Role of epithelial to mesenchymal transition in hepatocellular carcinoma

The impact of liver fibrosis on the progression of hepatocellular carcinoma via a hypoxia-immune-integrated prognostic model

The impact of liver fibrosis on the deterioration of hepatocellular carcinoma (HCC) remains controversial. We hope to explore this issue through establishing a fibrosis-hypoxia-glycolysis-immune related prognostic model. Liver fibrosis-related genes from Molecular Signatures Database were used to evaluate the degree of fibrosis in HCC patients from the TCGA database. The patients were divided into two groups using the fibrosis-related expression matrix based on the algorithm uniform manifold approximation and projection (UMAP) and evaluated for fibrosis by UMAP cluster and gene enrichment analysis. Prognostic model was constructed by differential analysis, LASSO, and multivariate regression analysis. Immune-infiltration analysis was performed by CIBERSORT. Quantitative PCR and immunohistochemistry were performed to measure the gene expression levels in HCC patients from our hospital. In 365 HCC patients from the TCGA database, 111 HCC patients with high fibrosis score have a worse prognosis than those with low fibrosis based on 129 genes related to liver fibrosis, which may be caused by the interaction between fibrosis, angiogenesis, hypoxia, glycolysis, inflammatory response, and high immune infiltration. We constructed a Fibrosis-Hypoxia-Glycolysis-Immune Prognostic Model (FHGISig), which could significantly predict disease progression in HCC patients. Furthermore, we revealed a close correlation between FHGISig and immune cell infiltration level as well as immune checkpoints. Finally, PCR results found TFF3 mRNA was significantly lower in cirrhotic HCC patients compared with non-cirrhotic ones. Liver fibrosis is a poor-prognostic factor for HCC, and our FHGISig could significantly predict disease progression, which could also be a potential predictive marker for immunotherapy in HCC patients.

Application Value of Antimicrobial Peptides in Gastrointestinal Tumors

Gastrointestinal cancer is a common clinical malignant tumor disease that seriously endangers human health and lacks effective treatment methods. As part of the innate immune defense of many organisms, antimicrobial peptides not only have broad-spectrum antibacterial activity but also can specifically kill tumor cells. The positive charge of antimicrobial peptides under neutral conditions determines their high selectivity to tumor cells. In addition, antimicrobial peptides also have unique anticancer mechanisms, such as inducing apoptosis, autophagy, cell cycle arrest, membrane destruction, and inhibition of metastasis, which highlights the low drug resistance and high specificity of antimicrobial peptides. In this review, we summarize the related studies on antimicrobial peptides in the treatment of digestive tract tumors, mainly oral cancer, esophageal cancer, gastric cancer, liver cancer, pancreatic cancer, and colorectal cancer. This paper describes the therapeutic advantages of antimicrobial peptides due to their unique anticancer mechanisms. The length, net charge, and secondary structure of antimicrobial peptides can be modified by design or modification to further enhance their anticancer effects. In summary, as an emerging cancer treatment drug, antimicrobial peptides need to be further studied to realize their application in gastrointestinal cancer diseases.

Colorectal Liver Metastasis: Can Cytokines Make the Difference?

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide. Metastasis is the prime driver of CRC-related mortality, and the liver is the organ most frequently involved. Despite the overall success of current treatments, colorectal liver metastasis (CRLM) is associated with poor prognoses and a survival rate of only 14%. Recent studies have highlighted the importance of the tumor microenvironment (TME) and the crosstalk within it in determining the invasion of distant organs by circulating cancer cells. In the TME, cellular communication is mediated via soluble molecules, among which cytokines have recently emerged as key regulators, involved in every aspect of tumor progression and the metastatic cascade. Indeed, in the serum of CRC patients elevated levels of several cytokines are associated with cancer development and progression. The current review evaluates the role of different cytokines during CRLM development. Additionally, considering the increasing amount of data concerning the importance of cytokine complex networks, we outline the potential of combination treatments using targeted cytokines together with other well-established therapies, such as immune checkpoint blockades, chemotherapy, or gene therapy, to improve therapeutic outcomes.

A LIGHTFUL nanomedicine overcomes EGFR-mediated drug resistance for enhanced tyrosine-kinase-inhibitor-based hepatocellular carcinoma therapy

Targeting the activated epidermal growth factor receptor (EGFR) via clustered regularly interspaced short palindromic repeat (CRISPR) technology is appealing to overcome the drug resistance of hepatocellular carcinoma (HCC) towards tyrosine kinase inhibitor (TKI) therapy. However, combining these two distinct drugs using traditional liposomes results in a suboptimal synergistic anti-HCC effect due to the limited CRISPR/Cas9 delivery efficiency caused by lysosomal entrapment after endocytosis. Herein, we developed a liver-targeting gene-hybridizing-TKI fusogenic liposome (LIGHTFUL) that can achieve high CRISPR/Cas9 expression to reverse the EGFR-mediated drug resistance for enhanced TKI-based HCC therapy efficiently. Coated with a galactose-modified membrane-fusogenic lipid layer, LIGHTFUL reached the targeting liver site to fuse with HCC tumor cells, directly and efficiently transporting interior CDK5- and PLK1-targeting CRISPR/Cas9 plasmids (pXG333-CPs) into the HCC cell cytoplasm and then the cell nucleus for efficient expression. Such membrane-fusion-mediated pXG333-CP delivery resulted in effective downregulation of both CDK5 and PLK1, sufficiently inactivating EGFR to improve the anti-HCC effects of the co-delivered TKI, lenvatinib. This membrane-fusion-participant codelivery strategy optimized the synergetic effect of CRISPR/Cas9 and TKI combinational therapy as indicated by the 0.35 combination index in vitro and the dramatic reduction of subcutaneous and orthotopic TKI-insensitive HCC tumor growth in mice. Therefore, the established LIGHTFUL provides a unique co-delivery platform to combine gene editing and TKI therapies for enhanced synergetic therapy.

pH-Responsive and Actively Targeted Metal-Organic Framework Structures for Multimodal Antitumor Therapy and Inhibition of Tumor Invasion and Metastasis

Multimodal treatment is an important tool to overcome tumor drug resistance. The reactive oxygen species (ROS) generated by photodynamic therapy (PDT) can directly play a killing role on tumor cells, which has the advantages of repeatable treatment and no drug resistance. However, its therapeutic oxygen consumption and destruction of tumor microvessels lead to hypoxia in tumor tissues, and hypoxia leads to overexpression of the receptor tyrosine kinase (c-MET) and vascular endothelial growth factor receptor (VEGFR). Overexpression of these two receptors leads to increased tumor invasiveness and metastasis. The molecularly targeted drug cabozantinib (CAB) has multiple targets, including anti-c-MET and VEGFR, to inhibit the development of hepatocellular carcinoma (HCC). In this study, our team designed a pH-sensitive nanoparticle CAB/Ce6@ZIF-8@PEG-FA (CCZP) loaded with CAB and Ce6, which exerted a multimodal therapeutic effect of PDT and molecularly targeted therapy by laser irradiation, and the PDT-induced overexpression of MET and VEGFR could also be inhibited by the target of CAB, thus reducing the invasive tumor cells metastasis. In summary, CCZP gives full play to the advantages of both drugs, exerting multimodal treatment while reducing HCC invasion and metastasis, providing a safe, potential approach to clinical treatment.

Deciphering roles of TRIMs as promising targets in hepatocellular carcinoma: current advances and future directions

Tripartite motif (TRIM) family is assigned to RING-finger-containing ligases harboring the largest number of proteins in E3 ubiquitin ligating enzymes. E3 ubiquitin ligases target the specific substrate for proteasomal degradation via the ubiquitin-proteasome system (UPS), which seems to be a more effective and direct strategy for tumor therapy. Recent advances have demonstrated that TRIM genes associate with the occurrence and progression of hepatocellular carcinoma (HCC). TRIMs trigger or inhibit multiple biological activities like proliferation, apoptosis, metastasis, ferroptosis and autophagy in HCC dependent on its highly conserved yet diverse structures. Remarkably, autophagy is another proteolytic pathway for intracellular protein degradation and TRIM proteins may help to delineate the interaction between the two proteolytic systems. In depth research on the precise molecular mechanisms of TRIM family will allow for targeting TRIM in HCC treatment. We also highlight several potential directions warranted further development associated with TRIM family to provide bright insight into its translational values in hepatocellular carcinoma.

Water extract of frankincense and myrrh inhibits liver cancer progression and epithelial‑mesenchymal transition through Wnt/β‑catenin signaling

Wnt/β-catenin signaling is associated with epithelial-mesenchymal transformation (EMT), which serves an important role in hepatocellular carcinoma (HCC) invasion and metastasis. Frankincense and myrrh (FM) are antitumor agents commonly used in clinical practice. The present study aimed to investigate the effect and mechanism of water extract of FM on the progression of liver cancer cells. FM was applied to study its effects on HCC cell proliferation. Cell migration and invasion were evaluated by wound healing and Transwell assays. In addition, western blot was used to study the protein levels associated with EMT and Wnt/β-catenin signaling. The nuclear translocation of β-catenin was detected by immunofluorescence assay. A non-toxic dose of FM significantly inhibited invasion and metastasis of liver cancer cells. Furthermore, FM promoted expression of EMT marker E-cadherin, while decreasing expression of vimentin and N-cadherin. Finally, the protein and the nuclear staining levels of Disheveled 2 and β-catenin were both suppressed by water extract of FM. The water extract of FM inhibited the migration and invasion of liver cancer cells and inhibited EMT by suppressing activation of the Wnt/β-catenin signaling pathway.

