Li Gang, Zhong Yanping, Shen Qingrong, Zhou Yi, Deng Xiaofang, Li Cuiping, Chen Jiagui, Zhou Ying, He Min
Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.
Department of Pharmacy, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, Guangxi Zhuang Autonomous Region 530021, P.R. China.
Int J Oncol. 2017 Feb;50(2):405-413. doi: 10.3892/ijo.2017.3837. Epub 2017 Jan 3.
Never in mitosis gene A (NIMA)-related kinase 2 (NEK2) is a microtubule-associated protein that regulates spindle assembly in human cells and is overexpressed in various malignancies. However, the role of NEK2 in hepatocellular carcinoma (HCC) remains undetermined. We performed RNA-seq of the HCC cell line SMMC-7721 and the normal liver cell line HL-7702 using the Ion Proton System. NEK2 expression was detected using quantitative reverse transcription polymerase chain reaction in two cell lines and 5 matched HCC and adjacent non-tumorous liver tissues. The correlation between survival and NEK2 expression was analyzed in 359 patients with HCC using RNASeqV2 data available from The Cancer Genome Atlas (TCGA) website (https://tcga-data.nci.nih.gov/tcga/). The expression of NEK2, phospho-AKT and MMP-2 was evaluated by immunohistochemistry in 63 cases of HCC and matched adjacent non-tumorous liver tissues. Relationships between protein expression and clinicopathological parameters were assessed, and the correlations between NEK2 with phospho-AKT and MMP-2 expressions were evaluated. A total of 610 differentially expressed genes (DEGs) were revealed in the transcriptome comparison, 297 of which were upregulated and 313 were downregulated in HCC. NEK2, as the most obviously different DEG in cells and tissues from the RNA-seq data, was listed as an HCC candidate biomarker for further verification. NEK2 was overexpressed in HCC cells and tissues (P=0.002, P=0.013) and HCC patients with a high expression of NEK2 had a poor prognosis (P=0.0145). Clinical analysis indicated that the overexpression of NEK2 in HCC was significantly correlated with diolame complete (P<0.001), tumor nodule number (P=0.012) and recurrence (P=0.004). NEK2 expression was positively correlated with the expression of phospho-AKT (r=0.883, P<0.01) and MMP-2 (r=0.781, P<0.01). Overexpression of NEK2 was associated with clinicopathological characteristics and poor patient outcomes, suggesting that NEK2 serves as a prognostic biomarker for HCC. Alteration of NEK2 protein levels may contribute to invasion and metastasis of HCC, which may occur through activation of AKT signaling and promotion of MMP-2 expression.
有丝分裂相关基因A（NIMA）相关激酶2（NEK2）是一种微管相关蛋白，可调节人类细胞中的纺锤体组装，并且在多种恶性肿瘤中过表达。然而，NEK2在肝细胞癌（HCC）中的作用仍未确定。我们使用Ion Proton系统对HCC细胞系SMMC - 7721和正常肝细胞系HL - 7702进行了RNA测序。使用定量逆转录聚合酶链反应在两种细胞系以及5对匹配的HCC和癌旁非肿瘤肝组织中检测NEK2表达。利用从癌症基因组图谱（TCGA）网站（https://tcga - data.nci.nih.gov/tcga/）获得的RNASeqV2数据，分析了359例HCC患者的生存情况与NEK2表达之间的相关性。通过免疫组织化学评估了63例HCC及匹配的癌旁非肿瘤肝组织中NEK2、磷酸化AKT和MMP - 2的表达。评估了蛋白表达与临床病理参数之间的关系，并评估了NEK2与磷酸化AKT和MMP - 2表达之间的相关性。转录组比较共揭示了610个差异表达基因（DEG），其中297个在HCC中上调，313个下调。作为RNA测序数据中细胞和组织中最明显不同的DEG，NEK2被列为HCC候选生物标志物以进行进一步验证。NEK2在HCC细胞和组织中过表达（P = 0.002，P = 0.013），并且NEK2高表达的HCC患者预后较差（P = 0.0145）。临床分析表明，HCC中NEK2的过表达与肿瘤包膜完整性（P < 0.001）、肿瘤结节数量（P = 0.012）和复发（P = 0.004）显著相关。NEK2表达与磷酸化AKT（r = 0.883，P < 0.01）和MMP - 2（r = 0.781，P < 0.01）的表达呈正相关。NEK2的过表达与临床病理特征及患者预后不良相关，提示NEK2可作为HCC的预后生物标志物。NEK2蛋白水平的改变可能有助于HCC的侵袭和转移，这可能通过激活AKT信号通路和促进MMP - 2表达而发生。
