IRS2 and neoplasm: IRS2 is a cytoplasmic adaptor protein that mediates the activity of insulin and IGF-1 receptors, activating the downstream PI3K/AKT/mTOR and MAPK pathways.7 IRS2 is expressed in various malignancies and contributes to unique tumor cell metabolism, motility, and invasion.8 In CRC, IRS2 mRNA and protein levels increase with progression from normal tissue to adenoma and carcinoma and dysregulated IRS2 expression activates the PI3K/AKT/mTOR pathway and enhances cell adhesion.9