Ferroptosis in liver cancer: a key role of post-translational modifications

Research progress on the mechanism of tumor cell ferroptosis regulation by epigenetics

Cancer remains a significant barrier to human longevity and a leading cause of mortality worldwide. Despite advancements in cancer therapies, challenges such as cellular toxicity and drug resistance to chemotherapy persist. Regulated cell death (RCD), once regarded as a passive process, is now recognized as a programmed mechanism with distinct biochemical and morphological characteristics, thereby presenting new therapeutic opportunities. Ferroptosis, a novel form of RCD characterized by iron-dependent lipid peroxidation and unique mitochondrial damage, differs from apoptosis, autophagy, and necroptosis. It is driven by reactive oxygen species (ROS)-induced lipid peroxidation and is implicated in tumorigenesis, anti-tumor immunity, and resistance, particularly in tumors undergoing epithelial-mesenchymal transition. Moreover, ferroptosis is associated with ischemic organ damage, degenerative diseases, and aging, regulated by various cellular metabolic processes, including redox balance, iron metabolism, and amino acid, lipid, and glucose metabolism. This review focuses on the role of epigenetic factors in tumor ferroptosis, exploring their mechanisms and potential applications in cancer therapy. It synthesizes current knowledge to provide a comprehensive understanding of epigenetic regulation in tumor cell ferroptosis, offering insights for future research and clinical applications.

Targeting ferroptosis: the role of non-coding RNAs in hepatocellular carcinoma progression and therapy

One of the most common tumors is hepatocellular carcinoma (HCC), and the prognosis for late-stage HCC is still not good. It is anticipated that improved outcomes would result from a deeper comprehension of the pathophysiology of HCC. Ferroptosis as a new discovered cell death type is linked to the progression of HCC and may be crucial for its detection, prevention, therapy, and prognosis. Numerous studies suggest that epigenetic alterations mediated by non-coding RNAs (ncRNA) might influence cancer cell susceptibility to ferroptosis. This study elucidates the processes of ferroptosis and delineates the paths by which ncRNAs influence HCC by modulating ferroptosis. Furthermore, it offers significant insights into ferroptosis-associated ncRNAs, intending to discover novel therapeutic approaches for HCC. It also explores innovative concepts for the future use of ncRNA-based ferroptosis-targeted therapeutics.

Bibliometric and graphical analysis of ferroptosis and aging research: Trends, gaps, and future directions

Over the past 12 years, a significant body of evidence derived from extensive research has underscored the pivotal involvement of ferroptosis in the mechanisms underlying aging. Despite the growing body of literature on this topic, there remains a paucity of analytical and descriptive studies that explore its trajectory, key research directions, current trends, primary focal points, and future outlooks. This research endeavors to provide an exhaustive overview of the advancements in understanding the relationship between ferroptosis and aging over the past 12 years. The dataset utilized in this study was extracted from the Web of Science, encompassing records from January 1, 2012, through June 19, 2024. We conducted comprehensive bibliometric and visual analyses using advanced analytical tools. The results highlight China's dominant contribution, which accounts for 48.52 % of total publications, positioning it as a key player in this research area. Leading institutions, including Columbia University, Southern Medical University, and the Salk Institute for Biological Studies, demonstrate high research productivity. Pamela Maher and Gu Wei are identified as the most prolific researchers in this field. Free Radical Biology and Medicine is the leading journal, publishing the most articles in this field. This study identifies mitochondrial diseases, arrhythmias, Parkinson's disease, hepatocellular carcinoma, and iron-refractory iron deficiency anemia as the key diseases investigated in this field. This bibliometric evaluation offers critical perspectives for both experienced scholars and early-career researchers, enabling the identification of novel ideas and advancements within this domain.

Chlorogenic acid induces hepatocellular carcinoma cell ferroptosis via PTGS2/AKR1C3/GPX4 axis-mediated reprogramming of arachidonic acid metabolism

BACKGROUND

Ferroptosis is an iron-dependent programmed non-apoptotic cell death characterized by the accumulation of free iron ions and lipid peroxidation. It is associated with the inactivation of glutathione peroxidase (GPX) and the accumulation of lipid peroxides within cells. Ferroptosis is closely related to the occurrence and development of hepatocellular carcinoma (HCC). Chlorogenic acid (CGA), an important bioactive component found in 61 traditional Chinese medicines such as Eucommia ulmoides, has been extensively studied for its effects on various malignant tumors. However, the specific role and potential mechanism of CGA in HCC remain unclear.

AIM

To elucidate the anti-tumor characteristics and potential mechanisms of CGA in inducing ferroptosis in HCC cells.

METHODS

The effects of CGA on the proliferation, migration, and invasion of HCC cells were evaluated through in vitro experiments. Bioinformatics analysis combined with network pharmacology was used to study the potential targets and molecular mechanisms of CGA intervention in HCC ferroptosis. In vitro experiments were conducted to verify and explore the anti-HCC effects and mechanisms of CGA through the ferroptosis pathway.

RESULTS

In vitro experiments showed that CGA dose-dependently inhibited the proliferation, invasion, and migration of HCC cells. Bioinformatics analysis combined with network pharmacology revealed that the pathway of CGA intervention in HCC cell ferroptosis was mainly enriched in the prostaglandin endoperoxide synthase 2 (PTGS2)/aldo-keto reductase family 1 member C3 (AKR1C3)/GPX4 signaling pathway, which was associated with arachidonic acid. In vitro experiments further confirmed that CGA-induced ferroptosis in HCC cells was related to mitochondrial damage through the reprogramming of arachidonic acid metabolism by regulating the PTGS2/AKR1C3/GPX4 signaling pathway.

