TABLE 1.
Cytotoxicity of mitoxantrone and modulation of drug resistance by PSC833 in human MDA-MB-435 cancer cells
| Pretreatment | MDA-MB-435 Cell Type | IC50 of Mitoxantrone | RFa | FSb | |
|---|---|---|---|---|---|
| μM | |||||
| None | wt | 0.2 ± 0.03 | 1.0 | 1.0 | |
| MDR | 1.6 ± 0.13 | 8.0* | 1.0 | ||
| PSC833 (3 mg/ml) | wt | 0.2 ± 0.04 | 1.0 | 1.0 | |
| MDR | 0.4 ± 0.02 | 2.0 | 4.0* | ||
*
p < 0.05, statistically significant difference in drug resistance
a
Resistance factor: IC50 of mitoxantrone in MDR cells divided by IC50 of same drug in the wt cells
b
-Fold sensitization: IC50 of mitoxantrone in wt or MDR cells divided by that in the same cells pretreated with PSC833