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.

Kinesin Family Member C1 Overexpression Exerts Tumor-Promoting Properties in Head and Neck Squamous Cell Carcinoma via the Rac1/Wnt/ß-catenin Pathway.

Kinesin family member C1 (KIFC1) is a kinesin-14 motor protein, and its abnormal upregulation promotes the malignant behavior of cancer cells. N6-methyladenosine (m6A) RNA methylation is a common modification of eukaryotic messenger RNA and affects RNA expression. In this study, we explored how KIFC1 regulated head and neck squamous cell carcinoma (HNSCC) tumorigenesis and how m6A modification affected KIFC1 expression. A bioinformatics analysis was performed to screen for genes of interest, and in vitro and in vivo studies were carried out to investigate the function and mechanism of KIFC1 in HNSCC tissues. We observed that the expression of KIFC1 in HNSCC tissues was significantly higher than that in normal or adjacent normal tissues. Patients with cancer with higher KIFC1 expression have a lower tumor differentiation status. Demethylase alkB homolog 5, a cancer-promoting factor in HNSCC tissues, could interact with KIFC1 messenger RNA and posttranscriptionally activate KIFC1 through m6A modification. KIFC1 downregulation suppressed HNSCC cell growth and metastasis in vivo and in vitro. However, overexpression of KIFC1 promoted these malignant behaviors. We demonstrated that KIFC1 overexpression activated the oncogenic Wnt/ß-catenin pathway. KIFC1 interacted with the small GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1) at the protein level and increased its activity. The Rho GTPase Rac1 was indicated to be an upstream activator of the Wnt/ß-catenin signaling pathway, and its Rac1 inhibitor, NSC-23766, treatment reversed the effects caused by KIFC1 overexpression. Those observations demonstrate that abnormal expression of KIFC1 may be regulated by demethylase alkB homolog 5 in an m6A-dependent manner and promote HNSCC progression via the Rac1/Wnt/ß-catenin pathway.

MiR-141-3p promotes malignant progression in prostate cancer through AlkB homolog 5-mediated m6A modification of protein arginine methyltransferase 6.

Prostate cancer (PCa) is one of the leading causes of cancer-related death in males worldwide and exploring more reliable biomarkers for PCa is essential for the diagnosis and therapeutics for the disease. Although the functions of miR-141-3p and AlkB homolog 5 (ALKBH5) were identified in some cancers, whether they were involved in the development of PCa remains unclear. In this study, reverse transcription-quantitative polymerase chain reaction unveiled that the expression of ALKBH5 was reduced in PCa tissues and was negatively correlated with miR-141-3p. ALKBH5 attenuated the malignant development of PCa through suppressing the growth, migration, invasion, and sphere formation abilities of PCa cells. In addition, the luciferase activity assay identified that ALKBH5 was corroborated as a downstream target of miR-141-3p. Moreover, miR-141-3p expression was boosted in PCa tissues and cells and inhibition of miR-141-3p suppressed the tumor growth of PCa in vivo. Moreover, ALKBH5 was confirmed to suppress protein arginine methyltransferase 6 (PRMT6) expression through N6-methyladenosine (m6A) modification. We further identified that miR-141-3p-modulated PRMT6 level through mediating ALKBH5. Furthermore, PRMT6 level was positively correlated with miR-141-3p level and negatively associated with ALKBH5 level. Finally, rescue assays also uncovered that miR-141-3p aggravated PCa development by regulating PRMT6. In conclusion, miR-141-3p accelerated the malignant progression of PCa through ALKBH5-mediated m6A modification of PRMT6, which might offer a novel insight into the role of miR-141-3p and ALKBH5 in the treatments of PCa patients.

Promotion of the resistance of human oral epithelial cells to herpes simplex virus type I infection via N6-methyladenosine modification.

