Human epidermal growth factor (EGF)[17] and hepatocyte growth factor (HGF)[18] up-regulate AQP3 expression via the extracellular signal-regulated kinase (ERK) pathway, then promote cell migration and proliferation in vitro, suggesting that AQP3 could be a potentially important determinant of tumor growth and the spread of GC. The gene discussed is EGF; the disease is gastric cancer.