Background: Triple-negative breast cancer (TNBC) is a kind of aggressive breast cancer with a high rate of metastasis, poor overall survival time, and a low response to targeted therapies. To improve the therapeutic efficacy and overcome the drug resistance of TNBC treatments, here we developed the cancer cell membrane-coated oxygen delivery nanoprobe, CCm-HSA-ICG-PFTBA, which can improve the hypoxia at tumor sites and enhance the therapeutic efficacy of the photodynamic therapy (PDT), resulting in relieving the tumor growth in TNBC xenografts.
Results: The size of the CCm-HSA-ICG-PFTBA was 131.3 ± 1.08 nm. The in vitro 1O2 and ROS concentrations of the CCm-HSA-ICG-PFTBA group were both significantly higher than those of the other groups (P < 0.001). In vivo fluorescence imaging revealed that the best time window was at 24 h post-injection of the CCm-HSA-ICG-PFTBA. Both in vivo 18F-FMISO PET imaging and ex vivo immunofluorescence staining results exhibited that the tumor hypoxia was significantly improved at 24 h post-injection of the CCm-HSA-ICG-PFTBA. For in vivo PDT treatment, the tumor volume and weight of the CCm-HSA-ICG-PFTBA with NIR group were both the smallest among all the groups and significantly decreased compared to the untreated group (P < 0.01). No obvious biotoxicity was observed by the injection of CCm-HSA-ICG-PFTBA till 14 days.
Conclusions: By using the high oxygen solubility of perfluorocarbon (PFC) and the homologous targeting ability of cancer cell membranes, CCm-HSA-ICG-PFTBA can target tumor tissues, mitigate the hypoxia of the tumor microenvironment, and enhance the PDT efficacy in TNBC xenografts. Furthermore, the HSA, ICG, and PFC are all FDA-approved materials, which render the nanoparticles highly biocompatible and enhance the potential for clinical translation in the treatment of TNBC patients.
Keywords: Cancer cell membranes; Hypoxia; Nanoprobes; Oxygen delivery; Photodynamic therapy; Triple-negative breast cancer.