RESUMEN
Objective To investigate the effects of selective COX-2 inhibitor nimesulide on growth inhibition,apoptosis and expression of COX-2 of human esophageal carcinoma Eca-109 cell line; and analyzed the correlation with the anti-oncogene,P277~(kip1). Methods MTT assay was used to detect the proliferation of Eca-109 cell. Apoptosis and cell cycle were determined by electronic microscopy and flow cytometry. The expression of COX-2 mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR),the protein expression of COX-2 and P277~(kip1) were examined by Western blot analysis. Results Nimesulide significantly inhibited the proliferation of Eca-109 cell line in a time-and dose-depenent fashion; increased the proportion of cells in the G_0/G_1 phase and induced apoptosis of the cells in a dose-dependent(manner). Meanwhile,nimesulide can down-regulated the expression of COX-2 and up-regulated the expression of P277~(kip1) protein.Conclusion Nimesulide can inhibit the proliferation of Eca-109 cells,cause G_0/G_1 phase cell cycle arrest and induce apoptosis.The mechanism is probably explained with down-regulation of the expression of COX-2 and up-regulation of P277~(kip1) expression.