PTEN and cancer: Confirmation that TMEPAI regulates PTEN and PI3K signaling was shown both by TMEPAI knockdown in cancer cells, which resulted in increased PTEN protein and decreased Akt phosphorylation (Figs. 5A) and by TMEPAI overexpression in normal cells (Fig. 5B), which caused reduced PTEN and increased Akt phosphorylation, mimicking the signaling status of the cancer cells.