Targeting Akt in Hepatocellular Carcinoma and Its Tumor Microenvironment

Hypoxia reduces SLC27A5 to promote hepatocellular carcinoma proliferation by repressing HNF4A

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related mortality globally, with hypoxia recognized as a key factor in its progression. Solute carrier family 27 member 5 (SLC27A5/FATP5), a pivotal enzyme in hepatic fatty acid transport and bile acid metabolism, is frequently downregulated in hepatocellular carcinoma, resulting in poor prognosis. However, the link between hypoxia and the suppression of SLC27A5 in HCC remains to be elucidated. Here, we investigated the hypoxia-induced downregulation of SLC27A5 and its impact on HCC proliferation via the repression of hepatocyte nuclear factor 4 alpha (HNF4A). Utilizing in vitro and in vivo hepatocellular carcinoma models, we have demonstrated that hypoxic conditions significantly reduce SLC27A5 transcription, which is mediated by the suppression of HNF4A. This reduction leads to the activation of the AKT pathway and an increase in cyclin-dependent kinase 2 (CDK2) and Cyclin E1 (CCNE1) expression, promoting the transition from the G1 to S phase of the cell cycle and driving HCC proliferation. Furthermore, we show that the pharmacological activation of HNF4A using Benfluorex, in combination with the AKT inhibitor MK2206, significantly inhibits tumor growth in a subcutaneous MHCC-97H xenograft model, suggesting a synergistic therapeutic potential. Together, our study provides novel insights into the hypoxia-mediated regulatory mechanisms in HCC and highlights the HNF4A/SLC27A5/AKT axis as a promising target for combination therapy.

Prediction of Multi-targeting Pharmacological Activity of Bioactive Compounds from Medicinal Plants Against Hepatocellular Carcinoma Through Advanced Network Pharmacology and Bioinformatics-Based Investigation

The primary objective of this study was to identify bioactive compounds from four medicinal plants with multi-targeting activity against hepatocellular carcinoma (HCC). A comprehensive analysis led to the identification of a subset of compounds possessing favorable drug-likeness, pharmacokinetics, and absence of toxicity profiles. Target analysis for 42 phytochemicals revealed 210 potential targets associated with HCC. Protein-protein interaction (PPI) analysis of these targets uncovered five critical hub genes, STAT3, SRC, AKT1, MAPK3, and EGFR, in our study. Correlation analysis of these hub genes indicated a strong positive correlation between EGFR, MAPK3, and SRC expression highlighting their interconnected roles in HCC. Survival analysis underscored the significant prognostic role of these hub genes in HCC underscoring their potential as biomarkers. The co-expression analysis unveiled an intricate network of interactions among the hub genes, while the enrichment analysis demonstrated their enrichment in diverse biological and signaling pathways related to HCC. Molecular docking analysis between the seven phytochemicals and five identified targets revealed that bauerenol exhibited good affinity towards all the targets. Subsequent molecular dynamics (MD) simulations demonstrated that bauerenol formed stable complexes with STAT3, AKT1, EGFR, and MAPK3, suggesting its potential as a multi-targeted inhibitor. Our research suggests that bauerenol shows promise as an inhibitor for HCC targets and stands out as a notable lead compound. However, further experimental studies are necessary to confirm its activity and to evaluate its potential as a therapeutic agent for HCC.

Exploring a novel thiazole derivatives hybrid with fluorinated-indenoquinoxaline as dual inhibitors targeting VEGFR2/AKT and apoptosis inducers against hepatocellular carcinoma with docking simulation

Hepatocellular carcinoma (HCC) ranks as the third most prevalent reason for cancer-related death on a global scale. Tyrosine kinase inhibitors (TKIs) continue to be the primary treatment option for advanced hepatocellular carcinoma. A series of fluoro-11H-indeno[1,2-b]quinoxaline derivatives as an HCC drug targeting the VEGFR2/AKT axis was designed and synthesized. The novel compounds were investigated against HepG-2 and HuH-7 liver tumor cell lines. Compound 5 was the most active derivative against HepG-2 and HuH-7 cell lines with IC50 = 0.75 ± 0.04 and 3.43 ± 0.16 μM, respectively, in contrast to Sorafenib which shows IC50 values of 5.23 ± 0.31 and 4.58 ± 0.21 μM, respectively. IC50 values on normal liver cells (THLE-2) show that all tests are more selective than Sorafenib, prompting further research. The most promising cytotoxic compound has virtually equal VEGFR2 inhibition efficacy to Sorafenib. The total VEGFR2 and p-VEGFR2 inhibitory effects were subsequently evaluated, showing 38.32 % and 77.64 % attenuation, respectively. Compound 5 also reduced total and phosphorylated AKT concentrations in HepG-2 cells by 55.29 % and 78.01 %, respectively. Furthermore, Compound 5 upregulated BAX and caspase-3 and downregulated Bcl-2 to promote apoptosis. Hybrid 5 stops HepG-2's cell cycle at the S phase 48.02 % higher than untreated. Docking experiments assessed AKT and VEGFR2 binding patterns.

The interdisciplinary approach to investigate bona fide agent(s) in flavonoids or alkaloids in treating HCC

Currently, the treatment of hepatocellular carcinoma (HCC) is yet to be determined, alternatively, flavonoids or alkaloids from nature have been considered as significant mediators against HCC. In the scenario, we pioneered the most significant agent(s) in either flavonoid(s) or alkaloid(s) against HCC with cheminformatics, bioinformatics, computer screening tools and quantum chemistry concept. In prospect, the intent was to provide the theoretical scaffold in the myriad natural organic molecules. The cheminformatics (natural product activity & species source database (NPASS), SwissADME, PubChem, Similarity Ensemble Approach (SEA) and SwissTargetPrediction (STP)), bioinformatics (DisGeNET, OMIM and STRING) were employed to underpin promising therapeutic components. The protein-protein interaction (PPI) network to identify the relationships between each target and a bubble chart to elucidate key signalling pathway(s) was constructed via STRING database. Ultimately, computer screening tools (PyMOL and AutoDockTools 1.5.6) and quantum chemistry (GaussView 6 and Gaussian) concept were adopted to decrypt the key molecule(s), target(s) and key mechanism(s). The most significant target was AKT1 in PPI network, AKT1 - isorhamnetin, MCL1 - ochrindole D and PIM1 - heyneanine hydroxyindolenine were the most stable conformers to antagonize JAK-STAT signalling pathway. This study provides scientific manifestation to facilitate the clinical test despite the enormous complexity of herbal medicine, and the devised platform for further clarifying the bioactive(s) and mechanism(s) against HCC.

