The present invention relates to TCF mutant having a novel amino acid sequence which is obtained by mutagenesis of one or more amino acid between N-terminus and the first kringle of the amino acid sequence of native TCF and has lowered affinity to heparin and/or elevated biological activity. The present TCF mutant is prepared by gene manipulation of TCF. The TCF mutants of the present invention have proliferative activity and/or growth stimulative activity in hepatocyte and beneficial as a therapeutic agent for various hepatic diseases and an antitumor agent.