To find the potential association of AMPK with MLK3-JNK and to search for additional kinases upstream of AMPK independent of LKB1, we chose lung adenocarcinoma A549 cell line lacking LKB1 and established a stable A549 cell line by infection of lentivirus carrying LKB1 cDNA (Fig 2A). Here, MAPK8 is linked to lung adenocarcinoma.