Construction of Citrostatin and its activity analysis

Objective:To construct a new recombinant antitumor peptide Citrostatin,which consists of 2 anti-tumor domains(by different mechanism),and to study its biological activity,in an effort to search for a peptide with double anti-tumor efficiency.Methods: Citrostatin,a 48-amino acid peptide,was artificially synthesized.After purified by HPLC,Citrostain were subjected to the following tests separately: inhibition of endothelial cell proliferation,MTT test of cytotoxicity,inhibition of endothelial cell tube formation on ECMatrix~(TM),and anti-angiogenesis test in chick chorioallantoic membrane.Results: Citrostatin significantly inhibited the proliferation of human endothelial cell ECV304(ED_(50) =6.2 μg/ml,P0.05). It also significantly inhibited the proliferation of human tumor cells 1990 and NCI-H640(ED_(50)=50 μg/ml,16 μg/ml,both P0.05),and the inhibitory effect became more marked(P0.01) with the increase of Citrostatin concentration.The inhibitory effects of Citrostatin on endothelial cell tube formation and angiogenesis in chick chorioallantoic membrane were also confirmed.Conclusion: An anti-tumor 48-amino acid peptide,Citrostatin,has been successfully synthesized and purified,which shows an anti-angiogenesis effect and a direct cytotoxic effect toward tumor cells.