Nanovaccines for Cancer Prevention and Immunotherapy: An Update Review

Abstract

Cancer immunotherapy has received more and more attention from cancer researchers over the past few decades. Various methods such as cell therapy, immune checkpoint blockers, and cancer vaccines alone or in combination therapies have achieved relatively satisfactory results in cancer therapy. Among these immunotherapy-based methods, cancer vaccines alone have not yet had the necessary efficacy in the clinic. Therefore, nanomaterials have increased the efficacy and ef-fectiveness of cancer vaccines by increasing their half-life and durability, promoting tumor mi-croenvironment (TME) reprogramming, and enhancing their anti-tumor immunity with minimal toxicity. In this review, according to the latest studies, the structure and different types of nanovaccines, the mechanisms of these vaccines in cancer treatment, as well as the advantages and disadvantages of these nanovaccines are discussed.

Keywords: cancer therapy; immunotherapy; nanovaccines.

Figure 1

Nanovaccines in the treatment of cancer. The general structure of nanovaccines, their types, and the mechanism of action of this type of vaccine are shown. After administration of nanovaccine and delivery of antigen and adjuvant to lymphoid tissues, antigens are uptake by DCs, resulting in DCs maturation and activation. After this stage, the matured DCs present the antigens to the CD8⁺ T cells through the MHC molecules and cause T cell expansion. Finally, antigen-specific T cells invade tumor cells in the TME and kill them. APC: antigen-presenting cell; DC: dendritic cell; TAAs: tumor-associated antigens; TLR: Toll-like receptor.

Figure 2

Three main nanocarriers are shown, including biogenic, semi-synthetic and synthetic NCs. NP: nanoparticle; NC: nanocarrier; OMV: outer membrane vesicles; VLP: virus-like particle.

Figure 3

Challenges and limitations of cancer treatment with nanovaccines.