OBJECTIVETo investigate the effect of Actinidia chinensis Planch polysaccharide (ACPS) on the growth and apoptosis of human gastric cancer SGC-7901 cells, and to explore the effect of SGC-7901 cells on p-p38 expression.

METHODSThe inhibition rates at different concentrations of ACPS on SGC-7901 cells at 24, 48, and 72 h were detected using CCK-8 method. Apoptosis ratios in SGC-7901 were determined by flow cytometry after 48-h treatment of different concentrations of ACPS. The expression of pro-caspase-9, PARP, and p-p38 in SGC-7901 cells after treated by different concentrations of ACPS was detected using Western blot. The expression of pro-caspase-9, PARP, and p-p38 was detected after SGC-7901 cells were pre-treated by p38 specific inhibitor.

RESULTSCompared with the control group, the optical density of SGC-7901 cells decreased after treated by 1, 2.5, 5, and 10 mg/mL ACPS (P < 0.05). Meanwhile, the longer the acting time, the lower the optic density (P < 0.01). IC50 was 7.43 mg/mL at 24 h; 3.88 mg/mL at 48 h, and 1.32 mg/mL at 72 h respectively. ACPS suppressed the protein expression of pro-caspase-9 (P < 0.01) and up-regulated the expression of PARP (89KD) (both P < 0.01). Further study showed that the protein expression of p-p38 was up-regulated in SGC-7901 cells treated by ACPS of different concentrations at 24 h (P < 0.05). The expression of phosphorylation p38 and the ACPS induced apoptosis of SGC-7901 cells could be inhibited after treated by specific inhibitor for 2 h.

CONCLUSIONSACPS could inhibit the growth of SGC-7901 cells and induce apoptosis. The underlying mechanism of inducing apoptosis was partially due to activating the p38MAPK path and further activating Caspase9 and PARP, finally leading to cell death.