Mitochondria-targeting "Nanoheater" for enhanced photothermal/chemo-therapy.

In this work, mitochondria-targeting gold nanostar (AuNS) and anticarcinogen DOX were co-encapsulated in hyaluronic acid (HA) protective shell for tumor-targeting synergistic photothermal/chemo-therapy. Cationic peptide R8 and mitochondria-targeting pro-apoptotic peptide TPP-KLA were co-decorated on AuNS to form AuNS-pep via Au-S bonds. Then, electronegative HA was further coated on the surface via electrostatic interaction for cancer cell targeting. During the coating process, DOX was also introduced via electrostatic interaction to obtain a versatile nanoplatform AuNS-pep/DOX@HA. It was found that the nanoplatform could be internalized into tumor cells via CD44 receptor-mediated recognition. Followed digestion by hyaluronidase (HAase), the therapeutic nanoplatform was able to release DOX for chemotherapy and mitochondria-targeting nanoheater AuNS-pep for near infrared (NIR) light triggered subcellular photothermal therapy (PTT). This tumor-targeting nanoplatform AuNS-pep/DOX@HA displayed prominent non-resistant or resistant tumor inhibition both in vitro and in vivo.