Over the past several decades, we demonstrated that extracellular ATP could promote cancer cell invasion via the P2Y2 and P2X7 receptors to regulate epithelial-mesenchymal transition (EMT) and invasion-associated molecules, including IL-8, E-cadherin, Snail, Claudin-1, β-catenin, S100A4, HIF-2α, and SOX9, as well as through activation of epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling [7–14]. Here, MAPK3 is linked to cancer.