Similarly, exposure to high levels of extracellular ATP can also tilt the signaling mechanism from a P2X7-phosphatidylinositol 3-kinase/Akt-mediated growth pathway to a novel P2X7-AMPK-mammalian target of rapamycin (mTOR)-mediated autophagic pathway, as observed in tumor cells (Bian et al., 2013). Here, P2RX7 is linked to neoplasm.