Regulation Of Hepatocellular Carcinoma Research Articles

Roles of M6A Regulators in Hepatocellular Carcinoma: Promotion or Suppression.

Hepatocellular carcinoma (HCC) is the sixth globally diagnosed cancer with a poor prognosis. Although the pathological factors of hepatocellular carcinoma are well elucidated, the underlying molecular mechanisms remain unclear. N6-methyladenosine (M6A) is adenosine methylation occurring at the N6 site, which is the most prevalent modification of eukaryotic mRNA. Recent studies have shown that M6A can regulate gene expression, thus modulating the processes of cell self-renewal, differentiation, and apoptosis. The methyls in M6A are installed by methyltransferases ("writers"), removed by demethylases ("erasers") and recognized by M6A-binding proteins ("readers"). In this review, we discuss the roles of the above regulators in the progression and prognosis of HCC, and summarize the clinical association between M6A modification and hepatocellular carcinoma, so as to provide more valuable information for clinical treatment.

Contributions and Prognostic Values of N6-Methyladenosine RNA Methylation Regulators in Hepatocellular Carcinoma.

IntroductionThe methylation at position N6 of adenine is called N6-methyladenosine (m6A). This transcriptional RNA modification exerts a very active and important role in RNA metabolism and in other biological processes. However, the activities of m6A associated with malignant liver hepatocellular carcinoma (LIHC) are unknown and are worthy of study.Materials and MethodsUsing the data of University of California, Santa Cruz (UCSC), the expression of M6A methylation regulators in pan-cancer was evaluated as a screening approach to identify the association of M6A gene expression and 18 cancer types, with a specific focus on LIHC. LIHC datasets of The Cancer Genome Atlas (TCGA) were used to explore the expression of M6A methylation regulators and their clinical significance. Gene Ontology (GO) analysis and Gene Set Enrichment Analysis (GSEA) were used to explore the underlying mechanism based on the evaluation of aberrant expression of m6A methylation regulators.ResultsThe expression alterations of m6A-related genes varied across cancer types. In LIHC, we found that in univariate Cox regression analysis, up-regulated m6A modification regulators were associated with worse prognosis, except for ZC3H13. Kaplan–Meier survival curve analysis indicated that higher expression of methyltransferase-like protein 3 (METTL3) and YTH N6-methyladenosine RNA binding protein 1 (YTHDF1) genes related to the worse survival rate defined by disease-related survival (DSS), overall survival (OS), progression-free interval (PFI), and disease-free interval (DFI). Up-regulated m6A methylation regulator group (cluster2) obtained by consensus clustering was associated with poor prognosis. A six-gene prognostic signature established using the least absolute shrinkage and selection operator (LASSO) Cox regression algorithm performed better in the early (I + II; T1 + T2) stages than in the late (III + IV; T3 + T4) stages of LIHC. Using the gene signature, we constructed a risk score and found that it was an independent predictive factor for prognosis. Using GSEA, we identified processes involved in DNA damage repair and several biological processes associated with malignant tumors that were closely related to the high-risk group.ConclusionIn summary, our study identified several genes associated with m6A in LIHC, especially METTL3 and YTHDF1, and confirmed that a risk signature comprised of m6A-related genes was able to forecast prognosis.

DLG1-AS1 is activated by MYC and drives the proliferation and migration of hepatocellular carcinoma cells through miR-497-5p/SSRP1 axis

BackgroundLong non-coding RNAs (lncRNAs) have been reported to be biological regulators in hepatocellular carcinoma (HCC). DLG1 antisense RNA 1 (DLG1-AS1) has been found to be up-regulated in cervical cancer. However, its function and underlying mechanism in HCC remains unknown.MethodsDLG1-AS1 expression was assessed in HCC cells and normal cell by RT-qPCR. Luciferase reporter assay, RNA pull down assay and RIP assay were used to demonstrate the interaction between DLG1-AS1 and miR-497-5p.ResultsDLG1-AS1 was highly expressed in HCC cells. Silencing of DLG1-AS1 led to the inhibition of HCC cell growth and migration. Besides, MYC induced the transcriptional activation of DLG1-AS1. MYC could facilitate HCC cellular processes by up-regulating DLG1-AS1. MiR-497-5p could interact with DLG1-AS1 in HCC cells. Down-regulation of miR-497-5p could reverse the impacts of DLG1-AS1 silencing on HCC cells. SSRP1 expression could be positively regulated by DLG1-AS1 but was negatively regulated by miR-497-5p. Knockdown of DLG1-AS1 suppressed tumor growth in nude mice.ConclusionsDLG1-AS1 is activated by MYC and functions as an oncogene in HCC via miR-497-5p/SSRP1 axis.

