Mitochondrial uncoupling and the disruption of the metabolic network in hepatocellular carcinoma

An adenosine derivative promotes mitochondrial supercomplexes reorganization and restoration of mitochondria structure and bioenergetics in a diethylnitrosamine-induced hepatocellular carcinoma model

Hepatocellular carcinoma (HCC) progression is associated with dysfunctional mitochondria and bioenergetics impairment. However, no data about the relationship between mitochondrial supercomplexes (hmwSC) formation and ATP production rates in HCC are available. Our group has developed an adenosine derivative, IFC-305, which improves mitochondrial function, and it has been proposed as a therapeutic candidate for HCC. We aimed to determine the role of IFC-305 on both mitochondrial structure and bioenergetics in a sequential cirrhosis-HCC model in rats. Our results showed that IFC-305 administration decreased the number and size of liver tumors, reduced the expression of tumoral markers, and reestablished the typical architecture of the hepatic parenchyma. The livers of treated rats showed a reduction of mitochondria number, recovery of the mtDNA/nDNA ratio, and mitochondrial length. Also, IFC-305 increased cardiolipin and phosphatidylcholine levels and promoted hmwSC reorganization with changes in the expression levels of hmwSC assembly-related genes. IFC-305 in HCC modified the expression of several genes encoding elements of electron transport chain complexes and increased the ATP levels by recovering the complex I, III, and V activity. We propose that IFC-305 restores the mitochondrial bioenergetics in HCC by normalizing the quantity, morphology, and function of mitochondria, possibly as part of its hepatic restorative effect.

Targeting metabolic reprogramming in hepatocellular carcinoma to overcome therapeutic resistance: A comprehensive review

Hepatocellular carcinoma (HCC) poses a heavy burden on human health with high morbidity and mortality rates. Systematic therapy is crucial for advanced and mid-term HCC, but faces a significant challenge from therapeutic resistance, weakening drug effectiveness. Metabolic reprogramming has gained attention as a key contributor to therapeutic resistance. Cells change their metabolism to meet energy demands, adapt to growth needs, or resist environmental pressures. Understanding key enzyme expression patterns and metabolic pathway interactions is vital to comprehend HCC occurrence, development, and treatment resistance. Exploring metabolic enzyme reprogramming and pathways is essential to identify breakthrough points for HCC treatment. Targeting metabolic enzymes with inhibitors is key to addressing these points. Inhibitors, combined with systemic therapeutic drugs, can alleviate resistance, prolong overall survival for advanced HCC, and offer mid-term HCC patients a chance for radical resection. Advances in metabolic research methods, from genomics to metabolomics and cells to organoids, help build the HCC metabolic reprogramming network. Recent progress in biomaterials and nanotechnology impacts drug targeting and effectiveness, providing new solutions for systemic therapeutic drug resistance. This review focuses on metabolic enzyme changes, pathway interactions, enzyme inhibitors, research methods, and drug delivery targeting metabolic reprogramming, offering valuable references for metabolic approaches to HCC treatment.

SUV39H1 is a novel biomarker targeting oxidative phosphorylation in hepatitis B virus-associated hepatocellular carcinoma

BACKGROUND

As a histone methyltransferase, suppressor of variegation 3-9 homolog 1 (SUV39H1) plays an important role in the occurrence and development of cancer. To explore the mechanism and biological function of SUV39H1 in hepatitis B virus-associated hepatocellular carcinoma (HBV-HCC) can gain an insight into the pathogenesis of HBV-HCC.

METHODS

The effect of HBV infection on SUV39H1 in hepatoma cells was detected. CCK-8, colony growth assay and wound healing assay were used to assess the proliferation and migration of HBV-positive hepatoma cells. RNA sequencing (RNA-seq) was applied to find differential genes and enriched pathways. The serum SUV39H1 level in HBV-HCC patients was detected and its correlation with clinical indicators was analyzed.

RESULTS

SUV39H1 was increased by HBV infection and promoted the proliferation and migration of hepatoma cells. SUV39H1 could upregulate the expression of mitochondrial oxidative phosphorylation (OXPHOS) pathway-related genes. OXPHOS pathway inhibitors could reduce the capacity of proliferation and migration of hepatoma cells after overexpressing SUV39H1. Serum SUV39H1 levels were higher in chronic hepatitis B (CHB) patients than in healthy controls and higher in HBV-HCC patients than in CHB patients. In the diagnosis of HCC, the predictive value of SUV39H1 combined with alpha-fetoprotein (AFP) was better than that of AFP alone.

CONCLUSION

SUV39H1 is regulated by HBV infection and promotes the proliferation and migration of hepatoma cells by targeting OXPHOS pathway. It indicates that SUV39H1 may be a new biomarker of the diagnosis of HCC.

