DUSP2 and gastric cancer: Exosome-associated transfer of miR-519a-3p from gastric cancer cells to intrahepatic macrophages induces M2 polarization of macrophages by suppressing Dual specificity protein phosphatase 2 (DUSP2) and escalating MAPK/ERK pathway, thus enhancing PMN formation and liver metastasis in gastric cancer [74].