High nuclear ABCG1 expression is a poor predictor for hepatocellular carcinoma patient survival.

BACKGROUND: ATP-binding cassette transporter G1 (ABCG1) regulates cellular cholesterol homeostasis and plays a significant role in tumor immunity. But, for hepatocellular carcinoma (HCC), the role of ABCG1 has not been investigated. Thus, the aim of this study was to evaluate the prognostic value and clinicopathological significance of ABCG1 in HCC. METHODS: One hundred and four adult patients with HCC were enrolled, and ABCG1 expression in paired HCC specimens was determined by immunohistochemistry. All these patients were stratified by ABCG1 expression, Kaplan-Meier analysis was used to compare the overall survival (OS) and recurrence-free survival (RFS), and Cox regression analysis was used to determine independent predictors of tumor recurrence. RESULTS: Upregulation of ABCG1 was observed in HCC samples compared to matched tumor-adjacent tissues. Patients with high nuclear ABCG1 expression had lower OS and RFS (P = 0.012 and P = 0.020, respectively). High nuclear ABCG1 expression was related to larger tumor size (P = 0.004) and tumor recurrence (P = 0.027). Although ABCG1 was expressed in the cytoplasm, cytosolic expression could not predict the outcome in patients with HCC. A new stratification pattern was established based on the heterogenous ABCG1 expression pattern: high risk (Highnucleus/Lowcytosol), moderate risk (Highnucleus/Highcytosol or Lownucleus/Lowcytosol), and low risk (Lownucleus/Highcytosol). This ABCG1-based risk stratification could distinguish the different OS and RFS in patients with HCC. Multivariate Cox regression analysis indicated that ABCG1 high risk was an independent predictor of poor RFS (P = 0.015). CONCLUSIONS: High nuclear ABCG1 expression indicates poor prognosis in patients with HCC. Asymmetric distribution of ABCG1 in the nucleus and cytoplasm may have an important role in tumor recurrence.

Alpha-fetoprotein and 18F-FDG standard uptake value predict tumor recurrence after liver transplantation for hepatocellular carcinoma with portal vein tumor thrombosis: Preliminary experience.

BACKGROUND: Portal vein tumor thrombosis (PVTT) is regarded as a contraindication for liver transplantation (LT) in hepatocellular carcinoma (HCC). However, some of these patients may have a favorable prognosis after LT. In this study, we evaluated the biological behavior of HCC with PVTT using tumor biomarker (alpha-fetoprotein, AFP) and 18F-FDG positron emission tomography (tumor standard uptake value) to identify a subset of patients who may be suitable for LT. METHODS: Seventy-five HCC-PVTT liver recipients transplanted during February 2016 and June 2018 were analyzed. Different pre-transplant prognostic factors were identified by univariate and multivariate analyses. PVTT status was identified following Vp classification (Vp1-Vp4). RESULTS: Three-year recurrence-free survival and overall survival rates were 40% and 65.4% in Vp2-Vp3 PVTT patients, 21.4% and 30.6% in Vp4 PVTT patients (P < 0.05). Total tumor diameter >8 cm, pre-transplant AFP level >1000 ng/mL and intrahepatic tumor maximal standard uptake value (SUVmax-tumor >5) were independent risk factors for HCC recurrence and overall survival after LT in Vp2-3 PVTT patients. Low risk patients were defined as total tumor diameter ≤8 cm; or if total tumor diameter more than 8 cm, with both pre-transplant AFP level less than 1000 ng/mL and intrahepatic tumor SUVmax less than 5, simultaneously. Twenty-two Vp2-3 PVTT HCC patients (46.8%) were identified as low risk patients, and their 3-year recurrence-free and overall survival rates were 67.6% and 95.2%, respectively. CONCLUSIONS: Patients with segmental or lobar PVTT and biologically favorable tumors defined by AFP and 18F-FDG SUVmax might be suitable for LT.