Adjacent Normal Liver Tissues Research Articles

DEP domain containing 1 is a novel diagnostic marker and prognostic predictor for hepatocellular carcinoma.

This study was conducted to determine DEPDC1 expression in hepatocelluar carcinomas (HCCs) and to reveal its potential role in diagnosis and prognosis of affected patients. DEPDC1 expression at the mRNA level was detected by quantitative real-time PCR (qRT-PCR) in 205 cases of HCC and paired adjacent normal liver tissues, and by semi-quantitative RT-PCR in 20 cases. Survival curves were obtained by using Kaplan-Meier method and Log-rank test. Independent predictors associated with regard to disease free survival (DFS) and overall survival (OS) were identified using the Cox proportional hazard model. High DEPDC1 mRNA levels were detected in 144 out of 205 cases (70.24%) of HCC, significantly associated with clinicopathological parameters, including tumor size (≥4cm), alpha-fetoprotein (≥100ng/ml), B-C of BCLC stage and recurrence. Kaplan-Meier survival analysis revealed that HCC patients with high DEPDC1 expression had poor OS and DFS. Multivariate analysis demonstrated that high DEPDC1 expression was an independent predictor of OS (HR=1.651; 95% 95%CI, 1.041- 2.617; p=0.033) and DFS (HR=1.583; 95%CI, 1.01- 2.483; p=0.045). Our results indicate DEPDC1 might be a novel diagnostic marker and an independent prognostic predictor for HCC patients.

Abstract B78: Bone marrow-derived mesenchymal stem cells promote colorectal cancer progression through paracrine neuregulin 1/HER3 signaling

Abstract Objective: Bone marrow-derived mesenchymal stem cell (BM-MSC) migrate to primary tumors and drive tumor progression. This study aimed to identify the molecular mechanisms associated with these heterotypic cellular interactions and analyse their relevance in colorectal cancer (CRC). Design: Paracrine interactions of BM-MSC and tumor-derived mesenchymal cells (T-MC) with CRC cells were studied using collagen invasion assays, cell counts, flow cytometric cell-cycle analysis and tumor xenograft models. The role of neuregulin 1 (NRG1) and the human epidermal growth factor receptor (HER) family pathways were investigated using tyrosine kinase assays, mass spectrometry, pharmacological inhibition, antibody-mediated neutralisation and RNA interference. Transmembrane NRG1 (tNRG1), HER2 and HER3 expression was analysed in primary CRCs (n = 54), adjacent normal colorectal tissues (n = 4), liver metastases (n = 3) and adjacent normal liver tissues (n = 3) by immunohistochemistry. Results: BM-MSC and T-MC stimulate invasion, survival and tumorigenesis of CRCs through release of soluble NRG1, activating the HER2/HER3-dependent PI3K/AKT signaling cascade in CRC cells. Mesenchymal cells in primary CRCs demonstrate high tNRG1 expression. HER2 and HER3 show membrane localization in cancer cells of CRC tissue. High stromal tNRG1 expression is significantly associated with advanced UICC stage (P = .005) and invasion depth (P = .04) and decreased 5-year progression-free-survival (PFS) (P = .01). Conclusion: Paracrine NRG1/HER3 signals initiated by BM-MSC and T-MC promote CRC cell progression, and high tNRG1 expression is associated with poor prognosis. Citation Format: Olivier De Wever, Astrid de Boeck. Bone marrow-derived mesenchymal stem cells promote colorectal cancer progression through paracrine neuregulin 1/HER3 signaling. [abstract]. In: Abstracts: AACR Special Conference on Cellular Heterogeneity in the Tumor Microenvironment; 2014 Feb 26-Mar 1; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(1 Suppl):Abstract nr B78. doi:10.1158/1538-7445.CHTME14-B78

Low Expression of Polo-like Kinase 1 is Associated with Poor Prognosis in Liver Cancer

