Functions In Hepatocellular Carcinoma Progression Research Articles

S100A9 Derived from Chemoembolization-Induced Hypoxia Governs Mitochondrial Function in Hepatocellular Carcinoma Progression.

Transarterial chemoembolization (TACE) is the major treatment for advanced hepatocellular carcinoma (HCC), but it may cause hypoxic environment, leading to rapid progression after treatment. Here, using high‐throughput sequencing on different models, S100 calcium binding protein A9 (S100A9) is identified as a key oncogene involved in post‐TACE progression. Depletion or pharmacologic inhibition of S100A9 significantly dampens the growth and metastatic ability of HCC. Mechanistically, TACE induces S100A9 via hypoxia‐inducible factor 1α (HIF1A)‐mediated pathway. S100A9 acts as a scaffold recruiting ubiquitin specific peptidase 10 and phosphoglycerate mutase family member 5 (PGAM5) to form a tripolymer, causing the deubiquitination and stabilization of PGAM5, leading to mitochondrial fission and reactive oxygen species production, thereby promoting the growth and metastasis of HCC. Higher S100A9 level in HCC tissue or in serum predicts a worse outcome for HCC patients. Collectively, this study identifies S100A9 as a key driver for post‐TACE HCC progression. Targeting S100A9 may be a promising therapeutic strategy for HCC patients.

LncRNA n339260 functions in hepatocellular carcinoma progression via regulation of miRNA30e-5p/TP53INP1 expression.

Currently, the molecular mechanism of the interaction between lncRNAs and microRNAs (miRNAs) and the target of miRNAs in tumor vasculogenic mimicry (VM) formation have not been clarified. Our aim is to study the interaction between lncRNA n339260 and miRNA30e-5p in the formation of VM. Animal xenografts were established, 104 hepatocellular carcinoma (HCC) patients' frozen tissues were obtained and HCC cells in vitro were used to observe the role of n339260 in HCC progression. In vivo experiment showed lncRNA n339260 promoted tumor growth and VM formation. LncRNA n339260 and miRNA30e-5p were found to be associated with VM formation, metastasis and survival time in HCC patients. In vitro experiment showed that LncRNA n339260 could inhibit miRNA30e-5p expression and TP53INP1 was found to be the downstream targets of miRNA30e-5p. Snail, MMP2, MMP9, VE-cadherin, vimentin and N-cadherin overexpression and the downregulation of TP53INP1 and E-cadherin were observed in HCCLM3 and HepG2 cells overexpressing lncRNA n339260 or in cells with decreased expression of miRNA30e-5p. LncRNA n339260 promotes the development of VM, and lncRNA n339260 may enhance Snail expression by decreasing the expression of miRNA30e-5p, thereby reducing TP53INP1 expression. Therefore, a potential lncRNA n339260- miRNA30e-5p- TP53INP1 regulatory axis was associated with HCC progression.

Identification of key long noncoding RNAs and their biological functions in hepatocellular carcinoma

Long noncoding RNAs (lncRNAs) are vital regulators in tumorigenesis and metastasis. However, the pathological role of lncRNAs in hepatocellular carcinoma (HCC) is still unclear. In this study, we filtered out three lncRNAs from The Cancer Genome Atlas (TCGA) data that were screened for basic expression and clinical research. We selected lncRNA-NEAT1 for further study to explore its function in HCC progression and its regulatory mechanism. We identified three differentially expressed lncRNAs (DElncRNAs) in tumor and adjacent normal tissues from the TCGA library using data mining methods: lncRNA-NEAT1, lncRNA-MAGI2-AS3 and lncRNA-HCG11. Their basic expression levels were detected by qPCR. Then, we selected lncRNA-NEAT1 as a potentially important lncRNA to verity its biological function and mechanism in HCC cell lines. lncRNA-NEAT1, lncRNA-MAGI2-AS3 and lncRNA-HCG11 were overexpressed in liver cancer tissues and cell lines. We found that silencing NEAT1 in vitro can inhibit the proliferation of HuH-7 and Li-7 cells, inhibit cell migration, and induce apoptosis as well as significantly increase the level of miR-16-5p. We also confirmed that miR-16-5p has a significant correlation with Bcl-2. When NEAT1 is silenced, the expression of Bcl-2 decreases. Inhibiting miR-16-5p can restore Bcl-2 to its original level. We conclude that miR-16-5p1/lncRNA NEAT1 plays a crucial role in regulating the delivery of Bcl-2 in HCC. Overall, the miR-16-5p/lncRNA-NEAT1/Bcl-2 signaling axis may be a promising target for HCC treatment.

