Prostaglandins, especially
prostaglandin E2 (
PGE2), and COX-2 play an important role in
carcinogenesis of many
tumors including
bladder cancer (BCA). The
PGE2 receptors EP1-4 regulate
tumor cell growth, invasion and migration in different
tumor entities but EP expression in BCA remains to be determined. In the present study we examined the expression of EP1-4 in
non-muscle invasive bladder cancer (
NMIBC), muscle invasive
bladder cancer (MIBC) and normal urothelial tissue (NU) using immunohistochemistry. Nuclear and cytoplasmic EP1-4 expression was correlated with clinicopathological parameters and survival of BCA patients. EP1, EP2 and EP3 were significantly less expressed in the cytoplasm und nucleus of
NMIBC and MIBC than in NU; EP4 cytoplasmic staining in MIBC was significantly higher compared to NU. The cytoplasmic staining was significantly more abundant in MIBC than in
NMIBC in all investigated receptors except EP2. The level of EP staining in
NMIBC was correlated with staging and grading, especially cytoplasmic EP1. Nuclear staining of EP1 was an independent predictor of BCA recurrence-free survival in
NMIBC patients. EP receptors are dysregulated in BCA. The increase of EP1 may be used as prognostic parameter in
NMIBC patients and its dysregulation could be targeted by specific EP1 inhibitors.