1. Storr Liver Centre, Westmead Institute for Medical Research, University of Sydney and Westmead Hospital, Westmead, NSW 2145, Australia;
2. Department of Molecular and Cell Biology, Centre for Comparative Genomics, The Centre for Biodiscovery and Molecular Development of Therapeutics, James Cook University, Australian Institute of Tropical Health and Medicine, Townsville, QLD 4811, Australia;
3. School of Medicine, Deakin University, Pigdons Road, Waurn Ponds, Victoria 3217, Australia.
Cancer stem cells (CSCs) are believed to be a principal cellular source for tumour progression and therapeutic drug resistance as they are capable of self-renewal and can differentiate into cancer cells. Importantly, CSCs acquire the ability to evade the killing effects of cytotoxic agents through changes at the genetic, epigenetic and micro-environment levels. Therefore, therapeutic strategies targeting CSCs hold great potential as an avenue for cancer treatment. Aptamers or “chemical antibodies” are a group of single-stranded nucleic acid (DNA or RNA) oligonucleotides with distinctive properties such as smaller size, lower toxicity and less immunogenicity compared to conventional antibodies. They have been frequently used to deliver therapeutic payloads to cancer cells and have achieved encouraging anti-tumour effects. This review discusses progress in CSC evolution theory and the role of aptamers to target CSCs for cancer treatment. Challenges of aptamer-mediated CSC targeting approaches are also discussed.
Keywords: aptamers, CSCs, cancer, drug resistance, antibodies, nanoparticles.