MTOR and neoplasm: Chemokine receptors may potentially facilitate tumor dissemination at each of the crucial steps of metastasis, including the adherence of tumor cells to endothelium, extravasation from blood vessels, metastatic colonization, angiogenesis, proliferation, and the escape from the host's response through the activation of certain pathways, such as ERK/MAPK, PI-3K/AKT/mTOR, or JAK/STAT and others.