CONCLUSION

This study demonstrates that CGA inhibits HCC cell proliferation, migration, and invasion by inducing ferroptosis through the PTGS2/AKR1C3/GPX4 axis, suggesting its potential as a novel ferroptosis inducer or anti-HCC drug.

[Causal relationship between ferroptosis-related gene HSPA5 and hepatocellular carcinoma: a study based on mendelian randomization and mediation analysis]

OBJECTIVES

To explore a causal relationship between ferroptosis-related gene heat shock protein A5 (HSPA5) and hepatocellular carcinoma (HCC).

METHODS

A two-sample Mendelian randomization (MR) design was employed to evaluate the causal relationships among HSPA5, regulatory T cells (Tregs), and HCC. Single nucleotide polymorphisms (SNPs) associated with HSPA5, Tregs and HCC were selected as instrumental variables through publicly available genome-wide association studies (GWAS) databases. MR analysis was used to assess the direct effect of HSPA5 on HCC, followed by two-step MR to analyze the potential mediating role of Tregs. Reverse MR analysis was conducted with HCC as the exposure and HSPA5 as the outcome. Inverse variance weighting was the primary method for testing causal associations in all MR analyses. Robustness of the results was confirmed through MR-Egger, weighted median, weighted mode, and simple mode methods. Heterogeneity of instrumental variables was evaluated using Cochrane's Q statistic, while pleiotropy was tested by MR-Egger intercept and MR-PRESSO, with leave-one-out sensitivity analysis performed for robustness. Data from The Cancer Genome Atlas (TCGA) and Human Protein Atlas (HPA) were utilized to verify the expression levels of HSPA5 in HCC tissues and its correlation with Tregs to reveal the interaction mechanisms between HSPA5 and Tregs in HCC progression and their relationship with patient prognosis.

RESULTS

MR analysis showed a positive correlation between elevated HSPA5 expression and HCC risk (all P<0.01), while reverse MR analysis found no statistically significant association between HCC and HSPA5 (P>0.05). HSPA5 expression was significantly correlated with Tregs function (all P<0.05), and the enrichment of Tregs in HCC microenvironment was positively associated with HCC progression (all P<0.05). Mediation analysis indicated that Tregs accounted for 5.00% and 7.45% of the mediation effect between HSPA5 and HCC. TCGA and HPA database analysis revealed that both HSPA5 mRNA and protein expression levels were higher in HCC tissues compared to normal tissues, and high HSPA5 expression was significantly associated with poor prognosis. Immune infiltration analysis confirmed a significant positive correlation between HSPA5 and Tregs, with high Tregs infiltration closely related to HCC progression.

CONCLUSIONS

Elevated HSPA5 expression is significantly associated with HCC development and poor prognosis. HSPA5 may promote HCC progression by regulating the function of Tregs in the tumor microenvironment.

Emerging insights into ferroptosis in cholangiocarcinoma (Review)

Cholangiocarcinoma (CCA) is a malignant tumor that arises within the biliary system, which exhibits a progressively increasing incidence and a poor patient prognosis. A thorough understanding of the molecular pathogenesis that drives the progression of CCA is essential for the development of effective molecular target therapeutic approaches. Ferroptosis is driven by excessive iron accumulation and catalysis, lipid peroxidation and the failure of antioxidant defense systems. Key molecular targets of iron metabolism, lipid metabolism and antioxidant defense systems involve molecules such as transferrin receptor, ACSL4 and GPX4, respectively. Inhibitors of ferroptosis include ferrostatin-1, liproxstatin-1, vitamin E and coenzyme Q10. By contrast, compounds such as erastin, RSL3 and FIN56 have been identified as inducers of ferroptosis. Ferroptosis serves a notable role in the onset and progression of CCA. CCA cells exhibit high sensitivity to ferroptosis and aberrant iron metabolism in these cells increases oxidative stress and iron accumulation. The induction of ferroptosis markedly reduces the ability of CCA cells to proliferate and migrate. Certain ferroptosis agonists, such as RSL3 and erastin, cause lipid peroxide build up and GPX4 inhibition to induce ferroptosis in CCA cells. Current serological markers, such as CA-199, have low specificity and cause difficulties in the diagnosis of CCA. However, novel techniques, such as non-invasive liquid biopsy and assays for oxidative stress markers and double-cortin-like kinase 1, could improve diagnostic accuracy. CCA is primarily treated with surgery and chemotherapy. A close association between the progression of CCA with ferroptosis mechanisms and related regulatory pathways has been demonstrated. Therefore, it could be suggested that multi-targeted therapeutic approaches, such as ferroptosis inducers, iron chelating agents and novel modulators such as YL-939, may improve treatment efficacy. Iron death-related genes, such as GPX4, that are highly expressed in CCA and are associated with a poor prognosis for patients may represent potential prognostic markers for CCA. The present review focused on molecular targets such as p53 and ACSL4, the process of targeted medications in combination with PDT in CCA and the pathways of lipid peroxidation, the Xc-system and GSH-GPX4 in ferroptosis. The present review thus offered novel perspectives to improve the current understanding of CCA.