Preoperative MRI features to predict vessels that encapsulate tumor clusters and microvascular invasion in hepatocellular carcinoma

OBJECTIVE

To estimate the potential of preoperative MRI features in the prediction of the integration patterns of vessels that encapsulate tumor clusters (VETC) and microvascular invasion (MVI) (VM) patterns in hepatocellular carcinoma (HCC) patients after resection and to assess the prognostic value of VM patterns.

MATERIALS AND METHODS

Patients who underwent surgical resection for HCC between July 2019 and July 2020 were retrospectively included in the training cohort and validation cohort. In the training cohort, patients were classified into VM-positive HCC (VM-HCC) and VM-negative HCC (non-VM HCC). Predictors associated with VM-HCC were determined by using logistic regression analyses and used to build a prediction model of VM-HCC. The model was tested in the validation cohort by area under the receiver operating characteristic curve (AUC) analysis. Prognostic factors associated with early recurrence of HCC were evaluated by use of Cox logistic regression analyses.

RESULTS

Alpha-fetoprotein (AFP) level higher than 400 ng/mL (odds ratio [OR] = 8.0; 95% CI: 2.6-25.2; P < 0.001), non-smooth tumor margin (OR = 3.1; 95% CI: 1.4-6.0; P < 0.001) and peritumoral arterial enhancement (OR = 2.9; 95% CI: 1.4-6.2; P = 0.004) were independent predictors of VM-HCC. The AUCs of the prediction model for VM-HCC were 0.81 for the training cohort and 0.79 for the validation cohort. The high risk of VM-HCC predicted by the three preoperative predictors derived from the prediction model (hazard ratio [HR] 2.0; 95% CI: 1.3, 3.2; P = 0.003) were independently associated with early recurrence, while pathologically confirmed VM-HCC (HR 2.8; 95% CI: 1.6, 3.8; P < 0.001) and satellite nodules (HR 1.8; 95% CI: 1.1, 3.1; P = 0.025) were independently associated with early recurrence after surgical resection.

CONCLUSION

The predictive model can be used to predict VM patterns. VM-HCC is associated with increased risk of early recurrence after surgical resection in HCC.

High blood galectin-3 level associated with risk of frailty in aging

Background

Frailty is one of the most problematic expressions of population aging, but its underlying mechanism has not been fully elucidated. Circulating galectin-3 (Gal-3) is involved in the pathogenesis of many age-related diseases. This study aims to explore the influence of circulating Gal-3 on the regulation of frailty and aging and to identify the potential mechanism further.

Methods

In this cross-sectional analysis, the Fried frailty phenotype (FP) was assessed among 149 community elderly residents in Shanghai. Peripheral blood mononuclear cells (PBMCs) were isolated by the Ficoll-Paque density gradient method, and differentially expressed genes (DEGs) encoding transcription factors in frailty were detected by Illumina and bioinformatics analyzed with R software. Gene Ontology (GO) enrichment analyses and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to explore the functional roles of these DEGs and the target genes related to frailty phenotypes. The serum Gal-3 concentration was tested by enzyme-linked immunosorbent assay (ELISA). Mouse frailty phenotype was used to construct an in vivo model of frailty, after which the serum levels of circulating Gal-3 and its gene expression levels in mouse tissues were determined.

Results

Participants' mean age was 72.04 ± 7.05 years. In total, 21.48% were frail and 36.91% were pre-frail. The mean serum Gal-3 concentration was 46.34 ± 17.99 ng/mL in frail participants, 32.30 ± 8.14 ng/mL in pre-frail participants, and 26.00 ± 5.87 ng/mL in non-frail individuals (p < 0.001). Significant positive correlations between serum Gal-3 level and FP score, SARC-F score, C-reactive protein (CRP), interleukin-6, etc., were observed. In addition, the KEGG pathway and GO enrichment analyses showed that 265 DEGs in PBMCs of frail participants were mainly related to inflammatory response, translation, RNA binding, protein binding, ribosome, and primary immunodeficiency. LGALS3 was identified as the overlapping gene between frailty-related DEGs and aging-related DEGs. The elevated serum Gal-3 concentration in the in vivo model of frailty was consistent with the results in participants.

Conclusion

In both community-dwelling older adults and aged mice, serum Gal-3 concentration was positively correlated with frailty. This circulating mediator may be a promising indicator of frailty.

Clinical trial registration

Chinese Clinical Trial Registry identifier, ChiCTR2000036399.

Mechanisms of tumor-associated macrophages affecting the progression of hepatocellular carcinoma

Tumor-associated macrophages (TAMs) are essential components of the immune cell stroma of hepatocellular carcinoma. TAMs originate from monocytic myeloid-derived suppressor cells, peripheral blood monocytes, and kupffer cells. The recruitment of monocytes to the HCC tumor microenvironment is facilitated by various factors, leading to their differentiation into TAMs with unique phenotypes. TAMs can directly activate or inhibit the nuclear factor-κB, interleukin-6/signal transducer and signal transducer and activator of transcription 3, Wnt/β-catenin, transforming growth factor-β1/bone morphogenetic protein, and extracellular signal-regulated kinase 1/2 signaling pathways in tumor cells and interact with other immune cells via producing cytokines and extracellular vesicles, thus affecting carcinoma cell proliferation, invasive and migratory, angiogenesis, liver fibrosis progression, and other processes to participate in different stages of tumor progression. In recent years, TAMs have received much attention as a prospective treatment target for HCC. This review describes the origin and characteristics of TAMs and their mechanism of action in the occurrence and development of HCC to offer a theoretical foundation for further clinical research of TAMs.

A negative feedback loop between KLF9 and the EMT program dictates metastasis of hepatocellular carcinoma

Metastasis is the primary cause of death of hepatocellular carcinoma (HCC), while the mechanism underlying this severe disease remains largely unclear. The Kruppel-like factor (KLF) family is one of the largest transcription factor families that control multiple physiologic and pathologic processes by governing the cellular transcriptome. To identify metastatic regulators of HCC, we conducted gene expression profiling on the MHCC97 cell series, a set of subclones of the original MHCC97 that was established by in vivo metastasis selection therefore harbouring differential metastatic capacities. We found that the expression of KLF9, a member of the KLF family, was dramatically repressed in the metastatic progeny clone of the MHCC97 cells. Functional studies revealed overexpression of KLF9 suppressed HCC migration in vitro and metastasis in vivo, while knockdown of KLF9 was sufficient to promote cell migration and metastasis accordingly. Mechanistically, we found the expression of KLF9 can reverse the pro-metastatic epithelial-mesenchymal transition (EMT) program via direct binding to the promoter regions of essential mesenchymal genes, thus repressing their expression. Interestingly, we further revealed that KLF9 was, in turn, directly suppressed by a mesenchymal transcription factor Slug, suggesting an intriguing negative feedback loop between KLF9 and the EMT program. Using clinical samples, we found that KLF9 was not only downregulated in HCC tissue compared to its normal counterparts but also further reduced in the HCC samples of whom had developed metastatic lesions. Together, we established a critical transcription factor that represses HCC metastasis, which is clinically and mechanically significant in HCC therapies.

M7G methylated core genes (METTL1 and WDR4) and associated RNA risk signatures are associated with prognosis and immune escape in HCC

N7 methylguanosine (m7G) has a crucial role the development of hepatocellular carcinoma (HCC). This study aimed to investigate the impact of the m7G methylation core genes (METTL1 and WDR4) and associated RNA risk signatures on HCC. we found m7G methylation core genes (METTL1 and WDR4) were upregulated in four HCC cell lines, and downregulation of METTL1 and WDR4 attenuated HCC cell proliferation, migration, and invasion. Moreover, METTL1 and WDR4 are upregulated in HCC tissues, and that there is a significant positive correlation between them. METTL1 and WDR4 were identified as independent prognostic markers for HCC by employing overall survival (OS), disease-specific survival (DSS), Progression Free Interval survival (PFI), and univariate/multivariate Cox analyses. We identified 1479 coding RNAs (mRNAs) and 232 long non-coding RNAs (lncRNAs) associated with METTL1 / WDR4 by using weighted coexpression network analysis (WGCNA) and co-clustering analysis. The least absolute shrinkage and selection operator (lasso) were used to constructing mRNA and lncRNA risk signatures associated with the METTL1 / WDR4. These risk were independent poor prognostic factors in HCC. Furthermore, we found that METTL1 / WDR4 expression and mRNA / lncRNA risk scores were closely associated with TP53 mutations. Clinicopathological features correlation results showed that METTL1 / WDR4 expression and mRNA / lncRNA risk score were associated with the stage and invasion depth (T) of HCC. To predict the overall survival of HCC individuals, we constructed a nomogram with METTL1/WDR4 expression, mRNA/lncRNA risk score, and clinicopathological features. In addition, we combined single-cell sequencing datasets and immune escape-related checkpoints to construct an immune escape-related protein-protein interaction(PPI) network. In conclusion, M7G methylated core genes (METTL1 and WDR4) and associated RNA risk signatures are associated with prognosis and immune escape in HCC.

