Design of Nanostructure Materials to Modulate Immunosuppressive Tumour Microenvironments and Enhance Cancer Immunotherapy

Cancer immunotherapy uses host’s inherent immune system to treat cancer and imparts a memory effect on the immune system that can inhibit cancer relapse. However, due to the complexity and diversity of the immune context of the tumour microenvironments (TMEs), tumour cells form their own immune mechanisms to interact with TMEs, and they usually escape from cancer immunotherapy using it. The TMEs that down-regulate the therapeutic effects contains (1) immune suppressive cells (myeloid-derived suppression cells (MDSCs), tumour-associated macrophages (TAMs), and regulatory T cells (Treg)), (2) cytokines and chemokines (inflammatory(anti-tumoural) cytokines; TNF-α, IL-12, IL-6, IFN-γ, anti-inflammatory (pro-tumoural) cytokines; IL-10, TGF-β, angiogenic cytokine; VEGF, cell-promoting cytokines/chemokines; CCL22 and GM-CSF), and (3) enzymes controlling TMEs-related cell metabolism (IDO, arginase, and NOS2). These immune-suppressive factors have remained as an essential target for elaborating the therapeutic responsive rates. In these days, nanotechnology-based approach was suggested as a novel strategy to revert pro-tumoral TMEs to antitumoral immune niches. In this chapter, we will review on the progress of engineered nanostructured materials that were developed to enhance the therapeutic efficacy of cancer immunotherapy by modulating such immune suppressive factors in TMEs.