Regulation Of Hepatocellular Carcinoma Research Articles

Identification and validation of ferroptosis-related prognostic risk model and immune landscape in hepatocellular carcinoma

BackgroundFerroptosis has been paid much more attention on account of the correlation withtumorigenesis and development. However, the molecular characteristics and immune landscape of ferroptosis regulators in hepatocellular carcinoma (HCC) have not been fully elucidated. MethodsRNA-sequencing data and matched clinical data were collected from The Cancer Genome Atlas (TCGA) database, then underwent gene expression, genetic variations, prognostic risk model, and immune characterization analyses. An independent cohort from Gene Expression Omnibus (GEO) database was utilized to validate ferroptosis-related prognostic risk model. ResultsWe first identified the differentially expressed ferroptosis regulators between the tumor tissues and normal controls in HCC. Furthermore, the prognostic risk model based on ferroptosis regulators was constructed, of which the high risk group presented poor clinical outcomes compared to the low risk group. Importantly, the ferroptosis-related prognostic risk model consistently presented excellent prediction ability in recognizing the high and low risk patients according to the validation from an independent cohort. Subsequently, immune landscape analysis uncovered that most of ferroptosis regulatory genes were significantly associated with the infiltration of multiple immune cells and the expression of immune checkpoints in HCC. Moreover, the correlations of risk score with immune cells infiltration and immune checkpoints were determined in HCC. ConclusionOur study developed a prognostic risk model based on ferroptosis regulatory genes, which could accurately predict the patients’ prognosis. Immune characteristics analysisrevealed that ferroptosis regulatory genes were associated with immune cells infiltration and immune checkpoints in HCC.

N6-methyladenosine with immune infiltration and PD-L1 in hepatocellular carcinoma: novel perspective to personalized diagnosis and treatment.

Increasing evidence elucidated N6-methyladenosine (m6A) dysregulation participated in regulating RNA maturation, stability, and translation. This study aimed to demystify the crosstalk between m6A regulators and the immune microenvironment, providing a potential therapeutic target for patients with hepatocellular carcinoma (HCC). Totals of 371 HCC and 50 normal patients were included in this study. GSE121248 and GSE40367 datasets were used to validate the expression of HNRNPC. The R package "ConsensusClusterPlus" was performed to screen consensus clustering types based on the expression of m6A regulators in HCC. The R package "pheatmap", "immunedeconv", "survival", "survminer" and "RMS" were applied to investigate the expression, immunity, overall survival, and clinical application in different clusters and expression groups. Comprehensive analysis of HNRNPC in pan-cancer was conducted by TIMER2 database. Besides, HNRNPC mRNA and protein expression were verified by qRT-PCR and immunohistochemistry analysis. Most of m6A regulators were over-expressed excerpt for ZC3H13 in HCC. Three independent clusters were screened based on m6A regulators expression, and the cluster 2 had a favorable prognosis in HCC. Then, the cluster 2 was positively expression in macrophage, hematopoietic stem cell, endothelial cell, and stroma score, while negatively in T cell CD4+ memory and mast cell. We identified HNRNPC was an independent prognostic factor in HCC, and nomogram performed superior application value for clinical decision making. Moreover, PD-L1 was significantly up-regulated in HCC tissues, cluster 1, and cluster 3, and we found PD-L1 expression was positively correlated with HNRNPC. Patients with HCC in high-expression groups was associated with tumor-promoting cells. Besides, HNRNPC was correlated with prognosis, TMB, and immune checkpoints in cancers. Particularly, the experiments confirmed that HNRNPC was positively expression in HCC cells and tissues. The m6A regulators play irreplaceable roles in prognosis and immune infiltration in HCC, and the relationship of HNRNPC and PD-L1 possesses a promising direction for therapeutic targets of immunotherapy response. Exploration of m6A regulators pattern could be build the prognostic stratification of individual patients and move toward to personalized treatment.

Crosstalk between myeloid and B cells shapes the distinct microenvironments of primary and secondary liver cancer.

