Nanoencapsulation of an hTS inhibitor octapeptide against ovarian cancer in solid lipid matrix

New octapeptides able to reduce the growth of platinum-resistant cells by inhibiting the enzyme human thymidylate synthase (hTS), cannot cross the cell membrane alone and require an appropriate delivery system. In the aim to transport hTS inhibiting LR octapeptide (LR-op) into the cells, Solid Lipid Nanoparticles (SLNs) were developed and evaluated in vitro. The optimized SLNs were formulated in the absence and presence of squalene (7S and 7Sq) both in the LR-op loaded and unloaded form. All the SLNs produced had dimensions below 150 nm, negative Zpotential and a good stability both in suspension and after freeze-drying. Only the sample obtained in the absence of squalene showed to stably incorporate the LR-op promoting its cell internalization, as demonstrated by in vitro studies on C13* ovarian carcinoma cell line.