Ying Tong

HIF1 regulates WSB‐1 expression to promote hypoxia‐induced chemoresistance in hepatocellular carcinoma cells

WSB‐1 is involved in DNA damage response by targeting homeodomain‐interacting protein kinase 2 (HIPK2) for ubiquitination and degradation. Here, we report that hypoxia significantly up‐regulates the expression of WSB‐1 in human hepatocellular carcinoma (HCC) cells. We also provide evidence that WSB‐1 is a target of hypoxia‐inducible factor 1 (HIF‐1). Silencing the expression of HIF‐1α in HCC cells by RNA interference abolishes hypoxia‐induced WSB‐1 expression. Using chromatin immunoprecipitation and luciferase reporter assays, we identified a HRE of the WSB‐1 gene. Moreover, silencing the expression of WSB‐1 by RNA interference rescues HIPK2 expression in hypoxic HCC cells and promotes etoposide‐induced cell death in hypoxic HCC cells. Taken together, these data shed light on the mechanisms underlying hypoxia‐induced chemoresistance in HCC cells.

Hepatitis B virus-associated intrahepatic cholangiocarcinoma: a malignancy of distinctive characteristics between hepatocellular carcinoma and intrahepatic cholangiocarcinoma

It has been a decade since hepatitis B virus infection was identified as an etiological factor for the development of intrahepatic cholangiocarcinoma (ICC). In recent years, several studies have elucidated the critical impact of hepatitis B virus in ICC that significantly influenced the clinicopathological characteristics of ICC patients with intrahepatic cholangiocarcinoma. Distinctive features of patients with hepatitis B virus-associated ICC included younger age, preponderance of male patients, frequent elevation of alpha-fetoprotein, and infrequent lymph node metastasis. Furthermore, several studies indicated that the presence of hepatitis B virus is a favorable prognostic factor in terms of overall survival and relapse-free survival. However, there are also a few studies demonstrating that hepatitis B virus negatively influenced or showed no significant association with survival outcomes of patients with ICC. At present, there are no consensus on diagnostic procedures and treatments for such population. Therefore, we elucidated current knowledge and recent identifications of HBV-associated ICC to clarify the impact of chronic HBV infection on patients with ICC and to precisely conduct diagnostic procedures and curative treatments for HBV-associated ICC.

Transarterial Chemoembolization: A Favorable Postoperative Management to Improve Prognosis of Hepatitis B Virus-associated Intrahepatic Cholangiocarcinoma after Surgical Resection

Background: There is no information regarding transarterial chemoembolization (TACE) as a postoperative management after hepatic resection for patients with hepatitis B virus (HBV)-associated intrahepatic cholangiocarcinoma (ICC). Methods: Forty-two patients with pathological confirmation of HBV-associated ICC were enrolled. Prognostic impact of the clinicopathological factors as well as postoperative TACE were evaluated. Computed tomography findings of HBV-associated ICC were assessed. Results: Tumor size of larger than 5 cm (hazard ratio [HR], 5.654; 95% confidence interval [CI], 1.175 to 27.204; P = 0.031), postoperative TACE (HR, 0.123; 95% CI, 0.023 to 0.643; P = 0.013), and lymph node metastasis (HR, 3.284; 95% CI, 1.236 to 8.724; P = 0.017) revealed to be independently associated with survival outcomes of patients with HBV-associated ICC. Application of TACE, as a postoperative management to control early local recurrence on the basis of hepatic arterial phase enhancement, significantly prolonged survival outcomes (1-yr, 88.9%; 3-yr, 77.8%; 5-yr, 66.7%), compared to the patients who did not receive TACE (1-yr, 63.6%; 3-yr, 30.8%; 5-yr, 13.0%). When analyzed according to the status of hepatic arterial phase, arterial phase enhancement demonstrated a favorable trend on prognosis of patients with HBV-associated ICC without statistical significance (HR, 0.435; 95% CI, 0.140 to 1.359; P = 0.141), and TACE independently improved overall survival of patients with arterial phase enhancement (HR, 0.105; 95% CI, 0.014 to 0.774; P = 0.027). Conclusions: Put together, our results indicate that postoperative TACE effectively improves prognosis of HBV-associated ICC with arterial phase enhancement in CT scans. Large-sized trials are required for our results to be applied in clinical medicine.