SMYD3 promotes hepatocellular carcinoma progression by methylating S1PR1 promoters

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. SET and MYND domain-containing protein 3 (SMYD3) has been shown to promote the progression of various types of human cancers, including liver cancer; however, the detailed molecular mechanism is still largely unknown. Here, we report that SMYD3 expression in HCC is an independent prognostic factor for survival and promotes the proliferation and migration of HCC cells. We observed that SMYD3 upregulated sphingosine-1-phosphate receptor 1 (S1PR1) promoter activity by methylating histone 3 (H3K4me3). S1PR1 was expressed at high levels in HCC samples, and high S1PR1 expression was associated with shorter survival. S1PR1 expression was also positively correlated with SMYD3 expression in HCC samples. We confirmed that SMYD3 promotes HCC cell growth and migration in vitro and in vivo by upregulating S1PR1 expression. Further investigations revealed that SMYD3 affects critical signaling pathways associated with the progression of HCC through S1PR1. These findings strongly suggest that SMYD3 has a crucial function in HCC progression that is partially mediated by histone methylation at the downstream gene S1PR1, which affects key signaling pathways associated with carcinogenesis and the progression of HCC.

Upregulation of miR-1266-5p serves as a prognostic biomarker of hepatocellular carcinoma and facilitates tumor cell proliferation, migration and invasion.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. This study aimed to analyze the prognostic value of microRNA-1266-5p (miR-1266-5p) in HCC patients and investigate its biological function in HCC progression. The expression of miR-1266-5p in tissues and cells was measured by quantitative real-time PCR (qRT-PCR). Cell counting kit-8 (CCK-8) assay was used to detect HCC cell proliferation. Transwell assay was performed to evaluate the migration and invasion of HCC cells. Kaplan-Meier methods and Cox regression analysis were used to assess the prognostic value of miR-1266-5p in HCC patients. The relationship between miR-1266-5p and DAB2IP was evaluated by luciferase reporter assay. Relative expression of miR-1266-5p in tumor tissues, tissues from patients with advanced TNM stage (III-IV) and HCC cells was increased compared with that in corresponding control group. MiR-1266-5p expression was significantly associated with tumor size and TNM stage in HCC patients. Elevated expression of miR-1266-5p was associated with poor prognosis of HCC patients and served as an independent prognostic factor for HCC patients. Overexpression of miR-1266-5p significantly promoted, while miR-1266-5p knockdown significantly inhibited the proliferation, migration and invasion of HCC cells. DAB2IP could directly bind to the miR-1266-5p. Our findings indicated that elevated expression of miR-1266-5p can predict the poor prognosis of HCC patients, and promotes the proliferation, migration and invasion of HCC cells. Therefore, we predict that miR-1266-5p may be a novel biomarker and therapeutic target for the treatment of HCC.

S100 calcium-binding protein A9 from tumor-associated macrophage enhances cancer stem cell-like properties of hepatocellular carcinoma.

