Cuproptosis-related gene DLAT serves as a prognostic biomarker for immunotherapy in clear cell renal cell carcinoma: multi-database and experimental verification

Aberrant DNA methylation as a key modulator of cell death pathways: insights into cancer progression and other diseases

Cell death plays a significant role in the physiology of all living organisms, and its disruption is the underlying cause of various diseases. Previously, it was assumed that apoptosis and necrosis were the only means of cell death. Recent discoveries of alternative cell death pathways highlighted a complicated interplay between cell death regulation and its role in numerous human pathologies. DNA methylation is a universal epigenetic mechanism characterized by the covalent addition of a methyl group to cytosine in CpG dinucleotides. Alterations in DNA methylation patterns lead to the dysregulation of multiple cell death pathways. DNA methylome studies on cell death pathways have improved our understanding of the mechanism of various types of cell death, such as apoptosis, pyroptosis, necroptosis, ferroptosis, anoikis, autophagy, and cuproptosis. The irregular DNA methylation patterns of genes encoding proteins linked to multiple cell death pathways could underlie resistance to cell death. Dysregulation of cell death is linked to ailments in humans, such as cancer. However, unlike genetic alterations, DNA methylation is reversible, making it extremely interesting for therapeutics considering the potential use of DNA methyltransferase inhibitors. Furthermore, tumor microenvironment and genetic heterogeneity of cancers may influence the methylation-dependent regulation of cell death, contributing to tumor progression and therapeutic resistance. Understanding how DNA methylation influences cell death pathways may illuminate the underlying causes of cancer. This review explores the significance of the DNA methylation patterns of key genes involved in cell death pathways, emphasizing their connections and identifying potential gaps that could be exploited for developing epigenetic therapies targeting cancer.

Diagnostic and prognostic potential of FBXO8 expression in kidney renal clear cell carcinoma and its regulation of renal adenocarcinoma cells

BACKGROUND

The F-box protein 8 Gene (FBXO8) has been shown to suppress invasion and metastasis in various cancer types. Recurrence and drug resistance pose significant challenges in renal cell carcinoma (RCC). Identifying novel biomarkers is crucial for addressing these issues.

METHODS

Data on RNA sequencing and patient survival for KIRC was obtained from The Cancer Genome Atlas (TCGA), UALCAN, and Gene Expression Omnibus (GEO) databases. We confirmed FBXO8 gene expression and its impact on survival. Clinical characteristics were classified, and FBXO8 expression differences among various categories were observed. We conducted biofunctional predictions and analyzed the tumor microenvironment (TME), immune cell infiltration, and immune checkpoints in relation to FBXO8 expression. FBXO8 was overexpressed using a plasmid, and we assessed Kidney renal clear cell carcinoma (KIRC) cell proliferation, migration, and apoptosis through CCK8, wound healing tests, and western blot analysis.

RESULTS

Our findings revealed decreased FBXO8 expression in KIRC, with patients exhibiting low FBXO8 expression experiencing shorter survival times. The low expression group showed elevated TME immune and estimate scores. Biofunctional analyses indicated that FBXO8 expression was notably linked to drug metabolism cytochrome P450, nutrition disease, receptor-ligand activity, and neuroactive ligand-receptor interaction. Furthermore, we discovered significant correlations between FBXO8 expression and immune cell infiltration, as well as checkpoints such as CD274. Overexpression (OE) of FBXO8 led to a marked reduction in cell proliferation and migration, along with increased apoptosis, as evidenced by apoptosis-related protein expression.

CONCLUSION

This study demonstrates that FBXO8 serves as a biomarker for KIRC and plays a role in regulating cell proliferation, migration, and apoptosis.

DLAT promotes triple-negative breast cancer progression via YAP1 activation

BACKGROUND

Breast cancer (BC) is the most prevalent malignant tumor in women globally. Triple-negative breast cancer (TNBC) represents the most malignant and invasive subtype of BC. New therapeutic targets are urgently needed for TNBC owing to its receptor expression characteristics, which render it insensitive to traditional targeted and endocrine therapies for BC. The role and mechanisms of dihydrolipoamide S-acetyltransferase (DLAT) as a crucial molecule in glycometabolism and cuproptosis-related biological processes in tumors remain to be explored.

METHODS

DLAT expression was investigated using bioinformatics methods and quantitative real-time polymerase chain reaction. Subsequently, the MTT assay, colony formation assay, and migration-invasion assay were performed to validate the effect of DLAT on TNBC cell viability, proliferation, and migration. Cytoplasmic-nuclear separation experiments, western blot analysis, and co-immunoprecipitation assays were performed to elucidate the underlying molecular mechanisms.

