N6-methyladenosine (m6A) modification in gynecological malignancies

METTL3-mediated m6A modification of MT1G inhibits papillary thyroid carcinoma cell growth and metastasis via Wnt/β-catenin pathway

BACKGROUND

Downregulation of metallothionein 1 G (MT1G) has been demonstrated in papillary thyroid carcinoma (PTC) tissues. However, the underlying molecular mechanisms of MT1G in PTC progression need to be further explored.

METHODS

MT1G and methyltransferase-like 3 (METTL3) mRNA levels were tested by quantitative real-time PCR. The protein levels of MT1G, METTL3, Wnt3A and β-catenin were measured by western blot. Cell proliferation, apoptosis, invasion and migration were measured by cell counting kit 8 assay, colony formation assay, EdU assay, flow cytometry, transwell assay and wound healing assay. MeRIP analysis was used to detect the MT1G methylation. The interaction between METTL3 and MT1G was evaluated using RIP assay and dual-luciferase reporter assay. A mouse xenograft model was also constructed to explore the roles of METTL3 and MT1G in vivo.

RESULTS

MT1G expression was downregulated in PTC, and its overexpression suppressed PTC cell growth, invasion and migration. METTL3-regulated m6A modification enhanced MT1G mRNA stability. Overexpression of METTL3 repressed PTC cell growth and metastasis, and this effect was reversed by MT1G knockdown. Besides, METTL3/MT1G axis could inhibit the activity of Wnt/β-catenin pathway. Meanwhile, METTL3 enhanced MT1G expression to suppress PTC tumor growth through Wnt/β-catenin pathway in vivo.

CONCLUSION

METTL3-mediated m6A modification of MT1G inhibited PTC cell growth and metastasis via inactivating the Wnt/β-catenin pathway.

The Role of M6A Modification in Autoimmunity: Emerging Mechanisms and Therapeutic Implications

N6-methyladenosine (m6A), a prevalent and essential RNA modification, serves a key function in driving autoimmune disease pathogenesis. By modulating immune cell development, activation, migration, and polarization, as well as inflammatory pathways, m6A is crucial in forming innate defenses and adaptive immunity. This article provides a comprehensive overview of m6A modification features and reveals how its dysregulation affects the intensity and persistence of immune responses, disrupts immune tolerance, exacerbates tissue damage, and promotes the development of autoimmunity. Specific examples include its contributions to systemic autoimmune disorders like lupus and rheumatoid arthritis, as well as conditions that targeting specific organs like multiple sclerosis and type 1 diabetes. Furthermore, this review explores the therapeutic promise of target m6A-related enzymes ("writers," "erasers," and "readers") and summarizes recent advances in intervention strategies. By focusing on the mechanistic and therapeutic implications of m6A modification, this review sheds light on its role as a promising tool for both diagnosis and treatment in autoimmune disorders, laying the foundation for advancements in customized medicine.

Identification of biomarkers and mechanism exploration of ferroptosis related genes regulated by m6A in type 2 diabetes mellitus

PURPOSE

This study is aims to explore the role of ferroptosis genes regulated by N6-methyladenosine (m6A) in Type 2 diabetes mellitus (T2DM).

MATERIAL AND METHODS

Firstly, differentially expressed m6A-FRGs (DEm6A-FRGs) were obtained by intersecting the differentially expressed genes (DEGs) and the m6A-related ferroptosis genes (m6A-FRGs). After enrichment analysis of DEm6A-FRGs, artificial neural network (ANN) and nomogram models were constructed using 4 biomarkers. Moreover, the gene set enrichment analysis of biomarkers was performed. Furthermore, the transcription factors (TF)-mRNA and competing endogenous RNAs (ceRNA) regulatory networks were constructed to reveal the potential regulation of biomarkers at molecular level. In addition, the targeted drugs of biomarkers were predicted, and the molecular docking was used to study the inter-molecular interactions between biomarkers and targeted drugs by "AutoDockvina".

