A liquid biopsy-guided drug release system for cancer theranostics: integrating rapid circulating tumor cell detection and precision tumor therapy.

Theranostics combining precision diagnosis and concurrent therapy has attracted significant attention as a promising strategy against life-threatening cancer. Liquid biopsy provides a real-time assessment of cancer by the analysis of tumor biomarkers, among which circulating tumor cells (CTCs) have been widely used to monitor disease progression and therapeutic response. In this study, a liquid biopsy-guided drug release system (LBDR system) integrating cancer diagnostic and therapeutic functions on a magnetically controlled microfluidic platform is presented. Two kinds of magnetic nanospheres (MNs), recognition MNs and drug-loaded MNs, are loaded onto the microfluidic chip to integrate the rapid detection of CTCs and controlled drug release. When CTCs bind to aptamers on the recognition MNs, complementary strands (cDNAs) hybridized with the aptamers are released and then conjugated with drug-loaded MNs to further trigger the release of anti-cancer drugs. The amount of drug released is controlled according to the number of detected CTCs, which can provide effective treatment for individual patients according to the diagnostic results. This LBDR system provides a novel strategy for cancer therapy and may facilitate the development of personalized cancer therapy.