Murdoch University Research Repository

Welcome to the Murdoch University Research Repository

The Murdoch University Research Repository is an open access digital collection of research
created by Murdoch University staff, researchers and postgraduate students.

Learn more

Development of novel chemically-modified splice-modulating antisense oligonucleotides for tackling Duchenne muscular dystrophy and solid cancers

Le, Bao Tri (2018) Development of novel chemically-modified splice-modulating antisense oligonucleotides for tackling Duchenne muscular dystrophy and solid cancers. PhD thesis, Murdoch University.

PDF - Whole Thesis
Download (79MB) | Preview


Antisense oligonucleotides (AOs) are a class of nucleic acid molecule that can specifically bind to RNA targets and subsequently modulate gene expression by different mechanisms of action. AOs composed of natural nucleotide monomers are not suitable for clinical applications as they are vulnerable to nuclease degradation and possess relatively low target binding affinity. To overcome these impediments, chemically-modified nucleic acid analogues are used to improve AO resistance to nuclease degradation, and target binding affinity. AO-mediated splice modulation has been emerged as a potential treatment approach for different genetic diseases, especially in Duchenne muscular dystrophy (DMD)- an X-linked inherited recessive condition arising from protein-truncating mutations in the dystrophin gene. By blocking the interaction between splicing factors and pre-mRNA, AOs can be used to correct genetic defects by manipulating splicing (exon deletion or inclusion).

This thesis explores the synthesis and screening of various chemically-modified splice-modulating AOs in different cellular models. Chapter 1 provides a broad overview of various nucleic acid therapeutic technologies and the significance of chemically-modified oligonucleotides in drug development. Chapter 2 focused on the evaluation of various chemically-modified nucleotide-modified exon-skipping AOs in DMD. For this purpose, AOs incorporated with various chemically-modified analogues were designed, synthesised and tested their ability to induce exon-23 skipping in mouse dystrophin gene transcript in vitro.

The focus of Chapter 3 was to develop novel splice-modulating AOs targeting Vascular Endothelial Growth Factor (VEGF) towards tackling solid cancers. VEGF is a key regulator in angiogenesis- a process that implicated with cancer development, and in this study we developed novel splice-modulating AOs to inhibit the expression of VEGF and evaluated their efficacy in different cancer cells in vitro.

Overall, the findings in this thesis show promising potential of chemically-modified nucleic acid analogues in developing splice-modulating AOs. The results presented here highlight the scope of chemically-modified splice-modulating AOs towards developing efficient therapeutic molecules in tackling various diseases.

Item Type: Thesis (PhD)
Murdoch Affiliation(s): School of Veterinary and Life Sciences
United Nations SDGs: Goal 3: Good Health and Well-Being
Supervisor(s): Veedu, Rakesh, Wilton, Steve and Fletcher, Sue
Item Control Page Item Control Page


Downloads per month over past year