Transcriptional and epigenetic landscape of Ca2+-signaling genes in hepatocellular carcinoma.

Calcium (Ca2+) signaling has a major role in regulating a wide range of cellular mechanisms, including gene expression, proliferation, metabolism, cell death, muscle contraction, among others. Recent evidence suggests that ~ 1600 genes are related to the Ca2+ signaling. Some of these genes' expression is altered in several pathological conditions, including different cancer types, and epigenetic mechanisms are involved. However, their expression and regulation in hepatocellular carcinoma (HCC) and the liver are barely known. Here, we aimed to explore the expression of genes involved in the Ca2+-signaling in HCC, liver regeneration, and hepatocyte differentiation, and whether their expression is regulated by epigenetic mechanisms such as DNA methylation and histone posttranslational modifications (HPM). Results show that several Ca2+-signaling genes' expression is altered in HCC samples; among these, a subset of twenty-two correlate with patients' survival. DNA methylation correlates with eight of these genes' expression, and Guadecitabine, a hypomethylating agent, regulates the expression of seven down-regulated and three up-regulated genes in HepG2 cells. The down-regulated genes displayed a marked decrease of euchromatin histone marks, whereas up-regulated genes displayed gain in these marks. Additionally, the expression of these genes is modulated during liver regeneration and showed similar profiles between in vitro differentiated hepatocytes and liver-derived hepatocytes. In conclusion, some components of the Ca2+-signaling are altered in HCC and displayed a correlation with patients' survival. DNA methylation and HMP are an attractive target for future investigations to regulate their expression. Ca2+-signaling could be an important regulator of cell proliferation and differentiation in the liver.

N6-methyladenosine (m6A)-mediated messenger RNA signatures and the tumor immune microenvironment can predict the prognosis of hepatocellular carcinoma.

BackgroundN6-methyladenosine (m6A)-mediated ribonucleic acid (RNA) methylation is considered to be the most significant and abundant epigenetic modification in eukaryotic cells, and plays an essential role in the carcinogenesis and molecular pathogenesis of hepatocellular carcinoma (HCC). However, the relationship between m6A regulation and immune cell infiltration of the tumor immune microenvironment (TIME) has not yet been clarified. We aimed to investigate the roles of m6A RNA gene regulators in HCC immune regulation and prognosis.MethodsThe Cancer Genome Atlas (TCGA) database was used, and unsupervised clustering of 21 m6A regulators was performed based on differential gene expression. Gene Set Variation Analysis (GSVA), single-sample Gene Set Enrichment Analysis (ssGSEA), the empirical Bayes method, and m6A scores were used in our analyses.ResultsOf 433 samples, 101 (23.22%) had m6A regulatory factor mutations. From these, we identified three m6A subtypes, which correlated with different TIME phenotypes: immune rejection, immune infiltration, and immune deficiency. Tumors with low methyltransferase-like 3 (METTL3) expression had increased infiltration of dendritic cells (DCs) in the TIME. Reduced METTL3 expression also led to an overall increase in expression of major histocompatibility complex (MHC) molecules, costimulatory molecules, and adhesion molecules. The m6A subtypes were scored and analyzed for correlations. Patients with epithelial-mesenchymal transition (EMT) subtypes had lower m6A scores than the other three molecular subtypes. Survival analysis found that patients with low m6A scores had better overall survival [hazard ratio (HR) 1.6 (1.1–2.3)] and a 1.16 times better 5-year survival rate than patients with high m6A scores (56% vs. 48%).ConclusionsOur results demonstrated that three different m6A modification subtypes contribute to immune regulation in HCC and have potential as novel prognostic indicators and immune therapeutic targets.

