Background
Microsomal prostaglandin E synthase (mPGES)-1 catalyzes the formation of prostaglandin (PG) E2 from cyclooxygenase (COX)-derived PGH2. mPGES-1 is induced by proinflammatory cytokines, such as IL-1β and tumor necrosis factor alpha, and is linked to conditions with high PGE2 biosynthesis and inflammation. A recent study has demonstrated enhanced COX-1 and COX-2 expressions in affected muscle tissues of patients with polymyositis (PM) and dermatomyositis (DM), suggesting their important role in the pathophysiology of these diseases. However, expression of mPGES-1 in muscle tissue has not been investigated.