Lloyd Katie A, Moore Andrew R, Parsons Bryony N, O'Hara Adrian, Boyce Malcolm, Dockray Graham J, Varro Andrea, Pritchard D Mark
Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom.
Gastroenterology Directorate, Royal Liverpool and Broadgreen University Hospitals NHS Trust, Liverpool, United Kingdom.
Oncotarget. 2016 Jul 19;7(29):45462-45478. doi: 10.18632/oncotarget.9990.
Elevated circulating concentrations of the hormone gastrin contribute to the development of gastric adenocarcinoma and types-1 and 2 gastric neuroendocrine tumors (NETs). MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate proteins which in turn influence various biological processes. We hypothesised that gastrin induces the expression of specific gastric miRNAs within CCK2 receptor (CCK2R) expressing cells and that these mediate functionally important actions of gastrin.
Gastrin increased miR-222 expression in AGSGR cells, with maximum changes observed at 10 nM G17 for 24 h. Signalling occurred via CCK2R and the PKC and PI3K pathways. miR-222 expression was increased in the serum and gastric corpus mucosa of hypergastrinemic INS-GAS mice and hypergastrinemic patients with autoimmune atrophic gastritis and type 1 gastric NETs; it decreased in patients following treatment with the CCK2R antagonist netazepide (YF476). Gastrin-induced miR-222 overexpression resulted in reduced expression and cytoplasmic mislocalisation of p27kip1, which in turn caused actin remodelling and increased migration in AGSGR cells.
miRNA PCR arrays were used to identify changes in miRNA expression following G17 treatment of human gastric adenocarcinoma cells stably transfected with CCK2R (AGSGR). miR-222 was further investigated using primer assays and samples from hypergastrinemic mice and humans. Chemically synthesised mimics and inhibitors were used to assess cellular phenotypical changes associated with miR-222 dysregulation.
These data indicate a novel mechanism contributing to gastrin-associated gastric tumor development. miR-222 may also be a promising biomarker for monitoring gastrin induced premalignant changes in the stomach.
循环中胃泌素激素浓度升高会促进胃腺癌以及1型和2型胃神经内分泌肿瘤（NETs）的发生发展。微小RNA（miRNA）是一类小的非编码RNA，可在转录后调节蛋白质，进而影响各种生物学过程。我们推测胃泌素可诱导表达胆囊收缩素2受体（CCK2R）的细胞内特定胃miRNA的表达，并且这些miRNA介导胃泌素的重要功能作用。
胃泌素可增加AGSGR细胞中miR - 222的表达，在10 nM G17处理24小时时观察到最大变化。信号通过CCK2R以及PKC和PI3K途径传导。在高胃泌素血症的INS - GAS小鼠、患有自身免疫性萎缩性胃炎和1型胃NETs的高胃泌素血症患者的血清和胃体黏膜中，miR - 222表达增加；在用CCK2R拮抗剂奈扎肽（YF476）治疗后的患者中，miR - 222表达降低。胃泌素诱导的miR - 222过表达导致p27kip1表达降低和细胞质定位错误，进而导致AGSGR细胞中的肌动蛋白重塑和迁移增加。
使用miRNA PCR阵列鉴定用G17处理稳定转染CCK2R的人胃腺癌细胞（AGSGR）后miRNA表达的变化。使用引物分析以及来自高胃泌素血症小鼠和人类的样本对miR - 222进行进一步研究。使用化学合成的模拟物和抑制剂评估与miR - 222失调相关的细胞表型变化。
这些数据表明了一种导致胃泌素相关胃肿瘤发生发展的新机制。miR - 222也可能是监测胃泌素诱导的胃癌前病变的有前景的生物标志物。