Ingenane-type diterpenoids inhibit non-small cell lung cancer cells by regulating SRC/PI3K/Akt pathway

Ingenane-type diterpenoids (ITDs) are distinct components of plants belonging to the genus Euphorbia. These compounds have significant cytotoxic effects on non-small cell lung cancer (NSCLC) cells. However, the underlying molecular mechanism has yet to be reported. To explore the mechanism of the anticancer effect of ITDs, we carried out a network pharmacology prediction study. PPI network suggested that SRC and PI3K had high levels of interaction. In addition, KEGG analysis revealed that these common targets were significantly enriched in the PI3K/Akt signalling pathway. 13-oxyingenol-dodecanoate (13OD) was used for validation after the biological evaluation of some ITDs against NSCLC cells. It demonstrated that 13OD could significantly inhibit the growth of NSCLC cells by inducing apoptosis. The results from molecular docking and Western blotting showed that 13OD interacted with SRC and PI3K and down-regulated the SRC/PI3K/Akt signalling pathway in NSCLC cells. This study provided the underlying mechanism of ITDs against NSCLC.

A Novel Affordable and Reliable Framework for Accurate Detection and Comprehensive Analysis of Somatic Mutations in Cancer

Accurate detection and analysis of somatic variants in cancer involve multiple third-party tools with complex dependencies and configurations, leading to laborious, error-prone, and time-consuming data conversions. This approach lacks accuracy, reproducibility, and portability, limiting clinical application. Musta was developed to address these issues as an end-to-end pipeline for detecting, classifying, and interpreting cancer mutations. Musta is based on a Python command-line tool designed to manage tumor-normal samples for precise somatic mutation analysis. The core is a Snakemake-based workflow that covers all key cancer genomics steps, including variant calling, mutational signature deconvolution, variant annotation, driver gene detection, pathway analysis, and tumor heterogeneity estimation. Musta is easy to install on any system via Docker, with a Makefile handling installation, configuration, and execution, allowing for full or partial pipeline runs. Musta has been validated at the CRS4-NGS Core facility and tested on large datasets from The Cancer Genome Atlas and the Beijing Institute of Genomics. Musta has proven robust and flexible for somatic variant analysis in cancer. It is user-friendly, requiring no specialized programming skills, and enables data processing with a single command line. Its reproducibility ensures consistent results across users following the same protocol.

Ultrasound image-guided cancer gene therapy using iRGD dual-targeted magnetic cationic microbubbles

The gene therapy attracted more and more attention for the tumor therapy. To obtain a safe gene therapy system, the new gene vectors beyond the virus were developed for a high gene therapy efficiency. The ultrasound mediated gene therapy was safer and the plasmid DNA could be delivered by the microbubbles and combined with the ultrasound to increase the gene transfection efficiency. In this work, the cationic microbubbles decorated with Cyclo(Cys-Arg-Gly-Asp-Lys-Gly-Pro-AspCys) (iRGD peptides) and magnetic Fe3O4 nanoparticles (MBiM) was designed for targeted ultrasound contrast imaging guided gene therapy of tumors. The ultrasound image intensity was dramatically enhanced at the tumor site that received MBiM with the magnet applied, compared to those administrated the non-targeted microbubbles (MBb) or the microbubbles with only one target material on the surface (MBM and MBbi). The pGPU6/GFP/Neo-shAKT2 was used as a sample gene, which down regulate the AKT2 protein expression for the cancer therapy. It illustrated that MBiM/AKT2 had the highest gene transfection efficiency in the studied microbubbles mediated by the ultrasound, leading to the AKT2 protein expression downregulation and the strongest tumor killing effect in vitro and in vivo. In summary, a novel and biocompatible gene delivery platform via MBiM with both the endogenous and external targeting effects for breast cancer theranostics was developed.

Hijacking and rewiring of host CircRNA/miRNA/mRNA competitive endogenous RNA (ceRNA) regulatory networks by oncoviruses during development of viral cancers

A significant portion of human cancers are caused by oncoviruses (12%-25%). Oncoviruses employ various strategies to promote their replication and induce tumourigenesis in host cells, one of which involves modifying the gene expression patterns of the host cells, leading to the rewiring of genes and resulting in significant changes in cellular processes and signalling pathways. In recent studies, a specific mode of gene regulation known as circular RNA (circRNA)-mediated competing endogenous RNA (ceRNA) networks has emerged as a key player in this context. CircRNAs, a class of non-coding RNA molecules, can interact with other RNA molecules, such as mRNAs and microRNAs (miRNAs), through a process known as ceRNA crosstalk. This interaction occurs when circRNAs, acting as sponges, sequester miRNAs, thereby preventing them from binding to their target mRNAs and modulating their expression. By rewiring the host cell genome, oncoviruses have the ability to manipulate the expression and activity of circRNAs, thereby influencing the ceRNA networks that can profoundly impact cellular processes such as cell proliferation, differentiation, apoptosis, and immune responses. This review focuses on a comprehensive evaluation of the latest findings on the involvement of virus-induced reprogramming of host circRNA-mediated ceRNA networks in the development and pathophysiology of human viral cancers, including cervical cancer, gastric cancer, nasopharyngeal carcinoma, Kaposi's sarcoma, hepatocellular carcinoma, and diffuse large B cell lymphoma. Understanding these mechanisms can improve our knowledge of how oncoviruses contribute to human tumourigenesis and identify potential targets for developing optimised therapies and diagnostic tools for viral cancers.

The transcription factor ChREBP Orchestrates liver carcinogenesis by coordinating the PI3K/AKT signaling and cancer metabolism

Cancer cells integrate multiple biosynthetic demands to drive unrestricted proliferation. How these cellular processes crosstalk to fuel cancer cell growth is still not fully understood. Here, we uncover the mechanisms by which the transcription factor Carbohydrate responsive element binding protein (ChREBP) functions as an oncogene during hepatocellular carcinoma (HCC) development. Mechanistically, ChREBP triggers the expression of the PI3K regulatory subunit p85α, to sustain the activity of the pro-oncogenic PI3K/AKT signaling pathway in HCC. In parallel, increased ChREBP activity reroutes glucose and glutamine metabolic fluxes into fatty acid and nucleic acid synthesis to support PI3K/AKT-mediated HCC growth. Thus, HCC cells have a ChREBP-driven circuitry that ensures balanced coordination between PI3K/AKT signaling and appropriate cell anabolism to support HCC development. Finally, pharmacological inhibition of ChREBP by SBI-993 significantly suppresses in vivo HCC tumor growth. Overall, we show that targeting ChREBP with specific inhibitors provides an attractive therapeutic window for HCC treatment.

