title: Site-specific PEGylation of lidamycin and its antitumor activity.
abstract: In this study, N-terminal site-specific mono-PEGylation of the recombinant lidamycin apoprotein (rLDP) of lidamycin (LDM) was prepared using a polyethyleneglycol (PEG) derivative (M w 20 kDa) through a reactive terminal aldehyde group under weak acidic conditions (pH 5.5). The biochemical properties of mPEG-rLDP-AE, an enediyne-integrated conjugate, were analyzed by SDS-PAGE, RP-HPLC, SEC-HPLC and MALDI-TOF. Meanwhile, in vitro and in vivo antitumor activity of mPEG-rLDP-AE was evaluated by MTT assays and in xenograft model. The results indicated that mPEG-rLDP-AE showed significant antitumor activity both in vitro and in vivo. After PEGylation, mPEG-rLDP still retained the binding capability to the enediyne AE and presented the physicochemical characteristics similar to that of native LDP. It is of interest that the PEGylation did not diminish the antitumor efficacy of LDM, implying the possibility that this derivative may function as a payload to deliver novel tumor-targeted drugs.
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Li
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
authors.forename: Boyang
authors.initials: B
authors.lastname: Shang
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Hu
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
authors.forename: Rongguang
authors.initials: R
authors.lastname: Shao
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
authors.forename: Yongsu
authors.initials: Y
authors.lastname: Zhen
keywords: ADCs, antibody drug conjugates; AE, active enediyne; Anti-TNF Fab′, anti-tumor necrosis factor Fab′; DMSO, dimethyl sulfoxide; Enediyne antibiotic; G-CSF, granulocyte colony stimulating factor; IC50 values, half-inhibitory concentrations; IFN, interferon; IPTG, isopropyl-β-d-thiogalactoside; LB, Luria-Bertani; LDM, lidamycin; Lidamycin; PEG, polyethyleneglycol; Polyethylene glycol; SEC-HPLC, size-exclusion high-performance liquid chromatography; Site-specific PEGylation; mPEG-ALD, methoxy-PEG-propionaldehyde; rLDP, recombinant lidamycin apoprotein; rhG-CSF, recombinant human granulocyte colony stimulating factor