GDF15
Growth/differentiation factor 15 (GDF15) was first identified as Macrophage inhibitory cytokine-1 or MIC-1. It is a protein belonging to the transforming growth factor beta superfamily. Under normal conditions, GDF-15 is expressed in low concentrations in most organs and upregulated because of injury of organs such as liver, kidney, heart and lung. The function of GDF-15 is not fully clear but it seems to have a role in regulating inflammatory pathways and to be involved in regulating apoptosis, cell repair and cell growth, which are biological processes observed in cardiovascular and neoplastic disorders. GDF-15 has shown to be a  strong prognostic protein in patients with different diseases such as heart diseases and cancer. Metformin was shown to cause increased levels of GDF-15. This increase mediates the effect of body weight loss by metformin. A monoclonal antibody (mAB1) that neutralizes circulating GDF-15 is being tested in mice and non-human primates as a potential treatment for cancer-related cachexia.