Overexpression of IFITM1 in NF1-associated MPNST cells caused a significant decrease in Ras activation (GTP-Ras) and downstream ERK1/2 phosphorylation, indicating that the expression level of IFITM1 was inversely correlated with tumor progression in NF1 (Figure 2). Here, IFITM1 is linked to malignant peripheral nerve sheath tumor.