Inflammation may activate stem cells via prostaglandin E2 (PGE2) production mediated by cyclooxygenase-2 (COX-2) expression. We performed an immunohistochemical analysis of the expression of stemness markers (Oct3/4 and CD44v6) and COX-2 in urinary bladder tissues obtained from cystitis and cancer patients with and withoutSchistosoma haematobiuminfections. Immunoreactivity to Oct3/4 was significantly higher inS. haematobium-associated cystitis and cancer tissues than in normal tissues. CD44v6 expression was significantly higher in bladder cancer withoutS. haematobiumthan in normal tissues. COX-2 was located in the cytoplasmic membrane, cytoplasm, and nucleus of the cancer cells. Interestingly, the nuclear localization of COX-2, which was reported to function as a transcription factor, was significantly associated with the upregulation of Oct3/4 and CD44v6 in bladder cancer tissues with and withoutS. haematobiuminfection, respectively. COX-2 activation may be involved in inflammation-mediated stem cell proliferation/differentiation in urinary bladder carcinogenesis.
Cyclooxygenase-2 dependent and independent antitumor effects induced by celecoxib in urinary bladder cancer cells
