Table 2.
Cytotoxicity of compounds A, B, 1–4 towards sensitive and drug-resistant cancer cell lines and normal cells, as determined by the resazurin assay
| Cell lines | Compounds (μM) and degrees of resistance (in brackets) | ||||||
|---|---|---|---|---|---|---|---|
| Flavonoid derivatives | Doxorubicin | ||||||
| A | B# | 1 | 2 | 3 | 4 | ||
| CCRF-CEM | 7.85 ± 0.82 | 10.67 ± 0.73 | (−) | (−) | 18.07 ± 2.04 | (−) | 0.20 ± 0.06 |
| CEM/ADR5000 | 15.03 ± 1.02 | 18.60 ± 2.60 | (−) | (−) | 19.70 ± 1.86 | (−) | 195.12 ± 14.30 |
| Degree of resistancea | (1.91) | (1.74) | (1.09) | (975.60) | |||
aThe degree of resistance was determined as the ratio of IC50 value of the resistant/IC50 sensitive cell line; 5,7-dihydroxy-3-(1′-hydroxy-1′-phenyl-methyl)-6-methoxy-chroman-4-one (A), 2′,4′-dihydroxy-3′,6′-dimethoxychalcone (B); 5-hydroxy-6-methoxy-7-O-(3′,3′-dimethylprop-2′-enyl)chroman-4-one (1), 5-acetyl-6-methoxy-7-O-(3′,3′-dimethylprop-2′-enyl)chroman-4-one (2), 2′-hydroxy-3′,6′-dimethoxy-4′-O-(3″,3″-dimethylprop-2″-enyl)chalcone (3), 2′-acetyl-3′,6′-dimethoxy-4′-O-(3″,3″-dimethylprop-2″-enyl)chalcone (4).(−):>125 μM; # data previously reported [4]