The Clinicopathologic and Prognostic Significance of c-Myc Expression in Hepatocellular Carcinoma: A Meta-Analysis

GTF3C2 Promotes the Proliferation of Hepatocellular Carcinoma Cells through the USP21/MEK2/ERK1/2 Pathway

Background and Aims

General transcription factor IIIC subunit 2 (GTF3C2) is one of the polymerase III transcription-related factors. Previous studies have revealed that GTF3C2 is involved in regulating cell proliferation. However, the role of GTF3C2 in hepatocellular carcinoma (HCC) remains unclear. This study aimed to determine its expression, biological function, and mechanism in HCC.

Methods

The expression of GTF3C2 in HCC and non-tumor tissues, along with its clinical significance, was investigated using public databases and clinical samples. Reverse transcription-quantitative polymerase chain reaction and Western blot assays were performed to detect the expression of GTF3C2, ubiquitin specific peptidase 21 (USP21), mitogen-activated protein kinase 2 (MEK2), extracellular signal-regulated kinase 1/2 (ERK1/2), and p-ERK1/2 in cells. A luciferase reporter assay was conducted to explore the regulatory effect of GTF3C2 on USP21 transcription. Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine, and colony formation assays were performed to assess HCC cell proliferation. Subcutaneous injection of HCC cells into nude mice was used to evaluate tumor growth in vivo.

Results

GTF3C2 expression was upregulated in HCC tissues and was positively correlated with advanced tumor stages and high tumor grades. HCC patients with high GTF3C2 expression had significantly worse survival outcomes. Knockdown of GTF3C2 suppressed the proliferation of Hep3B and HCCLM3 cells, while overexpression of GTF3C2 facilitated the proliferation of SNU449 and Huh7 cells. GTF3C2 promoted USP21 expression by activating its transcription, which subsequently increased the levels of MEK2 and p-ERK1/2 in HCC cells. Overexpression of both USP21 and MEK2 counteracted the GTF3C2 knockdown-induced inactivation of the ERK1/2 pathway. Moreover, GTF3C2 promoted HCC cell proliferation in vitro and tumor growth in vivo by regulating the USP21/MEK2/ERK1/2 pathway.

Conclusions

Upregulation of GTF3C2 is frequently observed in HCC tissues and predicts poor prognosis. GTF3C2 promotes HCC cell proliferation via the USP21/MEK2/ERK1/2 pathway.

Tumor Intrinsic Immunogenicity Suppressor SETDB1 Worsens the Prognosis of Patients with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is clinically distinguished by its covert onset, rapid progression, high recurrence rate, and poor prognosis. Studies have revealed that SETDB1 (SET Domain Bifurcated 1) is a histone H3 methyltransferase located on chromosome 1 and plays a crucial role in carcinogenesis. Therefore, we aimed to evaluate the clinical significance of SETDB1 expression in HCC. In patients with HCC, elevated levels of SETDB1 correlated with a poorer overall survival (OS) rate, marking it as an independent prognostic factor for HCC, as revealed by both univariate and multivariate Cox analyses. Furthermore, we utilized the SangerBox and TISIDB databases to profile the tumor immune microenvironment in HCC, including scoring the tumor microenvironment and assessing immune cell infiltration. The TIDE algorithm was employed to examine the association between SETDB1 expression and immune responses. Our findings indicated that SETDB1 expression negatively correlated with the majority of immune cells, a wide range of immune cell marker genes, and numerous immune pathways, thereby leading to the reduced effectiveness of immune checkpoint inhibitors. Lastly, both in vivo and ex vivo experiments were conducted to substantiate the role of SETDB1 in HCC tumorigenesis. In conclusion, the upregulation of SETDB1 is associated with a poorer prognosis in HCC patients and inversely correlates with immune cell infiltration, potentially serving as a predictive marker for immunotherapy response.

Targeted therapies in hepatocellular carcinoma: past, present, and future

Targeted therapies are the mainstay of systemic therapies for patients with advanced, unresectable, or metastatic hepatocellular carcinoma. Several therapeutic targets, such as c-Met, TGF-β, and FGFR, have been evaluated in the past, though results from these clinical studies failed to show clinical benefit. However, these remain important targets for the future with novel targeted agents and strategies. The Wnt/β-catenin signaling pathway, c-Myc oncogene, GPC3, PPT1 are exciting novel targets, among others, currently undergoing evaluation. Through this review, we aim to provide an overview of previously evaluated and potentially novel therapeutic targets and explore their continued relevance in ongoing and future studies for HCC.

