Yes-associated protein expression is a predictive marker for recurrence of hepatocellular carcinoma after liver transplantation

Molecular Clues for Prediction of Hepatocellular Carcinoma Recurrence After Liver Transplantation

Recurrence after liver transplantation (LT) for hepatocellular carcinoma (HCC) is one of the commonest causes of cancer-related mortality. Thus, advances in the HCC molecular features have paid researchers great attention to identifying the different risk factors that could aid in liver cancer initiation and progression for earlier prediction of post-operative HCC recurrence risk. Our review has focused on the possible molecular onco-drivers' for HCC recurrence post-LT that may represent diagnostic/prognostic tools and scoring models for the proper selection of LT candidates with HCC.

Relationship between Yes-Associated Protein 1 and Prognosis of Digestive System Neoplasm: Quantitative Analysis and Bioinformatics Analysis Based on 4023 Patients

Yes-associated protein 1 (YAP1) is involved in the development of a variety of malignancies. However, the prognosis of malignant digestive tumors with YAP1 expression is still controversial. This study searched 31 articles with 36 data sets of 4023 patients to explore the role of YAP1 expression on the prognosis of digestive malignant tumors by searching the PubMed, Embase, Web of Science, Google Scholar, and Cochrane Library databases. Specifically, relevant cancer expression matrix data were downloaded from The Cancer Genome Atlas (TCGA) database. In this meta-analysis, quantitative analysis showed that the overexpression of YAP1 was not conducive to OS (1.62, 95% CI (1.38, 1.90), P=0.001) and DFS (1.59, 95% CI (1.31, 1.93), P=0.001) in patients with digestive malignant tumors. In addition, TCGA database analysis showed that YAP1 was overexpressed in gastric cancer, cholangiocarcinoma, and colorectal cancer. Survival analysis showed that the patients with high expression of YAP1 in pancreatic cancer have a poor OS (MST: 394 vs. 691 days, P < 0.0001) and DFS (MST: 371 vs. 542 days, P=0.026) prognosis. YAP1 may be a molecular marker that effectively predicts the survival of malignant digestive tumors, especially pancreatic cancer, and is a potential therapeutic target for malignant digestive tumors.

The RNA binding protein QKI5 suppresses ovarian cancer via downregulating transcriptional coactivator TAZ

RNA-binding proteins (RBPs) are a set of proteins involved in many steps of post-transcriptional regulation to maintain cellular homeostasis. Ovarian cancer (OC) is the most deadly gynecological cancer, but the roles of RBPs in OC are not fully understood. Here, we reported that the RBP QKI5 was significantly negatively correlated with aggressive tumor stage and worse prognosis in serous OC patients. QKI5 could suppress the growth and metastasis of OC cells both in vitro and in vivo. Transcriptome analysis showed that QKI5 negatively regulated the expression of the transcriptional coactivator TAZ and its downstream targets (e.g., CTGF and CYR61). Mechanistically, QKI5 bound to TAZ mRNA and recruited EDC4, thus decreasing the stability of TAZ mRNA. Functionally, TAZ was involved in the QKI5-mediated tumor suppression of OC cells, and QKI5 expression was inversely correlated with TAZ, CTGF, and CYR61 expression in OC patients. Together, our study indicates that QKI5 plays a tumor-suppressive role and negatively regulates TAZ expression in OC.

Yes-associated protein expression is associated with poor prognosis in patients with colorectal cancer

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide. The aim of the present study was to investigate the expression of yes-associated protein (YAP) in CRC tissues, and to determine the relationship between the expression levels of YAP and the clinicopathological characteristics and prognosis of patients with CRC. Bioinformatics analysis was conducted to examine the expression of YAP and its correlation with clinicopathological characteristics and key genes, using functional enrichment analysis. Immunohistochemistry was used to detect YAP expression in 181 CRC tissue samples and 30 normal colorectal mucosa samples. Western blotting and reverse transcription-quantitative PCR were performed to detect the expression of YAP and β-catenin in CRC cells, and cellular proliferation was assessed using a Cell Counting Kit-8 assay. Finally, apoptosis was analyzed using flow cytometry. Immunohistochemical staining indicated that the positive expression rate of YAP in CRC tissues was 73.5%, which was significantly higher than that in normal colorectal mucosa samples. The expression of YAP in CRC was associated with histological differentiation, lymph node metastasis and Duke's stage. However, no significant associations were observed between YAP expression and age, sex and T stage. Downregulation of YAP promoted the proliferation and the inhibited apoptosis of CRC cells, and YAP expression was positively correlated with that of β-catenin in both CRC tissues and cells. Furthermore, YAP expression was upregulated in CRC tissues, which was correlated with tumor progression and prognosis. Therefore, YAP expression may be used as an independent predictor of poor prognosis in patients with CRC, and the underling molecular mechanism may be associated with the combined effect of Hippo and Wnt/β-catenin signaling.

