Our demonstration that fibronectin has a punctate pattern of expression within PCa cells, and co-localizes with PDI, Tgn46, Rab5 and Rab7, suggests that fibronectin is localized within vesicles in the ER, Golgi, early endosomal and late endosomal compartments. The gene discussed is FN1; the disease is posterior cortical atrophy.