Reduced N-cadherin expression is associated with metastatic potential and poor surgical outcomes of hepatocellular carcinoma

Background and Aim: N‐cadherin (N‐cad), one of the classic cadherins, has been reported to be involved in tumor metastasis in some types of tumors. This study aims to investigate the expression status of N‐cad in hepatocellular carcinoma (HCC) and the correlation between N‐cad expression and metastatic potential, as well as the surgical outcomes of HCC. Methods: N‐cad expression in HCC and adjacent liver tissues, as well as normal liver tissues, was studied by immunohistochemistry and Western blot, and the relationship between N‐cad expression and the clinicopathological features of HCC was evaluated. By using RNA interference technique, the correlation of N‐cad expression and metastatic potential was investigated by downregulating N‐cad expression in HCCLM3 cells, and the effects of N‐cad downregulation on cell aggregation, migration, and invasion were then analyzed. Furthermore, the correlation between N‐cad expression and the surgical outcomes of a cohort of HCC patients was analyzed. Results: In liver tissues, N‐cad was strongly expressed on cell–cell boundaries, whereas various reduced‐expression patterns were observed in tumors. Of 64 HCC, 34 (53%) tumors showed reduced N‐cad expression, compared with their adjacent liver tissues. The decreased expression of N‐cad was significantly correlated with poorer tumor differentiation (P = 0.001) and vascular invasion (P = 0.003). N‐cad knockdown in HCCLM3 cells resulted in decreased cell aggregation and increased cell migration and invasion. The decreased expression of N‐cad in HCC was significantly associated with shorter postoperative disease‐free survival (P = 0.039). Conclusions: N‐cad expression is decreased in HCC, and the downregulation of N‐cad is associated with the metastatic potential of HCC and poorer surgical prognosis.     

Aldehyde dehydrogenase 1 is associated with recurrence‐free survival but not stem cell‐like properties in hepatocellular carcinoma

Aim: It has been reported that aldehyde dehydrogenase 1 A1 (ALDH1) could be not only a normal stem cell marker but also a cancer stem cell marker. ALDH1 expression could be a predictor of poor prognosis in a wide range of cancers. However, the role of ALDH1 in hepatocellular carcinoma (HCC) remains unclear. Method: We conducted loss‐of‐function assays for ALDH1 by using short‐hairpin RNA in HCC cells and evaluated the correlation between ALDH1 expression and clinicopathological features based on immunohistochemical assessment of 49 primary HCC tissues. Results: Neither cell proliferation nor the anchorage‐independent sphere formation ability of HCC cells were altered after ALDH1 knockdown. Flow cytometric analyses revealed that ALDH1 knockdown showed no remarkable change in the proportion of epithelial cell adhesion molecule (EpCAM)⁺ tumor‐initiating cells. Although non‐tumor tissues in primary HCC samples diffusely and homogenously expressed ALDH1 at low levels, tumor tissues contained cells with high levels of ALDH1 expression at varying frequencies. Primary HCC samples were categorized as ALDH1‐high or ALDH1‐low based on the percentage of ALDH1‐overexpressing cells. ALDH1‐high HCC was characterized by low serum levels of α‐fetoprotein (P < 0.01) and well‐differentiated pathology (P = 0.03). Multivariate analysis showed that high ALDH1 expression was a favorable prognostic factor in recurrence‐free survival of HCC (P = 0.02). Conclusion: Our findings show that ALDH1 expression has little association with stem cell‐like features in HCC cells. ALDH1 might function as a differentiation marker rather than a stem cell marker in HCC.     

Overexpression of EphA2, MMP‐9, and MVD‐CD34 in hepatocellular carcinoma: Implications for tumor progression and prognosis

Aim: To investigate the expression of erythropoietin‐producing hepatocellular (Eph)A2 receptor, matrix metalloproteinase (MMP)‐9, and angiogenesis in hepatocellular carcinoma (HCC), in order to reveal their expression correlations with tumor invasion, metastasis, and prognosis. Methods: From January 2000 to June 2003, 129 specimens of resected tumors from the patients with HCC were obtained. Corresponding pericarcinomatous liver tissues were also obtained and selected as a control group. Expressions of EphA2, MMP‐9, and CD34 were detected with immunohistochemical staining. Microvascular density (MVD) was calculated with counting of CD34‐positive vascular endothelial cells. Results: The expressions of EphA2, MMP‐9, and MVD in the HCC tissues were significantly higher than those in the pericarcinomatous liver tissues (P < 0.01). Statistical analysis showed there were significant correlations between the expressions of EphA2, MMP‐9 and MVD in some classicclinicopathological parameters (i.e. tumor nodule, vein invasion, tumor, node, metastasis stages, extrahepatic metastasis; P < 0.05). The correlation between EphA2 and MMP‐9 expression was positive (r = 0.625, P = 0.011). Tumor MVD was closely associated with EphA2 (r = 0.281, P = 0.01) and MMP‐9 (r = 0.319, P < 0.01) expressions. In particular, EphA2, MMP‐9, and MVD expressions levels were found to be independent prognostic factors after HCC resection. Conclusions: Overexpressions of EphA2 and MMP‐9 relate to tumor progression, metastasis, and prognosis in HCC. The present study suggests that EphA2 is associated with key mediators of angiogenesis and invasion.     

