Fig. 3

Effects of SOX4 knockdown (SOX4-KO) on radiosensitivity and cisplatin chemosensitivity in head and neck squamous cell carcinoma cells. a, b Combination treatment of SOX4-KO with 5 Gy radiation or cisplatin resulted in significantly more apoptosis in PCI50 and SNU1041 cells than in control cells treated with 5 Gy radiation or cisplatin treatment alone. c, d SOX4-KO cells showed greater expression of cleaved caspases-3 and −7, and cleaved poly-ADP ribose polymerase (PARP), and less X-linked inhibitor of apoptosis protein (XIAP), than did control cells after 5 Gy radiation or cisplatin treatment (^*P < 0.05). C: negative control siRNA transfected cells; S: SOX4-specific siRNA transfected cells (SOX4-KO); Cis: cisplatin treatment; IR: irradiation