Objective      To determine the effect of 3

3-diindolylmethane (DIM) on inhibiting proliferation and invasion in gastric carcinoma SGC-7901 cells.       Methods      The proliferation of gastric cancer SGC-7901 cells treated with different concentrations (0

10

20

40 and 80 μmol/L) of DIM was detected by MTT assay. The invasive ability of SGC-7901 cells treated with 40 μmol/L of DIM was detected with Transwell chamber assay. The expression of PDGF-D and β-catenin in SGC-7901 cells and the concentrations of MMP-2 and MMP-9 in culture supernatant were detected by Western blotting and ELISA

respectively.       Results      Different concentrations of DIM inhibited the proliferation of gastric cancer cells (P0.05)

and the inhibitory effect was associated with DIM concentration. There was no statistically significant difference between 40 and 80 μmol/L. The invasive ability of SGC-7901 cells was significantly reduced by 75.2% after treatment with 40 μmol/L of DIM for 24 h (125.4±10.8 vs 31.1±4.5

P0.05). The expression of PDGF-D and β-catenin was decreased by 55.8% and 52.5%

respectively (P0.05). The concentrations of MMP-2 and MMP-9 in culture supernatant were significantly decreased after DIM treatment (23.5±2.6 vs 13.2±1.9; 30.4±2.4 vs 15.8±2.1

P0.05).       Conclusion      DIM inhibits gastric carcinoma cell proliferation and invasion through down-regulating the expression of PDGF-D

β-catenin

MMP-2 and MMP-9.