RESULTS

Totals of 10 DEm6A-FRGs were obtained by intersecting the 402 DEGs and 299 m6A-FRGs. Moreover, the ANN model and nomogram model were constructed with 4 biomarkers including CDKN1A, MIOX, MYCN and CD82, among them, CDKN1A was the most important biomarker for forecasting T2DM. Notably, the function of extracellular matrix structural constituent was low expression in CD82 and MIOX, the function of mitochondrial protein-containing complex was high expression in CD82 and CDKN1A. Furthermore, TP63 could regulate CD82, CDKN1A and MIOX, GATA3 could regulate CD82, CDKN1A and MYCN at the same time. The ceRNA network was constructed with 4 mRNAs, 51 miRNAs and 37 lncRNAs, among them, XIST was a key lncRNA that associated with 12 miRNAs, which could influence CDKN1A. In addition, bisphenol A was associated with CD82 and MYCN, CGP 25608 was associated with CDKN1A and MIOX.

CONCLUSION

This study revealed the potential molecular mechanisms of m6A-related ferroptosis genes in T2DM, which could provide novel insights for the clinical diagnosis and treatment of T2DM.

N6-Methyladenosine (m6A)-Circular RNA Pappalysin 1 (circPAPPA) from Cashmere Goats: Identification, Regulatory Network and Expression Potentially Regulated by Methylation in Secondary Hair Follicles Within the First Intron of Its Host Gene

N6-methyladenosine (m6A) is one of the most abundant modifications in eukaryotic RNA molecules and mediates the functional exertion of RNA molecules. We characterized the circPAPPA and validated its potential m6A modification sites in secondary hair follicles (SHFs) of cashmere goats. Furthermore, we generated integrated regulatory networks of the circPAPPA along with enrichment analysis of signaling pathways. We also explored the potential relationship of circPAPPA expression with the first intron methylation of the PAPPA gene in SHFs of cashmere goats. Host source analysis revealed that circPAPPA is derived from the complete exon 2 of the PAPPA gene, spliced in reverse orientation, and predominantly localized in the cytoplasm of SHF stem cells in cashmere goats. The circPAPPA was verified to contain at least four m6A modification sites in SHFs of cashmere goats, including m6A-450/456, m6A-852, m6A-900, and m6A-963. The generated regulatory network indicated complex and diverse regulatory relationships of m6A-circPAPPA with its putative regulatory molecules, including miRNAs, mRNAs, and proteins. Enrichment analysis of signaling pathways showed that m6A-circPAPPA might play multiple functional roles in the growth and development of SHF in cashmere goats through the putative regulatory network mediated by its target miRNAs and regulatory proteins. The first intron methylation of the PAPPA gene most likely is significantly involved in the dynamic expression of m6A-circPAPPA in cashmere goat SHFs. Results from this study provided novel information to elucidate the biological roles and functional regulatory pathways of m6A-circPAPPA in SHF development and the growth of cashmere goat fiber.

ZC3H13 may participate in the ferroptosis process of sepsis-induced cardiomyopathy by regulating the expression of Pnn and Rbm25

BACKGROUND

N6 methyladenosine (m6A) regulates the ferroptosis in different diseases. However, there is no report about the role of the m6A regulator in the ferroptosis process of septic cardiomyopathy (SCM). This study aims to find the potential m6A regulator that participates in the ferroptosis process of SCM.

METHODS

Genes related to m6A were identified through bioinformatics analysis in GSE142615. Then, the expression of Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13 was detected in lipopolysaccharide (LPS)-treated HL-1 cells using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). After overexpression or interference with ZC3H13, Cell Counting Kit-8 measured cell proliferation, flow cytometry detected apoptosis and reactive oxygen species (ROS) accumulation was observed. Then, we identified the potential downstream genes of ZC3H13 through further bioinformatics analysis followed by qRT-PCR and western blotting validation.

RESULTS

There were five differentially expressed genes related to m6A, including Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13. The expression of Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13 mRNA was significantly up-regulated in the LPS-treated HL-1 cells, with ZC3H13 having the highest expression. Furthermore, overexpression of ZC3H13 inhibited the proliferation of HL-1 cells and promoted apoptosis and ROS accumulation. While, interfering with ZC3H13 promoted the proliferation of LPS-treated HL-1 cells, and reduced apoptosis and ROS accumulation. Additionally, si-ZC3H13 promoted the expression of Pnn, GPX4, and SLC7A11; while inhibiting the expression of Rbm25 and Caspase 3.