Circulating tumor DNA and its role in detection, prognosis and therapeutics of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. It has the most frequent duplication time and a high recurrence rate. Recently, the most unique technique used is liquid biopsies, which carry many markers; the most prominent is circulating tumor DNA (ctDNA). Varied methods are used to investigate ctDNA, including various forms of polymerase chain reaction (PCR) [emulsion PCR (ePCR), digital PCR (dPCR), and bead, emulsion, amplification, magnetic (BEAMing) PCR]. Hence ctDNA is being recognized as a potential biomarker that permits early cancer detection, treatment monitoring, and predictive data on tumor burden are subjective to therapy or surgery. Numerous ctDNA biomarkers have been investigated based on their alterations such as 1) single nucleotide variations (either insertion or deletion of a nucleotide) markers including TP53, KRAS, and CCND1; 2) copy number variations which include markers such as CDK6, EFGR, MYC and BRAF; 3) DNA methylation (RASSF1A, SEPT9, KMT2C and CCNA2); 4) homozygous mutation includes ctDNA markers as CDKN2A, AXIN1; and 5) gain or loss of function of the genes, particularly for HCC. Various researchers have conducted many studies and gotten fruitful results. Still, there are some drawbacks to ctDNA namely low quantity, fragment heterogeneity, less stability, limited mutant copies and standards, and differential sensitivity. However, plenty of investigations demonstrate ctDNA's significance as a polyvalent biomarker for cancer and can be viewed as a future diagnostic, prognostic and therapeutic agent. This article overviews many conditions in genetic changes linked to the onset and development of HCC, such as dysregulated signaling pathways, somatic mutations, single-nucleotide polymorphisms, and genomic instability. Additionally, efforts are also made to develop treatments for HCC that are molecularly targeted and to unravel some of the genetic pathways that facilitate its early identification.

Role of Fibrinogen-like Protein 1 in Tumor Recurrence Following Hepatectomy

Partial hepatectomy is a first-line treatment for hepatocellular carcinoma. Within 2 weeks following partial hepatectomy, specific molecular pathways are activated to promote liver regeneration. Nevertheless, residual microtumors may also exploit these pathways to reappear and metastasize. Therapeutically targeting molecules that are differentially regulated between normal cells and malignancies, such as fibrinogen-like protein 1 (FGL1), appears to be an effective approach. The potential functions of FGL1 in both regenerative and malignant cells are discussed within the ambit of this review. While FGL1 is normally elevated in regenerative hepatocytes, it is normally downregulated in malignant cells. Hepatectomy does indeed upregulate FGL1 by increasing the release of transcription factors that promote FGL1, including HNF-1α and STAT3, and inflammatory effectors, such as TGF-β and IL6. This, in turn, stimulates certain proliferative pathways, including EGFR/Src/ERK. Hepatectomy alters the phase transition of highly differentiated hepatocytes from G0 to G1, thereby transforming susceptible cells into cancerous ones. Activation of the PI3K/Akt/mTOR pathway by FGL1 allele loss on chromosome 8, a tumor suppressor area, may also cause hepatocellular carcinoma. Interestingly, FGL1 is specifically expressed in the liver via HNF-1α histone acetylase activity, which triggers lipid metabolic reprogramming in malignancies. FGL1 might also be involved in other carcinogenesis processes such as hypoxia, epithelial-mesenchymal transition, immunosuppression, and sorafenib-mediated drug resistance. This study highlights a research gap in these disciplines and the necessity for additional research on FGL1 function in the described processes.

Alleviation of doxorubicin adverse effects via loading into various drug-delivery systems: a comparative study

Aim: Drug resistance is still a significant barrier to effective hepatocellular carcinoma therapy. Address the issue of doxorubicin resistance and inter-receptor crosstalk various doxorubicin formulations were investigated. Methods: Hepatocellular carcinoma was carried out using 3-methylechloroanthrene. Animals were then treated with doxorubicin, liposomal doxorubicin, titanium-loaded doxorubicin (TiO2-Dox), lactoferrin-doxorubicin and PEGylated doxorubicin. Biochemical and molecular analyses were assessed. Results: Results have declared a significant alternation of both sodium and potassium concentrations upon 3-methylechloroanthrene administration. Arginase-I and α-L-Fucodinase tumor biomarkers were significantly elevated. C-myc, Hprt-1 and EGFR gene expression were over-expressed. Treatment with the aforementioned treatment regimens significantly modulated all measured parameters. Conclusion: TiO2-Dox, doxorubicin-lactoferrin and PEGylated doxorubicin could be a promising regimen in hepatocellular carcinoma and overcoming the problem of drug resistance.

High Ki67 Gene Expression Is Associated With Aggressive Phenotype in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) with high Ki67 protein expression, the most commonly used cell proliferation marker, is associated with an aggressive biologic phenotype; however, conventional immunostaining is hampered by variability in institutional protocol, specific antibody probe, and by assessor subjectivity. To this end, we hypothesized that Ki67 gene (MKi67) expression would identify highly proliferative HCC, and clarify its association with oncologic outcome, tumor progression, and immune cell population in the tumor microenvironment (TME). Furthermore, we sought to identify the cell-cycle gene expression profile that confers this aggressive phenotype.

METHODS

A total of 473 HCC patients with clinicopathological data associated with transcriptome were selected for this study: 358 patients from The Cancer Genome Atlas (TCGA) as the testing cohort, and 115 from GSE76427 as the validation cohort. Each cohort was divided into a highly proliferative group (MKi67-high) and the low MKi67 group (MKi67-low) by the median of Ki67 gene (MKi67) expression levels.