Co-overexpression of BRD4 and CDK7 promotes cell proliferation and predicts poor prognosis in HCC

Aberrant expression of critical components of the trans-acting super-enhancers (SE) complex contributes to the continuous and robust transcription of oncogenes in human cancers. Small-molecule inhibitors targeting core-transcriptional components such as transcriptional bromodomain protein 4 (BRD4) and cyclin-dependent kinase 7 (CDK7) have been developed and are currently undergoing preclinical and clinical testing in several malignant cancers. By analysis of TCGA data and clinical specimens, we demonstrated that BRD4 and CDK7 were frequently overexpressed in human HCCs and were associated with the poor prognosis. Shorter survival and poorly differentiated histology were linked to high BRD4 or CDK7 expression levels. Interestingly, co-overexpression of BRD4 and CDK7 was a more unfavorable prognostic factor in HCC. Treatment with JQ1 or THZ1 alone exhibited an inhibitory impact on the proliferation of HCC cells, while JQ1 synergized with THZ1 showed a more pronounced suppression. Concurrently, a combined JQ1 and THZ1 treatment abolished the transcription of oncogenes ETV4, MYC, NFE2L2. Our study suggested that BRD4 and CDK7 coupled can be a valuable biomarker in HCC diagnosis and the combination of JQ1 and THZ1 can be a promising therapeutic treatment against HCC.

Copine 1 predicts poor clinical outcomes by promoting M2 macrophage activation in ovarian cancer

OBJECTIVE

Copine 1 (CPNE1), a membrane-binding protein, influences the prognosis of various cancers. According to cBioPortal, CPNE1 amplification is a prevalent genetic mutation in ovarian cancer but with unknown oncogenic mechanism.

METHODS

This study analysed the CPNE1 expression in ovarian cancer using online datasets, as validated by immunohistochemistry (IHC), quantitative polymerase chain reaction (qPCR) and western blotting. Concurrently, the prognostic value of CPNE1 was accessed. Cell Counting Kit-8, colony formation, transwells and xenograft experiments were performed to evaluate the functions of CPNE1 during ovarian cancer carcinogenesis. CPNE1 and its related genes were analysed by g:Profiler and Tumour Immune Estimation Resource. Furthermore, human monocytic THP-1 cells were co-cultured with ES2 cells to investigate the effect of CPNE1 on macrophage polarization.

RESULTS

The results of bioinformatic analysis, IHC, qPCR and western blotting indicated a higher CPNE1 in ovarian cancer. CPNE1 overexpression demonstrated an association with a poor prognosis of ovarian cancer. Functionally, CPNE1 overexpression increased ES2 and SKOV3 cell proliferation, invasion and migration in vitro and promoted ovarian tumour xenograft growth in vivo, while CPNE1 knockdown led to opposite effects. Additionally, CPNE1 expression demonstrated an association with immune cell infiltration in ovarian cancer, especially macrophage. CPNE1 promoted protumour M2 macrophage polarization by upregulating cluster of differentiation 163 (CD163), CD206 and interleukin-10.

CONCLUSIONS

Our study revealed that CPNE1 mediated M2 macrophage polarization and provided a therapeutic target for ovarian cancer.

Cryptocaryone induces apoptosis in human hepatocellular carcinoma cells by inhibiting aerobic glycolysis through Akt and c-Src signaling pathways

Hepatocellular carcinoma (HCC) is the most common form of liver cancer, with the second highest mortality rate in all cancer. Energy reprogramming is one of the hallmarks of cancer, and emerging evidence showed that targeting glycolysis is a promising strategy for HCC treatment. Cryptocaryone has been shown to display promising anti-cancer activity against numerous types of cancer. Previous study also indicated that cryptocaryone induces cytotoxicity by inhibiting glucose transport in cancer cells, but the detailed mechanism still needs to be elucidated. Therefore, this study aimed to investigate the relationship between the anti-cancer effect and glycolytic metabolism of cryptocaryone in human HCC cells. In this study, we found that cryptocaryone potently induced growth inhibition by apoptotic cell death in HCC cells. Cryptocaryone also suppressed the ATP synthesis, lactate production and glycolytic capacity of HCC cells. Mechanistic investigations showed that phosphorylation of Akt and c-Src, as well as the expression of HK1 were impeded by cryptocaryone. Moreover, cryptocaryone markedly increased the expression level of transcription factor FoxO1. Importantly, clinical database analysis confirmed the negative correlation between HK1 and FoxO1. High expression levels of HK-1 were positively correlated with poorer survival in patients with HCCs. These results suggest that cryptocaryone may promote cell apoptosis by inhibiting FoxO1-mediated aerobic glycolysis through Akt and c-Src signaling cascades in human HCC cells. This is the first study to indicate that cryptocaryone exerts anti-cancer property against human HCC cells. Cryptocaryone is a potential natural product worthy of further development into a promising candidate for HCC treatment.

Anticancer perspective of 6-shogaol: anticancer properties, mechanism of action, synergism and delivery system

Cancer is a malignant disease that has plagued human beings all the time, but the treatment effect of commonly used anticancer drugs in clinical practice is not ideal by reason of their drug tolerance and Strong adverse reactions to patients. Therefore, it is imperative to find effective and low-toxic anticancer drugs. Many research works have shown that natural products in Chinese herbal medicine have great anticancer potential, such as 6-shogaol, a monomer composition obtained from Chinese herbal ginger, which has been confirmed by numerous in vitro or vivo studies to be an excellent anti-cancer active substance. In addition, most notably, 6-shogaol has different selectivity for normal and cancer cells during treatment, which makes it valuable for further research and clinical development. Therefore, this review focus on the anti-cancer attributes, the mechanism and the regulation of related signaling pathways of 6-shogaol. In addition, its synergy with commonly used anticancer drugs, potential drug delivery systems and prospects for future research are discussed. This is the first review to comprehensively summarize the anti-cancer mechanism of 6-shogaol, hoping to provide a theoretical basis and guiding significance for future anti-cancer research and clinical development of 6-shogaol.

