However, the role of α-KG in tumorigenesis is controversial; for example, in p53-deficient pancreatic ductal adenocarcinoma (PDAC), α-KG is involved in P53-mediated tumor suppression by specifically upregulating 5-hydroxymethylcytosine (5 hmC) to elevate tumor suppressor gene expression [37]. Here, TP53 is linked to neoplasm.