Improving the efficacy of antisense oligonucleotides with cationic micelles

Abstract

Short single stranded antisense oligonucleotides (ASOs) are a promising category ofnucleic acid therapies for modulating protein production to alleviate diseases and illnesses. However, ASOs fail to provide their full therapeutic potential due to their lack of cellular uptake. In this thesis, I study and describe my research on the implementation of cationic polymers and micelles to surpass the shortcoming of ASO internalization and delivery. I specifically analyze the difference in polymer architecture between self-assembling cationic micelles and non-self-assembling cationic polymers for ASO complexation and delivery, where it was observed that cationic micelles delivering its ASO payload have a profound improvement in cellular internalization and gene silencing. Additionally, iterations to the cationic micelles formulations were optimized and analyzed. Specifically, the lipophilicity, hydrophilicity, and pH-responsiveness of micelles were probed. It was determined that a higher degree of lipophilicity and a pH-responsive nature towards the core of the micelles can have a compounding effect on the internalization and gene silencing of these ASO possessing complexes. Finally, the cationic micelle vehicle is conjugated with biotin, a well-known targeting group for cancer cells. However, the incorporation of this small molecule targeting group did not come to fruition in the way that we had hoped for by improving the overall cellular uptake or silencing performance. However, it did lay the foundation for incorporating a large amount of biotin into the cationic micelle system. Overall, this thesis facilitated further understanding of the physical and biological characteristics of polymer-mediated ASO delivery.