The histone chaperone protein, anti-silencing function 1B (ASF1B), is also highly expressed in PCa tissues and siRNA knockdown of ASF1B was shown to result in a significant decline in viability and colony formation as well as an increase in apoptosis and cell cycle arrest of both LNCap and C4-2 cells [57]. This evidence concerns the gene ASF1B and posterior cortical atrophy.