Characterization of a novel peptide mined from the Red Sea brine pools and modified to enhance its anticancer activity

Drug resistance is a major cause of the inefficacy of conventional cancer therapies, and often accompanied by severe side effects. Thus, there is an urgent need to develop novel drugs with low cytotoxicity, high selectivity and minimal acquired chemical resistance. Peptide-based drugs (less than 0.5 kDa) have emerged as a potential approach to address these issues due to their high specificity and potent anticancer activity. In this study, we developed a support vector machine model (SVM) to detect the potential anticancer properties of novel peptides by scanning the American University in Cairo (AUC) Red Sea metagenomics library. We identified a novel 37-mer antimicrobial peptide through SVM pipeline analysis and characterized its anticancer potential through in silico cross-examination. The peptide sequence was further modified to enhance its anticancer activity, analyzed for gene ontology, and subsequently synthesized. To evaluate the anticancer properties of the modified 37-mer peptide, we assessed its effect on the viability and morphology of SNU449, HepG2, SKOV3, and HeLa cells, using an MTT assay. Additionally, we evaluated the migration capabilities of SNU449 and SKOV3 cells using a scratch-wound healing assay. The targeted selectivity of the modified peptide was examined by evaluating its hemolytic activity on human erythrocytes. Treatment with the peptide significantly reduced cell viability and had a critical impact on the morphology of hepatocellular carcinoma (SNU449 and HepG2), and ovarian cancer (SKOV3) cells, with a marginal effect on cervical cancer cell lines (HeLa). The viability of a human fibroblast cell line (1Br-hTERT) was also significantly reduced by peptide treatment, as were the proliferation and migration abilities of SNU449 and SKOV3 cells. The annexin V assay revealed programmed cell death (apoptosis) as one of the potential cellular death pathways in SNU449 cells upon peptide treatment. Finally, the peptide exhibited antimicrobial effects on both gram-positive and gram-negative bacterial strains. The findings presented here suggest the potential of our novel peptide as a potent anticancer and antimicrobial agent.

SMYD3 induces sorafenib resistance by activating SMAD2/3-mediated epithelial-mesenchymal transition in hepatocellular carcinoma

Drug resistance prominently hampers the effects of systemic therapy of sorafenib to hepatocellular carcinoma (HCC). Epigenetics have critical regulatory roles in drug resistance. However, the contributions of histone methylatransferase SET and MYND domain containing 3 (SMYD3) to sorafenib resistance in HCC remain largely unknown. Here, using our established sorafenib-resistant HCC cell and xenograft models, we found SMYD3 was markedly elevated in sorafenib-resistant tumors and cells. Functionally, loss- and gain-of-function studies showed that SMYD3 promoted the migration, invasion, metastasis and stemness of sorafenib-resistant HCC cells. Mechanistically, SMYD3 is required for SMAD2/3-mediated epithelial-mesenchymal transition (EMT) in sorafenib-resistant HCC cells by interacting with SMAD2/3 and epigenetically promoting the expression of SOX4, ZEB1, SNAIL1 and MMP9 genes. In summary, our data demonstrate that targeting SMYD3 is an effective approach to overcome sorafenib resistance in HCC.

CPEB2 Suppresses Hepatocellular Carcinoma Epithelial-Mesenchymal Transition and Metastasis through Regulating the HIF-1α/miR-210-3p/CPEB2 Axis

Hepatocellular carcinoma (HCC) is a prevalent and high-mortality cancer worldwide, and its complexity necessitates novel strategies for drug selection and design. Current approaches primarily focus on reducing gene expression, while promoting gene overexpression remains a challenge. In this work, we studied the effect of cytoplasmic polyadenylation element binding protein 2 (CPEB2) in HCC by constructing tissue microarrays (TAMs) from 90 HCC cases and corresponding para-cancerous tissues. Our analysis showed that CPEB2 expression was significantly reduced in HCC tissues, and its low expression was associated with a higher recurrence risk and poorer prognosis in patients with head and neck cancer. CPEB2 was found to regulate HCC epithelial-mesenchymal transition (EMT) and metastasis through the HIF-1α/miR-210-3p/CPEB2 feedback circuit. Using the RNA binding protein immunoprecipitation (RIP) assay, we demonstrated that miR-210 directly governs the expression of CPEB2. The inverse relationship between CPEB2 expression and miR-210-3p in HCC tissues suggested that this regulatory mechanism is directly linked to HCC metastasis, EMT, and clinical outcomes. Moreover, utilizing the SM2miR database, we identified drugs that can decrease miR-210-3p expression, consequently increasing CPEB2 expression and providing new insights for drug development. In conclusion, our findings illustrated a novel HIF-1α/miR-210-3p/CPEB2 regulatory signaling pathway in HCC and highlighted the potential of enhancing CPEB2 expression through targeting miR-210-3p as a novel predictive biomarker and therapeutic strategy in HCC, as it is modulated by the HIF-1α/miR-210-3p/CPEB2 feedback circuit.

TATA-box-binding protein promotes hepatocellular carcinoma metastasis through epithelial-mesenchymal transition

BACKGROUND

HCC characterizes malignant metastasis with high incidence and recurrence. Thus, it is pivotal to discover the mechanisms of HCC metastasis. TATA-box-binding protein (TBP), a general transcriptional factor (TF), couples with activators and chromatin remodelers to sustain the transcriptional activity of target genes. Here, we investigate the key role of TBP in HCC metastasis.

METHODS

TBP expression was measured by PCR, western blot, and immunohistochemistry. RNA-sequencing was performed to identify downstream proteins. Functional assays of TBP and downstream targets were identified in HCC cell lines and xenograft models. Luciferase reporter and chromatin immunoprecipitation assays were used to demonstrate the mechanism mediated by TBP.

RESULTS

HCC patients showed high expression of TBP, which correlated with poor prognosis. Upregulation of TBP increased HCC metastasis in vivo and in vitro, and muscleblind-like-3 (MBNL3) was the effective factor of TBP, positively related to TBP expression. Mechanically, TBP transactivated and enhanced MBNL3 expression to stimulate exon inclusion of lncRNA-paxillin (PXN)-alternative splicing (AS1) and, thus, activated epithelial-mesenchymal transition for HCC progression through upregulation of PXN.

CONCLUSIONS

Our data revealed that TBP upregulation is an HCC enhancer mechanism that increases PXN expression to drive epithelial-mesenchymal transition.

Comprehensive analysis of KLF2 as a prognostic biomarker associated with fibrosis and immune infiltration in advanced hepatocellular carcinoma

PURPOSE

Most Hepatocellular carcinoma (HCC) patients are in advanced or metastatic stage at the time of diagnosis. Prognosis for advanced HCC patients is dismal. This study was based on our previous microarray results, and aimed to explore the promising diagnostic and prognostic markers for advanced HCC by focusing on the important function of KLF2.

METHODS

The Cancer Genome Atlas (TCGA), Cancer Genome Consortium database (ICGC), and the Gene Expression Comprehensive Database (GEO) provided the raw data of this study research. The cBioPortal platform, CeDR Atlas platform, and the Human Protein Atlas (HPA) website were applied to analyze the mutational landscape and single-cell sequencing data of KLF2. Basing on the results of single-cell sequencing analyses, we further explored the molecular mechanism of KLF2 regulation in the fibrosis and immune infiltration of HCC.

RESULTS

Decreased KLF2 expression was discovered to be mainly regulated by hypermethylation, and indicated a poor prognosis of HCC. Single-cell level expression analyses revealed KLF2 was highly expressed in immune cells and fibroblasts. The function enrichment analysis of KLF2 targets indicated the crucial association between KLF2 and tumor matrix. 33-genes related with cancer associated fibroblasts (CAFs) were collected to identify the significant association of KLF2 with fibrosis. And SPP1 was validated as a promising prognostic and diagnostic marker for advanced HCC patients. CXCR6 CD8+ T cells were noted as a predominant proportion in the immune microenvironment, and T cell receptor CD3D was discovered to be a potential therapeutic biomarker for HCC immunotherapy.

CONCLUSION

This study identified that KLF2 is an important factor promoting HCC progression by affecting the fibrosis and immune infiltration, highlighting its great potential as a novel prognostic biomarker for advanced HCC.

Chromatin-associated OGT promotes the malignant progression of hepatocellular carcinoma by activating ZNF263

Reversible and dynamic O-GlcNAcylation regulates vast networks of highly coordinated cellular and nuclear processes. Although dysregulation of the sole enzyme O-GlcNAc transferase (OGT) was shown to be associated with the progression of hepatocellular carcinoma (HCC), the mechanisms by which OGT controls the cis-regulatory elements in the genome and performs transcriptional functions remain unclear. Here, we demonstrate that elevated OGT levels enhance HCC proliferation and metastasis, in vitro and in vivo, by orchestrating the transcription of numerous regulators of malignancy. Diverse transcriptional regulators are recruited by OGT in HCC cells undergoing malignant progression, which shapes genome-wide OGT chromatin cis-element occupation. Furthermore, an unrecognized cooperation between ZNF263 and OGT is crucial for activating downstream transcription in HCC cells. We reveal that O-GlcNAcylation of Ser662 is responsible for the chromatin association of ZNF263 at candidate gene promoters and the OGT-facilitated HCC malignant phenotypes. Our data establish the importance of aberrant OGT activity and ZNF263 O-GlcNAcylation in the malignant progression of HCC and support the investigation of OGT as a therapeutic target for HCC.

Phellodendronoside A Exerts Anticancer Effects Depending on Inducing Apoptosis Through ROS/Nrf2/Notch Pathway and Modulating Metabolite Profiles in Hepatocellular Carcinoma

Purpose

To reveal the potential mechanism of PDA on hepatocellular carcinoma SMMC-7721 cells in vitro.

Methods

The cytotoxic activity, colony formation, cell cycle distribution, apoptosis and their associated protein analysis, intracellular reactive oxygen species (ROS) and Ca²⁺ levels, proteins in Nrf2 and Ntoch pathways and metabolite profiles of PDA against hepatocellular carcinoma were investigated.