Aim: To determine the expression level of polo-like kinase 1 (PLK1) in liver cancer specimens and assess its prognostic value. Methods: Postconsent, 85 liver cancer specimens and their paired adjacent normal liver tissues were obtained during hepatectomy. The samples were clinicopathologically characterized, followed by immunohistochemical staining to determine the expression levels of PLK1. The study subjects were followed up for 2–117 months (the median follow-up period was 26 months) to assess their overall survival time. Results: Cancer specimens demonstrated significantly lower expressions of PLK1 than normal hepatocytes (76% vs . 95%, respectively, P 5 cm, P = 0.045, χ 2 test), liver capsule invasion ( P = 0.004, χ 2 test), and American Joint Committee on Cancer Stage IV ( P = 0.007, χ 2 test). The survival time of PLK1 negative subjects was significantly shorter than that of PLK1 positive cases ( P = 0.041, log-rank test). Conclusion: Downregulation of PLK1 expression demonstrates a strong correlation with liver cancer and may serve as a critical indicator of poor prognosis of the disease.

MicroRNA-1 promotes apoptosis of hepatocarcinoma cells by targeting apoptosis inhibitor-5 (API-5)

Although microRNA-1 (miR-1) is a known liver cancer suppressor, the role of miR-1 in apoptosis of hepatoma cells has remained largely unknown. Our study shows that ectopic miR-1 overexpression induced apoptosis of liver hepatocellular carcinoma (HepG2) cells. Apoptosis inhibitor 5 (API-5) was found to be a potential regulator of miR-1 induced apoptosis, using a bioinformatics approach. Furthermore, an inverse relationship between miR-1 and API-5 expression was observed in human liver cancer tissues and adjacent normal liver tissues. Negative regulation of API-5 expression by miR-1 was demonstrated to promote apoptosis of HepG2 cells. Our study provides a novel regulatory mechanism of miR-1 in the apoptosis of hepatoma cells.

Lesion human leukocyte antigen-F expression is associated with a poor prognosis in patients with hepatocellular carcinoma.

Human leukocyte antigen (HLA)-F, a non-classical HLA-class I molecule, has attracted attention as an important immunosuppressive molecule in recent years, although the clinical relevance of HLA-F expression in cancer patients remains unclear. In the present study, HLA-F expression in 90 primary hepatocellular carcinoma (HCC) lesions and 55 corresponding adjacent normal liver tissues was analyzed by immunohistochemistry, and the associations between HLA-F expression and clinicopathological parameters and patient survival times were analyzed. Positive HLA-F expression was observed in 47.8% (43/90) of the HCC lesions and in 10.9% (6/55) of the normal liver tissues. HLA-F expression in HCC lesions was significantly correlated with patient gender (P=0.02), and venous or lymphatic invasion (P=0.02). Patients who were HLA-F-positive had worse survival times than those who were HLA-F-negative (P=0.04). The mean overall survival times for HLA-F-negative and -positive patients were 44.2 months [95% confidence interval (CI), 37.7–50.7] and 33.0 months (95% CI, 25.1–40.8), respectively. Multivariate analysis revealed that HLA-F was an independent prognostic factor for HCC patients with a hazard ratio of 2.1 (95% CI, 1.0–4.4). In conclusion, the present study demonstrated that HLA-F expression was associated with poor survival in HCC patients, and is correlated with tumor cell invasion and metastasis.

736P - Identification of Intragenic Methylation in the Tusc1 Gene As a Novel Prognostic Marker of Hepatocellular Carcinoma

