Aggressive Hepatocellular Carcinoma Research Articles

Modularity of the metabolic gene network as a prognostic biomarker for hepatocellular carcinoma.

Abnormal metabolism is an emerging hallmark of cancer. Cancer cells utilize both aerobic glycolysis and oxidative phosphorylation (OXPHOS) for energy production and biomass synthesis. Understanding the metabolic reprogramming in cancer can help design therapies to target metabolism and thereby to improve prognosis. We have previously argued that more malignant tumors are usually characterized by a more modular expression pattern of cancer-associated genes. In this work, we analyzed the expression patterns of metabolism genes in terms of modularity for 371 hepatocellular carcinoma (HCC) samples from the Cancer Genome Atlas (TCGA). We found that higher modularity significantly correlated with glycolytic phenotype, later tumor stages, higher metastatic potential, and cancer recurrence, all of which contributed to poorer prognosis. Among patients with recurred tumors, we found the correlation of higher modularity with worse prognosis during early to mid-progression. Furthermore, we developed metrics to calculate individual modularity, which was shown to be predictive of cancer recurrence and patients’ survival and therefore may serve as a prognostic biomarker. Our overall conclusion is that more aggressive HCC tumors, as judged by decreased host survival probability, had more modular expression patterns of metabolic genes. These results may be used to identify cancer driver genes and for drug design.

Hepatocellular carcinoma-targeting oncolytic adenovirus overcomes hypoxic tumor microenvironment and effectively disperses through both central and peripheral tumor regions

Cancer-specific promoter driven replication of oncolytic adenovirus (Ad) is cancer-specific, but shows low transcriptional activity. Thus, we generated several chimeric α-fetoprotein (AFP) promoter variants, containing reconstituted enhancer and silencer regions, to preferentially drive Ad replication in hepatocellular carcinoma (HCC). Modified AFP promoter, containing 2 enhancer A regions and a single enhancer B region (a2bm), showed strong and HCC-specific transcription. In AFP-positive HCCs, gene expression was 43- to 456-fold higher than those of control AFP promoter lacking enhancers. a2bm promoter was further modified by inserting multiple hypoxia-responsive elements (HRE) to generate Ha2bm promoter, which showed stronger transcriptional activity than a2bm promoter under hypoxic conditions. Ha2bm promoter-regulated oncolytic Ad (Ha2bm-d19) showed a stronger antitumor and proapoptotic effect than did a2bm promoter-regulated oncolytic Ad (a2bm-d19) in HCC xenograft tumors. Systemically administered Ha2bm-d19 caused no observable hepatotoxicity, whereas control replication-competent Ad, lacking cancer specificity (d19), induced significant hepatic damage. Ha2bm-d19 caused significantly lower expression of interleukin-6 than d19, showing that HCC-targeted delivery of Ad attenuates induction of the innate immune response against Ad. This chimeric AFP promoter enabled Ad to overcome the hypoxic tumor microenvironment and target HCC with high specificity, rendering it a promising candidate for the treatment of aggressive HCCs.

Deregulation of Frizzled Receptors in Hepatocellular Carcinoma.

G protein-coupled receptors (GPCRs) have a substantial role in tumorigenesis and are described as a “cancer driver”. Aberrant expression or activation of GPCRs leads to the deregulation of downstream signaling pathways, thereby promoting cancer progression. In hepatocellular carcinoma (HCC), the Wnt signaling pathway is frequently activated and it is associated with an aggressive HCC phenotype. Frizzled (FZD) receptors, a family member of GPCRs, are known to mediate Wnt signaling. Accumulating findings have revealed the deregulation of FZD receptors in HCC and their functional roles have been implicated in HCC progression. Given the important role of FZD receptors in HCC, we summarize here the expression pattern of FZD receptors in HCC and their corresponding functional roles during HCC progression. We also further review and highlight the potential targeting of FZD receptors as an alternative therapeutic strategy in HCC.

