Hybrid cell membranes camouflage liposomes containing payloads to improve breast cancer chemo and photodynamic therapy.

The treatment of unresectable locally advanced triple-negative breast cancer (TNBC) and TNBC with metastasis is challenging. Many anticancer drugs, such as doxorubicin, still hinder positive therapeutic outcomes due to severe side effects. Photodynamic therapy (PDT) has an anticancer effect, and combining PDT with chemotherapy may improve breast cancer therapy. The use of cargo-loaded biomimetic PEGylated liposomes for cancer therapy may enhance efficacy and reduce side effects. In this study, liposomes were formulated to accommodate doxorubicin (Dox) and IR780. Breast cancer cells (4T1 cells) and macrophage cell membranes were isolated and camouflaged onto the PEGylated liposomes, creating a new biomimetic platform called Dox-IR780@Lip@Ms. The Dox-IR780@Lip@Ms platform was characterized and tested in vitro and in vivo. The results showed that the Dox-IR780@Lip@Ms had an ovoid shape with a double lamina structure, monodispersity, and uniform distribution. The size was 132.37 ± 1.22 nm, the PDI was 0.044 ± 0.067, and the zeta potential was -9.67 ± 1.08 mV. The encapsulation efficiency of Dox and IR780 in Dox-IR780@Lip@Ms was 89.36% ± 3.07% and 92.34% ± 0.66%, respectively. The release rate of Dox from Dox-IR780@Lip@Ms was good after laser irradiation. At pH 7.4, the release rate of Dox was 23.85% ± 0.62% at 3 h without laser irradiation and 36.62% ± 1.32% at 3.5 h with laser irradiation. At pH 6.5, the release rate of Dox was 32.54% ± 0.32% at 3 h without laser irradiation and 62.79% ± 2.15% at 3.5 h with laser irradiation. The cytotoxicity of IR780@Lip@Ms was lower than that of Dox-IR780@Lip@Ms. The cell uptake and generation of reactive oxygen species of Dox-IR780@Lip@Ms were significant. Dox-IR780@Lip@Ms exhibited immune escaping ability in vitro, homotypic targeting ability to cancer cells, high capability to kill cancer cells after laser irradiation, minimal cardiotoxicity, increased accumulation of Dox and IR780 in the tumor, and an increased anticancer effect in a tumor-bearing animal model. In conclusion, hybrid cell membranes of breast cancer and macrophages camouflaging PEGylated liposomes loaded with Dox and IR780 can significantly improve breast cancer therapy after laser irradiation in murine models.