[Advances in hydrogel-based delivery of STING agonists for cancer therapy]

The stimulator of interferon genes (STING) pathway plays an important role in innate immunity, and its activation induces immune responses to tumors. However, the clinical translation of STING agonists remains challenging, since the inherent metabolic instability of cyclic dinucleotide (CDN) analog drugs and the systemic toxicity induced by the administration of the new generation of non-CDN agonists. Hydrogels, possessing good biocompatibility and controllable release properties, are widely used in cancer treatment. On the basis of our team's research accumulation in local immunotherapy for malignant pleural effusion (MPE), this review summarizes the application and challenges of hydrogel-based STING agonist delivery systems in cancer therapy. Through local retention and controlled release, such delivery systems enhance tumor-specific immune activation while reducing systemic toxicity. Additionally, we highlight the significant potential of these systems in treating locally intractable conditions such as MPE, providing theoretical insights and technical prospects for their clinical translation.