New opportunities for nanoparticles in cancer immunotherapy

Abstract

BackgroundRecently, cancer immunotherapy has become standard for cancer treatment. Immunotherapy not only treats primary tumors, but also prevents metastasis and recurrence, representing a major advantage over conventional cancer treatments. However, existing cancer immunotherapies have limited clinical benefits because cancer antigens are often not effectively delivered to immune cells. Furthermore, unlike lymphoma, solid tumors evade anti-cancer immunity by forming an immune-suppressive tumor microenvironment (TME). One approach for overcoming these limitations of cancer immunotherapy involves nanoparticles based on biomaterials.Main bodyHere, we review in detail recent trends in the use of nanoparticles in cancer immunotherapy. First, to illustrate the unmet needs for nanoparticles in this field, we describe the mechanisms underlying cancer immunotherapy. We then explain the role of nanoparticles in the delivery of cancer antigens and adjuvants. Next, we discuss how nanoparticles can be helpful within the immune-suppressive TME. Finally, we summarize current and future uses of nanoparticles with image-guided interventional techniques in cancer immunotherapy.ConclusionRecently developed approaches for using nanoparticles in cancer immunotherapy have enormous potential for improving cancer treatment. Cancer immunotherapy based on nanoparticles is anticipated not only to overcome the limitations of existing immunotherapy, but also to generate synergistic effects via cooperation between nanoparticles and immune cells.

Materials for Immunotherapy

“…At its most basic level, nanoparticles have high surface areas and are amenable to modifications for multiplexed effects . The base materials can double as contrast enhancers or imaging probes (e.g., for magnetic resonance imaging (MRI), near infrared (NIR), X‐ray, ultrasound, or Raman), enabling theranostic capabilities . The utility of immunotherapies can be enhanced by the use of materials that are sensitive to photothermia and magnetic hyperthermia (e.g., for ablating tissues and generating free antigens as a primer for vaccination) .…”

Immunotherapy: A Challenge of Breast Cancer Treatment

“…Results obtained with nanoparticles are no less important, having been postulated as the great asset to overcome the limitations of existing immunotherapy, being able to improve overall anti-cancer immune responses with minimal systemic side effects [107]. However, although nanoparticles in different in vitro and in vivo breast cancer models [108] have already proven their efficacy in defeating the immune-suppressive effect of tumor microenvironment [107] and drug resistance [108], as well as in delivering neoantigens and adjuvants to tumor cells [107], reducing the side effects of anticancer drugs [109], certain nanoparticles like titanium dioxide, silica, and gold complexes can lead to the formation of micrometer-size gaps in the blood vessel's endothelial walls and the intravasation of surviving cancer cells into the surrounding vasculature, which increases the risk of metastasis [110].…”

The solid progress of nanomedicine

“…In addition, nanotechnology-enabled cancer therapies do not merely focus on placing drugs at the tumor site, but also seek to provide novel therapeutic approaches in line with the discovery of new disease mechanisms and the precision oncology concept, and to restrict the interplay with other non-tumor cells involved in tumor progression and dissemination [17,18]. Hence, an improved understanding of the disease mechanisms will enable the development of more efficient nanomedicines with mechanisms of action beyond tumor nanoparticle accumulation [19,20]. For instance, nanoparticles are currently being explored in the fields of adoptive cell therapy and immune modulation in various stages of preclinical and clinical development [21].…”