Tumor-associated macrophages (TAMs) are crucial components of the tumor microenvironment. They play vital roles in hepatocellular carcinoma (HCC) progression. However, the interactions between TAMs and HCC cells have not been fully characterized. In this study, TAMs were induced using human monocytic cell line THP-1 cells in vitro to investigate their functions in HCC progression. S100 calcium-binding protein A9 (S100A9), an inflammatory microenvironment-related secreted protein, was identified to be significantly upregulated in TAMs. S100A9 expression in tumor tissues was associated with poor survival of HCC patients. It could enhance the stem cell-like properties of HepG2 and MHCC-97H cells by activating nuclear factor-kappa B signaling pathway through advanced glycosylation end product-specific receptor in a Ca2+ -dependent manner. Furthermore, we found that, after treatment with S100A9, HepG2 and MHCC-97H cells recruited more macrophages via chemokine (CC motif) ligand 2, which suggests a positive feedback between TAMs and HCC cells. Taken together, our findings reveal that TAMs could upregulate secreted protein S100A9 and enhance the stem cell-like properties of HCC cells and provide a potential therapeutic target for combating HCC.

Neurotrophin 3 hinders the growth and metastasis of hepatocellular carcinoma cells*

Abstract Objective Neurotrophin 3 (NTF3) is involved in numerous biological processes; however, its role in hepatocellular carcinoma (HCC) is not well studied. This study investigated NTF3 function in HCC progression and revealed its underlying molecular mechanisms. Methods The prognostic relevance of NTF3 was determined through a bioinformatical analysis of publicly available TCGA data. Immunohistochemistry of HCC biopsies was performed to explore the expression of NTF3. Cell growth and proliferation were analyzed using a Cell Counting Kit-8 (CCK-8) assay. Cell invasion and migration were analyzed using Boyden Transwell and wound healing assays. Protein expression and mRNA levels were evaluated through immunoblotting and quantitative polymerase chain reaction (qPCR). Cell apoptosis was evaluated with flow cytometry. Results NTF3 expression was significantly lower in HCC tissues than in adjacent non-tumor tissues. Low NTF3 expression was significantly associated with decreased patient survival and specific clinicopathological features. NTF3 overexpression reduced the proliferation, migration, and invasion abilities of HCC cell lines. Conclusion Decreased expression of NTF3 is associated with poor prognosis in HCC patients, likely due to its action in promoting HCC cell proliferation, migration, and invasion. Our findings provide a novel understanding into the pathogenesis of HCC and the role of NTF3 in tumor progression, suggesting that targeting NTF3 has potential therapeutic and diagnostic value for HCC.

MiR-885-5p Negatively Regulates Warburg Effect by Silencing Hexokinase 2 in Liver Cancer

Growing tumor cells possess a distinct metabolic phenomenon that allows them to preferentially utilize glucose through aerobic glycolysis, which is referred to as the “Warburg effect.” Accumulating evidence suggests that microRNAs (miRNAs) could regulate such metabolic reprogramming. Our microarray analysis and quantitative real-time PCR validation revealed that miR-885-5p was strongly downregulated in hepatocellular carcinoma (HCC) tissues and cell lines. To investigate miR-885-5p’s biological functions in HCC progression, malignant phenotypes were analyzed in different types of hypoxic model and indicated that overexpression of miR-885-5p significantly inhibited HCC cell proliferation and migration and induced apoptosis in vitro and tumor growth in vivo. Subsequent investigations of whether miR-885-5p regulated the glycometabolic activity of cancer cells demonstrated that forced expression of miR-885-5p in SMMC-7721 cells significantly reduced glucose uptake and lactate production by repressing several key enzymes related to glycolysis. Particularly, miR-885-5p directly targets the 3′ UTR of hexokinase 2 (HK2), which is a key enzyme that catalyzes the irreversible first step of glycolysis and associates with poor patient outcomes. The miR-885-5p/HK2 axis strongly links aerobic glycolysis to carcinogenesis and may become a promising therapeutic target and prognostic predictor for HCC patients.

