干扰素诱导跨膜蛋白3 在结肠癌组织中的表达及对结肠癌细胞凋亡的调控作用研究

目的 探讨干扰素诱导跨膜蛋白3（IFITM 3）在结肠癌组织中的表达及对结肠癌细胞凋亡的调控作用。方法 实时荧光定量聚合酶链反应（qRT-PCR）检测结肠癌组织和对应的癌旁组织中IFITM 3 的表达水平。细胞转染si-IFITM 3 抑制IFITM 3 的表达，同时转染si-control 作为对照，MTT 检测转染后48 h的细胞增殖情况。流式细胞术检测细胞凋亡情况。Western blot 检测细胞中Bcl-2、Bax、p-STAT3、STAT3蛋白表达水平。结果 IFITM 3 在结肠癌组织中的表达水平高于癌旁组织，差异有统计学意义（P <0.05）。si-IFITM 3 组结肠癌细胞HT29 和HCT116 的存活率与si-control 组相比下降，差异有统计学意义（均P <0.05）。转染si-IFITM 3 后的结肠癌细胞HT29 和HCT116 凋亡率高于si-control 组，差异有统计学意义（均P <0.05）。转染si-IFITM 3 后的结肠癌细胞HT29 和HCT116 中STAT3 蛋白表达水平没有变化，p-STAT3、Bcl-2 蛋白表达水平低于si-control 组，Bax 蛋白表达水平高于si-control 组。结论 干扰素诱导跨膜蛋白3在结肠癌组织中过度表达。抑制干扰素诱导跨膜蛋白3 的表达，可以抑制结肠癌细胞的增殖，促进癌细胞凋亡，其作用机制与Bcl-2、Bax、STAT3 有关。

Expression of IFITM3 in colon cancer tissue and its effect on apoptosis of colon cancer cells

Objective To investigate the expression of interferon-induced transmembrane 3 (IFITM3) in colon cancer tissues and its effect on the apoptosis of colon cancer cells. Methods The expression level of IFITM3 in colon cancer tissues and corresponding adjacent tissues was detected by qRT-PCR. Colon cancer cells were transfected with si-IFITM3, while si-control was used as a control. The proliferation of the transfected cells was detected by MTT.Cell apoptosis was detected by flow cytometry. Western blot was used to detect the expression levels of Bcl-2, Bax,p-STAT3 and STAT3 proteins in the cells. Results The expression level of IFITM3 in the colon carcinoma tissues was significantly higher than that in the adjacent tissues, and the difference was statistically significant (P < 0.05).The survival rates of colon cancer HT29 and HCT116 cells of the si-IFITM3 groups were significantly decreasedcompared with those of the si-control groups (P < 0.05). The apoptosis rates of colon cancer HT29 and HCT116 cells of the si-IFITM3 groups were significantly higher than those of the si-control groups, and the differences were statistically significant (P < 0.05). The expression levels of STAT3 in the si-IFITM3-transfected HT29 and HCT116 cells did not change compared with those in the si-control groups, but the expressions of p-STAT3 and Bcl-2 protein were significantly lower than those in the si-control groups, and Bax protein expression levels were significantly higher than those in the si-control groups. Conclusions IFITM3 is over-expressed in colon cancer tissues. Inhibition of IFITM3 expression can inhibit the proliferation of colon cancer cells and promote the apoptosis of the cancer cells, its mechanism is related to Bcl-2, Bax and STAT3.