胃泌素促进胃癌细胞增殖和血管生成拟态形成

Gastrin promoting the proliferation and vasculogenic mimicry of gastric cancer cells

目的探讨胃泌素对胃癌细胞血管生成拟态（VM）的作用及其分子机制。方法应用免疫细胞化学检测SGC-7901、AGS细胞中胃泌素受体（CCK-BR）；用终质量浓度为10、100nmol／L胃泌素处理SGC-7901和AGS72h，噻唑蓝（MTF）比色法检测细胞增殖率、实时定量聚合酶链反应（Real-timePCR）检测缺氧诱导因子-1α（HIF-1α）的表达、酶联免疫吸附实验检测血管内皮细胞生长因子（VEGF）的分泌水平；三维培养SGC-7901和AGS，用10、100nmol／L胃泌素处理，显微镜下观察24、48、72hVM形成，计数72hVM形成数；软琼脂克隆形成实验检测细胞培养3周的克隆形成率。结果SGC-7901和AGS细胞表达CCK-BR；经10、100nmol／L的胃泌素处理后，SGC-7901和AGS的细胞增殖率和克隆形成率高于对照组，细胞的环形、半环形VM形成数也高于对照组（P〈0．01）；细胞中HIF-1α的表达量比对照组上调了5．39、11．00（SGC-7901）、4．12和6．06倍（AGS）；分泌性VEGF的浓度也比对照组增高[298、339μg/mg蛋白（SGC-7901）及168和281μg／mg蛋白（AGS），P〈0．01]。结论通过胃泌素-CCK-BR-HIF-1α-VEGF构成的信号传递链，胃泌素促进胃癌细胞的体外增殖及VM的形成。

Objective To＇study the effects of gastrin on vaseulogenie mimicry （VM） and its mo- lecular mechanism in gastric cancer cells. Methods Cholecystokinin B receptor （ CCK-BR ） expression was detected by using immunoeytoehemistry in SGC-7901 and AGS cells. After treatment with gastrin at the final concentrations of 10 and 100 nmol/L for 72 h, methyl thiazol tetrazolium （MTT） , real-time quantita- tive polymerase chain reaction （Real-time PCR） and enzyme linked immunosorbent assay （ELISA） were used to determine the cell proliferation rate, hypoxia inducible factor （HIF） -1 α expression and vascular endothelial growth factor （VEGF） secretion. SGC-7901 and AGS cells were cultured by three-dimensional manner and treated with 10 and 100 nmol/L gastrin. The VM formation was observed at 24, 48 and 72 h by inverted microscope and the tubelike structure number was counted at 72 h. Cell clone formation rate following culture for 3 weeks was detected by clone formation assay. Results CCK-BR was expressed in SGC-7901 and AGS cells. After treatment with gastrin at the final concentrations of 10 and 100 nmol/L the cell proliferation rate and colony formation rate were higher than control group （ P 〈 0. 05 for all）. The number of the half-ring and ring VM in gastrin-treated groups was greater than that in control group （ P 〈 0. 05 for all）. Relative expression quantify of HIF-1α mRNA was 5.39 and 11 times （SGC-7901） and 4. 12 and 6. 06 times （AGS） higher than that in control group, and the concentrations of VEGF in culture medium were 298 and 339 μg/mg protein （SGC-7901） and 168 and 281 μg/mg protein （AGS） respec- tively, and higher than in control group （P 〈 0. 05 for all）. Conclusion Gastrin could promote cell prolif- eration and VM formation of gastric cancer cells, in vitro, through the signaling axis constructed by gastrin, CCK-BR, HIF-1α and VEGF.