OBJECTIVE: This study aimed to explore the mechanism behind N6-methyladenosine (m6A) modification of the total ribonucleic acid (RNA) involved in the resistance to herpes simplex virus type I (HSV-1) infection in oral epithelial cells. METHOD: The variation in m6A modification level on messenger RNA following HSV-1 infection was determined using the RNA dot blot method. The expression levels of alpha-ketoglutarate-dependent dioxygenase lab homolog 5 (ALKBH5) protein and fatty mass and obesity-associated genes (FTO) were determined using real-time fluorescence quantification polymerase chain reaction and the western blot technique, respectively. Next, after suppressing the expression of ALKBH5 or FTO via small interfering RNA, human immortalised oral epithelial cells (HIOECs) were infected with HSV-1, followed by measurement of the viral load or expression level of type I interferon (I-IFN) and interferon-stimulated genes (ISGs). RESULTS: The m6A modification level was significantly increased following HSV-1 infection of the HIOECs (P < 0.05), while the expression of ALKBH5 and FTO genes was reduced (P < 0.01). Moreover, the suppression of ALKBH5 or FTO increased the production of I-IFN and ISGs during the HSV-1 infection of the HIOECs (P < 0.01), and the viral load was significantly reduced (P < 0.01). CONCLUSION: During oral HSV-1 infection, the m6A level was increased through the down-regulation of ALBHK5 and FTO expression, increasing I-IFN production and the promotion of HSV-1 clearing in HIOECs.

MiR-654-3p, reduced by the excessive ALKBH5, Alleviated the Inflammation in OA by targeting TNFRSF9, the trigger of the NF-κB pathway.

MicroRNA (miRNA) is one of the most potent therapeutic targets for osteoarthritis (OA). We identified that miR-654-3p protected the phenotype of chondrocytes. We demonstrated that TNF receptor superfamily member 9 (TNFRSF9) was the target of miR-654-3p by binding to its 3'UTR regions, based on a dual-luciferase reporter assay and an RNA binding protein immunoprecipitation (RIP) assay. In addition, further experiments proved that TNFRSF9, as a trigger of the NF-κB pathway, correlated with the inflammation in chondrocytes. MiR-654-3p overexpressed in the knee of mice alleviated the OA in vivo. Moreover, we examined the m6A enzyme level in OA, proving that the abnormal expression of α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) contributed to the miR-654-3p decrease. Our research illustrated the significant role of miR-654-3p in OA, including its maturation and the mechanism in protecting the phenotype of chondrocytes, which could be a new treatment target for OA.

KDM4C represses liver fibrosis by regulating H3K9me3 methylation of ALKBH5 and m6A methylation of snail1 mRNA.

OBJECTIVE: We aimed to disclose the molecular mechanism of snail1 in liver fibrosis. METHODS: Carbon tetrachloride (CCl4) was used to induce a liver fibrosis model in mice whereby serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated, and liver pathological alternations were assessed. Rat hepatic stellate cells (HSC-T6) were irritated with transforming growth factor (TGF)-ß1, followed by assessment of cell viability and migration. The levels of snail1, ALKBH5, and lysine specific demethylase 4C (KDM4C) were quantified by immunohistochemistry, western blot, or reverse transcription-quantitative polymerase chain reaction, in addition to α-smooth muscle actin (SMA), anti-collagen type I α1 (COL1A1), vimentin, and E-cadherin. Photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation and RNA stability were evaluated to determine the relationship between ALKBH5 and snail1. Changes in KDM4C-bound ALKBH5 promoter and enrichment of histone H3 lysine 9 trimethylation (H3K9me3) at the ALKBH5 promoter were determined using chromatin immunoprecipitation. RESULTS: In fibrosis mice, snail1 was upregulated while ALKBH5 and KDM4C were downregulated. KDM4C overexpression reduced serum ALT and AST levels, liver injury, and α-SMA, COL1A1 and VIMENTIN expressions but increased E-cadherin expression. However, the aforementioned trends were reversed by concurrent overexpression of snail1. In HSC-T6 cells exposed to TGF-ß1, ALKBH5 overexpression weakened cell viability and migration, downregulated α-SMA, COL1A1 and VIMENTIN, upregulated E-CADHERIN, and decreased m6A modification of snail1 and its mRNA stability. KDM4C increased ALKBH5 expression by lowering H3K9me3 level, but inhibited HSC-T6 cell activation by regulating the ALKBH5/snail1 axis. CONCLUSION: KDM4C decreases H3K9me3 methylation to upregulate ALKBH5 and subsequently inhibits snail1, ultimately impeding liver fibrosis.

