MMP2 and neoplasm: For instance, our group has developed an enzyme‐cleavable self‐delivery NPs (MA‐pepA‐Ce6 NPs) by conjugating acid‐sensitive MET prodrug with photosensitizer (chlorin e6, Ce6) through matrix metalloproteinase‐2 (MMP‐2) cleavable peptide (GPLGVRGDK, pepA).[165] After delivering to tumor site via EPR, MA‐pepA‐Ce6 NPs could be cleaved by overexpressed MMP‐2 to release VRGDK‐Ce6.