Shen Chen-Tian, Wei Wei-Jun, Qiu Zhong-Ling, Song Hong-Jun, Luo Quan-Yong
Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, PR China.
Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, PR China.
Mol Cell Endocrinol. 2016 Oct 15;434:108-15. doi: 10.1016/j.mce.2016.06.013. Epub 2016 Jun 18.
Circulating afamin (AFM) concentrations have been investigated as a tumor biomarker in various types of carcinomas. However, suitable cell lines expressing human afamin have not yet been reported and current knowledge of the functions of afamin, particularly at the mechanistic molecular level, is very limited. In the current study, thyroid cancer cell lines 8505c and K1 were used to investigate the potential functions of afamin. AFM over-expression models and vector controls of 8505c (8505c + AFM and 8505c + NC) and K1 (K1 + AFM and K1 + NC) were successfully established by Lenti-LV5-AFM and Lenti-LV5-NC transfection. The change of gene expression was detected by qRT-PCR and western blotting analysis. (18)F-FDG imaging in xenografts model was performed using a micro PET/CT. We found that protein level of GAPDH, GLUT1, HK2, p-AKT, AKT, p-mTOR and PARP1 were up-regulated in K1 + AFM cells when compared to K1 and K1 + NC. While in 8505c, 8505c + NC and 8505c cells, the expression level of these genes were not significantly changed. (18)F-FDG uptake was much higher in K1 + AFM cells when compared to K1 and K1 + NC in vitro and in vivo. In conclusion, afamin could promote glycometabolism by up-regulating the glucose metabolism key enzymes in papillary thyroid carcinoma. These findings reveal new clues of the molecular function of AFM.
循环中脱辅基脂蛋白A（AFM）的浓度已被作为多种类型癌症的肿瘤生物标志物进行研究。然而，尚未有关于表达人脱辅基脂蛋白A的合适细胞系的报道，并且目前对于脱辅基脂蛋白A功能的了解，尤其是在分子机制层面，非常有限。在本研究中，甲状腺癌细胞系8505c和K1被用于研究脱辅基脂蛋白A的潜在功能。通过慢病毒载体Lenti-LV5-AFM和Lenti-LV5-NC转染，成功建立了8505c（8505c + AFM和8505c + NC）和K1（K1 + AFM和K1 + NC）的AFM过表达模型和载体对照。通过qRT-PCR和蛋白质免疫印迹分析检测基因表达的变化。在异种移植模型中使用微型PET/CT进行（18）F-FDG成像。我们发现，与K1和K1 + NC相比，K1 + AFM细胞中甘油醛-3-磷酸脱氢酶（GAPDH）、葡萄糖转运蛋白1（GLUT1）、己糖激酶2（HK2）、磷酸化蛋白激酶B（p-AKT）、蛋白激酶B（AKT）、磷酸化哺乳动物雷帕霉素靶蛋白（p-mTOR）和聚（ADP-核糖）聚合酶1（PARP1）的蛋白水平上调。而在8505c、8505c + NC和8505c细胞中，这些基因的表达水平没有显著变化。在体外和体内，与K1和K1 + NC相比，K1 + AFM细胞对（18）F-FDG的摄取要高得多。总之，脱辅基脂蛋白A可通过上调甲状腺乳头状癌中葡萄糖代谢关键酶来促进糖代谢。这些发现揭示了AFM分子功能的新线索。
