Inhibition of Human Glioma Cell Growth by a PHS-2 Inhibitor, NS398, and a Prostaglandin E Receptor Subtype EP1-selective Antagonist, SC51089

Prostaglandin H synthase (PHS) is a key enzyme in the synthesis of prostaglandins (PGs). Recently, enhanced expression of PHS-2 in brain tumors and the correlation between the PHS-2 level and the histopathological grade of glioma has been reported. Furthermore, in vitro inhibition of glioma cell growth by a specific PHS-2 inhibitor, NS398, has been demonstrated. It has also been shown that prostaglandin E2 (PGE2) contributes to colon carcinogenesis by binding to the prostaglandin E receptor subtype EP1. We therefore evaluated the effects of NS398 and two EP1 antagonists, SC51089 and AH6809, on glioma cell lines.