MicroRNAs Regulating Hippo-YAP Signaling in Liver Cancer

Liver cancer is one of the most common cancers worldwide, and its prevalence and mortality rate are increasing due to the lack of biomarkers and effective treatments. The Hippo signaling pathway has long been known to control liver size, and genetic depletion of Hippo kinases leads to liver cancer in mice through activation of the downstream effectors yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). Both YAP and TAZ not only reprogram tumor cells but also alter the tumor microenvironment to exert carcinogenic effects. Therefore, understanding the mechanisms of YAP/TAZ-mediated liver tumorigenesis will help overcome liver cancer. For decades, small noncoding RNAs, microRNAs (miRNAs), have been reported to play critical roles in the pathogenesis of many cancers, including liver cancer. However, the interactions between miRNAs and Hippo-YAP/TAZ signaling in the liver are still largely unknown. Here, we review miRNAs that influence the proliferation, migration and apoptosis of tumor cells by modulating Hippo-YAP/TAZ signaling during hepatic tumorigenesis. Previous findings suggest that these miRNAs are potential biomarkers and therapeutic targets for the diagnosis, prognosis, and treatment of liver cancer.

Expression of YAP in endometrial carcinoma tissues and its effect on epithelial to mesenchymal transition

Background

Yes-associated protein (YAP) can function as a cancer suppressor or a cancer promoter. Studies have proved that YAP can collaborate with other genes to accelerate cancerous epithelial to mesenchymal transition (EMT), but little is known about how YAP performs in endometrial carcinoma (EC).

Methods

Real time-polymerase chain reaction (RT-PCR) and western blot (WB) were used to quantify the relative mRNA and protein levels of YAP in 50 EC tissue samples and 20 normal endometrial tissues in the proliferative phase. The association between YAP expression level and EC index (clinical stage, histologic grade, and lymphatic metastasis) was analyzed. YAP interference and overexpression vectors were constructed. RT-PCR and WB were used to quantify the mRNA and protein levels of YAP and EMT markers in the normal control group (N), the negative control group (NC), and the YAP interference and overexpression group. Cell counting kit-8 (CCK8) assay and scratch test were performed to evaluate the proliferation, invasion, and migration of EC cells after YAP interference and overexpression.

Results

The mRNA and protein levels of YAP increased in EC tissues (P<0.01) and showed differences associated with histologic grade and lymphatic metastasis, not with the clinical stage (P>0.01). CCK8 assay showed that the proliferation of EC cells was inhibited after YAP interference and increased after YAP overexpression. The cell wound healing test displayed that the migration of EC cells was inhibited after YAP interference and increased after YAP overexpression. RT-PCR and WB found the mRNA and protein levels of E-cadherin (an EMT marker) increased (P<0.01), but those of other markers (N-cadherin, Vimentin) dropped (P<0.01) after YAP interference; however, these trends were inversed after YAP overexpression (P<0.01).

Conclusions

YAP serves as an EC-promoting gene that may regulate the EMT and other EC-related processes via promoting the proliferation, invasion, and migration of EC cells.

Progress in research on association between cell signal transduction pathways and hepatocellular carcinoma

Cell signal transduction refers to the process by which a signal molecule induces signal transduction in a cell by stimulating the cell membrane or intracellular receptor, thereby affecting the biological function of the cell. In recent years, studies have found that the activation or inhibition of certain cell signal transduction pathways plays an important role in the development and progression of hepatocellular carcinoma. This article will review the recent research progress in the understanding of the role of some common signal transduction pathways in hepatocellular carcinoma.

