An AND-Gate DNA Nanodevice for Dual Protein-Mediated,Tumor-Specific Imaging

Sensitive and specific imaging of tumor-associated biomarkers offers an effective way for cancer diagnosis.However,most of the reported imaging probes are limited to the targeting of a single biomarker,which may impair imaging precision.Here,we report an aptamer-based,AND-gate DNA nanodevice that relies on the sequential processing of two tumor-associated proteins to produce a specific fluorescent signal for precise tumor imaging.The DNA nanodevice integrates an AS1411 aptamer to bind cell surface nucleolin for tumor targeting and a DNA sensor to respond to intracellular apurinic/apyrimidinic endonuclease 1 for activatable imaging.We evaluated the performance of the system in both living cells and a tumor-bearing mouse model,and demonstrated its capability in tumor cell-specific imaging.We anticipate that this strategy will accelerate the design of multivariate protein-stimulated probes for tumor diagnosis.