sentence: Given that homozygous deletion of MAP3K5 results in increased tumor initiation in a carcinogen induced model of skin cancer , that MAP3K9 regulates apoptosis via MAP2K4 / 7-JNK , and that diminished activation of JNK1 can result in enhanced survival of tumor cells , our data indicate that abrogation of this signaling axis ( Supplementary Fig. 4 ) is important for melanoma development .