DUSP1 is activated by phosphorylation on two Serine residues, Ser359 and Ser364 by ERK1/2 in human embryonic kidney (HEK) 293 cells; on the other hand, DUSP1 inactivates ERK1/2 by dephosphorylation in human bladder cancer HT1197 cells [23–25]. The gene discussed is MAPK3; the disease is urinary bladder cancer.