Inhibition of heat shock protein 70 (HSP70) expression by HSP70 siRNA induces caspase-dependent apoptotic cell death in pancreatic cancer cells. (A) Inhibition of HSP70 expression by HSP70 siRNA leads to decreased viability in the MiaPaCa-2 pancreatic cancer cell line at 72 h. Viability was measured by the MTT assay. Two different sequences of HSP70 siRNA were used to rule out any off-target effects of siRNA. n = 3, *p<0.05. (B) Inhibition of HSP70 expression by two different sequences leads to caspase 3 activation. n = 3, *p<0.05. MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.