Curcumin nanoemulsions inhibit oral squamous cell carcinoma cell proliferation by PI3K/Akt/mTOR suppression and miR-199a upregulation: A preliminary study

Background Accumulating evidence indicates that curcumin (CUR) has anticancer properties in various cancers including oral squamous cell carcinoma (OSCC), but CUR is greatly restricted in clinical studies and applications due to its low bioavailability. Interestingly, the bioavailability of CUR was found to be significantly improved using loaded lipid nanoemulsions (NEs). Objectives To investigate the effect of CUR-NEs on cell proliferation of OSCC HSC-3 cells in vitro, and explore the potential mechanism of this effect in a preliminary study. Results CUR-NEs exhibited significantly cytotoxic effects on OSCC cells in a dose-dependent manner, compared with the control. The percentage of cells in proliferative phases (S + G2/M) was gradually decreased in a dose- or time-dependent manner caused by CUR-NEs. Moreover, CUR-NEs downregulated the protein expression of PI3K/Akt/mTOR and upregulated the expression of miR-199a that targeted PI3K in a dose- or time-dependent manner in OSCC cells. Importantly, CUR-NEs cloud effectively counteract the influence on cell proliferation of OSCC cells and the proliferative phases of cell cycle caused by miR-199a inhibitor a time-dependent manner. Conclusions This in vitro preliminary study indicated that CUR-NEs may be an effective therapeutic agent for OSCC. Such effects could be related to inhibition of OSCC cell proliferation by PI3K/Akt/mTOR suppression and miR-199a upregulation.