EGFR and cancer: To investigate the regulatory role of hSulf-1 in heparin-binding growth factor signaling in human cancers, the previous studies identified that hSulf-1 expression can diminish the cascade phosphorylation of a series of kinases including epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK), mitogen-activated protein kinase kinase (MEK), serine/threonine kinase (AKT) after treatment with exogenously added growth factors, and followed by inactivation of downstream signaling pathways [6], [11], [12].