STAT3 and neoplasm: It is also evident by numerous in vitro and in vivo reports that γ-tocopherol, δ-tocopherol, and vitamin E metabolite 13’-carboxychromanol have potent anti-cancer activities via modulating key signaling and several mediators that regulate tumor progression and cell death for example PI3K, NF-κB, STAT3, sphingolipid and eicosanoids metabolism [95].