Objective: To investigate the correlation of CEP192 expression with prognosis of gastric cancer and biological behaviors of gastric cancer cells.
Methods: Public databases and clinical tissue samples were used to examine CEP192 expression level in gastric cancer. Kaplan-Meier survival curves, univariate and multivariate Cox regression analyses, ROC curves and bioinformatics analyses were used to explore the risk factors affecting the 5-year postoperative survival, the correlation of CEP192 expression level with the patients' survival, and its biological role in gastric cancer development. In gastric cancer MGC-803 cells with lentivirus-mediated CEP192 interference or overexpression, cell proliferation and expressions of PLK1, CDK1 and Cyclin B1 were examined with CCK-8 assay and Western blotting. The effects of CEP192 knockdown or overexpression on tumorigenesis of MGC-803 cells was observed in nude mice, and the expressions of PLK1, CDK1 and Cyclin B1 in the xenografts were detected.
Results: CEP192 was highly expressed in gastric cancer and associated with poor prognosis of the patients (P < 0.05). High expression of CEP192, CEA ≥5 ng/mL, CA199 ≥37 IU/mL, T3-4 stage, and N2-3 stage were independent risk factors affecting the patients' 5-year postoperative survival (P < 0.05). Bioinformatics analyses suggested that CEP192 was involved in several vital biological processes and positively regulated cell cycle progression. In MGC-803 cells, CEP192 knockdown significantly inhibited cell proliferation and lowered the expression levels of PLK1, CDK1, and Cyclin B1, while its overexpression produced the opposite effects. In the nude mouse models, CEP192 knockdown resulted in lowered tumorigenic potential of MGC-803 cells and decreased protein levels of PLK1, CDK1, and Cyclin B1 in the xenografts, while CEP192 overexpression in MGC-803 cells caused the opposite changes.
Conclusion: CEP192 overexpression is correlated with unfavorable outcomes of gastric cancer patients and promotes gastric cell proliferation by regulating the key proteins during G2/M phase transition.
目的: 探讨CEP192在胃癌中的表达情况及其预后价值，进一步研究其对胃癌细胞生物学功能的影响。
方法: 利用公共数据库探究CEP192在胃癌组织中的表达程度，通过免疫组织化学技术进一步验证CEP192在胃癌中的具体表达状态。通过构建Kaplan-Meier （K-M）生存曲线，探究CEP192蛋白表达与胃癌患者长期预后的关联性。同时，利用单因素和多因素Cox回归分析模型，深入分析影响胃癌患者根治术后5年生存率的风险因素。通过受试者工作特征（ROC）曲线分析评估CEP192表达水平在预测胃癌患者术后5年生存率的价值。生物信息学功能富集预测CEP192在胃癌发生发展中可能参与的生物学过程。采用慢病毒干扰及过表达CEP192，CCK-8法检测CEP192对胃癌细胞增殖能力的影响，免疫印迹法检测CEP192对胃癌细胞G2/M期关键蛋白PLK1、CDK1、Cyclin B1的影响。将慢病毒稳定转染的各组细胞接种于裸鼠背部皮下进行裸鼠成瘤实验，在体观察CEP192对小鼠体质量、瘤体大小及G2/M期关键蛋白的影响。
结果: CEP192在胃癌中高表达且与患者预后不良相关（P<0.05）。多因素Cox回归分析发现，CEP192高表达、CEA≥5 ng/mL、CA199≥37 IU/mL、T3-4期和N2-3期均为影响胃癌患者术后5年生存率的独立危险因素（P<0.05）。GO及REACTOME基因富集分析提示CEP192可能参与细胞周期等生物学过程，GSEA基因集富集分析结果显示CEP192对细胞周期过程呈现正向调控。CCK-8结果示干扰CEP192后MGC-803细胞的增殖能力减弱，过表达细胞增殖能力增强（P<0.05）。免疫印迹结果显示干扰CEP192后PLK1、CDK1、Cyclin B1蛋白表达水平下降，过表达呈上升趋势（P<0.05）。裸鼠皮下成瘤实验结果显示，与对照组相比，干扰CEP192小鼠体质量降低，肿瘤体积变小，PLK1、CDK1、Cyclin B1蛋白水平下调，过表达CEP192则呈现相反趋势（P<0.05）。
结论: CEP192在胃癌组织中高表达，与患者的不良预后相关，其可能通过调控G2/M期关键蛋白的表达影响肿瘤细胞恶性增殖。
Keywords: CEP192; cell cycle; gastric cancer; poor prognosis; proliferation.