Development of BMX siRNA Lipid Nanoparticles using Novel Ionizable, and Cleavable Lipids Discovered through AI and Experimentation for Cancer Therapy

Abstract

Prostate cancer is the most commonly diagnosed male malignancy across the world. It is also considered the fifth leading cause of cancer death in men. in 2020 there was 1,414,249 newly diagnosed cases and 375,000 deaths worldwide from prostate cancer (Leslie SW.2023). The Tec family nonreceptor tyrosine kinase BMX is activated downstream of PI3K and has been implicated in regulation of multiple pathways and in the development of cancers including prostate cancer (Chen S. 2018). The available science supports the role of BMX in advanced prostate cancer, head & neck cancer, aggressive brain cancer, and many other immunological diseases (Cenni, Gutmann et al. 2012). RNA interference plays an important role in regulating the gene expression level within the cells (Agrawal N. 2003). However, delivering small interfering RNA (siRNA is challenging due to many obstacles, such as extremely short half-life in vivo, rapid elimination via glomerular filtration, and inability to cross cell membranes (due to the hydrophilic nature and negative charge of siRNA molecules). In order to use siRNA as a treatment for prostate cancer an effective delivery system is needed. Here, we demonstrate that BMX expression in prostate cancer is suppressed directly by siRNA using the delivery system. The delivery system used is composed of the negatively-charged siRNA encapsulated into a multi-component structure that contains (DOPE), 1,2-Dioleoyl-3 trimethylammonium propane (DOTAP), Cholesterol and Phosphatidylcholine. To further enhance the activity of the BMX siRNA lipid nanoparticle compositions two novel lipids; a cleavable PEGylated lipid, and an ionizable cationic lipid were synthesized and characterized by our team (Abu-Fayyad and Nazzal 2017) and then added to the formulation. The goal of incorporating the novel lipid is to overcome shielding effect PEGylation imparts to the formulation by the presence of PEG2000 in the composition since it represents an obstacle for the formula’s cellular uptake, and the subsequent engulfment by the endosome to release its contents (Kulkarni, Witzigmann et al. 2019).