Qiujin Shen

High expression of Dickkopf-related protein 1 is related to lymphatic metastasis and indicates poor prognosis in intrahepatic cholangiocarcinoma patients after surgery

Dickkopf‐related protein 1 (DKK1) has been reported involved in metastasis and invasion in several tumors. This study sought to investigate the prognostic value of DKK1 in intrahepatic cholangiocarcinoma (ICC) and its role in promoting ICC metastasis.

Epigenetic silencing of WIF-1 in hepatocellular carcinomas

PurposeTo examine the expression profile and promoter methylation status of WIF-1 in hepatocellular carcinoma (HCC) and identify the possible relationship between the WIF-1 expression pattern and promoter methylation status.MethodsQuantitative real-time PCR was performed to detect mRNA level of WIF-1 in 4 HCC cell lines, 15 paired HCC clinical samples and 3 normal liver tissues. Methylation-specific PCR and bisulfite DNA sequencing were used in methylation analysis. In vitro assays for HCC cells, colony formation and cell proliferation assay were carried out to observe the effect of WIF-1 on cell growth; TOP-flash luciferase analysis was employed to determine its role in the Wnt pathway.ResultsQuantitative real-time PCR analysis showed the extensive low expression of WIF-1 mRNA in HCC, and this down-regulation was generally dependent on the degree of methylation at its promoter region. In vitro assays indicated WIF-1 can inhibit cell growth by blocking Wnt signaling in HCC cells.ConclusionsWIF-1 silencing as a result of its promoter hypermethylation may be a frequent event in HCC.

Overexpression of Dickkopf-1 predicts poor prognosis for patients with hepatocellular carcinoma after orthotopic liver transplantation by promoting cancer metastasis and recurrence

AbstractOur previous data had shown that Dickkopf-1 (DKK1) combined with β-catenin was a novel prognostic predictor for hepatocellular carcinoma (HCC) patients. However, the role and mechanism of DKK1 in HCC recurrence or metastasis remain poorly understand. This study was to assess the role of DKK1 in tumor metastasis for patients with hepatocellular carcinoma after orthotopic liver transplantation (OLT). The expression of DKK1 protein was detected in hepatic cell lines, HCC cell lines, and HCC patients after OLT with different potential of metastasis. After DKK1 expression in the HCCLM3 cells was downregulated by siRNA-mediated approach, the role of DKK1 in cell invasion and metastasis was investigated. cDNA genechip was used to analyze the differential expressed genes related with DKK1 in two pairs of HCC cells. The prognostic significance of DKK1 was further assessed by Kaplan–Meier and Cox regression analyses in 148 HCC patients after OLT. The expression of DKK1 protein was higher in the high-invasive HCC cells and HCC patients of the disease recurrence group. With the downregulation of DKK1, HCCLM3 cells showed decreased aggressiveness in vitro and lower metastatic ability in vivo. DKK1 could regulate many genes involved in biological processes and pathways related with tumor progression. Furthermore, DKK1 overexpression correlated with tumor microvessel density in clinical HCC samples. Multivariate analysis revealed that DKK1 was an independent prognostic indicator for overall survival and cumulative recurrence in this cohort of HCC patients post-OLT. Collectively, overexpression of DKK1 was implicated in invasion/metastasis of HCC after OLT and DKK1 overexpression may be potential molecular therapeutic targets for liver cancer.

