To further investigate the functional consequences of CHKA on AR signaling, we used a reporter assay to assess AR transactivation capacity in C4-2 PCa cells and observed a 2.5-fold decrease (P < .001) in R1881-induced AR transcriptional activity following CHKA knockdown using siCHKA (Figure 3A). The gene discussed is CHKA; the disease is posterior cortical atrophy.