Sprecher
Beschreibung
MicroRNAs (miRs) control protein expression in cells and some have been found to be deregulated in cells and bodily fluids of cancer patients compared to healthy individuals. Despite their great potential as minimally invasive biomarkers, there is currently no cancer diagnostic test based on circulating miR detection, mainly due to their low endogenous concentration. Prostate cancer (PCa) is the most prevalent cancer in men and novel early-detection strategies could potentially reduce deaths from PCa through earlier diagnosis and more timely intervention. We are using DNA nanotechnology to build membraneless artificial cells, using cholesterol-functionalised DNA nanostars (C-Stars), for multiplexed detection of PCa-associated miRs directly from blood plasma, forgoing the need for cumbersome extraction and PCR amplification methods1. Target miRs can diffuse and interact with specific binding sites within the artificial cell, leading to characteristic reaction-diffusion patterns, which can then be recorded and modelled for quantitative analysis2.
Initial proof-of-concept studies were successfully conducted using DNA equivalent versions of miR-141-3p, which was found to be upregulated in PCa patients. The C-Star artificial cells were introduced into wells containing miR solutions at different concentrations and Z-stack images were taken over time using confocal microscopy. A catalytic hairpin assembly mechanism was also introduced for signal amplification, allowing a detectable signal to be generated from target concentrations as low as 10nM.
Future work will include integration of a multiplexed design to simultaneously detect miR-141-3p and miR-375-3p, as well as further limit of detection improvement. The adjustable miR binding site sequence on the artificial cells also allows this platform to be tailored for any type of cancer that shows an overexpression of specific miRs. This work highlights the potential of DNA nanotechnology to improve accurate diagnosis and monitoring through public screening.
[1] Brady et al. 2017. Nano Lett. 17:3276.
[2] Leathers et al. 2022. JACS. 144:17468.
