Figure 4
Knockdown of LDH-A increases the sensitivity of breast cancer cell lines BT474 and MDA-231 to Taxol. A, BT474 cells were transfected with scramble siRNA (Ctr) or si-LDHA. 48 hrs after siRNA transfection, cell lysates were prepared and immunoblot analyses were carried out with antibodies against LDHA and β-actin. B, 48 hrs after siRNA transfection, cell lysates were prepared and LDHA activity was examined. Data are shown in percentage of LDH activity relative to Ctr-transfected cells. C, 48 hrs after siRNA transfection, cells were seeded into 96-well plates at the density of 8 × 103 cells per well. 12 hrs after incubation, the cells were then treated with various concentrations of Taxol for 48 hrs. Then the cell viability was detected using a MTS reagent. Data are presented as the percentage of viability inhibition measured in cells treated without Taxol. D, LDHA protein expression in MDA-MB-231 (Ctr) and stable LDHA knowdown MDA-MB-231 cells (sh-LDHA) were detected to evaluate the efficiency of LDH-A knockdown by using an LDHA antibody. β-actin was used as a loading control. E, LDH activity was examined in MDA-MB-231 cells with and without stably knockdown of LDH-A. Data are shown in percentage of LDH activity relative to Ctr cells. F, MDA-MB-231 cells with or without stably knockdown of LDH-A were seeded into 96-well plates at the density of 8 × 103 cells per well. 12 hrs after incubation, the cells were treated with various concentrations of Taxol for 48 hrs. Then the cell viability was detected using a MTS reagent. Data are presented as the percentage of viability inhibition measured in cells treated without Taxol. Columns, mean of three independent experiments; bars, SE.*, P < 0.05, **, P < 0.01, ***, P < 0.001.