28-hydroxy-3-oxoolan-12-en-2-oic acid and miR-451 synergistically inhibit the proliferation and migration of gastric cancer AGS cells and its possible mechanism / 中国肿瘤生物治疗杂志

@#[摘 要] 目的：探索南蛇藤提取物齐墩果烷型五环三萜（28-hydroxy-3-oxoolean-12-en-2-oic acid）协同miR-451对人胃癌AGS细胞增殖、迁移的影响及其可能的分子机制。方法：用miR-451过表达慢病毒感染AGS细胞，并用盐酸多西环素（DOX）10或100 ng/ml诱导24 h，构建过表达miR-451的细胞AGS/miR-451+。采用10、20、40、80、160 μmol/L的齐墩果烷型五环三萜处理AGS/miR-451+细胞，MTT法、划痕实验分别检测细胞增殖和迁移能力的变化，WB法检测细胞中mTOR通路及凋亡相关蛋白表达水平的变化。结果：成功构建过表达miR-451的AGS/miR-451+细胞。与未加药对照组相比，齐墩果烷型五环三萜处理后AGS/miR-451+细胞的增殖抑制率均呈时间和浓度依赖性升高（P<0.05或P<0.01），细胞迁移率均显著降低（P<0.05或P<0.01）。齐墩果烷型五环三萜处理组细胞中，mTOR 信号通路相关蛋白的表达量均有所降低（P<0.05或P<0.01）；凋亡相关蛋白中，Bcl2的表达量下降，BAX、caspase-3、caspase-1及细胞色素c的表达量升高（P<0.05或P<0.01）。结论：齐墩果烷型五环三萜能够协同miR-451抑制人胃癌AGS细胞的增殖与迁移，其机制可能与影响凋亡和mTOR信号通路相关蛋白的表达有关。

The p38 MAPK and NF-κB Pathways are Involved in Cyclic Compressive Force-induced IL-6 Secretion in MLO-Y4 Cells

ABSTRACT We previously revealed the involvement of extracellular regulated protein kinases 1/2 (ERK1/2) in interleukin-6 (IL-6) secretion induced by cyclic compressive force (CCF) in MLO-Y4 cells. In this study, we investigated the contributions of the p38 mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways to IL-6 secretion by stimulating MLO-Y4 cells with CCF. At 80% confluence, different magnitudes (1000μstrain, 2000 μstrain and 4000 μstrain), frequencies (0.5 Hz, 1.0 Hz and 2.0 Hz) and durations (10 min, 30 min, 1 h, 3 h and 6 h) of CCF were loaded onto cells using a four-point bending system. Flow Cytometry (FCM) analysis was used to analyze cell mortality rates after CCF loading. p38 and p65 phosphorylation as well as IκBα degradation in MLO-Y4 cells were detected by Western blotting (WB). Changes in IL-6 secretion after inhibitor treatment were assessed by enzyme-linked immunosorbent assays (ELISAs). Cellular viability was over 90 percent after CCF. p38 and p65 phosphorylation increased under all conditions, whereas IκBα protein levels decreased. However, phosphorylation and degradation were not completely dependent on the loading magnitude, frequency or duration. Furthermore, p38 inhibition using the specific inhibitor SB203580 reduced both p38 phosphorylation and IL-6 secretion. Similarly, NF-κB inhibition using BAY 11-7082 decreased p65 phosphorylation and IL-6 secretion but increased the concentration of IκBα. These findings reveal significant roles for the p38 and NF-κB signaling pathways in IL-6 secretion induced by CCF in MLO-Y4 cells.