The selective cyclooxygenase-2 inhibitor nimesulide induces apoptosis in pancreatic cancer cells independent of COX-2.
BACKGROUND
Selective cyclooxygenase-2 (COX-2) inhibition reduces the growth of many cancer cell lines, and this effect may be mediated through induction of apoptosis. This study was designed to investigate the effects of the COX-2 inhibitor nimesulide on the growth of human pancreatic cancer cells.


METHODS
Reverse transcriptase-polymerase chain reaction analysis, northern blotting, and immunoblotting were used to demonstrate COX-2 mRNA and protein in two pancreatic cancer cell lines: BxPC-3 and MIA PaCa-2. The effect of nimesulide on cell growth was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and cell count. Apoptosis was determined by FACS analysis, DNA laddering, and assessment of the floating cell/attached cell ratio. Caspase-3 activation was evaluated by measuring caspase-3 cellular activity and by determining the effects of two caspase inhibitors on cell viability.


RESULTS
COX-2 mRNA was detected in both cell lines. Immunoblotting confirmed COX-2 protein expression in only the BxPC-3 cell line. Nimesulide decreased cell viability and inhibited cell growth in both cell lines. Incubation with 100 micromol/L nimesulide increased the fraction of apoptotic cells and the floating cell/attached cell ratio in both cell lines. DNA laddering was observed after incubation with nimesulide for 96 hours. There was no increase in caspase-3 activity within 96 hours.


CONCLUSIONS
The selective COX-2 inhibitor nimesulide is antimitogenic in pancreatic cancer cells, which is independent of COX-2 expression. This effect in part is mediated by the induction of apoptosis.
Eibl
Guido
G
Division of General Surgery, David Geffen School of Medicine, University of California at Los Angeles, California CA 90095-6904, USA.
Reber
Howard A
HA
Wente
Moritz N
MN
Hines
Oscar J
OJ
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins; D010190:Pancreatic Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D013449:Sulfonamides / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D013449:Sulfonamides; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; C012655:nimesulide