Photothermally Amplified Therapeutic Liposomes for Effective Combination Treatment of Cancer

Abstract

Near-infrared photothermal therapy has been investigated extensively with regard to selective tumor eradication, yet its clinical translation has been limited because of the absence of FDA-approvable agents with effective phototherapeutic function and minimal systemic toxicity. In this work, we developed photothermally amplified therapeutic liposomes in an attempt to synergize chemotherapy and hyperthermia for effective cancer phototherapy. The anticancer drug cisplatin and the photothermal agent indocyanine green (ICG) were encapsulated in a thermosensitive liposomal formulation at the lipid/ICG ratio maximizing the ICG loading efficiency. These liposomes released cytotoxic cisplatin molecules selectively via ICG-mediated photothermal stimulation. In phototherapeutic studies, these liposomes amplified therapeutic effects both in vitro in cancer cells and in vivo in mouse tumor models significantly over chemotherapy or photothermal therapy alone. We believe that these photothermally amplified therapeutic liposomes composed solely of already FDA-approved components (cisplatin, ICG, and phospholipids) have enormous potential for clinical translation in treating various tumors compatible with laser irradiation.