The prognostic value of YAP1 on clinical outcomes in human cancers

BACKGROUND

As an important downstream factor in the Hippo pathway, yes-associated protein 1(YAP1) has been detected to be elevated in various cancers and demonstrated to play a role in tumor development. Therefore, we evaluated by a meta-analysis the prognostic value of YAP1 in cancer patients.

RESULTS

Sixty-eight studies with 8631 patients were identified. The results indicated that YAP1 overexpression predicted unfavorable patient prognosis in studies with overall survival (OS) (HR=1.76, 95%CI: 1.50-2.06, p<0.001) and disease-free survival (DFS) (HR=1.39, 95%CI: 1.22-1.59, p<0.001), as well as in studies with recurrence-free survival (RFS) (HR=2.38, 95%CI: 1.73-3.27, p<0.001), and disease-specific survival (DSS) (HR=2.04, 95%CI: 1.55-2.70, p<0.001). Meanwhile, YAP1 overexpression was also observed to be significantly associated with worse OS in GEPIA (HR=1.2, p<0.001).

CONCLUSIONS

Overexpression of YAP1 showed great association with poorer prognosis in patients with various cancers, particularly liver cancer. Therefore, YAP1 might be an important prognostic marker and a novel target of cancer therapy.

METHODS

We searched for potential publications in several online databases and retrieved relevant data. Overall and subgroup analyses were performed. Begg's and Egger's tests were used to assess publication bias. Online dataset GEPIA was used to generate the survival curves and verify the prognostic role of YAP1 in patients with tumors.

Activating Hippo Pathway via Rassf1 by Ursolic Acid Suppresses the Tumorigenesis of Gastric Cancer

The Hippo pathway is often dysregulated in many carcinomas, which results in various stages of tumor progression. Ursolic acid (UA), a natural compound that exists in many herbal plants, is known to obstruct cancer progression and exerts anti-carcinogenic effect on a number of human cancers. In this study, we aimed to examine the biological mechanisms of action of UA through the Hippo pathway in gastric cancer cells. MTT assay showed a decreased viability of gastric cancer cells after treatment with UA. Following treatment with UA, colony numbers and the sizes of gastric cancer cells were significantly diminished and apoptosis was observed in SNU484 and SNU638 cells. The invasion and migration rates of gastric cancer cells were suppressed by UA in a dose-dependent manner. To further determine the gene expression patterns that are related to the effects of UA, a microarray analysis was performed. Gene ontology analysis revealed that several genes, such as the Hippo pathway upstream target gene, ras association domain family (RASSF1), and its downstream target genes (MST1, MST2, and LATS1) were significantly upregulated by UA, while the expression of YAP1 gene, together with oncogenes (FOXM1, KRAS, and BATF), were significantly decreased. Similar to the gene expression profiling results, the protein levels of RASSF1, MST1, MST2, LATS1, and p-YAP were increased, whereas those of CTGF were decreased by UA in gastric cancer cells. The p-YAP expression induced in gastric cancer cells by UA was reversed with RASSF1 silencing. In addition, the protein levels in the Hippo pathway were increased in the UA-treated xenograft tumor tissues as compared with that in the control tumor tissues; thus, UA significantly inhibited the tumorigenesis of gastric cancer in vivo in xenograft animals. Collectively, UA diminishes the proliferation and metastasis of gastric cancer via the regulation of Hippo pathway through Rassf1, which suggests that UA can be used as a potential chemopreventive and therapeutic agent for gastric cancer.