Biomarker Discovery for Hepatocellular Carcinoma in Patients with Liver Cirrhosis Using Untargeted Metabolomics and Lipidomics Studies

Hepatocellular carcinoma (HCC), the most prevalent form of liver cancer, is the third leading cause of mortality globally. Patients with HCC have a poor prognosis due to the fact that the emergence of symptoms typically occurs at a late stage of the disease. In addition, conventional biomarkers perform suboptimally when identifying HCC in its early stages, heightening the need for the identification of new and more effective biomarkers. Using metabolomics and lipidomics approaches, this study aims to identify serum biomarkers for identification of HCC in patients with liver cirrhosis (LC). Serum samples from 20 HCC cases and 20 patients with LC were analyzed using ultra-high-performance liquid chromatography-Q Exactive mass spectrometry (UHPLC-Q-Exactive-MS). Metabolites and lipids that are significantly altered between HCC cases and patients with LC were identified. These include organic acids, amino acids, TCA cycle intermediates, fatty acids, bile acids, glycerophospholipids, sphingolipids, and glycerolipids. The most significant variability was observed in the concentrations of bile acids, fatty acids, and glycerophospholipids. In the context of HCC cases, there was a notable increase in the levels of phosphatidylethanolamine and triglycerides, but the levels of fatty acids and phosphatidylcholine exhibited a substantial decrease. In addition, it was observed that all of the identified metabolites exhibited a superior area under the receiver operating characteristic (ROC) curve in comparison to alpha-fetoprotein (AFP). The pathway analysis of these metabolites revealed fatty acid, lipid, and energy metabolism as the most impacted pathways. Putative biomarkers identified in this study will be validated in future studies via targeted quantification.

Loss of hepatic FTCD promotes lipid accumulation and hepatocarcinogenesis by upregulating PPARγ and SREBP2

Background & Aims

Exploiting key regulators responsible for hepatocarcinogenesis is of great importance for the prevention and treatment of hepatocellular carcinoma (HCC). However, the key players contributing to hepatocarcinogenesis remain poorly understood. We explored the molecular mechanisms underlying the carcinogenesis and progression of HCC for the development of potential new therapeutic targets.

Methods

The Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) and Genotype-Tissue Expression (GTEx) databases were used to identify genes with enhanced expression in the liver associated with HCC progression. A murine liver-specific Ftcd knockout (Ftcd-LKO) model was generated to investigate the role of formimidoyltransferase cyclodeaminase (FTCD) in HCC. Multi-omics analysis of transcriptomics, metabolomics, and proteomics data were applied to further analyse the molecular effects of FTCD expression on hepatocarcinogenesis. Functional and biochemical studies were performed to determine the significance of loss of FTCD expression and the therapeutic potential of Akt inhibitors in FTCD-deficient cancer cells.

Results

FTCD is highly expressed in the liver but significantly downregulated in HCC. Patients with HCC and low levels of FTCD exhibited worse prognosis, and patients with liver cirrhosis and low FTCD levels exhibited a notable higher probability of developing HCC. Hepatocyte-specific knockout of FTCD promoted both chronic diethylnitrosamine-induced and spontaneous hepatocarcinogenesis in mice. Multi-omics analysis showed that loss of FTCD affected fatty acid and cholesterol metabolism in hepatocarcinogenesis. Mechanistically, loss of FTCD upregulated peroxisome proliferator-activated receptor (PPAR)γ and sterol regulatory element-binding protein 2 (SREBP2) by regulating the PTEN/Akt/mTOR signalling axis, leading to lipid accumulation and hepatocarcinogenesis.

Conclusions

Taken together, we identified a FTCD-regulated lipid metabolic mechanism involving PPARγ and SREBP2 signaling in hepatocarcinogenesis and provide a rationale for therapeutically targeting of HCC driven by downregulation of FTCD.

Impact and implications

Exploiting key molecules responsible for hepatocarcinogenesis is significant for the prevention and treatment of HCC. Herein, we identified formimidoyltransferase cyclodeaminase (FTCD) as the top enhanced gene, which could serve as a predictive and prognostic marker for patients with HCC. We generated and characterised the first Ftcd liver-specific knockout murine model. We found loss of FTCD expression upregulated peroxisome proliferator-activated receptor (PPAR)γ and sterol regulatory element-binding protein 2 (SREBP2) by regulating the PTEN/Akt/mTOR signalling axis, leading to lipid accumulation and hepatocarcinogenesis, and provided a rationale for therapeutic targeting of HCC driven by downregulation of FTCD.

Cannabis sativa demonstrates anti-hepatocellular carcinoma potentials in animal model: in silico and in vivo studies of the involvement of Akt

BACKGROUND

Targeting protein kinase B (Akt) and its downstream signaling proteins are promising options in designing novel and potent drug candidates against hepatocellular carcinoma (HCC). The present study explores the anti-HCC potentials of Cannabis sativa (C. sativa) extract via the involvement of Akt using both in silico and in vivo animal models of HCC approaches.

METHODS

Phytoconstituents of C. sativa extract obtained from Gas Chromatography Mass-spectrometry (GCSM) were docked into the catalytic domain of Akt-2. The Diethylnitrosamine (DEN) model of HCC was treated with C. sativa extract. The effects of C. sativa extract treatments on DEN model of hepatocellular carcinoma were assessed by One-way analysis of variance (ANOVA) of the treated and untreated groups RESULT: The lead phytoconstituents of C. sativa extract, Δ-9-tetrahydrocannabinol (Δ-9-THC) and cannabidiol form stable hydrophobic and hydrogen bond interactions within the catalytic domain of Akt-2. C. sativa extract (15 mg/kg and 30 mg/kg) respectively gives a 3-fold decrease in the activities of liver function enzymes when compared with the positive control (group 2). It also gives a 1.5-fold decrease in hepatic lipid peroxidation and elevates serum antioxidant enzymes' activities by 1-fold in HCC treated Wistar rats when compared with the positive control (group 2). In an animal model of hepatocellular carcinoma, C. sativa extract significantly downregulated Akt and HIF mRNAs in groups 3, 4, and 5 with 2, 1.5, 2.5-fold decrease relative to group 2. VEGF mRNA was downregulated by 1.5-fold decrease in groups 3-5 when compared to group 2. The expression of XIAP mRNA was downregulated by 1.5, 2, and 1.25-folds in groups 3, 4, and 5 respectively, in comparison with group 2. In comparison to group 2, COX-2 mRNA levels were downregulated by 1.5, 1, and 1-folds in groups 3-5. In groups 3-5, CRP mRNA was downregulated by 2-fold in comparison with group 2. In groups 3-5, p21 mRNA was upregulated by 2, 2.5, and 3-folds, respectively when compared with group 2. It upregulated p53 mRNA by 2.5, 3.5, and 2.5-folds in groups 3-5 in comparison with group 2. It downregulated AFP mRNA by 3.5, 2.5, .2.5-folds in groups 3, 4, and 5 respectively when compared with group 2. Histologic analysis showed that C. sativa extract reduced necrosis and inflammation in HCC.