Integration Analysis of m6A Regulators and m6A-Related Genes in Hepatocellular Carcinoma

Abstract Background: N6-Methyladenosine (m6A) RNA methylation of eukaryotic mRNA is involved in the progression of various tumors. We aimed to investigate m6A-related genes and m6A regulators in hepatocellular carcinoma (HCC) and their association with prognosis in HCC. Methods: We downloaded liver cancer sample data from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium database. A total of 21 m6A regulators and 1258 m6A-related genes were then analyzed by consensus clustering, Spearman’s correlation, GO, KEGG, LASSO Cox regression, and univariate Cox regression analyses. Finally, we constructed a risk prognostic model. Results: We obtained 192 candidate m6A-related genes and 3 m6A regulators, including YTHDF1, YTHDF2, and YTHDC1. The expression of these genes and regulators differed significantly in different stages of HCC. Based on Cox regression analysis, 19 of 98 m6A-related prognostic genes were obtained to construct a risk score model. The 1- and 3-year area under the curves (AUCs) among HCC patients were greater than 0.7. Finally, based on analysis of mutation differences between high- and low-risk score groups, we determined that TP53 had the highest mutation frequency in the high-risk HCC patient group, whereas titin (TTN) had the highest mutation frequency in the low-risk HCC patient group. Conclusion: This study comprehensively analyzed m6A regulators and m6A-related genes through an integrated bioinformatic analysis, including expression, clustering, protein–protein interaction, and prognosis, thus providing novel insights into the roles of m6A regulators and m6A-related genes in HCC.

The Aberrant Long Non-Coding RNA NEAT1 Affected Nrf2/HO-1 in the Regulation of Hepatocellular Carcinoma

The Aberrant Long Non-Coding RNA NEAT1 Affected Nrf2/HO-1 in the Regulation of Hepatocellular Carcinoma

The EGFR-P38 MAPK axis up-regulates PD-L1 through miR-675-5p and down-regulates HLA-ABC via hexokinase-2 in hepatocellular carcinoma cells.

BackgroundImmunotherapy has been shown to be a promising strategy against human cancers. A better understanding of the immune regulation in hepatocellular carcinoma (HCC) could help the development of immunotherapy against HCC. The epidermal growth factor receptor (EGFR) signaling is frequently activated in HCC and plays important roles in tumorigenesis. However, its role in HCC immunity is still largely unknown. This study aimed to investigate the impact of EGFR signaling on programmed death‐ligand 1 (PD‐L1) and human leukocyte antigen class‐I (HLA‐I) expression in HCC cells and its underlying mechanisms.MethodsThe expression of phosphorylated EGFR (p‐EGFR), PD‐L1, and HLA‐I (HLA‐ABC) in HCC specimens was detected by immunohistochemistry, and their correlations were analyzed. PD‐L1 and HLA‐ABC expression in EGFR‐activated HCC cells were detected by quantitative real‐time PCR, Western blotting, and flow cytometry, and T cell‐mediated lysis was performed to test the immunosuppressive effects of PD‐L1 and HLA‐ABC alterations in HCC cells. Furthermore, the underlying mechanisms of EGFR activation‐induced PD‐L1 up‐regulation and HLA‐ABC down‐regulation were explored by animal experiments, luciferase reporter assay, and gene gain‐ and loss‐of‐function studies.Resultsp‐EGFR was positively correlated with PD‐L1 and negatively correlated with HLA‐ABC expression in HCCs. EGFR activation by its ligand EGF up‐regulated PD‐L1 and down‐regulated HLA‐ABC in HCC cells, which was functionally important and could be abolished by the EGFR inhibitor, gefitinib, both in vitro and in vivo. Mechanistically, enhanced P38 mitogen‐activated protein kinase (MAPK) activation down‐regulated microRNA‐675‐5p (miR‐675‐5p) and up‐regulated glycolysis‐related enzyme hexokinase 2 (HK2); miR‐675‐5p down‐regulation enhanced the stability of PD‐L1 mRNA probably via the 3’‐untranslated region (3’‐UTR) of PD‐L1 and thereby caused PD‐L1 accumulation, and HK2 up‐regulation enhanced aerobic glycolysis and mediated a decrease in HLA‐ABC.ConclusionsThe EGFR‐P38 MAPK axis could up‐regulate PD‐L1 through miR‐675‐5p and down‐regulate HLA‐ABC via HK2 in HCC cells. Our study reveals a novel signaling network that may cause immune suppression in HCC and suggests that EGFR signaling can be targeted for HCC immunotherapy.

