SNAI1 and melanoma: The caspase-3/7 activity experiments showed that the apoptosis activities in the NC+NC group, KD+NC group, and KD+OE group were 6348 ± 248.6, 12381.67 ± 138.87, and 6408.67 ± 371.30, respectively (Figure 7C), indicating that the apoptosis in DDX39-knockdown melanoma cells can be inhibited by SNAIL overexpression (P < 0.001).