ABSTRACT Aim: Patients with hepatocellular carcinoma (HCC) have a poor prognosis, and novel molecular targets for treating recurrence and progression of the disease along with associated biomarkers are urgently required. In the present study, expression and the regulatory mechanism of TUSC1 (tumor suppressor candidate 1) were investigated to determine if it is a candidate tumor suppressor gene for HCC, which shows repressed transcription that involves aberrant DNA methylation. Methods: TUSC1 mRNA expression levels in HCC cell lines and 94 pairs of surgical specimens were determined using quantitative real-time reverse transcription polymerase chain reaction assay. Methylation status of HCC cell lines and clinical samples were analyzed to investigate the regulatory mechanism of TUSC1 transcription and the relationship between the methylation status of the TUSC1 gene and clinicopathological factors. The expression and distribution of the TUSC1 protein in liver tissues were determined using immunohistochemistry. Results: A majority of HCC cell lines (89%) and surgical specimens (84%) demonstrated reduced expression levels of TUSC1 mRNA compared with paired non-cancerous liver tissues. The mean mRNA expression level in HCC was significantly lower than in corresponding non-cancerous liver. In contrast, no significant difference was found in TUSC1 mRNA expression level between adjacent normal and cirrhotic liver tissue from HCC patients. The TUSC1 protein expression pattern in HCC and liver tissues was consistent with TUSC1 mRNA expression. Twenty-nine (31%) of 94 patients showed intragenic hypermethylation of the TUSC1 gene in HCC, and hypermethylation was significantly associated with advanced pathological stage. Subsequently, patients with hypermethylation of TUSC1 gene had a significantly poorer prognosis than patients without hypermethylation. Conclusions: Our results suggest that TUSC1 is a candidate tumor suppressor gene and intragenic hypermethylation is one of the suppressive mechanisms that regulate TUSC1 transcription in HCC. Intragenic methylation of the TUSC1 gene may serve as a novel prognostic marker of HCC. Disclosure: All authors have declared no conflicts of interest.

Activation of RAS/ERK alone is insufficient to inhibit RXRα function and deplete retinoic acid in hepatocytes

Activation of RAS/ERK signaling pathway, depletion of retinoid, and phosphorylation of retinoid X receptor alpha (RXRα) are frequent events found in liver tumors and thought to play important roles in hepatic tumorigenesis. However, the relationships among them still remained to be elucidated. By exploring the transgenic mouse model of hepatic tumorigenesis induced by liver-specific expression of H-ras12V oncogene, the activation of RAS/ERK, the mRNA expression levels of retinoid metabolism-related genes, the contents of retinoid metabolites, and phosphorylation of RXRα were determined. RAS/ERK signaling pathway was gradually and significantly activated in hepatic tumor adjacent normal liver tissues (P) and hepatic tumor tissues (T) of H-ras12V transgenic mice compared with normal liver tissues (Wt) of wild type mice. On the contrary, the mRNA expression levels of retinoid metabolism-related genes were significantly reduced in P and T compared with Wt. Interestingly, the retinoid metabolites 9-cis-retinoic acid (9cRA) and all-trans-retinoic acid (atRA), the well known ligands for nuclear transcription factor RXR and retinoic acid receptor (RAR), were significantly decreased only in T compared with Wt and P, although the oxidized polar metabolite of atRA, 4-keto-all-trans-retinoic-acid (4-keto-RA) was significantly decreased in both P and T compared with Wt. To our surprise, the functions of RXRα were significantly blocked only in T compared with Wt and P. Namely, the total protein levels of RXRα were significantly reduced and the phosphorylation levels of RXRα were significantly increased only in T compared with Wt and P. Treatment of H-ras12V transgenic mice at 5-week-old or 5-month-old with atRA had no effect on the prevention of tumorigenesis or cure of developed nodules in liver. These events imply that the depletion of 9cRA and atRA and the inhibition of RXRα function in hepatic tumors involve more complex mechanisms besides the activation of RAS/ERK pathway.

MiR-21 expression predicts prognosis in hepatocellular carcinoma

The aim was to investigate the expression level of miR-21 in HCC tissues and its prognostic value among Asian population. In the present study, expression of miR-21 was evaluated by qRT- PCR in tumor and adjacent non-neoplastic tissues in 119 HCC patients. The association of miR-21 expression with clinicopathological factors and the prognosis of HCC patients was also analyzed. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model. We found that miR-21 expression was significantly higher in HCC tissues compared with normal adjacent liver tissues (P<0.0001). The 5-year overall survival (OS) of high miR-21 expression group was significantly shorter than that of low miR-21 expression group (40.2% vs. 70.7%; P=0.007). Moreover, the 5-year disease-free survival (DFS) of high miR-21 expression group was also significantly shorter than that of low miR-21 expression group (17.4% vs. 57.3%; P=0.001). Furthermore, in a multivariate Cox model, we found that miR-21 expression was an independent poor prognostic factor for both 5-year OS (hazards ratio [HR]=3.189, 95% confidence interval [CI]=1.911-10.012, P=0.03) and 5-year DFS (HR=5.897, CI=3.009-13.763, P<0.001) in HCC. The results of the present study suggested miR-21 expression level could be a novel potential biomarker for HCC prognosis.