Induction of cancer cell stemness by depletion of macrohistone H2A1 in hepatocellular carcinoma.

Hepatocellular carcinomas (HCC) contain a subpopulation of cancer stem cells (CSCs), which exhibit stem cell-like features and are responsible for tumor relapse, metastasis, and chemoresistance. The development of effective treatments for HCC will depend on a molecular-level understanding of the specific pathways driving CSC emergence and stemness. MacroH2A1 is a variant of the histone H2A and an epigenetic regulator of stem-cell function, where it promotes differentiation and, conversely, acts as a barrier to somatic-cell reprogramming. Here, we focused on the role played by the histone variant macroH2A1 as a potential epigenetic factor promoting CSC differentiation. In human HCC sections we uncovered a significant correlation between low frequencies of macroH2A1 staining and advanced, aggressive HCC subtypes with poorly differentiated tumor phenotypes. Using HCC cell lines, we found that short hairpin RNA-mediated macroH2A1 knockdown induces acquisition of CSC-like features, including the growth of significantly larger and less differentiated tumors when injected into nude mice. MacroH2A1-depleted HCC cells also exhibited reduced proliferation, resistance to chemotherapeutic agents, and stem-like metabolic changes consistent with enhanced hypoxic responses and increased glycolysis. The loss of macroH2A1 increased expression of a panel of stemness-associated genes and drove hyperactivation of the nuclear factor kappa B p65 pathway. Blocking phosphorylation of nuclear factor kappa B p65 on Ser536 inhibited the emergence of CSC-like features in HCC cells knocked down for macroH2A1. Conclusion: The absence of histone variant macroH2A1 confers a CSC-like phenotype to HCC cells in vitro and in vivo that depends on Ser536 phosphorylation of nuclear factor kappa B p65; this pathway may hold valuable targets for the development of CSC-focused treatments for HCC. (Hepatology 2018;67:636-650).

Transcription factor AP-4 promotes tumorigenic capability and activates the Wnt/β-catenin pathway in hepatocellular carcinoma.

It has been reported that the transcription factor activating enhancer-binding protein 4 (TFAP4) is upregulated and associated with an aggressive phenotype in several cancers. However, the precise mechanisms underlying the oncogenic role of TFAP4 remain largely unknown.Methods: TFAP4 expression levels in hepatocellular carcinoma (HCC) cells and tissues were detected by quantitative real-time PCR (qPCR) and immunohistochemistry (IHC). In vitro and in vivo assays were performed to investigate the oncogenic function of TFAP4 in the tumor-initiating cell (TIC)-like phenotype and the tumorigenic capability of HCC cells. Luciferase reporter and chromatin immunoprecipitation (ChIP)-qPCR assays were performed to determine the underlying mechanism of TFAP4-mediated HCC aggressiveness.Results: TFAP4 was markedly upregulated in human HCC, and was associated with significantly poorer overall and relapse-free survival in patients with HCC. Furthermore, we found that overexpression of TFAP4 significantly enhanced, whereas silencing TFAP4 inhibited, the tumor sphere formation ability and proportion of side-population cells in HCC cells in vitro, and ectopic TFAP4 enhanced the tumorigenicity of HCC cells in vivo. Mechanistically, we demonstrated that TFAP4 played an important role in activating Wnt/β-catenin signaling by directly binding to the promoters of DVL1 (dishevelled segment polarity protein 1) and LEF1 (lymphoid enhancer binding factor 1).Conclusions: Our results provide new insight into the mechanisms underlying hyperactivation of the Wnt/β-catenin pathway in HCC, as well the oncogenic ability of TFAP4 to enhance the tumor-forming ability of HCC cells.

P19Arf inhibits aggressive progression of H-ras-driven hepatocellular carcinoma.

