title: Binding capability of the enediyne-associated apoprotein to human tumors and constitution of a ligand oligopeptide-integrated protein.
abstract: The molecule of lidamycin that belongs to the chromoprotein family of antitumor antibiotics is composed of an apoprotein (LDP) and an enediyne chromophore. The enediyne moiety of the molecule is responsible for the potent cytotoxicity; however, the biological function of the apoprotein moiety, particularly its interaction with cancer cells, remains unclear. In present study, the binding capability of LDP to human tumors was detected for the first time by tissue microarray. LDP bound to various human tumors with significant difference from the corresponding normal tissues. Positive correlation between binding activity and the overexpression of VEGF and EGFR was confirmed by lung carcinoma tissue microarray. A fusion protein LG-LDP that consists of LDP and a ligand oligopeptide to EGFR was constructed by DNA recombination. LG-LDP showed augmented binding to EGFR-overexpressing cancer cells. Furthermore, an energized fusion protein LG-LDP-AE was prepared by integrating the active enediyne (AE) into LG-LDP molecule. By MTT assay, LG-LDP-AE displayed extremely potent cytotoxicity to cancer cells with IC50 approximate to 0.01nM. The results indicate that LDP binds to various human tumors and it might serve as a delivery carrier by integration of ligand oligopeptide to manufacture motif-based, targeted fusion proteins for cancer.
authors.affiliation: Department of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Cai
authors.forename: Hongxia
authors.initials: H
authors.lastname: Chen
authors.forename: Qingfang
authors.initials: Q
authors.lastname: Miao
authors.forename: Shuying
authors.initials: S
authors.lastname: Wu
authors.forename: Yue
authors.initials: Y
authors.lastname: Shang
authors.forename: Yongsu
authors.initials: Y
authors.lastname: Zhen
mesh_terms: D020816:Amino Acid Motifs; D000617:Aminoglycosides / Q000378:metabolism* / Q000494:pharmacology; D001059:Apoproteins / Q000737:chemistry / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000473:pathology; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D004705:Endocytosis / Q000187:drug effects; D053281:Enediynes / Q000378:metabolism* / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D008024:Ligands; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D009842:Oligopeptides / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D046888:Tissue Array Analysis; D042461:Vascular Endothelial Growth Factor A
chemical_list: D000617:Aminoglycosides; D001059:Apoproteins; D053281:Enediynes; D008024:Ligands; D009842:Oligopeptides; D011993:Recombinant Fusion Proteins; D042461:Vascular Endothelial Growth Factor A; C058024:C 1027; D066246:ErbB Receptors