Liposomes in Cancer Therapy: How Did We Start and Where Are We Now

Abstract

Since their first discovery in the 1960s by Alec Bangham, liposomes have been shown to be effective drug delivery systems for treating various cancers. Several liposome-based formulations received approval by the U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA), with many others in clinical trials. Liposomes have several advantages, including improved pharmacokinetic properties of the encapsulated drug, reduced systemic toxicity, extended circulation time, and targeted disposition in tumor sites due to the enhanced permeability and retention (EPR) mechanism. However, it is worth noting that despite their efficacy in treating various cancers, liposomes still have some potential toxicity and lack specific targeting and disposition. This explains, in part, why their translation into the clinic has progressed only incrementally, which poses the need for more research to focus on addressing such translational limitations. This review summarizes the main properties of liposomes, their current status in cancer therapy, and their limitations and challenges to achieving maximal therapeutic efficacy.

Keywords: PEGylation; anticancer therapy; cancer; liposomes; nanoparticle; targeted drug delivery.

Figure 1

Advantages of liposomes as drug delivery systems.

Figure 2

Schematic of liposomes and their different components.

Figure 3

Tumor vasculature leakage. Tumor vasculature exhibits structural abnormalities, fenestrated blood vessels, and absence of a lymphatic system (bottom) compared to normal/healthy vasculature (top). Image was created with BioRender.com (accessed on 1 February 2023).