Identification of two portal vein tumor thrombosis associated proteins in hepatocellular carcinoma: protein disulfide-isomerase A6 and apolipoprotein A-I

Background and Aim: Portal vein tumor thrombus (PVTT) is one of the factors that can affect prognosis and survival of hepatocellular carcinoma (HCC). In the present study, we aimed to find out some biomarkers associated with vascular invasion features of HCC with the method of comparative proteomic analysis. Methods: The proteins were extracted from a pair of HCC tissues with PVTT and without PVTT, and then separated by two‐dimensional polyacrylamide gel electrophoresis. Differentially expressed protein spots were identified by matrix assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS). Further analysis of two proteins were completed using real‐time fluorescence quantitative polymerase chain reaction and western‐blot in 40 HCC tissues with PVTT (n = 20) and without PVTT (n = 20). Results: Among 465 protein spots displayed on the gels, 33 unique proteins (> twofold change, P < 0.01) were identified, including 24 upregulated in HCC tissue without PVTT and nine upregulated in HCC tissue with PVTT. The real‐time fluorescence quantitative PCR showed no statistically significant difference between HCC tissues with PVTT and without PVTT for mRNA expressions of protein disulfide‐isomerase, A6 (PDI A6) (P = 0.137) and apolipoprotein A‐I (Apo A‐I) (P = 0.718). However, compared with HCC tissues without PVTT, protein expression of PDI A6 was higher in HCC tissues with PVTT (P < 0.001), while protein expression of Apo A‐I was lower in HCC tissues with PVTT (P = 0.012). Conclusions: PDI A6 and Apo A‐I are closely related to vascular invasion feature of HCC.     

Overexpression of galectin-1 is associated with poor prognosis in human hepatocellular carcinoma following resection

Background and Aim: The high expression of the galectin‐1 predicts poor patient outcome in several tumors. The aim of this study was to investigate its prognostic value in patients with hepatocellular carcinoma (HCC) after resection. Methods: Galectin‐1 and tumor‐infiltrating FoxP3⁺ regulatory T cells (Tregs) were validated by tissue microarrays from HCC patients (n = 386) and statistically assessed for correlations with the clinical profiles and the prognosis of the patients. Results: We found that galectin‐1, which was prevalently upregulated in HCC, was significantly associated with tumor invasive characteristics (such as vascular invasion, incomplete encapsulation, poor differentiation, multiple number, and large tumor size). Patients with high galectin‐1 expression had a significantly poorer tumor recurrence (P = 0.025) and overall survival (P = 0.021) than those with low galectin‐1 expression. Even in early‐stage disease, high galectin‐1 expression was also independently associated with shortened survival (P < 0.001) and increased tumor recurrence (P = 0.005). Multivariate Cox proportional hazards analysis showed that galectin‐1 was an independent marker for predicting the poor prognosis of HCC. The galectin‐1 level was positively related to the number of tumor‐infiltrating FoxP3⁺ Tregs (r = 0.416, P < 0.001), and their combination served as a better prognosticator. The postoperative tumor recurrence and survival of HCC patients with galectin‐1^high and FoxP3^high were significantly poorer than the other groups (both P < 0.001). Conclusions: Galectin‐1 might be a new prognostic factor for HCC after resection and could potentially be a high‐priority therapeutic target.     

