IGFBP5 and neoplasm: Dormant brain tumors like GBMs secrete high levels of thrombospondin, angiomotin, and insulin-like growth factor-binding protein 5 (IGFBP5) against a background of low endothelial-specific marker 1 (ESM1) and epithelial growth factor receptor (EGFR) to induce and sustain the tumor mass dormancy program [97,102] in a thrombospondin-mediated PI3K pathway [98,103].