Dual specificity protein phosphatase 28 (DUSP28), also called VHP, functions as a protein-serine/threonine phosphatase (EC 3.1.3.16) and a protein-tyrosine-phosphatase (EC 3.1.3.48). It is an atypical DUSP that contains the catalytic dual specificity phosphatase domain but lacks the N-terminal Cdc25/rhodanese-like domain that is present in typical DUSPs or MKPs. It has been implicated in hepatocellular carcinoma progression and in migratory activity and drug resistance of pancreatic cancer cells. DUSP28 has an exceptionally low phosphatase activity due to the presence of bulky residues in the active site pocket resulting in low accessibility.