Abstract 4443: Targeting E3 ligase PJA1 via TGF-β pathway in hepatocellular carcinoma

Abstract Background: RING-finger E3 ligases are instrumental in the regulation of inflammatory cascades, apoptosis, and cancer. However, their roles are relatively unknown for specific pathways such as TGF-β/Smad signaling that when disrupted, drive hepatocellular carcinoma (HCC). We, therefore, analyzed the TCGA database for the TGF-β pathway associated 22 E3 ligases, and identified mRNA alterations in 55% of tumors, most prominently for UCHL5 (16.4%), PJA (12.7%), WWP2 (11.8%), SKP2 (9.1%), SMURF1 and SMURF2 (8.2 and 9.1%, respectively), ITCH (6.4%) and KEAP1 (6.4%). We previously uncovered increased PJA1 expression with loss of TGF-β substrates Smad3 and β2SP in TGF-β deficient mice (β2SP+/-/Smad3+/- mice), which spontaneously develop characteristics of a human stem cell syndrome, and HCC by 12-15 months. Here, we report PJA1 oncogenic function in HCC progression. HCC. Methods & Results: (1) Analyses of primary HCC datasets (91 cases) reveal increased PJA1 correlates with decreased levels of TGF-β/Smad3 and their regulated genes including Smad8 and TGFBR3. (2) To better understand the implications of PJA1-mediated deregulation of Smad3-promoted transcription in HCC, we compared transcriptomes of HepG2 cells silenced by PJA1 shRNA or treated with TGF-β: 1,584 genes including c-FOS were co-up-regulated and 1,279 genes including TERT were co-down-regulated. PJA1 expression in HCC was negatively associated with c-FOS and SERPINE1 expression. (3) PJA1 interacts with the Smad3 MH2 and Linker domains and multiple domains of β2SP to promote ubiquitin-mediated phosphor-Smad3 degradation in a TGF-β dependent manner, resulting in decreased TGF-β target gene activity. (4) We found that PJA1 expression in HCC is negatively associated with c-FOS and SERPINE1 expression. (5) Overexpression of a RING-domain-deleted PJA1 mutant reduced the proliferation rate in HCC cells and PJA1 knockdown significantly decreased anchorage-independent growth and tumorigenicity of HCC cells. (6) Our results also demonstrate that PJA1 promotes liver cancer stem cell formation in Smad3+/- mice. Conclusions: This study demonstrates that loss of expression of β2SP and Smad3 through PJA1 could play an important role in HCC progression and that PJA1 is a potential novel therapeutic target for this lethal disease. Citation Format: Kazufumi Ohshiro, Jian Chen, Wilma Jogunoori, Chu-Xia Deng, Bibhuti Mishra, Shulin Li, Lopa Mishra. Targeting E3 ligase PJA1 via TGF-β pathway in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4443.

Silencing of long noncoding RNA HOXD-AS1 inhibits proliferation, cell cycle progression, migration and invasion of hepatocellular carcinoma cells through MEK/ERK pathway.

Accumulating findings reveal that long noncoding RNAs (lncRNAs) as crucial regulatory molecules serve vital functions in the progression of hepatocellular carcinoma (HCC). This study aims to investigate the biological roles and mechanisms of lncRNA HOXD cluster antisense RNA 1 (HOXD-AS1) in HCC cells based on transcriptome analysis. The Cancer Genome Atlas data analysis and experimental validation showed that HOXD-AS1 was increased in HCC tissues/cell lines and positively relevant to histologic grade. The subcellular localization results indicated HOXD-AS1 was dispersed both in the nucleus as well as the cytoplasm of HCC cells. In vitro loss-of-function experiments revealed that silencing of HOXD-AS1 could dramatically suppress the proliferation, migration, and invasion, and induce S or/and G2/M phase cell cycle arrest as well as apoptosis of Bel-7402 and MHCC97H cells accompanying the changes in expression levels of cyclin B1, cyclin D1, BCL-2, BAX, and MMP2. In vivo assay also showed that HOXD-AS1 silencing could markedly reduce xenograft tumor volume and weight of HCC cells. Transcriptome and bioinformatic analysis indicated that a total of 1103 genes were significantly altered by HOXD-AS1 silencing, of which 132 genes exhibited a significant correlation with HOXD-AS1 expression in HCC tissues. Gene Ontology (GO) enrichment analysis revealed differentially expressed genes were remarkably enriched in several cancer-related biological processes (cell proliferation, cell cycle, apoptosis, migration, angiogenesis, and hypoxic response). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that HOXD-AS1 has the potential to affect p53, tumor necrosis factor (TNF), mitogen-activated protein kinase (MAPK) pathway, and Western blot results further validated that HOXD-AS1 silencing could inhibit the MEK/ERK pathway in Bel-7402 cells. Collectively, HOXD-AS1, as an oncogenic lncRNA, might exert crucial functions in HCC progression and serve as a potential diagnostic biomarker and therapeutic target for HCC.

