MAPK9 and neoplasm: Importantly, the level of phospho-JNK in B16-RCKD and 4T1-RCKD clones was markedly attenuated by JNK2 and JNK1 shRNA, respectively (Figure 4d), reinforcing the notion that IL-17RC silencing induces differential acquired-activation of distinct JNK isoforms in the two tumor cell lines.