CONCLUSION

C. sativa demonstrates anti-hepatocellular carcinoma potentials in an animal model of HCC and with the involvement of Akt. Its anticancer potential is mediated through antiangiogenic, proapoptotic, cycle arrest, and anti-inflammatory mechanisms. In future studies, the mechanisms of anti-HCC effects of Δ-9-tetrahydrocannabinol (Δ-9- THC) and cannabidiol via the PI3K-Akt signaling pathways should be explored.

Discovering Deleterious Single Nucleotide Polymorphisms of Human AKT1 Oncogene: An In Silico Study

BACKGROUND

AKT1 is a serine/threonine kinase necessary for the mediation of apoptosis, angiogenesis, metabolism, and cell proliferation in both normal and cancerous cells. The mutations in the AKT1 gene have been associated with different types of cancer. Further, the AKT1 gene mutations are also reported to be associated with other diseases such as Proteus syndrome and Cowden syndromes. Hence, this study aims to identify the deleterious AKT1 missense SNPs and predict their effect on the function and structure of the AKT1 protein using various computational tools.

METHODS

Extensive in silico approaches were applied to identify deleterious SNPs of the human AKT1 gene and assessment of their impact on the function and structure of the AKT1 protein. The association of these highly deleterious missense SNPs with different forms of cancers was also analyzed. The in silico approach can help in reducing the cost and time required to identify SNPs associated with diseases.

RESULTS

In this study, 12 highly deleterious SNPs were identified which could affect the structure and function of the AKT1 protein. Out of the 12, four SNPs-namely, G157R, G159V, G336D, and H265Y-were predicted to be located at highly conserved residues. G157R could affect the ligand binding to the AKT1 protein. Another highly deleterious SNP, R273Q, was predicted to be associated with liver cancer.

CONCLUSIONS

This study can be useful for pharmacogenomics, molecular diagnosis of diseases, and developing inhibitors of the AKT1 oncogene.

Porphyromonas gingivalis-odontogenic infection is the potential risk for progression of nonalcoholic steatohepatitis-related neoplastic nodule formation

Porphyromonas gingivalis (P.g.), a major periodontal pathogen is a known risk factor for various systemic diseases. However, the relationship between P.g. and nonalcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC) is unclear. Thus, we aimed to elucidate whether P.g.-odontogenic infection promotes NASH-related HCC development/progression and to clarify its mechanism. Using high-fat diet (HFD)-induced NASH mouse model, P.g. was infected odontogenically. After 60 weeks of infection, tumor profiles were examined. Chow diet (CD) groups were also prepared at 60 weeks. Nodule formation was only seen in HFD-mice. P.g.-odontogenic infection significantly increased the mean nodule area (P = 0.0188) and tended to promote histological progression score after 60 weeks (P = 0.0956). Interestingly, P.g. was detected in the liver. HFD-P.g. (+) showed numerous TNF-α positive hepatic crown-like structures and 8-OHdG expression in the non-neoplastic liver. In P.g.-infected hepatocytes, phosphorylation of integrin β1 signaling molecules (FAK/ERK/AKT) was upregulated in vitro. In fact, total AKT in the liver of HFD-P.g. (+) was higher than that of HFD-P.g. (-). P.g.-infected hepatocytes showed increased cell proliferation and migration, and decreased doxorubicin-mediated apoptosis. Integrin β1 knockdown inhibited these phenotypic changes. P.g.-odontogenic infection may promote the progression of neoplastic nodule formation in an HFD-induced NASH mouse model via integrin signaling and TNF-α induced oxidative DNA damage.

Effect of Novel AKT Inhibitor Vevorisertib as Single Agent and in Combination with Sorafenib on Hepatocellular Carcinoma in a Cirrhotic Rat Model

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide. The AKT pathway is often activated in HCC cases, and a longer exposure to tyrosine kinase inhibitors such as sorafenib may lead to over-activation of the AKT pathway, leading to HCC resistance. Here, we studied the efficacy of a new generation of allosteric AKT inhibitor, vevorisertib, alone or in combination with sorafenib. To identify specific adverse effects related to the background of cirrhosis, we used a diethylnitrosamine (DEN)-induced cirrhotic rat model. Vevorisertib was tested in vitro on Hep3B, HepG2, HuH7 and PLC/PRF cell lines. Rats were treated weekly with intra-peritoneal injections of DEN for 14 weeks to obtain cirrhosis with fully developed HCC. After that, rats were randomized into four groups (n = 7/group): control, sorafenib, vevorisertib and the combination of vevorisertib + sorafenib, and treated for 6 weeks. Tumor progression was followed by MRI. We demonstrated that the vevorisertib is a highly potent treatment, blocking the phosphorylation of AKT. The tumor progression in the rat liver was significantly reduced by treatment with vevorisertib + sorafenib (49.4%) compared to the control group (158.8%, p < 0.0001). Tumor size, tumor number and tumor cell proliferation were significantly reduced in both the vevorisertib group and vevorisertib + sorafenib groups compared to the control group. Sirius red staining showed an improvement in liver fibrosis by vevorisertib and the combination treatment. Moreover, vevorisertib + sorafenib treatment was associated with a normalization in the liver vasculature. Altogether, vevorisertib as a single agent and its combination with sorafenib exerted a strong suppression of tumor progression and improved liver fibrosis. Thus, results provide a rationale for testing vevorisertib in clinical settings and confirm the importance of targeting AKT in HCC.

The Double Face of miR-708: A Pan-Cancer Player with Dissociative Identity Disorder

Over the last decades, accumulating evidence has shown tumor-dependent profiles of miR-708, being either up- or downregulated, and thus, acting as a "Janus" regulator of oncogenic pathways. Herein, its functional duality was assessed through a thorough review of the literature and further validation in silico using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. In the literature, miR-708 was found with an oncogenic role in eight tumor types, while a suppressor tumor role was described in seven cancers. This double profile was also found in TCGA and GEO databases, with some tumor types having a high expression of miR-708 and others with low expression compared with non-tumor counterparts. The investigation of validated targets using miRBase, miRTarBase, and miRecords platforms, identified a total of 572 genes that appeared enriched for PI3K-Akt signaling, followed by cell cycle control, p53, Apellin and Hippo signaling, endocrine resistance, focal adhesion, and cell senescence regulations, which are all recognized contributors of tumoral phenotypes. Among these targets, a set of 15 genes shared by at least two platforms was identified, most of which have important roles in cancer cells that influence either tumor suppression or progression. In a clinical scenario, miR-708 has shown to be a good diagnostic and prognosis marker. However, its multitarget nature and opposing roles in diverse human tumors, aligned with insufficient experimental data and the lack of proper delivery strategies, hamper its potential as a sequence-directed therapeutic.

