Hepatocyte nuclear factor 4α (HNF4α) is a transcription factor that plays a key role in hepatocyte differentiation and the maintenance of hepatic function, but its role in hepatocarcinogenesis has yet to be examined. Here, we report evidence of a suppressor role for HNF4α in liver cancer. HNF4α expression was progressively decreased in the diethylinitrosamine-induced rat model of liver carcinogenesis. In human liver tissues, HNF4α expression was decreased in cirrhotic tissue and further decreased in hepatocarcinoma relative to healthy tissue. Notably, an inverse correlation existed with epithelial-mesenchymal transition (EMT). Enforced expression of HNF4α attenuated hepatocyte EMT during hepatocarcinogenesis, alleviated hepatic fibrosis, and blocked hepatocellular carcinoma (HCC) occurrence. In parallel, stem cell marker gene expression was inhibited along with cancer stem/progenitor cell generation. Further, enforced expression of HNF4α inhibited activation of β-catenin, which is closely associated with EMT and hepatocarcinogenesis. Taken together, our results suggest that the inhibitory effect of HNF4α on HCC development might be attributed to suppression of hepatocyte EMT and cancer stem cell generation through an inhibition of β-catenin signaling pathways. More generally, our findings broaden knowledge on the biological significance of HNF4α in HCC development, and they imply novel strategies for HCC prevention through the manipulation of differentiation-determining transcription factors in various types of carcinomas.

Previous studies have shown that hepatocyte nuclear factor-4␣ (HNF4␣) is a central regulator of differentiated hepatocyte phenotype and forced expression of HNF4␣ could promote reversion of tumors toward a less invasive phenotype. However, the effect of HNF4␣ on cancer stem cells (CSCs) and the treatment of hepatocellular carcinoma (HCC) with HNF4␣ have not been reported. In this study, an adenovirus-mediated gene delivery system, which could efficiently transfer and express HNF4␣, was generated to determine its effect on hepatoma cells (Hep3B and H epatocellular carcinoma (HCC) is one of the most common cancers worldwide, and in the United States its incidence has increased by more than 90% in the past three decades. 1 Despite great advances in detection and treatment of the disease, the mortality rate remains high-especially in the advanced stage, when the disease is usually diagnosed. Even if anticancer therapies could shrink primary and metastatic tumors, such effects are usually transient, and most metastatic cancers relapse frequently.Recent evidence has demonstrated that tumors are organized in a hierarchy of heterogeneous cell populations with different biologic properties and that the populations consist of cancer stem cells (CSCs), proliferating Abbreviations: CSC, cancer stem cell; GFP, green fluorescent protein; HCC, hepatocellular carcinoma; HNF4␣, mRNA, messenger RNA; PBS, PCR, polymerase chain reaction; From the

The use of a stent as a bridge to surgery for obstructive left-sided colorectal cancer could increase the chance of primary anastomosis and reduce the need for stoma creation and postprocedural complications. Stent insertion before subsequent surgery has no effect on perioperative mortality and long-term survival.

Hepatocyte nuclear factor-1alpha (HNF1a) is one of the key transcription factors of the HNF family, which plays a critical role in hepatocyte differentiation. Substantial evidence has suggested that down-regulation of HNF1a may contribute to the development of hepatocellular carcinoma (HCC). Herein, human cancer cells and tumor-associated fibroblasts (TAFs) were isolated from human HCC tissues, respectively. A recombinant adenovirus carrying the HNF1a gene (AdHNF1a) was constructed to determine its effect on HCC in vitro and in vivo. Our results demonstrated that HCC cells and HCC tissues revealed reduced expression of HNF1a. Forced reexpression of HNF1a significantly suppressed the proliferation of HCC cells and TAFs and inhibited the clonogenic growth of hepatoma cells in vitro. In parallel, HNF1a overexpression reestablished the expression of certain liver-specific genes and microRNA 192 and 194 levels, with a resultant increase in p21 levels and induction of G 2 /M arrest. Additionally, AdHNF1a inhibited the expression of cluster of differentiation 133 and epithelial cell adhesion molecule and the signal pathways of the mammalian target of rapamycin and transforming growth factor beta/Smads. Furthermore, HNF1a abolished the tumorigenicity of hepatoma cells in vivo. Most interestingly, intratumoral injection of AdHNF1a significantly inhibited the growth of subcutaneous HCC xenografts in nude mice. Systemic delivery of AdHNF1a could eradicate the orthotopic liver HCC nodules in nonobese diabetic/severe combined immunodeficiency mice. Conclusion: These results suggest that the potent inhibitive effect of HNF1a on HCC is attained by inducing the differentiation of hepatoma cells into mature hepatocytes and G 2 /M arrest. HNF1a might represent a novel, promising therapeutic agent for human HCC treatment. Our findings also encourage the evaluation of differentiation therapy for tumors of organs other than liver using their corresponding differentiation-determining transcription factor.

Long-term treatment with mid-dose UDCA can improve liver biochemistry and survival free of liver transplantation in patients with PBC. In addition, UDCA therapy can delay the histological progression in the early-stage patients.

