NLGN4Y and posterior cortical atrophy: To further understand the role of NLGN4Y in PCa progression, we ectopically expressed the protein in NLGN4Y-null PC-3 cells and in LNCaP cells, in which low endogenous NLGN4Y mRNA can be detected by qPCR at high amplification cycles, but protein expression is hardly detectable by western blot (Supplementary Figure S4A).