Zinc fingers and homeoboxes 2 is required for diethylnitrosamine-induced liver tumor formation in C57BL/6 mice

Liver cancer, comprised primarily of hepatocellular carcinoma (HCC), is the third leading cause of cancer deaths worldwide and increasing in Western countries. We previously identified the transcription factor zinc fingers and homeoboxes 2 (Zhx2) as a regulator of hepatic gene expression, and many Zhx2 target genes are dysregulated in HCC. Here, we investigate HCC in Zhx2-deficient mice using the diethylnitrosamine (DEN)-induced liver tumor model. Our study using whole-body Zhx2 knockout (Zhx2KO ) mice revealed the complete absence of liver tumors 9 and 10 months after DEN exposure. Analysis soon after DEN treatment showed no differences in expression of the DEN bioactivating enzyme cytochrome P450 2E1 (CYP2E1) and DNA polymerase delta 2, or in the numbers of phosphorylated histone variant H2AX foci between Zhx2KO and wild-type (Zhx2wt ) mice. The absence of Zhx2, therefore, did not alter DEN bioactivation or DNA damage. Zhx2KO livers showed fewer positive foci for Ki67 staining and reduced interleukin-6 and AKT serine/threonine kinase 2 expression compared with Zhx2wt livers, suggesting that Zhx2 loss reduces liver cell proliferation and may account for reduced tumor formation. Tumors were reduced but not absent in DEN-treated liver-specific Zhx2 knockout mice, suggesting that Zhx2 acts in both hepatocytes and nonparenchymal cells to inhibit tumor formation. Analysis of data from the Cancer Genome Atlas and Clinical Proteomic Tumor Consortium indicated that ZHX2 messenger RNA and protein levels were significantly higher in patients with HCC and associated with clinical pathological parameters. Conclusion: In contrast to previous studies in human hepatoma cell lines and other HCC mouse models showing that Zhx2 acts as a tumor suppressor, our data indicate that Zhx2 acts as an oncogene in the DEN-induced HCC model and is consistent with the higher ZHX2 expression in patients with HCC.

Patient-specific and gene-corrected induced pluripotent stem cell-derived endothelial cells elucidate single-cell phenotype of pulmonary veno-occlusive disease

Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension characterized by the preferential remodeling of the pulmonary venules. Hereditary PVOD is caused by biallelic variants of the EIF2AK4 gene. Three PVOD patients who carried the compound heterozygous variants of EIF2AK4 and two healthy controls were recruited and induced pluripotent stem cells (iPSCs) were generated from human peripheral blood mononuclear cells (PBMCs). The EIF2AK4 c.2965C>T variant (PVOD#1), c.3460A>T variant (PVOD#2), and c.4832_4833insAAAG variant (PVOD#3) were corrected by CRISPR-Cas9 in PVOD-iPSCs to generate isogenic controls and gene-corrected-iPSCs (GC-iPSCs). PVOD-iPSC-endothelial cells (ECs) exhibited a decrease in GCN2 protein and mRNA expression when compared with control and GC-ECs. PVOD-ECs exhibited an abnormal EC phenotype featured by excessive proliferation and angiogenesis. The abnormal phenotype of PVOD-ECs was normalized by protein kinase B inhibitors AZD5363 and MK2206. These findings help elucidate the underlying molecular mechanism of PVOD in humans and to identify promising therapeutic drugs for treating the disease.

Systems Network Pharmacology-Based Prediction and Analysis of Potential Targets and Pharmacological Mechanism of Actinidia chinensis Planch. Root Extract for Application in Hepatocellular Carcinoma

Purpose

Traditional Chinese medicine (TCM) sometimes plays a crucial role in advanced cancer treatment. Despite the significant therapeutic efficacy in hepatocellular carcinoma (HCC) that Actinidia chinensis Planch root extract (acRoots) has proven, its complex composition and underlying mechanism have not been fully elucidated. Therefore, this study analyzed the multiple chemical compounds in acRoots and their targets via network pharmacology and bioinformatics analysis, with the overarching goal of revealing the potential mechanisms of the anti-HCC effect.

Methods

The main ingredients contained in acRoots were initially screened from the traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), and the candidate bioactive ingredient targets were identified using DrugBank and the UniProt public databases. Second, the biological processes of the targets of active molecules filtered from the ingredients of acRoots were evaluated using gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Third, weighted gene coexpression network analysis (WGCNA) was performed to identify gene coexpression modules associated with HCC. The hub genes of acRoots in HCC were defined via contrasting the above module eigengenes with candidate target genes of acRoots. Furthermore, the target-pathway network was analyzed to explore the mechanism for anti-HCC effect of hub genes. Kaplan–Meier plotter database analysis was performed to validate the hub genes of acRoots correlation with prognostic values in HCC. In order to verify the results of the network pharmacological analysis, we performed a molecular docking approach on the active ingredients and key targets using the Discovery Studio software. The viability of SMMC-7721 and HL-7702 cells was determined by Cell counting kit-8 (CCK-8) after being treated with different concentrations of (+)-catechin (0, 50, 100, 150, 200, and 250 g/ml) for 24, 48, and 72 hours, respectively. Finally, qRT-PCR and Western blot involving human hepatocarcinoma cells were utilized to verify the impact of (+)-catechin on the hub genes associated with prognosis.

Results

6 out of 26 active ingredients extracted from TCMSP were deemed as the core ingredients of acRoots. 175 bioactive-ingredient targets of acRoots were obtained and a bioactive-ingredient targets network was established correspondingly. The biological processes (BP) of target genes mainly involved processes, such as toxic substance and wounding. The results of KEGG pathways indicated that the target genes were mainly enriched in pathways in cancer, AGE-RAGE signaling pathway in diabetic complications, IL-17 signaling pathway, and other pathways. Also, the two hub genes (i.e., ESR1 and CAT) were closely associated with the prognosis of HCC patients. As a consequence, we predicated a series of signaling pathways, including estrogen signaling pathway and longevity regulation pathway, through which acRoots could facilitate the treatment for HCC. The molecular docking experiment ascertained that ESR1 and CAT had an effective binding force with (+)-catechin, one of the core ingredients of acRoots. Furthermore, (+)-catechin inhibited SMMC-7721 cell growth in a dose-dependent manner and a time-dependent manner. Finally, we suggest that the expression level of ESR1 and CAT is positively related to the (+)-catechin concentrations in in-vitro experiments.

