NS-398, a selective cyclooxygenase 2 inhibitor, inhibited cell growth and induced cell cycle arrest in human hepatocellular carcinoma cell lines.
Cyclooxygenase 2 (COX-2) has been suggested to be associated with liver carcinogenesis. Several reports have shown that NSAIDs inhibit the growth of hepatocellular carcinoma cell lines. There is little evidence of how COX-2 inhibitors regulate the proliferation of hepatocellular carcinoma cells or the mechanism involved. In our study, we investigated the growth-inhibitory mechanism of a selective COX-2 inhibitor, NS-398, in 4 hepatocellular carcinoma cell lines by studying cell growth, COX-2 and proliferating cell nuclear antigen (PCNA) expression, cell cycle distribution and the evidence of apoptosis. NS-398 inhibited the growth of all 4 cell lines in a time- and dose-dependent manner and the inhibitory effects were independent of the level of COX-2 protein expression. PCNA expression was downregulated by NS-398 in a dose-independent manner. NS-398 caused cell cycle arrest in the S phase with a reduction in cell numbers and cell accumulation in the G0/G1 phase, for all 4 cell lines. No evidence of apoptosis was observed in our present study. Our findings suggest that a selective COX-2 inhibitor might serve as an effective tool for the chemoprevention and treatment of hepatocellular carcinomas. A reduction in cell number in the S phase may be an important event in cell cycle arrest caused by NS-398 in hepatocellular carcinoma cell lines.
Cheng
Jidong
J
Division of Hepatobiliary and Pancreatic Disease, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan. chjd@hyo-med.ac.jp
Imanishi
Hiroyasu
H
Amuro
Yoshiki
Y
Hada
Toshikazu
T
D015121:6-Ketoprostaglandin F1 alpha / Q000096:biosynthesis; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D006528:Carcinoma, Hepatocellular / Q000201:enzymology / Q000473:pathology* / Q000517:prevention & control; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects*; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D015232:Dinoprostone / Q000096:biosynthesis; D016193:G1 Phase / Q000187:drug effects; D006801:Humans; D007527:Isoenzymes / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000235:genetics; D008113:Liver Neoplasms / Q000201:enzymology / Q000473:pathology* / Q000517:prevention & control; D008565:Membrane Proteins; D009578:Nitrobenzenes / Q000494:pharmacology*; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D016192:Resting Phase, Cell Cycle / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016196:S Phase / Q000187:drug effects; D013449:Sulfonamides / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D008565:Membrane Proteins; D009578:Nitrobenzenes; D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger; D013449:Sulfonamides; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D015121:6-Ketoprostaglandin F1 alpha; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone