Expression and purification of human soluble TRAIL in Pichia pastoris and its anti-tumor activity in vitro

Purpose To investigate human soluble TRAIL (sTRAIL) protein expression and purification and its potential anti-tumor activity on hepatocellular carcinoma (HepG2).Methods Soluble TRAIL gene ligated with expression vector pPIC9 was transfected into GS115 (his4) and the recombination strain expressing sTRAIL was screened by MD plate.The effects of different media,methanol inducement period,methanol concentration,and pH were investigated and optimized using shaking flask.The anti-tumor activity of sTRAIL with HepG2 cells was analyzed after purification.Results The highest expression of sTRAIL was obtained at pH 6.0,1% methanol in BMMY medium,with the concentration of (58.7±2.4) mg/L at 48 h.Recombinant sTRAIL protein could induce HepG2 cells apoptosis and inhibit HepG2 cells proliferation effectively.Conclusion The optimized condition of human sTRAIL expression and purification was developed and the obtained recombinant sTRAIL protein may be a promising therapeutic agent for hepatocellular carcinoma.