New "Trojan horse" discovered to treat cancer

Inspired by Greek mythology, scientists have discovered a novel way to attack cancer cells resistant to chemotherapy, by hiding drugs inside folded-up DNA like the `Trojan Horse`. DNA origami involves folding a single strand of DNA into a complex pattern, creating a 3D structure. In their study, Baoquan Ding at the National Center for Nanoscience and Technology in Beijing, China, and colleagues loaded a tubular piece of folded DNA with doxorubicin, a chemotherapy drug. The DNA Trojan horse delivered a dose of the drug that proved lethal to human breast-cancer cells, even though they had developed resistance to doxorubicin. "This is the first study to demonstrate that DNA origami can be used to circumvent drug resistance," New Scientist quoted Hao Yan at Arizona State University in Tempe, who jointly led the work, as saying. In doing so, Yan explained, cancer cells might not recognise the DNA origami as a threat in the way that free doxorubicin is. The folded DNA might also alter the pH inside the cells, increasing the drug`s activity. Although a multitude of promising anti-cancer drugs have been developed over the past 50 years, effective delivery of the drugs to diseased cells remains a challenge, scientists said in the `Journal of American Chemical Society`. Recently, nanoparticles have been used as drug delivery vehicles due to their high delivery efficiencies and the possibility to circumvent cellular drug resistance. However, the lack of biocompatibility and inability to engineer spatially addressable surfaces for multi-functional activity remains an obstacle to their widespread use. The present discovery presents a novel drug carrier system based on self-assembled, spatially addressable DNA origami nanostructures that confronts these limitations. The new method is inspired by the `Trojan Horse` that allowed the Greeks to finally enter the city of Troy and end the conflict. PTI