TIMP2 and acute kidney injury: Furthermore, research has identified a set of kidney-specific cell-free methylation markers, such as postmeiotic segregation increased 2-like 2 (PMS2L2) recombinant tissue inhibitors of metalloproteinase 2 (TIMP2), which can be utilized to monitor the occurrence and progression of SA-AKI, offering new possibilities for early diagnosis and treatment (Zhang et al., 2023; Xu et al., 2024; You et al., 2024).