High expression of microRNA-130b correlates with poor prognosis of patients with hepatocellular carcinoma.

BackgroundWhether microRNA-130b(miR-130b) can serve as a prognostic biomarker of hepatocellular carcinoma (HCC) has not been investigated. In the present study, we investigated the feasibility of miR-130b as a novel prognostic biomarker for HCC.MethodsWe retrospectively investigated 97 patients diagnosed with HCC who underwent routine curative surgery between May 2007 and July 2012. miR-130b expression in HCC tissues and paired normal adjacent liver tissues was measured by reverse transcription and real-time PCR (RT-PCR). Survival curves were plotted using the Kaplan-Meier method and differences in survival rates were analyzed using the log-rank test.ResultsmiR-130b expression level was significantly higher in HCC tissues compared with normal adjacent liver tissues (P < 0.0001). The 5-year overall survival (OS) of high miR-130b expression group was significantly shorter than that of low miR-130b expression group (43.6% vs. 71.5%; P = 0.022). Moreover, the 5-year disease-free survival (DFS) of high miR-130b expression group was also significantly shorter than that of low miR-130b expression group (25.9% vs. 63.9%; P = 0.012). In a multivariate Cox model, we found that miR-130b expression was an independent prognostic factor for both 5-year OS (hazards ratio [HR] = 2.523, 95% confidence interval [CI] = 1.024-7.901, P = 0.011) and 5-year DFS (HR = 4.003, CI = 1.578-7.899, P = 0.005) in HCC.ConclusionThe results indicated that high expression of microRNA-130b was correlated with significant characteristics of patients with HCC, and it might be useful as a novel prognostic biomarker for HCC.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_160

MiR-506 suppresses proliferation of hepatoma cells through targeting YAP mRNA 3'UTR.

MiR-506 is a miRNA involved in carcinogenesis of several kinds of cancer. In this study, we explored whether miR-506 played a critical role in hepatocellular carcinoma (HCC). Twenty HCC and adjacent normal liver tissue samples were collected. Human hepatoma cell lines HepG2 and H7402 were used for in vitro studies. The expression of miR-506 and transcriptional co-activator YAP was examined using qRT-PCR. Western blot analysis was used to measure the expression of YAP and its target genes. Luciferase reporter gene assay was used to identify YAP as a target gene of miR-506. MTT and EdU assays were carried out for functional analysis. The expression of miR-506 was significantly lower in HCC than in adjacent normal liver tissues. Bioinformatics analysis revealed that YAP mRNA might be one of the targets of miR-506, and miR-506 in HCC tissues was found to be negatively correlated with YAP (r=-0.605). In both HepG2 and H7402 cells, miR-506 dose-dependently down-regulated YAP and its target genes c-Myc and the connective tissue growth factor (CTGF). Luciferase reporter gene assays demonstrated that miR-506 targeted the wild type 3'UTR of YAP mRNA, but not a 3'UTR with a mutant seed site. Furthermore, miR-506 significantly inhibited the proliferation of HepG2 and H7402 cells, while anti-miR-506 enhanced the cell proliferation, which was blocked by YAP siRNA. MiR-506 suppresses the proliferation of hepatoma cells by targeting YAP mRNA.

Could metabolic syndrome lead to hepatocarcinoma via non-alcoholic fatty liver disease?

