Experimental study on the effect of Nimesulide to reverse multi-drug resistance of gastric cancer cell line

OBJECTIVE: To evaluate the influence of Nimesulide (NIM), a selective Cyclooxygenase-2(COΧ-2) inhibitor, on Mitomycin (MMC)-inhibited proliferation and MMC-induced apoptosis of gastric cancer cell lines SGC 7901 and SGC 7901/VCR and explore the mechanism of NIM reversing multi-drug resistance of gastric cancer cell lines SGC 7901/VCR.METHODS:1) MTT assay and clone formation rate were used to determine the influence of NIN on Mitomycin ( MMC)-inhibited proliferation of gastric cancer cell lines SGC 7901 and SGC 7901/VCR. 2) Apoptosis was determined by Acridine Orange (AO) staining and flow cytometry.RESULTS:1) Combined NIM and MMC compared to MMC alone, the IC 50 and clone formation rate decreased 0.74 μg/mL, 46.4% respectively in gastric cancer cell line SGC 7901, and the IC 50 went down from more than 2.0 μg/mL to 0.65 μg/mL, clone formation rate decreased 31% in gastric cancer cell line SGC 7901/VCR. 2) The AO staining positive cells of the NIM+MMC group was 47±1.00 and 30.33±4.16 in gastric cancer cell lines SGC 7901 and SGC 7901/VCR, respectively. It was enhanced noticeably compared with the other groups. The result of flow cytometry was similar to the result of AO staining.CONCLUSIONS:1) selective COX-2 inhibitors NIM can enhance drug toxicity of MMC to human MMC-inhibited proliferation and MMC-induced apoptosis of gastric cancer cell lines SGC 7901 and SGC 7901/VCR. 2) NIM has some effects on reversing multi-drug resistance of gastric cancer cell line SGC 7901/VCR.