This invention provides a novel human liver regeneration associated protein hLRTM4 and the polynucleotide which encodes the hLRTM4 protein. Furthermore, this invention provides a method of preparing and using hLRTM4 protein and its polynucleotides. hLRTM4 protein can be used to treat liver injury, and its antagonists (e.g. antisense nucleic acids and antibodies) can be used to treat hepatocellular carcinoma. This invention also provides the corresponding pharmaceutical compositions.