Although neither PCa tumourigenesis nor primary tumour growth is controled by Gal-8 expression, we demonstrate for the first time the key role played by Gal-8 in the metastatic process controlling the actin filament reorganization and filopodia formation and E-Cadherin expression, which in turn allow effective migration and survival of circulating tumour cells along the metastatic process. This evidence concerns the gene LGALS8 and posterior cortical atrophy.