MAPK8 and neoplasm: After labeling IFIT3 with the STrEP Tag, protein complexes that formed after interaction of IFIT3-StrEP with proteins from the tumor cell lysate stained positive for JNK and STAT1 by Western Blot analysis, while other typical signaling proteins such as Akt, EGFR, MAPK and Src were not detectable (figure 3A).