MicroRNA-376c-3p Facilitates Human Hepatocellular Carcinoma Progression via Repressing AT-Rich Interaction Domain 2.

Hepatocellular carcinoma (HCC), accounting for approximately 90% of liver cancer, is the most lethal malignant tumors in the world. Large amount of evidence indicate that microRNAs (miRNAs) contribute to the tumorigenesis and progression of HCC. Among them, miR-376c-3p was recently identified as a tumor-related miRNA and is up-regulated in HBV-related HCC. But, the clinical significance of miR-376c-3p and its biological function in HCC progression are still unclear. Here, we confirmed that miR-376c-3p expression level in HCC was markedly higher than that in noncancerous tissues. Up-regulation of miR-376c-3p was detected in four different HCC cell lines. High miR-376c-3p expression correlated with poor prognostic features, such as large tumor size and venous infiltration. Follow-up data indicated that high miR-376c-3p level evidently correlated with poor clinical outcomes of HCC patients. Moreover, knockdown of miR-376c-3p repressed HCC cell growth, migration and invasion in vitro. miR-376c-3p overexpression facilitated these malignant behaviors of Bel-7402 cells. Mechanistically, miR-376c-3p posttranscriptionally repressed ARID2 expression by directly interacting with its 3'-UTR. Furthermore, an obvious negative correlation between miR-376c-3p and ARID2 mRNA expression in HCC tissues was confirmed. Notably, miR-376c-3p knockdown suppressed HCC growth and metastasis in nude mice. Gain-of-function experiments showed that ARID2 inhibited cell growth and mobility of Hep3B cells. Subsequently, ARID2 knockdown rescued miR-376c-3p silencing attenuated Hep3B cell proliferation and mobility. Our results suggest that miR-376c-3p exerts an oncogenic role in HCC progression.

Prospero-related homeobox 1 drives angiogenesis of hepatocellular carcinoma through selectively activating interleukin-8 expression.

We have identified PROX1 as a crucial promoter of HCC angiogenesis; our study provides an insight into PROX1's function in HCC progression and the potential therapeutic application of anti-IL-8 antibody in high PROX1 expression HCC patients. (Hepatology 2017;66:1894-1909).

T-cell immunoglobulin mucin-3 as a potential inducer of the epithelial-mesenchymal transition in hepatocellular carcinoma.

T-cell immunoglobulin mucin (TIM)-3 is an important member of the TIM gene family, which was thought to contribute to the progression of numerous types of cancer, including hepatocellular carcinoma (HCC); however, the mechanism underlying TIM-3 functions in HCC progression has not yet been extensively investigated. The present study aimed to investigate the function of TIM-3 in the metastasis of HCC and to determine whether the alteration of TIM-3 expression levels regulated the epithelial-mesenchymal transition (EMT) occurrence of HCC, using epithelial (E)-cadherin, neuronal (N)-cadherin, matrix metallopeptidase-9 (MMP-9), Twist 1, Slug, Snail, and Smad as EMT biomarkers. The results demonstrated that upregulation of TIM-3 using TIM-3 lentiviral activation particles (5 µl) increased cell migration and invasion, which was decreased in TIM-3 short interfering RNA-infected cells (10 µM, 3 µl) correspondingly. SMMC-7721 HCC cells were used as the control. EMT was aggravated in TIM-3 upregulated SMMC-7721 cells, which was attenuated in the TIM-3 interference group, accompanied by an alteration of E-cadherin, N-cadherin, MMP-9, Twist 1, Slug, Snail and Smad expression levels. The data presented suggests that TIM-3 serves an essential role in the metastasis of HCC, the mechanism of which was associated with EMT occurrence. Interference of TIM-3 is expected to be an effective means to prevent and control EMT, and further the metastasis of HCC.