Research advances in Kupffer cells participating in the regulation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common type of primary liver cancer with high mortality worldwide. Among the common malignant tumors in China, HCC ranks fourth in terms of incidence rate and ranks second in terms of mortality, which seriously threatens the health and life safety of the Chinese people. This article mainly introduces the dual role of Kupffer cells (KCs) in HCC and briefly describes its interaction with liver parenchymal cells and nonparenchymal cells and related targeted treatment methods. The analysis shows that in-depth research on KCs in the regulation of HCC helps to provide new ideas for further treatment of HCC.

Astrocyte elevated gene-1 (AEG-1): A key driver of hepatocellular carcinoma (HCC).

An array of human cancers, including hepatocellular carcinoma (HCC), overexpress the oncogene Astrocyte elevated gene-1 (AEG-1). It is now firmly established that AEG-1 is a key driver of carcinogenesis, and enhanced expression of AEG-1 is a marker of poor prognosis in cancer patients. In-depth studies have revealed that AEG-1 positively regulates different hallmarks of HCC progression including growth and proliferation, angiogenesis, invasion, migration, metastasis and resistance to therapeutic intervention. By interacting with a plethora of proteins as well as mRNAs, AEG-1 regulates gene expression at transcriptional, post-transcriptional, and translational levels, and modulates numerous pro-tumorigenic and tumor-suppressive signal transduction pathways. Even though extensive research over the last two decades using various in vitro and in vivo models has established the pivotal role of AEG-1 in HCC, effective targeting of AEG-1 as a therapeutic intervention for HCC is yet to be achieved in the clinic. Targeted delivery of AEG-1 small interfering ribonucleic acid (siRNA) has demonstrated desired therapeutic effects in mouse models of HCC. Peptidomimetic inhibitors based on protein-protein interaction studies has also been developed recently. Continuous unraveling of novel mechanisms in the regulation of HCC by AEG-1 will generate valuable knowledge facilitating development of specific AEG-1 inhibitory strategies. The present review describes the current status of AEG-1 in HCC gleaned from patient-focused and bench-top studies as well as transgenic and knockout mouse models. We also address the challenges that need to be overcome and discuss future perspectives on this exciting molecule to transform it from bench to bedside.

The Role of Histone Acetylation-/Methylation-Mediated Apoptotic Gene Regulation in Hepatocellular Carcinoma.

Epigenetics, an inheritable phenomenon, which influences the expression of gene without altering the DNA sequence, offers a new perspective on the pathogenesis of hepatocellular carcinoma (HCC). Nonalcoholic steatohepatitis (NASH) is projected to account for a significant share of HCC incidence due to the growing prevalence of various metabolic disorders. One of the major molecular mechanisms involved in epigenetic regulation, post-translational histone modification seems to coordinate various aspects of NASH which will further progress to HCC. Mounting evidence suggests that the orchestrated events of cellular and nuclear changes during apoptosis can be regulated by histone modifications. This review focuses on the current advances in the study of acetylation-/methylation-mediated histone modification in apoptosis and the implication of these epigenetic regulations in HCC. The reversibility of epigenetic alterations and the agents that can target these alterations offers novel therapeutic approaches and strategies for drug development. Further molecular mechanistic studies are required to enhance information governing these epigenetic modulators, which will facilitate the design of more effective diagnosis and treatment options.

Revealing Epigenetic Factors of circRNA Expression by Machine Learning in Various Cellular Contexts.

SummaryCircular RNAs (circRNAs) have been identified as naturally occurring RNAs that are highly represented in the eukaryotic transcriptome. Although a large number of circRNAs have been reported, the underlying regulatory mechanism of circRNAs biogenesis remains largely unknown. Here, we integrated in-depth multi-omics data including epigenome, transcriptome, and non-coding RNA and identified candidate circRNAs in six cellular contexts. Next, circRNAs were divided into two classes (high versus low) with different expression levels. Machine learning models were constructed that predicted circRNA expression levels based on 11 different histone modifications and host gene expression. We found that the models achieve great accuracy in predicting high versus low expressed circRNAs. Furthermore, the expression levels of host genes of circRNAs, H3k36me3, H3k79me2, and H4k20me1 contributed greatly to the classification models in six cellular contexts. In summary, all these results suggest that epigenetic modifications, particularly histone modifications, can effectively predict expression levels of circRNAs.

Long Noncoding RNA PRR34-AS1 Aggravates the Progression of Hepatocellular Carcinoma by Adsorbing microRNA-498 and Thereby Upregulating FOXO3.