Application of a novel liquid biopsy in patients with hepatocellular carcinoma undergoing liver transplantation

Circulating tumor cells (CTCs) serves a primary function in metastasis and recurrence of hepatocellular carcinoma (HCC). In the present study, in order to evaluate the analytical performance and clinical value of the liquid biopsy-based platform, a novel integrated subtraction enrichment and immunostaining-fluorescence in situ hybridization (iFISH®) platform was applied to analyze CTCs in patients with HCC undergoing liver transplantation (LT). In total, 30 patients with HCC undergoing LT and 10 healthy volunteers were enrolled. CTCs in peripheral blood that were obtained from each patient prior to LT and 3 months thereafter were detected using the iFISH® platform, and CellSearch® system was performed for each subject for comparison. Using iFISH® and CellSearch®, the percentage of CTCs in patients with pre-operative HCC were 70.00% and 26.67%, respectively. CTCs counted using iFISH® (iFISH-CTCs) were increased compared with CellSearch® (Cellsearch-CTCs) (P<0.01). A significant decrease in iFISH-CTCs was observed 3 months following LT (3.04±0.93/7.5 to 1.0±0.53/7.5 ml, P<0.05). Furthermore, patients with lower preoperative iFISH-CTCs level (<5/7.5 ml) had markedly increased recurrence-free survival compared with iFISH-CTCs (>5/7.5 ml, 15 vs. 5.5 months; P<0.01. iFISH® platform exhibits an increased analytical sensitivity, and may be used as a dynamic monitoring tool for CTCs, and CTCs may be a good prognostic indicator for patients with HCC undergoing LT.

Prognostic Impact of Cirrhosis in Patients with Intrahepatic Cholangiocarcinoma following Hepatic Resection

Background Prognostic impact of cirrhosis in patients with intrahepatic cholangiocarcinoma (ICC) upon hepatic resection remains unclear due to lack of studies in the literature. Methods A total of 106 resected patients with ICC were reviewed, including 25 patients (23.6%) with cirrhosis and 81 noncirrhotic patients (76.4%). Subgroups of cirrhotic patients with and without hepatitis B virus (HBV) infection were studied. Results The impact of cirrhosis on the overall survival (OS) (hazard ratio [HR], 0.901; 95% confidence interval [CI], 0.510 to 1.592; P = 0.720) and the relapse-free survival (RFS) (HR, 0.889; 95% CI, 0.509 to 1.552; P = 0.678) revealed no statistical significance. Furthermore, HBV-associated cirrhotic patients and the other cirrhotic patients demonstrated no statistical difference on survival outcomes (1 yr OS, 60.0% versus 70.0%; 5 yr OS, 10.0% versus 0%; P = 0.744; 1 yr RFS, 53.3% versus 30.0%; 5 yr RFS, 10.0% versus 0%; P = 0.279). In patients with cirrhosis, tumor size larger than 5 cm was found to be the foremost factor that was independently associated with poor prognosis. Conclusion The presence of liver cirrhosis did not significantly affect prognosis of patients with ICC after resection. Downstaging modality may be in need for patients with ICC underlying cirrhosis, which remains to be validated in future studies.