The tumor microenvironment is distinctive in primary and secondary liver cancer. B cells represent an important component of immune infiltrates. Here, we demonstrated that B cells are an important regulator in hepatocellular carcinoma (HCC) and colorectal cancer liver metastasis (CRLM) microenvironments. B cells displayed distinct developmental trajectories in HCC and CRLM. Single-cell analysis revealed that IgG+ plasma cells preferentially accumulated in HCC while IgA+ plasma cells were preferentially enriched in CRLM. Mechanistically, IgG+ plasma cells in HCC were recruited by tumor-associated macrophages via the CXCR3-CXCL10 axis, whereas IgA+ plasma cells in CRLM were recruited by metastatic tumor cells via CCR10-CCL28 signaling. Functionally, IgG+ plasma cells preferentially promoted pro-tumorigenic macrophages formation in HCC, and IgA+ plasma cells preferentially induced granulocytic myeloid-derived suppressor cells activation in CRLM. Clinically, increased infiltration of IgG+ plasma cells and macrophages in HCC was correlated to worse survival, while increased intratumoral IgA+ plasma cells and neutrophils in CRLM indicated poor prognosis. Taken together, this study demonstrated plasma and myeloid cell-mediated immunosuppression in HCC and CRLM, suggesting that selectively modulating primary or secondary tumor-related immunosuppressive regulatory networks might reprogram the microenvironment and provide an immunotherapeutic strategy for treating liver cancer.

TMEM147 Correlates with Immune Infiltration and Serve as a Potential Prognostic Biomarker in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies and is associated with high mortality. Transmembrane protein 147 (TMEM147) is a seven-transmembrane protein that may mediate immune regulation. However, the relevance of TMEM147 to immune regulation in HCC and the prognosis of HCC patients are unclear. We analyzed TMEM147 expression in HCC by using the Wilcoxon rank-sum test. Real time quantitative PCR (RT-qPCR) and Western blot analysis of tumor tissues and cell lines were used to verify TMEM147 expression in HCC. The influence of TMEM147 on HCC prognosis was assessed using Kaplan-Meier analysis, Cox regression analysis, and a prognostic nomogram. The functions of the TMEM147-related differentially expressed genes (DEGs) were identified by Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses and gene set enrichment analysis (GSEA). In addition, we examined the associations between TMEM147 expression and immune infiltration using single-sample gene set enrichment analysis (ssGSEA) and immunofluorescence staining of HCC tissues. Our results showed that the expression of TMEM147 was significantly higher in human HCC tissues than in adjacent normal liver tissues, with similar findings in human HCC cell lines. High TMEM147 expression was correlated with T stage, pathological stage, histological grade, race, alpha-fetoprotein level, and vascular invasion in HCC. Moreover, we revealed that high TMEM147 expression was associated with shorter survival times and that TMEM147 could be a risk factor for overall survival, along with T stage, M stage, pathological stage, and tumor status. Mechanistic studies revealed that high TMEM147 expression was linked to the B lymphocyte, antigen response, IL6 signaling pathway, cell cycle, Kirsten rat sarcoma viral oncogene homolog (KRAS) signaling pathway, and myelocytomatosis oncogene (MYC) targets. Correspondingly, TMEM147 expression was positively associated with the infiltration of immune cells, including Th2 cells, follicular helper T cells, macrophages, and NK CD56 bright cells in HCC. TMEM147 might be a biomarker for poor prognosis and is related to immune cell infiltration in HCC.

Expression and prognostic value of DNA sensors in hepatocellular carcinoma.

DNA sensor proteins play an important role in transducing DNA signals to induce immune responses that initiate inflammation or clear pathogens. It has been previously shown that several DNA sensors are involved in regulating tumor biology and/or cancer immunology. However, a systemic analysis of DNA sensor expression and its correlation with prognosis has not been conducted. Here, we analyzed messenger RNA expression and protein abundance in liver cancer databases and found that the genes of 5 DNA sensors (POLR3A, PRKDC, DHX9, cGAS, and MRE11) were consistently upregulated in tumor tissue. Moreover, the expression of these DNA sensor genes correlated with patient survival. Using a gene alterations analysis, we discovered that patients with genetically altered DNA sensors had significantly lower survival compared with an unaltered group. Furthermore, receiver-operating characteristic curves confirmed that the signatures of the 5 DNA sensors were independent prognostic factors in hepatocellular carcinoma. Tumor-infiltrating immune cell analysis revealed that expression of all 5 DNA sensors correlated with the amount of B cells, CD8 T cells, CD4 T cells, Tregs, DCs, Mϕs, and neutrophils. Surprisingly, 4 of the DNA sensors (POLR3A, PRKDC, DHX9, and MRE11) were inversely correlated with the amount of γδ T cells. Gene set enrichment analysis showed that all 5 DNA sensor genes were enriched for oxidative phosphorylation and xenobiotic metabolism. These results suggest that expression of these DNA sensors is associated with a unique immune profile and metabolic regulation in hepatocellular carcinoma.

