Hepatocellular Carcinoma: Updates in Pathogenesis, Detection and Treatment

SIRT4 is associated with microvascular infiltration, immune cell infiltration, and epithelial mesenchymal transition in hepatocellular carcinoma

AIMS

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. In the present study, we evaluated SIRT4 expression levels in HCC specimens and investigated the relationships between SIRT4 expression levels, clinicopathological factors, and microvascular infiltration (MVI) in HCC.

METHODS

The expression levels of SIRT4 in 108 HCC specimens were examined by immunohistochemical staining. MVI in HCC specimens was divided into three subtypes: M0, M1, and M2. Comprehensive bioinformatics analysis was carried out to demonstrate SIRT4's biological functions and expression-related prognostic value.

RESULTS

The diffuse cytoplasmic expression pattern of SIRT4 was observed in all adjacent nonneoplastic liver tissues. The levels of SIRT4 were higher in HCC than in any other type of cancer and normal tissues. In addition, the expression levels of SIRT4 were significantly decreased in HCC tissues when MVI was M1 or M2 (p=0.003) but were not related to the overall clinical outcome. To explain MVI regulated by SIRT4, we also found that SIRT4 expression correlated with epithelial-mesenchymal transition (EMT) markers and CD4+ T/NK cells and downregulated cancer-associated fibroblast cells. Also, there was a significant relationship between MVI and degree of cell differentiation (p=0.003), tumor size (p<0.001), alpha fetoprotein (AFP) (p=0.001), alanine aminotransferase (ALT) (p=0.024), and γ-glutamyl transferase (γ-GT) (p=0.024). However, SIRT4 was not an independent prognostic marker of HCC.

CONCLUSIONS

Our results demonstrated an association between SIRT4 expression levels, MVI, immune cell infiltration, and potential biological functions, including EMT in the progression of HCC.

The current landscape of therapies for hepatocellular carcinoma

Globally, primary liver cancer is the third leading cause of cancer-related deaths, with approximately 830 000 deaths worldwide in 2020, accounting for 8.3% of total deaths from all cancer types (1). This disease disproportionately affects those in countries with low or medium Human Development Index scores in Eastern Asia, South-Eastern Asia, and Northern and Western Africa (2). Hepatocellular carcinoma (HCC), the most common type of primary liver cancer, often develops in the background of chronic liver disease, caused by hepatitis B or C virus, non-alcoholic steatohepatitis (NASH), or other diseases that cause cirrhosis. Prognosis can vary dramatically based on number, size, and location of tumors. Hepatic synthetic dysfunction and performance status (PS) also impact survival. The Barcelona Clinic Liver Cancer (BCLC) staging system best accounts for these variations, providing a reliable prognostic stratification. Therapeutic considerations of this complex disease necessitate a multidisciplinary approach and can range from curative-intent surgical resection, liver transplantation or image-guided ablation to more complex liver-directed therapies like transarterial chemoembolization (TACE) and systemic therapy. Recent advances in the understanding of the tumor biology and microenvironment have brought new advances and approvals for systemic therapeutic agents, often utilizing immunotherapy or VEGF-targeted agents to modulate the immune response. This review will discuss the current landscape in the treatments available for early, intermediate, and advanced stage HCC.

STING pathway contributes to the prognosis of hepatocellular carcinoma and identification of prognostic gene signatures correlated to tumor microenvironment

Background

Hepatocellular carcinoma (HCC) is one of the most malignant solid tumors worldwide. Recent evidence shows that the stimulator of interferon genes (STING) pathway is essential for anti-tumor immunity via inducing the production of downstream inflammatory cytokines. However, its impact on the prognosis and tumor microenvironment of HCC was still limited known.

Methods

We obtained gene expression profiles of HCC from GEO, TCGA, and ICGC databases, and immune-related genes (IRGs) from the ImmPort database. Multivariate Cox regression was performed to identify independent prognostic factors. Nomogram was established to predict survival probability for individual patients. Kaplan–Meier curve was used to evaluate the survival difference. Afterward, ESTIMATE, TISCH, and TIMER databases were combined to assess the immune cell infiltration. Furthermore, the qPCR, western blotting, and immunohistochemistry were done to evaluate gene expression, and in vitro cell models were built to determine cell migratory ability.

Results

We found that gene markers of NLRC3, STING1, TBK1, TRIM21, and XRCC6 within STING pathway were independent prognostic factors in HCC patients. Underlying the finding, a predictive nomogram was constructed in TCGA-training cohort and further validated in TCGA-all and ICGC datasets, showing credible performance. Experimentally, up-regulated TBK1 promotes the ability of HCC cell migration. Next, the survival-related immune-related co-expressed gene signatures (IRCGS) (VAV1, RHOA, and ZC3HAV1) were determined in HCC cohorts and their expression was verified in human HCC cells and clinical samples. Furthermore, survival-related IRCGS was associated with the infiltration of various immune cell subtypes in HCC, the transcriptional expression of prominent immune checkpoints, and immunotherapeutic response.

