Perhaps two of the most validated biomarkers are urinary tissue-inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7), which are released by tubular cells in response to ischemia or injury, and their product [TIMP-2] x [IGFBP7] has been shown to be an accurate predictor of all-cause AKI [90, 91]. Here, IGFBP7 is linked to ischemia.