[Serum-and-glucocorticoid-inducible-kinase-2 is overexpressed and mediates glycogen synthase kinase-3β/ β-catenin signal transduction in hepatocellular carcinoma]

Zhonghua Gan Zang Bing Za Zhi. 2020 Jan 20;28(1):43-46. doi: 10.3760/cma.j.issn.1007-3418.2020.01.011.
[Article in Chinese]

Abstract

Objective: To investigate the differential expression of serum-and-glucocorticoid-inducible-kinase-2 (SGK2) in hepatocellular carcinoma (HCC) and normal liver tissues and the related mechanism mediating signal transduction of GSK-3 β / β catenin in HCC cells. Methods: Twenty pairs of matched HCC and normal tissues were collected and the situation of expression of SGK2 mRNA was detected by real-time fluorescence quantitative PCR. Western blot was used to detect the levels of SGK2 protein in human HCC cell lines (Huh-7, SMMC-7721) and normal human liver cell line (L02). SGK2 siRNA was used to transfect human HCC cell lines (SMMC-7721 and Huh-7), and then the protein expression levels of GSK-3 β/ β - catenin was successfully detected with the above-mentioned transfected cell line by western blot. Measurement data were expressed as mean ± standard deviation (x±s), and the Student t -test was used as the statistical method. Results: SGK2 mRNA expression was up-regulated in all 20 HCC samples than that of the expression of matched normal liver tissues. SGK2 protein levels were significantly higher in Huh-7 and SMMC-7721 than normal human liver cell lines (P < 0.01). The downregulation of SGK2 expression in human HCC cell lines (SMMC-7721 and Huh-7) had inhibited the expression of unphosphorylated GSK-3 β. In addition, the downregulation of SGK2 expression in HCC cell lines had decreased the dephosphorylation of β - catenin to prevent degradation of the β - catenin proteasome. Conclusion: SGK2 is overexpressed in HCC and mediates GSK-3β/β- catenin signaling in HCC cells.

目的: 探讨血清和糖皮质激素诱导的蛋白激酶(SGK2)在肝癌组织与正常肝脏组织中的表达差异以及介导肝细胞癌(HCC)细胞中糖原合成酶激酶-3β(GSK-3β)/β-连环蛋白(β-catenin)信号传导的相关机制。 方法: 收集配对的HCC及正常组织20对,采用实时荧光定量PCR技术检测SGK2 mRNA表达情况。应用蛋白质印迹法检测人肝癌细胞系Huh-7、SMMC-7721以及正常人肝细胞系L02中SGK2蛋白水平。应用SGK2 siRNA转染人肝癌细胞系SMMC-7721、Huh-7,然后使用蛋白质印迹方法检测上述转染成功细胞系中GSK-3β、β-catenin的蛋白质表达水平。计量资料以均值±标准差(x±s)表示,统计学方法采用Student t检验。 结果: 与配对正常肝组织中的表达水平相比,所有20个HCC样品中SGK2 mRNA表达上调。在两种人肝癌细胞系(Huh-7和SMMC-7721)中SGK2蛋白水平显著高于正常人肝细胞系(P < 0.01)。在人HCC细胞系SMMC-7721和Huh-7中,SGK2表达下调抑制了未磷酸化GSK-3β表达。另外,在HCC细胞系中SGK2表达下调通过阻止β-catenin蛋白酶体降解来降低β-catenin的去磷酸化。 结论: SGK2在HCC中过表达并介导HCC细胞中GSK-3β/β-catenin信号传导。.

Keywords: Carcinoma, hepatocellular; Glutathione synthase kinase-3β; Phosphatidylinositol-3-kinase; Serum/glucocorticoid-regulated kinase 2; β-catenin.

MeSH terms

  • Carcinoma, Hepatocellular*
  • Cell Line, Tumor
  • Glucocorticoids
  • Glycogen Synthase Kinase 3
  • Glycogen Synthase Kinase 3 beta
  • Humans
  • Liver Neoplasms*
  • Signal Transduction
  • beta Catenin

Substances

  • Glucocorticoids
  • beta Catenin
  • Glycogen Synthase Kinase 3 beta
  • Glycogen Synthase Kinase 3