Anti-neoplastic sulfonamides alter the metabolic homeostasis and disrupt the suppressor activity of regulatory T cells

Regulatory T cells (Tregs) are essential to maintain self-tolerance and immune homeostasis but, as components of the tumor microenvironment (TME), are also a major barrier to effective cancer immunosurveillance and immunotherapy. FH535 and its derivative Y3 are two N-aryl-benzene-sulfonamides (NABs) that inhibit HCC cell proliferation and tumor progression. However, the impact of NABs on the immune cells in the TME is not yet known. Analyses of explanted livers from patients with hepatocellular carcinoma (HCC) showed that high levels of tumor-infiltrating Tregs were associated with poor tumor differentiation. These results lead us to investigate the immunomodulatory effects of NABs in regulatory and effector T cells. Exposure of primary human Tregs to NABs induced a rapid but temporary increase of cell expansion, a gradual disruption of suppressor activity, and concomitant bioenergetics and autophagic flux dysregulations. In contrast to Tregs, no gross effects were observed in effector T cells. Addition of Rapamycin prevented the functional decay of Tregs and restored their metabolic profile, suggesting that NAB effects require the integrity of the mTOR pathway. This study revealed the immunomodulatory properties of NABs with a preferential impact on Treg activity and provided novel insights into the anti-tumor potential of sulfonamides.

The multifaceted roles of mitochondria at the crossroads of cell life and death in cancer

Mitochondria are the cytoplasmic organelles mostly known as the "electric engine" of the cells; however, they also play pivotal roles in different biological processes, such as cell growth/apoptosis, Ca²⁺ and redox homeostasis, and cell stemness. In cancer cells, mitochondria undergo peculiar functional and structural dynamics involved in the survival/death fate of the cell. Cancer cells use glycolysis to support macromolecular biosynthesis and energy production ("Warburg effect"); however, mitochondrial OXPHOS has been shown to be still active during carcinogenesis and even exacerbated in drug-resistant and stem cancer cells. This metabolic rewiring is associated with mutations in genes encoding mitochondrial metabolic enzymes ("oncometabolites"), alterations of ROS production and redox biology, and a fine-tuned balance between anti-/proapoptotic proteins. In cancer cells, mitochondria also experience dynamic alterations from the structural point of view undergoing coordinated cycles of biogenesis, fusion/fission and mitophagy, and physically communicating with the endoplasmic reticulum (ER), through the Ca²⁺ flux, at the MAM (mitochondria-associated membranes) levels. This review addresses the peculiar mitochondrial metabolic and structural dynamics occurring in cancer cells and their role in coordinating the balance between cell survival and death. The role of mitochondrial dynamics as effective biomarkers of tumor progression and promising targets for anticancer strategies is also discussed.

Mitochondrial Metabolic Signatures in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide. HCC progression and metastasis are closely related to altered mitochondrial metabolism, including mitochondrial stress responses, metabolic reprogramming, and mitoribosomal defects. Mitochondrial oxidative phosphorylation (OXPHOS) defects and reactive oxygen species (ROS) production are attributed to mitochondrial dysfunction. In response to oxidative stress caused by increased ROS production, misfolded or unfolded proteins can accumulate in the mitochondrial matrix, leading to initiation of the mitochondrial unfolded protein response (UPR^mt). The mitokines FGF21 and GDF15 are upregulated during UPR^mt and their levels are positively correlated with liver cancer development, progression, and metastasis. In addition, mitoribosome biogenesis is important for the regulation of mitochondrial respiration, cell viability, and differentiation. Mitoribosomal defects cause OXPHOS impairment, mitochondrial dysfunction, and increased production of ROS, which are associated with HCC progression in mouse models and human HCC patients. In this paper, we focus on the role of mitochondrial metabolic signatures in the development and progression of HCC. Furthermore, we provide a comprehensive review of cell autonomous and cell non-autonomous mitochondrial stress responses during HCC progression and metastasis.

Metabolic Rewiring in Radiation Oncology Toward Improving the Therapeutic Ratio

To meet the anabolic demands of the proliferative potential of tumor cells, malignant cells tend to rewire their metabolic pathways. Although different types of malignant cells share this phenomenon, there is a large intracellular variability how these metabolic patterns are altered. Fortunately, differences in metabolic patterns between normal tissue and malignant cells can be exploited to increase the therapeutic ratio. Modulation of cellular metabolism to improve treatment outcome is an emerging field proposing a variety of promising strategies in primary tumor and metastatic lesion treatment. These strategies, capable of either sensitizing or protecting tissues, target either tumor or normal tissue and are often focused on modulating of tissue oxygenation, hypoxia-inducible factor (HIF) stabilization, glucose metabolism, mitochondrial function and the redox balance. Several compounds or therapies are still in under (pre-)clinical development, while others are already used in clinical practice. Here, we describe different strategies from bench to bedside to optimize the therapeutic ratio through modulation of the cellular metabolism. This review gives an overview of the current state on development and the mechanism of action of modulators affecting cellular metabolism with the aim to improve the radiotherapy response on tumors or to protect the normal tissue and therefore contribute to an improved therapeutic ratio.