Conclusion

Collectively, we constructed a novel prognostic nomogram model for predicting the survival probability of individual HCC patients. Moreover, an immune-related prognostic gene signature was determined. Both might function as potential therapeutic targets for HCC treatment in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02734-4.

Traditional Chinese medicine: An important source for discovering candidate agents against hepatic fibrosis

Hepatic fibrosis (HF) refers to the pathophysiological process of connective tissue dysplasia in the liver caused by various pathogenic factors. Nowadays, HF is becoming a severe threat to the health of human being. However, the drugs available for treating HF are limited. Currently, increasing natural agents derived from traditional Chinese medicines (TCMs) have been found to be beneficial for HF. A systemic literature search was conducted from PubMed, GeenMedical, Sci-Hub, CNKI, Google Scholar and Baidu Scholar, with the keywords of "traditional Chinese medicine," "herbal medicine," "natural agents," "liver diseases," and "hepatic fibrosis." So far, more than 76 natural monomers have been isolated and identified from the TCMs with inhibitory effect on HF, including alkaloids, flavones, quinones, terpenoids, saponins, phenylpropanoids, and polysaccharides, etc. The anti-hepatic fibrosis effects of these compounds include hepatoprotection, inhibition of hepatic stellate cells (HSC) activation, regulation of extracellular matrix (ECM) synthesis & secretion, regulation of autophagy, and antioxidant & anti-inflammation, etc. Natural compounds and extracts from TCMs are promising agents for the prevention and treatment of HF, and this review would be of great significance to development of novel drugs for treating HF.

Midnolin Regulates Liver Cancer Cell Growth In Vitro and In Vivo

Hepatocellular carcinoma (HCC) ranks worldwide as one of the most lethal cancers. In spite of the vast existing knowledge about HCC, the pathogenesis of HCC is not completely understood. Discovery of novel genes that contribute to HCC pathogenesis will provide new insights for better understanding and treating HCC. The relatively obscure gene midnolin has been studied for over two decades; however, its biological roles are largely unknown. Our study is the first to demonstrate the functional significance of midnolin in HCC/cancer: Midnolin expression correlates with poor prognosis in HCC patients, and suppression of midnolin severely inhibits tumorigenicity of HCC cells in vitro and in mice and disrupts retinoic acid/lipid metabolism in these cells.

The role of BCL9 genetic variation as a biomarker for hepatitis C-related hepatocellular carcinoma in Egyptian patients

BACKGROUND

Hepatocellular carcinoma (HCC) is considered one of the most common cancers related to mortality around the world, and susceptibility is related with genetic, lifestyle, and environmental factors. Copy number variation of the Bcell CLL/lymphoma 9 (BCL9) gene is a type of structural variation which can influence gene expression and can be related with specific phenotypes and diseases and has a role in hepatocarcinogenesis. Our aims were to assess the copy number variation (CNV) in the BCL9 gene and explore its role in HCV-related HCC Egyptian patients. A total of 50 HCV-related HCC patients were enrolled in the study (including 25 early HCC and 25 late HCC cases); the copy number of the BCL9 gene was detected using quantitative polymerase reaction.

RESULTS

There was a highly statistically significant difference between the two groups (early and late HCC patients) in gender, bilharziasis, performance status, child score class, child grade, focal lesion size, portal vein, and ascites. CNV was detected and represented by the gain in the BCL9 gene in 14% of patients, and all of them were males. Also, it was noticed that the ratio of gain in BCL9 copy number in late individuals was about 1.5 times than that in early HCC individuals. Moreover, our results showed that the distribution of performance status > 1, average and enlarged liver, focal lesion size, thrombosed portal vein, and AFP was higher in patients with BCL9 copy number gain.

CONCLUSION

We detected about 14% gain in BCL9 copy number in Egyptian HCC patients. But the variation in copy number of the BCL9 gene did not affect HCC development in our patients' cohort.