INKA2-AS1 Is a Potential Promising Prognostic-Related Biomarker and Correlated with Immune Infiltrates in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a malignancy with one of the worst prognoses. Long noncoding RNAs (lncRNAs) may be important in cancer development and may serve as new biomarkers for the diagnosis and treatment of various tumors, according to mounting research. The purpose of this study was to investigate the expression of INKA2-AS1 and clinical importance in HCC patients. The TCGA database was used to obtain the human tumor samples, while the TCGA and GTEx databases were used to gather the human normal samples. We screened differentially expressed genes (DEGs) between HCC and nontumor tissues. Investigations were made into the statistical significance and clinical significance of INKA2-AS1 expression. A single-sample gene set enrichment analysis (ssGSEA) was used to examine potential relationships between immune cell infiltration and INKA2-AS1 expression. In this investigation, we found that HCC specimens had considerably greater levels of INKA2-AS1 expression than nontumor specimens. When utilizing the TCGA datasets and the GTEx database, high INKA2-AS1 expression showed an AUC value for HCC of 0.817 (95% confidence interval: 0.779 to 0.855). Pan-cancer assays revealed that numerous tumor types had dysregulated levels of INKA2-AS1. Gender, histologic grade, and pathologic stage were all substantially correlated with high INKA2-AS1 expression. A survival study indicated that HCC patients with high INKA2-AS1 expression have shorter OS, DSS, and PFI than those with low INKA2-AS1 expression. Multivariate analysis indicated that INKA2-AS1 expression was an independent prognostic factor for OS of patients with HCC. According to immune analysis, the expression of INKA2-AS1 was favorably correlated with T helper cells, Th2 cells, macrophages, TFH, and NK CD56bright cells and negatively correlated with Th17 cells, pDC, cytotoxic cells, DC, Treg, Tgd, and Tcm. The results of this study collectively suggest that INKA2-AS1 has the potential to be a novel biomarker for predicting the prognosis of HCC patients as well as a significant immune response regulator in HCC.

Circ_RBM23 knockdown suppresses chemoresistance, proliferation, migration and invasion of sorafenib-resistant HCC cells through miR-338-3p/RAB1B axis.

Circular RNA RNA-binding motif protein 23 (circ_RBM23; ID: hsa_circ_0000524) is a novel regulator in hepatocellular carcinoma (HCC). Herein, we planned to investigate its role in sorafenib resistance in HCC. Levels of circ_RBM23, microRNA (miR)-338-3p, Ras-related GTPase-trafficking protein (RAB1B), Snail and E-cadherin were detected by real-time quantitative PCR and western blotting. Sorafenib resistant (SR) HCC cells (Huh7/SR and SK-HEP-1/SR) were established by acquisition of sorafenib resistance, and cell functions were measured by MTT assay, Edu assay, colony formation assay, apoptosis assay, transwell assay, and in vivo xenograft formation assay. Crosslink between miR-338-3p and circ_RBM23 or RAB1B was confirmed by bioinformatics analysis and dual-luciferase reporter assay. Circ_RBM23 upregulation was discovered in the tissues of SR patients and SR cells, which was accompanied with miR-338-3p downregulation and RAB1B upregulation. The 50% inhibitory concentration (IC50) of sorafenib in SR cells was greatly suppressed by interfering circ_RBM23 or reinforcing miR-338-3p, allied with this was the inhibition of EdU-positive cell rate, colony formation and migration/invasion abilities under sorafenib treatment, as well as the enhancement of apoptotic rate. Moreover, circ_RBM23 inhibition delayed tumor growth of Huh7/SR cells under sorfanib treatment in vivo. Circ_RBM23 promoted chemoresistance, malignant proliferation, migration and invasion of SR HCC cells by modulating miR-338-3p/RAB1B axis.

Role of ferroptosis and its non-coding RNA regulation in hepatocellular carcinoma.

Ferroptosis is a newly discovered form of programmed cell death that involves the accumulation of iron-dependent lipid peroxides and plays a vital role in the tumorigenesis, development, and drug resistance of various tumors such as hepatocellular carcinoma (HCC). As a hotspot in molecular biology, non-coding RNAs (ncRNAs) participate in the initiation and progression of HCC, either act as oncogenes or tumor suppressors. Recent studies have shown that ncRNAs can regulate ferroptosis in HCC cells, which would affect the tumor progression and drug resistance. Therefore, clarifying the underlying role of ferroptosis and the regulatory role of ncRNA on ferroptosis in HCC could develop new treatment interventions for this disease. This review briefly summarizes the role of ferroptosis and ferroptosis-related ncRNAs in HCC tumorigenesis, progression, treatment, drug resistance and prognosis, for the development of potential therapeutic strategies and prognostic markers in HCC patients.

Upregulation of TUBG1 expression promotes hepatocellular carcinoma development.

Tubulin γ-1 (TUBG1) is a highly conserved component of the centrosome and its deregulation is involved in the development of several types of cancer. However, the role of TUBG1 in hepatocellular carcinoma (HCC) remains unclear. In this study, we found that TUBG1 was upregulated in human HCC cells and tissues and that TUBG1 upregulation was associated with promoter hypomethylation in HCC tissues. TUBG1 knockdown suppressed the proliferation, invasion, and migration of HCC cells. While TUBG1 expression was positively correlated with CD4 + memory T lymphocyte infiltration, it was negatively correlated with CD4 + regulatory T-cell infiltration in human HCC tissues. Furthermore, TUBG1 expression was positively correlated with the expression of genes involved in cell division. Noticeably, high expression of TUBG1 was associated with poor prognosis in patients with HCC. Overall, our findings revealed that TUBG1 promotes hepatocarcinogenesis by increasing proliferation, invasion, and migration of HCC cells and may regulate T lymphocyte infiltration. The current findings provide important insights into TUBG1 regulation in HCC, which could provide new therapeutic targets for hepatocarcinoma which has a very high incidence and mortality rate worldwide.

A novel polypeptide encoded by the circular RNA ZKSCAN1 suppresses HCC via degradation of mTOR

Backgroundhsa_circ_0001727 (circZKSCAN1) has been reported to be a tumor-associated circRNA by sponging microRNAs. Intriguingly, we found that circZKSCAN1 encoded a secretory peptide (circZKSaa) in the liver. The present study aims to elucidate the potential role and molecular mechanism of circZKSaa in the regulation of hepatocellular carcinoma (HCC) progression.MethodsThe circRNA profiling datasets (RNA-seq data GSE143233 and GSE140202) were reanalyzed and circZKSCAN1 was selected for further study. Mass spectrometry, polysome fractionation assay, dual-luciferase reporter, and a series of experiments showed that circZKSCAN1 encodes circZKSaa. Cell proliferation, apoptosis, and tumorigenesis in nude mice were examined to investigate the functions of circZKSaa. Mechanistically, the relationship between the circZKSaa and mTOR in HCC was verified by immunoprecipitation analyses, mass spectrometry, and immunofluorescence staining analyses.ResultsReceiver operating characteristic (ROC) analysis demonstrated that the secretory peptide circZKSaa encoded by circZKSCAN1 might be the potential biomarker for HCC tissues. Through a series of experiments, we found that circZKSaa inhibited HCC progression and sensitize HCC cells to sorafenib. Mechanistically, we found that the sponge function of circZKSCAN1 to microRNA is weak in HCC, while overexpression of circZKSaa promoted the interaction of FBXW7 with the mammalian target of rapamycin (mTOR) to promote the ubiquitination of mTOR, thereby inhibiting the PI3K/AKT/mTOR pathway. Furthermore, we found that the high expression of cicZKSCAN1 in sorafenib-treated HCC cells was regulated by QKI-5.ConclusionsThese results reveal that a novel circZKSCAN1-encoded peptide acts as a tumor suppressor on PI3K/AKT/mTOR pathway, and sensitizes HCC cells to sorafenib via ubiquitination of mTOR. These findings demonstrated that circZKSaa has the potential to serve as a therapeutic target and biomarker for HCC treatment.

