Levels of mTOR, phosphorylated S6K (P-S6K), and phosphorylated S6 (P-S6) are aberrantly upregulated in renal cysts in ADPKD and PKD mouse models (Tao et al., 2005; Shillingford et al., 2006; Wahl et al., 2006), and mTOR inhibition with rapalogs reduced cyst growth and kidney enlargement and preserved renal function in PKD rodent models (Torres et al., 2010). Here, MTOR is linked to autosomal dominant polycystic kidney disease.