EGFR and neoplasm: Nevertheless, EGFR not only presents on tumor cell surface, it also controls many different processes in normal tissues and cells, such as the differentiation and proliferation of astrocytes at late embryonic and neonatal stages of cortical development [25], the efficient differentiation of mesenchymal cells in the semilunar valves of the heart [26], as well as the cell proliferation and cell-cycle entry of hepatocytes following tissue injury [27], all of which limit the clinical applications of EGF-SubA.