CASP9 and cancer: In contrast, reduced expression of cleaved caspase 9 and 3, the active form of these two proteins, were detected in DUSP16-expressing cells compared to vector-expressing cells in all four types of cancer cells (Fig. 4A–C and Supplementary Fig. 2D), demonstrating that DUSP16 regulates cisplatin-mediated cell death through inhibiting the activation of caspase 9 and caspase 3.