RESULTS

MKi67-high HCC patients had worse disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS) independent of histological grade in the TCGA cohort. MKi67 expression correlated with histological grade and tumor size. MKi67 expression increased throughout the HCC carcinomatous sequence from normal liver, cirrhotic liver, early HCC, and advanced HCC. MKi67-high HCC was associated with higher intratumor heterogeneity, homologous recombination deficiency, and altered fraction as well as intratumoral infiltration of T helper type 1 (Th1) and Th2 cells, but lower interferon-gamma response and M2 macrophage infiltration. Cell proliferation-related gene sets in the Hallmark collection (E2F targets, G2M checkpoint, Myc target v1 and mitotic spindle), MTORC1 signaling, DNA repair, PI3K MTOR signaling, and unfolded protein response were all enriched in the MKi67-high HCC (false discovery rate (FDR) < 0.25).

CONCLUSIONS

High MKi67 gene expression identified highly proliferative HCC with aggressive biology involving classical pathways in cell cycle regulation and DNA repair, as well as poor overall oncologic outcomes. This suggests potential for personalized treatment strategies, but validation and refinement of these observations require further research to elucidate the underlying mechanisms and validate therapeutic targeting of these pathways in MKi67-high HCC tumors.

Cancer cell genetics shaping of the tumor microenvironment reveals myeloid cell-centric exploitable vulnerabilities in hepatocellular carcinoma

Myeloid cells are abundant and plastic immune cell subsets in the liver, to which pro-tumorigenic, inflammatory and immunosuppressive roles have been assigned in the course of tumorigenesis. Yet several aspects underlying their dynamic alterations in hepatocellular carcinoma (HCC) progression remain elusive, including the impact of distinct genetic mutations in shaping a cancer-permissive tumor microenvironment (TME). Here, in newly generated, clinically-relevant somatic female HCC mouse models, we identify cancer genetics' specific and stage-dependent alterations of the liver TME associated with distinct histopathological and malignant HCC features. Mitogen-activated protein kinase (MAPK)-activated, NrasG12D-driven tumors exhibit a mixed phenotype of prominent inflammation and immunosuppression in a T cell-excluded TME. Mechanistically, we report a NrasG12D cancer cell-driven, MEK-ERK1/2-SP1-dependent GM-CSF secretion enabling the accumulation of immunosuppressive and proinflammatory monocyte-derived Ly6Clow cells. GM-CSF blockade curbs the accumulation of these cells, reduces inflammation, induces cancer cell death and prolongs animal survival. Furthermore, GM-CSF neutralization synergizes with a vascular endothelial growth factor (VEGF) inhibitor to restrain HCC outgrowth. These findings underscore the profound alterations of the myeloid TME consequential to MAPK pathway activation intensity and the potential of GM-CSF inhibition as a myeloid-centric therapy tailored to subsets of HCC patients.

Identification and validation of microtubule depolymerizing agent, CYT997, as a potential drug candidate for hepatocellular carcinoma

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is a typically fatal malignancy with limited treatment options and poor survival rates, despite recent FDA approvals of newer treatment options. We aim to address this unmet need by using a proprietary computational drug discovery platform that identifies drug candidates with the potential to advance rapidly and successfully through preclinical studies.

METHODS

We generated an in silico model of HCC biology to identify the top 10 small molecules with predicted efficacy. The most promising candidate, CYT997, was tested for its in vitro effects on cell viability and cell death, colony formation, cell cycle changes, and cell migration/invasion in HCC cells. We used an HCC patient-derived xenograft (PDX) mouse model to assess its in vivo efficacy.

RESULTS

CYT997 was significantly more cytotoxic against HCC cells than against primary human hepatocytes, and sensitized HCC cells to sorafenib. It arrested cell cycle at the G2/M phase with associated up-regulations of p21, p-MEK1/2, p-ERK, and down-regulation of cyclin B1. Cell apoptosis and senescence-like morphology were also observed. CYT997 inhibited HCC cell migration and invasion, and down-regulated the expressions of acetylated tubulins, β-tubulin, glypican-3 (GPC3), β-catenin, and c-Myc. In vivo, CYT997 (20 mg/kg, three times weekly by oral gavage) significantly inhibited PDX growth, while being non-toxic to mice. Immunohistochemistry confirmed the down-regulation of GPC3, c-Myc, and Ki-67, supporting its anti-proliferative effect.

CONCLUSION

CYT997 is a potentially efficacious and non-toxic drug candidate for HCC therapy. Its ability to down-regulate GPC3, β-catenin, and c-Myc highlights a novel mechanism of action.

Molecular Targets and Signaling Pathways of microRNA-122 in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading global causes of cancer mortality. MicroRNAs (miRNAs) are small interfering RNAs that alleviate the levels of protein expression by suppressing translation, inducing mRNA cleavage, and promoting mRNA degradation. miR-122 is the most abundant miRNA in the liver and is responsible for several liver-specific functions, including metabolism, cellular growth and differentiation, and hepatitis virus replication. Recent studies have shown that aberrant regulation of miR-122 is a key factor contributing to the development of HCC. In this review, the signaling pathways and the molecular targets of miR-122 involved in the progression of HCC have been summarized, and the importance of miR-122 in therapy has been discussed.