Cullin 4B蛋白与肝癌肝移植术后预后的关系

Association between expression of Cullin 4B and prognosis of patients after liver transplantation

目的：探讨Cullin 4B（CUL4B）蛋白表达水平对肝癌肝移植术后预后的影响。方法：采用回顾性病例对照研究方法。收集2014年1月1日至2015年6月30日中山大学附属第一医院收治的79例肝癌行肝移植患者的临床病理资料。收集患者的肝癌组织病理学标本，石蜡包埋切片，并行HE染色和免疫组织化学染色检测。观察指标：（1）肝癌组织中CUL4B蛋白的表达情况。（2）随访和生存情况。（3）肝癌肝移植术后预后因素分析。（4）CUL4B蛋白表达水平与肝癌肝移植术后肿瘤复发转移的相关性分析。采用电话和门诊方式进行随访，了解患者肿瘤复发、转移及生存情况。随访时间截至2018年6月。正态分布的计量资料以±s表示；计数资料组间比较采用χ^2检验。采用Kaplan-Meier法绘制生存曲线并计算生存率，Log-rank检验进行生存分析。单因素和多因素分析采用COX回归模型。相关性分析采用Pearson检验。结果：（1）肝癌组织中CUL4B蛋白的表达情况。免疫组织化学染色检测显示：肝癌组织中CUL4B蛋白主要表达于细胞质内，呈现为强棕黄色染色。79例患者CUL4B蛋白在肝癌组织中的表达情况：64例呈高表达，15例呈低表达。（2）随访和生存情况：79例患者术后均获得随访，随访时间为38～56个月，平均随访时间为46个月。79例患者随访期间，37例肿瘤无复发，42例肿瘤复发（肿瘤肝外转移32例、肿瘤肝内转移 10例）；36例生存，43例死亡；术后1、3年总体生存率分别为86.84%、63.25%，无瘤生存率分别为62.31%、51.27%。（3）肝癌肝移植术后预后因素分析。①单因素分析结果显示：术前AFP、术前ChildPugh评分、肿瘤最大径、包膜浸润、脉管内癌栓、肿瘤Edmonson病理学分级及CUL4B蛋白表达水平均是影响肝癌患者肝移植术后3年总体生存率的相关因素（风险比=2.17，3.36，3.66，2.43，2.19，3.36，2.84，95%可信区间：1.17～4.04，1.53～7.42，2.10～6.42，1.33～4.17，1.08～9.04，1.58～7.59，1.17～6.32，P〈0.05）。术前AFP、术前ChildPugh评分、肿瘤最大径、包膜浸润、脉管内癌栓、肿瘤Edmonson病理学分级及CUL4B蛋白表达水平均是影响肝癌患者肝移植术后3年无瘤生存率的相关因素（风险比=2.06，3.72，3.16，2.36，2.83，3.21，1.69，95%可信区间：1.34～4.85，1.72～8.63，1.79～7.31，1.46～4.86，1.19～8.63，1.19～7.92，1.06～4.87，P〈0.05）。②多因素分析结果显示：肿瘤最大径、脉管内癌栓、CUL4B蛋白表达水平是影响肝癌患者肝移植术后3年总体生存率的独立影响因素（比值比=3.43，3.69，2.81，95%可信区间：1.16～6.02，1.96～9.38，1.04～9.63，P〈0.05）。肿瘤最大径、脉管内癌栓、CUL4B蛋白表达水平是影响肝癌患者肝移植术后3年无瘤生存率的独立影响因素（比值比=2.25，4.72，2.74，95%可信区间：1.16～4.02，1.98～9.47，1.03～7.10，P〈0.05）。CUL4B蛋白高表达和低表达肝癌患者肝移植术后3年总体生存率分别为66.7%和32.8%，两者比较，差异有统计学意义（χ^2=5.69，P〈0.05）；CUL4B蛋白高表达和低表达肝癌患者肝移植术后3年无瘤生存率分别为73.3%和18.6%，两者比较，差异有统计学意义（χ^2=4.63，P〈0.05）。（4）CUL4B蛋白表达水平与肝癌肝移植术后肿瘤复发转移的相关性分析。Pearson检验相关性分析结果显示：CUL4B蛋白表达水平与肝移植术后肝癌复发转移明显相关（r=0.62，P〈0.05）。进一步分析显示：CUL4B蛋白表达水平与肝移植术后肿瘤肝外远处转移明显相关（r=0.84，P〈0.05）。结论：肝癌组织中CUL4B蛋白表达水平与肝癌肝移植术后肝癌复发相关，可作为肝癌肝移植患者肿瘤复发和远处转移的预测指标。