Osteopontin,a single marker for predicting the prognosis of patients with tumor‐node‐metastasis stage I hepatocellular carcinoma after surgical resection

Background and Aim: Osteopontin (OPN) has been linked to clinical outcomes in several solid tumors. However, it has not been fully evaluated whether OPN could be used as a single marker for the prognosis of patients with hepatocellular carcinoma (HCC), particularly in patients of the tumor‐node‐metastasis (TNM) stage I. Methods: A total of 151 patients with HCC who underwent surgical resection were enrolled, including 112 patients of the TNM stage I. OPN expression was evaluated using immunohistochemistry in the tissue microarrays derived from these patients. Immunoreactivity was classified according to the percentage and intensity of staining: negative (?), weak (+) and strong (++). The impact of OPN expression on survival of patients was analyzed. Results: In total, 65.6% (99 of 151) of HCC tissues expressed OPN. Overall survival in patients of OPN (?) group was significantly higher than those of OPN (+) or OPN (++) group (P = 0.049 and P = 0.001). Interestingly, in patients of the TNM stage I, OPN expression was correlated with the early recurrence after surgical resection (P = 0.001). Multivariate analysis showed that OPN expression was an independent prognostic factor for overall survival and disease‐free survival in patients with the TNM stage I HCC (hazard ratio, 2.272, P = 0.014 and 1.982, P = 0.037). Conclusions: These results suggest that OPN is commonly expressed in HCC and is a useful marker for predicting the prognosis of patients with the TNM stage I HCC, contributing to determining which individual patient needs adjuvant therapy to prevent the early recurrence after surgical resection.     

Overexpression of lysine specific demethylase 1 predicts worse prognosis in primary hepatocellular carcinoma patients

AIM: To investigate the clinicopathological features and prognostic value of lysine specific demethylase 1 (LSD1) in hepatocellular carcinoma (HCC).METHODS: We examined LSD1 expression in 60 paired liver cancer tissues and adjacent noncancerous tissues by quantitative real time polymerase chain reaction (qRT-PCR) and Western blotting. In addition, we analyzed LSD1 expression in 198 HCC samples by immunohistochemistry. The relationship between LSD1 expression, clinicopathological features and patient survival was investigated.RESULTS: Immunohistochemistry, Western blotting, and qRT-PCR consistently confirmed LSD1 overexpression in HCC tissues compared to adjacent non-neoplastic tissues (P < 0.01). Additionally, immunostaining showed more LSD1-positive cells in the higher tumor stage (T3-4) and tumor grade (G3) than in the lower tumor stage (T1-2, P < 0.001) and tumor grade (G1-2, P < 0.001), respectively. Moreover, HCC patients with high LSD1 expression had significantly lower 5-year overall survival rates (P < 0.001) and lower 5-year disease-free survival rates (P < 0.001), respectively. A Cox proportional hazards model further demonstrated that LSD1 over-expression was an independent predictor of poor prognosis for both 5-year disease-free survival [hazards ratio (HR) = 1.426, 95%CI: 0.672-2.146, P < 0.001] and 5-year overall survival (HR = 2.456, 95%CI: 1.234-3.932, P < 0.001) in HCC.CONCLUSION: Our data suggest for the first time that the overexpression of LSD1 protein in HCC tissues indicates tumor progression and predicts poor prognosis.     

Clinical utility of serum fucosylated hemopexin in Japanese patients with hepatocellular carcinoma

Aim: Hepatocellular carcinoma (HCC) is a common clinical problem all over the world. Fucosylated hemopexin (Fuc-Hpx) is a newly reported glycoprotein for the diagnosis of HCC, however, its clinical implications are unclear. The aim of this study was to elucidate the clinical utility of Fuc-Hpx in Japanese patients with HCC. Methods: The sera from 331 HCC patients, 45 with liver cirrhosis (LC), 85 with chronic hepatitis (CH) and 22 healthy people were examined for the expression of Fuc-Hpx; the level was compared with clinical parameters as well as hemopexin (Hpx) expression. The expressions of Fuc-Hpx in 12 HCC tissues and corresponding adjacent non-cancerous liver tissues were also examined. Results: No correlation was observed between Hpx and Fuc-Hpx level. The median Fuc-Hpx levels in healthy people and CH, LC and HCC patients were 3.8, 3.7, 6.1 and 7.6 AU/mL, respectively (CH vs LC, P = 0.002; CH vs HCC, P < 0.001; LC vs HCC, P = 0.02). Multivariate analysis revealed that low albumin, low prothrombin time and the presence of HCC were significantly correlated with high Fuc-Hpx (P = 0.013, =0.001 and <0.001, respectively). Among the HCC patients, albumin was correlated with high Fuc-Hpx; however, none of the tumor factors, such as tumor size, tumor number and tumor stage, was correlated with Fuc-Hpx level. The expression of Fuc-Hpx in cancer tissue was not different from that in non-cancerous tissue. Conclusion: Fuc-Hpx is a valuable biomarker for HCC but it might be a marker for hypercarcinogenic liver rather than a marker for tumor-bearing liver.     