Conclusion

The bioactive ingredients of acRoots, including quercetin, (+)-catechin, beta-sitosterol, and aloe-emodin, have synergistic interactions in reinforcing the anticancer effect in HCC. Evidently, acRoots took effect by regulating multitargets and multipathways through its active ingredients. Further, (+)-catechin, the possible paramount anti-HCC active ingredient in acRoots, helped improve the prognosis of HCC patients by increasing the expression of ESR1 and CAT. Additionally, the findings yielded provide a conceptual guidance for the clinical treatment of HCC and the methods adopted are potentially applicable in the future comprehensive analysis of the underlying mechanisms of TCMs.

Circular RNA hsa_circ_0062682 Binds to YBX1 and Promotes Oncogenesis in Hepatocellular Carcinoma

Circular RNAs (circRNAs) have been shown to play an important role in the pathogenesis of hepatocellular carcinoma (HCC). By implementing available transcriptomic analyses of HCC patients, we identified an upregulated circRNA hsa_circ_0062682. Stable perturbations of hsa_circ_0062682 in Huh-7 and SNU-449 cell lines influenced colony formation, migration, cell proliferation, sorafenib sensitivity, and additionally induced morphological changes in cell lines, indicating an important role of hsa_circ_0062682 in oncogenesis. Pathway enrichment analysis and gene set enrichment analysis of the transcriptome data from hsa_circ_0062682 knockdown explained the observed phenotypes and exposed transcription factors E2F1, Sp1, HIF-1α, and NFκB1 as potential downstream targets. Biotinylated oligonucleotide pulldown combined with proteomic analyses identified protein interaction partners of which YBX1, a known oncogene, was confirmed by RNA immunoprecipitation. Furthermore, we discovered a complex cell-type-specific phenotype in response to the oncogenic potential of hsa_circ_0062682. This finding is in line with different classes of HCC tumours, and more studies are needed to shed a light on the molecular complexity of liver cancer.

Network pharmacology-based study on apigenin present in the methanolic fraction of leaves extract of Cestrum nocturnum L. to uncover mechanism of action on hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common type of cancer in the world. It is the third leading cause of cancer-related mortality. In more than 80% of people liver cancer-related death is due to its poor prognosis. The flavonoids obtained from natural sources have potent therapeutic effects on HCC. The flavonoid rich methanolic fraction obtained from ethyl acetate extract of leaf of Cestrum nocturnum (MFLCN) was analyzed by UPLC-QTOFMS/MS for the presence of different flavonoids. The physiochemical and pharmacokinetics properties of the identified flavonoids were performed by absorption, distribution, metabolism, excretion, and toxicity (ADMET). It was selected on the basis of Lipinski rule and hepatotoxicity evaluations. The potential gene dataset of HCC were taken from gene card database and targets compounds were selected from target net prediction. Gene ontology and pathway enrichment analysis of HCC was performed via enricher and David web tools. Cytoscape was used to visualize targets and network pathways. MFLCN contains 33 flavonoids. Among these flavonoids, apigenin was selected as principal active compound on the basis of their pharmacokinetic and ADMET properties. Apigenin has 92 targets out of 627 total targets related to HCC, while there was13 pathways in the target-pathway network. Results revealed that apigenin regulates cell proliferation and survival, primarily through different signaling pathways like estrogen, VEGF, PI3K/AKT1, TNF, FoXO, and Ras signaling pathways. Thus, integrating network pharmacology prediction with m-RNA and human protein atlas validation could be an effective method for understanding the molecular mechanism of apigenin on HCC.

Impacts of Oxidative Stress and PI3K/AKT/mTOR on Metabolism and the Future Direction of Investigating Fucoidan-Modulated Metabolism

The critical factors for regulating cancer metabolism are oxidative stress and phosphoinositide-3-kinase/AKT serine-threonine kinase/mechanistic target of the rapamycin kinase (PI3K/AKT/mTOR). However, the metabolic impacts of oxidative stress and PI3K/AKT/mTOR on individual mechanisms such as glycolysis (Warburg effect), pentose phosphate pathway (PPP), fatty acid synthesis, tricarboxylic acid cycle (TCA) cycle, glutaminolysis, and oxidative phosphorylation (OXPHOS) are complicated. Therefore, this review summarizes the individual and interacting functions of oxidative stress and PI3K/AKT/mTOR on metabolism. Moreover, natural products providing oxidative stress and PI3K/AKT/mTOR modulating effects have anticancer potential. Using the example of brown algae-derived fucoidan, the roles of oxidative stress and PI3K/AKT/mTOR were summarized, although their potential functions within diverse metabolisms were rarely investigated. We propose a potential application that fucoidan may regulate oxidative stress and PI3K/AKT/mTOR signaling to modulate their associated metabolic regulations. This review sheds light on understanding the impacts of oxidative stress and PI3K/AKT/mTOR on metabolism and the future direction of metabolism-based cancer therapy of fucoidan.

The Research Progress of Bufalin in the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the deadliest cancers in the world with a five-year survival rate of less than 20%. Nonetheless, selecting an appropriate therapeutic agent to inhibit the development of hepatoma cells is still a challenge. Bufalin, a component of the traditional Chinese medicine Chansu, has been shown to inhibit the proliferation, invasion and metastasis of HCC through various signaling pathways. In addition, bufalin and sorafenib demonstrate a synergistic effect in cancer therapeutics. This review highlighted on several focal signaling pathways involved in the inhibitory effects of bufalin on HCC and its synergistic mechanisms with sorafenib. The immunotherapy effect of bufalin has also been discussed as a novel property.

