Table II.
Comparison of the IC50 values of DOX and drug-reversing ratio of As2O3 at different time-points.
| Factor | Treatment | −rhG-CSF
|
+rhG-CSF
|
|
|---|---|---|---|---|
| 24 h | 48 h | 48 h | ||
| IC50 to DOXa | As2O3 (0.1 µM) | 23.46±3.30 | 14.35±1.84 | 19.28±2.16 |
| As2O3 (0.5 µM) | 9.52±1.02 | 4.28±0.55 | 6.85±1.31 | |
| CsA (4 µg/ml) | 7.62±0.83 | 5.98±0.71 | 7.73±2.24 | |
| SGC7901/ADM | 34.31±4.38 | 26.94±3.67 | 32.39±4.52 | |
| SGC7901/S | 5.17±0.46 | 3.93±0.42 | 5.49±0.68 | |
| Drug-resistance ratiob | 6.63 | 6.85 | 5.90 | |
| Drug-reversal ratioc | As2O3 (0.1 µM) | 1.46 | 1.87 | 1.68 |
| As2O3 (0.5 µM) | 3.60 | 6.29 | 4.72 | |
| CsA (4 µg/ml) | 4.50 | 4.51 | 4.19 | |
a
Data are presented as the mean ± standard deviation.
b
Drug resistance ratio was calculated as the IC50 of resistant cells to that of SGC7901/S cells.
c
Reversal ratio was calculated as the IC50 of resistant cells to the reversal-agent treated cells. As2O3, arsenic trioxide; CsA, cyclosporin A; IC50, half maximal inhibitory concentration; DOX, doxorubicin; rhG-CSF, recombinant human granulocyte colony stimulating factor.