Figure 6
From: An in vitro model and the underlying pathways of sinonasal inverted papilloma development
Possible mechanism of EGFR exon 20 mutation induced SIP development. The specific mutation of EGFR in epithelial cells leading to ligand-independent activation of EGFR. Uncontrol EGFR activation resulting in increased activation of PI3K/AKT and MAPK signaling pathways. Aberrant activation of these signaling pathways involves several cellular processes including cell proliferation, migration, and invasion. In SIP, EGFR exon 20 mutations induce increased expression of PI3K, p-AKT, and p-MAPK. After PI3K/AKT and MAPK signaling pathways are activated leading to increased cell migration and invasion abilities of the cells. This aggressiveness might be the factor that involved or enhanced the cells to grow invert into the underlying supportive tissue which is the characteristic of SIP.
