinD1, and VEGFA. The activators of p-Akt and p-p38 MAPK signaling partially reversed the synergistic inhibitory effects of sorafenib and MLN8237 on HCC progression. Subsequent in vivo studies further confirmed the synergistic effects of sorafenib and MLN8237. Collectively, the newly developed sorafenib-MLN8237 combination may be a novel therapy to better inhibit HCC progression.