Correlation between CT features and liver function and p53 expression in hepatitis, cirrhosis and hepatocellular carcinoma

This study aimed to investigate the correlation between CT features and liver function and p53 expression in hepatitis, cirrhosis and hepatocellular carcinoma (HCC). Forty patients with HCC, 30 patients with cirrhosis and 30 patients with chronic hepatitis were enrolled between December, 2015 and December, 2016. At the same time, normal liver tissues collected from 30 patients with hepatic hemangioma were used as the normal control group. All the patients were scanned by CT. Average body surface area, left outer lobe and caudate lobe volume, and the proportions of left outer lobe and caudate lobe to the whole liver were calculated. Biochemical indexes of liver function were determined. The pathological tissues of all the subjects were analyzed. Compared with the control group, total liver volume of the HCC group was significantly reduced (P<0.05). Compared with the HCC group, the volume of the left outer lobe increased in the hepatitis group and the cirrhosis group. Compared with control group, caudate lobe volume increased significantly in the hepatitis group (P<0.05). Compared with the control group, the volume of the left outer lobe and the proportion of caudate lobe to the whole liver volume was significantly increased in all three groups (P<0.05). Liver function-related indicators in the HCC and cirrhosis groups were significantly different from those in the control group (P<0.05). The expression level of p53 in HCC was significantly higher than that in the control group (P<0.05). The accuracy of diagnosis by using both p53 and CT was higher than the use of p53 or CT alone. CT can accurately measure the volume of each lobe of the liver, and p53 has important clinical values in the diagnosis of liver diseases. Thus, the reasonable combination of the two can effectively improve the diagnostic accuracy.

PTEN lipid phosphatase inactivation links the hippo and PI3K/Akt pathways to induce gastric tumorigenesis

Background

Phosphatase and tensin homolog (PTEN) is an important tumor suppressor gene, and its encoded protein has activities of both a protein phosphatase and a lipid phosphatase. However, the substitution effect of protein phosphatase activity remains unclear. PI3K/Akt is the most common pathway negatively regulated by PTEN. The Hippo and PI3K/Akt pathways have a joint effect in regulating cell proliferation and apoptosis. Therefore, how PTEN lipid phosphatase inactivation contributes to the occurrence and development of gastric cancer and the potential role of the Hippo and PI3K/Akt pathways in PTEN lipid phosphatase inactivation mediated gastric tumorigenesis remain to be explored.

Methods

Immunohistochemical staining was performed to detect the expression of p-PTEN and YAP in a gastric cancer tissue microarray. Stable cell lines expressing a wild-type or dominant-negative mutant PTEN were established. The proliferation and migration of stable cells were detected by MTT, BrdU, and colony-formation, transwell assay and high content analysis in vitro, and tumor growth differences were observed in xenograft nude mice. Changes in the expression of key molecules in the Hippo and Akt signaling pathways were detected by western blot. Nuclear-cytoplasm separation, immunofluorescence and coimmunoprecipitation analyses were conducted to explore the dysregulation of Hippo in the stable cell lines.

Results

PTEN lipid phosphatase inactivation strongly promoted the proliferation and migration of gastric cancer cells in vitro and tumor growth in vivo. A immunohistochemical analysis of gastric cancer tissues revealed a significant correlation between phosphorylated PTEN and nuclear YAP expression, and both were determined to be independent prognostic factors for gastric cancer. Mechanistically, PTEN lipid phosphatase inactivation abolished the MOB1-LATS1/2 interaction, decreased YAP phosphorylation and finally promoted YAP nuclear translocation, which enhanced the synergistic effect of YAP-TEAD, thus inducing cell proliferation and migration. Moreover, PTEN lipid phosphatase inactivation promoted the PI3K/Akt pathway, and disruption of YAP-TEAD-driven transcription decreased the activation of Akt in a dose-dependent manner.

Conclusions

Taken together, our findings indicate that PTEN lipid phosphatase inactivation links the Hippo and PI3K/Akt pathways to promote gastric tumorigenesis and cancer development.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0795-2) contains supplementary material, which is available to authorized users.

Downregulation of YAP inhibits proliferation, invasion and increases cisplatin sensitivity in human hepatocellular carcinoma cells

Yes-associated protein (YAP) serves an essential role in tumorigenesis. However, the potential role and the molecular mechanism underlying the effect of YAP on hepatocellular carcinoma (HCC) cells have not been elucidated. In the current study, it was revealed that YAP expression was increased significantly in HCC cancer tissues and its overexpression was associated with tumor differentiation. The silencing of YAP by small interferring RNA led to the inhibition of HCC cell growth, which was associated with the promotion of apoptosis. The silencing of YAP also decreased the invasive potential of HCC cells and the activity of the phosphoinositide 3-kinase (PI3K)/AKT serine/threonine kinase (AKT) signaling pathway. Furthermore, silencing of YAP increased the chemosensitivity of HCC cells to cisplatin (CDDP) through inactivation of the PI3K/AKT signaling pathway. In vivo studies using PDTX model suggested a promotive role for YAP in the growth of HCC and knockdown of YAP increased the anti-tumor activity of CDDP. Taken together, these results revealed that YAP is overexpressed in HCC, and promotes proliferation, invasion and drug resistance of HCC cells. Inhibition of YAP, alone or in combination with traditional chemotherapy, may effectively combat HCC.