Arf, a well-established tumor suppressor, is either mutated or downregulated in a wide array of cancers. However, its role in hepatocellular carcinoma (HCC) progression is controversial. Conflicting observations have been published regarding its expression in HCC. In this study, we provide clear genetic evidence demonstrating a protective role of p19Arf in hepatocarcinogenesis. Using Ras-induced mouse model, we show that p19Arf deficiency accelerates progression of aggressive HCC in vivo. To investigate the role of p14ARF in human liver cancers, we analyzed its expression in human HCC using immunohistochemistry (IHC). We observe lack of nucleolar p14ARF in 43.02% of human HCC samples and that low expression of p14ARF strongly correlates with the early onset of HCC. Importantly, cirrhotic livers that did not progress to HCC harbor higher expression of the p14ARF protein in hepatocytes compared with that in cirrhotic livers with HCC. These results are significant because they suggest that nucleolar p14ARF can be used as early prognostic marker in chronic liver disease to reliably identify patients with high risk for developing liver cancer. Currently, there is no effective systemic therapy for advanced liver cancer; hence, more efficient patient screening and early detection of HCC would significantly contribute to the eradication of this devastating disease.

Characteristics of Hepatocellular Carcinoma Aggressiveness Factors in Turkish Patients

A large cohort of hepatocellular carcinoma (HCC) patients from several collaborating Turkish institutions were examined for the tumor parameters of maximum diameter (MTD), portal vein thrombosis (PVT), and α-fetoprotein (AFP) levels. A relationship was found between MTD and blood platelet levels. Patients with large ≥5 cm tumors who had normal platelet levels had significantly larger tumors, higher percent of PVT, and significantly lower blood total bilirubin and liver cirrhosis than similar ≥5 cm tumor patients having thrombocytopenia. A comparison of patients with and without PVT showed significantly larger tumors, greater multifocality, blood AFP, and C-reactive protein levels, and, interestingly, lower HDL levels in the patients with PVT. Fifty-eight percent of the total cohort had AFP levels ≤100 IU/mL (and 42.1% had values ≤20 IU/mL). These patients had significantly smaller tumors, less tumor multifocality and percent PVT, lower total bilirubin, and less cirrhosis. There was considerable geographic heterogeneity within Turkey in the patterns of HCC presentation, with areas of higher and lower hepatitis B virus, hepatitis D virus, cirrhosis, and tumor aggressiveness parameters. Turkish patients thus have distinct patterns of presentation, but the biological relationships between MTD and both platelets and bilirubin levels are similar to the relationships that have been reported in other ethnic patient groups.

MiR-520f promotes cell aggressiveness by regulating fibroblast growth factor 16 in hepatocellular carcinoma.

Cancer metastasis is a multistep cellular process, which has be confirmed one of mainly causes of cancer associated-death in hepatocellular carcinoma (HCC). MicroRNAs (miRNAs) participate in tumorigenesis function as either tumor suppressor genes or oncogenes. In order to elaborate the critical miRNAs and their targets in HCC, we compared the differential expression of miRNA between HCC tissues and normal tissues. Microarray analysis revealed there were several significantly up-expression miRNAs in HCC, compared to normal solid tissue. Among them, the expression of miR-520f was the most over-expression in HCC cell lines than that in human normal liver cells LO2, as well as up-regulated in HCC than that in the corresponding normal tissues. Moreover, Kaplan Meier-plotter analyses revealed that higher miR-520f levels were negatively correlated with poor overall survival. By applying bioinformatics methods to identify the targeting genes of miRNA, we demonstrated that fibroblast growth factor 16 (FGF16) was the miR-520f-targeted gene. Meanwhile, FGF16 exhibited similar expression patterns to miR-520f in HCC. Forced miR-520f expression accelerated HCC cells proliferation and aggressiveness in vitro and in vivo, whereas down-regulation of miR-520f caused an opposite outcome. Moreover, over-expression of FGF16 was closely related to the metastatic potential of HCC cells. Herein, we also confirmed that ectopic expression of FGF16 in HCC cells promoted proliferation, colony formation, and increased migration, invasion of HCC cells in vitro. Collectively, our results indicated that over-expression of miR-520f and FGF16 was positively associated with aggressive phenotypes and poor survival of patients with HCC, and miR-520f promoted HCC aggressive phenotypes by regulating the expression of FGF16. MiR-520f may be employed as a prognostic factor and therapeutic target for HCC.

