Moreover, phosphorylation states of AKT and S6 were significantly enhanced upon siRNA knockdown of PTEN in cancer cells, suggesting AKT/mTOR signaling is activated upon loss of PTEN. In contrast, PTEN overexpression significantly inhibits phosphorylation of AKT and S6 in all the six cancer cell lines (Figures 4B, C). The gene discussed is AKT1; the disease is cancer.