Objective To investigate the role and molecular mechanism of membrane-associated guanylate kinase inverted 3(MAGI3) in glioma cell proliferation. Methods The expression levels of MAGI3 and PTEN were assessed in glioma samples by Western blotting. MAGI3 was stably transfected into C6 glioma cells to obtain C6-MAGI3 cells. Then, the proliferation, the expression levels of MAGI3 and PTEN, and Akt phosphorylation were evaluated in C6 and C6-MAGI3 cells. Xenograft tumor models were established by subcutaneous injection of C6 and C6-MAGI3 cells into nude mice, and the growth rates of xenografts in the mice were compared. The potential role of MAGI3 expression in PI3K/Akt signaling activation was further investigated by examining the correlation between MAGI3 expression and the expression of PI3K/Akt signaling downstream target genes in a glioma dataset using gene set enrichment analysis(GSEA). Results Expression levels of MAGI3 and PTEN were significantly downregulated in gliomas. Overexpression of MAGI3 in the glioma C6 cell line upregulated PTEN protein expression, inhibited the phosphorylation of Akt, and suppressed cell proliferation. MAGI3 overexpression also inhibited the growth of C6 glioma tumor xenografts in nude mice. Analysis based on the GEO database confirmed the negative correlation between activation of PI3K/Akt pathway and MAGI3 mR NA levels in human glioma samples. Conclusion The loss of MAGI3 expression in glioma may enhance the proliferation of glioma cells via downregulation of PTEN expression, leading to the activation of the PI3K/Akt pathway. MAGI3 is a potential glioma suppressor.
MA QianZHANG YanMENG RanXIE Kun MingXIONG YingLIN SongHE Zong Lin K.TAO TaoYANG YingZHAO Ji ZongHE Jun Qi
目的研究使用En Vision多标记读板仪检测细胞内钙信号的可行性。方法分别用卡巴胆碱和凝血酶刺激LN229、SKN-MC细胞或者磷脂酶C抑制剂U73122预处理的LN229细胞,使用En Vision多标记读板仪检测细胞内钙信号强度的变化。结果卡巴胆碱诱导的LN229细胞内钙信号变化呈现浓度依赖性;卡巴胆碱和凝血酶诱导的细胞内钙信号变化趋势不同;凝血酶诱导的钙信号变化具有细胞特异性;U73122对凝血酶诱导的钙信号的抑制作用呈现剂量依赖性。结论 En Vision多标记读板仪作为细胞内钙信号检测仪器,具有快速、可重复性好和灵敏度高等优势,适用于钙信号相关的研究和小分子抑制剂的筛选等领域的工作。
