Department of Gastroenterology, Jinshan Hospital, Fudan University, Shanghai Medical College of Fudan University, Shanghai, China.
J Dig Dis. 2012 Sep;13(9):453-8. doi: 10.1111/j.1751-2980.2012.00616.x.
To investigate the role of ghrelin in the gastric cancer cell line AGS and its probable mechanism.
Cell proliferation was detected by MTT assay after treated with ghrelin or des-acyl ghrelin. The expression of growth hormone secretagogue receptor 1a (GHS-R1a) and 1b (GHS-R1b) mRNA was detected using reverse transcription polymerase chain reaction (RT-PCR). The activity of extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt was measured by Western blot in cells either treated with ghrelin or inhibitors for ERK1/2 and phosphoinositide-3 kinase (PI3K). The distribution of cell cycle phases was determined by flow cytometry analysis of DNA content.
GHS-R1a and GHS-R1b mRNA were expressed in the AGS cells. Ghrelin and des-acyl ghrelin induced AGS cell proliferation at concentrations of 1 nmol/L and 10 nmol/L but had no proliferative effect at a concentration of 100 nmol/L. The treatment of AGS cells with 10 nmol/L of ghrelin and des-acyl ghrelin resulted in the progression of the increased cells in the S phase. ERK1/2 and Akt were activated by ghrelin and des-acyl ghrelin. Specific ERK1/2 inhibitor PD98059 and PI3K inhibitor wortmannin reduced phosphorylation of ERK1/2 and Akt, respectively and blocked ghrelin- and des-acyl ghrelin-induced AGS cell proliferation.
Ghrelin and des-acyl ghrelin stimulate the proliferation of gastric cancer cells via the activation of the ERK1/2 and PI3K/Akt pathway.
研究 ghrelin 在胃癌细胞系 AGS 中的作用及其可能的机制。
用 MTT 法检测 ghrelin 或去酰化 ghrelin 处理后细胞的增殖情况。采用逆转录聚合酶链反应（RT-PCR）检测生长激素促分泌素受体 1a（GHS-R1a）和 1b（GHS-R1b）mRNA 的表达。用 Western blot 法检测 ghrelin 或 ERK1/2 和磷酯酰肌醇-3-激酶（PI3K）抑制剂处理细胞后细胞外信号调节激酶 1/2（ERK1/2）和 Akt 的活性。通过流式细胞术分析 DNA 含量来确定细胞周期各时相的分布。
AGS 细胞中表达 GHS-R1a 和 GHS-R1b mRNA。ghrelin 和去酰化 ghrelin 在 1 nmol/L 和 10 nmol/L 浓度下诱导 AGS 细胞增殖，但在 100 nmol/L 浓度下无增殖作用。10 nmol/L 的 ghrelin 和去酰化 ghrelin 处理 AGS 细胞导致 S 期细胞增多。ghrelin 和去酰化 ghrelin 激活 ERK1/2 和 Akt。ERK1/2 特异性抑制剂 PD98059 和 PI3K 抑制剂 wortmannin 分别降低 ERK1/2 和 Akt 的磷酸化，阻断 ghrelin 和去酰化 ghrelin 诱导的 AGS 细胞增殖。
ghrelin 和去酰化 ghrelin 通过激活 ERK1/2 和 PI3K/Akt 通路刺激胃癌细胞增殖。
