STING1 and neoplasm: In this work, we report a TME-activatable nanoassembly based on natural-occurring bovine serum albumin (BSA) and ferritin for spatiotemporally coordinated Mn2+ delivery to tumor-residing DCs and immunogenic apoptosis induction in tumor cells by exploiting the cGAS-STING stimulatory function of Mn2+ ions, which leads to cooperative cGAS-STING activation in DCs to elicit robust T cell-mediated antitumor immunity.