Crosstalk between 5-methylcytosine and N6-methyladenosine machinery defines disease progression, therapeutic response and pharmacogenomic landscape in hepatocellular carcinoma

BackgroundAccumulated evidence highlights the significance of the crosstalk between epigenetic and epitranscriptomic mechanisms, notably 5-methylcytosine (5mC) and N6-methyladenosine (m6A). Herein, we conducted a widespread analysis regarding the crosstalk between 5mC and m6A regulators in hepatocellular carcinoma (HCC).MethodsPan-cancer genomic analysis of the crosstalk between 5mC and m6A regulators was presented at transcriptomic, genomic, epigenetic, and other multi-omics levels. Hub 5mC and m6A regulators were summarized to define an epigenetic and epitranscriptomic module eigengene (EME), which reflected both the pre- and post-transcriptional modifications.Results5mC and m6A regulators interacted with one another at the multi-omic levels across pan-cancer, including HCC. The EME scoring system enabled to greatly optimize risk stratification and accurately predict HCC patients’ clinical outcomes and progression. Additionally, the EME accurately predicted the responses to mainstream therapies (TACE and sorafenib) and immunotherapy as well as hyper-progression. In vitro, 5mC and m6A regulators cooperatively weakened apoptosis and facilitated proliferation, DNA damage repair, G2/M arrest, migration, invasion and epithelial-to-mesenchymal transition (EMT) in HCC cells. The EME scoring system was remarkably linked to potential extrinsic and intrinsic immune escape mechanisms, and the high EME might contribute to a reduced copy number gain/loss frequency. Finally, we determined potential therapeutic compounds and druggable targets (TUBB1 and P2RY4) for HCC patients with high EME.ConclusionsOur findings suggest that HCC may result from a unique synergistic combination of 5mC-epigenetic mechanism mixed with m6A-epitranscriptomic mechanism, and their crosstalk defines therapeutic response and pharmacogenomic landscape.

PFKFB3-mediated Pro-glycolytic Shift in Hepatocellular Carcinoma Proliferation.

Metabolic reprogramming, in particular, glycolytic regulation, supports abnormal survival and growth of hepatocellular carcinoma (HCC) and could serve as a therapeutic target. In this study, we sought to identify glycolytic regulators in HCC that could be inhibited to prevent tumor progression and could also be monitored invivo, with the goal of providing a theragnostic alternative to existing therapies. An orthotopic HCC rat model was used. Tumors were stimulated into a high-proliferation state by use of off-target liver ablation and were compared with lower-proliferating controls. We measured invivo metabolic alteration in tumors before and after stimulation, and between stimulated tumors and control tumors using hyperpolarized 13C magnetic resonance imaging (MRI) (h13C MRI). We compared metabolic alterations detected by h13C MRI to metabolite levels from exvivo mass spectrometry, mRNA levels of key glycolytic regulators, and histopathology. Glycolytic lactate flux increased within HCC tumors 3 days after tumor stimulation, correlating positively with tumor proliferation as measured with Ki67. This was associated with a shift towards aerobic glycolysis and downregulation of the pentose phosphate pathway detected by mass spectrometry. MRI-measured lactate flux was most closely coupled with PFKFB3 expression and was suppressed with direct inhibition using PFK15. Inhibition of PFKFB3 prevents glycolytic-mediated HCC proliferation, trackable by invivo h13C MRI.

ACE2 negatively regulates the Warburg effect and suppresses hepatocellular carcinoma progression via reducing ROS-HIF1α activity.

Aerobic glycolysis has pleiotropic roles in the pathogenesis of hepatocellular carcinoma (HCC). Emerging studies revealed key promoters of aerobic glycolysis, however, little is known about its negative regulators in HCC. In this study, an integrative analysis identifies a repertoire of differentially expressed genes (DNASE1L3, SLC22A1, ACE2, CES3, CCL14, GYS2, ADH4, and CFHR3) that are inversely associated with the glycolytic phenotype in HCC. ACE2, a member of the rennin-angiotensin system, is revealed to be downregulated in HCC and predicts a poor prognosis. ACE2 overexpression significantly inhibits the glycolytic flux as evidenced by reduced glucose uptake, lactate release, extracellular acidification rate, and the expression of glycolytic genes. Opposite results are noticed in loss-of-function studies. Mechanistically, ACE2 metabolizes Ang II to Ang-(1-7), which activates Mas receptor and leads to the phosphorylation of Src homology 2-containing inositol phosphatase 2 (SHP-2). SHP2 activation further blocks reactive oxygen species (ROS)-HIF1α signaling. Addition of Ang-(1-7) or the antioxidant N-acetylcysteine compromises in vivo additive tumor growth and aerobic glycolysis induced by ACE2 knockdown. Moreover, growth advantages afforded by ACE2 knockdown are largely glycolysis-dependent. In clinical settings, a close link between ACE2 expression and HIF1α or the phosphorated level of SHP2 is found. Overexpression of ACE2 significantly retards tumor growth in patient-derived xenograft model. Collectively, our findings suggest that ACE2 is a negative glycolytic regulator, and targeting the ACE2/Ang-(1-7)/Mas receptor/ROS/HIF1α axis may be a promising therapeutic strategy for HCC treatment.