It was estimated that from 2002 to 2008 the risk of developing cancer increased a quarter-fold in men and two-fold in women due to excessive BMI. Obesity, metabolic syndrome and type 2 diabetes mellitus are strictly related and are key pathogenetic factors of non-alcoholic fatty liver disease (NAFLD), the most frequent liver disease worldwide. The most important consequence of the "metabolic epidemics" is the probable rise in the incidence of hepatocarcinoma (HCC), and NAFLD is the major causative factor. Adipose tissue is not merely a storage organ where lipids are preserved as an energy source. It is an active organ with important endocrine, paracrine, and autocrine actions in addition to immune functions. Adipocytes produce a wide range of hormones, cytokines, and growth factors that can act locally in the adipose tissue microenvironment and systemically. In this article, the main roles of insulin growth factor (IGF)-1 and IGF-2 are discussed. The role of IGF-2 is not only confined to HCC, but it may also act in early hepato-carcinogenesis, as pre-neoplastic lesions express IGF-2 mRNA. IGF-1 and IGF-2 interact with specific receptors (IGF-1R and IGF-2R). IGF-1R is over-expressed in in vitro and in animal models of HCC and it was demonstrated that IGF ligands exerted their effects on HCC cells through IGF-1R and that it was involved in the degeneration of pre-neoplastic lesions via an increase in their mitotic activity. Both IGF-2R and TGF β, a growth inhibitor, levels are reduced in human HCC compared with adjacent normal liver tissues. Another key mechanism involves peroxisome proliferator-activated receptor (PPAR)γ. In in vitro studies, PPARγ inhibited various carcinomas including HCC, most probably by regulating apoptosis via the p21, p53 and p27 pathways. Finally, as a clinical consequence, to improve survival, efforts to achieve a "healthier diet" should be promoted by physicians and politicians.

The expression of microRNA-200a and its clinical significance in hepatic cancer tissues

Objective To determine the expression of microRNA-200a (miR-200a) in hepatic cancer tissues and its clinical significance.Methods The levels of expression of miR-200a in hepatic cancer cell lines,and in 58 cases of hepatic cancer and their adjacent normal liver tissues were detected by real time reverse transcription polymerase chain reaction(RT-PCR).The relations of the levels of miR-200a expression with clinicopathologic features were analyzed.Results RT-PCR revealed that the expression of miR-200a was down regulated in hepatic cancer cell lines and hepatic cancer tissues.The expression of miR200a was associated with tumor invasiveness and metastasis in patients with hepatic cancer.The expression of miR-200a in patients with tumor invasiveness and metastasis was significantly lower than those without (P ＜ 0.05).There was no significant difference with regard to sex,age,hepatitis status,tumor size,TNM staging and the level of AFP (all P ＞ 0.05).Conclusion The expression of miR-200a was downregulated in hepatic cancer tissue.There was a significant relation to tumor invasiveness and metastasis. Key words: Hepatic cancer tissues; Ribonucleic acid, microRNA-200a; Invasiveness and metastasis

High KIF18A expression correlates with unfavorable prognosis in primary hepatocellular carcinoma.

This study aimed to investigate KIF18A expression in hepatocellular carcinoma (HCC) and to determine the possibility of KIF18A expression being a biomarker in HCC diagnosis or being an independent predictor of disease-free survival (DFS) and overall survival (OS) in HCC patients underwent surgical resection. KIF18AmRNA was detected in 216 cases of HCC tissues by quantitative real-time PCR (qRT-PCR) and in 20 cases of HCC tissues by semi-quantitative RT-PCR. KIF18A protein was determined in 32 cases of HCC tissues by immunohistochemistry (IHC). The survival probability was analyzed by Kaplan-Meier method, and survival curves between groups were obtained by using the log-rank test. Independent predictors associated with DFS were analyzed with Stepwise Cox proportional hazard models. High KIF18A mRNA level was detected in 154 out of 216 (71.3%) cases of HCC. The positive rate of KIF18A expression was significantly higher in liver cancer tissues than that in adjacent normal liver tissues (ANLT) from HCC patients [65.6% (21 of 32) vs. 25.0% (8 of 32), P=0.001]. The KIF18A expression level had positive relevance to the alpha-fetoprotein (AFP) (≥ 200 ng/ml), tumor size (≥ 5 cm), clinical tumor-node-metastasis (TNM) stage and portal vein tumor thrombus (PVTT) in HCC (all P <0.05). A survival analysis indicated that HCC patients with higher KIF18A expression had a significantly shorter DFS and OS after resection. A multivariate analysis suggested that KIF18A upregualtion was an independent factor for DFS [hazard risk (HR)=1.602; 95% confidence interval (CI), 1.029-2.579; P=0.031] and OS (HR=1.682; 95% CI, 1.089-2.600; P=0.019). KIF18A might be a biomarker for HCC diagnosis and an independent predictor of DFS and OS after surgical resection.

