Association between expression of Cullin 4B and prognosis of patients after liver transplantation / 中华消化外科杂志

ABSTRACT

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) follow-up and survival;(3) prognostic factors analysis after liver transplantation;(4) association between expression of CUL4B and recurrence and metastasis of tumor after liver transplantation.Follow-up 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 (x)±s.The comparison between groups of count data was done using the chi-square test.The survival curve drawn using the Kaplan-Meier method,and the survival analysis was done by Log-rank 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 tissuesimmunohistochemistry staining showed that CUL4B was mainly expressed in the cytoplasm,with a powerful brownish-yellow staining.The high expression and low expression of CUL4B in HCC tissues were detected in 64 and 15 patients,respectively.(2) Follow-up and survival79 patients were followed up for 38-56 months,with an average time of 46 months.During the follow-up,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 3-year overall survival rates were respectively 86.84％ and 63.25％,and 1-and 3-year tumorfree survival rates were respectively 62.31％ and 51.27％.(3) Prognostic factors analysis after liver transplantation① Results of univariate analysis showed that preoperative alpha-fetoprotein (AFP),Child-Pugh score,maximum tumour dimension,capsular invasion,intravascular tumor thrombus,Edmonson pathological grading and expression of CUL4B were related factors affecting the 3-year 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 alpha-fetoprotein (AFP),Child-Pugh score,maximum tumour dimension,capsular invasion,intravascular tumor thrombus,Edmonson pathological grading and expression of CUL4B were related factors affecting the 3-year tumor-free 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％CI1.34-4.85,1.72-8.63,1.79-7.31,1.46-4.86,1.19-8.63,1.19-7.92,1.06-4.87,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 3-year overall survival rate of patients after liver transplantation for HCC [Odds ratio(OR) =3.43,3.69,2.81,95％CI1.16-6.02,1.96-9.38,1.04-9.63,P＜0.05].The maximum tumour dimension,intravascular tumor thrombus and expression of CUL4B were independent factors affecting the 3-year tumor-free survival rate of patients after liver transplantation for HCC (OR=2.25,4.72,2.74,95％C11.16-4.02,1.98-9.47,1.03-7.10,P＜ 0.05).The 3-year overall survival rate in patients with high-and low-expressions of CUL4B was respectively 66.7％ and 32.8％,with a statistically significant difference (x2 =5.69,P＜0.05).The 3-year tumor-free survival rate in patients with high-and low-expressions of CUL4B was respectively 73.3％ and 18.6％,with a statistically significant difference (x2 =4.63,P＜0.05).(4) Association between expression of CUL4B and recurrence and metastasis of tumor after liver transplantationresults 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.