ALKBH5 deficiency attenuates oxygen-glucose deprivation-induced injury in mouse brain microvascular endothelial cells in an m6A dependent manner.

Structural and functional alterations in brain microvascular endothelial cells (BMECs) caused by oxygen-glucose deprivation (OGD) are involved in the pathogenesis of various brain disorders. AlkB homolog 5 (ALKBH5) is a primary m6A demethylase that regulates various cell processes, but its distinct roles in BMEC function remain to be clarified. In the present study, in mouse middle cerebral artery occlusion (MCAO) model, knockout of ALKBH5 reduced neurological deficits, infarct volumes and tissue apoptosis caused by ischemia/reperfusion injury. Evans blue leakage and decreased expression of the tight junction protein ZO-1 and Occludin were also attenuated by ALKBH5 knockout. During the exploration of the underlying mechanisms of the role of ALKBH5 in BMECs, we found that the expression of ALKBH5 was induced at both the mRNA and protein levels by hypoxia; however, its protein stability was impaired by OGD treatment. Knockdown of ALKBH5 expression increased total m6A levels and alleviated OGD-induced BMEC injury. At the same time, the selective ALKBH5 inhibitor Cpd 20m also exhibited a protective effect on cell injury. In contrast, overexpression of ALKBH5 increased the sensitivity of BMECs to OGD. Interestingly, the m6A sequencing data revealed that knockdown of ALKBH5altered the expression of many genes via m6A upregulation. The gene expression alterations were verified by real-time PCR. Taken together, our results suggest that ALKBH5, as well as its target genes, plays important roles in the regulation of brain microvascular endothelial cell function through its RNA demethylase activity.

ALKBH5 inhibitors as a potential treatment strategy in heart failure-inferences from gene expression profiling.

Heart Failure (HF) is a complex clinical syndrome in which the heart is unable to provide enough blood flow to meet metabolic needs and lacks efficient venous return. HF is a major risk factor for morbidity and mortality with cardiovascular diseases globally. Despite enormous research, the molecular markers relevant to disease prognosis and management remain not well understood. Here, we analyzed the whole transcriptomes of 18 failing hearts and 15 non-failing hearts (predominantly of Caucasian origin), by applying the standard in silico tools. The analyses revealed novel gene-markers including ALKBH5 of mRNA demethylation and KMT2E of histone modification processes, significantly over-expressed in the HF compared with the non-failing hearts (FDR < 0.05). To validate the over-expression of ALKBH5, we determined the global m6A level in hypoxic H9c2 cells using a dot blot assay. The global m6A level was found markedly lower in the hypoxic H9c2 cells than in the control cells. Additionally, the expression of ALKBH5 in the H9c2 cells was quantified by the qPCR and found to be 1.18 times higher at 12 h (p < 0.05), and 1.67 times higher at 24 h of hypoxia (p < 0.01) compared with the control cells, indicating a likely role of ALKBH5 in the failing cardiac cells. Furthermore, we identified several compounds through the virtual screening of 11,272 drug-like molecules of the ZINC15 database to inhibit the ALKBH5 in a molecular docking process. Collectively, the study revealed novel markers potentially involved in the pathophysiology of HF and suggested plausible therapeutic molecules for the management of the disease.

Tanshinone IIA alleviates cardiac hypertrophy through m6A modification of galectin-3.

Cardiac hypertrophy results from the adaptive response of the myocardium to pressure overload on the heart. Tanshinone IIA (Tan IIA) is the major active compound extracted from Salvia miltiorrhiza Bunge, which possesses various pharmacological benefits. In the present study, the effect and mechanism of action of Tan IIA on cardiac hypertrophy were studied. Ang II-induced and transverse aortic constriction (TAC)-induced cardiomyocyte hypertrophy models were used to evaluate the effect of Tan IIA. An adenoviral vector system was utilized to overexpress galectin-3. The results revealed that Tan IIA significantly inhibited Ang II-induced hypertrophy in vitro and TAC-induced cardiac hypertrophy in vivo. Furthermore, Tan IIA notably inhibited the expression of galectin-3. Rescue experiments indicated that galectin-3 overexpression reversed the effects of Tan IIA, which further validated the interaction between Tan IIA and galectin-3. Additionally, Tan IIA suppressed alkB homolog 5, RNA demethylase (ALKBH5)-mediated N6-methyladenosine (m6A) modification of galectin-3. In summary, the results of the present study indicated that Tan IIA attenuates cardiac hypertrophy by targeting galectin-3, suggesting that galectin-3 plays a critical role in cardiac hypertrophy and represents a new therapeutic target.

Downregulated ALKBH5 contributes to myocardial ischemia/reperfusion injury by increasing m6A modification of Trio mRNA.

Background: The modification of N6-methyladenosine (m6A) is a dynamic and reversible course that might play a role in cardiovascular disease. However, the mechanisms of m6A modification in myocardial ischemia/reperfusion injury (MIRI) remain unclear. Methods: A mouse model of MIRI and a cell model of oxygen-glucose deprivation/reperfusion (OGD/R) HL-1 cells were employed. In an in vivo study, the total RNA m6A modification levels were determined by dot blot, and the key genes related to m6A modification were screened by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot. In an in vitro study, the effects of AlkB homolog 5 (ALKBH5), an RNA demethylase, on cell proliferation, cell injury, and apoptosis were detected by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay, lactate dehydrogenase (LDH) and cardiac troponin-I (cTnI) levels, and flow cytometry. Besides, the m6A modification-changed and differentially expressed messenger RNA (mRNA) were determined by methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) in ALKBH5-overexpressed HL-1 cells. Finally, the mRNA levels of the promising targeted gene were examined by RT-qPCR and its m6A modification levels were examined by MeRIP-qPCR. Results: Our results showed that RNA m6A modification was involved in MIRI, in which ALKBH5 was downregulated. Functionally, by overexpressing or silencing ALKBH5 in experimental cells, we verified its protective properties on cell proliferation, cell injury, and apoptosis in the process of MIRI. Besides, we provided a mass of latent different mRNAs with m6A modification variation in ALKBH5-overexpressed HL-1 cells. Mechanistically, we further screened the most potential targeted mRNAs and suggested that triple functional domain (Trio) mRNA could be upregulated by ALKBH5 by reducing m6A level of Trio. Conclusions: This study demonstrated that the downregulated ALKBH5 might contribute to MIRI process by increasing the m6A modification of Trio mRNA and downregulating Trio.

Discovery of two novel ALKBH5 selective inhibitors that exhibit uncompetitive or competitive type and suppress the growth activity of glioblastoma multiforme.

A group of RNA methylation enzymes is currently of interest as a new target for cancer therapy. Alpha-ketoglutarate-dependent dioxygenase B (AlkB) homolog 5 (ALKBH5) is an N6 -methyladenosine (m6 A) demethylation enzyme, and by high-throughput screening from pure small molecule compounds, we identified two novel inhibitors, Ena15 and Ena21, against it. Each compound showed either uncompetitive or competitive inhibition for 2-oxoglutarate (2OG). In addition, Ena21 had little inhibitory activity for fat mass and obesity-associated protein (FTO), which is another N6 -methyladenosine demethylation enzyme, while Ena15 enhanced the demethylase activity of FTO. The predicted binding poses of both compounds with the crystal structure of ALKBH5 (PDB ID: 4NRO) were comparable with these observations pertaining to the interaction of the 2OG catalytic site in this enzyme kinetics. Furthermore, either knockdown of ALKBH5 or inhibition with Ena15 or Ena21 inhibited cell proliferation of glioblastoma multiforme-derived cell lines, decreased cell population in the synthesis phase of the cell cycle, increased m6 A RNA level, and stabilized FOXM1 mRNA. Based on these results, Ena15 and Ena21 were found to be potential candidates that might help in further research into the biological function of ALKBH5.

