ACKR3 and Alzheimer disease: To compare the effects of CXCR7 to that of a known co-regulator of AR-mediated transcription, AD-LNCaP cells were co-transfected with an expression vector encoding α-actinin-4, a protein that enhances or represses AR activity when expressed at low and high doses, respectively, in mammalian cells (Figure 6A) [53].