Emerging Targets to Relieve Fat Stress-Induced Liver Diseases: UDCA, Tocotrienol, ω-3 PUFAs, and IgY Targeted NPC1L1 Cholesterol Transporter.

Fat stress-induced liver disease is a hepatic manifestation of metabolic syndrome initiated by excess fat accumulation and encompasses a wide spectrum of diseases from non-alcoholic fatty liver disease to nonalcoholic steatohepatitis, a precursor lesion progressing to more aggressive liver cirrhosis and hepatocellular carcinoma. Although the incidence of these fat stress-induced liver diseases is rapidly increasing worldwide in parallel with the growing epidemics of obesity and metabolic diseases, its exact pathogenesis is not well defined. Although obesity, sedentary life-style, altered dietary pattern, insulin resistance, altered intestinal barrier function, inflammatory cytokines, and oxidative stress have been acknowledged as contributing factors because of the indefinite pathogenesis of metabolic diseases, the only reliable treatment is lifestyle intervention composed of restrictive diet and exercise. Additionally, some existing medications such as pioglitazone and antioxidants such as vitamin E were reported to be effective; in this review, several novel agents especifically targeting nonalcoholic fatty liver disease pathogenesis under clinical trial will be introduced. These include an NPC1L1 blocker (ezetimibe), which significantly improved histological and symptomatic scores associated with steatohepatitis and fibrosis; clofibrate, phentoxyfylline, ursodeoxycholic acid, and tocopherol, all of which are prescribed to relieve fat stress; and additional IgY targeted NPC1L1, tocotrienol, ursodeoxycholic acid, and ω-3 polyunsaturated fatty acids, which are actively under investigation to confirm the safety of long-term use.

Liver Transplantation for High Risk Hepatocellular Carcinoma After Liver Resection: A Sequential or Salvage Approach?

BACKGROUND Liver transplantation (LT) is the best radical treatment of hepatocellular carcinoma (HCC). Salvage liver transplantation (SalvLT) provides good outcomes for recurrent HCC cases after initial curative liver resection (LR). However, the salvage strategy is not feasible in all situations due to aggressive recurrences. Recently, sequential liver transplantation (SeqLT) was proposed for cases that show adverse pathological features after LR, thus LT is performed pre-emptively before recurrence. In this report, we compared the outcomes of SalvLT and SeqLT for surgical treatment of HCC. MATERIAL AND METHODS One hundred and ten cases underwent LR for HCC, then were subjected to either SalvLT (n=91) or SeqLT (n=19), from January 2001 to December 2015. For cases that underwent several LR before LT, we collected the data of the last LR before transplantation. A comparison was made according to pre- and post-transplant clinical and pathological variables. Survival analysis and comparison between both pathways are provided. RESULTS The median interval (months) between LR and LT for the SeqLT group and the SalvLT group were 9.6 and 22.2, respectively. (p=0.01). The LR histopathological features were similar in both groups. In the SalvLT group, the histopathological comparison between the criteria of last LR and the criteria of liver explants revealed that 14 cases advanced from stage I to stage II, one cases from stage I to stage IIIa, one case from stage I to stage IIIb, one case from stage I to stage IIIc, three cases from stage II to stage IIIb and one case from stage II to stage IIIc. The overall rate of pathological upstaging in the SalvLT group was 27%. The incidence of post-transplant HCC recurrence was 5% (1/19) and 11% (10/91) for the SeqLT and SalvLT groups, respectively (p=0.4). The incidence of post-LT in-hospital mortality was 0% among the SeqLT group and 2% (2/91) among the SalvLT group. The estimated rates of five-year overall survival and cancer specific survival for the SeqLT group versus the SalvLT group were (92.3% versus 87.6%; p=0.4) and (92.3% versus 91.9%; p=0.7), respectively. CONCLUSIONS The SeqLT approach might be associated with low incidence of cancer recurrence, better overall survival, and less operative mortality. Another possible benefit is the avoidance of aggressive non-transplantable HCC recurrences. More studies and/or randomization are required for highre evidence conclusions.

