CD274 and neoplasm: Finally, acid-sensitive nanoscale coordination polymer particles (NCPs), formed from zinc ions (Zn2+) and phosphate groups, co-deliver a carboplatin prodrug, PD-L1-targeting siRNA, and digitoxin, triggering apoptosis, enhancing immunogenicity, and downregulating PD-L1 to reactivate antitumor immune responses and suppress tumor progression and metastasis [43].