Objective：To investigate the effect of expression of Cullin 4B （CUL4B） on the prognosis of patients after liver transplantation for hepatocellular carcinoma （HCC）. Methods：The retrospective case-control study was conducted. The clinicopathological data of 79 patients who underwent liver transplantation for HCC in the First Affiliated Hospital of Sun Yat-sen University between January 1, 2014 and June 30, 2015 were collected. The specimens of HCC tissues were collected and embedded in paraffin, and then were detected by immunohistochemistry staining. Observation indicators： （1） expression of CUL4B in HCC tissues; （2） followup and survival; （3） prognostic factors analysis after liver transplantation; （4） association between expression of CUL4B and recurrence and metastasis of tumor after liver transplantation. Followup using outpatient examination and telephone interview was performed to detect tumor recurrence or metastasis and survival up to June 2018. Measurement data with normal distribution were represented as ±s. The comparison between groups of count data was done using the chisquare test. The survival curve drawn using the KaplanMeier method, and the survival analysis was done by Logrank test. The univariate and multivariate analysis were respectively done using the COX regression model. The association analysis was done using the Pearson test. Results：（1） Expression of CUL4B in HCC tissues： immunohistochemistry staining showed that CUL4B was mainly expressed in the cytoplasm, with a powerful brownishyellow staining. The high expression and low expression of CUL4B in HCC tissues were detected in 64 and 15 patients, respectively. （2） Followup and survival： 79 patients were followed up for 38-56 months, with an average time of 46 months. During the followup, 37 patients had no tumor recurrence and 42 had tumor recurrence （32 with tumor extrahepatic metastasis and 10 with intrahepatic metastasis）; 36 had survival and 43 died; the 1 and 3year overall survival rates were respectively 86.84% and 63.25%, and 1 and 3year tumorfree survival rates were respectively 62.31% and 51.27%. （3） Prognostic factors analysis after liver transplantation： ① Results of univariate analysis showed that preoperative alphafetoprotein （AFP）, ChildPugh score, maximum tumour dimension, capsular invasion, intravascular tumor thrombus, Edmonson pathological grading and expression of CUL4B were related factors affecting the 3year overall survival rate of patients after liver transplantation for HCC [Hazard Ratio （HR）=2.17, 3.36, 3.66, 2.43, 2.19, 3.36, 2.84, 95% confidence interval （CI）： 1.17-4.04, 1.53-7.42, 2.10-6.42, 1.33-4.17, 1.08-9.04, 1.58-7.59, 1.17-6.32, P〈0.05]. The preoperative alphafetoprotein （AFP）, ChildPugh score, maximum tumour dimension, capsular invasion, intravascular tumor thrombus, Edmonson pathological grading and expression of CUL4B were related factors affecting the 3year tumorfree survival rate of patients after liver transplantation for HCC （HR=2.06, 3.72, 3.16, 2.36, 2.83, 3.21, 1.69, 95%CI： 1.34-4.85, 1.72-8.63, 1.79-7.31, 1.46-4.86, 1.19-8.63, 1.19-7.92, 1.06-4.87, P〈0.05）. ② Results of multivariate analysis showed that maximum tumour dimension, intravascular tumor thrombus and expression of CUL4B were independent factors affecting the 3year overall survival rate of patients after liver transplantation for HCC [Odds ratio（OR）=3.43, 3.69, 2.81, 95%CI： 1.16-6.02, 1.96-9.38, 1.04-9.63, P〈0.05]. The maximum tumour dimension, intravascular tumor thrombus and expression of CUL4B were independent factors affecting the 3year tumorfree survival rate of patients after liver transplantation for HCC （OR=2.25, 4.72, 2.74, 95%CI： 1.16-4.02, 1.98-9.47, 1.03-7.10, P〈0.05）. The 3year overall survival rate in patients with high and lowexpressions of CUL4B was respectively 66.7% and 32.8%, with a statistically significant difference （χ^2=5.69, P〈0.05）. The 3year tumorfree survival rate in patients with high and lowexpressions of CUL4B was respectively 73.3% and 18.6%, with a statistically significant difference （χ^2=4.63, P〈0.05）. （4） Association between expression of CUL4B and recurrence and metastasis of tumor after liver transplantation： results of Pearson test showed that expression of CUL4B was significantly associated with HCC recurrence and metastasis after liver transplantation （r=0.62, P〈0.05）. The further analysis showed that expression of CUL4B was significantly associated with extrahepatic metastasis after liver transplantation （r=0.84, P〈0.05）. Conclusion：The expression of CUL4B is associated with HCC recurrence after liver transplantation, and it can be as a predictor for HCC recurrence and distant metastasis after liver transplantation.