Expression of VEGFR-3 in intrahepatic cholangiocarcinoma correlates with unfavorable prognosis through lymphangiogenesis

Background & aims: VEGFR-3 has been shown of great significance in lymph node metastasis and some malignancies, however, its expression in tumors and impact on outcome of intrahepatic cholangiocarcinoma (iCCA) remains unknown. The aim of this study was to assess the role of VEGFR-3 positive tumors for prognosis of iCCA and tumor-associated lymphangiogenesis. Methods: Clinicopathological features, prognostic factors and survival rate were analyzed to evaluate the influence of VEGFR-3 positive expression on prognosis of iCCA. In addition, tumor-associated lymphangiogenesis quantified as micro-lymphatic vessel density (MLVD) was assessed to explore the correlation between VEGFR-3 expression and lymph node metastasis for iCCA. Results: Patients with VEGFR-3 positive tumors had increased lymph node metastasis (p=0.025) and were more likely to suffer from tumor recurrence compared with VEGFR-3 negative tumors (p<0.001). VEGFR-3 expression in tumors was identified as an independent prognostic factor for both overall and recurrence-free survival in surgical resected patients with iCCA. In addition, higher MLVD was significantly associated with VEGFR-3 positive expression in tumors (p<0.001), which facilitate lymph node metastasis and significantly worse survival rates. Conclusions: Our study reveals that VEGFR-3 positive expression in tumors represents an independent prognostic factor for both overall and recurrence-free survival in hepatic resected patients with iCCA. VEGFR-3 positive tumors favor lymph node metastasis, tumor recurrence and worse outcomes through tumor-associated lymphangiogenesis.

Hepatocellular Carcinoma‐Associated Protein TD26 Interacts and Enhances Sterol Regulatory Element‐Binding Protein 1 Activity to Promote Tumor Cell Proliferation and Growth

Hepatocellular carcinoma (HCC) is a leading cause of cancer‐related death worldwide. Increased lipogenesis has been reported to play a critical role in HCC progression. However, the underlying mechanism contributing to lipogenesis increase in HCC remains elusive. Here, we show that HCC‐associated protein TD26 (TD26) was highly expressed in HCC tumor tissues compared to matched normal tissues. From the clinicopathologic analyses of two independent HCC cohorts, we demonstrate that TD26 expression was positively correlated with tumor size and was an independent predictor of overall survival (OS) and recurrence‐free survival (RFS) in HCC patients. Our metabolomics assays demonstrate that TD26 had no effect on glycometabolism, but significantly increased lipogenesis in HCC cells. In addition, our functional assays indicate that TD26 promoted HCC cell proliferation and tumor growth. We further demonstrate that TD26‐mediated increase in lipogenesis and tumor cell proliferation was SREBP1 dependent. Mechanistically, we demonstrate that, through its C‐terminus (amino acids [aa] from 121 to 198), TD26 interacted with the truncated nuclear sterol regulatory element‐binding protein 1 (SREBP1) form (nSREBP1), but not full‐length SREBP1 (flSREBP1), to block adenosine 5′‐monophosphate (AMP)‐activated protein kinase (AMPK)‐mediated inhibition on SREBP1 activity, resulting in increased lipogenesis, elevated tumor cell proliferation, and enhanced tumor progression. Conclusion: We propose that TD26 is a positive regulator on SREBP1 transactivity, and the interaction between TD26 and SREBP1 can serve as a potential therapeutic target for HCC treatment.

Metabolic modulation of acetaminophen-induced hepatotoxicity by osteopontin

Induction of osteopontin (OPN), a well-known pro-inflammatory molecule, has been observed in acetaminophen (APAP)-induced hepatotoxicity. However, the precise cell source for OPN induction and its role during APAP-induced hepatotoxicity has not been fully explored. By employing a hepatotoxic mouse model induced by APAP overdose, we demonstrate that both serum and hepatic OPN levels were significantly elevated in response to APAP treatment. Our in vivo and in vitro studies clearly indicated that the induced expression of hepatic OPN was mainly located in necrosis areas and produced by dying or dead hepatocytes. Functional experiments showed that OPN deficiency protected against the APAP-induced liver injury by inhibiting the toxic APAP metabolism via reducing the expression of the cytochrome P450 family 2 subfamily E member 1 (CYP2E1). Interestingly, this inhibition of CYP2E1 expression did not occur in unfasted Opn−/− mice, but was significant in fasted Opn−/− mice and maintained for 2 hours after APAP challenge in fasted Opn−/− mice. In addition, despite the early protective role of OPN deficiency on APAP-induced hepatotoxicity, OPN deficiency retarded injury resolution by sensitizing hepatocytes to apoptosis and impairing liver regeneration. Finally, we demonstrated that a siRNA-mediated transient hepatic Opn knockdown could sufficiently and significantly protect animals from APAP-induced hepatotoxicity and death. In conclusion, this study clearly defines the cell source of OPN induction in response to APAP treatment, provides a novel insight into the metabolic role of OPN to APAP overdose, and suggests an Opn-targeted therapeutic strategy for the treatment or prevention of APAP-induced hepatotoxicity.

