Curcumin delivered by solid lipid nanoparticles potentiates radiation effects in MCF7 cancer cells

Curcumin is a natural molecule, extracted from Curcuma longa, with antioxidant, anti-inflammatory and anticancer properties. It can inhibit tumor cells proliferation in vitro [1] and prevent or treat various cancers in vivo [2]. Moreover, it has been recently evaluated for its dose-dependent radiosensitizing and radioprotective activities. Therefore, this molecule could be used in combination with radiotherapy of cancer [3]. Despite the remarkable properties, curcumin efficacy is limited by its low bioavalaibility [4]. To overcome these problem, the delivery by Solid Lipid Nanoparticles (SLN) could represent a promising strategy. In this work we prepared two types of curcumin loaded SLN and tested them on MCF7 breast cancer cells. First we evaluated cell survival by clonogenic assays and both curcumin loaded-SLN resulted more efficacious in cell killing respect to free curcumin. Then, we evaluated combined treatments, testing four X-ray doses alone or in combination with free curcumin or curcumin loaded SLN. The results showed a cell killing enhancing in all the combined treatments in comparison to each type of single treatment and mostly when curcumin was delivered by SLN. In conclusion, curcumin is a promising radiosensitizing molecule and SLN could be good candidate carriers for a preclinical delivery testing in radiobiological studies. 1. Bondì , et al., 2010, Current Nanoscience, 6: 439-445. 2. Chen et al., 2014, Journal of Steroid Biochemistry & Molecular Biology, 143: 11-18. 3. Jagetia, 2007, Advances in Experimental Medicine and Biology, 595: 301-320. 4. Sarika et Nirmala, 2016, Materials Science and Engineering C, 65: 331-337. ?