Table 1.
Modulation of drug resistance to Dox by Verapamil and Cyclosporine A in HMECd1 and HMECd2
| HMEC-1 | HMECd1 | HMECd2 | |||||
|---|---|---|---|---|---|---|---|
|
Agents |
IC50 (μM) |
IC50 (μM) |
RI |
RF |
IC50 (μM) |
RI |
RF |
|
Dox |
0.052 ± 0.001 |
0.785 ± 0.049 |
15.09* |
1.00 |
1.257 ± 0.055 |
24.17* |
1.00 |
|
+ Vrp 1 μM |
0.051 ± 0.002 |
0.386 ± 0.075 |
7.56* |
1.99* |
0.225 ± 0.062 |
4.41* |
5.59* |
| + CysA 2.5μM | 0.049 ± 0.004 | 0.251 ± 0.041 | 5.12* | 3.13* | 0.159 ± 0.057 | 3.24* | 7.91* |
The cells were treated as described and tested by MTS assay. The resistance index (RI) was determined as the IC50 of Dox-treated HMECd1 or HMECd2 cells divided by the IC50 of Dox-treated HMEC-1 cells. The resistance fold (RF) was calculated as the IC50 of Dox-treated HMECd1 or HMECd2 cells over the IC50 of the same cell line as treated by Dox plus P-gp inhibitors. *p <0.05 for statistical significance.