In addition, some metabolism-related genes were also mutated in GIST, including IGF1R, INSR, IRS1, IRS2, MAX, MTOR, TSC1, and TSC2. To better understand the potential relationships among the proteins encoded by these 36 genes, these proteins were used to construct PPI networks, and a PPI network including 30 genes was obtained, suggesting that most of these proteins are functionally associated (Figure 4D). This evidence concerns the gene IRS2 and gastrointestinal stromal tumor.