Brief summary of the stimuli-responsive peptides and their applications
| Stimuli | Peptide Sequence | Therapeutic Strategy | Result | References |
|---|---|---|---|---|
| Enzymes | GPLG↓IAGQ (MMP-2) | Linked protective PEG to CPP-modified liposome via MMP-2-responsive sequence | Enhanced target ability and internalization of nanocarriers in cancer cells | Zhu et al., 2012 |
| PVG↓LIG (MMP-2/9) | Gao et al., 2013 | |||
| GP↓AX (FAP-α) | Ji et al., 2016b | |||
| Acidosis | ACEQNPIYWARYADWLFTTPLLLLDLALLVDADEGTG | Combined pH LIP with a microRNA miR-155 via disulfide bond | Delivery of miR-155 specifically to tumor site and efficient uptake by tumor cells | Andreev et al., 2007 |
| H7 | Conjugated cell-penetrating peptide (R2)2 and H7 modify to polymeric micelle | Activation of cell-penetrating peptide by response of H7 to the acidic tumor microenvironment | Zhao et al., 2016 | |
| E4K4 | Mask to a cell-penetrating peptide via linking by an enzyme-responsive cleavable sequence | Cell-penetrating peptide exposed via E4K4 charge transforming and linker cleaving | Huang et al., 2013a | |
| Hyperthermia | VSSLESKVSSLESKVSKLESKKSKLESKVSKLESKVSSLESK | Leucine zipper peptide-lipid hybrid nanovesicles loaded with Dox inside | Superior serum stability at physiologic temperature and increased drug accumulation in tumor | Al-Ahmady et al., 2012 |
| (VPGVG)40(VPGXG)60 | Temperature triggered activation of the cell penetrating ability of ELP-penta-arginine copolymer | Thermal triggered copolymer assembly increased the local density of arginine and the cell penetrating activity at higher temperature | Macewan and Chilkoti, 2012 | |
| X=A:G; 1:1 |
ELPs, Elastin-like polypeptides; X: any amino acid;↓: cleavable site.