CONCLUSIONS

In a word, the silence of ZC3H13 increased the proliferation and ferroptosis-related protein expression, decreased apoptosis and ROS accumulation, as well as maybe by regulating Pnn and Rbm25 expression.

Upregulated YTHDC1 mediates trophoblastic dysfunction inducing preterm birth in ART conceptions through enhanced RPL37 translation

Assisted reproductive technology (ART) pregnancies present a higher risk of singleton preterm birth than natural pregnancies, but the underlying molecular mechanism remains largely unknown. RNA m6A modification is a key epigenetic mechanism regulating cellular function, but the role of m6A modification, especially its "reader" YTHDC1, in preterm delivery remains undefined. To delineate the role and epigenetic mechanism of m6A modification in ART preterm delivery, the effects of YTHDC1 on trophoblastic function were evaluated by CCK-8, EdU, Transwell, and flow cytometry analyses post its overexpression or knockdown. Downstream signaling pathways of YTHDC1 were investigated by RNA-seq, and targeted mRNAs were explored by RIP-seq and MeRIP-seq. Upstream transcriptional factors of YTHDC1 were determined by ChIP-seq and luciferase reporter assays. Elevated YTHDC1 was detected in human ART-conceived preterm placentas and in murine preterm placentas post estradiol (E2) exposure. In vitro experiments showed that YTHDC1 promoted trophoblastic cell proliferation and migration, but inhibited cell apoptosis. Mechanistically, E2 was proven to upregulate YTHDC1 expression via retinoid X receptor alpha (RXRA) in trophoblastic cells. Enhanced YTHDC1 expression augmented the translation of RPL37 in an m6A-dependent manner by binding to m6A-modified RPL37 mRNA and concomitantly promoted the overall translational output. Importantly, administration of siRNA targeting YTHDC1 effectively delayed the progression of preterm delivery. In conclusion, the identified E2/RXRA/YTHDC1/RPL37 axis provides new insights into the epigenetic mechanism underlying ART-associated preterm delivery. The findings offer a potential prognostic biomarker and therapeutic target for preterm delivery.

METTL3-mediated m6A modification of CD36: Implications for glucose metabolism and inflammatory dysregulation in follicles of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder that affects women of reproductive age and is characterized by menstrual irregularities, metabolic imbalances and infertility. The pathogenesis of PCOS is complex and not fully understood, and chronic inflammation and insulin resistance are implicated in its progression. In this study, we investigated the role of m6A methylation, an important epigenetic modification, in the pathogenesis of PCOS. Using methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq), we mapped the m6A methylation profile in granulosa cells from patients with PCOS and identified a significant regulatory effect on gene expression. CD36 is a novel m6A-regulated gene that may facilitate the progression of PCOS. We demonstrated that METTL3, an m6A methyltransferase, modulated CD36 expression and influenced glucose metabolism and inflammatory responses in PCOS. Employing KGN cells as a model of insulin resistance, we observed that CD36 knockdown ameliorated the impaired glucose uptake and significantly reduced the production of pro-inflammatory cytokines. These findings are consistent with the results of CD36 inhibition in a mouse model of PCOS, indicating a role of CD36 in modulating the disease phenotype. Our study delineates a previously unrecognized epigenetic mechanism involving m6A methylation in PCOS, highlighting the potential of targeting the METTL3-CD36 axis as a therapeutic strategy for managing ovarian inflammation and metabolic dysregulation in patients with PCOS.

Epigenetic control of dental stem cells: progress and prospects in multidirectional differentiation

Dental stem cells, with their exceptional proliferative capacity and multidirectional differentiation potential, hold significant promise for dental and oral tissue regeneration. Epigenetic inheritance, which involves stable and heritable changes in gene expression and function without alterations to the DNA sequence, plays a critical role in numerous biological processes. Environmental factors are particularly influential in epigenetic inheritance, as variations in exposure can lead to changes in epigenetic modifications that subsequently impact gene expression. Epigenetic mechanisms are widely involved in processes such as bone homeostasis, embryogenesis, stem cell fate determination, and disease development. Recently, the epigenetic regulation of dental stem cells has attracted considerable research attention. This paper reviews studies focused on the epigenetic mechanisms governing the multidirectional differentiation of dental stem cells.