Development and experimental verification of a prognosis model for cuproptosis-related subtypes in HCC.

Cuproptosis is a recently discovered mechanism of programmed cell death caused by intracellular aggregation of mitochondrial lipoylated proteins and destabilization of iron-sulfur proteins triggered by copper. Hepatocellular carcinoma (HCC) is a common malignant tumor with a poor prognosis. We aimed to predict the survival of patients with HCC using the cuproptosis-related gene (CRG) expression. We analyzed the expression, methylation, and mutation status of CRGs in 538 HCC patients and correlated the date with clinical prognosis. HCC patients were divided into two clusters based on their CRG expression. The relationship between CRGs, risk genes, and the immune microenvironment was analyzed using the CIBERSORT algorithm and the single-cell data analysis method. A cuproptosis risk model was constructed according to the five risk genes using the LASSO COX method. To facilitate the clinical applicability of the proposed risk model, we constructed a nomogram and conducted an antineoplastic drug sensitivity analysis. Our results suggest that the expression levels of CRGs in HCC are regulated by methylation. The prognoses were significantly different between the patients of the two clusters. The prognostic risk score positively correlated with memory T cell activation and negatively correlated with natural killer (NK) and regulatory T cell activation. Our findings indicate the involvement of CRG regulation in HCC and provide new insights into prognosis assessment. Drug sensitivity analysis predicted drug candidates for the treatment of patients with different HCC subtypes.

Diagnostic and prognostic value of m5C regulatory genes in hepatocellular carcinoma.

Background: A high mortality rate makes hepatocellular carcinoma (HCC) one of the most common types of cancer globally. 5-methylcytosine (m5C) is an epigenetic modification that contributes to the prognosis of several cancers, but its relevance to HCC remains unknown. We sought to determine if the m5C-related regulators had any diagnostic or prognostic value in HCC. Methods: M5C regulatory genes were screened and compared between HCC and normal tissue from The Cancer Genome Atlas (TCGA)and Gene Expression Omnibus (GEO) databases. Least absolute shrinkage and selection operator method (LASSO) and univariate Cox regression analysis of differentially expressed genes were then performed to identify diagnostic markers. A LASSO prognostic model was constructed using M5C regulatory genes with prognostic values screened by TCGA expression data. HCC patients were stratified based on risk score, then clinical characteristics analysis and immune correlation analysis were performed for each subgroup, and the molecular functions of different subgroups were analyzed using both Gene Set Enrichment Analysis (GSEA) and Gene Set Variation Analysis (GSVA). The prognostic model was evaluated using univariate and multivariate Cox analyses as well as a nomogram. Molecular typing was performed according to m5C regulatory genes and immune checkpoint genes expression respectively, and clinical characterization and immune correlation analysis were performed for each subgroup. Results: M5C regulatory genes are expressed differently in HCC patients with different clinical and pathological characteristics, and mutations in these genes are frequent. Based on five m5C regulators (NOP2, NSUN2, TET1, YBX1, and DNMT3B), we constructed a prognostic model with high predictive ability. The risk score was found to be an independent prognostic indicator. Additionally, risk scores can also be applied in subgroups with different clinical characteristics as prognostic indicators. Conclusion: The study combined data from TCGA and GEO for the first time to reveal the genetic and prognostic significance of m5C-related regulators in HCC, which provides new directions for identifying predictive biomarkers and developing molecularly targeted therapies for HCC.

Characterization of chromatin regulators in hepatocellular carcinoma to guide clinical therapy.

