生长抑素对胆囊癌细胞株的致凋亡研究

Research of GBC-SD cell apoptosis induced by somatostatin

目的通过前期实验发现，生长抑素（somatostatin，SST）作用于胆囊癌细胞株（GBC—SD）后，可显著增强阿霉素（doxorubicin，DOX）的杀伤能力。该实验旨在研究SST对GBCSD细胞的诱导凋亡作用，并探讨其发生机制。方法GBCSD细胞分为4组：单独SST作用组、单独DOX作用组、联合用药组（SST预处理24h后，再加入DOX）和对照组。药物作用24、36、48和60h后，采用FITC—AnnexinV／Pl试验分别检测各组GBCSD细胞的凋亡情况；另外运用Western印迹方法检测SST作用24h后，GBCSD细胞内P53蛋白和Bax蛋白表达的变化。结果SST分别作用24、36、48和60h后，GBC-SD细胞没有出现明显的细胞凋亡，SST的致凋亡作用仅仅表现出微弱的时间依赖性；而在SST作用24h后，GBCSD细胞内的P53蛋白和Bax蛋白的表达都没有明显的变化（P〉0．05）。结论SST不能诱导GBC—SD细胞产生明显的细胞凋亡，P53蛋白和Bax蛋白在其中发挥着重要作用。

Objective In the previous research, after the treatment of somatostatin, the lethal effects of doxorubicin on gallbladder carcinoma were significantly enhanced. To identify the cytotoxici ty of SST on GBC SD cells, apoptosis index of GBC-SD cells after treatment of somatostatin or doxo rubicin or co-use of somatostatin and doxorubicin was observed. Methods GBC-SD cells were divided into four groups.. SST-alone-treated group, DOX-alone treated group, co-treated group （co-treatment of SST and DOX） and the control group. In control group, the cells were cultivated by medium only. In SST-alone treated group, the cells were cultivated by medium with SST in the concentration of 75 μg/ml. In DOX alone-treated group, the cells were cultivated by medium with DOX in the concentra tion of 5 μg/ml. In the co treated group, cells were firstly cultivated by medium with 75 μg/ml SST for 24 h, followed by the addition of DOX in the concentration mentioned above. After treatment of the GBC SD cells, apoptotic index was determined by FITC-Annexin V/PI assay at 24, 36, 48 and 60 h, respectively. Twenty-four hours after the treatment of SST, the expressions of P53 and Bax in GBC SD cells was examined by western blot. Results After treatment of SST, no significant ceil ap optosis occurred. Only a weak time dependent cytotoxicity of SST was observed. And 24 h after treat ment of SST, the expression of P53 and Bax did not significantly varied either. Conclusion SST can not induce significant apoptosis of GBC-SD cells, in which P53 and Bax may play a critic role.