Antisense and siRNA oligonucleotides offer the promise of highly precise manipulation of genes involved in disease pathogenesis. However, despite the investment of enormous resources, that promise has been fulfilled to only a limited degree. A key impediment to oligonucleotide-based therapeutics is the difficulty in delivering these large, highly polar molecules to their sites of action in the cytosol or nucleus of tissue cells. While chemical modification of oligonucleotides and the utilization of various nanotechnology-based delivery approaches have been helpful, the delivery problem remains challenging. Much of the oligonucleotide accumulated by cells remains non-productively entrapped in endosomes. The complex pathways of endocytosis and intracellular trafficking are being increasingly understood at the molecular level; however, there is a paucity of small molecule probes for these pathways. Here we describe a novel technology based on the use of small organic molecules to enhance the functional delivery and pharmacological effectiveness of oligonucleotides by manipulating their intracellular trafficking. We have established a proof of principle for this strategy by identifying compounds using a high throughout screen of >100,000 small molecules. Three distinct compound series were discovered from this screen that significantly enhance oligonucleotide effects in cell culture, and in one case in a transgenic mouse model. We now propose medicinal chemistry efforts to build structure activity relationships and improve both potency and pharmacological properties with the end goal of creating molecules that can effectively and safely be used in vivo. Promising leads will be examined for their pharmacokinetic and biodistribution behavior. Finally, these leads will be evaluated in a xenograft tumor model. The identification of potent and non-toxic enhancing molecules will likely have a major impact on the entire field of oligonucleotide therapeutics.
A key impediment to oligonucleotide-based therapeutics is the difficulty in delivering these large, highly polar molecules to their sites of action in the cyosol or nucleus of tissue cells. While chemical modification of oligonucleotides and the utilization of various nanotechnology-based delivery approaches have been helpful, the delivery problem remains largely unresolved. We have taken an orthogonal approach to this problem and have developed small molecule compounds that enhance the functional delivery and pharmacological effectiveness of oligonucleotides by manipulating their intracellular trafficking. Here we propose to optimize compounds as in vivo probes; it seems likely that this effort will have a major impact on the entire field of oligonucleotide therapeutics.
| Wang, Ling; Ariyarathna, Yamuna; Ming, Xin et al. (2017) A Novel Family of Small Molecules that Enhance the Intracellular Delivery and Pharmacological Effectiveness of Antisense and Splice Switching Oligonucleotides. ACS Chem Biol 12:1999-2007 |
| Yang, Bing; Ming, Xin; Abdelkafi, Hajer et al. (2016) Retro-1 Analogues Differentially Affect Oligonucleotide Delivery and Toxin Trafficking. ChemMedChem 11:2506-2510 |