Th22 cells are associated with hepatocellular carcinoma development and progression.

IL-22-producing CD4(+) T helper cells (Th22 cells) have been identified as major inducers of tissue inflammation and immune responses. Currently, no previous study explored the role of Th22 cells in the pathogenesis of hepatocellular carcinoma (HCC). The study aimed to determine the biological function of Th22 cells and its effector IL-22 in HCC patients. Forty-five HCC patients and 19 healthy controls were recruited and their peripheral blood was collected. The fresh HCC tissues, adjacent HCC tissues and ten normal liver tissues were also collected. Flow cytometry analysis was used to determine the frequencies of circulating Th22 cells and Th17 cells. Serum IL-22 levels were tested by enzyme-linked immunosorbent assay (ELISA). Immunohistochemical staining and real-time polymerase chain reaction (PCR) were used to detect IL-22 protein and mRNA in tissues specimens, respectively. Circulating Th22 cells, Th17 cells and serum IL-22 levels were significantly elevated in HCC patients compared with those of healthy controls (P<0.001). Th22 cells were showed to be positively correlated with IL-22 in HCC patients (P<0.05), but not in healthy controls. No significant differences were found in HCC patients with HBeAg positivity or negativity in term of Th22 cells and serum IL-22 levels. The expression of IL-22 protein and mRNA was highest in HCC tissues, followed by adjacent HCC tissues and normal liver tissues. Furthermore, Th22 cells, serum IL-22 levels and IL-22 mRNA were elevated at stage III-IV compared with stage I-II of HCC (P<0.05). Elevation of circulating Th22 cells and IL-22 may be implicated in the pathogenesis of HCC, and potentially be cellular targets for therapeutic intervention.

Pancreatic adenocarcinoma: a pilot study of quantitative perfusion and diffusion-weighted breath-hold magnetic resonance imaging

To confirm the feasibility of breath-hold DCE-MRI and DWI at 3T to obtain the intra-abdominal quantitative physiologic parameters, K(trans), k ep, and ADC, in patients with untreated pancreatic ductal adenocarcinomas. Diffusion-weighted single-shot echo-planar imaging (DW-SS-EPI) and dynamic contrast-enhanced (DCE) MRI were used for 16 patients with newly diagnosed biopsy-proven pancreatic ductal adenocarcinomas. K(trans), k ep, and apparent diffusion coefficient (ADC) values of pancreatic tumors, non-tumor adjacent pancreatic parenchyma (NAP), liver metastases, and normal liver tissues were quantitated and statistically compared. Fourteen patients were able to adequately hold their breath for DCE-MRI, and 15 patients for DW-SS-EPI. Four patients had liver metastases within the 6 cm of Z axis coverage centered on the pancreatic primary tumors. K(trans) values (10(-3) min(-1)) of primary pancreatic tumors, NAP, liver metastases, and normal liver tissues were 7.3 ± 4.2 (mean ± SD), 25.8 ± 14.9, 8.1 ± 5.9, and 45.1 ± 15.6, respectively, k ep values (10(-2) min(-1)) were 3.0 ± 0.9, 7.4 ± 3.1, 5.2 ± 2.0, and 12.1 ± 2.8, respectively, and ADC values (10(-3) mm(2)/s) were 1.3 ± 0.2, 1.6 ± 0.3, 1.1 ± 0.1, and 1.3 ± 0.1, respectively. K(trans), k ep, and ADC values of primary pancreatic tumors were significantly lower than those of NAP (p < 0.05), while K(trans) and k ep values of liver metastases were significantly lower than those of normal liver tissues (p < 0.05). 3T breath-hold quantitative physiologic MRI is a feasible technique that can be applied to a majority of patients with pancreatic adenocarcinomas.

