Inflammasome-Activating Nanovaccine for Cancer Immunotherapy.

A range of advanced nanovaccines (NV) combined with immunotherapies has recently emerged for treating malignant tumors and has demonstrated promising tumor-suppressive effects. Nevertheless, their effectiveness is often limited by immunosuppression within the tumor microenvironment. To overcome this challenge, new approaches for NV development are required to improve antigen cross-presentation and to remodel the tumor microenvironment. In this issue of Cancer Research, Zhou and colleagues have developed a photo-enhanceable inflammasome-activating nanovaccine (PIN) designed for precise, in situ delivery of a tumor antigen and a hydrophobic small molecule that activates the NLRP3 inflammasome pathway. Near infrared light exposure enables the accumulation of PINs at tumor sites by inducing a photo-triggered charge reversal in the BODIPY-modified PAMAM nanocarrier. Systemic administration of PINs resulted in effective intratumoral activation of the NLRP3 inflammasome and antigen cross-presentation in antigen-presenting cells upon light exposure, leading to enhanced immune responses through increased proinflammatory cytokine production without significant systemic toxicity. Importantly, PINs also enhanced the efficacy of immune checkpoint blockade and promoted the development of long-term immune memory in mouse models of melanoma and hepatocellular carcinoma. Overall, inflammasome-activating NVs represent a cancer immunotherapy strategy by harnessing the innate immune system to achieve robust responses against tumors. Ongoing research and development are crucial to addressing current limitations and advancing this innovative technology toward clinical application. See related article by Zhou et al., p. 3834.