SLC6A8 and posterior cortical atrophy: Genetic silencing of the creatine transporter gene depletes intracellular creatine levels and decreases the colony-forming capacity of PCa cells, and in vitro treatment of PCa cells with a creatine analog cyclocreatine led to a marked decrease in intracellular levels of creatine, phosphocreatine, and creatinine and suppressed cell proliferation [42].