A drug repurposing approach of Atorvastatin calcium for its antiproliferative activity for effective treatment of breast cancer: In vitro and in vivo assessment

Breast cancer, the most common cancer among women, caused over 500,000 deaths in 2020. Conventional treatments are expensive and have severe side effects. Drug repurposing is a novel approach aiming to reposition clinically approved non-cancer drugs into newer cancer treatments. Atorvastatin calcium (ATR Ca) which is used for the treatment of hypercholesterolemia has potential to modulate cell growth and apoptosis. The study aimed at utilizing gelucire-based solid lipid nanoparticles (SLNs) and lactoferrin (Lf) as targeting ligand to enhance tumor targeting of atorvastatin calcium for effective management of breast cancer. Lf-decorated-ATR Ca-SLNs showed acceptable particle size and PDI values <200 nm and 0.35 respectively, entrapment efficiency >90% and sustained drug release profile with 78.97 ± 12.3% released after 24 h. In vitro cytotoxicity study on breast cancer cell lines (MCF-7) showed that Lf-decorated-ATR Ca-SLNs obviously improved anti-tumor activity by 2 to 2.5 folds compared to undecorated ATR Ca-SLNs and free drug. Further, In vivo study was also carried out using Ehrlich breast cancer model in mice. Caspase-3 apoptotic marker revealed superior antineoplastic and apoptosis-inducing activity in the groups treated with ATR Ca-SLNs either decorated/ undecorated with Lf in dosage 10 mg/kg/day p < 0.001 with superior activity for lactoferrin-decorated formulation.