METTL3 accelerates staphylococcal protein A (SpA)-induced osteomyelitis progression by regulating m6A methylation-modified miR-320a

Osteomyelitis (OM) is an inflammatory disease of bone infection and destruction characterized by dysregulation of bone homeostasis. Staphylococcus aureus (SA) has been reported to be the most common pathogen causing infectious OM. Recent studies have demonstrated that N6-methyladenosine (m6A) regulators are associated with the development of OM. However, the molecular mechanism of m6A modifications in OM remains unclear. Here, we investigated the function of methyltransferase-like 3 (METTL3)-mediated m6A modification in OM development. In this study, human bone mesenchymal stem cells (hBMSCs) were treated with staphylococcal protein A (SpA), a vital virulence factor of SA, to construct cell models of OM. Firstly, we found that METTL3 was upregulated in OM patients and SpA-induced hBMSCs, and SpA treatment suppressed osteogenic differentiation and induced oxidative stress and inflammatory injury in hBMSCs. Functional experiments showed that METTL3 knockdown alleviated the inhibition of osteogenic differentiation and the promotion of oxidative stress and inflammation in SpA-treated hBMSCs. Furthermore, METTL3-mediated m6A modification upregulated miR-320a expression by promoting pri-miR-320a maturation, and the mitigating effects of METTL3 knockdown on SpA-mediated osteogenic differentiation, oxidative stress and inflammatory responses can be reversed by miR-320 mimic. In addition, we demonstrated that phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) was a downstream target of miR-320a, upregulation of PIK3CA alleviated miR-320a-induced inhibition of osteogenic differentiation, and upregulation of oxidative stress and inflammatory responses during SpA infection. Finally, we found that silencing METTL3 alleviated OM development by regulating the miR-320a/PIK3CA axis. Taken together, our data demonstrated that the METTL3/m6A/miR-320a/PIK3CA axis regulated SpA-mediated osteogenic differentiation, oxidative stress, and inflammatory responses in OM, which may provide a new therapeutic strategy for OM patients.

Ultrasensitive Biosensors Detecting m6A in Blood: Achieving Early Screening and Typing of Tumors

N6-methyladenosine (m6A) modification is one of the most widespread RNA modifications in eukaryotes and is involved in cancer development and progression by regulating oncogene expression. Herein, a reticulated rolling circle amplification (RCA) cascade reaction was used to construct a novel electrochemical biosensor for ultrasensitive detection of m6A, employing ferrocene-tyramine (Fc-Tyr) molecules as electroactive probes. In this strategy, the RCA cascade reaction not only amplifies specific circular DNA in the designed template to reduce the binding with similar nucleic acid sequences but also generates a long ssDNA through multiple repetitions to capture a large number of electrochemical signal probes and achieve the amplification of electrochemical biosensing signals. The developed biosensor demonstrated high selectivity and sensitivity toward m6A in the range of 0.5 pM-150 nM, with a detection limit of 14.07 fM. Meanwhile, total RNA extracted from cell samples was analyzed for m6A expression levels using the developed biosensor and a commercial colorimetric immunoassay, the biosensor and immunoassay showed consistent results. In addition, m6A levels in clinical serum samples were assessed using the developed electrochemical biosensor, which showed that m6A expression was much lower in healthy individuals than in cancer patients, therefore the biosensor is promising for cancer typing. This study provides a new method for rapid and convenient tumor marker detection in clinical practice, as well as a new idea for sensitive detection of other biomolecules.

RNA modification regulators as promising biomarkers in gynecological cancers

This review explores the evolving landscape of gynecological oncology by focusing on emerging RNA modification signatures as promising biomarkers for assessing the risk and progression of ovarian, cervical, and uterine cancers. It provides a comprehensive overview of common RNA modifications, especially m6A, and their roles in cellular processes, emphasizing their implications in gynecological cancer development. The review meticulously examines specific m6A regulators including "writers", "readers", and "erasers" associated with three gynecological cancer types, discussing their involvement in initiation and progression. Methodologies for detecting RNA modifications are surveyed, highlighting advancements in high-throughput techniques with high sensitivity. A critical analysis of studies identifying m6A regulators as potential biomarkers is presented, addressing their diagnostic or prognostic significance. Mechanistic insights into RNA modification-mediated cancer progression are explored, shedding light on molecular pathways and potential therapeutic targets. Despite current challenges, the review discusses ongoing research efforts, future directions, and the transformative possibility of RNA modifications on early assessment and personalized therapy in gynecological oncology.