PurposeLong noncoding RNAs are differentially expressed in hepatocellular carcinoma (HCC) and have been validated as essential regulators in HCC. However, there is limited knowledge regarding the detailed roles and mechanisms of most lncRNAs in HCC cells. In this study, the expression profiles of PRR34 antisense RNA 1 (PRR34-AS1) in HCC tissues and cell lines were determined. In addition, the detailed roles and underlying mechanisms of PRR34-AS1 in HCC cells were comprehensively elucidated.MethodsReverse transcription-quantitative polymerase chain reaction (PCR) was performed to measure PRR34-AS1 expression in HCC cells. Cell proliferation, apoptosis, and migration and invasion were evaluated in vitro using the cell counting kit-8 (CCK-8) assay, flow cytometric analysis, and transwell cell migration and invasion assays, respectively. In vivo tumor growth was determined using tumor xenograft experiments. The potential miRNA targets of PRR34-AS1 were predicted via bioinformatic analysis and further confirmed using the luciferase reporter assay, RNA immunoprecipitation assay, and reverse transcription-quantitative PCR.ResultsPRR34-AS1 was highly expressed in HCC tissues and cell lines, and its interference suppressed HCC cell proliferation, migration, and invasion but promoted cell apoptosis in vitro. In addition, loss of PRR34-AS1 decreased tumor growth in HCC cells in vivo. Mechanistically, PRR34-AS1 functions as a miR-498 sponge and subsequently increases forkhead box O3 (FOXO3) expression in HCC cells. Rescue experiments revealed that the suppressive effects triggered by PRR34-AS1 knockdown on the malignant characteristics of HCC cells could be abrogated by inhibiting miR-498 or restoring FOXO3 expression.ConclusionThe depletion of PRR34-AS1 suppresses the oncogenicity of HCC cells by targeting the miR-498/FOXO3 axis. Therefore, the PRR34-AS1/miR-498/FOXO3 pathway may offer a basis for HCC treatment.

LncRNA DDX11-AS1 accelerates hepatocellular carcinoma progression via the miR-195-5p/MACC1 pathway

Introduction and aimLong non-coding RNA (lncRNA) has been shown to be a vital regulator of cancer progression, including hepatocellular carcinoma (HCC). However, the role of DEAD/H box protein 11 antisense RNA 1 (DDX11-AS1) in HCC remains to be further studied. Material and MethodsThe expression levels of DDX11-AS1, miR-195-5p and metastasis-associated in colon cancer-1 (MACC1) were determined by quantitative real-time PCR (qRT-PCR). Cell counting kit-8 (CCK-8), transwell and apoptosis determination assays were used to evaluate cell proliferation, migration, invasion and apoptosis, respectively. Mice xenograft models were constructed to verify the effect of DDX11-AS1 on HCC tumor growth in vivo. Furthermore, lactate production, glucose consumption, ATP level and glucose uptake were detected to assess cell glucose metabolism. The interactions among DDX11-AS1, miR-195-5p and MACC1 were verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Moreover, western blot (WB) analysis was performed to evaluate the protein levels. ResultsDDX11-AS1 was upregulated in HCC tissues and cells, and its silencing could inhibit HCC cell proliferation, migration, invasion and glucose metabolism, and promote apoptosis in vitro. Also, DDX11-AS1 knockdown reduced HCC tumor growth in vivo. Besides, DDX11-AS1 could interact with miR-195-5p, and miR-195-5p inhibitor reversed the inhibitory effect of silenced DDX11-AS1 on HCC cell progression. In addition, MACC1 was a target of miR-195-5p, and its overexpression reversed the suppression effect of miR-195-5p on HCC cell progression. ConclusionOur data revealed that DDX11-AS1 could act as an oncogenic regulator in HCC, providing a potential therapeutic target for HCC treatment.

Development and validation of a m6A-related gene signature for predicting the prognosis of hepatocellular carcinoma.

Background: This study aimed to investigate the prognostic role of m6A methylation regulators in hepatocellular carcinoma (HCC). Materials & methods: Gene expression matrices were downloaded from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium, and Gene Expression Omnibusdatabases. Univariate and multivariate regression analysis wereutilized to determine the m6A risk genes. Results: Two m6A-related risk genes (YTHDF1, YTHDF2) were identified in the TCGA HCC cohort. The m6A-correlated risk score is an independent risk factor for the overall survival of the TCGA HCC cohort. Finally, we verified the reliability of our results using three external datasets. Conclusion: The m6A-correlated gene signature has prognostic value in HCC patients and thus provides guidance for the treatment of HCC.