Standard CD44 modulates YAP1 through a positive feedback loop in hepatocellular carcinoma

High expression levels of CD44 and YAP have been identified as poor prognostic factors in hepatocellular carcinoma (HCC). However, the mechanistic relationship between CD44 and YAP during HCC tumorigenesis remains largely unknown. To investigate the mutual regulation between standard CD44 (CD44S) and YAP1 in HCC cell lines and tissue samples, CD44S and YAP1 expression in 40 pairs of tumor samples and matched distal normal tissues from HCC patients was examined by immunohistochemical staining. High expression of either CD44S or YAP1 was associated with a younger age and worse pathology grade. In addition, high levels of CD44S and YAP1 were associated with increased vascular invasion and more severe liver cirrhosis, respectively. CD44S expression was positively correlated with YAP1 expression in these HCC tissues. In vitro experiments suggested that CD44S could positively regulate the expression of YAP1 and its target genes via the PI3K/Akt pathway in HCC cells. Moreover, CD44S is regulated by the YAP1/TEAD axis. These results reveal a novel positive feedback loop involving CD44S and YAP1, in which CD44S functions as both an upstream regulator and a downstream effector of YAP1 in HCC. This feedback loop might constitute a broadly conserved module for regulating cell proliferation and invasion during HCC tumorigenesis. Blocking this positive feedback loop that involves CD44S and YAP1 might represent a new approach for HCC treatment.

Overexpression of Yes-associated protein and its association with clinicopathological features of hepatocellular carcinoma: A meta-analysis

BACKGROUND

Yes-associated protein (YAP) overexpression is reported to be associated with risk of hepatocellular carcinoma (HCC) but current studies have not explored the relationship between YAP expression with HCC clinicopathological features.

METHODS

To assess these associations, a meta-analysis was performed which included four eligible studies including 391 HCC cases and 334 controls. There were eight eligible studies to investigate the association between YAP expression in HCC and clinicopathological features of liver cancer patients. Literature was obtained from PubMed, Embase, Wangfang and China National Knowledge Infrastructure.

RESULTS

Analysis indicated that YAP expression in HCC was greater than in adjacent non-tumour tissue (odds ratio [OR], 15.80, 95% confidence interval [CI], 10.53-23.70, P<.00001; heterogeneity=.30). YAP overexpression in HCC was significantly associated with vascular invasion (OR, 2.21, 95% CI, 11.64-2.97, P<.00001, heterogeneity=.10), less cellular differentiation (OR, 2.38, 95% CI, 1.61-3.51, P<.00001, heterogeneity=.333), tumours larger than 5 cm (OR, 2.52, 95% CI, 1.75-3.62, P<.00001; heterogeneity=.17) and TNM tumour stage I + II (OR, 0.44, 95% CI, 0.28-0.75, P=.00003, heterogeneity=.12).

CONCLUSIONS

Overexpression of YAP contributes to HCC formation, and its overexpression is associated with vascular invasion, low cellular differentiation tumours larger than 5 cm and TNM tumour stage III + IV.

Niu-Huang-Shen suppresses hepatocellular carcinoma cell growth and metastasis by regulating Yap1 expression

Hepatocellular carcinoma (HCC) is one of the most common cancers types. Niu-Huang-Shen (NHS), a Chinese medicine, has been reported to exert antipyretic, anti-inflammatory and vasodilatation effects. However, whether NHS has inhibitory effects on HCC cell phenotypes has remained elusive. In the present study, Cell Counting Kit-8, colony formation, fluorescence-activated cell sorting and Transwell assays were used to evaluate the effect of NHS on cell proliferation, migration and invasion. The results indicated that NHS suppressed cell proliferation and invasion, inhibited cell apoptosis, and induced cell cycle arrest. In addition, NHS significantly suppressed the mRNA and protein expression of Yes-associated protein (YAP). It was concluded that NHS downregulated YAP expression and inhibited the Hippo signaling pathway as well as HCC cell growth and invasion. NHS may be a novel potential therapeutic for HCC patients.

