TP53BP2 (tumor protein p53 binding protein 2) is a regulatory protein that plays crucial roles in apoptosis, cell cycle control, and cellular stress responses. The gene produces two alternatively spliced proteins, 53BP2S (1005 amino acids) and 53BP2L/ASPP2 (1128 amino acids), through inclusion or exclusion of exon 3 1. TP53BP2 enhances p53-mediated apoptosis by promoting p53's DNA binding and transactivation function on proapoptotic gene promoters, while also inhibiting cell cycle progression at G2/M 1. Beyond p53 regulation, TP53BP2 demonstrates diverse cellular functions including autophagy regulation through Beclin-1/Bcl-2 complex modulation 2 and interferon response enhancement via SOCS2 suppression and JAK/STAT pathway facilitation 3. In disease contexts, TP53BP2 expression is associated with improved interferon-α treatment responses in chr1 hepatitis B patients, with specific genetic variants predicting HBsAg loss 3. The protein is also implicated in preeclampsia pathogenesis through increased autophagy 2 and breast cancer progression, where miR-548d-3p-mediated TP53BP2 downregulation promotes proliferation and inhibits apoptosis 4. TP53BP2 expression is regulated by DNA methylation and histone modifications, affecting its transcriptional activity 5.