Background: Hepatocellular carcinoma (HCC) is notorious for its high mortality and incidence. Accumulating evidence confirms that chromatin regulators (CRs) have a significant impact on cancer. Therefore, exploring the mode of action and prognostic value of CRs is imminent for the treatment of hepatocellular carcinoma. Method: Transcriptome and clinical data for this study have been downloaded from TCGA (https://portal.gdc.cancer.gov/) and ICGC (https://dcc.icgc.org/). Univariate analysis was used to screen CRs with prognostic value, and our prognostic risk score signature was developed using least absolute shrinkage along with selection operator (lasso) Cox regression analysis. The CRs-based prognostic model was constructed in the TCGA dataset, and low-risk HCC patients had a better prognosis, which was finally validated in the ICGC dataset. We used the receiver operating characteristic curve to identify the accuracy of the prediction model and establish a line chart to prove the clinical effectiveness of the model. We also discussed the differences in drug sensitivity via CellMiner database, tumor immune microenvironment via ssGSEA algorithm, and clinical characteristics among different risk groups. Results: A prognostic model consisting of seven CRs was constructed and verified in HCC patients. Furthermore, we found that this risk score prognostic signature could independently predict the prognosis of HCC patients. Functional enrichment analysis revealed that CRs are mainly associated with cancer-related signaling pathways and metabolic pathways. In addition, immune cell abundance correlates with risk score levels Conclusion: In brief, we systematically explored the mode of action of CRs in HCC patients and established a reliable prognostic prediction model.

Impact of nitric oxide in liver cancer microenvironment

The pro- or antitumoral properties of nitric oxide (NO) are dependent on local concentration, redox state, cellular status, duration of exposure and compartmentalization of NO generation. The intricate network of the tumor microenvironment (TME) is constituted by tumor cells, stromal and immune cells surrounded by active components of extracellular matrix that influence the biological behavior and, consequently, the treatment and prognosis of cancer. The review describes critical events in the crosstalk of cellular and stromal components in the TME, with special emphasis in the impact of NO generation in the regulation of hepatocellular carcinoma (HCC). The increased expression of nitric oxide synthase (NOS) in tumors and NO-end products in plasma have been associated with poor prognosis of cancer. We have assessed the level of the different isoforms of NOS in tumors and its relation to cell proliferation and death markers, and cell death receptor expression in tumors, and apoptotic markers and ligands of TNF-α receptor family in blood from a cohort of patients with HCC from different etiologies submitted to orthotopic liver transplantation (OLT). The high levels of NOS2 in tumors were associated with low plasma concentration of apoptotic markers (M30 and M65), FasL and TNF-α in HCV patients. By contrast, the low levels of NOS2 in tumors from alcohol-derived patients was associated with increased Trail-R1 expression in tumors, and circulating Trail levels compared to observed in plasma from HCV- and alcohol + HCV-derived patients. This study reinforces the association between increased NOS2 expression and potential risk of low patients’ survival in HCC. However, a differential functional relevance of NOS expression in HCC seems to be influenced by etiologies.

Molecular subtypes, prognostic and immunotherapeutic relevant gene signatures mediated by DNA methylation regulators in hepatocellular carcinoma.

Growing evidence has revealed the crucial role of epigenetics in tumor progression and immune response. However, the molecular subtypes and their microenvironment characterization mediated by DNA methylation regulators in hepatocellular carcinoma remain little known. In this study, we comprehensively integrated the transcriptome profiling of twenty DNA methylation regulators in hepatocellular carcinoma. Consensus clustering was used to identify distinct methylation regulator-related molecular subtypes. The prognostic DMS signature was constructed using principal components analysis. Most regulators experienced a low genomic variation, but we found a remarkably difference in mRNA expression of these regulators between normal and tumor tissues. Three distinct methylation regulator-related molecular subtypes were successfully identified according to the expression of 20 regulators, which had substantially different biological characteristics and prognosis. The classic carcinogenic pathways and stromal activity including TGF-beta, p53 and WNT signaling pathway were significantly activated in subtype B, leading to a survival inferiority in subtype B compared to other two subtypes. Further analysis demonstrated the constructed DMS signature was an independent predictive biomarker in patient prognosis. Two anti-checkpoint immunotherapy cohorts demonstrated patients with high DMS presented significantly improved treatment advantages and enhanced responses especially the survival prolonged. Generally, the high DMS groups improved more than 15% clinical response to immunotherapy than low DMS groups. In conclusion, this study identified three DNA methylation regulator-related subtypes with distinct clinical, molecular and biological characteristics, and constructed a prognostic and immunotherapeutic relevant gene signature. It might help to promote individualized immunotherapy for hepatocellular carcinoma from the perspective DNA methylation regulators.

