Enhancing the anticancer immune response with the assistance of drug repurposing and delivery systems

BACKGROUND: The immune system plays a pivotal role in the initiation, evolution, invasion and metastasis of cancer. Therapeutics aiming at modulating or boosting anticancer immune responses have experienced immense advances during the past decades, for example, anti‐PD‐1/PD‐L1 monoclonal antibodies. MAIN BODY: Concomitant with advancements in the understanding of novel mechanisms of action, conventional or emerging drugs bearing the potential to be repurposed for enhancing anticancer immunity have been identified. Meanwhile, ongoing advances in drug delivery systems enable us to utilise novel therapeutic strategies and impart drugs with fresh modes of action in tumour immunology. CONCLUSION: Herein, we systemically review these kinds of drugs and delivery systems that can unleash the anticancer response through various aspects, including immune recognition, activation, infiltration and tumour killing. We also discuss the current caveats and future directions of these emerging strategies.