Hepatitis B virus X protein co-activates pregnane X receptor to induce the cytochrome P450 3A4 enzyme, a potential implication in hepatocarcinogenesis

BACKGROUND Hepatitis B virus X protein is a key regulator of hepatocarcinogenesis. The pregnane X receptor is a xenobiotic nuclear receptor that plays a role in the regulation of drug-metabolizing enzymes including the cytochrome P450 3A4, an enzyme important for the bioactivation of the liver carcinogen aflatoxin B1. AIMS To identify novel host factor that interacts with hepatitis B virus X protein and the functional interaction between hepatitis B virus X protein and pregnane X receptor in hepatocarcinogenesis. METHODS Co-immunoprecipitation, glutathione S-transferase pull-down, and chromatin immunoprecipitation were utilized to assess the interaction between hepatitis B virus X protein and pregnane X receptor. The functional relevance of hepatitis B virus X protein-pregnane X receptor interaction was investigated in cell cultures and hepatocellular carcinoma samples. RESULTS We observed that hepatitis B virus X protein and pregnane X receptor co-localize in hepatic cells. Pregnane X receptor interacted with hepatitis B virus X protein via the ligand-binding domain of pregnane X receptor. Functionally, hepatitis B virus X protein increased the transcriptional activity of pregnane X receptor. Pregnane X receptor was able to recruit hepatitis B virus X protein to the CYP3A4 gene promoter. In clinic samples, the expression of pregnane X receptor was high in hepatitis B virus-associated liver cirrhosis and stage I hepatocellular carcinoma, but low in state II and stage III hepatocellular carcinoma. CONCLUSION We revealed a novel function of hepatitis B virus X protein in co-activating pregnane X receptor. The increased expression of pregnane X receptor and its target gene CYP3A4 are potential biomarkers for the early stage of hepatitis B virus-associated hepatocarcinogenesis.

Neuropeptide Y1 receptor inhibits cell growth through inactivating mitogen-activated protein kinase signal pathway in human hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers, and its incidence is increasing worldwide. Neuropeptide Y (NPY) broadly expressed in the central and peripheral nervous system. It participates in multiple physiological and pathological processes through specific receptors. Evidences are accumulating that NPY is involved in development and progression in neuro- or endocrine-related cancers. However, little is known about the potential roles and underlying mechanisms of NPY receptors in HCC. In this study, we analyzed the expression of NPY receptors by real-time polymerase chain reaction, Western blot, and immunohistochemical staining. Correlation between NPY1R levels and clinicopathological characteristics, and survival of HCC patients were explored, respectively. Cell proliferation was researched by CCK-8 in vitro, and tumor growth was studied by nude mice xenografts in vivo. We found that mRNA and protein level of NPY receptor Y1 subtype (NPY1R) significantly decreased in HCC tissues. Low expression of NPY1R closely correlated with poor prognosis in HCC patients. Proliferation of HCC cells was significantly inhibited by recombinant NPY protein in vitro. This inhibitory effect could be blocked by selected NPY1R antagonist BIBP3226. Furthermore, overexpression of NPY1R could significantly inhibit HCC cell proliferation. Knockdown of NPY1R promoted cell multiplication in vitro and increased tumorigenicity and tumor growth in vivo. NPY1R was found to participate in the inhibition of cell proliferation via inactivating mitogen-activated protein kinase signal pathway in HCC cells. Collectively, NPY1R plays an inhibitory role in tumor growth and may be a promising therapeutic target for HCC.

High level of serum protein DKK1 predicts poor prognosis for patients with hepatocellular carcinoma after hepatectomy

Aim To evaluate prognostic significance of DKK1 for hepatocelluar carcinoma. Materials & methods We enrolled a test cohort consisting of 266 hepatitis virus B-related hepatocelluar carcinoma patients who had undergone hepatectomy and a validation cohort of 95. Associations of DKK1 with overall survival and time to recurrence were determined by Cox proportional hazards regression model. Results High levels of preoperative serum DKK1 were associated with poor overall survival and higher recurrence rate and DKK1 was an independent prognostic predictor. Moreover, DKK1 maintained ability to predict recurrence for patients with low recurrence risk. Double positives of DKK1 and AFP indicated the worst overall survival and the highest recurrence rate compared with either used alone. Patients with preoperatively and 1-day postoperatively positive DKK1 had higher recurrence rates than those whose values were both negative. Similar results were found in the validation cohort. Conclusion Serum DKK1 could predict prognosis of hepatocelluar carcinoma after hepatectomy.