Abstract
Apatinib is an oral tyrosine kinase inhibitor that targets VEGFR2 signaling and shows potent antitumor effects in various cancers. In this study, we explored the efficacy of apatinib against oral squamous cell carcinoma (OSCC). The relationships between VEGFR2 protein expression and clinical variables were investigated in OSCC patients. OSCC tissues had higher VEGFR2 levels than paracancerous tissues. Compared to patients with low VEGFR2 expression, patients with high VEGFR2 expression had poorer overall survival (OS) and disease-free survival (DFS). Apatinib significantly induced G0/G1 phase arrest and apoptosis, inhibited cell growth and colony formation ability, and blocked autophagic flux by downregulating p-AKT and p-mTOR signaling via the VEGFR2/AKT/mTOR pathway in vitro. Moreover, the inhibition of ERK phosphorylation increased apatinib-induced apoptosis in vitro and in vivo. Apatinib synergized with SCH772984 to achieve a more significant suppression of tumor growth than individual treatment, suggesting the combination of apatinib and SCH772984 as a potent OSCC therapy.