Isolation of cancer-associated fibroblasts and its promotion to the progression of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma is a highly fatal tumor characterized by an abundant stromal environment. Cancer‐associated fibroblasts play key roles in tumor growth and invasiveness and have been regarded as a potential therapeutic target. This study was designed to isolate human primary cancer‐associated fibroblasts of intrahepatic cholangiocarcinoma to study tumor‐stroma interactions and to analyze the clinical relevance of alpha‐smooth muscle actin ‐positive cancer‐associated fibroblasts in patients with intrahepatic cholangiocarcinoma. The isolated cancer‐associated fibroblasts were positive for alpha‐smooth actin, fibroblast‐specific protein‐1, fibroblast activation protein, and PDGFR‐β. In addition, cancer‐associated fibroblasts were found to increase proliferation, migration, and invasion of cholangiocarcinoma cells in vitro and promote tumor growth of mice in vivo. Moreover, alpha‐smooth muscle actin‐positive expression of cancer‐associated fibroblasts predicted unfavorable prognosis in patients with intrahepatic cholangiocarcinoma and showed correlation with presence of lymph node metastasis. This study may provide a useful tool to investigate further effect of cancer‐associated fibroblasts on the molecular mechanism of cholangiocarcinoma cells as well as contribution of cancer‐associated fibroblasts in lymphangiogenesis and lymph node metastasis.

Risk factors and survival outcomes of biliary complications after adult-to-adult living donor liver transplantation

The objective of this study was to evaluate the risk factors and survival outcomes of biliary complications (BCs) after living donor liver transplantation (LDLT) based on our single-center experience. From 2007 to 2010, 112 adult patients were assessed. Forty-nine patients (43.8%) experienced at least one episode of BCs, including biliary stricture and bile leak, occurring in 37.5% and 16.1% of the patients, respectively. Multivariate analysis indicated that hepatic artery thrombosis (relative risk (RR), 5.692; 95% CI, 2.132 to 15.201; p < 0.001), a hepatic duct diameter of less than 3 mm (RR, 2.523; 95% CI, 1.295 to 4.914; p = 0.005), ductoplasty (RR, 2.175; 95% CI, 1.134 to 4.174; p = 0.018), and cytomegalovirus infection (RR, 4.452; 95% CI, 1.868 to 10.613; p = 0.001) were independent risk factors for the development of BCs. However, these factors and BCs showed no prominent impact on the overall survival (OS) and graft survival (GS). In addition, the patients who developed vascular complications demonstrated poor outcomes in terms of OS (five-year, 56.3% vs. 78.1%; p = 0.017), GS (five-year, 56.3% vs. 77.1%; p = 0.023), and BC-free survival (five-year, 25.0% vs. 63.5%; p = 0.007) compared with patients without vascular complications. In conclusion, BCs remain a common problem after LDLT, especially for patients using duct-to-duct anastomosis. Hepatic artery thrombosis, a short duct diameter, ductoplasty, and cytomegalovirus infection lead to an increased incidence of BCs. The occurrence of BCs manifested no significant influence on the long-term survival outcomes. However, our findings await verification through large-scale randomized studies regarding the risk factors for the development of BCs and their impact on the prognosis.