Activated macrophages promote Wnt/β-catenin signaling in cholangiocarcinoma cells

The Wnt/β-catenin signaling pathway is pathologically activated in cholangiocarcinoma (CCA). Here, we determined the expression profile as well as biological role of activated Wnt/β-catenin signaling in CCA. The quantitative reverse transcription polymerase chain reaction demonstrated that Wnt3a, Wnt5a, and Wnt7b mRNA were significantly higher in CCA tissues than adjacent non-tumor tissues and normal liver tissues. Immunohistochemical staining revealed that Wnt3a, Wnt5a, and Wnt7b were positive in 92.1, 76.3, and 100 % of 38 CCA tissues studied. It was noted that Wnt3 had a low expression in tumor cells, whereas a high expression was mainly found in inflammatory cells. Interestingly, a high expression level of Wnt5a was significantly correlated to poor survival of CCA patients (P=0.009). Membrane localization of β-catenin was reduced in the tumors compared to normal bile duct epithelia, and we also found that 73.7 % of CCA cases showed the cytoplasmic localization. Inflammation is known to be a risk factor for CCA development, and we tested whether this might induce Wnt/β-catenin signaling. We found that lipopolysaccharides (LPS) elevated the expression of Wnt3 both mRNA and protein levels in the macrophage cell line. Additionally, the conditioned media taken from LPS-induced activated macrophage culture promoted β-catenin accumulation in CCA cells. Furthermore, transient suppression of β-catenin by siRNA significantly induced growth inhibition of CCA cells, concurrently with decreasing cyclin D1 protein level. In conclusion, the present study reports the abundant expression of Wnt protein family and β-catenin in CCA as well as the effect of inflammatory condition on Wnt/β-catenin activation in CCA cells. Importantly, abrogation of β-catenin expression caused significant CCA cell growth inhibition. Thus, the Wnt/β-catenin signaling pathway may contribute to CCA cell proliferation and hence may serve as a prognostic marker for CCA progression and provide a potential target for CCA therapy.

Serum anti-Ku86: a potential biomarker for early detection of hepatocellular carcinoma

To investigate the clinical value of serum anti-Ku86 in early detection of hepatocellular carcinoma (HCC). Expression levels of Ku86 protein in HCC and adjacent normal liver tissues were detected by Western blotting. Serum anti-Ku86 level in 83 patients with early HCC and 124 patients with liver cirrhosis were detected by enzyme-linked immunosorbent assay (ELISA). Chemiluminescence was used to measure the serum level of α-fetoprotein (AFP). Expression of Ku86 protein in HCC was increased when compared with the adjacent normal liver tissues (0.21 ± 0.05 vs. 0.08 ± 0.02, P < 0.01). Serum anti-Ku86 level was significantly elevated in HCC patients compared with that in liver cirrhosis patients (0.47 ± 0.22 vs. 0.22 ± 0.06 Abs at 450 nm, P < 0.01), but there was no significant difference between HBV infection and HCV infection in HCC patients (0.51 ± 0.19 vs. 0.47 ± 0.24, P = 0.267). Of note, serum anti-Ku86 level was significantly decreased after surgical resection of the tumors in the 30 HCC cases tested (P < 0.01). The results of ROC analysis indicated a better performance of anti-Ku86 (0.857) than AFP (0.739) for early detection of HCC. In 83 HCC patients, the positive rate of anti-Ku86 was 61.4% (51/83), significantly higher than that of the AFP positive rate (27.7%, 23/83). The anti-Ku86 level was positive in 37 of 60 HCC cases with negative AFP. Combination assay of AFP and anti-Ku86 could detect 60 of 83 HCC cases (72.3%, 60/83). There was no significant correlation of anti-Ku86 and AFP (r = 0.156, P = 0.161). Serum anti-Ku86 level is significantly elevated and is not related to HBV and HCV infection in HCC patients. Serum anti-Ku86 antibody may be a potential biomarker for early detection of HCC, and can be used in combination with AFP in clinics.