Downregulation of Methionine Cycle Genes MAT1A and GNMT Enriches Protein-Associated Translation Process and Worsens Hepatocellular Carcinoma Prognosis

The major biological methyl donor, S-adenosylmethionine (adoMet) synthesis occurs mainly in the liver. Methionine adenosyltransferase 1A (MAT1A) and glycine N-methyltransferase (GNMT) are two key enzymes involved in the functional implications of that variation. We collected 42 RNA-seq data from paired hepatocellular carcinoma (HCC) and its adjacent normal liver tissue from the Cancer Genome Atlas (TCGA). There was no mutation found in MAT1A or GNMT RNA in the 42 HCC patients. The 11,799 genes were annotated in the RNA-Seq data, and their expression levels were used to investigate the phenotypes of low MAT1A and low GNMT by Gene Set Enrichment Analysis (GSEA). The REACTOME_TRANSLATION gene set was enriched and visualized in a heatmap along with corresponding differences in gene expression between low MAT1A versus high MAT1A and low GNMT versus high GNMT. We identified 43 genes of the REACTOME_TRANSLATION gene set that are powerful prognosis factors in HCC. The significantly predicted genes were referred into eukaryotic translation initiation (EIF3B, EIF3K), eukaryotic translation elongation (EEF1D), and ribosomal proteins (RPs). Cell models expressing various MAT1A and GNMT proved that simultaneous restoring the expression of MAT1A and GNMT decreased cell proliferation, invasion, as well as the REACTOME_TRANSLATION gene EEF1D, consistent with a better prognosis in human HCC. We demonstrated new findings that downregulation or defect in MAT1A and GNMT genes can enrich the protein-associated translation process that may account for poor HCC prognosis. This is the first study demonstrated that MAT1A and GNMT, the 2 key enzymes involved in methionine cycle, could attenuate the function of ribosome translation. We propose a potential novel mechanism by which the diminished GNMT and MAT1A expression may confer poor prognosis for HCC.

Integrated Proteomics and Bioinformatics to Identify Potential Prognostic Biomarkers in Hepatocellular Carcinoma

BACKGROUND

Liver hepatocellular carcinoma (HCC) is the third most common cause of death by cancer and has a high mortality world-widely. Approximately 75-85% of primary liver cancers are caused by HCC. Uncovering novel genes with prognostic significance would shed light on improving the HCC patient's outcome.

OBJECTIVE

In this research, we aim to identify novel prognostic biomarkers in hepatocellular carcinoma.

METHODS

Integrated proteomics and bioinformatics analysis were performed to investigate the expression landscape of prognostic biomarkers in 24 paired HCC patients.

RESULTS

As a result, eight key genes related to prognosis, including ACADS, HSD17B13, PON3, AMDHD1, CYP2C8, CYP4A11, SLC27A5, CYP2E1, were identified by comparing the weighted gene co-expression network analysis (WGCNA), proteomic differentially expressed genes (DEGs), proteomic turquoise module, The Cancer Genome Atlas (TCGA) cohort DEGs of HCC. Furthermore, we trained and validated eight pivotal genes integrating these independent clinical variables into a nomogram with superior accuracy in predicting progression events, and their lower expression was associated with a higher stage/risk score. The Gene Set Enrichment Analysis (GSEA) further revealed that these key genes showed enrichment in the HCC regulatory pathway.

CONCLUSION

All in all, we found that these eight genes might be the novel potential prognostic biomarkers for HCC and also provide promising insights into the pathogenesis of HCC at the molecular level.

Hepatocellular Carcinoma Risk According to Regimens for Eradication of Hepatitis C Virus; Interferon or Direct Acting Antivirals

By pegylated interferon (PegIFN)-free direct-acting antivirals (DAAs) against hepatitis C virus (HCV) infection, a sustained virological response (SVR) rate >95% can be attained with a satisfactory tolerability and shorter treatment duration. However, it remains controversial whether there is any difference in prognosis depending on regimens-PegIFN or DAAs. We compared the probabilities of hepatocellular carcinoma (HCC) development between patients achieving an SVR by PegIFN/ribavirin (PegIFN group, n = 603) and DAAs (DAAs group, n = 479). The DAAs group was significantly older and had a higher proportion of cirrhosis than the PegIFN group. Before adjustment, the DAAs group had a higher HCC incidence than the PegIFN group (p < 0.001). However, by multivariate analyses, the DAAs (vs. PegIFN) group was not associated with HCC risk (adjusted hazard ratio 0.968, 95% confidence interval 0.380-2.468; p = 0.946). Old age, male, higher body mass index, cirrhosis, and lower platelet count were associated with increased HCC risk (all p < 0.05). After propensity score matching (PSM), a similar HCC risk between the two groups was observed (p = 0.372). We also compared HCC incidences according to sofosbuvir (SOF)-based and SOF-free DAAs, showing a similar risk in both groups before adjustment (p = 0.478) and after PSM (p = 0.855). In conclusion, post-SVR HCC risks were comparable according to treatment regimens; PegIFN- vs. DAA-based regimens and SOF-based vs. SOF-free DAA regimens. Further studies with a longer follow-up period are required.