Table. 1.

IC50 value in K562 cells and K562/DOX cells

Group IC50 (µM) RI RF
K562 K562/DOX
DOX 1.63 ± 0.20 38.2 ± 0.58* 23.43 -
DOX + IMP (2.78 µM) 2.06 ± 0.18 9.38 ± 0.07*,† 4.55 5.15
DOX + IMP (5.56 µM) 1.93 ± 0.09 4.56 ± 0.13*,† 2.36 9.93
DOX + IMP (11.10 µM) 2.08 ± 0.19 3.50 ± 0.07*,† 1.68 13.95

Data are shown as means ± SD, n = 3. K562 and K562/DOX cells were incubated with various concentrations of DOX (0.36–92.00 µM) in the presence or absence of IMP (2.78, 5.56, 11.10 µM) for 48 h, respectively. The cytotoxicity was evaluated by CCK-8 assay. IC50 (µM) values were calculated using the Bliss method. RI was calculated by dividing the IC50 for K562/DOX cells by that of K562 cells. RF was calculated as the ratio between the IC50 value of DOX alone to that of IMP combined with DOX in K562/DOX cells. IC50, 50% inhibiting concentration; RI, resistance index; RF, reversal fold; DOX, doxorubicin; IMP, imperatorin; CCK-8, Cell Counting Kit-8. *p < 0.05 vs. respective K562 cells; †p < 0.05 vs. respective DOX alone group.

Korean J Physiol Pharmacol 2022;26:145-155 https://doi.org/10.4196/kjpp.2022.26.3.145
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