MTOR and cancer: Interestingly, mutations in PI3K/Akt/mTOR signaling have been found in BM, but not in primary tumors.10 Also, activation of this signaling pathway has already been associated with leptomeningeal dissemination in melanoma patients.47 We have shown that PI3K/mTOR pathway inhibition with dactolisib decreased cancer migration and invasion, and downregulated UBE2C both in vitro and in vivo.