Serum albumin levels in relation to tumor parameters in hepatocellular carcinoma patients.

Serum albumin levels have been shown to have prognostic significance in hepatocellular carcinoma (HCC), as part of an inflammatory index. The aim of this study was to examine the possible relationship of serum albumin levels to parameters of HCC aggressiveness. A large HCC patient cohort was retrospectively examined, and the possible relationships of albumin levels to tumor diameter, multifocality, portal vein thrombosis (PVT) and α-fetoprotein levels were examined. HCC patients with lower serum albumin levels had significantly larger maximum tumor diameters, greater prevalence of PVT, increased tumor multifocality and higher α-fetoprotein levels, than HCC patients with higher albumin levels. A correlation was found between levels of these tumor parameters and serum albumin levels. These results indicate that low serum albumin levels correlate with increased parameter measures of HCC aggressiveness, in addition to their role as a monitor of systemic inflammation. Decreased serum albumin might have a role in HCC aggressiveness.

Unusually Aggressive Hepatocellular Carcinoma Developing After Treatment of Hepatitis C With Direct-Acting Antivirals

Unusually Aggressive Hepatocellular Carcinoma Developing After Treatment of Hepatitis C With Direct-Acting Antivirals

Kindlin-2 promotes hepatocellular carcinoma invasion and metastasis by increasing Wnt/\u03b2-catenin signaling

BackgroundKindlin-2 is a member of the focal adhesion protein family that regulates invasion and metastasis in multiple malignancies; however, little is known about the role of Kindlin-2 in hepatocellular carcinoma (HCC) progression.MethodsImmunohistochemistry was used to investigate Kindlin-2 expression in 177 pairs of human HCC and adjacent liver tissue samples. The role of Kindlin-2 in the in vitro invasion and migration of HCC cell lines was evaluated in MHCC97H, LM3 and SMMC7721 cells. Microarray expression analysis was applied to explore the molecular mechanism through which Kindlin-2 promoted HCC progression. Quantitative real-time PCR and Western blotting were performed to verify the microarray results.ResultsHigh Kindlin-2 expression was found to significantly correlate with aggressive HCC clinicopathological features including tumor encapsulation, microvascular invasion, extrahepatic metastasis and poor prognosis. In vitro, Kindlin-2 knockout or knockdown inhibited HCC cell adhesion, migration and invasion, while ectopic Kindlin-2 expression promoted these processes. Importantly, Kindlin-2 activated Wnt/β-catenin signaling and increased β-catenin expression, especially levels of non-phosphorylated β-catenin, as well as two Wnt/β-catenin signaling pathway targets, Axin2 and MMP7. Kindlin-2 also induced a change in the expression profile of HCC cells, suggesting the cells underwent epithelial-mesenchymal transition. For example, the expression of the epithelial marker E-cadherin was downregulated, while the mesenchymal markers Vimentin, N-cadherin and Snail were upregulated.ConclusionKindlin-2 promotes HCC invasion, metastasis and epithelial-mesenchymal transition through Wnt/β-catenin signaling.

