Near-infrared laser-induced phase-shifted nanoparticles for US/MRI-guided therapy for breast cancer

Abstract

Breast cancer is a refractory malignancy particularly in women, with an accruing morbidity and mortality worldwide. The purpose of this study was to evaluate the efficacy of laser-induced near-infrared (NIR) PFP/Gd-DTPA/ICG@PLGA NPs (PGINPs) in US/MR imaging and regimen for breast cancer; gadolinium-DTPA (Gd-DTPA), perfluoropentane (PFP) and indocyanine green (ICG) were wrapped in the poly (lactic-co-glycolic) acid (PLGA) shell membrane via a double emulsion approach. In this study, under the irradiation of NIR laser, the ICG enriched in the cancerous tissue not only converted optic energy into thermal energy to rapidly heat up the cancer focus but also convert O₂ to singlet oxygen (¹O₂), which can effectively destroy the cancer tissues through photothermal therapy (PTT) and photodynamic therapy (PDT). Meanwhile, the thermal energy thus generated could promote the gasification of PFP to enable visualization of cancer tissues under US imaging. Gd-DTPA in combination with US imaging can also significantly enhance MR imaging to provide US/MR dual-modal imaging. This study proves the efficacy of NIR-inspired multifunctional nano-system PGINPs to potentiate US/MR imaging and regimen for breast cancer.

Keywords: Breast cancer; MR; Near infrared laser; Phase-shifted nanoparticles; Photodynamic therapy; Photothermal therapy; US.