EGFR and posterior cortical atrophy: Together, our data evidently showed the regulation of AREG‐induced PD‐L1 synthesis in PCa cells, a process that functionally involves EGFR and its downstream elements including but not limited to PI3K, Akt, mTOR, Mek1/2, Jak1/2, and NF‐κB, while p38, one of the major cellular stress sensors, did not seem to be engaged.