Dual-specificity phosphatase 4 (DUSP4)

Dual-specificity phosphatase 4 (DUSP4), also known as MKP-2, is a nuclear-localized enzyme that plays a critical role in the negative regulation of mitogen-activated protein kinase (MAPK) signaling pathways [1, 3, 10]. It functions by dephosphorylating both the phosphoserine/threonine and phosphotyrosine residues of kinases such as ERK1/2, JNK, and p38, effectively inactivating them to control cellular processes like proliferation, differentiation, and apoptosis [1, 4, 16]. In oncology, DUSP4 is frequently investigated as a context-dependent biomarker; its loss is associated with poor prognosis and drug resistance in certain cancers like triple-negative breast cancer and clear cell renal cell carcinoma, while its overexpression can also contribute to survival in other malignant contexts [14, 15, 17]. Beyond cancer, DUSP4 has been implicated in neurodegenerative conditions such as Alzheimer’s disease, where its downregulation is observed in postmortem brain tissue and its overexpression has shown neuroprotective effects in animal models [2, 18]. As a therapeutic target, researchers are developing small-molecule inhibitors to modulate its activity, particularly to overcome resistance to targeted therapies or to sensitize tumor cells to chemotherapy [11, 13]. However, its dual role as both a tumor suppressor and an oncogene depending on the cellular environment necessitates careful patient selection and biomarker monitoring for drug development [15, 17].

Other names

MKP2MKP-2HVH2VH2TYPDual specificity protein phosphatase 4MAP kinase phosphatase 2VH1 homologous phosphatase 2Mitogen-activated protein kinase phosphatase 2

Competitive or allosteric inhibition of the catalytic phosphatase domain to prevent the dephosphorylation of target MAP kinases, thereby maintaining kinase activity and downstream signal transduction [9, 11, 13].