In our previous study, we found that p38MAPK phosphorylates RB at the novel N-terminal S249/T252 sites71 to block PCa cell proliferation, a process that leads to an increase in the cell cycle CDK inhibitor p27, followed by G0-G1 cell cycle arrest and cellular quiescence3. The gene discussed is CDKN1B; the disease is posterior cortical atrophy.