Folate-Targeted Nanostructured Lipid Carriers (NLCs) Enhance (Letrozol) Efficacy in MCF-7 Breast Cancer Cells

OBJECTIVE: Targeted-drug-delivery based lipid nanoparticles has emerged as a new and effective approach in cancer chemotherapy. Here, we investigated the ability of folate-modified nanostructured lipid carriers (NLCs) to enhance letrozol (LTZ) efficacy in MCF-7 breast cancer cells. METHODS: New formulations were evaluated regarding to particle size and scanning electron microscope (SEM) features. Anti-proliferative effects of LTZ loaded nanoparticles were examined by MTT assay. To understand molecular mechanisms of apoptosis and cell cycle progression, flow cytometric assays were applied. RESULTS: Optimum size of nanoparticles was obtained in mean average of 98 ± 7 nm with a poly dispersity index (PDI) of 0.165. The IC50 value was achieved for LTZ was 2.2 ± 0.2 µM. Folate-NLC-LTZ increased the percentage of apoptotic cells from 24.6% to 42.2% compared LTZ alone (p<0.05). Furthermore, LTZ loaded folate targeted NLCs caused marked accumulation of cells in the subG1 phase. CONCLUSION: Taken together, our results concluded that folate targeted LTZ can be considered as potential delivery system which may overcome limitations of clinical application of LTZ and improve drug efficacy in tumor tissue.