Downregulation of GPR155 as a prognostic factor after curative resection of hepatocellular carcinoma

BackgroundMolecular biomarkers capable of predicting recurrence patterns and prognosis are helpful for risk stratification and providing appropriate treatment to patients with hepatocellular carcinoma (HCC). In this study, we focused on G protein-coupled receptor 155 (GPR155), a cell surface signaling protein, as a candidate biomarker.MethodsWe analyzed GPR155 expression, DNA methylation, and copy number in HCC cell lines. The clinical significance of GPR155 expression was evaluated using 144 pairs of surgically resected liver and normal tissues with subgroup analysis based on hepatitis virus infection.ResultsGPR155 mRNA expression levels were differential and were decreased in 89% of HCC cell lines. No DNA methylation was detected, whereas copy number alterations were present in five (56%) HCC cell lines. GPR155 mRNA expression level was independent of background liver status and significantly lower in HCC tissues than corresponding normal liver tissues. The expression patterns of GPR155 protein by immunohistochemical staining were significantly associated with those of GPR155 mRNA. Downregulation of GPR155 was significantly associated with more aggressive HCC phenotypes including high preoperative α-fetoprotein, poor differentiation, serosal infiltration, vascular invasion, and advanced disease stage. Patients with downregulation of GPR155 were more likely to have worse prognosis after curative resection irrespective of hepatitis virus infection. Patients who experienced extrahepatic (distant) recurrences had significantly lower GPR155 expression than those with intrahepatic (liver confined) recurrences.ConclusionsDownregulation of GPR155 may serve as a prognosticator that also predicts initial recurrence sites independent of hepatitis virus infection.

Downregulation of miR‑136‑5p in hepatocellular carcinoma and its clinicopathological significance.

The clinical significance of microRNA (miR)-136-5p in hepatocellular carcinoma (HCC) has not been verified. Therefore, in the current study, the authors aimed to explore miR-136-5p expression and its clinical significance in HCC, as well as to investigate its potential target genes function. The authors detected the levels of miR-136-5p in 101 pairs of HCC and para-cancer tissues via reverse transcription-quantitative polymerase chain reaction. Gene Expression Omnibus database and the Cancer Genome Atlas (TCGA) database were used to further verify the clinical significance of miR-136-5p expression in HCC. The target genes prediction analysis of miR-136-5p, natural language processing (NLP) analysis of HCC in PubMed and gene functional enrichment analysis were conducted. The miR-136-5p level was markedly downregulated in HCC tissue, compared to para-non-tumor tissue. MiR-136-5p expression decreased in HCC patients with metastasis (P=0.004), advance TNM stage (P<0.001), portal vein tumor embolus (P=0.007) and vaso-invasion (P=0.003), compared with those HCC patients with non-metastasis, early TNM stage, non-portal vein tumor embolus and non-vaso-invasion, respectively. In the TCGA database, downregulated miR-136-5p was also observed in HCC tissue compared to normal liver tissue (P<0.001). There were 178 genes obtained from the overlap between predicted targets and NLP analysis. GO and KEGG pathway analyses revealed some significant pathways related to cancers. Downregulation of miR-136-5p may be responsible for the carcinogenesis and aggressiveness of HCC. miR-136-5p may act as an anti-carcinoma miRNA, which is essential for HCC progression through the regulation of various signaling pathways. Thus, miR-136-5p interaction may provide a novel strategy for HCC treatment.

RETRACTED ARTICLE: The lincRNA-ROR/miR-145 axis promotes invasion and metastasis in hepatocellular carcinoma via induction of epithelial-mesenchymal transition by targeting ZEB2

Emerging evidence show that long noncoding RNAs (lncRNAs) play critical roles in tumor development. LincRNA-ROR (linc-ROR) is known to promote tumor progress in several human cancers, including hepatocellular carcinoma (HCC). Nevertheless, the roles of linc-ROR in HCC metastasis and its underlying mechanisms remain fully unclear. In the present study, we showed that linc-ROR was upregulated in HCC tissues and high linc-ROR expression level predicted poor prognosis. Functionally, linc-ROR significantly induced epithelial-mesenchymal transition (EMT), and increased in vitro invasion and in vivo metastasis of HCC cells. Mechanistically, linc-ROR acted as a sponge for miR-145 to de-repress the expression of target gene ZEB2, thereby inducing EMT and promoting HCC metastasis. Collectively, our research indicates the potential of linc-ROR as a vital therapeutic target for the treatment of aggressive and metastatic HCC.

