In addition, AMPK-independent actions of metformin have also been reported which include inhibition of mTOR signaling either through RAG GTPases [44], through enhancement of PRAS40-RAPTOR association in glioma [25], or through activation of JNK/p38 MAPK-mediated apoptotic pathway to inhibit lung cancer [24]. Here, MAPK8 is linked to central nervous system cancer.