To determine whether DHT can serve as a physiological signal and dynamically regulate HSD17B4 protein levels in PCa, we cultured LNCaP cells under hormone-deprived conditions for 24 h, followed by treating the cells with DHT at different concentrations for another 24 h, and found that 10 nM extracellular DHT dramatically decreased the protein level of HSD17B4 (Figure 4A). This evidence concerns the gene HSD17B4 and posterior cortical atrophy.