MTOR and neoplasm: In contrast to previous studies showing the ability of highly metastatic cells to assist low metastatic cells in obtaining a metastatic ability [51–53], we discovered that low metastatic cells could assist lung metastasis of highly metastatic cells using at least two mechanisms: by secreting exosomal Wnt7a that increases the capacity of highly metastatic cells via activation of the PI3K/Akt/mTOR signaling pathway and by increasing angiogenesis in the tumor microenvironment for a better escape of highly metastatic cells.