A multifunctional nanoplatform for ultrasound imaging and autophagy inhibition to enhance photothermal treatment of triple negative breast cancer

Inspired by the fact that therapeutic efficacy for triple negative breast cancer (TNBC) is weaken due to the enhancement of autophagy levels after long-term use of chemotherapeutic agents, a theranostic nanoplatform (CQ@ICG@PFH@PDA-PEG5k) integrating ultrasound (US) imaging and therapeutic functions is rationally designed based on the perfluorohexane (PFH) nanodroplet by loading autophagy inhibitor chloroquine (CQ) and photosensitizer indocyanine green (ICG). After CQ@ICG@PFH@PDA-PEG5k is delivered to tumor regions, CQ and ICG are co-released from the theranostic formulation, followed by liquid-gas phase transition of per-fluorohexane (PFH) upon near-infrared (NIR) laser irradiation, assessing ultrasound (US) imaging function. For seeking a promising alternative for TNBC therapy, the antitumor therapeutic efficacy of CQ@ICG@PFH@PDA-PEG5k is compared with those of ICG@PFH@PDA-PEG5k + free CQ and ICG@PFH@PDA-PEG5k upon photo-thermal therapy (PTT) in vitro and in vivo. The tumor vascularity is investigated by color Doppler flow imaging (CDFI). CQ@ICG@PFH@PDA-PEG5k maybe has great potential for exploitation in TNBC therapy.