Abstract

Poly (L-lactic acid) (PLA) nanoparticles have the approval of the main institutions for drugs administration and therapeutics. However, the use of lactic acid polymer is controversial because lactic acid has been proposed as an energy source for cancer cells. The aim of this study was to evaluate the cytotoxic, apoptotic and cell cycle properties of PLA and CuSO4-loaded PLA biodegradable nanoparticles on MKN-45 gastric adenocarcinoma cell line. PLA nanoparticles for the delivery of the anticancer active principle CuSO4 were obtained using the double emulsion method. PLA and CuSO4 loaded PLA nanoparticles were morphologically characterized and their size determined using transmission electron microscopy (TEM). The cytotoxicity of this drug delivery system was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; apoptosis was evaluated using YO-PRO-1/Propidium Iodide and cell cycle analysis throughout flow cytometry. CuSO4-loaded PLA nanoparticles were effective inhibitors of MKN45 cancer cell growth. They increased cytotoxicity and apoptosis, and induced G1/Go cell cycle arrest; whereas the anticancer activity was increased using a 96 h treatment of a minimal (1mM) concentration of CuSO4 loaded in 40 mu M PLA nanoparticles. The treatment with 40 mu M lactic acid and PLA (40 mu M) did not increase the rate of cell survival assays related to the control, which indicate that PLA use as a polymer carrier not induce proliferation of MKN-45 cancer cells. Our research presents novel data about the effect of PLA nanoparticles and CuSO4 on gastric cancer cell line MKN45.