The correlation between poor prognosis and increased yes-associated protein 1 expression in keratin 19 expressing hepatocellular carcinomas and cholangiocarcinomas

Background

The Hippo pathway plays a vital role in liver regeneration and development by determining cellular lineage and regulating cell proliferation and apoptosis. In this study, we aimed to assess the role of the Hippo pathway in hepatic carcinogenesis and morphogenesis by examining Yes-associated protein 1 (YAP1) expression in the spectrum of hepatic carcinomas based on cellular lineage.

Methods

We examined 913 primary hepatic carcinomas, including hepatocellular carcinomas (HCCs), combined hepatocellular and cholangiocarcinomas (cHC-CCAs), intrahepatic cholangiocarcinomas (IHCCAs) and perihilar extrahepatic bile duct carcinomas (EHBCAs). Our study group was categorized into 8 disease groups, based on histological diagnosis and cytokeratin 19 (CK19) expression, and immunohistochemistry was used to detect and compare YAP1 expression levels between the groups. The eight disease groups we identified were: 1) CK19(−) HCC, 2) CK19(−) scirrhous HCC, 3) CK19(+) HCC, 4) stem cell feature of cHC-CCA, 5) classical cHC-CCA, 6) cholangiolocellular IHCCA, 7) non-cholangiolocellular IHCCA, and 8) EHBCA.

Results

Positive rates of YAP1 were the highest in the EHBCA group (21%). CK19(+) HCC and non-cholangiolocellular IHCCA groups also showed high expression levels (10% -11%), while the CK19 (−) HCC, CK19 (−) scirrhous HCC, cHC-CCA, and cholangiolocellular IHCCA groups showed low expression levels, ranging between 0% and 5%. Survival analysis, restricted to pT1 stage HCCs and IHCCAs, showed poor overall survival for YAP1(+) IHCCA patients (39 ± 17 vs. 109 ± 10 months, mean ± SD, log rank p-value 0.005). For HCCs, a trend of poor progression-free survival for YAP1(+) HCCs was observed (39 ± 18 vs. 81 ± 5 months, mean ± SD, log rank p-value 0.205)

Conclusions

YAP1 activation was more commonly found in CCAs than in pure HCCs. However, a differing pattern of YAP1 expression between cHC-CCAs and CK19(+) HCCs and the poor prognosis of YAP1 positive hepatic carcinomas suggests that YAP1 may have a preferential role in aggressive tumor behavior, rather than in the determination of cellular lineage in hepatic carcinomas.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3431-1) contains supplementary material, which is available to authorized users.

Angiomotin promotes the malignant potential of colon cancer cells by activating the YAP-ERK/PI3K-AKT signaling pathway

Colorectal cancer (CRC) is a leading cause of cancer-related deaths with an increasing incidence in China. The aberrant expression of angiomotin (AMOT) has been confirmed in a variety of tumors and can interact with Yes-associated protein (YAP) to either promote or suppress the progression of cancer. Unfortunately, its role in CRC remains poorly elucidated. Herein, higher levels of AMOT were observed in CRC cell lines. Upregulation of AMOT in LoVo cells markedly increased cell proliferation and apoptotic resistance to 5-fluorouracil. Moreover, its increase also promoted cell invasion and migration. Simultaneously, AMOT silencing markedly attenuated the growth and metastatic potential of HCT116 cells. Notably, AMOT upregulation promoted the activity of YAP by decreasing the expression of phosphorylated YAP and YAP in the cytoplasm and increasing YAP levels in the nucleus. Further mechanistic analysis corroborated that transfection with YAP siRNA notably diminished cell growth, invasion and migration in the AMOT‑overexpressing LoVo cells. Additionally, upregulation of AMOT induced the activation of the ERK and AKT pathways by YAP expression, both associated with the development of CRC. Collectively, these results suggest that AMOT may function as an oncogene in the progression of CRC by activating the YAP-ERK/PI3K-AKT signaling pathway. Therefore, this study presents a promising therapeutic target for CRC.

