Recent advances in siRNA delivery for cancer therapy using smart nanocarriers

Small interfering RNAs (siRNAs) can selectively target and downregulate disease-causing genes, holding great promise in treating human diseases, especially malignant cancers. However, how to efficiently deliver siRNAs into target cell cytosol is a problem that has hindered their clinical application. Here, we review the recent strategies for siRNA delivery on the basis of smart nanocarriers by using stimuli-responsive materials. We highlight the rationales of how to design smart nanocarriers responsive to physiological and external stimuli to improve the delivery efficiency, targeting precision and gene silencing efficacy. Finally, we provide an outlook on the fundamental limitation for clinical translation of siRNA-based nanomedicine that should be overcome by the combination of chemistry, biology, material and medical science.