Results

PDA with cytotoxic activity inhibited cell proliferation and migration, increased intracellular ROS, Ca²⁺ levels and MCUR1 protein expression in a dose-dependent manner, caused cell cycle arrest in the S phase and induced apoptosis via adjusting the levels of Bcl-2, Bax, and Caspase 3 proteins, and inhibited the activation of Notch1, Jagged, Hes1, Nrf2 and HO-1 proteins. Metabonomics data showed that PDA significantly regulated 144 metabolite levels tend to be normal level, especially carnitine derivatives, bile acid metabolites associated with hepatocellular carcinoma, and mainly enriched in ABC transporter, arginine and proline metabolism, primary bile acid biosynthesis, Notch signaling pathway, etc, and proved that PDA markedly adjusted Notch signaling pathway.

Conclusion

PDA exhibited the proliferation inhibition of SMMC-7721 cells by inhibiting ROS/Nrf2/Notch signaling pathway and significantly affected the metabolic profile, suggesting PDA could be a potential therapeutic agent for patients with hepatocellular carcinoma.

The role of Vps4 in cancer development

VPS4 series proteins play a crucial role in the endosomal sorting complexes required for the transport (ESCRT) pathway, which is responsible for sorting and trafficking cellular proteins and is involved in various cellular processes, including cytokinesis, membrane repair, and viral budding. VPS4 proteins are ATPases that mediate the final steps of membrane fission and protein sorting as part of the ESCRT machinery. They disassemble ESCRT-III filaments, which are vital for forming multivesicular bodies (MVBs) and the release of intraluminal vesicles (ILVs), ultimately leading to the sorting and degradation of various cellular proteins, including those involved in cancer development and progression. Recent studies have shown a potential relationship between VPS4 series proteins and cancer. Evidence suggests that these proteins may have crucial roles in cancer development and progression. Several experiments have explored the association between VPS4 and different types of cancer, including gastrointestinal and reproductive system tumors, providing insight into the underlying mechanisms. Understanding the structure and function of VPS4 series proteins is critical in assessing their potential role in cancer. The evidence supporting the involvement of VPS4 series proteins in cancer provides a promising avenue for future research and therapeutic development. However, further researches are necessary to fully understand the mechanisms underlying the relationship between VPS4 series proteins and cancer and to develop effective strategies for targeting these proteins in cancer therapy. This article aims to review the structures and functions of VPS4 series proteins and the previous experiments to analyze the relationship between VPS4 series proteins and cancer.

m6A-mediated upregulation of LINC01003 regulates cell migration by targeting the CAV1/FAK signaling pathway in glioma

BACKGROUND

Long non-coding RNAs (lncRNAs) play important roles in the progression of glioma. Here, we examined the potential functions of a lncRNA, LINC01003, in glioma and characterized the underlying molecular mechanisms.

METHODS

The GEIPA2 and Chinese Glioma Genome Atlas (CCGA) databases were employed to analyze gene expression and the overall survival curve in patients with glioma. The functions of LINC01003 in glioma growth and migration were assessed by loss-of-function experiments in vitro and in vivo. RNA sequencing was used to determine the signaling pathways effected by LINC01003. Bioinformatics analysis and RNA immunoprecipitation (RIP) assays were used to explore the mechanism underlying the N6-methyladenine (m⁶A) modification-dependent upregulation of LINC01003 in glioma.

RESULTS

LINC01003 expression was upregulated in glioma cell lines and tissues. Higher LINC01003 expression predicted shorter overall survival time in glioma patients. Functionally, LINC01003 knockdown inhibited the cell cycle and cell proliferation and migration in glioma cells. Mechanistically, RNA sequencing revealed that LINC01003 mediated the focal adhesion signaling pathway. Furthermore, LINC01003 upregulation is induced by m⁶A modification regulated by METTL3.

CONCLUSION

This study characterized LINC01003 as a lncRNA that contributes to tumorigenesis in glioma and demonstrated that the LINC01003-CAV1-FAK axis serves as a potential therapeutic target for glioma.

Bone Lesion-Derived Extracellular Vesicles Fuel Prometastatic Cascades in Hepatocellular Carcinoma by Transferring ALKBH5-Targeting miR-3190-5p

Bone is the second leading metastatic site for hepatocellular carcinoma (HCC). Patients with HCC and bone metastasis suffer poor quality of life and reduced survival time. Extracellular vesicles (EVs) are widely involved in HCC formation and metastasis. However, the communication between primary HCC and bone lesions mediated by EVs remains unclear and the possible effect of bone metastasis on the progression of HCC remains largely unknown. Here, bone-metastasized HCC-derived EVs (BM-EVs) are found to localize to orthotropic HCC cells and promote HCC progression. Mechanistically, miR-3190-5p (miR-3190) is upregulated in intracellular HCC cells isolated from bone lesions as well as in their derived EVs. miR-3190 in BM-EVs is transferred into orthotopic tumor cells and enhances their metastatic capacity by downregulating AlkB homolog 5 (ALKBH5) expression. Decreased level of ALKBH5 exacerbates the prometastatic characteristics of HCC by modulating gene expression in N6-methyladenosine-dependent and -independent ways. Finally, antagomir-miR-3190-loaded liposomes with HCC affinity successfully suppress HCC progression in mice treated with BM-EVs. These findings reveal that BM-EVs initiate prometastatic cascades in orthotopic HCC by transferring ALKBH5-targeting miR-3190 and miR-3190 is serving as a promising therapeutic target for inhibiting the progression of HCC in patients with bone metastasis.

RNF8 depletion attenuates hepatocellular carcinoma progression by inhibiting epithelial-mesenchymal transition and enhancing drug sensitivity

Despite substantial advances that have been made in understanding the etiology of hepatocellular carcinoma (HCC), the early-stage diagnosis and treatment of advanced-stage HCC remain a major challenge. RNF8, an E3 ligase important for the DNA damage response, has been proven to facilitate the progression of breast and lung cancer, but its role in HCC remains unclear. In this study, we find that the expression of RNF8 is up-regulated in HCC tissues and positively correlated with poor prognosis of HCC. Furthermore, silencing RNF8 by siRNAs attenuates the migration of HCC cells and inhibits epithelial-mesenchymal transition (EMT) by regulating the expressions of proteins including N-cadherin, β-catenin, snail, and ZO-1. Moreover, Kaplan‒Meier survival analysis shows that high RNF8 expression predicts poor survival benefits from sorafenib. Finally, cell viability assay demonstrates that RNF8 depletion enhances the sensitivity of HCC cells to sorafenib and lenvatinib treatment. We hypothesize that the inhibitory role of RNF8 in EMT and its enhancing effects on anti-cancer drugs orchestrate the protective effects of RNF8 deficiency in HCC, which indicates its potential in clinical application.

PRAME Is a Novel Target of Tumor-Intrinsic Gas6/Axl Activation and Promotes Cancer Cell Invasion in Hepatocellular Carcinoma

(1) Background: Activation of the receptor tyrosine kinase Axl by Gas6 fosters oncogenic effects in hepatocellular carcinoma (HCC), associating with increased mortality of patients. The impact of Gas6/Axl signaling on the induction of individual target genes in HCC and its consequences is an open issue. (2) Methods: RNA-seq analysis of Gas6-stimulated Axl-proficient or Axl-deficient HCC cells was used to identify Gas6/Axl targets. Gain- and loss-of-function studies as well as proteomics were employed to characterize the role of PRAME (preferentially expressed antigen in melanoma). Expression of Axl/PRAME was assessed in publicly available HCC patient datasets and in 133 HCC cases. (3) Results: Exploitation of well-characterized HCC models expressing Axl or devoid of Axl allowed the identification of target genes including PRAME. Intervention with Axl signaling or MAPK/ERK1/2 resulted in reduced PRAME expression. PRAME levels were associated with a mesenchymal-like phenotype augmenting 2D cell migration and 3D cell invasion. Interactions with pro-oncogenic proteins such as CCAR1 suggested further tumor-promoting functions of PRAME in HCC. Moreover, PRAME showed elevated expression in Axl-stratified HCC patients, which correlates with vascular invasion and lowered patient survival. (4) Conclusions: PRAME is a bona fide target of Gas6/Axl/ERK signaling linked to EMT and cancer cell invasion in HCC.

Air pollution and liver cancer: A systematic review

Air pollution has previously been linked to several adverse health outcomes, but the potential association between air pollution and liver cancer remains unclear. We searched PubMed, EMBASE, and Web of Science from inception to 10 October 2021, and manually reviewed the references of relevant papers to further identify any related literature investigating possible associations between air pollution and liver cancer. Risk estimates values were represented by statistical associations based on quantitative analyses. A total of 13 cohort studies obtained from 11 articles were included, with 10,961,717 participants. PM_2.5 was the most frequently examined pollutant (included in 11 studies), followed by NO₂ and NO_x (included in 6 studies), and fewer studies focused on other pollutants (PM_{2.5 absorbance}, PM₁₀, PM_2.5-10, O₃, and BC). In all the 16 associations for liver cancer mortality, 14 associations reported the effect of PM_2.5 on liver cancer mortality. Eight associations on PM_2.5 were significant, showing a suggestive association between PM_2.5 and liver cancer mortality. Among 24 associations shown by risk estimates for liver cancer incidence, most associations were not statistically significant. For other air pollutants, no positive associations were presented in these studies. PM_2.5 was the most frequently examined pollutant, followed by NO₂ and NO_x, and fewer studies focused on other pollutants. PM_2.5 was associated with liver cancer mortality, but there was no association for other air pollutants. Future research should use advanced statistical methods to further assess the impact of multiple air pollutants on liver cancer in the changing socio-environmental context.