IGF2BP3 is an essential N6-methyladenosine biotarget for suppressing ferroptosis in lung adenocarcinoma cells.

A lack of promising targets leads to poor prognosis in patients with lung adenocarcinoma (LUAD). Therefore, it is urgent to identify novel therapeutic targets. The importance of the N6-methyladenosine (m6A) RNA modification has been demonstrated in various types of tumors; however, knowledge of m6A-related proteins in LUAD is still limited. Here, we found that insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3), an m6A reader protein, is highly expressed in LUAD and associated with poor prognosis. IGF2BP3 desensitizes ferroptosis (a new form of regulated cell death) in a manner dependent on its m6A reading domain and binding capacity to m6A-methylated mRNAs encoding anti-ferroptotic factors, including but not limited to glutathione peroxidase 4 (GPX4), solute carrier family 3 member 2 (SLC3A2), acyl-CoA synthetase long chain family member 3 (ACSL3), and ferritin heavy chain 1 (FTH1). After IGF2BP3 overexpression, expression levels and mRNA stabilities of these anti-ferroptotic factors were successfully sustained. Notably, significant correlations between SLC3A2, ACSL3, and IGF2BP3 were revealed in clinical LUAD specimens, further establishing the essential role of IGF2BP3 in desensitizing ferroptosis. Inducing ferroptosis has been gradually accepted as an alternative strategy to treat tumors. Thus, IGF2BP3 could be a potential target for the future development of new biomaterial-associated therapeutic anti-tumor drugs.

Loss of m6A demethylase ALKBH5 promotes post-ischemic angiogenesis via post-transcriptional stabilization of WNT5A.

BACKGROUND: Post-ischemic angiogenesis is critical for blood flow recovery and ischemic tissue repair. N6-methyladenosine (m6A) plays essential roles in numerous biological processes. However, the impact and connected mechanism of m6A on post-ischemic angiogenesis are not fully understood. METHODS: AlkB homolog 5 (ALKBH5) was screened out among several methyltransferases and demethylases involved in dynamic m6A regulation. Cardiac microvascular endothelial cells (CMECs) angiogenesis and WNT family member 5A (WNT5A) stability were analyzed upon ALKBH5 overexpression with adenovirus or knockdown with small interfering RNAs in vitro. The blood flow recovery, capillary, and small artery densities were evaluated in adeno-associated virus (AAV)-ALKBH5 overexpression or ALKBH5 knockout (KO) mice in a hind-limb ischemia model. The same experiments were conducted to explore the translational value of transient silencing of ALKBH5 with adenovirus. RESULTS: ALKBH5 was significantly upregulated in hypoxic CMECs and led to a global decrease of m6A level. ALKBH5 overexpression further reduced m6A level in normoxic and hypoxic CMECs, impaired proliferation, migration, and tube formation only in hypoxic CMECs. Conversely, ALKBH5 knockdown preserved m6A levels and promoted angiogenic phenotypes in hypoxic but not in normoxic CMECs. Mechanistically, ALKBH5 regulated WNT5A expression through post-transcriptional mRNA modulation in an m6A-dependent manner, which decreased its stability and subsequently impeded angiogenesis in hypoxic CMECs. Furthermore, ALKBH5 overexpression hindered blood flow recovery and reduced CD31 and alpha-smooth muscle actin expression in hind-limb ischemia mice. As expected, ALKBH5-KO mice exhibited improved blood flow recovery, increased capillary, and small artery densities after hind-limb ischemia, and similar beneficial effects were observed in mice with transient adenoviral ALKBH5 gene silencing. CONCLUSION: We demonstrate that ALKBH5 is a negative regulator of post-ischemic angiogenesis via post-transcriptional modulation and destabilization of WNT5A mRNA in an m6A-dependent manner. Targeting ALKBH5 may be a potential therapeutic option for ischemic diseases, including peripheral artery disease.

