Fig. 3

Effects of OR-2003 and OR-2100 on in vitro tumor-suppressive activity. a Cell growth inhibition ratio. The IC₅₀ values (μM) of the compounds were analyzed after the treatment using multiple types of cancer cell lines. Although the IC₅₀ value varied among the cell lines, almost identical values were observed for DAC, OR-2003, and OR-2100. b Change in cell growth after treatment of compounds. The effect on growth of HCT116 cells was analyzed by monitoring their growth for 94 h using IncuCyte. OR-2003 and OR-2100 showed a decrease in the cell number similar to that of DAC. Results are shown as mean ± SD. c Reactivation of two tumor-suppressor genes. The re-expression of tumor-suppressor genes known to be methylated in HCT116 cells was analyzed. Both SFRP1 and UCHL1 showed re-expression in a dose-dependent manner. Each RT-qPCR analysis was performed thrice and the results are presented as mean ± SD. d Induction of gene expression by OR-2003 and OR-2100, along with DAC. Expression levels (log₂ values) of 58,341 probes obtained by an expression microarray were compared for non-treated cells (x-axis) and drug (1 μM)-treated cells (y-axis). Probes with no change were plotted on the black dashed line, and the genes upregulated more than twofold and to − 1.0 log₂ value by the drug treatment are surrounded by the trapezoid with red dashed lines. The numbers for DAC, OR-2003, and OR-2100 were 2011, 2060, and 2041, respectively