Induction of p73 expression after culture with 5-AC (RT-PCR). U2OS and HL60 were cultured with 5-AC for 3 and 5 days at 1 and 5 μmol/L, and 0.5 and 3 μmol/L, respectively. CEM, ALL-Sil, and KOPT-K1 were treated with 5-AC for 3 days at 3 μmol/L.