The RNA m(6)A writer WTAP in diseases: structure, roles, and mechanisms

Molecular mechanism of Wilms tumour 1-associated protein in diabetes-related dry eye disease by mediating m6A methylation modification of lncRNA NEAT1

Background: Dry eye disease (DED) is often secondary to diabetes mellitus (DM).Purpose: This study is to explore the action of Wilms tumor 1-associated protein (WTAP) in DM-DED via lncRNA NEAT1 m6A methylation.Methods: DM-DED mouse models were treated with sh-WTAP/sh-NEAT1, followed by assessment of corneal epithelial damage/histopathological changes. HCE-2 cells were exposed to hyperosmotic conditions to establish in vitro DED models and treated with oe-NEAT1/sh-NEAT1/sh-WTAP/nigericin (an NLRP3 inflammasome inducer). Cell viability/apoptosis were evaluated by CCK-8/TUNEL. Levels of WTAP/NEAT1/inflammatory factors/NLRP3 inflammasome- and apoptosis-related markers were determined. m6A modification was examined by MeRIP-qPCR and NEAT1 stability was also detected.Results: DM-DED mice exhibited up-regulated WTAP/NEAT1 expression and severe corneal damage, whereas WTAP/NEAT1 knockdown alleviated inflammation/corneal damage. In hyperosmolarity-induced HCE-2 cells, NEAT1 aggravated inflammation and apoptosis, while NEAT1 knockdown suppressed NLRP3 inflammasome activation and ameliorated cell injury. Hyperosmolarity-induced WTAP expression increased m6A modification and NEAT1 mRNA stability. WTAP mediated m6A methylation of NEAT1 and NLRP3 inflammasome activation in DM-DED mice.

Recent advances in the reciprocal regulation of m6A modification with non-coding RNAs and its therapeutic application in acute myeloid leukemia

N6-methyladenosine (m6A) is one of the most common modifications of RNA in eukaryotic cells and is involved in mRNA metabolism, including stability, translation, maturation, splicing, and export. m6A also participates in the modification of multiple types of non-coding RNAs, such as microRNAs, long non-coding RNAs, and circular RNAs, thereby affecting their metabolism and functions. Increasing evidence has revealed that m6A regulators, such as writers, erasers, and readers, perform m6A-dependent modification of ncRNAs, thus affecting cancer progression. Moreover, ncRNAs modulate m6A regulators to affect cancer development and progression. In this review, we summarize recent advances in understanding m6A modification and ncRNAs and provide insights into the interaction between m6A modification and ncRNAs in cancer. We also discuss the potential clinical applications of the mechanisms underlying the interplay between m6A modifications and ncRNAs in acute myeloid leukemia (AML). Therefore, clarifying the mutual regulation between m6A modifications and ncRNAs is of great significance to identify novel therapeutic targets for AML and has great clinical application prospects.

N6-methyladenosine (m6A) Writer WTAP Potentiates Hepatocellular Carcinoma Immune Evasion and Aerobic Glycolysis

Hepatocellular carcinoma (HCC) is one of most prevalent malignant tumors with poor prognosis and a high mortality rate. Recent research indicates that N6-methyladenosine (m6A) and tumor immunotherapy are important factors in HCC. More research is still needed to fully understand the profound roles that m6A writer Wilms tumor 1-associated protein (WTAP) and CD8+ T cells play in the antitumor immunity that prevents HCC from progressing. According to the findings of our investigation, WTAP was significantly elevated in HCC cells and was associated with a poor prognosis. Functionally, WTAP accelerated HCC immune evasion and aerobic glycolysis while suppressing the tumor-killing ability of CD8+ T cells. On the other hand, WTAP knockdown had the opposite effect. WTAP targets the m6A site on the 3'-UTR of PD-L1 mRNA, which mechanistically increases the stability of PD-L1 mRNA. These results showed that WTAP inhibited CD8+ T cells' antitumor activity, which in turn deteriorated HCC immune evasion and aerobic glycolysis. In conclusion, our research uncovers a novel mechanism for WTAP on the tumor-killing ability of CD8+ T cells, which helps to overcome HCC immune evasion.

WTAP-induced N6-methyladenosine of PD-L1 blocked T-cell-mediated antitumor activity under hypoxia in colorectal cancer

N6-Methyladenosine (m6A) is a important process regulating gene expression post-transcriptionally. Programmed death ligand 1 (PD-L1) is a major immune inhibitive checkpoint that facilitates immune evasion and is expressed in tumor cells. In this research we discovered that Wilms' tumor 1-associated protein (WTAP) degradation caused by ubiquitin-mediated cleavage in cancer cells (colorectal cancer, CRC) under hypoxia was inhibited by Pumilio homolog 1 (PUM1) directly bound to WTAP. WTAP enhanced PD-L1 expression in a way that was m6A-dependent. m6A "reader," Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) identified methylated PD-L1 transcripts and subsequently fixed its mRNA. Additionally, we found that T-cell proliferation and its cancer cell-killing effects were prevented by overexpression of WTAP in vitro and in vivo. Overexpression prevented T cells from proliferating and killing CRC by maintaining the expression of PD-L1. Further evidence supporting the WTAP-PD-L1 regulatory axis was found in human CRC and organoid tissues. Tumors with high WTAP levels appeared more responsive to anti-PD1 immunotherapy, when analyzing samples from patients undergoing treatment. Overall, our findings demonstrated a novel PD-L1 regulatory mechanism by WTAP-induced mRNA epigenetic regulation and the possible application of targeting WTAP as immunotherapy for tumor hypoxia.

Role of N6‑methyladenosine in the pathogenesis, diagnosis and treatment of prostate cancer (Review)

Prostate cancer (PCa) affects males of all racial and ethnic groups, and leads to higher rates of mortality in those belonging to a lower socioeconomic status due to the late detection of the disease. PCa affects middle‑aged males between the ages of 45 and 60 years, and is the highest cause of cancer‑associated mortality in Western countries. As the most abundant and common mRNA modification in higher eukaryotes, N6‑methyladenosine (m6A) is widely distributed in mammalian cells and influences various aspects of mRNA metabolism. Recent studies have found that abnormal expression levels of various m6A regulators significantly affect the development and progression of various types of cancer, including PCa. The present review discusses the influence of m6A regulatory factors on the pathogenesis and progression of PCa through mRNA modification based on the current state of research on m6A methylation modification in PCa. It is considered that the treatment of PCa with micro‑molecular drugs that target the epigenetics of the m6A regulator to correct abnormal m6A modifications is a direction for future research into current diagnostic and therapeutic approaches for PCa.

RNA methylation: A potential therapeutic target in autoimmune disease

Autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and inflammatory bowel disease (IBD) are caused by the body's immune response to autoantigens. The pathogenesis of autoimmune diseases is unclear. Numerous studies have demonstrated that RNA methylation plays a key role in disease progression, which is essential for post-transcriptional regulation and has gradually become a broad regulatory mechanism that controls gene expression in various physiological processes, including RNA nuclear output, translation, splicing, and noncoding RNA processing. Here, we outline the writers, erasers, and readers of RNA methylation, including N6-methyladenosine (m6A), 2'-O-methylation (Nm), 2'-O-dimethyladenosine (m6Am), N1-methyladenosine (m1A), 5-methylcytidine (m5C) and N7-methylguanosine (m7G). As the role of RNA methylation modifications in the immune system and diseases is explained, the potential treatment value of these modifications has also been demonstrated. This review reports the relationship between RNA methylation and autoimmune diseases, highlighting the need for future research into the therapeutic potential of RNA modifications.

Effects and mechanisms of N6-methyladenosine RNA methylation in environmental pollutant-induced carcinogenesis

Environmental pollution, including air pollution, plastic contamination, and heavy metal exposure, is a pressing global issue. This crisis contributes significantly to pollution-related diseases and is a critical risk factor for chronic health conditions, including cancer. Mounting evidence underscores the pivotal role of N6-methyladenosine (m6A) as a crucial regulatory mechanism in pathological processes and cancer progression. Governed by m6A writers, erasers, and readers, m6A orchestrates alterations in target gene expression, consequently playing a vital role in a spectrum of RNA processes, covering mRNA processing, translation, degradation, splicing, nuclear export, and folding. Thus, there is a growing need to pinpoint specific m6A-regulated targets in environmental pollutant-induced carcinogenesis, an emerging area of research in cancer prevention. This review consolidates the understanding of m6A modification in environmental pollutant-induced tumorigenesis, explicitly examining its implications in lung, skin, and bladder cancer. We also investigate the biological mechanisms that underlie carcinogenesis originating from pollution. Specific m6A methylation pathways, such as the HIF1A/METTL3/IGF2BP3/BIRC5 network, METTL3/YTHDF1-mediated m6A modification of IL 24, METTL3/YTHDF2 dynamically catalyzed m6A modification of AKT1, METTL3-mediated m6A-modified oxidative stress, METTL16-mediated m6A modification, site-specific ATG13 methylation-mediated autophagy, and the role of m6A in up-regulating ribosome biogenesis, all come into play in this intricate process. Furthermore, we discuss the direction regarding the interplay between pollutants and RNA metabolism, particularly in immune response, providing new information on RNA modifications for future exploration.

LncRNA SNHG12 regulated by WTAP aggravated the oxygen-glucose deprivation/reperfusion-induced injury in bEnd.3 cell

OBJECTIVES

Previous studies have identified abnormal expression of lncRNA SNHG12 in ischemic stroke, but the underlying molecular mechanism remains unclear.

MATERIALS AND METHODS

Through database predictions, m6A methylation sites were found on SNHG12, suggesting post-transcriptional modification. To further elucidate the role of SNHG12 and m6A methyltransferase WTAP in oxygen-glucose deprivation/reperfusion (OGD/R)-induced damage in cerebral microvascular endothelial cells, we conducted investigations. Additionally, we examined the impact of m6A methyltransferase WTAP on SNHG12 expression.

RESULTS

Overexpressing SNHG12 in bEnd.3 cells was found to inhibit cell proliferation and promote apoptosis, as well as activate the production of reactive oxygen species and inflammatory cytokines (E-selectin, IL-6 and MCP-1), along with angiogenic proteins (VEGFA and FGFb). Conversely, SNHG12 knockdown alleviated OGD/R-induced damage to BEnd.3 cells, resulting in improved cell proliferation, reduced apoptosis, decreased ROS and LDH production, as well as diminished expression of inflammatory cytokines (E-selectin, IL-6 and MCP-1) and angiogenic proteins (VEGFA and FGFb). Furthermore, WTAP was found to positively regulate SNHG12 expression, and WTAP knockdown in bEnd.3 cells under the OGD/R conditions inhibited cell proliferation, promoted apoptosis, and increased ROS and LDH production.

CONCLUSION

These findings suggest that WTAP may play a crucial role in SNHG12-mediated OGD/R-induced damage in bEnd.3 cells. More molecular experiments are needed to further analyze its mechanism. Overall, our study helps to enrich our understanding of the dysregulation of SNHG12 in ischemic stroke.

EGR1 modulates EPHB4-induced trophoblast dysfunction in recurrent spontaneous abortion†

Recurrent spontaneous abortion, defined as at least three unexplained abortions occurring before the 20-24 week of pregnancy, has a great impact on women's quality of life. Ephrin receptor B4 has been associated with trophoblast function in preeclampsia. The present study aimed to verify the hypothesis that ephrin receptor B4 regulates the biological functions of trophoblasts in recurrent spontaneous abortion and to explore the upstream mechanism. Ephrin receptor B4 was overexpressed in mice with recurrent spontaneous abortion. Moreover, ephrin receptor B4 inhibited trophoblast proliferation, migration, and invasion while promoting apoptosis. Downregulation of early growth response protein 1 expression in mice with recurrent spontaneous abortion led to ephrin receptor B4 overexpression. Poor expression of WT1-associated protein in mice with recurrent spontaneous abortion reduced the modification of early growth response protein 1 mRNA methylation, resulting in decreased early growth response protein 1 mRNA stability and expression. Overexpression of WT1-associated protein reduced the incidence of recurrent spontaneous abortion in mice by controlling the phenotype of trophoblasts, which was reversed by early growth response protein 1 knockdown. All in all, our findings demonstrate that dysregulation of WT1-associated protein contributes to the instability of early growth response protein 1, thereby activating ephrin receptor B4-induced trophoblast dysfunction in recurrent spontaneous abortion. Our study provides novel insights into understanding the molecular pathogenesis of recurrent spontaneous abortion.

The m6A reader IGF2BP1 attenuates the stability of RPL36 and cell proliferation to mediate benzene hematotoxicity by recognizing m6A modification

Benzene exposure leads to hematotoxicity, and epigenetic modification is considered to be a potential mechanism of benzene pathogenesis. As a newly discovered post-transcriptional modification, the roles of N6-methyladenosine (m6A) in benzene hematotoxicity are still unclear. m6A can only exert its gene regulatory function after being recognized by m6A reading proteins. In this study, we found that the expression of m6A reader IGF2BP1 decreased in benzene poisoning workers and in 20 μM benzene metabolite 1,4-BQ-treated AHH-1 cells. Further overexpression of IGF2BP1 in mice alleviated 50 ppm benzene-induced hematopoietic damage, suggesting that IGF2BP1 plays a critical role in benzene hematotoxicity. Next, we examined transcriptome-wide m6A methylation in vitro to search for target genes of IGF2BP1. We found that benzene metabolite 1,4-BQ treatment altered the m6A methylation levels of various genes. The comprehensive analysis of mRNA expression and m6A methylation uncovered that the hypomethylated Ribosomal Protein L36 (RPL36) and its consequent reduced expression impaired cell proliferation. Mechanically, m6A modification reduced RNA stability to down-regulate RPL36 expression. Moreover, overexpression of IGF2BP1 relieved RPL36 reduction and cell proliferation inhibition caused by benzene in vitro and in vivo by directly binding with RPL36 mRNA. In conclusion, the m6A reader IGF2BP1 attenuates the stability of RPL36 and cell proliferation to mediate benzene hematotoxicity by recognizing m6A modification. IGF2BP1 and RPL36 may be key molecules and potential therapeutic targets for benzene hematotoxicity.

Transcriptome-wide profiling identifies colon cancer-associated m6A transcripts and potential RNA methyl modifiers

BACKGROUND

N6-methyladenosine (m6A) is a prevalent and crucial RNA methylation modification that plays a significant role in various biological and pathological processes. The dysregulation of m6A has been linked to the initiation, progression, and metastasis of several cancer types, including colon cancer. The transcriptome of colon cancer indeed provides insight into dysregulated coding and non-coding RNAs, but it does not reveal the mechanisms, such as m6A modifications, that determine post-transcriptional and pre-translational regulations. This study using MeRIP sequencing aims to explain the distribution of m6A modification across altered gene expression and its association with colon cancer.

METHODS AND RESULTS

The levels of m6A in different colon cancer cell lines were quantified and correlated with the expression of m6A modifiers such as writers, readers, and erasers. Our results showed that global m6A levels in colon cancer were associated with METTL14, YTHDF2, and YTHDC1. We performed Epi-transcriptome profiling of m6A in colon cancer cell lines using Methylated RNA Immunoprecipitation (MeRIP) sequencing. The differential methylation analysis revealed 7312 m6A regions among the colon cancer cell lines. Our findings indicated that the m6A RNA methylation modifications were mainly distributed in the last exonic and 3' untranslated regions. We also discovered that non-coding RNAs such as miRNA, lncRNA, and circRNA carry m6A marks. Gene set enrichment and motif analysis suggested a strong association of m6A with post-transcriptional events, particularly splicing control. Overall, our study sheds light on the potential role of m6A in colon cancer and highlights the importance of further investigation in this area.

CONCLUSION

This study reports m6A enrichment in the last exonic regions and 3' UTRs of mRNA transcripts in colon cancer. METTL14, YTHDF2, and YTHDC1 were the most significant modifiers in colon cancer cells. The functions of m6A-modified genes were found to be RNA methylation and RNA capping. Overall, the study illustrates the transcriptome-wide distribution of m6A and its eminent role in mRNA splicing and translation control of colon cancer.

The role of N6-methyladenosine in macrophage polarization: A novel treatment strategy for non-alcoholic steatohepatitis

RNA methylation modifications, as a widespread type of modification in eukaryotic cells, especially N6-methyladenosine (m6A), are associated with many activities in organisms, including macrophage polarization and progression of non-alcoholic steatohepatitis (NASH). Macrophages in the liver are of diverse origin and complex phenotype, exhibiting different functions in development of NASH. In the review, we discuss the functions of m6A and m6A-related enzymes in macrophage polarization. Furthermore, we retrospect the role of macrophage polarization in NASH. Finally, we discuss the prospects of m6A in macrophages and NASH, and provide guidance for the treatment of NASH.

Exploring N6-methyladenosine (m6A) modification in tree species: opportunities and challenges

N 6-methyladenosine (m6A) in eukaryotes is the most common and widespread internal modification in mRNA. The modification regulates mRNA stability, translation efficiency, and splicing, thereby fine-tuning gene regulation. In plants, m6A is dynamic and critical for various growth stages, embryonic development, morphogenesis, flowering, stress response, crop yield, and biomass. Although recent high-throughput sequencing approaches have enabled the rapid identification of m6A modification sites, the site-specific mechanism of this modification remains unclear in trees. In this review, we discuss the functional significance of m6A in trees under different stress conditions and discuss recent advancements in the quantification of m6A. Quantitative and functional insights into the dynamic aspect of m6A modification could assist researchers in engineering tree crops for better productivity and resistance to various stress conditions.

Epigenetic modification of m6A methylation: Regulatory factors, functions and mechanism in inflammatory bowel disease

Although the exact cause of inflammatory bowel disease (IBD) is still unknown, there is a lot of evidence to support the notion that it results from a combination of environmental factors, immune system issues, gut microbial changes, and genetic susceptibility. In recent years, the role of epigenetics in the pathogenesis of IBD has drawn increasing attention. The regulation of IBD-related immunity, the preservation of the intestinal epithelial barrier, and autophagy are all significantly influenced by epigenetic factors. The most extensive epigenetic methylation modification of mammalian mRNA among them is N6-methyladenosine (m6A). It summarizes the general structure and function of the m6A regulating factors, as well as their complex effects on IBD by regulating the intestinal mucous barrier, intestine mucosal immunity, epidermal cell death, and intestinal microorganisms.This paper provides key insights for the future identification of potential new targets for the diagnosis and treatment of IBD.

The Functions of N6-Methyladenosine in Nuclear RNAs

N6-methyladenosine (m6A) is one of the most common modifications in both eukaryotic and prokaryotic mRNAs. It has been experimentally confirmed that m6A methylation is involved in the regulation of stability and translation of various mRNAs. Until recently, the majority of m6A-related studies have been focused on the cytoplasmic functions of this modification. Here, we review new data on the role of m6A in several key biological processes taking place in the cell nucleus, such as transcription, chromatin organization, splicing, nuclear-cytoplasmic transport, and R-loop metabolism. Based on analysis of these data, we suggest that m6A methylation of nuclear RNAs is another level of gene expression regulation which, together with DNA methylation and histone modifications, controls chromatin structure and functioning in various biological contexts.

m6A methylation modification and immune cell infiltration: implications for targeting the catalytic subunit m6A-METTL complex in gastrointestinal cancer immunotherapy

N6-methyladenosine (m6A) methylation modification is a ubiquitous RNA modification involved in the regulation of various cellular processes, including regulation of RNA stability, metabolism, splicing and translation. Gastrointestinal (GI) cancers are some of the world's most common and fatal cancers. Emerging evidence has shown that m6A modification is dynamically regulated by a complex network of enzymes and that the catalytic subunit m6A-METTL complex (MAC)-METTL3/14, a core component of m6A methyltransferases, participates in the development and progression of GI cancers. Furthermore, it has been shown that METTL3/14 modulates immune cell infiltration in an m6A-dependent manner in TIME (Tumor immune microenvironment), thereby altering the response of cancer cells to ICIs (Immune checkpoint inhibitors). Immunotherapy has emerged as a promising approach for treating GI cancers. Moreover, targeting the expression of METTL3/14 and its downstream genes may improve patient response to immunotherapy. Therefore, understanding the role of MAC in the pathogenesis of GI cancers and its impact on immune cell infiltration may provide new insights into the development of effective therapeutic strategies for GI cancers.

Up-regulation of RNA m6A methyltransferase like-3 expression contributes to arsenic and benzo[a]pyrene co-exposure-induced cancer stem cell-like property and tumorigenesis

While arsenic or BaP alone exposure can cause lung cancer, studies showed that arsenic plus BaP co-exposure displays a significantly stronger lung tumorigenic effect. However, the underlying mechanism has not been well understood. Studies showed that RNA molecules are chemically modified. The most frequently occurring RNA modification in eukaryotic messenger RNAs is the N6-methyladenosine (m6A) methylation. This study aimed to determine whether arsenic plus BaP exposure alters RNA m6A methylation and its role in lung tumorigenic effect of arsenic plus BaP exposure. Human bronchial epithelial cells transformed by exposure to arsenic or BaP alone, and arsenic plus BaP and mouse xenograft tumorigenesis models were used in this study. It was found that arsenic plus BaP exposure-transformed cells have significantly higher levels of RNA m6A methylation than arsenic or BaP alone exposure-transformed human bronchial epithelial cells. Western blot analysis showed that arsenic plus BaP exposure greatly up-regulates the m6A writer methyltransferase like-3 (METTL3) expression levels in cultured cells and mouse lung tissues. METTL3 knockdown in cells transformed by arsenic plus BaP exposure drastically reduced their RNA m6A methylation levels. Functional studies revealed that METTL3 knockdown in cells transformed by arsenic plus BaP exposure greatly reduces their anchorage-dependent and -independent growth, cancer stem cell characters and tumorigenesis. The findings from this study suggest that arsenic plus BaP co-exposure causes epitranscriptomic dysregulation, which may contribute significantly to arsenic plus BaP co-exposure-caused synergistic lung tumorigenic effect.

N6-methyladenosine methylation in kidney injury

Multiple mechanisms are involved in kidney damage, among which the role of epigenetic modifications in the occurrence and development of kidney diseases is constantly being revealed. However, N6-methyladenosine (M6A), a well-known post-transcriptional modification, has been regarded as the most prevalent epigenetic modifications in higher eukaryotic, which is involved in various biological processes of cells such as maintaining the stability of mRNA. The role of M6A modification in the mechanism of kidney damage has attracted widespread attention. In this review, we mainly summarize the role of M6A modification in the progression of kidney diseases from the following aspects: the regulatory pattern of N6-methyladenosine, the critical roles of N6-methyladenosine in chronic kidney disease, acute kidney injury and renal cell carcinoma, and then reveal its potential significance in the diagnosis and treatment of various kidney diseases. A better understanding of this field will be helpful for future research and clinical treatment of kidney diseases.

AZGP1P2/UBA1/RBM15 Cascade Mediates the Fate Determinations of Prostate Cancer Stem Cells and Promotes Therapeutic Effect of Docetaxel in Castration-Resistant Prostate Cancer via TPM1 m6A Modification

Prostate cancer (PCa) is a common malignant tumor with high morbidity and mortality worldwide. The prostate cancer stem cell (PCSC) model provides novel insights into the pathogenesis of PCa and its therapeutic response. However, the roles and molecular mechanisms of specific genes in mediating fate decisions of PCSCs and carcinogenesis of PCa remain to be elusive. In this study, we have explored the expression, function, and mechanism of AZGP1P2, a pseudogene of AZGP1, in regulating the stemness and apoptosis of PCSCs and treatment resistance of docetaxel in castration-resistant prostate cancer (CRPC). We revealed that AZGP1P2 was downregulated in CRPC cell lines and PCSCs, while it was positively associated with progression-free interval. Upregulation of the AZGP1P2 enhanced the sensitivity of docetaxel treatment in CRPCs via inhibiting their stemness. RNA pull-down associated with mass spectrometry analysis, co-immunoprecipitation assay, and RNA immunoprecipitation assay demonstrated that AZGP1P2 could bind to UBA1 and RBM15 as a "writer" of methyltransferase to form a compound. UBA1, an E1 ubiquitin-activating enzyme, contributed to RBM15 protein degradation via ubiquitination modification. Methylated RNA immunoprecipitation assay displayed that RBM15 controlled the mRNA decay of TPM1 in m6A methylation. Furthermore, a xenograft mouse model and patient-derived organoids showed that the therapeutic effect of docetaxel in CRPC was increased by AZGP1P2 in vivo. Collectively, these results imply that AZGP1P2 mediates the stemness and apoptosis of PCSCs and promotes docetaxel therapeutic effect by suppressing tumor growth and metastasis via UBA1/RBM15-mediated TPM1 mRNA decay in CRPC.

WTAP gene variants and susceptibility to ovarian endometriosis in a Chinese population

Background: Endometriosis is a common chronic gynecologic disorder with a significant negative impact on women's health. Wilms tumor 1-associated protein (WTAP) is a vital component of the RNA methyltransferase complex for N6-methyladenosine modification and plays a critical role in various human diseases. However, whether single nucleotide polymorphisms (SNPs) of the WTAP gene predispose to endometriosis risk remains to be investigated. Methods: We genotyped three WTAP polymorphisms in 473 ovarian endometriosis patients and 459 control participants using the Agena Bioscience MassArray iPLEX platform. The logistic regression models were utilized to assess the associations between WTAP SNPs and the risk of ovarian endometriosis. Results: In the single-locus analyses, we found that the rs1853259 G variant genotypes significantly increased, while the rs7766006 T variant genotypes significantly decreased the association with ovarian endometriosis risk. Combined analysis indicated that individuals with two unfavorable genotypes showed significantly higher ovarian endometriosis risk (adjusted OR = 1.71 [1.23-2.37], p = 0.001) than those with zero risk genotypes. In the stratified analysis, the risk effect of the rs1853259 AG/GG and rs7766006 GG genotypes was evident in subgroups of age ≤30, gravidity≤1, parity≤1, rASRM stage I, and the rs7766006 GG genotype was associated with worse risk (adjusted OR = 1.64 [1.08-2.48], p = 0.021) in the patients with rASRM stage II + III + IV. The haplotype analysis indicated that individuals with GGG haplotypes had a higher risk of ovarian endometriosis than wild-type AGG haplotype carriers. Moreover, false positive report probability and Bayesian false discovery probability analysis validated the reliability of the significant results. The quantitative expression trait loci analysis revealed that rs1853259 and rs7766006 were correlated with the expression levels of WTAP. Conclusion: Our findings demonstrated that WTAP polymorphisms were associated with susceptibility to ovarian endometriosis among Chinese women.

Crosstalk between m6A modification and alternative splicing during cancer progression

Background N6-methyladenosine (m6A), the most prevalent internal mRNA modification in eukaryotes, is added by m6A methyltransferases, removed by m6A demethylases and recognised by m6A-binding proteins. This modification significantly influences carious facets of RNA metabolism and plays a pivotal role in cellular and physiological processes. Main body Pre-mRNA alternative splicing, a process that generates multiple splice isoforms from multi-exon genes, contributes significantly to the protein diversity in mammals. Moreover, the presence of crosstalk between m6A modification and alternative splicing, with m6A modifications on pre-mRNAs exerting regulatory control, has been established. The m6A modification modulates alternative splicing patterns by recruiting specific RNA-binding proteins (RBPs) that regulate alternative splicing or by directly influencing the interaction between RBPs and their target RNAs. Conversely, alternative splicing can impact the deposition or recognition of m6A modification on mRNAs. The integration of m6A modifications has expanded the scope of therapeutic strategies for cancer treatment, while alternative splicing offers novel insights into the mechanistic role of m6A methylation in cancer initiation and progression. Conclusion This review aims to highlight the biological functions of alternative splicing of m6A modification machinery and its implications in tumourigenesis. Furthermore, we discuss the clinical relevance of understanding m6A-dependent alternative splicing in tumour therapies.

The role of N6-methyladenosine (m6A) in kidney diseases

Chemical modifications are a specific and efficient way to regulate the function of biological macromolecules. Among them, RNA molecules exhibit a variety of modifications that play important regulatory roles in various biological processes. More than 170 modifications have been identified in RNA molecules, among which the most common internal modifications include N6-methyladenine (m6A), n1-methyladenosine (m1A), 5-methylcytosine (m5C), and 7-methylguanine nucleotide (m7G). The most widely affected RNA modification is m6A, whose writers, readers, and erasers all have regulatory effects on RNA localization, splicing, translation, and degradation. These functions, in turn, affect RNA functionality and disease development. RNA modifications, especially m6A, play a unique role in renal cell carcinoma disease. In this manuscript, we will focus on the biological roles of m6A in renal diseases such as acute kidney injury, chronic kidney disease, lupus nephritis, diabetic kidney disease, and renal cancer.

RNA m6A methylation regulators in sepsis

N6-methyladenosine (m6A) modification is a class of epitope modifications that has received significant attention in recent years, particularly in relation to its role in various diseases, including sepsis. Epigenetic research has increasingly focused on m6A modifications, which is influenced by the dynamic regulation of three protein types: ‟Writers" (such as METTL3/METTL14/WTAP)-responsible for m6A modification; ‟Erasers" (FTO and ALKBH5)-involved in m6A de-modification; and ‟Readers" (YTHDC1/2, YTHDF1/2/3)-responsible for m6A recognition. Sepsis, a severe and fatal infectious disease, has garnered attention regarding the crucial effect of m6A modifications on its development. In this review, we attempted to summarize the recent studies on the involvement of m6A and its regulators in sepsis, as well as the significance of m6A modifications and their regulators in the development of novel drugs and clinical treatment. The potential value of m6A modifications and modulators in the diagnosis, treatment, and prognosis of sepsis has also been discussed.

RNA N6‑methyladenosine methyltransferase WTAP promotes the differentiation of endothelial progenitor cells

N6-methyladenosine (m6A) serves a critical role in regulating gene expression and has been associated with various diseases; however, its role in the differentiation of endothelial progenitor cells (EPCs) remains unclear. The present study used liquid chromatography with tandem mass spectrometry and immunofluorescence assays to quantify the levels of m6A in human peripheral blood-derived EPCs (HPB-EPCs) before and after differentiation into mature cells. The present study performed Cell Counting Kit 8, Transwell, and tube formation assays to determine the effects of overexpression and knockdown of Wilms' tumor 1-associated protein (WTAP) on HPB-EPCs. The results revealed that the level of m6A modification was significantly increased during HPB-EPCs differentiation, and WTAP exhibited the most significant alteration among the enzymes involved in m6A regulation. When WTAP was overexpressed in HPB-EPCs, cell proliferation, invasion, and the formation of tubes were improved, whereas WTAP knockdown yielded the opposite effects. In conclusion, the present study highlighted the involvement of m6A in regulating EPC differentiation, with WTAP acting as a promoter of EPC differentiation.

The Regulatory Network of METTL3 in the Nervous System: Diagnostic Biomarkers and Therapeutic Targets

Methyltransferase-like 3 (METTL3) is a typical component of N6-methyladenosine writers that exhibits methyltransferase activity and deposits methyl groups on RNA. Currently, accumulating studies have demonstrated the involvement of METTL3 in the regulation of neuro-physiological and pathological events. However, no reviews have comprehensively summarized and analyzed the roles and mechanisms of METTL3 in these events. Herein, we are focused on reviewing the roles of METTL3 in regulating normal neurophysiological (Neurogenesis, Synaptic Plasticity and Glial Plasticity, Neurodevelopment, Learning and Memory,) and neuropathological (Autism Spectrum Disorder, Major Depressive Disorder, Neurodegenerative disorders, Brain Tumors, Brain Injuries, and Other Brain Disorders) events. Our review found that although the down-regulated levels of METTL3 function through different roles and mechanisms in the nervous system, it primarily inactivates neuro-physiological events and triggers or worsens neuropathological events. In addition, our review suggests that METTL3 could be used as a diagnostic biomarker and therapeutic target in the nervous system. Collectively, our review has provided an up-to-date research outline of METTL3 in the nervous system. In addition, the regulatory network for METTL3 in the nervous system has been mapped, which could provide directions for future research, biomarkers for clinical diagnosis, and targets for disease treatment. Furthermore, this review has provided a comprehensive view, which could improve our understanding of METTL3 functions in the nervous system.

ALKBH5 prevents hepatocellular carcinoma progression by post-transcriptional inhibition of PAQR4 in an m6A dependent manner

BACKGROUND

N6-methyladenosine (m6A) is a prevalent modification of mRNA and is known to play important roles in tumorigenesis in many types of cancer. The function of N6-methyladenosine (m6A) RNA methylation depends on a variety of methyltransferases and demethylases. AlkB homolog 5 (ALKBH5) is a demethylase, and its biological function has not been completely explored in HCC.

RESULTS

ALKBH5 is downregulated and has antitumor effects in HCC cells. In addition, Progestin and AdipoQ Receptor 4 (PAQR4) was identified as a downstream target of ALKBH5 based on transcriptome sequencing and validation studies. We found that ALKBH5 decreases PAQR4 mRNA and protein expression in an N6-methyladenosine (m6A)-dependent manner. The study also showed that ALKBH5 changes PAQR4 expression via the m6A reader IGF2BP1. In both in vivo and in vitro experiments, PAQR4 showed a strong association with the development of HCC. Finally, we found that PAQR4 interacts with AKT and enhances PI3K/AKT pathway activation.

CONCLUSIONS

ALKBH5 inhibits HCC growth by downregulating PAQR4 expression in an m6A-dependent manner, therefore suppressing PI3K/AKT pathway activation.

Novel insights into the interplay between m6A modification and programmed cell death in cancer

N6-methyladenosine (m6A) methylation, the most prevalent and abundant RNA modification in eukaryotes, has recently become a hot research topic. Several studies have indicated that m6A modification is dysregulated during the progression of multiple diseases, especially in cancer development. Programmed cell death (PCD) is an active and orderly method of cell death in the development of organisms, including apoptosis, autophagy, pyroptosis, ferroptosis, and necroptosis. As the study of PCD has become increasingly profound, accumulating evidence has revealed the mutual regulation of m6A modification and PCD, and their interaction can further influence the sensitivity of cancer treatment. In this review, we summarize the recent advances in m6A modification and PCD in terms of their interplay and potential mechanisms, as well as cancer therapeutic resistance. Our study provides promising insights and future directions for the examination and treatment of cancers.

Potential genetic therapies based on m6A methylation for skin regeneration: Wound healing and scars/keloids

Skin wound healing is a complex and multistage process, where any abnormalities at any stage can result in the accumulation of non-functional fibrotic tissue, leading to the formation of skin scars. Epigenetic modifications play a crucial role in regulating gene expression, inhibiting cell fate determination, and responding to environmental stimuli. m6A methylation is the most common post-transcriptional modification of eukaryotic mRNAs and long non-coding RNAs. However, it remains unclear how RNA methylation controls cell fate in different physiological environments. This review aims to discuss the current understanding of the regulatory pathways of RNA methylation in skin wound healing and their therapeutic implications with a focus on the specific mechanisms involved.