Update on Chemoresistance Mechanisms to First-Line Chemotherapy for Gallbladder Cancer and Potential Reversal Strategies

OBJECTIVE

Gallbladder cancer (GBC) mortality remains high and chemoresistance is increasing. This review consolidates what is known about the mechanisms of chemoresistance to inform and accelerate the development of novel GBC-specific chemotherapies.

METHODS

Studies related to GBC-related chemoresistance were systematically screened in PubMed using the advanced search function. Search terms included GBC, chemotherapy, and signaling pathway.

RESULTS

Analysis of existing studies showed that GBC has poor sensitivity to cisplatin, gemcitabine (GEM), and 5-fluorouracil. DNA damage repair-related proteins, including CHK1, V-SCR, and H2AX, are involved in tumor adaptation to drugs. GBC-specific chemoresistance is often accompanied by changes in the apoptosis and autophagy-related molecules, BCL-2, CRT, and GBCDRlnc1. CD44 + and CD133 + GBC cells are less resistant to GEM, indicating that tumor stem cells are also involved in chemoresistance. In addition, glucose metabolism, fat synthesis, and glutathione metabolism can influence the development of drug resistance. Finally, chemosensitizers such as lovastatin, tamoxifen, chloroquine, and verapamil are able improve the therapeutic effect of cisplatin or GEM in GBC.

CONCLUSIONS

This review summarizes recent experimental and clinical studies of the molecular mechanisms of chemoresistance, including autophagy, DNA damage, tumor stem cells, mitochondrial function, and metabolism, in GBC. Information on potential chemosensitizers is also discussed. The proposed strategies to reverse chemoresistance should inform the clinical use of chemosensitizers and gene-based targeted therapy for this disease.

Flavokawain A suppresses the vasculogenic mimicry of HCC by inhibiting CXCL12 mediated EMT

BACKGROUND

Hepatocellular carcinoma has high ability of vascular invasion and metastasis. Vasculogenic mimicry (VM) is closely related to the metastasis and recurrence of hepatocellular carcinoma (HCC). According to previous research, Chloranthus henryi has anti-tumor effect, but its molecular mechanism in the treatment of HCC has not yet been stated.

PURPOSE

In our study, we aimed to investigate the effect of the extract of Chloranthus henryi in HCC and its target and molecular mechanism. We hoped to explore potential drugs for HCC treatment.

STUDY DESIGN/METHODS

In this study, we isolated a chalcone compound from Chloranthus henryi, compound 4, identified as flavokawain A (FKA). We determined the anti-HCC effect of FKA by MTT and identified the target of FKA by molecular docking and CETSA. Hepatoma cells proliferation, migration, invasion, and VM formation were examined using EDU, wound healing, transwell, vasculogenic mimicry, and IF. WB, RT-PCR, and cell transfection were used to explore the mechanism of FKA on hepatoma cells. Tissue section staining is mainly used to demonstrate the effect of FKA on HCC in vivo.

RESULTS

We confirmed that FKA can directly interact with CXCL12 and HCC proliferation, migration, invasion, and VM formation were all inhibited through reversing the EMT progress in vitro and in vivo through the PI3K/Akt/NF-κB signaling pathway. Additionally, by overexpressing and knocking down CXCL12, we got the same results.

CONCLUSION

FKA attenuated proliferation, invasion and metastatic and reversed EMT in HCC via PI3K/Akt/HIF-1α/NF-κB/Twist1 pathway by targeting CXCL12. This study proposed that FKA may be a candidate drug and prospective strategy for HCC therapy.

KIFC3 regulates progression of hepatocellular carcinoma via EMT and the AKT/mTOR pathway

INTRODUCTION

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related deaths worldwide. Despite an overall downward trend in cancer mortality, HCC-related mortality continues to increase. KIFC3 is involved in cell division and cancers. However, the role of KIFC3 in HCC has yet to be elucidated.

METHODS

A total of 36 cases of HCC tissues, 4 HCC cell lines, and TCGA databases were searched to explore the expression of KIFC3 in HCC. Subsequently, Western blot analysis, immunofluorescence, bioinformatic analysis, molecular docking, and Co-IP were performed to investigate the molecular mechanisms of KIFC3 in HCC.

RESULT

We found that the expression of KIFC3 was upregulated in HCC, and high KIFC3 expression was related to poor overall survival. In addition, the knockdown of KIFC3 inhibited the proliferation, migration, and invasion of HCC cells in vitro, and impeded the growth of HCC in vivo, while overexpression of KIFC3 in HCC cells revealed the opposite effect. Mechanistically, KIFC3 promotes the progression of HCC through the PI3K/AKT/mTOR signalling. And KIFC3 had slight effect on the protein expression of p-PI3K, p-AKT and p-mTOR in TRIP13-ablated or LY294002-treated HCC cells. The KIFC3 knockdown could further enhance the inhibitory effect of LY294002.

CONCLUSION

Our data revealed that KIFC3 is upregulated in HCC and may serve as a novel biomarker for predicting survival in HCC patients. Targeting KIFC3 may serve as a novel therapeutic strategy for HCC patients.

Epithelial-mesenchymal transition-related gene prognostic index and phenotyping clusters for hepatocellular carcinoma patients

Epithelial-mesenchymal transition (EMT) contributes to high tumor heterogeneity and the immunosuppressive environment of the HCC tumor microenvironment (TME). Here, we developed EMT-related genes phenotyping clusters and systematically evaluated their impact on HCC prognosis, the TME, and drug efficacy prediction. We identified HCC specific EMT-related genes using weighted gene co-expression network analysis (WGCNA). An EMT-related genes prognostic index (EMT-RGPI) capable of effectively predicting HCC prognosis was then constructed. Consensus clustering of 12 HCC specific EMT-related hub genes uncovered two molecular clusters C1 and C2. Cluster C2 preferentially associated with unfavorable prognosis, higher stemness index (mRNAsi) value, elevated immune checkpoint expression, and immune cell infiltration. The TGF-β signaling, EMT, glycolysis, Wnt β-catenin signaling, and angiogenesis were markedly enriched in cluster C2. Moreover, cluster C2 exhibited higher TP53 and RB1 mutation rates. The TME subtypes and tumor immune dysfunction and exclusion (TIDE) score showed that cluster C1 patients responded well to immune checkpoint inhibitors (ICIs). Half-maximal inhibitory concentration (IC50) revealed that cluster C2 patients were more sensitive to chemotherapeutic and antiangiogenic agents. These findings may guide risk stratification and precision therapy for HCC patients.

BORIS variant SF2(C2/A4) promotes the malignant development of liver cancer by activating epithelial-mesenchymal transition and hepatic stellate cells

The underlying mechanisms of metastasis and recurrence of liver cancer remain largely unknown. Here, we found that Brother of the Regulator of Imprinted Sites (BORIS) variant SF2(C2/A4) was highly expressed in high metastatic potential hepatocellular carcinoma (HCC) cells and clinical tumor samples, related to the formation of satellite nodules. Its over expression promoted self-renewal, the expression of tumor stem cell markers, chemoresistance, wound healing rate, invasion and metastasis of HepG2 and Hep3B cells; reinforced epithelial-mesenchymal transition (EMT), decreased the expression of E-cadherin and increased N-cadherin and Vimentin. Subcellular localization experiment showed that BORIS SF2(C2/A4) was localized in nucleus and cytoplasm. Further double luciferase reporter gene experiment confirmed that it bound to TWIST1 gene promoter and significantly increased latter expression. BORIS SF2(C2/A4) knock down induced apoptosis of HCCLM3 and PLC/PRF/5 cells, and increased the protein content of cleaved caspase 3. Additionally, BORIS SF2(C2/A4) over expression increased the expression of fibroblast growth factor 2 (FGF2) in HepG2 and Hep3B cells. FGF2 expressed higher in HCC tumor tissues than in paired peri-tumor tissues, and its expression was positively correlated with BORIS SF2(C2/A4). Interestingly, high expression of FGF2 is also associated with the formation of satellite nodules. Moreover, using the medium from BORIS SF2(C2/A4) overexpressed cell lines to coculture hepatic stellate cell (HSCs) line LX-2, the latter could be activated and increased the expression of CD90 and PIGF, which is consistent with the effect of adding bFGF alone. These results indicate that BORIS SF2(C2/A4) plays a role in deterioration of liver cancer by regulating TWIST1 to induce EMT, and by FGF2 to activate HSCs.

SPRED2: A Novel Regulator of Epithelial-Mesenchymal Transition and Stemness in Hepatocellular Carcinoma Cells

The downregulation of SPRED2, a negative regulator of the ERK1/2 pathway, was previously detected in human cancers; however, the biological consequence remains unknown. Here, we investigated the effects of SPRED2 loss on hepatocellular carcinoma (HCC) cell function. Human HCC cell lines, expressing various levels of SPRED2 and SPRED2 knockdown, increased ERK1/2 activation. SPRED2-knockout (KO)-HepG2 cells displayed an elongated spindle shape with increased cell migration/invasion and cadherin switching, with features of epithelial-mesenchymal transition (EMT). SPRED2-KO cells demonstrated a higher ability to form spheres and colonies, expressed higher levels of stemness markers and were more resistant to cisplatin. Interestingly, SPRED2-KO cells also expressed higher levels of the stem cell surface markers CD44 and CD90. When CD44⁺CD90⁺ and CD44^-CD90^- populations from WT cells were analyzed, a lower level of SPRED2 and higher levels of stem cell markers were detected in CD44⁺CD90⁺ cells. Further, endogenous SPRED2 expression decreased when WT cells were cultured in 3D, but was restored in 2D culture. Finally, the levels of SPRED2 in clinical HCC tissues were significantly lower than those in adjacent non-HCC tissues and were negatively associated with progression-free survival. Thus, the downregulation of SPRED2 in HCC promotes EMT and stemness through the activation of the ERK1/2 pathway, and leads to more malignant phenotypes.

