MADD is a downstream target of PTEN in triggering apoptosis.

Mitogen-activated kinase activating death domain containing protein (MADD) is abundantly expressed in cancer cells and necessary for maintaining cancer cell survival. However, this survival function of MADD is dependent upon its phosphorylation by protein kinase B (Akt). The tumour suppressor PTEN (phosphatase and tensin homolog deleted on chromosome 10) is a lipid phosphatase that negatively regulates the phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway.