Zhu et al. reported a tumor-targeted micellar drug delivery platform prepared by self-assembly of the block copolymers of MMP2-sensitive PEG2000-PTX conjugate, transactivating transcriptional activator peptide-PEG1000-phosphoethanolamine (PE), and PEG1000-PE, acting as MMP2-sensitive functional polymer, cell-penetrating enhancer, and nanocarrier building block, respectively (Zhu et al., 2013). Here, MMP2 is linked to neoplasm.