Long non-coding RNA H19 regulates FOXM1 expression by competitively binding endogenous miR-342-3p in gallbladder cancer

Background

Long non-coding RNA (lncRNA) H19 has been reported to involve in many kinds of human cancers and functions as an oncogene. Our previous study found that H19 was over-expressed in gallbladder cancer (GBC) and was shown to promote tumor development in GBC. However, the competing endogenous RNA (ceRNA) regulatory network involving H19 in GBC progression has not been fully elucidated. We aim to detect the role of H19 as a ceRNA in GBC.

Methods and Results

In this study, the expression of H19 and miR-342-3p were analyzed in 35 GBC tissues and matched normal tissues by using quantitative polymerase chain reaction (qRT-PCR). We demonstrated H19 was overexpressed and negatively correlated with miR-342-3p in GBC. By dual-luciferase reporter assays, RNA-binding protein immunoprecipitation (RIP) and RNA pull-down assays, we verified that H19 was identified as a direct target of miR-342-3p. QRT-PCR and Western-blotting assays demonstrated that H19 silencing down-regulated, whereas over-expression enhanced the expression of miR-342-3p targeting FOXM1 through competitively ‘sponging’ miR-342-3p. Furthermore, transwell invasion assays and cell cycle assays indicated that H19 knockdown inhibited both cells invasion and proliferation, but this effects was attenuated by co-transfection of siRNA-H19 and miR-342-3p inhibitor in GBC cells. In vivo, tumor volumes were decreased significantly in H19 silenced group compared to the control group, but was attenuated by co-transfection of shRNA-H19 and miR-342-3p inhibitor, which were stablely constructed through lenti-virus vector.

Conclusion

Our results suggest a potential ceRNA regulatory network involving H19 regulates FOXM1 expression by competitively binding endogenous miR-342-3p in GBC. This mechanism may contribute to a better understanding of GBC pathogenesis and provides potential therapeutic strategy for GBC.

The Clinical Significance and Potential Therapeutic Role of GPx3 in Tumor Recurrence after Liver Transplantation

BACKGROUND AND AIMS

Our previous study showed that small-for-size liver graft may provide favorable micro-environment for tumor growth. GPx3, an anti-oxidant, not only attenuates oxidative stress, but also suppresses liver tumor growth in our recent study. Here, we aimed to characterize the clinical significance and explore the functional role of GPx3 in HCC recurrence after liver transplantation.

METHODS

To explore the association between GPx3 expression and HCC invasiveness, a rat orthotopic liver transplantation model with tumor development was established. To investigate the clinical relevance of GPx3, 105 HCC patients who underwent liver transplantation were recruited. The suppressive role of GPx3 in HCC cells was studied using wound healing, Matrigel invasion assay and lung metastasis model. The real-time intravital imaging system was applied to directly visualize the tumor cells invasion in a living animal. The underlying mechanism was further explored.

RESULTS

GPx3 was identified as a down-regulated protein in small-for-size liver graft and significantly associated with invasive phenotype of tumor growth in a rat model. Plasma GPx3 was significantly lower in small-for-size graft group post-transplantation (day1: 33 vs 1147; day3: 3209 vs 4459; day7: 303 vs 2506; mU/mL, P<0.05) in rat model. Clinically, the plasma GPx3 was significantly lower in the recipients with HCC recurrence post-transplantation (day1: 4.16 vs 8.99 µg/mL, P<0.001; day7: 3.86 vs 9.99 µg/mL, P<0.001). Furthermore, lower plasma GPx3 was identified as an independent predictor (HR=4.528, P=0.046) for poor overall survival post-transplantation. Over-expression of GPx3 significantly suppressed migration, invasiveness and metastasis of HCC cells. Real-time intravital imaging showed that GPx3 significantly suppressed HCC invasiveness in a live animal. GPx3 suppressed the tumor invasiveness through inhibition of JNK-cJun-MMP2 pathway.

