title: Recombinant snake venom cystatin inhibits the growth, invasion and metastasis of B16F10 cells and MHCC97H cells in vitro and in vivo.
abstract: Studies have shown that expression of snake venom cystatin (sv-cystatin) in mouse melanoma cells and human gastric carcinoma cells can inhibit their invasion and metastasis. To advance the research into the biological features and pharmaceutical applications of sv-cystatin, we investigated the expression of recombinant sv-cystatin in an optimized Pichia pastoris system. Approximately 5 mg/L of bioactive sv-cystatin was obtained with a purity of 95.08%. Kinetic analyses of recombinant sv-cystatin revealed highly effective inhibitory efficiency against papain (Ki = 2.67 nM). We further investigated the effects of recombinant sv-cystatin on the invasion and metastasis of B16F10 cells and MHCC97H cells in vitro and in vivo. Matrigel invasion assays showed significant inhibition of recombinant sv-cystatin on the tumor cells in vitro. For experimental lung colonization assays, C57BL/6 mice inoculated in the lateral tail vein with B16F10 cells were treated with three i.v. injections of recombinant sv-cystatin (25 and 50 mg/kg) 24 h before cell inoculation, and 2 h and 24 h after cell inoculation. Administration of recombinant sv-cystatin significantly suppressed the formation of lung tumor colonies. For spontaneous metastasis assays, MHCC97H cells were inoculated s.c. into nude mice. After 24 h, recombinant sv-cystatin was administered by i.p. injections at 25, 50 or 100 mg/kg once daily for 5 days. Administration of recombinant sv-cystatin significantly decreased the formation of lung tumor colonies. Taken together, recombinant sv-cystatin inhibits the invasion and metastasis of tumor cells in vitro and in vivo. These results may facilitate the future evaluation of the pharmaceutical applications of sv-cystatin.
authors.affiliation: Key laboratory of Ministry of Education for Gastrointestinal Cancer, Research Center of Molecular Medicine, Fujian Medical University, Fuzhou 350004, PR China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Xie
authors.forename: Nanhong
authors.initials: N
authors.lastname: Tang
authors.forename: Rong
authors.initials: R
authors.lastname: Wan
authors.forename: Yuanlin
authors.initials: Y
authors.lastname: Qi
authors.forename: Xu
authors.initials: X
authors.lastname: Lin
authors.forename: Jianyin
authors.initials: J
authors.lastname: Lin
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003094:Collagen; D015891:Cystatins / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D004338:Drug Combinations; D004546:Elapid Venoms / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D015151:Immunoblotting; D007700:Kinetics; D007797:Laminin; D051379:Mice; D008810:Mice, Inbred C57BL; D009361:Neoplasm Invasiveness / Q000517:prevention & control*; D009362:Neoplasm Metastasis / Q000517:prevention & control*; D010206:Papain / Q000037:antagonists & inhibitors; D010843:Pichia; D011509:Proteoglycans; D011994:Recombinant Proteins / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D015891:Cystatins; D004338:Drug Combinations; D004546:Elapid Venoms; D007797:Laminin; D011509:Proteoglycans; D011994:Recombinant Proteins; C059485:matrigel; D003094:Collagen; D010206:Papain