Table 2. Cytotoxicity of 5-methylchrysene (5MC) in cell lines expressing hCYP1B1 or hCYP1A1, alone or together with hGSTP1.
Cytotoxicity was assayed by the sulforhodamine dye method as described in Materials and Methods. Each value represents the mean ± standard deviation of three or more independent assays.
| Cell lines | IC50 values (μM 5MC) |
Fold-Resistance |
|---|---|---|
| V79MZ | 3.1 ± 0.2 | (N/A) |
| hCYP1B1 | 1.6 ± 0.2 a | (1.0) |
| hCYP1B1 + hGSTP1-25 | 3.1 ± 0.3 b | 2.0 |
| hCYP1B1 + hGSTP1-15 | 2.9 ± 0.4 b | 1.9 |
| hCYP1A1 | 1.6 ± 0.2 a | (1.0) |
| hCYP1A1 + hGSTP1-23 | 3.2 ± 0.3 c | 2.0 |
a
Significantly different (P ≤ 0.05) from the mean for V79MZ;
b
Significantly different (P < 0.05) from the mean for hCYP1B1;
c
Significantly different (P < 0.05) from the mean for hCYP1A1.