Using the DNA origami technique, we constructed a DNA nanodevice functionalized with small interfering RNA (siRNA) within its inner cavity and the chemotherapeutic drug doxorubicin (DOX), intercalated in the DNA duplexes. The incorporation of disulfide bonds allows the triggered mechanical opening and release of siRNA in response to intracellular glutathione (GSH) in tumors to knockdown genes key to cancer progression. Combining RNA interference and chemotherapy, the nanodevice induced potent cytotoxicity and tumor growth inhibition, without observable systematic toxicity. Given its autonomous behavior, exceptional designability, potent antitumor activity and marked biocompatibility, this DNA nanodevice represents a promising strategy for precise drug design for cancer therapy.

The CRISPR/Cas9 gene-editing system has become a promising strategy for tumor therapy with its powerful oncogene-editing ability. However, the efficient delivery of sgRNA/Cas9 complex into target tumor cells remains a challenge. Herein, we report a facile strategy for the construction of an sgRNA/ Cas9 complex co-assembled nanoplatform for targeted gene editing and combined tumor therapy. In our design, the TAT peptide and thiolated DNA linker functionalized gold nanorod can efficiently load the sgRNA/Cas9 complex through the hybridization between the 3′ overhang of sgRNA and the DNA linker. Due to the integration of an active cell targeting group (aptamer) and nuclear targeting peptide (TAT), the multifunctional nanoplatform can elicit the targeted cellular internalization and efficient nuclear targeting transportation to realize endogenous RNase H activated gene editing of the tumor-associated gene polo-like kinase 1 (PLK1). With mild photothermal treatment, this sgRNA/Cas9 complex loaded nanoplatform achieved efficient inhibition of tumor cell proliferation. This multifunctional nanocarrier provides a new strategy for the development of combined tumor therapy.

The more than three decades of research in nucleic acid nanotechnology has led to the thrilling progress in rationally designed structures and artificial molecular devices with programmable functions and various applications. Nucleic acid–based aggregates feature precise molecular recognition and sequence programmability, versatility, as well as marked biocompatibility, providing promising candidates for biomedical applications. In this minireview, we summarize the recent, successful efforts to construct and employ nucleic acid–based aggregates for biomedical applications, including drug delivery, bioimaging, biosensing, cell analysis, and combined cancer therapy. We also discuss the remaining challenges and opportunities in the field.