APOE and gastric cancer: M2 macrophage-derived exosomes mediate the intercellular transmission from M2 macrophages to gastric cancer (GC) cells, sustaining the connection between M2-exosomal ApoE, leading to the activation of the PI3K/Akt signaling pathway to remodel the cytoskeleton, and facilitating GC cells migration (Zheng et al., 2018).