title: Linkage with cathepsin B-sensitive dipeptide promotes the in vitro and in vivo anticancer activity of PEGylated tumor necrosis factor-alpha (TNF-α) against murine fibrosarcoma.
abstract: To improve the pharmacological profile of tumor necrosis factor alpha (TNF-α), we have synthesized a new PEGylated prodrug, PEG-vcTNF-α, using a cathepsin B-sensitive dipeptide (valine-citrulline, vc) to link branched PEG and TNF-α. PEG-modified TNF-α without the dipeptide linker (PEG-TNF-α) and unconjugated TNF-α were also tested as controls. It was found for the first time that TNF-α released from PEG-vcTNF-α was specifically dependent on the presence of cathepsin B. PEG-vcTNF-α induced higher cytotoxicity and greater apoptosis against L929 murine fibrosarcoma cells than PEG-TNF-α. Reversal of these effects by a cathepsin-B inhibitor confirmed that these effects were mediated by cathepsin B-specific release of TNF-α. In vivo pharmacokinetics studies demonstrated that the plasma stability of PEG-vcTNF-α was significantly increased compared to TNF-α. Finally, the improved anticancer efficacy of PEG-vcTNF-α and the distinct activities among the three formulations confirmed the positive contribution of both PEGylation and the dipeptide linkage to the improved drug-like properties of PEG-vcTNF-α. The results here indicate that linking proteins and PEG via the cathepsin B-sensitive dipeptide may be a promising strategy for developing protein therapeutics.
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
authors.forename: ChuanYun
authors.initials: C
authors.lastname: Dai
authors.forename: Ya
authors.initials: Y
authors.lastname: Fu
authors.forename: Biao
authors.initials: B
authors.lastname: Li
authors.forename: YiGuang
authors.initials: Y
authors.lastname: Wang
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhang
authors.forename: JianCheng
authors.initials: J
authors.lastname: Wang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000378:metabolism / Q000627:therapeutic use*; D002401:Cathepsin B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D045744:Cell Line, Tumor; D004151:Dipeptides / Q000378:metabolism*; D004337:Drug Carriers / Q000378:metabolism; D005260:Female; D005354:Fibrosarcoma / Q000188:drug therapy*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008862:Microsomes, Liver / Q000378:metabolism; D011092:Polyethylene Glycols / Q000378:metabolism / Q000627:therapeutic use*; D011355:Prodrugs / Q000378:metabolism / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D004151:Dipeptides; D004337:Drug Carriers; C092033:PEG-modified tumor necrosis factor-alpha; D011355:Prodrugs; D014409:Tumor Necrosis Factor-alpha; D011092:Polyethylene Glycols; D002401:Cathepsin B