Differential gene regulation by 9-cis and all-trans retinoic acid in neuroblastoma cells

Effect of Fas, FasL and Caspase-3 on apoptosis of retinoic acid-induced gastric carcinoma cells

AIM: To explore the effect on apoptosis of retinoic acid (RA)-induced BGC-803 gastric carcinoma cells and its relationship with the expression of Fas, FasL and Caspase-3.

METHODS: BGC-803 cells were treated with different concentrations of RA (0.001, 0.01, 0.1, 1, 10, 20 μmol/L) for 72 h. Then methyl-tetrazolium (MTT) assay was performed to determine the growth inhibition of BGC-803 cells; cell apoptosis rate was determined using flow cytometry; the feature of cell apoptosis was observed by Hoechst33342/PI staining; the mRNA expression of Fas, FasL and Caspase-3 were estimated using reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS: After BGC-803 cells were treated with RA (0.1-20 μmol/L) for 72 h, RA inhibited the growth of cells significantly compared with that in the control group (32.61%, 44.42%, 48.14%, 51.15% vs 0.657%; all P < 0.01). Cells in G₂/M were significantly increased after the cells were treated with 20 μmol/L RA for 12 h, 24 h and 48 h. G₁ peak specific to apoptosis was observed and also observed were chromatic agglutination and rupture of caryon membrane. Expressions of Fas, FasL and Caspase-3 mRNA were up-regulated significantly by RA for 48 h compared with that in the control group.

CONCLUSION: Fas, FasL and Caspase-3 are involved in gastric carcinoma cell apoptosis induced by RA.