Abstract 1548: Down-regulation of 4-hydroxyphenylpyruvate dioxygenate (HPD) contributes to the pathogenesis of hepatocellular carcinoma (HCC) through ERK / BCL-2 signalling activation

Abstract Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies in the world. Metastasis, recurrence and therapy resistance remain major obstacles to the improvement of long-term survival and represent major causative factors contributing to the rising mortality rates and poor prognosis of HCC. Identification of key drivers important for clinical prognostic utility and elucidation of mechanisms involved in hepatocarcinogenesis is urgently needed to aid in the development of novel treatment modalities. To this end, we began our study with an analysis of a publicly gene expression dataset (GSE14520) comprising of transcriptomic profiles from a large cohort of human non-tumor liver and HCC clinical samples in hope to establish a prognostic gene signature associated with metastatic risk / recurrence status so to identify novel driver genes responsible for HCC development and progression. By this method, 4-hydroxyphenylpyruvate dioxygenase (HPD) was identified as a candidate tumor suppressor gene in HCC. HPD was found to be frequently down-regulated in primary HCC tumors as compared with peri-tumor liver tissues. Its expression negatively correlated with aggressive HCC pathological features, including tumor stage, metastasis, recurrence and survival. Notably, down-regulated HPD expression in HCC is in part a result of hypermethylation at the HPD promoter. The functional effect of HPD was then examined in HCC cells with or without HPD stably repressed or ectopically overexpressed. Upon knockdown of HPD, HCC cells displayed significantly enhanced abilities to form tumors, metastasize and confer sorafenib resistance in vitro and in vivo. Conversely, overexpression of HPD in HCC cells led to an opposing effect. Consistently, sorafenib-resistant HCC patient derived xenografts also displayed attenuated levels of HPD as compared with parental sorafenib-sensitive counterparts. Mechanistically, HPD down-regulation mediates aggressive cancer features in HCC through activation of an ERK and BCL-2 pro-survival signaling pathway, as evidenced by rescue experiments involving the ERK inhibitor U0126. Collectively, our findings suggest HPD down-regulation in HCC tumors to promote tumorigenicity, metastasis and sorafenib resistance through ERK / BCL-2 signaling activation and that HPD may represent a novel prognostic biomarker for HCC. Citation Format: Man Tong, Tin Lok Wong, Steve Tin-Chi Luk, Noélia Che, Kai Yau Wong, Tsun Ming Fung, Xin-Yuan Guan, Nikki P Lee, Yun-Fei Yuan, Terence K Lee, Stephanie Ma. Down-regulation of 4-hydroxyphenylpyruvate dioxygenate (HPD) contributes to the pathogenesis of hepatocellular carcinoma (HCC) through ERK / BCL-2 signalling activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1548. doi:10.1158/1538-7445.AM2017-1548

Abstract 4842: TP53INP1 negatively regulates ERK1/2 via p73-dependent DUSP10 expression to promote metastasis in hepatocellular carcinoma

