Knockdown of HSP27 restores the sensitivity to cisplatin in C13* in vitro. (A) C13* cells were transfected with HSP27 small interfering RNA for 48 h. C13* cells were negative control (NC). Confirmation of HSP27 protein knockdown by Western blot (upper panel). Cell viability was assayed after treatment with increasing concentrations of cDDP for 48 h by CCK-8. Data are shown as the mean ± 95% confidence interval from two independent experiments. (B) Total protein was isolated 48 h posttransfection, and PARP, c-PARP, and p-AKT, HSP27 expression was analyzed by Western blotting. (C) The average percentage of apoptosis in the transfected cells was 10.87% for C13*, which was significantly greater than that found in the nontransfected multidrug-resistant controls 3.75%. (D) Expression of caspase 3 in si-HSP27 and negative control.