HSP90 is a molecular chaperone that facilitates the conformational maturation of more than 200 proteins including cell survival and oncogenic signaling proteins, such as MYC, AKT, and nuclear receptors including AR and glucocorticoid receptor (GR) 13, 16, which play important roles in the development and progression of PCa. The gene discussed is HSP90AA1; the disease is posterior cortical atrophy.