Evaluation of the cytotoxic activity of sorafenib‐loaded camel milk casein nanoparticles against hepatocarcinoma cells

Sorafenib, a multikinase inhibitor is used to treat hepatocellular and renal carcinoma. However, a low solubility impedes its bioavailability and thus, effectiveness. This study aims to enhance its effectiveness by using novel camel milk casein nanoparticles as a delivery system. This study evaluates the cytotoxicity of sorafenib encapsulated in camel milk casein nanoparticles against human hepatocarcinoma cells (HepG2 cells) in vitro. Optimal drug loaded nanoparticles were stable for 1 month, had encapsulation efficiency of 96%, exhibited a particle size of 230 nm, zeta potential of −14.4 and poly disparity index of 0.261. Treatment with it led to cell morphology and DNA fragmentation as a characteristic of apoptosis. Flow cytometry showed G1 phase arrest of cell cycle and 26% increased apoptotic cells population upon treatment as compared to control. Sorafenib‐loaded casein nanoparticles showed 6‐fold increased ROS production in HepG2 cells as compared to 4‐fold increase shown by the free drug. Gene and protein expression studies done by qPCR and western blotting depicted upregulation of tumor suppressor gene p53, pro‐apoptotic Bax, and caspase‐3 along with downregulated anti‐apoptotic Bcl‐2 gene and protein expression which further emphasized death by apoptosis. It is concluded regarding the feasibility of these casein nanoparticles as a delivery system with enhanced therapeutic outcomes against hepatocellular carcinoma cells. Graphical and Lay Summary The present work aims to enhance the bioavailability of sorafenib against hepatocellular carcinoma by using a novel drug delivery system. Sorafenib‐encapsulated camel milk casein nanoparticles showed significant cytotoxicity against HepG2 cells. The treated cells exhibited apoptosis specific morphology, fragmented DNA and ROS‐dependent cell death. Furthermore, apoptotic cell death was confirmed by annexin pi assay and altered expression of apoptotic related genes at a transcription and translational levels. In contrast,encapsulated sorafenib didn't show significant cytotoxicity onHEK293 cells. This study confirms a camel milk casein nanoparticle as a suitable and biocompatible nanoparticulate drug delivery system.