dc.description.abstract | Metformin has recently received attention for its potential effects with respect to cancer prevention and treatment. Nonetheless, the low bioavailability and short half-life of metformin hamper its application as an anti-cancer drug. The present study aims to evaluate the efficiency of PLGA-PEG as a nanocarrier for metformin to enhance anticancer effects. For this purpose, metformin-loaded PLGA-PEG NPs were synthetized and characterized using DLS, FE-SEM and FTIR. Then, the inhibitory effects of free and nano-encapsulated forms of metformin on growth and expression levels of hTERT in two breast cancer cell lines, T47D and MDA-MB-231, were evaluated using MTT and qPCR assays, respectively. Assessment of drug toxicity revealed that metformin-loaded NPs had more cytotoxic effects than free form in both cell lines at a dose-and time-dependent manner. The IC50s of free and nanoformulated metformin for MDA-MB-231 cells were lower than T47D cells, indicating the higher sensitivity of the triple-negative phenotype. Also, it was found that nanoformulated metformin than free metformin could further decline the expression levels of hTERT in both cell lines, especially MDA-MB-231 (p < 0.05). It is speculated that nano-encapsulation of metformin into polymeric NPs may be a promising and convenient approach to improve its efficiency in breast cancer therapy. (c) 2017 Elsevier B.V. All rights reserved. | |