MMP2 and neoplasm: During this ZnP@pyro‐based PDT and PD‐L1 checkpoint blockade combined therapy process, systemic tumor‐specific CTLs responses were generated to directly eradicate primary tumors and completely inhibit untreated distant tumors, and the antitumor immunity was activated to effectively prevent lung metastases in the 4T1 murine model.[127] Over‐expressed MMP‐2 in tumor tissues plays a significant role in the invasion and metastasis.[128] Wang et al. designed a self‐assembly and MMP‐2 responsive nanoplatform to co‐deliver a photosensitizer, IR780, and an anti‐PD‐L1 peptide, APP.