Table 1 Drug treatment schedule of Caco-2, HCT-116-p53 null and HCT-116-p53 wild-type cell cultures

Single drug treatment (A)

Decitabine (µM)

0.5, 1, 3, 6, 12, 25

24 h, 48 h, 72 h, 96 h

4-PBA (mM)

0.5, 1, 3, 6, 12

24 h, 48 h, 72 h, 96 h

THU (µg/ml)

1, 10, 20, 30, 40, 80

48 h

Gene knockdown of CDA

ASO-CDA (nM)

50

24 h, 48 h, 72 h, 96 h

Combined drug treatment (B1-B2)

THU & Decitabine (B1)

THU (1, 10, 20, 30, 40, 80 µg/ml) + 5-deoxycytidine (3 µM)

72 h

Decitabine & 4-PBA (B2)

5-deoxycytidine (3 µM) + 4-PBA (3 mM) for 72 h, 4-PBA (3 mM) for another 48 h

120 h

Triple drug treatment (C1)

THU & Decitabine & 4-PBA

THU (40 µg/ml) + 5-deoxycytidine (3 µM) + 4-PBA (3 mM) for 72 h, THU (40 µg/ml) + 4-PBA (3 mM) for another 48 h

120 h

Gene knockdown of CDA and combined epigenetic drug treatment (C2)

ASO-CDA & Decitabine & 4-PBA

ASO-CDA (50 nM) 24 h, 5-deoxycytidine (3 µM) + 4-PBA (3 mM) for 72 h, 4-PBA (3 mM) for another 48 h

144 h