Multiplexed kinase interactome profiling quantifies cellular network activity and plasticity

Dynamic changes in protein-protein interaction (PPI) networks underlie all physiological cellular functions and drive devastating human diseases. Profiling PPI networks can, therefore, provide critical insight into disease mechanisms and identify new drug targets. Kinases are regulatory nodes in many PPI networks; yet, facile methods to systematically study kinase interactome dynamics are lacking. We describe kinobead competition and correlation analysis (kiCCA), a quantitative mass spectrometry-based chemoproteomic method for rapid and highly multiplexed profiling of endogenous kinase interactomes. Using kiCCA, we identified 1,154 PPIs of 238 kinases across 18 diverse cancer lines, quantifying context-dependent kinase interactome changes linked to cancer type, plasticity, and signaling states, thereby assembling an extensive knowledgebase for cell signaling research. We discovered drug target candidates, including an endocytic adapter-associated kinase (AAK1) complex that promotes cancer cell epithelial-mesenchymal plasticity and drug resistance. Our data demonstrate the importance of kinase interactome dynamics for cellular signaling in health and disease.

Exposure to polystyrene microplastics triggers lung injury via targeting toll-like receptor 2 and activation of the NF-κB signal in mice

Microplastics are ubiquitous pollutants with a wide range of plastic applications. More recently, microplastics are in the air and can be inhaled into the lungs, causing respiratory diseases. Knowledge of the underlying mechanisms by which microplastics may induce respiratory disease is still limited. This study used intranasal instillation to develop a model of lung injury. The histopathology result showed that the mouse lung had severe inflammatory responses, apoptosis and collagen deposition with chronic exposure to different sizes (Small: 1-5 μm and Large: 10-20 μm) of polystyrene microplastics (PS-MPS), and the damage of smaller sizes was obvious. The expression levels of the Toll-like receptors (TLRs) family, evolutionarily conserved pattern recognition receptors, were detected, and the levels of TLR2 mRNA was significantly increased. In transfection experiments, PS-MPS increased the inflammatory response in HEK293 cells with TLR2 expression. Furthermore, exposure to small polystyrene microplastics promoted oxidative stress and apoptosis, and accelerated the process of fibrosis. Interestingly, inhibition of the NF-κB signal relieves inflammation and oxidative stress, reduces apoptosis, and thus controls the fibrosis process. These results suggested that PS-MPS targeted binding to TLR2 and further exacerbated fibrosis by facilitating inflammation, oxidative stress, and apoptosis with the activation of NF-κB signal.

Aberrant DNA Methylation Patterns of Deleted in Liver Cancer 1 Isoforms in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), a common primary liver cancer, is the third leading cause of death worldwide. DNA methylation changes are common in HCC and have been studied to be associated with hepatocarcinogenesis. In our study, we used the MassARRAY^® EpiTYPER technology to investigate the methylation differences of deleted in liver cancer 1 (DLC1) (isoform 1 and 3) promoter between HCC tissues and corresponding adjacent noncancerous tissues and the association between methylation levels and clinicopathological features. In addition, the modified CRISPR-Cas9 system and the DNA methyltransferase inhibitor (DNMTi) were utilized to explore the functional correlation of epigenetic modifications and DLC1 gene regulation. The methylation levels of the DLC1 isoforms in HCC samples were found significantly lower than those in the adjacent noncancerous tissues (all p < 0.0001). Also, we found that the expression of DLC1 could be bidirectionally regulated by the modified CRISPR-Cas9 system and the DNMTi. Moreover, the hypomethylation of DLC1 in HCC samples was connected with the presence of satellite lesions (p = 0.0305) and incomplete tumor capsule (p = 0.0204). Receiver operator characteristic curve analysis demonstrated that the methylation levels of DLC1 could be applied to discriminate HCC patients (area under the curve = 0.728, p < 0.0001). The hypomethylation status was a key regulatory mechanism of DLC1 expression and might serve as a potential biomarker for HCC.

An Analysis Regarding the Association Between Proteasome (PSM) and Hepatocellular Carcinoma (HCC)

Background

The Proteasome (PSM) is a large multi-catalytic protease complex consisting of a 20S core particle and a 19S regulatory particle whose main function is to accept and degrade ubiquitinated substrates, are now considered as one of the potential regulators of tumor proliferation, and stemness maintenance. However, to date, studies on the relationship between PSM and hepatocellular carcinoma (HCC) are limited.

Methods

This study used a bioinformatics approach combining validation experiments to investigate the biological mechanisms that may be related with PSM. A series of experiments in vivo and in vitro were performed to explore the function of the 26S proteasome non-ATPase regulatory subunit 13 (PSMD13) in HCC.

Results

HCC patients can be divided into two clusters. Cluster 1 (C1) patients having a significantly worse prognosis than Cluster (C2). Two subtypes had significant differences in proliferation-related signaling. In particular, the frequency of TP53 mutation was significantly higher in C1 than in C2. In addition, PSM-associated genes were highly consistent with the expression of DNA repair-related signatures, suggesting a potential link between PSM and genomic instability. We also found that downregulation of PSMD13 expression significantly inhibited stemness of tumor cells and impaired the Epithelial mesenchymal transition (EMT) process. Finally, the correlation between the PSMD13 and Ki67 was found to be strong.

Conclusion

PSM is a valid predictor of prognosis and therapeutic response in patients with HCC disease. Furthermore, PSMD13 may be a potential therapeutic target.

Dynamic expression of H19 and MALAT1 and their correlation with tumor progression biomarkers in a multistage hepatocarcinogenesis model

Hepatocellular carcinoma (HCC) progresses sequentially in a stepwise pattern. Long noncoding RNA (lncRNA) can regulate the complex cascade of hepatocarcinogenesis. Our study aimed to elucidate the expression profile of H19 and MALAT1 during the different stages of hepatocarcinogenesis and the correlation between H19 and MALAT1 with the genes implicated in the carcinogenesis cascade. We employed a chemically induced hepatocarcinogenesis murine model to mimic the successive stages of human HCC development. Using real-time PCR, we analyzed the expression patterns of H19 and MALAT1, as well as the expression of biomarkers implicated in the Epithelial-Mesenchymal transition (EMT). The protein expression of the mesenchymal marker vimentin was also evaluated using immunohistochemistry in the stepwise induced stages. The histopathological evaluation of the liver tissue sections revealed significant changes during the experiment, with HCC developing at the final stage. Throughout the stages, there was a dynamic significant increase in the expression of H19 and MALAT1 compared to the normal control. Nevertheless, there was no significant difference between each stage and the preceding one. The tumor progression biomarkers (Matrix Metalloproteinases, vimentin, and β-catenin) exhibited the same trend of steadily increasing levels. However, in the case of Zinc finger E-box-binding homeobox 1 and 2 (ZEB1 and ZEB2), the significant elevation was only detected at the last stage of induction. The correlation between lncRNAs and the tumor progression biomarkers revealed a strong positive correlation between the expression pattern of H19 and MALAT1 with Matrix Metalloproteinases 2 and 9 and vimentin. Our findings imply that genetic and epigenetic alterations influence HCC development in a stepwise progressive pattern.

Portal vein tumor thrombosis in hepatocellular carcinoma: molecular mechanism and therapy

Portal vein tumor thrombosis (PVTT), a common complication of advanced hepatocellular carcinoma (HCC), remains the bottleneck of the treatments. Liver cancer cells potentially experienced multi-steps during PVTT process, including cancer cells leave from cancer nest, migrate in extracellular matrix, invade the vascular barrier, and colonize in the portal vein. Accumulated evidences have revealed numerous of molecular mechanisms including genetic and epigenetic regulation, cancer stem cells, immunosuppressive microenvironment, hypoxia, et al. contributed to the PVTT formation. In this review, we discuss state-of-the-art PVTT research on the potential molecular mechanisms and experimental models. In addition, we summarize PVTT-associated clinical trials and current treatments for PVTT and suppose perspectives exploring the molecular mechanisms and improving PVTT-related treatment for the future.

Whole-Transcriptome Sequencing Combined with High-Dimensional Proteomic Technologies Reveals the Potential Value of miR-135b-5p as a Biomarker for Hepatocellular Carcinoma

Purpose

Hepatocellular carcinoma (HCC) is a disease with great heterogeneity and a high mortality rate. It is crucial to identify reliable biomarkers for diagnosis, prognosis, and treatment to improve clinical outcomes in patients with HCC. Alpha-fetoprotein (AFP) is not only a widely used biomarker in clinical practice but also plays a complicated role in HCC, and it has recently been considered to be related to immunotherapy. MicroRNAs (miRNAs) are regarded as key regulators and promising biomarkers of HCC. We investigated the role of an AFP-related miRNA, miR-135b-5p, in HCC progression.

Methods

Identification of miR-135b-5p was performed based on a cohort of 65 HCC cases and the liver hepatocellular carcinoma cohort of The Cancer Genome Atlas (Asian people only). A combination of whole-transcriptome sequencing and high-dimensional proteomic technologies was used to study the role of miR-135b-5p in HCC.

