IGF1R and neoplasm: For example, numerous growth factor receptors, such as type 1 insulin-like growth factor receptor (IGF-1R), mesenchymal-epithelial transition factor receptor (MET receptor), and the human epidermal growth factor receptor-2 (HER2) [86–88], can activate EGFR downstream effectors and trigger the ensuing intracellular signaling pathways by bypassing EGFR, thus inducing tumor cell proliferation and resistance to apoptosis (Figure 3).