TP53 and neoplasm: It has been shown that phosphorylation of B56γ3 at Ser510 by ATM is an important modification that strengthens the tumor-suppressive function of the PP2A/AB56γ3C complex after DNA damage by promoting the interaction between PP2A-B56γ3 and substrate tumor suppressor P53, which results in P53 dephosphorylation at Thr55 and transcriptional activation [13].