title: The influence of cyclooxygenase-1 expression on the efficacy of cyclooxygenase-2 inhibition in head and neck squamous cell carcinoma cell lines.
abstract: We have previously observed that cyclooxygenase-2 (COX-2) inhibition blocked the production of vascular endothelial growth factor (VEGF) in some head and neck squamous cell carcinoma (HNSCC) cells. However, as some HNSCC cells showed little response to COX-2 inhibition, although they highly expressed COX-2 and prostaglandin E2, we set out to elucidate what made this difference between them and focused on the possibility of the differential expression of COX-1. In western blotting, we found that COX-1 was expressed in SNU-1041 and SNU-1066, but not in SNU-1076 and PCI-50. Only in those cell lines without expression of COX-1 was VEGF production blocked meaningfully by small interfering RNA of COX-2. However, by cotreating with small interfering RNAs of COX-2 and COX-1, VEGF synthesis and prostaglandin E2 were inhibited in SNU-1041 and SNU-1066, similarly in SNU-1076 and PCI-50 with high expression of only COX-2. We also found that there was no difference in the pattern of prostaglandin synthesis between COX-2 and COX-1 through enzyme-linked immunosorbent assay for various prostaglandins. Our study suggests that, as COX-1 and COX-2 express and affect VEGF synthesis in HNSCC cells, we should check COX-1 expression in investigations on cancer treatment by inhibiting COX-2-induced prostaglandins.
authors.affiliation: Cancer Research Institute Seoul National University College of Medicinestitute, Seoul, Korea.
authors.forename: Seok-Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Hyo-Sun
authors.initials: HS
authors.lastname: Kim
authors.forename: Myung-Sun
authors.initials: MS
authors.lastname: Choi
authors.forename: Ji-Eun
authors.initials: JE
authors.lastname: Kim
authors.forename: Woo-Jin
authors.initials: WJ
authors.lastname: Jeong
authors.forename: Dae-Seog
authors.initials: DS
authors.lastname: Heo
authors.forename: Myung-Whun
authors.initials: MW
authors.lastname: Sung
mesh_terms: D002277:Carcinoma / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D002294:Carcinoma, Squamous Cell; D045744:Cell Line, Tumor; D051545:Cyclooxygenase 1 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology*; D015232:Dinoprostone / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D006258:Head and Neck Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D006801:Humans; D018307:Neoplasms, Squamous Cell / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics; D015398:Signal Transduction; D000077195:Squamous Cell Carcinoma of Head and Neck; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000378:metabolism
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D034741:RNA, Small Interfering; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D015232:Dinoprostone