Here, we synthesized a tumor microenvironment-sensitive delivery polymer by conjugating HA to cationic PEI along with an MMP-2-sensitive peptide (P; GPLGLAGC) (Han et al., 2017) linker (HA-P-PEI) to deliver the PD-L1–siRNA into H1975 cells. Here, CD274 is linked to neoplasm.