MAPK3 and cancer: Interestingly, it has been shown that AQP5 activates the Epidermal Growth Factor Receptor (EGFR) and Extracellular signal-Regulated Kinases 1/2 (ERK1/2) pathway, resulting in tumor cell proliferation and migration [17, 18] Briefly, up-regulating AQP5 in tumor cells stimulates EGFR that in turn trigger the RAS/MAPK as well as phosphatidylinositol-3- kinase (PI3K)/AKT signal pathways; PI3K activates AKT which blocks caspase-9, finally hindering apoptosis in AQP5 expressing cancer cells [18, 19].