Abstract The recurrence and metastasis of hepatocellular carcinoma (HCC) portends a poor prognosis and represents important clinical challenges. There is a great need to identify critical factors involved in HCC metastasis that will facilitate the development of new therapeutic strategies. We have previously found that the initiation, growth and self-renewal of CD133+ liver tumors to be fine-tuned by a balance of miR-130b overexpression and tumor protein 53 inducible nuclear protein 1 (TP53INP1) down-regulation, suggesting that TP53INP1 is a critical effector driving hepatocarcinogenesis. In this study, we aimed to further investigate the role of TP53INP1 in HCC metastasis. We showed TP53INP1 to be frequently down-regulated in advanced stage IV and metastatic human HCC tumors as compared with early stage (I-III) and primary tumors. Functional studies in immortalized normal liver cell line MIHA and HCC cell line MHCC-97L found TP53INP1 suppression in HCC to promote metastasis in vitro and in vivo. To elucidate the downstream signaling mechanism by which TP53INP1 regulates HCC metastasis, a Proteome Profiler Human Phospho-Kinase Array was utilized. Phospho-ERK was found to be consistently up-regulated in HCC cell lines with TP53INP1 knocked down, with its involvement in TP53INP1-mediated metastasis subsequently validated by rescue experiments using an ERK inhibitor U0126 or shERK1/2 knockdown approach. ERK1/2 is known to be negatively regulated by a family of dual-specificity MAPK phosphatase called DUSP/MKP. Screening of a panel of DUSP/MKP family members by qPCR identified DUSP10 to be commonly down-regulated in both MIHA and MHCC-97L cells with TP53INP1 suppressed as compared to controls. The importance of DUSP10 inactivation on ERK in TP53INP1-mediated HCC was substantiated by rescue experiments whereby DUSP10 ectopic expression in TP53INP1 suppressed cells reversed up-regulated phospho-ERK expression and enhanced HCC aggressiveness. Subsequent analysis of the DUSP10 promoter region by open-access database revealed four putative binding sites for p73, of which transcriptional activity has previously been found to be modulated by TP53INP1. Chromatin immunoprecipitation and luciferase reporter assays collectively demonstrated that TP53INP1 is vital for p73 transcriptional activity of DUSP10. Taken together, TP53INP1 down-regulation promotes HCC metastasis through a p73-dependent DUSP10/ERK signaling pathway. Note: This abstract was not presented at the meeting. Citation Format: Kai Yu Ng, Lok Hei Chan, Stella Chai, Man Tong, Xin Yuan Guan, Nikki P Lee, Yun Fei Yuan, Dan Xie, Terence K Lee, Alice Carrier, Nelson J Dusetti, Stephanie Ma. TP53INP1 negatively regulates ERK1/2 via p73-dependent DUSP10 expression to promote metastasis in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4842. doi:10.1158/1538-7445.AM2017-4842

Functional lipidomics: Palmitic acid impairs hepatocellular carcinoma development by modulating membrane fluidity and glucose metabolism

These data collectively demonstrate the biomedical potential of using altered lipid metabolism as a diagnostic marker for cancerous cells and open an opportunity for treating aggressive HCCs by targeting altered C16:0 metabolism. (Hepatology 2017;66:432-448).

Oncogenic Role of SND1 in Development and Progression of Hepatocellular Carcinoma.

SND1, a subunit of the miRNA regulatory complex RISC, has been implicated as an oncogene in hepatocellular carcinoma (HCC). In this study, we show that hepatocyte-specific SND1 transgenic mice (Alb/SND1 mice) develop spontaneous HCC with partial penetrance and exhibit more highly aggressive HCC induced by chemical carcinogenesis. Livers from Alb/SND1 mice exhibited a relative increase in inflammatory markers and spheroid-generating tumor-initiating cells (TIC). Mechanistic investigations defined roles for Akt and NF-κB signaling pathways in promoting TIC formation in Alb/SND1 mice. In human xenograft models of subcutaneous or orthotopic HCC, administration of the selective SND1 inhibitor 3', 5'-deoxythymidine bisphosphate (pdTp), inhibited tumor formation without effects on body weight or liver function. Our work establishes an oncogenic role for SND1 in promoting TIC formation and highlights pdTp as a highly selective SND1 inhibitor as a candidate therapeutic lead to treat advanced HCC. Cancer Res; 77(12); 3306-16. ©2017 AACR.