RESULTS

This study revealed a robust correlation between elevated DLAT expression in BC and unfavorable prognosis in patients, with higher expression of DLAT compared to other subtypes in TNBC. Functional cytology experiments indicated that DLAT plays a tumor-promoting role in TNBC. Mechanistic studies showed that DLAT directly interacts with YAP1, leading to the dephosphorylation and activation of YAP1 and its increased nuclear translocation, thereby transcriptionally activating and regulating downstream oncogenes, promoting the malignant phenotype of TNBC. Rescue experiments indicated that DLAT promotes the malignant behavior of TNBC through a YAP1-dependent pathway.

CONCLUSIONS

Our research unveiled the significant involvement of DLAT in TNBC, along with the potential for modulating DLAT/YAP1 activity as a targeted treatment strategy for TNBC.

Cuproptosis-related gene DLAT is a biomarker of the prognosis and immune microenvironment of gastric cancer and affects the invasion and migration of cells

OBJECTIVE

Cuproptosis is a novel cell death dependent on mitochondrial respiration and regulated by copper. This study aimed to investigate the cuproptosis-related gene DLAT potential value in gastric cancer (GC).

METHODS

Bioinformatics was used to analyze DLAT expression. DLAT expression in GC cell lines was detected using qRT-PCR. Cell proliferation ability was assessed using CCK8 and cell cycle assay. Cell migration and invasion were assessed using wound healing and transwell assay. A prognostic assessment was performed through survival and Cox regression analysis. DLAT protein expression was analyzed through HPA immunohistochemistry. Biological functions and processes were analyzed through GO and KEGG enrichment analysis and PPI. Correlation with immune cell infiltration and immune checkpoint genes was analyzed for DLAT.

RESULTS

DLAT expression was upregulated in GC tissues and cells and correlated with shorter survival for patients. Age, gender, histological typing, lymph node metastasis, and distant metastasis were identified as independent prognostic factors affecting OS in GC. DLAT protein was upregulated in GC. The biological functions and pathways enriched in DLAT were mainly linked to mitochondrial respiration and the TCA cycle. The expression of DLAT was found to be positively correlated with the infiltration of Th and Th2 immune cells and only positively correlated with the expression of the BTN2A1 immune checkpoint gene.

CONCLUSION

DLAT has the potential to serve as a prognostic assessment factor in GC. The expression of DLAT was correlated with immune infiltration and tumor immune escape, providing a new target for immunotherapy of GC.

Targeting cuproplasia and cuproptosis in cancer

Copper, an essential trace element that exists in oxidized and reduced forms, has pivotal roles in a variety of biological processes, including redox chemistry, enzymatic reactions, mitochondrial respiration, iron metabolism, autophagy and immune modulation; maintaining copper homeostasis is crucial as both its deficiency and its excess are deleterious. Dysregulated copper metabolism has a dual role in tumorigenesis and cancer therapy. Specifically, cuproplasia describes copper-dependent cell growth and proliferation, including hyperplasia, metaplasia and neoplasia, whereas cuproptosis refers to a mitochondrial pathway of cell death triggered by excessive copper exposure and subsequent proteotoxic stress (although complex interactions between cuproptosis and other cell death mechanisms, such as ferroptosis, are likely and remain enigmatic). In this Review, we summarize advances in our understanding of copper metabolism, the molecular machineries underlying cuproplasia and cuproptosis, and their potential targeting for cancer therapy. These new findings advance the rapidly expanding field of translational cancer research focused on metal compounds.

Diabetic Cardiomyopathy and Cell Death: Focus on Metal-Mediated Cell Death

Cardiac myocyte death is an essential initiator of the pathogenesis and progression of various etiological cardiomyopathies, including diabetic cardiomyopathy (DCM), a disease that has been reported since 1972. Cardiac cell death has been detected in the hearts of patients with diabetes and in animal models, and the role of cell death in the pathogenesis of DCM has been extensively investigated. The first review by the authors, specifically focusing on "Cell death and diabetic cardiomyopathy," was published in the journal, Cardiovascular Toxicology in 2003. Over the past two decades, studies investigating the role of cardiac cell death in the pathogenesis of DCM have gained significant attention, resulting in the discovery of several new kinds of cell death involving different mechanisms, including apoptosis, necroptosis, pyroptosis, autophagy, ferroptosis, and cuproptosis. After the 20th anniversary of the review published in 2003, we now provide an update with a focus on the potential role of metal-mediated cell death, ferroptosis, and cuproptosis in the development of DCM in compliance with this special issue. The intent of our review is to further stimulate work in the field to advance the body of knowledge and continue to drive efforts to develop more advanced therapeutic approaches to prevent cell death, particularly metal-dependent cell death, and, ultimately, to reduce or prevent the development of DCM.