Expression of vascular endothelial growth factor-C in human hepatocellular carcinoma

Background/Aims: Vascular endothelial growth factor‐C (VEGF‐C) is thought to be an important factor in tumor angiogenesis/lymphangiogenesis, but its role in hepatocellular carcinoma (HCC) has not yet been fully investigated. Methods: We immunohistochemically examined VEGF‐C expression in surgically resected tissues of 90 HCC. Results: In the 78 HCC with a single histological grade, VEGF‐C expression was significantly stronger in poorly differentiated HCC than in well‐ (P = 0.003) or moderately differentiated HCC (P = 0.0002). A ‘nodule‐in‐nodule’ case presented VEGF‐A expression in the well‐differentiated component and VEGF‐C expression in the moderately–poorly differentiated component. According to nodular diameter, VEGF‐C expression was significantly higher in nodules of 3.0 cm or larger (P = 0.0263). Extrahepatic metastases seen in seven cases expressed VEGF‐C. In 20 of the 28 cases who were able to be followed up, the frequency of intrahepatic recurrence tended to be higher and extrahepatic metastasis was significantly higher in the cases who had VEGF‐C expression in the tumor casts of the intrahepatic portal/hepatic vein branches than other cases without the expression (P = 0.0139). Disease‐free survival time tended to be shorter in cases with VEGF‐C expression in tumor casts of the portal/hepatic vein than in those without VEGF‐C expression (P = 0.053; log–rank test). Conclusions: VEGF‐C expression is related to the progression of HCC, and VEGF‐C expression in tumor casts of the intrahepatic portal/hepatic vein is considered to be a factor indicating recurrence/metastasis sites.     

Expression of 8‐hydroxy‐2′‐deoxyguanosine in chronic liver disease and hepatocellular carcinoma

Abstract: Reactive oxygen species may be involved in the progression of chronic liver disease and the occurrence of hepatocellular carcinoma (HCC). To clarify whether clinicopathological findings in liver diseases are related to oxidative DNA damage, hepatic expression of the 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG) was examined in 75 liver disease patients, which included 32 chronic hepatitis (CH), 13 liver cirrhosis (LC) and 30 HCC patients. The CH patients had higher 8‐OHdG‐positive hepatocytes than LC (P<0.05). In CH and LC, the number of 8‐OHdG‐positive hepatocytes was correlated with alanine aminotransferase and asparate aminotransferase (P<0.01 and P<0.05, respectively). Of 30 HCC cases, 25 cases (83%) showed stronger immunoreactivity than non‐cancerous counterparts. The patients with poorly differentiated HCC had a larger tumor size and higher levels of AFP, and exhibited higher labeling indices of PCNA‐, TUNEL‐ and 8‐OHdG‐positive cells than those with well and moderately differentiated HCC. Our findings suggest that oxidative DNA damage is increased in association with necroinflammation in chronic liver disease and determination of 8‐OHdG is useful in assessing high‐grade malignancy in HCC.     

Intra‐arterial 5‐fluorouracil/interferon combination therapy for hepatocellular carcinoma with portal vein tumor thrombosis and extrahepatic metastases

Background and Aims: We investigated the efficacy of intra‐arterial 5‐fluorouracil (5‐FU) and systemic interferon (IFN)‐α (5‐FU‐IFN) in the treatment of hepatocellular carcinoma (HCC) with portal vein tumor thrombosis in the first branch or trunk (Vp3/4) and extrahepatic metastases. Methods: We examined 17 HCC patients with Vp3/4 and extrahepatic metastases (meta group) and 31 HCC patients with Vp3/4 (non‐meta group). Baseline intrahepatic tumor factors and the hepatic reserve were similar between groups. The extrahepatic metastases of the meta group were not considered prognostic factors. Following the administration of 5‐FU/IFN to all patients, we compared the survival rates, response, time to progression (TTP), and safety between groups. Results: For intrahepatic HCC, complete response, partial response, stable disease, progressive disease, and drop out were observed in no (0%), one (6%), seven (41%), nine (53%), and no (0%) patients of the meta group, and in five (16%), seven (23%), 13 (42%), five (16%) and one (3%) patient of the non‐meta group, respectively. The response rate was significantly lower in the meta group (6% vs 39%, P = 0.018). The median TTP of intrahepatic HCC and the median survival time were significantly shorter in the meta group than in the non‐meta group (1.6 vs 6.3 months, P = 0.0001, and 3.9 months vs 10.5 months, P < 0.0001, respectively). The multivariate analysis showed that the absence of extrahepatic metastases was a significant and independent determinant of both TTP of intrahepatic HCC (P < 0.001) and overall survival (P < 0.001). No patient died of extrahepatic HCC‐related disease. Conclusions: The efficacy of 5‐FU/IFN for advanced HCC with Vp3/4 and extrahepatic metastases was markedly limited.     

