Reversal of the immunosuppressive tumor microenvironment by nanoparticle-based activation of immune-associated cells.

Immunotherapy that activates the host immune system to reverse immunosuppression has emerged as a new generation of cancer treatment in both preclinical studies and clinical trials. Although immunotherapy has shown significant achievements in the treatment of various cancers, it faces challenges that limit its further evolution such as poor permeation and modest responsiveness. The development of nanoparticle drug delivery system has provided an opportunity to overcome these drawbacks and to achieve optimized immunotherapy. Based on the research of our group, we here introduce the new strategies being employed using nanoscale intelligent drug delivery systems to enhance the effects of cancer immunotherapy. We also provide a perspective on the further possible application of nanoparticles in more effective antitumor immunotherapy.