Hepatocytes are critical for the maintenance of liver homeostasis, but its involvement in hepatic fibrogenesis remains elusive. Hepatocyte nuclear factor 1α (HNF1α) is a liver-enriched transcription factor that plays a key role in hepatocyte function. Our previous study revealed a significant inhibitory effect of HNF1α on hepatocellular carcinoma. In this study, we report that the expression of HNF1α is significantly repressed in both human and rat fibrotic liver. Knockdown of HNF1α in the liver significantly aggravates hepatic fibrogenesis in either dimethylnitrosamine (DMN) or bile duct ligation (BDL) model in rats. In contrast, forced expression of HNF1α markedly alleviates hepatic fibrosis. HNF1α regulates the transcriptional expression of SH2 domain-containing phosphatase-1 (SHP-1) via directly binding to SHP-1 promoter in hepatocytes. Inhibition of SHP-1 expression abrogates the anti-fibrotic effect of HNF1α in DMN-treated rats. Moreover, HNF1α repression in primary hepatocytes leads to the activation of NF-κB and JAK/STAT pathways and initiates an inflammatory feedback circuit consisting of HNF1α, SHP-1, STAT3, p65, miR-21 and miR-146a, which sustains the deregulation of HNF1α in hepatocytes. More interestingly, a coordinated crosstalk between hepatocytes and hepatic stellate cells (HSCs) participates in this positive feedback circuit and facilitates the progression of hepatocellular damage. Our findings demonstrate that impaired hepatocytes play an active role in hepatic fibrogenesis. Early intervention of HNF1α-regulated inflammatory feedback loop in hepatocytes may have beneficial effects in the treatment of chronic liver diseases.

MicroRNA 370 (miR-370) is located within the DLK1/DIO3 imprinting region on human chromosome 14, which has been identified as a cancer-associated genomic region. However, the role of miR-370 in malignances remains controversial. Here, we report that miR-370 was repressed in human hepatocellular carcinoma (HCC) tissues and hepatoma cell lines. Using gain-of-function and loss-of-function experiments, we demonstrated that miR-370 inhibited the malignant phenotype of HCC cells in vitro. Overexpression of miR-370 inhibited growth and metastasis of HCC cells in vivo. Moreover, the RNA-binding protein, LIN28A, was identified as a direct functional target of miR-370, which, in turn, blocked the biogenesis of miR-370 by binding to its precursor. LIN28A also mediated the suppressive effects of miR-370 on migration and invasion of HCC cells by post-transcriptionally regulating RelA/p65, which is an important effector of the canonical nuclear factor kappa B (NF-jB) pathway. Interleukin-6 (IL-6), a wellknown NF-jB downstream inflammatory molecule, reduced miR-370 but increased LIN28A levels in HCC. Furthermore, miR-370 levels were inversely correlated with LIN28A and IL-6 messenger RNA (mRNA) levels, whereas LIN28A mRNA expression was positively correlated with IL-6 expression in human HCC samples. Interestingly, reduction of miR-370 expression was associated with the development of HCC in rats, as well as with aggressive tumor behavior and short survival in HCC patients. Conclusions: These data demonstrate the involvement of a novel regulatory circuit consisting of miR-370, LIN28A, RelA/p65 and IL-6 in HCC progression. Manipulating this feedback loop may have beneficial effect in HCC treatment. (HEPATOLOGY 2013;58:1977-1991 H epatocellular carcinoma (HCC) is one of the most common cancers worldwide, especially in Asia. 1 Most HCCs develop on a background of chronic inflammation caused by hepatitis virus, toxins, metabolic impairment, or autoimmune hepatopathy. 2 Inflammatory molecules can provide signals that promote the proliferation and metastasis of

Extracellular signal-regulated kinase 1 (ERK1) is a critical part of the mitogen-activated protein kinase signal transduction pathway, which is involved in hepatic fibrosis. However, the effect of down-regulation of ERK1 on hepatic fibrosis has not been reported. Here, we induced hepatic fibrosis in rats with dimethylnitrosamine administration or bile duct ligation. An adenovirus carrying small interfering RNA targeting ERK1 (AdshERK1) was constructed to determine its effect on hepatic fibrosis, as evaluated by histological and immunohistochemical examination. Our results demonstrated that AdshERK1 significantly reduced the expression of ERK1 and suppressed proliferation and levels of fibrosis-related genes in hepatic stellate cells in vitro. More importantly, selective inhibition of ERK1 remarkably attenuated the deposition of the extracellular matrix in fibrotic liver in both fibrosis models. In addition, both hepatocytes and biliary epithelial cells were proven to exert the ability to generate the myofibroblasts depending on the insults of the liver, which were remarkably reduced by AdshERK1. Furthermore, up-regulation of ERK1 paralleled the increased expression of transforming growth factor ␤1 (TGF-␤1), vimentin, snail, platelet-derived growth factor-BB (PDGF-BB), bone morphogenetic protein 4 (BMP4), and small mothers against decapentaplegic-1 (p-Smad1), and was in reverse correlation with E-cadherin in the fibrotic liver. Nevertheless, inhibition of ERK1 resulted in the increased level of E-cadherin in parallel with suppression of TGF-␤1, vimentin, snail, PDGF-BB, BMP4, and p-Smad1. Interestingly, AdshERK1 treatment promoted hepatocellular proliferation. Conclusion: Our study provides the first evidence for AdshERK1 suppression of hepatic fibrosis through the reversal of epithelial-mesenchymal transition of both hepatocytes and biliary epithelial cells without interference of hepatocellular proliferation. This suggests that ERK1 is implicated in hepatic fibrogenesis and selective inhibition of ERK1 by small interfering RNA may present a novel option for hepatic fibrosis treatment. (HEPATOLOGY 2009;50:1524-1536 H epatic fibrosis is the response of the liver to different chronic insults, and is characterized by the excess production and deposition of extracellular matrix (ECM) components, leading to tissue scarring and the destruction of normal hepatic parenchyma. 1 A very large number of studies have identified the hepatic stellate cells (HSCs) as the predominant source of myofibroblasts. [2][3][4] Nevertheless, recent studies suggest that