CONCLUSION

GPx3 may possess prognostic and therapeutic value for HCC patients after liver transplantation.

Serologic and molecular biomarkers for recurrence of hepatocellular carcinoma after liver transplantation: A systematic review and meta-analysis

INTRODUCTION

Recurrence after liver transplantation (LT) for hepatocellular carcinoma (HCC) is a major cause of mortality. Knowledge on biomarkers may contribute to better surveillance based on the patients' risk of recurrence. Reviewing the literature, we aimed to identify serological and molecular biomarkers for recurrence of hepatocellular carcinoma after liver transplantation.

METHODS

A literature search was performed in the databases PubMed and Scopus to identify observational studies evaluating serological or molecular biomarkers for recurrence of HCC after LT using adjusted analysis to correct for confounding.

RESULTS

Of 502 records, 69 mainly retrospective studies were included with a total of 15,213 patients. Of these, 41 studies were suitable for meta-analyses, which showed that the serum markers pre-transplant α-fetoprotein (AFP) (hazard ratio (HR) 2.69 [2.08-3.47]), pre-transplant des-gamma-carboxy prothrombin (DCP) (HR 5.99 [3.27-10.98]), and allelic imbalance in microsatellites in DNA of tumor tissue (HR 13.49 [3.17-57.30]) were related to recurrence.

CONCLUSIONS

AFP, DCP and allelic imbalance in microsatellites may be used to predict recurrence. Together with other modalities, biomarkers may be used in future transplantation criteria to optimize selection of suitable patients.

CIZ1 interacts with YAP and activates its transcriptional activity in hepatocellular carcinoma cells

Dysregulation of Hippo-Yes-associate protein (YAP) signaling has important roles in the tumorigenesis of hepatocellular carcinoma (HCC). Our previous studies have shown that Cip1 interacting zinc finger protein 1 (CIZ1) activated YAP signaling in the HCC cells and promoted the growth and migration of cancer cells. However, the mechanisms for the activation of YAP signaling by CIZ1 are unknown. In this study, it was found that CIZ1 interacted with the transcriptional factor YAP in HCC cells. The nuclear matrix anchor domain of CIZ1 is responsible for its interaction with YAP. Moreover, CIZ1 enhanced the interaction between YAP and TEAD. Knocking down the expression of CIZ1 impaired the transcriptional activity as well as the biological functions of YAP. Taken together, our study demonstrated that CIZ1 is a positive regulator of YAP signaling, and CIZ1 might be a therapeutic target for HCC.

Expression of P53 and HSP70 in Chronic Hepatitis, Liver Cirrhosis, and Early and Advanced Hepatocellular Carcinoma Tissues and Their Diagnostic Value in Hepatocellular Carcinoma: An Immunohistochemical Study

Background

Tumor protein (P53) and heat shock protein 70 (HSP70) play key roles in chronic liver diseases. This study aimed to characterize P53 and HSP70 expression in chronic hepatitis (CH), liver cirrhosis (LC), early and advanced HCC, and to analyze their diagnostic value in hepatocellular carcinoma (HCC).

Material/Methods

Immunohistochemical staining was conducted to evaluate the expression of P53 and HSP70 in 200 human liver tissue specimens, with advanced HCC (n=80), early HCC (n=30), CH (n=30), LC (n=30), and Controls (n=30).

Results

P53 expression levels were lower in LC than those of HCC, but remained on par with those of CH and Controls. HSP70 expression levels were higher in HCC than those of LC, CH, and Controls. The sensitivity and specificity for HCC diagnosis were: 50.9% and 98.9% for P53, and 78.2 and 77.8% for HSP70, respectively. The sensitivity and specificity of different combinations were: 95.5% and 85.5% with either P53 or HSP70 being positive, and 33.6% and 98.9% if both were positive. Among the differentiation stages marked low, intermediate, and high in HCC, the P53 positive rate was higher in the low than in the intermediate, which was higher than that in the high. HSP70 positive rate was higher in the low and the intermediate than in the high, but no obvious changes were found between the low and the intermediate.

Conclusions

P53 and HSP70 could be potential biomarkers for HCC diagnosis, and proper combinations of these 2 markers could improve diagnostic accuracy.