FDX1 as a novel biomarker and treatment target for stomach adenocarcinoma

A Prognostic Riskscore Model Related to Helicobacter pylori Infection in Stomach Adenocarcinoma

Background: Helicobacter pylori (HP) is associated with the development of various stomach diseases, one of the major risk factors for stomach adenocarcinoma (STAD). Methods: The HP infection score between tumor and normal groups was compared by single-sample gene set enrichment analysis (ssGSEA). The key modules related to HP infection were identified by weighted gene coexpression network analysis (WGCNA), and functional enrichment analysis was conducted on these module genes. Further, the limma package was used to screen the differentially expressed genes (DEGs) between HP-positive and HP-negative STAD. The prognostic genes were obtained to construct the riskscore model, and the performance of the model was validated. The correlation between riskscore and tumor immune microenvironment (TIME) was analyzed by Spearman's method. The single-cell atlas of HP-positive STAD was delineated. The mRNA expression levels of the prognostic genes were verified using STAD cells, and the migration and invasion capacities of STAD cells were evaluated by using the wound healing assay and transwell assay. Results: The HP infection score in the tumor group was significantly higher than that in the normal group. The purple and royal blue modules showed higher correlation with HP infection in STAD, and these module genes were enriched in the immune-related pathway. Further, five prognostic genes (CTLA4, CPVL, EMB, CXCR4, and FAM241A) were screened from the HP infection-related DEGs, which were utilized for establishing the riskscore model, with good robustness. Riskscore exhibited strong correlation with TIME in STAD. Single-cell atlas of HP-positive STAD revealed that CXCR4 is highly expressed in Epithelial Cell 1, Epithelial Cell 2, and parietal cells of the tumor group. CPVL, EMB, CTLA4, FAM241A, and CXCR4 showed high expression in STAD cells, and the silencing of CPVL could suppress the migration and invasion of STAD cells. Conclusion: This study established a riskscore model based on HP infection-related genes, which could provide reference for prognostic prediction and treatment targets of STAD.

Hypoxia-induced autophagy attenuates ferredoxin 1-mediated cuproptosis in colorectal cancer cells

IntroductionCuproptosis has emerged as a potential therapeutic target for colorectal cancer (CRC). This study investigated the role of ferredoxin 1 (FDX1) in regulating cuproptosis under hypoxic conditions and explored the impact of autophagy on this process in CRC.MethodsCRC patient samples and cell lines were used in this study. Cells were exposed to hypoxia and treated with Es-Cu (a copper supplement) and rapamycin, an autophagy inducer. FDX1 expression in clinical tissues was assessed in clinical tissues using qPCR and Western blot. The CCK8 assay, EdU staining, and Transwell assay were employed to evaluate the malignant behavior of tumor cells. Copper content and DLAT oligomerization were measured. A nude mouse xenograft model was used to explore the role of FDX1 under hypoxic conditions.ResultsCompared with adjacent normal tissues, elevated FDX1 expression was observed in CRC tissues. In vitro, hypoxia or Es-Cu treatment upregulated FDX1 expression in CRC cell lines, resulting in reduced cell proliferation and increased cellular damage. FDX1 overexpression under hypoxic conditions suppressed migration, invasion, and proliferation while promoting cellular damage and DLAT oligomerization. Rapamycin-induced autophagy reversed the inhibitory effects of FDX1 overexpression on CRC cells. In vivo, rapamycin treatment attenuated the tumor-suppressive effects of FDX1 overexpression in nude mouse xenograft models.DiscussionThis study demonstrated that hypoxia-induced autophagy inhibits FDX1-mediated cuproptosis, leading to resistance to copper-induced cell death in CRC cells. Targeting the autophagy pathway may provide a novel therapeutic strategy to overcome resistance to cuproptosis and improving CRC treatment outcomes.

The role of cuproptosis in gastric cancer

As a biologically essential transition metal, copper is widely involved in various enzymatic reactions and crucial biological processes in the body. It plays an increasingly important role in maintaining normal cellular metabolism and supporting the growth and development of the human body. As a trace element, copper maintains the dynamic balance of its concentration in body fluids through active homeostatic mechanisms. Both excess and deficiency of copper ions can impair cell function, ultimately leading to cell damage and death. Cuproptosis is a novel form of cell death where copper ions cause cell death by directly binding to the lipoylated components of the citric acid cycle (CAC) in mitochondrial respiration and interfering with the levels of iron-sulfur cluster (Fe-S cluster) proteins, ultimately causing protein toxic stress. Its primary characteristics are Cu2+ concentration dependence and high expression in mitochondrial respiratory cells. Recent research has revealed that, compared to other forms of programmed cell death such as apoptosis, necrosis, and autophagy, cuproptosis has unique morphological and biochemical features. Cuproptosis is associated with the occurrence and development of various diseases, including cancer, neurodegenerative diseases, and cardiovascular diseases. This article focuses on a review of the relevance of cuproptosis in gastric cancer (GC).