Long non-coding RNA X-inactive specific transcript suppresses the progression of hepatocellular carcinoma through microRNA-221-3p-targeted regulation of O6-methylguanine-DNA methyltransferase

ABSTRACT MicroRNA-221-3p (miR-221-3p) is an important regulator involved in the progression and prognosis of various cancers. In this study, we aimed to investigate the diagnostic and prognostic value of miR-221-3p expression along with long non-coding RNA X–inactive specific transcript (XIST), which was identified as its upstream regulator in hepatocellular carcinoma (HCC) by bioinformatics analysis, and further validated by RNA immunoprecipitation (RIP) and dual-luciferase reporter assays. Their expression was measured in tumor tissues and corresponding non-tumor tissues by quantitative real-time PCR (qRT-PCR), which revealed that XIST was weakly expressed in HCC cells and tumors, while miR-221-3p was overexpressed. Complete knockdown of XIST enhanced HCC cell proliferation and migration and inhibited apoptosis, as observed by MTT, transwell, and flow cytometry experiments, respectively. Animal studies validated that XIST knockdown induces tumor growth in vivo. In contrast, upregulation of XIST in HCC cells suppressed their proliferation and migration, stimulated apoptosis, and retarded the growth rate of tumors in vivo. These effects were partially reversed by upregulating miR-221-3p expression. Furthermore, we demonstrated that O6-methylguanine-DNA methyltransferase (MGMT) is a downstream target of miR-221-3p. It was weakly expressed in HCC cells and tumors and showed a negative correlation with miR-221-3p. Forced MGMT expression repressed proliferation and migration and enhanced apoptosis in HCC cells. Nevertheless, these anti-tumor effects induced by MGMT overexpression could be abolished by miR-221-3p upregulation. Collectively, our findings reveal that XIST blocks the development of HCC through miR-221-3p-targeted regulation of MGMT. This reveals a new mechanism involved in the development of HCC.

Targeting anillin inhibits tumorigenesis and tumor growth in hepatocellular carcinoma via impairing cytokinesis fidelity.

Targeting cytokinesis can suppress tumor growth by blocking cell division and promoting apoptosis. We aimed to characterize key cytokinesis regulator in hepatocellular carcinoma (HCC) progression, providing insights into identifying promising HCC therapeutic targets. The unbiased bioinformatic screening identified Anillin actin binding protein (ANLN) as a critical cytokinesis regulator involved in HCC development. Functional assay demonstrated that knockdown of ANLN inhibited HCC growth by inducing cytokinesis failure and DNA damage, leading to multinucleation and mitotic catastrophe. Mechanistically, ANLN acts as a scaffold to strengthen interaction between RACGAP1 and PLK1. ANLN promotes PLK1-mediated RACGAP1 phosphorylation and RhoA activation to ensure cytokinesis fidelity. To explore the function of ANLN in HCC tumorigenesis, we hydrodynamically transfected c-Myc and NRAS plasmids into Anln+/+, Anln+/-, and Anln-/- mice through tail vein injection. Hepatic Anln ablation significantly impaired c-Myc/NRAS-driven hepatocarcinogenesis. Moreover, enhanced hepatic polyploidization was observed in Anln ablation mice, manifesting as increasing proportion of cellular and nuclear polyploidy. Clinically, ANLN is upregulated in human HCC tissues and high level of ANLN is correlated with poor patients' prognosis. Additionally, the proportion of cellular polyploidy decreases during HCC progression and ANLN level is significantly correlated with cellular polyploidy proportion in human HCC samples. In conclusion, ANLN is identified as a key cytokinesis regulator contributing to HCC initiation and progression. Our findings revealed a novel mechanism of ANLN in the regulation of cytokinesis to promote HCC tumorigenesis and growth, suggesting targeting ANLN to inhibit cytokinesis may be a promising therapeutic strategy for HCC.