Thyroid hormone-inducible hepatic protein is a protein  similar to the gene product of S14, a rat gene whose expression is limited to liver and adipose tissue and is controlled by nutritional and hormonal factors. This gene has been shown to be expressed in liver and adipocytes, particularly in lipomatous modules. It is also found to be expressed in lipogenic breast cancers, which suggests a role in controlling tumor lipid metabolism.

Enhanced long-chain fatty acid synthesis may occur in breast cancer, where it is necessary for tumor growth and predicts a poor prognosis. The S14 protein functions to activate genes encoding the enzymes of fatty acid synthesis. Amplification of chromosome region 11q13, where the THRSP gene resides, also predicts a poor prognosis in breast tumors.