[Effects of sodium butyrate on proliferation and differentiation of human gastric carcinoma cell line AGS].

BACKGROUND & OBJECTIVE Sodium butyrate (NaBT) can inhibit proliferation and induce differentiation of various tumor cells. This study was to investigate effects of NaBT on the proliferation and differentiation of human gastric carcinoma cell line AGS and explore the possible mechanism. METHODS AGS cells were treated with 0, 1.0, 2.0 and 4.0 mmol/L of NaBT. Cell proliferation was detected by MTT assay; cell morphology changes were observed under optical and transmission electron microscopy; cell cycle was detected by flow cytometry (FCM). The expression of cyclin-dependent kinase inhibitor p21 was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. RESULTS After incubation with different concentrations of NaBT for 24 to 72 h, AGS cell proliferation was inhibited dramatically and the highest inhibition rate was 81.54%. The structure of AGS cells changed greatly. NaBT induced an increase of G0/G1 phase cells and a significant decrease of S phase cells accompanied by the changes in DNA ploidy. The expression of p21 was up-regulated at both mRNA and protein levels. NaBT exerted its effects in a dose-dependent manner. CONCLUSIONS NaBT could induce G1 arrest and inhibit cell proliferation in AGS cells by up-regulating the expression of p21. This could reverse the malignant phenotype of AGS to some extents.