This pathway is heavily mutated in human cancers, harboring several prevalent oncogenes, including genes encoding PI3K subunits and AKT, and also several tumor suppressors, for example, PTEN and INPP4B (Fruman and Rommel, 2014, Mayer and Arteaga, 2016, Okkenhaug et al., 2016, Thorpe et al., 2015). The gene discussed is PTEN; the disease is cancer.