This type of inhibitor can selectively up-regulate the expression of the core components of the immunoproteasome (LMP2/PSMB9), optimize the processing efficiency of tumor antigen peptides, and simultaneously increase the expression level of MHC-I/II molecules on the surface of tumor cells, making it easier for cytotoxic T cells to recognize tumor antigens. Here, PSMB9 is linked to neoplasm.