Non-coding RNA-associated competitive endogenous RNA regulatory networks: Novel diagnostic and therapeutic opportunities for hepatocellular carcinoma

Hepatocellular carcinoma (HCC), as the most prevalent liver malignancy, is annually diagnosed in more than half a million people worldwide. HCC is strongly associated with hepatitis B and C viral infections as well as alcohol abuse. Obesity and nonalcoholic fatty liver disease (NAFLD) also significantly enhance the risk of liver cancer. Despite recent improvements in therapeutic approaches, patients diagnosed in advanced stages show poor prognosis. Accumulating evidence provides support for the regulatory role of non-coding RNAs (ncRNAs) in cancer. There are a variety of reports indicating the regulatory role of microRNAs (miRNAs) in different stages of HCC. Long non-coding RNAs (LncRNAs) exert their effects by sponging miRNAs and controlling the expression of miRNA-targeted genes. Circular RNAs (circRNAs) perform their biological functions by acting as transcriptional regulators, miRNA sponges and protein templates. Diverse studies have illustrated that dysregulation of competing endogenous RNA networks (ceRNETs) is remarkably correlated with HCC-causing diseases such as chronic viral infections, nonalcoholic steatohepatitis and liver fibrosis/cirrhosis. The aim of the current article was to provide an overview of the role and molecular mechanisms underlying the function of ceRNETs that modulate the characteristics of HCC such as uncontrolled cell proliferation, resistance to cell death, metabolic reprogramming, immune escape, angiogenesis and metastasis. The current knowledge highlights the potential of these regulatory RNA molecules as novel diagnostic biomarkers and therapeutic targets in HCC.

Persistent mTORC1 activation via Depdc5 deletion results in spontaneous hepatocellular carcinoma but does not exacerbate carcinogen- and high-fat diet-induced hepatic carcinogenesis in mice

The mechanistic target of rapamycin complex 1 (mTORC1) acts as a central regulator of metabolic pathways that drive cellular growth. Abnormal activation of mTORC1 occurs at high frequency in human and mouse hepatocellular carcinoma (HCC). DEP domain-containing protein 5 (DEPDC5), a component of GATOR1 complex, is a repressor of amino acid-sensing branch of the mTORC1 pathway. In the current study, we found that persistent activation of hepatic mTORC1 signaling caused by Depdc5 ablation was sufficient to induce a pathological program of liver damage, inflammation and fibrosis that triggers spontaneous HCC development. Take advantage of the combinatory treatment with a single dose of diethylnitrosamine (DEN) and chronic feeding with high-fat diet (HFD), we demonstrated that hepatic depdc5 deletion did not aggravate DEN&HFD induced liver tumorigenesis, probably due to its protective effects on diet-induced liver steatosis. In addition, we further showed that chronic rapamycin treatment did not have any apparent tumor-suppressing effects on DEN&HFD treated control mice, whereas it dramatically reduced the tumor burden in mice with hepatic Depdc5 ablation. This study provides the novel in vivo evidence for Depdc5 deletion mediated mTORC1 hyperactivation in liver tumorigenesis caused by aging or DEN&HFD treatment. Moreover, our findings also propose that pharmacological inhibition of mTORC1 signaling maybe a promising strategy to treat HCC patients with mutations in DEPDC5 gene.

Synthetic Tryptanthrin Derivatives Induce Cell Cycle Arrest and Apoptosis via Akt and MAPKs in Human Hepatocellular Carcinoma Cells

Trytanthrin, found in Ban-Lan-Gen, is a natural product containing an indoloquinazoline moiety and has been shown to possess anti-inflammatory and anti-viral activities. Chronic inflammation and hepatitis B are known to be associated with the progression of hepatocellular carcinoma (HCC). In this study, a series of tryptanthrin derivatives were synthesized to generate potent anti-tumor agents against HCC. This effort yielded two compounds, A1 and A6, that exhibited multi-fold higher cytotoxicity in HCC cells than the parent compound. Flow cytometric analysis demonstrated that A1 and A6 caused S-phase arrest and downregulated the expression of cyclin A1, B1, CDK2, and p-CDC2. In addition to inducing caspase-dependent apoptosis, A1 and A6 exhibited similar regulation of the phosphorylation or expression of multiple signaling targets, including Akt, NF-κB, and mitogen-activated protein kinases. The anti-tumor activities of A1 and A6 were also attributable to the generation of reactive oxygen species, accompanied by an increase in p-p53 levels. Therefore, A1 and A6 have potential clinical applications since they target diverse aspects of cancer cell growth in HCC.

Hepatocellular carcinoma (HCC): the most promising therapeutic targets in the preclinical arena based on tumor biology characteristics

INTRODUCTION

: Hepatocellular carcinoma (HCC) is a malignant liver tumor characterized by high molecular heterogeneity, which has hampered the development of effective targeted therapies severely. Recent experimental data have unraveled novel promising targets for HCC treatment.

AREAS COVERED

: Eligible articles were retrieved from PubMed and Web of Science databases up to July 2021. This review summarizes the established targeted therapies for advanced HCC, focusing on the strategies to overcome drug resistance and the search for combinational treatments. In addition, conventional biomarkers holding the promises for HCC treatments and novel therapeutic targets from the research field are discussed.

EXPERT OPINION

: HCC is a molecularly complex disease, with several and distinct pathways playing critical roles in different tumor subtypes. Experimental models recapitulating the features of each tumor subset would be highly beneficial to design novel and more effective therapies against this disease. Furthermore, a deeper understanding of combinatorial drug synergism and the role of the tumor microenvironment in HCC will lead to improved therapeutic outcomes.

Deregulated 14-3-3ζ and methionine adenosyltransferase α1 interplay promotes liver cancer tumorigenesis in mice and humans

Methionine adenosyltransferase 1A (MAT1A) is a tumor suppressor downregulated in hepatocellular carcinoma and cholangiocarcinoma, two of the fastest rising cancers worldwide. We compared MATα1 (protein encoded by MAT1A) interactome in normal versus cancerous livers by mass spectrometry to reveal interactions with 14-3-3ζ. The MATα1/14-3-3ζ complex was critical for the expression of 14-3-3ζ. Similarly, the knockdown and small molecule inhibitor for 14-3-3ζ (BV02), and ChIP analysis demonstrated the role of 14-3-3ζ in suppressing MAT1A expression. Interaction between MATα1 and 14-3-3ζ occurs directly and is enhanced by AKT2 phosphorylation of MATα1. Blocking their interaction enabled nuclear MATα1 translocation and inhibited tumorigenesis. In contrast, overexpressing 14-3-3ζ lowered nuclear MATα1 levels and promoted tumor progression. However, tumor-promoting effects of 14-3-3ζ were eliminated when liver cancer cells expressed mutant MATα1 unable to interact with 14-3-3ζ. Taken together, the reciprocal negative regulation that MATα1 and 14-3-3ζ exert is a key mechanism in liver tumorigenesis.