Differential mRNA expression profiles between hepatocellular carcinoma and adjacent normal liver tissue

Differential mRNA expression profiles between hepatocellular carcinoma and adjacent normal liver tissue

Identification of intragenic methylation in the TUSC1 gene as a novel prognostic marker of hepatocellular carcinoma

Patients with hepatocellular carcinoma (HCC) have a poor prognosis, and novel molecular targets for treating recurrence and progression of the disease along with associated biomarkers are urgently required. In the present study, expression and the regulatory mechanism of TUSC1 (tumor suppressor candidate 1) were investigated to determine if it is a candidate tumor suppressor gene for HCC, which shows repressed transcription that involves aberrant DNA methylation. TUSC1 mRNA expression levels in HCC cell lines and 94 pairs of surgical specimens were determined using quantitative real-time reverse transcription polymerase chain reaction assay. Methylation status of HCC cell lines and clinical samples were analyzed to investigate the regulatory mechanism of TUSC1 transcription and the relationship between the methylation status of the TUSC1 gene and clinicopathological factors. The expression and distribution of the TUSC1 protein in liver tissues were determined using immunohistochemistry. A majority of HCC cell lines (89%) and surgical specimens (84%) demonstrated reduced expression levels of TUSC1 mRNA compared with paired non-cancerous liver tissues. The mean mRNA expression level in HCC was significantly lower than in corresponding non-cancerous liver. In contrast, no significant difference was found in TUSC1 mRNA expression level between adjacent normal and cirrhotic liver tissue from HCC patients. The TUSC1 protein expression pattern in HCC and liver tissues was consistent with TUSC1 mRNA expression. Twenty-nine (31%) of 94 patients showed intragenic hypermethylation of the TUSC1 gene in HCC, and hypermethylation was significantly associated with advanced pathological stage. Subsequently, patients with hypermethylation of the TUSC1 gene had a significantly poorer prognosis than patients without hypermethylation. Our results suggest that TUSC1 is a candidate tumor suppressor gene and intragenic hypermethylation is one of the suppressive mechanisms that regulate TUSC1 transcription in HCC. Intragenic methylation of the TUSC1 gene may serve as a novel prognostic marker of HCC.

Comprehensive analyses of imprinted differentially methylated regions reveal epigenetic and genetic characteristics in hepatoblastoma

BackgroundAberrant methylation at imprinted differentially methylated regions (DMRs) in human 11p15.5 has been reported in many tumors including hepatoblastoma. However, the methylation status of imprinted DMRs in imprinted loci scattered through the human genome has not been analyzed yet in any tumors.MethodsThe methylation statuses of 33 imprinted DMRs were analyzed in 12 hepatoblastomas and adjacent normal liver tissue by MALDI-TOF MS and pyrosequencing. Uniparental disomy (UPD) and copy number abnormalities were investigated with DNA polymorphisms.ResultsAmong 33 DMRs analyzed, 18 showed aberrant methylation in at least 1 tumor. There was large deviation in the incidence of aberrant methylation among the DMRs. KvDMR1 and IGF2-DMR0 were the most frequently hypomethylated DMRs. INPP5Fv2-DMR and RB1-DMR were hypermethylated with high frequencies. Hypomethylation was observed at certain DMRs not only in tumors but also in a small number of adjacent histologically normal liver tissue, whereas hypermethylation was observed only in tumor samples. The methylation levels of long interspersed nuclear element-1 (LINE-1) did not show large differences between tumor tissue and normal liver controls. Chromosomal abnormalities were also found in some tumors. 11p15.5 and 20q13.3 loci showed the frequent occurrence of both genetic and epigenetic alterations.ConclusionsOur analyses revealed tumor-specific aberrant hypermethylation at some imprinted DMRs in 12 hepatoblastomas with additional suggestion for the possibility of hypomethylation prior to tumor development. Some loci showed both genetic and epigenetic alterations with high frequencies. These findings will aid in understanding the development of hepatoblastoma.