Glypican-3: A promising biomarker for hepatocellular carcinoma diagnosis and treatment.

Liver cancer is the second leading cause of cancer-related deaths, and hepatocellular carcinoma (HCC) is the most common type. Therefore, molecular targets are urgently required for the early detection of HCC and the development of novel therapeutic approaches. Glypican-3 (GPC3), an oncofetal proteoglycan anchored to the cell membrane, is normally detected in the fetal liver but not in the healthy adult liver. However, in HCC patients, GPC3 is overexpressed at both the gene and protein levels, and its expression predicts a poor prognosis. Mechanistic studies have revealed that GPC3 functions in HCC progression by binding to molecules such as Wnt signaling proteins and growth factors. Moreover, GPC3 has been used as a target for molecular imaging and therapeutic intervention in HCC. To date, GPC3-targeted magnetic resonance imaging, positron emission tomography, and near-infrared imaging have been investigated for early HCC detection, and various immunotherapeutic protocols targeting GPC3 have been developed, including the use of humanized anti-GPC3 cytotoxic antibodies, treatment with peptide/DNA vaccines, immunotoxin therapies, and genetic therapies. In this review, we summarize the current knowledge regarding the structure, function, and biology of GPC3 with a focus on its clinical potential as a diagnostic molecule and a therapeutic target in HCC immunotherapy.

Apoptosis signal-regulating kinase 1 mediates the inhibitory effect of hepatocyte nuclear factor-4α on hepatocellular carcinoma.

Previous studies provided substantial evidence of a striking suppressive effect of hepatocyte nuclear factor 4α (HNF4α) on hepatocellular carcinoma (HCC). Apoptosis signal-regulating kinase 1 (ASK1) is involved in death receptor-mediated apoptosis and may acts as a tumor suppressor in hepatocarcinogenesis. However, the status and function of ASK1 during HCC progression are unclear. In this study, we found that HNF4α increased ASK1 expression by directly binding to its promoter. ASK1 expression was dramatically suppressed and correlated with HNF4α levels in HCC tissues. Reduced ASK1 expression was associated with aggressive tumors and poor prognosis for human HCC. Moreover, ASK1 inhibited the malignant phenotype of HCC cells in vitro. Intratumoral ASK1 injection significantly suppressed the growth of subcutaneous HCC xenografts in nude mice. More interestingly, systemic ASK1 delivery strikingly inhibited the growth of orthotopic HCC nodules in NOD/SCID mice. In addition, inhibition of endogenous ASK1 partially reversed the suppressive effects of HNF4α on HCC. Collectively, this study highlights the suppressive effect of ASK1 on HCC and its biological significance in HCC development. These outcomes broaden the knowledge of ASK1 function in HCC progression, and provide a novel potential prognostic biomarker and therapeutic target for advanced HCC.

Overexpression of chaperonin containing TCP1, subunit 3 predicts poor prognosis in hepatocellular carcinoma.

