Engineering nanomedicine for STING pathway activation: Advancing cancer immunotherapy

The stimulator of interferon genes (STING) pathway is a fundamental innate immune signaling cascade that, upon activation, potentiates antitumor responses via the secretion of type I interferons and the subsequent promotion of T cell infiltration. Despite their considerable therapeutic potential, the clinical advancement of STING agonists has been hindered by suboptimal pharmacokinetic profiles, off-target activity, and dose-limiting toxicities. Nanomedicine offers a multifaceted strategy to overcome these obstacles by employing programmable carriers that orchestrate the targeted delivery, improving cytosolic internalization, and spatiotemporally controlled release of STING agonists for direct STING pathway priming. Furthermore, nanomedicine can indirectly potentiate STING activation through mechanisms such as induction of DNA damage or release of mitochondrial DNA. The antitumor efficacy of nanomedicine delivered STING agonists can be potentiated through parallel synergistic mechanisms: combination with immune checkpoint inhibitors to reverse T cell exhaustion and pairing with cancer vaccines to amplify tumor-specific immune responses. This review elucidates recent advances in nano-enabled STING activation, highlights ongoing clinical trials, and addresses critical translation challenges. By enabling the spatiotemporally defined orchestration of STING signaling within the tumor microenvironment, nanomedicine address the principal bottlenecks in the clinical translation of STING agonists. These developments provide a strategic framework for broadening the therapeutic window of STING pathway-targeting immunotherapy and for augmenting combination modalities aimed at establishing durable antitumor immune responses.