State-of-the-art review on liposomes as versatile cancer vaccine delivery systems

Cancer vaccines represent a growing field of immunotherapy, aiming to harness the body's immune system to combat malignant diseases. Liposomes, as versatile nanocarriers, offer significant advantages for delivering cancer vaccines. This review first delves into the cardinal role of dendritic cells in antitumor immunity and then explores how liposomes can effectively encapsulate and deliver various antigens, such as proteins, peptides, nucleic acids, and tumor lysates, to enhance dendritic cell maturation. By incorporating adjuvants and employing targeted delivery strategies, liposomal vaccines can stimulate both humoral and cellular immune responses, including CD4+ and CD8+ T cells. Liposomes can also be functionalized for targeted delivery to dendritic cells and CD169+ macrophages using specific targeting moieties. The potential of combining liposomal vaccines with immune checkpoint blockers to overcome immune evasion is also discussed, along with emerging delivery routes such as intranasal, oral, inhalation, and implantable vaccines. This article concludes by emphasizing the promising yet developing clinical potential of liposomal vaccines while acknowledging that further research is needed to optimize liposomal vaccine formulations, address stability issues, and improve the consistency and durability of antitumor responses.