Results

Upregulation of miR-135b-5p was detected in patients with HCC with high serum AFP levels (AFP > 400 ng/ml). Elevated miR-135b-5p expression was associated with adverse prognosis. We also identified the relevance between high miR-135b-5p expression and tumor-related pathological characteristics, such as Edmondson grade and vascular invasion. We revealed tyrosine kinase nonreceptor 1 as a potential target of miR-135b-5p. Additionally, the transcriptional start site of miR-135b-5p had potential binding sites for SRY-box transcription factor 9, and the stemness properties of tumor cells were more remarkable in HCC with the upregulation of miR-135b-5p. The molecular characterization of the miR-135b-5p-high group was similar to that of the HCC subclasses containing moderately and poorly differentiated tumors. Finally, gene signatures associated with improved clinical outcomes in immune checkpoint inhibitor therapy were upregulated in the miR-135b-5p-high group.

Conclusion

miR-135b-5p could be a biomarker for predicting the prognosis and antiprogrammed cell death protein 1 monotherapy response in HCC.

Identification of Potential Hub Genes Related to Aflatoxin B1, Liver Fibrosis and Hepatocellular Carcinoma via Integrated Bioinformatics Analysis

The molecular mechanism of the hepatotoxicant aflatoxin B1 to induce liver fibrosis and hepatocellular carcinoma (HCC) remains unclear, to offer fresh perspectives on the molecular mechanisms underlying the onset and progression of AFB1-Fibrosis-HCC, which may offer novel targets for the detection and therapy of HCC caused by AFB1. In this study, expression profiles of AFB1, liver fibrosis and liver cancer-related datasets were downloaded from the Gene Expression Omnibus (GEO), and differentially expressed genes (DEGs) were identified by the GEO2R tool. The STRING database, CytoHubba, and Cytoscape software were used to create the protein-protein interaction and hub genes of the combined genes, and the ssGSEA score for inflammatory cells related gene sets, the signaling pathway, and immunotherapy were identified using R software and the GSEA database. The findings revealed that AFB1-associated liver fibrosis and HCC combined genes were linked to cell process disruptions, the BUB1B and RRM2 genes were identified as hub genes, and the BUB1B gene was significantly increased in JAK-STAT signaling gene sets pathways as well as having an immunotherapy-related impact. In conclusion, BUB1B and RRM2 were identified as potential biomarkers for AFB1-induced fibrosis and HCC progression.

Potential Molecular Targeted Therapy for Unresectable Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most prevalent and lethal cancers, representing a serious worldwide health concern. The recurrence incidence of hepatocellular carcinoma (HCC) following surgery or ablation is as high as 70%. Thus, the clinical applicability of standard surgery and other locoregional therapy to improve the outcomes of advanced HCC is restricted and far from ideal. The registered trials did not identify a treatment that prolonged recurrence-free survival, the primary outcome of the majority of research. Several investigator-initiated trials have demonstrated that various treatments extend patients' recurrence-free or overall survival after curative therapies. In the past decade, targeted therapy has made significant strides in the treatment of advanced HCC. These targeted medicines produce antitumour effects via specific signals, such as anti-angiogenesis or advancement of the cell cycle. As a typical systemic treatment option, it significantly improves the prognosis of this fatal disease. In addition, the combination of targeted therapy with an immune checkpoint inhibitor is redefining the paradigm of advanced HCC treatment. In this review, we focused on the role of approved targeted medicines and potential therapeutic targets in unresectable HCC.

MiR-652-3p promotes malignancy and metastasis of cancer cells via inhibiting TNRC6A in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) was one of the most prevalent life-threatening cancers. Metastasis is the leading cause of cancer-related death in HCC. MiRNAs play essential roles in cancer metastasis.

METHODS

Expression of miR-652-3p in HCC was assessed. Function experiments of miR-652-3p and trinucleotide repeat-containing gene 6A protein (TNRC6A) were performed both in vitro and in vivo. mRNA sequencing, PCR, and western blot were performed to verify the target genes and pathway of miR-652-3p. The lung metastasis and xenograft cancer model in nude mice was established to investigate the effects of the miR-652-3p and TRNC6A on tumor metastasis in vivo. The relationship between the expression of the miR-652-3p, TNRC6A and the prognosis of HCC patients was analyzed.

RESULTS

Upregulated miR-652-3p was found in the tumor tissues of HCC, especially in metastatic HCC patients. Overexpression of miR-652-3p promoted and knockdown of miR-652-3p suppressed HCC metastasis both in vitro and in vivo. MiR-652-3p promoted HCC metastasis via regulating the EMT pathway. TNRC6A was identified as a direct target of miR-652-3p, and the knockdown of TNRC6A restored repressed EMT and HCC metastasis caused by the inhibition of miR-652-3p. Clinical results revealed that high expression of miR-652-3p and low expression of TNRC6A were positively correlated to shortened overall survival and disease-free survival in HCC patients.

CONCLUSIONS

MiR-652-3p promotes EMT and HCC metastasis by inhibiting TNRC6A expression in HCC. MiR-652-3p and TNRC6A may serve as potential biomarkers to predict prognosis in HCC patients with metastasis.

Regulators, functions, and mechanotransduction pathways of matrix stiffness in hepatic disease

The extracellular matrix (ECM) provides physical support and imparts significant biochemical and mechanical cues to cells. Matrix stiffening is a hallmark of liver fibrosis and is associated with many hepatic diseases, especially liver cirrhosis and carcinoma. Increased matrix stiffness is not only a consequence of liver fibrosis but is also recognized as an active driver in the progression of fibrotic hepatic disease. In this article, we provide a comprehensive view of the role of matrix stiffness in the pathological progression of hepatic disease. The regulators that modulate matrix stiffness including ECM components, MMPs, and crosslinking modifications are discussed. The latest advances of the research on the matrix mechanics in regulating intercellular signaling and cell phenotype are classified, especially for hepatic stellate cells, hepatocytes, and immunocytes. The molecular mechanism that sensing and transducing mechanical signaling is highlighted. The current progress of ECM stiffness's role in hepatic cirrhosis and liver cancer is introduced and summarized. Finally, the recent trials targeting ECM stiffness for the treatment of liver disease are detailed.

ALKBH5 prevents hepatocellular carcinoma progression by post-transcriptional inhibition of PAQR4 in an m6A dependent manner

BACKGROUND

N6-methyladenosine (m6A) is a prevalent modification of mRNA and is known to play important roles in tumorigenesis in many types of cancer. The function of N6-methyladenosine (m6A) RNA methylation depends on a variety of methyltransferases and demethylases. AlkB homolog 5 (ALKBH5) is a demethylase, and its biological function has not been completely explored in HCC.

RESULTS

ALKBH5 is downregulated and has antitumor effects in HCC cells. In addition, Progestin and AdipoQ Receptor 4 (PAQR4) was identified as a downstream target of ALKBH5 based on transcriptome sequencing and validation studies. We found that ALKBH5 decreases PAQR4 mRNA and protein expression in an N6-methyladenosine (m6A)-dependent manner. The study also showed that ALKBH5 changes PAQR4 expression via the m6A reader IGF2BP1. In both in vivo and in vitro experiments, PAQR4 showed a strong association with the development of HCC. Finally, we found that PAQR4 interacts with AKT and enhances PI3K/AKT pathway activation.

CONCLUSIONS

ALKBH5 inhibits HCC growth by downregulating PAQR4 expression in an m6A-dependent manner, therefore suppressing PI3K/AKT pathway activation.

Classification of the mitochondrial ribosomal protein-associated molecular subtypes and identified a serological diagnostic biomarker in hepatocellular carcinoma

Purpose

The objective of this study was to sort out innovative molecular subtypes associated with mitochondrial ribosomal proteins (MRPs) to predict clinical therapy response and determine the presence of circulating markers in hepatocellular carcinoma (HCC) patients.

Methods

Using an unsupervised clustering method, we categorized the relative molecular subtypes of MRPs in HCC patients. The prognosis, biological properties, immune checkpoint inhibitor and chemotherapy response of the patients were clarified. A signature and nomogram were developed to evaluate the prognosis. Enzyme-linked immunosorbent assay (ELISA) measured serum mitochondrial ribosomal protein L9 (MRPL9) levels in liver disease patients and normal individuals. Receiver operating characteristic (ROC) curves were conducted to calculate the diagnostic effect. The Cell Counting Kit 8 was carried out to examine cell proliferation, and flow cytometry was used to investigate the cell cycle. Transwell assay was applied to investigate the potential of cell migration and invasion. Western blot detected corresponding changes of biological markers.

Results

Participants were classified into two subtypes according to MRPs expression levels, which were characterized by different prognoses, biological features, and marked differences in response to chemotherapy and immune checkpoint inhibitors. Serum MRPL9 was significantly higher in HCC patients than in normal individuals and the benign liver disease group. ROC curve analysis showed that MRPL9 was superior to AFP and Ferritin in differentiating HCC from healthy and benign patients, or alone. Overexpressed MRPL9 could enhance aggressiveness and facilitate the G1/S progression in HCC cells.

Conclusion

We constructed novel molecular subtypes based on MRPs expression in HCC patients, which provided valuable strategies for the prediction of prognosis and clinical personalized treatment. MRPL9 might act as a reliable circulating diagnostic biomarker and therapeutic target for HCC patients.

