DUSP7 is a dual-specificity phosphatase that selectively dephosphorylates mitogen-activated protein kinases, displaying high activity toward ERK2 and lower activity toward p38 (MAPK14) and JNK (MAPK8). In mammalian cells, DUSP7 regulates chromosome 3 during mitosis by controlling phospho-ERK2 abundance through its phosphatase activity 1. Dysregulation of DUSP7 expression is implicated in multiple cancers: in estrogen receptor-positive breast cancer, downregulation of DUSP7 correlates with poor survival and estrogen-independent growth 2, while in cervical cancer, decreased DUSP7 expression associates with larger tumor size, parametrial infiltration, and adverse relapse and survival outcomes 3. DUSP7 protein stability is regulated by ubiquitination-mediated degradation 4. In colorectal cancer with SMAD4 deletion, loss of DUSP7 promotes disease progression through aberrant RAS/ERK signaling 5. Additionally, elevated DUSP7 expression in peripheral T cells correlates with inflammatory cytokine production in ankylosing spondylitis 6. The selective activity of DUSP7 toward ERK2 and its role in suppressing oncogenic RAS/ERK signaling make it a candidate for structure-based inhibitor development as a therapeutic strategy 7.