Overexpression of anillin is related to poor prognosis in patients with hepatocellular carcinoma

BackgroundAnillin (ANLN) is required for tumor growth. It has been proven that knockdown of ANLN effectively reduces the occurrence of hepatocellular carcinoma (HCC) in transgenic mice. However, the functional role of ANLN in HCC patients remains to be elucidated. MethodsBoth microarray and TCGA project were used for the analyses of ANLN expression and regulation in HCC. The effect of ANLN on proliferation and cell cycle was detected by CCK-8, colony formation assay and flow cytometry. ANLN expression was measured by immunohistochemistry. Correlation between ANLN expression and clinicopathological features was assessed by Pearson Chi-square test and 5-year overall survival after liver resection was evaluated by Kaplan–Meier method. ResultsIncreased copy number, decreased methylation levels in the CpG island and upregulated histone hypermethylation of ANLN were found in HCC. Knockdown of ANLN inhibited proliferation and induced G2/M phase arrest in SMMC-7721 cells. ANLN was mainly expressed in the nucleus and showed significantly higher expression levels in cancerous tissues than those in paired adjacent tissues. Moreover, nuclear ANLN expression levels in HCC metastases were significantly higher than those in primary HCC. The results of Cox proportional hazards regression model suggested that ANLN nuclear expression in HCC was an independent risk factor for poor 5-year overall survival of patients after liver resection. ConclusionsANLN is a potential therapeutic target for HCC. Patients with nuclear ANLN overexpression in HCC tissue may need adjuvant therapy after liver resection.

N6-Methyladenosine RNA Methylation Regulators Have Clinical Prognostic Values in Hepatocellular Carcinoma.

Although it is widely accepted that N6-methyladenosine (m6A) RNA methylation plays critical roles in tumorigenesis and progression, the values of m6A modification are less known in hepatocellular carcinoma. The major purpose of our current studies is to investigate the role of m6A regulators in hepatocellular carcinoma and whether it can affect the prognosis of hepatocellular carcinoma. Here we demonstrate that most of the m6A regulators are highly expressed in hepatocellular carcinoma. Furthermore, we cluster hepatocellular carcinoma into two subgroups (cluster 1/2) by applying consensus clustering to m6A regulators. Compared with the cluster 1 subgroup, the cluster 2 subgroup was significantly associated with a higher pathological grade and survival. Based on these findings, we reveal a risk signature by using three m6A regulators, which are not only an independent prognostic marker but also a predictor of the clinicopathological features in hepatocellular carcinoma. In conclusion, m6A regulators are crucial participants in the malignant progression of hepatocellular carcinoma and are potential targets for prognosis.

MicroRNA-342-3p is a potent tumour suppressor in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a cancer with multiple aetiologies and widespread prevalence. Largely refractory to current treatments, HCC is the fourth leading cause of cancer-related deaths worldwide. MicroRNAs (miRNAs) are important regulators in HCCs. We aimed to identify tumour suppressor miRNAs during tumour regression in a conditional c-MYC-driven mouse model (LT2/MYC) of HCC, and to evaluate their therapeutic potential for HCC treatment. We performed miRNA expression profiling of developed and regressing LT2/MYC tumours and in-depth invitro gain- and loss-of-function analyses. The effect of adeno-associated virus (AAV) vector-mediated miR-342-3p treatment was evaluated in 3 HCC mouse models. We identified miR-342-3p as a tumour suppressor miRNA in HCC, with increased expression in regressing tumours. Forced miR-342-3p expression in hepatoma cells showed significantly decreased cell proliferation, migration, and colony formation. Invivo administration of AAV-miR-342-3p led to significant attenuation of tumour development and increased overall survival. We identified monocarboxylic acid transporter 1 (MCT1) as a bona fide target of miR-342-3p in HCC. We show that the tumour suppressor role of miR-342-3p is executed partly by modulating the lactate transport function of MCT1. Importantly, we find miR-342-3p downregulated in tumours from patients with HCC compared with matched non-tumour tissues, inversely correlating with MCT1 expression. We observed similar findings in TCGA-LIHC data. In our study, we identified and validated miR-342-3p as a tumour suppressor miRNA in HCC. We demonstrated its therapeutic efficacy in significantly attenuating tumour development, and prolonging survival, in different HCC mouse models. Identification of miR-342-3p as an effective tumour suppressor opens a therapeutic avenue for miRNA-mediated attenuation of HCC development. Hepatocellular carcinoma (HCC), the most common type of liver cancer, affects diverse populations and has a global impact, being the fourth leading cause of cancer deaths worldwide. There are currently no systemic therapies for HCC that can significantly prolong long-term survival. Thus, novel effective treatment options are urgently required. To understand the molecular basis of tumour regression, we compared tumours and regressing liver tumours in mice. We show that a small non-coding miRNA, miR-342-3p, is a tumour suppressor in HCC. Expression of miR-342-3p is low in tumours and high in regressing tumours. When miR-342-3p is delivered to mouse livers with HCC, it cansignificantly slow down liver tumour development and improve survival. Our study highlights the promising therapeutic potential of miR-342-3p intervention in HCC.

