ERK1/2 activation in PCa cells was regulated by Class IA PI3K isoforms, Src, and FAK in LNCaP cells treated with CXCL13; however, both Class IA and Class IB PI3K isoforms as well as Src and FAK could lead to ERK1/2 phosphorylation in PC3 cells treated with CXCL13 (Figure 7). The gene discussed is PTK2; the disease is posterior cortical atrophy.