To investigate the value of chaperonin containing TCP1, subunit 3 (CCT3) to predict the prognosis of patients with hepatocellular carcinoma (HCC) and determine its function in HCC progression. CCT3 expression levels were examined in human non-cancerous liver tissues and a variety of HCC cell lines by quantitative real-time PCR and immunoblotting. CCT3 expression was suppressed by small interfering RNA. The effects of reducing CCT3 expression in HCC cells were tested. The 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) assay, cell counting experiment, cell cycle assay, apoptosis assay and invasion assay were employed to evaluate cell functions in vitro. Immunohistochemistry was performed on HCC specimens. In addition, CCT3 expression in HCC specimens was also assessed at the protein and mRNA level. Associations between clinicopathological characteristics and prognosis were analyzed, along with the possible mechanisms involved in CCT3's function in HCC progression. The expression levels of CCT3 mRNA and protein were upregulated in HCC cell lines in contrast to adjacent non-cancerous tissues. Reducing CCT3 expression not only suppressed cell proliferation in cell counts, MTT assay, cell cycle assay and induced cell apoptosis (P < 0.05 vs negative control), but also inhibited the tumor cell invasion capacity in vitro (P < 0.01 vs negative control). Overexpression of CCT3 in the nuclei of cancer cells in HCC specimens (58 of 104 patients, 55.8%) was associated with poor prognosis in HCC patients (3-year survival rate, 55.5% vs 84.2%, P = 0.020) after hepatectomy. Mechanistic analyses showed that signal transducer and activator of transcription 3 (STAT3) activation was decreased even when stimulated by interleukin-6 after knocking down CCT3 in the HepG2 cell line. Overexpression of CCT3 in the nuclei of cancerous cells is associated with HCC progression. CCT3 may be a target that affects the activation of STAT3 in HCC.

Overexpression of brachyury contributes to tumor metastasis by inducing epithelial-mesenchymal transition in hepatocellular carcinoma.

AimsBrachyury overexpression has been reported in various human malignant neoplasms, but its expression and function in hepatocellular carcinoma progression and metastasis remains unknown. The present study aimed to evaluate the critical role of Brachyury in HCC metastasis.MethodsThe expression of Brachyury in human HCC (SMMC7721, HepG2, FHCC98, and Hep3B) and control cell lines was analyzed using quantitative reverse-transcriptase polymerase chain reaction and immunoflourence methods. Cancerous tissues collected from patients with HCC (n = 112) were analyzed using immunohistochemical method; a microarray analysis of HCC tissues was performed to explore the clinicopathological variables of HCC. The migratory and invasive capacities of Brachyury-SMMC7721 and Brachyury-HepG2 transfected cells were evaluated using in vitro scratch wound healing and Matrigel invasion assays, respectively. Further, six-week-old male BALB/c nude mice (n = 10) model was used in vivo assay.ResultsElevated expression of Brachyury was detected in HCCs (62.5%) compared with that in adjacent nontumorous tissues. Clinicopathological analysis revealed a close correlation of Brachyury expression with distant metastasis and poor prognosis of HCC. Overexpression of Brachyury promoted epithelial-mesenchymal transition (EMT) and metastasis of HCC cells in vitro and in vivo. Brachyury overexpression enhanced Akt activation by inhibiting phosphatase and tensin homolog (PTEN), which led to subsequent stabilization of Snail, a critical EMT mediator.ConclusionThe study findings suggest that elevated Brachyury facilitates HCC metastasis by promoting EMT via PTEN/Akt/Snail-dependent pathway. Brachyury plays a pivotal role in HCC metastasis and may serve as a novel prognostic biomarker and therapeutic target.

Proteinase-activated receptor 1- and 4-promoted migration of Hep3B hepatocellular carcinoma cells depends on ROS formation and RTK transactivation.