Prognostic Value of an m6A RNA Methylation Regulator-Based Signature in Patients with Hepatocellular Carcinoma.

Purposes Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. Recent researches have demonstrated that m6A methylation regulators play a key role in various cancers, such as gastric cancer and colon adenocarcinoma. Several m6A methylation regulators are reported to predict the prognosis of HCC. Therefore, there is a need to further identify the predictive value of m6A methylation regulators in HCC. Methods We utilized The Cancer Genome Atlas (TCGA) database to obtain the gene expression profile of m6A RNA methylation regulators and clinical information for patients with HCC. Besides, we identified two clusters of HCC with various clinical factors by consensus clustering analysis. Then the least absolute shrinkage and selection operator (LASSO) and the Cox regression analysis were applied to construct a prognostic signature. Results Except for ZC3H13 and METTL14, a majority of the thirteen m6A RNA methylation regulators were significantly overexpressed in HCC specimens. HCC patients were classified into two groups (cluster 1 and cluster 2). The cluster 1 was with a significantly worse prognosis than cluster 2, and most of the 13 known m6A RNA methylation regulators were upregulated in cluster 1. Besides, we developed a prognostic signature consisting of YTHDF2, YTHDF1, METTL3, KIAA1429, and ZC3H13, which could successfully differentiate high-risk patients. More importantly, univariate and multivariate Cox regression analysis indicated that the signature-based risk score was an independent prognostic factor for patients with HCC. Conclusions Our study showed these five m6A RNA methylation regulators can be used as practical and reliable prognostic tools of HCC, which might have potential value for therapeutic strategies.

Immunosuppressive receptor LILRB1 acts as a potential regulator in hepatocellular carcinoma by integrating with SHP1.

Immunosuppressive receptor LILRB1 regulates tumors progression by transducing immune inhibitory signals via intracellular immunoreceptor tyrosine-based inhibitory motifs. However, its role in Hepatocellular Carcinoma (HCC) remains vague. This study is aimed to disclose the association between LILRB1 and HCC. Immunoblotting and qRT-PCR were employed to evaluate the level of LILRB1 in hepatocarcinoma cells. LILRB1-positive cells in tissue array were measured using immunohistochemistry staining. The relation among LILRB1, SHP1 and SHP2 and survival rates were analyzed using Gene Expression Profiling Interactive Analysis (GEPIA) and Oncomine database. LILRB1 was robustly reduced in hepatocarcinoma cells compared to normal cells. Clinically, LILRB1 was significantly higher in 49 of 75 (65%) paired paracarcinoma tissues than that in paired HCC samples. 48 of 75 (64%) HCC subjects in tissue microarray showed low level of LILRB1, compared to 25 of 75 (33%) in paired-adjacent tissues. Oncomine database and GEPIA analysis confirmed that LILRB1 was lower in HCC than normal tissues. Additionally, lowLILRB1 had a significant association with clinicopathological characteristics and Disease Free Survival, but no association with Overall Survival in HCC patients. Mechanismly, positive correlation between LILRB1 and SHP1, but not SHP2 was observed in HCC. LILRB1 possibly plays an antitumor effect in hepatocarcinoma cells by integrating SHP1, providing evidence that LILRB1 might be involved in the pathologic progression of HCC.