Polypeptide for the treatment of cancer and a method for preparation thereof

摘要

This invention characterizes the specific peptide fragment derived from specially prepared zinc charged fetuin and a method of preparation thereof, wherein the fragment was found to contain an apoptosis-inducing activity. Specifically, the amino acid sequence of this peptide is His-Thr-Phe-Met-Gy-Val-Val-Ser-Leu-Gly (SEQ ID NO: 3) and correlates to amino acid no. 300-309 of bovine fetuin, referred to herein as Fetuin Peptide Fragment (FPF 300-09). FPF 300-09 strongly induced apoptosis in LNCaP (prostate cancer) and HT-29 (colon cancer) cells without affecting CCD 18 Co (normal colon) cells. The in vitro tissue culture study demonstrated that the FPF 300-09 is more potent than the parent molecule (full-length zinc charged fetuin) in inducing apoptosis. FPF 300-09 has a LD₅₀ of 0.3-0.4 muM, while the LD₅₀ for zinc-charged fetuin is 3-10 muM.