Gefitinib and curcumin-loaded nanoparticles enhance cell apoptosis in human oral cancer SAS cells in vitro and inhibit SAS cell xenografted tumor in vivo

Curcumin (Cur), a natural product, has been shown to have anti-tumor activities in many human cancer cells. Gefitinib (Gef) is a clinical drug for cancer patients. However, there is no available information to show whether Gef/Cur nanoparticles (NPs) increased cell apoptosis and anti-tumor effects on xenograft mice model in vivo. In this study, gamma-polyglutamic acid-coated nanoparticles loaded with Gef and Cur (gamma-PGA-Gef/Cur NPs) were developed and its physicochemical properties and antitumor effects were investigated in vitro and in vivo. The gamma-PGA-Gef/Cur NPs showed 548.5 +/- 93.7 nm in diameter and -40.3 +/- 3.87 mV on surface charge. The loading efficiencies of Gef and Cur were 89.5 and 100%, respectively. gamma-PGA-Gef/Cur NPs could be internalized into SAS cells and significantly decreased total cell viability of SAS cells. Western blotting results indicated that both free Gef/Cur and gamma-PGA-Gef/Cur NPs induced apoptotic cell death via caspase- and mitochondria-dependent pathways. In vivo studies indicated that treatments of PLGA NPs, free Gef/Cur, and gamma-PGA-Gef/Cur NPs did not significantly affect appearances and bodyweights of mice. But the gamma-PGA-Gef/Cur NPs significantly suppressed tumor size when comparing to free Gef/Cur-treated group. The nanoparticles developed in this study may be used as a potential therapy for oral cancer.