Changes in m6A demethylase ALKBH5 expression in form-deprivation myopic guinea pigs and its significance / 中华实验眼科杂志

Objective:To investigate the alteration of m6A demethylase AlkB homolog 5 (ALKBH5) expression and its impact on form-deprivation myopia (FDM) retina in guinea pigs.Methods:Thirty normal SPF grade 3-week-old tricolor guinea pigs were randomly divided into normal control group and experimental group, with 15 in each group.In the experimental group, the right eyes were covered as FDM group and the left eyes uncovered were set as self-control group.Ocular biometry was performed at one-week intervals from baseline to week 4 of the experiment.Spherical equivalent was detected by streak retinoscopy and axial length was measured by A-scan ultrasonography.Animals were sacrificed after 4 weeks of modeling.The distribution and expression of ALKBH5 protein in the guinea pig retina was detected by immunohistochemical and immunofluorescence staining.Expression of ALKBH5 mRNA and protein in guinea pig retina was detected by real-time fluorescence quantitative PCR and Western blot, respectively.The use of animals in ophthalmic and vision research followed the tenets of Animal Research in Vision and Ophthalmology, and the study was approved by the Ethics Committee of North Sichuan Medical College (No.2023087).Results:At weeks 2, 3, and 4 after myopia induction, diopters and axial lengths were significantly higher in the FDM group than in the normal control group and the self-control group (all at P<0.001). Immunohistochemistry and immunofluorescence assays showed that ALKBH5 protein was expressed in the retinal nerve fiber layer, rod/cone photoreceptor cells, and retinal pigment epithelium (RPE) layer, and was highly expressed in the retinal nerve fiber layer and RPE layer.The relative ALKBH5 immunofluorescence intensity in the normal control group, self-control group and FDM group was 1.000±0.204, 0.874±0.076 and 0.571±0.053, respectively, which was lower in the FDM group than in the normal control and self-control groups, showing statistically significant differences ( t=4.069, P=0.006; t=5.176, P=0.014). After 4 weeks of modeling, ALKBH5 mRNA and protein expressions were significantly lower in FDM group than in normal control and self-control groups (both at P<0.01). Conclusions:The expression of m6A demethylase ALKBH5 is decreased in the retina of FDM guinea pigs, suggesting that ALKBH5 and related m6A methylation modification may be involved in the development and progression of myopia.

Progress of research on m6A demethylases in gastric cancer / 上海交通大学学报（医学版）

Gastric cancer(GC)is one of the most common malignancies in the digestive system.Many patients are found in advanced stage and have a poor prognosis.Surgery and chemotherapy remain the main treatments for gastric cancer.N6-methyladenosine(m6A)is a hot topic in tumor research in recent years.As the most common form of RNA modification in eukaryotes,m6A can regulate various stages of the RNA cycle,including RNA splicing,processing,degradation,and translation,thereby regulating RNA expression and function,playing a critical role in various pathways such as cell differentiation,development,and metabolism.The m6A demethylase can remove methyl groups on RNA,ensuring that m6A methylation is a dynamic and reversible process.As a key enzyme in the m6A methylation process,the imbalance of m6A demethylases fat mass and obesity-associated protein(FTO),AlkB homolog 5(ALKBH5)and ALKBH3 regulate the progression of gastric cancer through various mechanisms,which is closely related to the occurrence and development of gastric cancer.These m6A demethylases regulate the signaling pathway,alter the proliferation and invasion ability of gastric cancer cells,affect its resistance to chemotherapy drugs,participate in regulating the immune response and mitochondrial metabolism of gastric cancer,and affect the growth of gastric cancer cells.They are expected to become a novel therapeutic target.This article comprehensively summarizes the molecular mechanism of m6A demethylase involved in the occurrence and development of gastric cancer,and the relationship between its expression and function,and biological characteristics of m6A demethylase were reviewed,aiming to provide new research ideas for early diagnosis and targeted treatment of gastric cancer.