Previous data indicates that the PI3K/Akt/mTOR pathway is the most activated pathway associated with radioresistance in three PCa-IRR cell lines (DU145-IRR, PC3-IRR, and LNCaP-IRR) developed by irradiating these with 2 Gy per day for only five consecutive days [31, 32]. The gene discussed is MTOR; the disease is posterior cortical atrophy.