Development and characterization of liposomal formulations for rapamycin delivery and investigation of their antiproliferative effect on MCF7 cells.

Rapamycin (Sirolimus) is a macrolide lactone with antifungal, immunosuppressant, and antiproliferative actions. The mechanism of rapamycin action involves the inhibition of mTOR and subsequent cytostasis. Rapamycin also prevents angiogenesis in tumors and can prevent cancer cells' resistance to other chemotherapeutic agents.

Tamoxifen citrate loaded amphiphilic beta-cyclodextrin nanoparticles: in vitro characterization and cytotoxicity.

Nanospheres and nanocapsules of beta-CDC6, amphiphilic beta-cyclodextrin modified on the secondary face with 6C aliphatic esters, were prepared with nanoprecipitation technique directly from inclusion complexes of tamoxifen citrate and beta-CDC6 (1:1 molar ratio). Blank and loaded nanospheres and nanocapsules were characterized by particle size distribution, zeta potential, drug loading and in vitro drug release. Particle sizes were between 250 and 300 nm for different formulations of nanospheres and nanocapsules.

Pure antiestrogen RU 58668-loaded nanospheres: morphology, cell activity and toxicity studies.

Nanospheres (NS) formulated using biodegradable and biocompatible polymers, poly(D,L-lactide-co-glycolide) (PLGA), poly(D,L-lactide) (PLA) and poly(epsilon-caprolactone) (PCL), loaded with the pure anti-estrogen RU 58668 (RU), a promising estrogen-dependent anticancer agent, have been prepared. They all possess a small size compatible with an intratumoral extravasation behavior and their pegylation reduce significantly their zeta potential. Characterization by freeze fracture electron microscopy have shown that NS are spheric particles with a size ranging between 30 and 50nm and a tendency to agglomerate which is reduced by polyethylene glycol (PEG) grafting.