NPC1 and neuroblastoma: To further confirm that TSA could ameliorate the phenotype induced by pathological cholesterol accumulation, we pre-treated SH-SY5Y neuroblastoma cells with U18666A, a compound that can mimic the accumulation of unesterified cholesterol in late-endosomal/lysosomal compartments similar to that occurring in NPC1-deficient fibroblasts.