Effects of ?-tocopheryl on enhancement of TRAIL to induce apoptosis of gastric carcinoma cell lines SGC-7901 and MKN28 / 解放军医学杂志

ABSTRACT

Objective To study the effects of ?-tocopheryl succinate (?-TOS) on apoptosis of gastric cancer cells induced by TRAIL. Methods The cell cycles and the percentage of apoptosis were analyzed with flow cytometer and the expressions of NF-?B, survivin, bcl-2 and caspase-3 in gastric cancer cells were assessed with Western blot. Results After being exposed to TRAIL 300ng/ml for 24 hours, the apoptosis rate was 36.05% for MKN28 and 11.80% for SGC-7901. When exposed to ?-TOS at 60?mol/L for 24 hours, the apoptosis rate was 9.0% for MKN28 and 8.5% for SGC-7901. With a combination of ?-TOS 60?mol/L and TRAIL 300ng/ml for 24 hours, the apoptosis rate was elevated to 48.1% for SGC-7901 and 63.7% in MKN28, respectively. The results of Western blot showed that TRAIL inhibited the expressions of NF-?B and survivin, while had no inhibition on the expressions of bcl-2 of SGC-7901 and MKN28 cell lines. The expression levels of bcl-2 and survivin had no change when the cells were exposed to ?-TOS alone. When the cells were treated with ?-TOS and TRAIL simultaneously, the expressions of NF-?B, bcl-2, and survivin were greatly decreased. Conclusions ?-TOS can enhance the activity of TRAIL in inducing apoptosis, and the down-regulation of the expression of NF-?B, bcl-2 and survivin may be involved in the mechanisms.