奥曲肽通过G_0/G_1期阻滞抑制胆管癌细胞的增殖

Cytostatic effect of octreotide on human cholangiocarcinoma cell proliferation via a G_0/G_1 cycle block

为观察四种胆管癌细胞系 (RBE、NEC、QBC939、SSP 2 5 )是否能够表达生长抑素受体 (SSTR) ,以及八肽生长抑素类似物奥曲肽 (OCT)对胆管癌细胞的抑制作用 ,采用逆转录 聚合酶链反应方法检测四种细胞系 2 ,3型SSTR的表达 ;四氮唑蓝法检测不同浓度OCT (10、 1、 0 1、 0 0 1和 0 0 0 1mg L)在体外对胆管癌细胞增殖的影响。并应用碘化丙啶 (PI)及AnnexinV PI染色后于流式细胞仪检测经OCT作用后胆管癌细胞的细胞周期和凋亡情况。结果显示四种胆管癌细胞系均可以表达SSTR2 mRNA ,但未检测到SSTR3mRNA的表达。体外 10、 1和0 1mg LOCT明显抑制四种胆管癌细胞的增殖 (与各自对照组相比 ,P <0 0 5 ) ;1mg LOCT作用 4 8h后流式细胞分析表现为G0 G1 期细胞增加 ,S期和G2 M细胞减少 (与各自对照组相比 ,P <0 0 1) ,但没有明显凋亡发生。从而证明OCT抑制胆管癌细胞增殖的机制主要与引起细胞周期阻滞有关 ,而不是促进凋亡。对于表达生长抑素受体的胆管癌 。

To observe the expression of somatostatin receptor(SSTR) in four cholangiocarcinoma cell lines(RBE, NEC, QBC 939 , SSP 25), and to investigate the inhibitory effects of somatostatin analog octreotide (OCT) on the proliferation of them, Type 2 and 3 SSTR mRNA in cholangiocarcinoma cell lines were detected by reverse transcriptase polymerase chain reaction technique (RT PCR).The effects of various doses (10?1?0.1?0.01 and 0.001mg/L) of OCT on the proliferation of above cholangiocarcinoma cell lines were evaluated by MTT assays with serum free medium as control. The cell cycle and apoptosis of the cells with and without OCT treatment were analyzed in flow cytometry with propidium iodide (PI) staining and FITC conjugated Annexin V PI double staining. Not only SSTR 3 but also SSTR 2 mRNA were be detected in all cholangiocarcinoma cell lines. OCT (10, 1 and 0.1mg/L) significantly inhibited the proliferation of four cholangiocarcinoma cell lines in vitro (P values were all less than 0.05 when compared with control). After 48h of exposure to 1mg/L OCT, flow cytometric analysis demonstrated increased cell number of G 0/G 1 phase accompanied with decreased cell number of G 2/M and S phase (P values were all less than 0.01 when compared with control), while apotosis was not seen in all samples. The results proved that OCT inhibited proliferation of cholangiocarcinoma cells, this effect seems mainly due to cytostatic effect rather than promoting the way of apoptosis. Thereby, OCT may posess the perspectives in the adjuvant therapy for SSTR positive biliary tract malignancies.