Preparation of transferrin-modified IR820-loaded liposomes and its effect on photodynamic therapy of breast cancer

Abstract

Abstract Objective To prepare and characterize transferrin (Tf)-modified liposomes (Lipo) encapsulating the photosensitizing agent neoindocyanine green (IR820), and to investigate their effects on breast cancer 4T1 cells as well as in a breast cancer mouse model. Methods Photosensitive liposomes, IR820@Lipo and Tf-IR820@Lipo, were synthesized using thin film dispersion, with encapsulation efficiency assessed via UV detection. The physicochemical properties were analyzed using transmission electron microscopy (TEM) and particle size analysis. Uptake by breast cancer 4T1 cells was evaluated through confocal laser scanning microscopy and flow cytometry, while cell proliferation inhibition was measured using the CCK8 assay. Differences in intracellular fluorescence intensity were utilized to assess drug aggregation in vivo through small animal imaging techniques. The anticancer efficacy and potential side effects of the formulations were examined through pharmacodynamic studies conducted in vivo. Results The mean particle sizes of IR820@Lipo and Tf-IR820@Lipo were found to be 84.30 ± 15.66 nm and 116.20 ± 14.68 nm respectively, with zeta potentials of −8.21 ± 2.06 mV for IR820@Lipo and −5.23 ± 1.19 mV for Tf-IR820@Lipo; TEM revealed that the liposomes exhibited a spheroid morphology with uniform distribution across samples; encapsulation efficiencies reached 86.38 ± 0.99% for IR820@Lipo and an impressive 93.81 ± 1.06% for Tf-IR820@Lipo; notably, Tf-IR820@Lipo significantly inhibited proliferation while promoting apoptosis of the 4T1 cells upon laser irradiation; reactive oxygen species (ROS) detection indicated enhanced fluorescence intensity within the treated cells under light exposure when utilizing both formulations; in vivo experiments demonstrated tumor accumulation of both IR820@Lipo and Tf-IR820@Lipo, indicating effective tumor targeting within a breast cancer mouse model; pharmacodynamic assessments revealed that Tf-IR820@Lipo exhibited superior inhibitory effects against breast cancer without causing liver or kidney dysfunctions in mice nor presenting significant toxic side effects overall. Conclusion Given its high targeting capability, potent efficacy, and low toxicity profile, Tf-IR820@Lipo holds promise as a novel therapeutic agent for breast cancer treatment when combined with photodynamic therapy (PDT), potentially offering new avenues for patient management.

Keywords

• Transferrin photosensitive liposome
• Photodynamic therapy
• Anti-tumor effect
• Breast cancer
• 4T1 cell