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Abstract Pyroptosis is an immunogenic cell death and would trigger robust antitumor immunity. However, due to cytoxicity of pyroptosis executors, Gasdermin family proteins, it is indispensable to construct tumor‐specific vectors. Here, we report the development of a novel vector named lipid‐coated poly(lactide‐co‐glycolide) (PLGA) nanoparticles coloaded with Gasdermin E expressing plasmid DNA (GSDME‐pDNA) with a heat‐inducible mouse heat shock protein 70 (mHSP70) as the promoter and a photosensitizer indocyanine green (ICG) to activate the mHSP70 element. The cellular internalization and transfection rate of the vector were remarkably enhanced by photothermal treatment. And the mHSP70 promoter further improved the gene transfection rate for about 15‐fold. With the combination of oxaliplatin (OXA), the mechanism switch between apoptosis and pyroptosis was fulfilled by cleavage of GSDME through activated caspase‐3, which promoted damage‐associated molecular patterns (DAMPs) release and increased the infiltration of immune cells at the tumor site. This combination strategy not only prominently inhibited the growth of the treated tumor, but also exhibited a lethal effect on the distal tumors. Besides, mouse colon cancer cell CT26 overexpressing GSDME after OXA treatment had the potential to be the preventive tumor vaccine. This study provides a novel thought and feasible method for the clinical treatment of colon cancer.

Modulation of the cytokine milieu is one approach for vaccine development. However, therapy with pro-inflammatory cytokines, such as IL-12, is limited in practice due to adverse systemic effects. Spatially-restricted gene expression circumvents this problem by enabling localized amplification. Intracellular co-delivery of gold nanorods (AuNR) and a heat shock protein 70 (HSP70) promoter-driven expression vector enables gene expression in response to near infrared (NIR) light. AuNRs absorb the light, convert it into heat and thereby stimulate photothermal expression of the cytokine. As proof-of-concept, human HeLa and murine B16 cancer cells were transfected with a HSP70-Enhanced Green Fluorescent Protein (EGFP) plasmid and polyethylenimine (PEI)-conjugated AuNRs. Exposure to either 42 °C heat-shock or NIR light induced significant expression of the reporter gene. In vivo NIR driven expression of the reporter gene was confirmed at 6 and 24 h in mice bearing B16 melanoma tumors using in vivo imaging and flow-cytometric analysis. Overall, we demonstrate a novel opportunity for site-directed, heat-inducible expression of a gene based upon the NIR-absorbing properties of AuNRs and a HSP70 promoter-driven expression vector.