SACM - United States of America
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Item Restricted Novel Lipid Polymer Design for Nucleic Acids Delivery(Saudi Digital Library, 2025) Alhazza, Abdulelah; Montazeri, HamidrezaRNA interference (RNAi) is a powerful tool that can selectively downregulate the expression of any protein without the need for expensive and time-consuming drug development processes. Despite the initial excitement and extensive efforts, the potential impact of RNAi in clinical settings has been limited due to challenges in delivering RNA molecules effectively and safely. In parallel, the CRISPR/Cas9 system has revolutionized genome editing by enabling targeted, permanent genetic modifications; however, its success also depends on the development of reliable delivery systems for single-guide RNA (sgRNA)-Cas9 complexes. Lipid nanoparticles (LNPs) have emerged as one of the most successful non-viral carriers for nucleic acids, highlighted by the approval of the first small interfering RNA (siRNA) therapy and the rapid deployment of LNP-based mRNA vaccines against COVID-19. However, achieving efficient and targeted delivery of nucleic acids to solid tumors remains a significant barrier. Polyethyleneimine (PEI), in particular, was once considered the gold standard in polymer-based nucleic acid delivery due to its high transfection efficiency, but its clinical application has been limited by toxicity. In this study, we investigate a novel lipid–polymer nanoparticle (LPNP) platform for the targeted delivery of sgRNA- Cas9 complexes to triple-negative breast cancer (TNBC) cells (MDA-MB-231) and siRNA against Respiratory Syncytial Virus (RSV) viral proteins in human lung cancer A549 cells. We hypothesize that incorporating hydrophobically modified polyethyleneimines (PEIs) into optimized LNP formulations will enhance the delivery of nucleic acids. We first optimized LNP formulations as a benchmark for cellular uptake, cytotoxicity, and silencing efficiency, guided by advanced experimental designs using Design-Expert software. We then systematically replaced the ionizable lipid with specifically engineered cationic polymers, either partially or fully, to generate hybrid LPNPs. Our findings demonstrate that these LPNPs significantly improve nucleic acid delivery to MDA-MB-231 cells. To further confirm the platform’s effectiveness, we tested the best siRNA formulations in A549 cells. Overall, LPNPs showed strong cellular internalization, which translated to silencing efficiency, suggesting that the LPNP systems could be useful in breast cancer and beyond.7 0Item Restricted Development of BMX siRNA Lipid Nanoparticles using Novel Ionizable, and Cleavable Lipids Discovered through AI and Experimentation for Cancer Therapy(Saudi Digital Library, 2025) Alasmari, Abdulaziz Nasser; Abu Fayyad, AhmedProstate 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).7 0Item Restricted Hybrid Cyclic/Linear Peptides in a Multi-Component Lipid Structure as a siRNA Delivery System(Saudi Digital Library, 2020) Alasmari, Abdulaziz Nasser; Montazeri, PharmDelivering siRNA is challenging due to many obstacles, such as extremely short in vivo half-life, rapid elimination via glomerular filtration, and inability to cross cell membranes due to the hydrophilic and negatively-charged nature. Thus, a delivery system is needed to deliver the siRNA into the cells by crossing the negatively-charged phospholipid cell membrane. The goal of this project was to design hybrid cyclic-linear peptides as siRNA delivery system. We designed and synthesized hybrid cyclic-linear peptides [R5K]W5, [R6K]W6, and [R5K]W7 containing positively-charged arginine residues attached to hydrophobic tryptophan chains for more efficient interaction with siRNA and to improve siRNA internalization into the cell. SYBR Green II dye exclusion assay showed a high binding affinity of the peptides with siRNA. The delivery of siRNA into the cells was further enhanced by incorporating hybrid peptides into a multi-component structure called Peptide/Lipid-Associated Nucleic Acids (PLANAs). The efficiency of PLANA for delivery of siRNA to human breast cancer cells was studied by using flow cytometry, exhibiting significantly higher uptake of siRNA with PLANA-containing peptides. The PLANA containing siRNA exhibited protein silencing more efficiently than that of lipofectamine.14 0