Aptamer-Dendrimer Functionalized Magnetic Nano-Octahedrons: Theranostic Drug/Gene Delivery Platform for Near-Infrared/Magnetic Resonance Imaging-Guided Magnetochemotherapy

The combination of magnetic hyperthermia and chemotherapy within a nanosystem is thought to be a promising approach for cancer therapies. However, the nonspecific accumulation and fast clearance of magnetic nanoparticles in the physiological environment limited their further biomedical applications. Herein, we report a highly selective theranostic nanocomplex, ZIPP-Apt:DOX/siHSPs, built with superparamagnetic zinc-doped iron oxide nano-octahedral core, cationic PAMAM dendrimer, and functional surface modifications such as PEG, AS1411 aptamer, and fluorescent tags (FITC or Cy5.5), together with the loading of hydrophobic anticancer drug doxorubicin (DOX) and HSP70/HSP90 siRNAs. Our results demonstrate that the cellular uptake and the tumor-specific accumulation of ZIPP-Apt:DOX/siHSPs were significantly increased due to the AS1411-nucleolin affinity and further confirmed that the simultaneous depletion of HSP70 and HSP90 sensitized magnetic hyperthermia and chemotherapy-induced cell death both in vitro and in vivo. Altogether, our study provides a theranostic nanoplatform for aptamer-targeted, NIR/MR dual-modality imaging guided, and HSP70/HSP90 silencing sensitized magnetochemotherapy, which has the potential to advance versatile magnetic nanosystems toward clinical applications.