N6-methylandenosine-related immune genes correlate with prognosis and immune landscapes in gastric cancer

N6-methyladenosine RNA modification in stomach carcinoma: Novel insights into mechanisms and implications for diagnosis and treatment

N6-methyladenosine (m6A) RNA methylation is crucially involved in the genesis and advancement of gastric cancer (GC) by controlling various pathobiological aspects including gene expression, signal transduction, metabolism, cell death, epithelial-mesenchymal transition, angiogenesis, and exosome function. Despite its importance, the exact mechanisms by which m6A modification influences GC biology remain inadequately explored. This review consolidates the latest advances in uncovering the mechanisms and diverse roles of m6A in GC and proposes new research and translational directions. Key regulators (writers, readers, and erasers) of m6A, such as METTL3/14/16 and WTAP, significantly affect cancer progression, anticancer immune response, and treatment outcomes. m6A modification also impacts immune cell infiltration and the tumor microenvironment, highlighting its potential as a diagnostic and prognostic marker. Interactions between m6A methylation and non-coding RNAs offer further novel insights into GC development and therapeutic targets. Targeting m6A regulators could enhance immunotherapy response, overcome treatment resistance, and improve oncological and clinical outcomes. Models based on m6A can precisely predict treatment response and prognosis in GC. Additional investigation is needed to fully understand the mechanisms of m6A methylation and its potential clinical applications and relevance (e.g., as precise markers for early detection, prediction of outcome, and response to therapy and as therapeutic targets) in GC. Future research should focus on in vivo studies, potential clinical trials, and the examination of m6A modification in other types of cancers.

Exploring m6A modifications in gastric cancer: from molecular mechanisms to clinical applications

The significance of m6A modifications in several biological processes has been increasingly recognized, particularly in the context of cancer. For instance, m6A modifications in gastric cancer (GC) have been significantly implicated in tumor progression, metastasis, and treatment resistance. GC is characterized by the differential expression of m6A regulators. High expression writers such as METTL3 and WTAP are associated with poor prognosis and aggressive clinical features. Conversely, low expression of METTL14 is linked to worse clinical outcomes, whereas elevated levels of demethylases, such as FTO and ALKBH5, correlate with better survival rates. These m6A regulators influence several cellular biological functions, including proliferation, invasion, migration, glycolysis, and chemotherapy resistance, thereby affecting tumor growth and therapeutic outcomes. The assessment of m6A modification patterns and the expression profiles of m6A-related genes hold substantial potential for improving the clinical diagnosis and treatment of GC. In this review, we provide an updated and comprehensive summary of the role of m6A modifications in GC, emphasizing their molecular mechanisms, clinical significance, and translational applications in developing novel diagnostic and therapeutic strategies.

High expression of AlkB homolog 5 suppresses the progression of non-small cell lung cancer by facilitating ferroptosis through m6A demethylation of SLC7A11

OBJECTIVE

Non-small cell lung cancer (NSCLC) is a prevailing LC characterized by poor outcomes. AlkB homolog 5 (ALKBH5) functions as a tumor suppressor in several cancers. This study delved into the role of ALKBH5 in NSCLC development.

METHODS

TCGA database predicted ALKBH5 expression in NSCLC patients. ALKBH5 levels in NSCLC and human bronchial epithelial cells were determined. pcDNA3.1-ALKBH5/NC, pcDNA3.1-SLC7A11/NC, and ferrostatin-1 were used to explore the interactions among ALKBH5, SLC7A11, and ferroptosis. SLC7A11 mRNA and its protein levels were measured by RT-qPCR and Western blot. Cell viability, apoptosis, migration, and invasion were assessed by CCK-8, flow cytometry, and Transwell. Total N6-methyladenosine (m6A) quantification and its enrichment on SLC7A11 mRNA were determined, followed by the observation of Ki67, ALKBH5 and SLC7A11-positive cell numbers. Glutathione (GSH), lipid reactive oxygen species (lipid-ROS), malondialdehyde (MDA), and iron ion contents were determined. Animal experiments further analyzed the role of ALKBH5 in tumor development and glutathione peroxidase 4 (GPX4) expression.

RESULTS

Bioinformatics analysis revealed the lowly-expressed ALKBH5 in LC patients. ALKBH5 was downregulated in NSCLC cells and its upregulation repressed proliferation activity, invasion, and migration, and facilitated apoptosis. ALKBH5 upregulation decreased GSH, increased lipid-ROS, MDA, and iron ion contents, and downregulated SLC7A11 by reducing m6A modification. SLC7A11 upregulation partly annulled the effect of ALKBH5 overexpression on cell ferroptosis and malignant behaviors. In vivo assays elucidated the suppression of ALKBH5 upregulation on tumor development and GPX4 levels.

CONCLUSION

ALKBH5 upregulation downregulates SLC7A11 transcription by decreasing m6A modification, thus promoting NSCLC cell ferroptosis and ultimately repressing NSCLC progression.