Hepatic arterial infusion chemotherapy using 5-fluorouracil and systemic interferon-α for advanced hepatocellular carcinoma in combination with or without three-dimensional conformal radiotherapy to venous tumor thrombosis in hepatic vein or inferior vena cava

Aim: We investigated the efficacy of hepatic arterial infusion chemotherapy (HAIC) using 5‐fluorouracil (5‐FU) and systemic interferon (IFN)‐α (HAIC‐5‐FU/IFN) for advanced hepatocellular carcinoma (HCC) with venous tumor thrombosis (VTT) in the hepatic vein trunk (Vv2) or inferior vena cava (Vv3). Methods: Thirty‐three patients with HCC/Vv2/3 underwent HAIC with 5‐FU (500 mg/body weight/day, into hepatic artery on days 1–5 on the first and second weeks) and IFN‐α (recombinant IFN‐α‐2b 3 000 000 U or natural IFN‐α 5 000 000 U, intramuscularly on days 1, 3 and 5 of each week). Three‐dimensional conformal radiotherapy (3D‐CRT) was used in combination with HAIC‐5‐FU/IFN in 14 of 33 patients to reduce VTT. Result: The median survival time (MST) was 7.9 months, and 1‐ and 2‐year survival rates were 30% and 20%, respectively. Evaluation of intrahepatic response after two cycles of HAIC‐5‐FU/IFN showed complete response (CR) in three (9%) and partial response (PR) in seven (21%), with an objective response rate of 30%. Multivariate analysis identified reduction of VTT (P = 0.0006), size of largest tumor (P = 0.013) and intrahepatic response CR/PR (P = 0.030) as determinants of survival. CR/PR correlated significantly with tumor liver occupying rate (P = 0.016) and hepatitis C virus Ab (P = 0.010). Reduction of VTT correlated significantly with radiotherapy (P = 0.021) and platelet count (P = 0.015). Radiotherapy‐related reduction in VTT significantly improved survival of 16 patients with Vv3 and non‐CR/PR response of HAIC‐5‐FU/IFN (P = 0.028). Conclusion: As for advanced HCC with VTT of Vv2/3, HAIC‐5‐FU/IFN responsive patients could obtain favorable survival. Despite ineffective HAIC‐5‐FU/IFN, the combination with effective radiotherapy to VTT might improve patients' prognosis.     

Outcomes after curative treatment for cryptogenic cirrhosis-associated hepatocellular carcinoma satisfying the Milan criteria

Background and Aim: The prognosis of cryptogenic cirrhosis‐associated hepatocellular carcinoma (CC‐HCC) was reported to be poor because many of them were discovered at the advanced stage. The aim of this study is to reveal the clinical features of early CC‐HCC. Methods: Consecutive 36 curatively treated CC‐HCC patients satisfying the Milan Criteria were compared with corresponding 211 HCV‐associated HCC (HCV‐HCC) patients. The clinical background, tumor recurrence rate, overall survival rate, and prognostic values of the patients were assessed. Results: The size of CC‐HCCs was larger than that of HCV‐HCCs (P = 0.01). The respective tumor recurrence rates at 1, 3, and 5 years were 11%, 32%, and 46% in the CC‐HCC, and 21%, 59%, and 81% in the HCV‐HCC. The respective overall survival rates at 1, 3, and 5 years were 94%, 85%, and 80% in the CC‐HCC, and 98%, 81%, and 61% in the HCV‐HCC. CC‐HCC patients had a lower tumor recurrence rate and a higher survival rate compared to the HCV‐HCC patients (P = 0.001 and P = 0.02, respectively). Via multivariate analysis, significant factors for high recurrence rate were number of HCCs (P = 0.02) and serum alpha fetoprotein levels (P = 0.03) in CC‐HCC, whereas multiple tumors (P < 0.001), large tumor size (P = 0.01), and high alanine aminotransferase (P = 0.04) in HCV‐HCC. The factor for survival was albumin in both groups. Conclusion: The size of CC‐HCC was larger than that of HCV‐HCC even in patients who received curative treatment; however, the risk for recurrence and the mortality of the patients with CC‐HCC was lower than those with HCV‐HCC.