PI3K/Akt通路在缺氧活化钙敏感受体介导的A549细胞转移中的作用

目的探讨PI3K/Akt信号通路在缺氧活化钙敏感受体(calcium sensing receptor,Ca SR)介导的A549及A549/DDP细胞转移中的作用。方法将处于对数生长期的A549及A549/DDP细胞随机分为对照组、缺氧组、缺氧+Gd Cl_3(Ca SR激动剂)组、缺氧+NPS2143(Ca SR抑制剂)组、缺氧+LY294002(PI3K通路抑制剂)+Gd Cl_3组。应用Western blot分析不同处理情况下,Ca SR、MMP-2及p-Akt蛋白在A549、A549/DDP细胞的表达水平;采用细胞划痕及Transwell小室方法,检测不同处理因素对细胞迁移和侵袭能力的影响;应用ELISA法,分析不同处理因素对A549及A549/DDP细胞分泌MMP-2蛋白的影响。结果与对照组比较,缺氧能够增强A549及A549/DDP细胞Ca SR的表达,增强细胞迁移能力,提高细胞及培养液中MMP-2蛋白表达水平、促进Akt蛋白的磷酸化,NPS2143能减弱缺氧的作用,Gd Cl_3放大缺氧的作用,而LY294002抑制缺氧和Gd Cl_3的上述作用。结论缺氧活化Ca SR促进A549及A549/DDP细胞转移,其机制可能涉及PI3K/Akt通路。

Role of PI3K/Akt pathway in hypoxic-activated calcium sensing receptor mediated A549 cell metastasis

Aim To explore the role of PI3K/Akt signaling pathway in A549 and A549/DDP cells metastasis mediated by hypoxic-activated calcium sensing receptor(CaSR). Methods The A549 and A549/DDP cells in the logarithmic growth stage were randomly divided into control, hypoxia, hypoxia+GdCl 3(CaSR agonist), hypoxia+NPS2143(CaSR inhibitor) and hypoxia+LY294002(PI3K inhibitor)+GdCl 3 group. The protein levels of CaSR, MMP-2 and p-Akt were analyzed by Western blot in A549 and A549/DDP cells under different treatment conditions. The effects of different treatment factors on the ability of cell migration and invasion were measured by wound scratch assay and transwell migration assay. The effects of different treatment factors on the secretion of matrix metalloproteinase-2(MMP-2) protein by A549 and A549/DDP cells was analyzed by ELISA. Results Compared with control group, hypoxia increased the protein expression of CaSR, enhanced cell migration ability, increased MMP-2 protein expression in cells and culture medium, and promoted Akt protein phosphorylation in A549 and A549/DDP cells. NPS2143 reduced the effect of hypoxia, GdCl 3 amplified the effect of hypoxia, and LY294002 inhibited effect of hypoxia and GdCl 3. Conclusions Hypoxic-activated CaSR promotes A549 cell metastasis, and its mechanism may involve PI3K/Akt pathway.