There is growing evidence for a role of proteinase-activated receptors (PARs), a subfamily of G protein-coupled receptors, in cancer. We have previously shown that PAR1 and PAR4 are able to promote the migration of hepatocellular carcinoma (HCC) cells suggesting a function in HCC progression. In this study, we assessed the underlying signalling mechanisms. Using Hep3B liver carcinoma cells, RTK activation was assessed by Western blot employing phospho-RTK specific antibodies, ROS level were estimated by H2DCF-DA using confocal laser scanning microscopy, and measurement of PTP activity was performed in cell lysates using 6,8-difluoro-4-methylumbelliferyl phosphate (DiFMUP) as a substrate. Thrombin, the PAR1 selective agonist peptide TFLLRN-NH2 (PAR1-AP), and the PAR4 selective agonist peptide, AYPGKF-NH2 (PAR4-AP), induced a significant increase in Hep3B cell migration that could be blocked by inhibitors targeting formation of reactive oxygen species (ROS), or activation of hepatocyte-growth factor receptor (Met), or platelet-derived growth factor receptor (PDGFR), respectively. The involvement of these intracellular effectors in PAR1/4-initiated migratory signalling was further supported by the findings that individual stimulation of Hep3B cells with the PAR1-AP and the PAR4-AP induced an increase in ROS production and the transactivation of Met and PDGFR. In addition, PAR1- and PAR4-mediated inhibition of total PTP activity and specifically PTP1B. ROS inhibition by N-acetyl-L-cysteine prevented the inhibition of PTP1B phosphatase activity induced by PAR1-AP and the PAR4-AP, but had no effect on PAR1/4-mediated activation of Met and PDGFR in Hep3B cells. Collectively, our data indicate that PAR1 and PAR4 activate common promigratory signalling pathways in Hep3B liver carcinoma cells including activation of the receptor tyrosine kinases Met and PDGFR, the formation of ROS and the inactivation of PTP1B. However, PAR1/4-triggered Met and PDGFR transactivation seem to be mediated independently from the ROS-PTP1B signalling module.

Novel roles of Vmp1: Inhibition metastasis and proliferation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most deadly human cancers because of its high incidence of metastasis. Despite extensive efforts, therapies against metastasis of HCC remain underdeveloped. Vacuole membrane protein 1 (Vmp1) was recently identified to be involved in cancer-relevant processes; however, its expression, clinical significance and biological function in HCC progression are still unknown. Therefore, we evaluated the expression of Vmp1 in human HCC specimens. To functionally characterize Vmp1 in HCC, we upregulated its expression in HCCLM3 cells using a plasmid transfection approach, following which both in vitro and in vivo models were used to elucidate its role. A significant downregulation of Vmp1 was found in human HCC tissues and closely correlated with multiple tumor nodes, absence of capsular formation, vein invasion and poor prognosis of HCC. Such expression was verified with HCC cell lines including HepG2, MHCC97-L and HCCLM3, and the Vmp1 expression levels negatively correlated with metastatic potential. Interestingly, upregulation of Vmp1 significantly affects proliferation, migration, invasion and adhesion of HCCLM3 cells. Using a mouse model, we demonstrated that upregulation of Vmp1 was associated with suppression of growth and pulmonary metastases of HCC. Therefore, our data suggest Vmp1 is a novel prognostic marker and potential therapeutic target for metastasis of HCC.

Cyclin G1–mediated epithelial-mesenchymal transition via phosphoinositide 3-kinase/Akt signaling facilitates liver cancer progression

Cyclin G1 deficiency is associated with reduced incidence of carcinogen-induced hepatocellular carcinoma (HCC), but its function in HCC progression remains obscure. We report a critical role of cyclin G1 in HCC metastasis. Elevated expression of cyclin G1 was detected in HCCs (60.6%), and its expression levels were even higher in portal vein tumor thrombus. Clinicopathological analysis revealed a close correlation of cyclin G1 expression with distant metastasis and poor prognosis of HCC. Forced expression of cyclin G1 promoted epithelial-mesenchymal transition (EMT) and metastasis of HCC cells in vitro and in vivo. Cyclin G1 overexpression enhanced Akt activation through interaction with p85 (regulatory subunit of phosphoinositide 3-kinase [PI3K]), which led to subsequent phosphorylation of glycogen synthase kinase-3β (GSK-3β) and stabilization of Snail, a critical EMT mediator. These results suggest that elevated cyclin G1 facilitates HCC metastasis by promoting EMT via PI3K/Akt/GSK-3β/Snail-dependent pathway. Consistently, we have observed a significant correlation between cyclin G1 expression and p-Akt levels in a cohort of HCC patients, and found that combination of these two parameters is a more powerful predictor of poor prognosis. Cyclin G1 plays a pivotal role in HCC metastasis and may serve as a novel prognostic biomarker and therapeutic target.