Trastuzumab decorated TPGS-g-chitosan nanoparticles for targeted breast cancer therapy

Breast cancer, up-regulated with human epidermal growth factor receptor type-2 (HER-2) has led to the concept of developing HER-2 targeted anticancer therapeutics. Docetaxel-loaded D-α-tocopherol polyethylene glycol 1000 succinate conjugated chitosan (TPGS-g-chitosan) nanoparticles were prepared with or without Trastuzumab decoration. The particle size and entrapment efficiency of conventional, non-targeted as well as targeted nanoparticles were in the range of 126-186 nm and 74-78% respectively. In-vitro studies on SK-BR-3 cells showed that docetaxel-loaded non-targeted and HER-2 receptor targeted TPGS-g-chitosan nanoparticles have enhanced the cellular uptake and cytotoxicity with a promising bioadhesion property, in comparison to conventional formulation i.e., Docel™. The IC₅₀ values of non-targeted and targeted nanoparticles from cytotoxic assay were found to be 43 and 223 folds higher than Docel™. The in-vivo pharmacokinetic study showed 2.33, and 2.82-fold enhancement in relative bioavailability of docetaxel for non-targeted and HER-2 receptor targeted nanoparticles, respectively than Docel™. Further, after i.v administration, non-targeted and targeted nanoparticles achieved 3.48 and 5.94 times prolonged half-life in comparison to Docel™. The area under the curve (AUC), relative bioavailability (F_R) and mean residence time (MRT) were found to be higher for non-targeted and targeted nanoparticles when compared to Docel™. The histopathology studies of non-targeted and targeted nanoparticles showed less toxicity on vital organs such as lungs, liver, and kidney when compared to Docel™.