SSd affects p53 expression and downstream targets in 143B and MG-63. Cells were treated with SSd (80 µmol/l) for 48 h and (A) protein and (B) mRNA levels of p53, p21, p27, cyclinD1, Bax and cleaved-caspase-3 were determined by western blot and reverse transcription-quantitative polymerase chain reaction, respectively. ***P<0.001. SSd, saikosaponin D; p, tumor protein; Bax, B-cell lymphoma-2-like protein 4.