Current view of liver cancer cell-of-origin and proposed mechanisms precluding its proper determination

Hepatocellular carcinoma and intrahepatic cholangiocarcinoma are devastating primary liver cancers with increasing prevalence in many parts of the world. Despite intense investigation, many aspects of their biology are still largely obscure. For example, numerous studies have tackled the question of the cell-of-origin of primary liver cancers using different experimental approaches; they have not, however, provided a clear and undisputed answer. Here, we will review the evidence from animal models supporting the role of all major types of liver epithelial cells: hepatocytes, cholangiocytes, and their common progenitor as liver cancer cell-of-origin. Moreover, we will also propose mechanisms that promote liver cancer cell plasticity (dedifferentiation, transdifferentiation, and epithelial-to-mesenchymal transition) which may contribute to misinterpretation of the results and which make the issue of liver cancer cell-of-origin particularly complex.

Mesenchymal circulating tumor cells and Ki67: their mutual correlation and prognostic implications in hepatocellular carcinoma

BACKGROUND

Mesenchymal circulating tumor cells (M-CTCs) may be related to tumor progression, and Ki67 expression is known to be involved in tumor proliferation. The aim of the present study was to explore the relationship between M-CTCs and Ki67 in hepatocellular carcinoma (HCC) and their ability to predict prognosis.

METHODS

Peripheral blood samples were obtained from 105 HCC patients before radical surgery. CTCs were isolated using CanPatrol enrichment and classified via in situ hybridization. Ki67 expression in HCC tissue was assessed through immunohistochemistry. Potential relationships of M-CTC, Ki67 with clinicopathological factors and prognosis were evaluated. Overall survival (OS) was analyzed using the Kaplan-Meier method and Cox regression. The prognostic efficacy of M-CTC, Ki67 and both together (M-CTC + Ki67) was assessed in terms of time-dependent receiver operating characteristic (ROC) curves and Harrell's concordance index.

RESULTS

Of the 105 patients, 50 were positive for M-CTCs (count ≥ 1 per 5 mL) and 39 showed high Ki67 expression (≥ 50% tumor cells were Ki67-positive). The presence of M-CTC was significantly associated with alpha-fetoprotein (AFP) ≥ 400 ng/mL (P = 0.007), tumor size ≥ 5 cm (P = 0.023), multiple tumors (P < 0.001), poorly differentiated tumors (P = 0.003), incomplete tumor capsule (P < 0.001), Barcelona Clinic liver cancer (BCLC) stage B or C (P < 0.001), microvascular invasion (MVI) (P = 0.05) and portal vein tumor thrombosis (PVTT) (P = 0.006). High Ki67 expression correlated with AFP ≥ 400 ng/mL (P = 0.015), tumor size ≥ 5 cm (P = 0.012), incomplete tumor capsule (P < 0.001), MVI (P = 0.001), PVTT (P = 0.003), advanced BCLC stage (P = 0.01), and vessel carcinoma embolus (VCE) (P = 0.001). M-CTC positively correlated with Ki67. Patients positive for M-CTCs had a significantly shorter OS than patients negative for them. Similarly, high Ki67 expression was associated with a significantly lower OS. The high-risk group (positive for M-CTCs and high Ki67 expression) had worse OS than the other groups (P < 0.0001). Uni- and multivariate analyses showed that OS was independently predicted by M-CTC [hazard ratio (HR) 1.115; P < 0.001], Ki67 (HR 1.666; P = 0.046) and the combination of both (HR 2.885; P = 0.008). Based on ROC curves and the concordance index, the combination of M-CTC and Ki67 was superior to either parameter alone for predicting the OS of HCC patients.

CONCLUSIONS

The presence of M-CTC correlates with high Ki67 expression in HCC patients, and both factors are associated with poor prognosis. Furthermore, the combination of M-CTC and Ki67 is a useful prognostic indicator for predicting OS in patients with HCC after hepatectomy, performing better than either parameter on its own.

ATP13A2 is a Prognostic Biomarker and Correlates with Immune Infiltrates in Hepatocellular Carcinoma

PURPOSE

To explore the expression and role of ATPase cation transporting 13A2 (ATP13A2) on hepatocellular carcinoma (HCC) progression and prognosis.

METHODS

The level of ATP13A2 in 63 HCC tissues was evaluated by quantitative real-time polymerase chain reaction, Western blot, and immunohistochemistry. Then, the prognostic value of ATP13A2 for HCC was explored. GO and KEGG pathway enrichments were performed to predict ATP13A2-mediated biological functions. Besides, the correlations between ATP13A2 and key regulators involved in cell cycle and metastasis, the status of different tumor-infiltrating immune cells was investigated.

RESULTS

ATP13A2 was frequently upregulated in 63 HCC tissues relatively to matched non-tumor tissues. The level of ATP13A2 significantly correlated with tumor stage and tumor grade. HCC patients with higher levels of ATP13A2 had a worse prognosis. Moreover, multivariate survival analysis supported ATP13A2 to be an independent prognostic factor for HCC. GO and KEGG analysis indicated a potential role of ATP13A2 on regulating cell cycle, metastasis, and immune infiltrates. Especially, the level of ATP13A2 was positively correlated with CCNB1, CCND3, CDC25B, CDK4, Vimentin, MMP9, MMP14, and LMNB2. A positive correlation was noticed between ATP13A2 and infiltration levels of B cells, CD8⁺ T cells, CD4⁺ T cells, macrophages, neutrophils, dendritic cells, monocytes, M2 macrophages, and exhausted T cells in HCC.

CONCLUSION

Upregulation of ATP13A2 is a common feature as well as an independent prognostic biomarker for HCC. ATP13A2 are associated with key regulators involved in cell cycle, metastasis, and immune infiltrates in HCC, and may act as a potential immunotherapy target for HCC.

Comprehensive Genomic Profiling Identifies FAT1 as a Negative Regulator of EMT, CTCs, and Metastasis of Hepatocellular Carcinoma

Background

FAT atypical cadherin 1 (FAT1) acts as a tumor suppressor or oncogene, which regulates cell adherence, proliferation, motility, and actin kinetics. FAT1 gene expression is closely related to hepatocarcinogenesis; however, the function and mechanism of FAT1 in hepatocellular carcinoma (HCC) remain unclear.

Methods

Here, we screened for the FAT1, which is intimately linked to the development and progression of HCC, both in circulating tumor cells (CTCs) and tumor tissues using next generation sequencing (NGS). Immunohistochemical staining was performed to detect FAT1 protein expression. To determine the impact of FAT1 on epithelial-mesenchymal transition (EMT), migration and invasion of HCC, an in vitro transwell assay and Western blot were performed. Moreover, Gene Set Enrichment Analysis was carried out to discover the underlying mechanism. Finally, animal experiments were conducted to confirm the effects of FAT1 on HCC metastasis and tumorigenicity.

Results

Our results showed that FAT1 expression was decreased in HCC tissues, while in vitro and in vivo, the FAT1 knockdown facilitated invasion, cell motility, colony formation, and proliferation. FAT1 knockdown also resulted in decreased expression of E-cadherin and markedly elevated expression of N-cadherin, vimentin, and snail. We also confirmed our hypothesis from the analysis of group differences in the CTC phenotype and lung metastasis in nude mice.

Conclusion

Our findings illustrated that FAT1 played a negative regulatory role in the HCC EMT and metastasis, providing further evidence for the role played by FAT1 in the formation and progression of HCC.

Inhibition of Annexin A10 Contributes to ZNF281 Mediated Aggressiveness of Hepatocellular Carcinoma

Objective

To investigate the involvement and transcriptional targets of zinc finger protein 281 (ZNF281) in the progression of hepatocellular carcinoma (HCC).

Methods

The expression of ZNF281 in HCC was detected in tissue microarray and cell lines. The role of ZNF281 in aggressiveness of HCC was examined using wound healing, matrigel transwell, pulmonary metastasis model and assays for expression of EMT markers. RNA-seq was used to find potential target gene of ZNF281. Chromatin immunoprecipitation (ChIP) assay and co-immunoprecipitation (Co-IP) were employed to uncover the mechanism of the transcriptional regulation of ZNF281 on the target gene.

Results

ZNF281 was increased in tumor tissues and positively correlated with vascular invasion in HCC. Knockdown of ZNF281 suppressed the migration and invasion with significant alteration of EMT marker expression in HLE and Huh7 HCC cell lines. RNA-seq screening showed that the tumor suppressor gene Annexin A10 (ANXA10) was a most up-regulated gene in response to ZNF281 depletion and responsible for the attenuation of aggressiveness. Mechanistically, ZNF281 interacted with the ANXA10 promoter region harboring ZNF281 recognition sites, and recruited components of nucleosome remodeling and deacetylation (NuRD) complex. By knocking down such components like HDAC1 or MTA1, ANXA10 was released from transcriptional repression by ZNF281/NuRD, and in turn reversed the EMT, invasion and metastasis driven by ZNF281.

Conclusion

ZNF281 drives invasion and metastasis of HCC partially through transcriptional repression of tumor suppressor gene ANXA10 by recruiting NuRD complex.

A micropeptide JunBP regulated by TGF-β promotes hepatocellular carcinoma metastasis

Transforming growth factor beta (TGF-β) signaling pathway plays important roles in hepatocellular carcinoma (HCC) progression. Long intergenic non-protein coding RNAs (lincRNAs) are important components of TGF-β signaling pathway and perform their functions through different mechanisms. Here, we found that LINC02551 was activated by TGF-β transcriptionally and identified a 174-amino-acid peptide, Jun binding micropeptide (JunBP), encoded by LINC02551 in HCC tissues and HCC cell lines. Functional study showed that JunBP promotes HCC metastasis through binding to c-Jun and subsequent promotion of its phosphorylated activation. Activated c-Jun has higher binding affinity to SMAD3, which in turn leads to more SMAD3 recruited to the promoter region of LINC02551. We find a positive feedback among them, and this mechanism provides a novel potential prognostic biomarker and therapeutic target in HCC.