The regulatory mechanisms of N6-methyladenosine modification in ferroptosis and its implications in disease pathogenesis

HEADING AIMS

Based on the current knowledge of the molecular mechanisms by which m6A influences ferroptosis, our objective is to underscore the intricate and interdependent relationships between m6A and the principal regulatory pathways of ferroptosis, as well as other molecules, emphasizing its relevance to diseases associated with this cell death mode.

MATERIALS AND METHODS

We conducted a literature search using the keywords "m6A and ferroptosis" across PubMed, Web of Science, and Medline. The search was limited to English-language publications from 2017 to 2024. Retrieved articles were managed using Endnote software. Two authors independently screened the search results and reviewed the full texts of selected articles.

KEY FINDINGS

Abnormal m6A levels are often identified as critical regulators of ferroptosis. Specifically, "writers", "readers" and "erasers" that dynamically modulate m6A function regulate various pathways in ferroptosis including iron metabolism, lipid metabolism and antioxidant system. Additionally, we provide an overview of the role of m6A-mediated ferroptosis in multiple diseases and summarize the potential applications of m6A-mediated ferroptosis, including its use as a therapeutic target for diseases and as diagnostic as well as prognostic biomarkers.

SIGNIFICANCE

N6-methyladenosine (m6A) modification, a prevalent RNA modification in eukaryotic cells, is crucial in regulating various aspects of RNA metabolism. Notably, accumulating evidence has implicated m6A modification in ferroptosis, a form of iron-dependent cell death characterized by elevated iron levels and lipid peroxide accumulation. Overall, this review sheds light on the potential diagnostic and therapeutic applications of m6A regulators in addressing conditions associated with ferroptosis.

Epitranscriptomics and cervical cancer: the emerging role of m6A, m5C and m1A RNA modifications

Cervical cancer (CC), one of the most prevalent and detrimental gynaecologic cancers, evolves through genetic and epigenetic alterations resulting in the promotion of oncogenic activity and dysfunction of tumour-suppressing mechanisms. Despite medical advancement, the prognosis for advanced-stage patients remains extremely low due to high recurrence rates and resistance to existing treatments. Thereby, the search for potential prognostic biomarkers is heightened to unravel new modalities of CC pathogenesis and to develop novel anti-cancer therapies. Epitranscriptomic modifications, reversible epigenetic RNA modifications, regulate various biological processes by deciding RNA fate to mediating RNA interactions. This narrative review provides insight into the cellular and molecular roles of endogenous RNA-editing proteins and their associated epitranscriptomic modifications, especially N6-methyladenosine (m6A), 5-methylcytosine (m5C) and N1-methyladenosine (m1A), in governing the development, progression and metastasis of CC. We discussed the in-depth epitranscriptomic mechanisms underlying the regulation of over 50 RNAs responsible for tumorigenesis, proliferation, migration, invasion, survival, autophagy, stemness, epithelial-mesenchymal transition, metabolism (glucose, lipid, glutamate and glutamine), resistance (drug and radiation), angiogenesis and recurrence of CC. Additionally, we provided a concise overview of the therapeutic potential of targeting the altered expression of endogenous RNA-editing proteins and aberrant deposition of RNA modifications on both coding and non-coding RNAs in CC.

STM2457 Inhibits METTL3-Mediated m6A Modification of miR-30c to Alleviate Spinal Cord Injury by Inducing the ATG5-Mediated Autophagy

OBJECTIVE

The study aimed to investigate the role of N6-methyladenosine (m6A) modification in spinal cord injury (SCI) and its underlying mechanism, focusing on the interplay between m6A methyltransferase-like 3 (METTL3), miR-30c, and autophagy-related proteins.

METHODS

An SCI model was established in rats, and changes in autophagy-related proteins, m6A methylation levels, and miR-30c levels were analyzed. Hydrogen peroxide (H2O2)-stimulated spinal cord neuron cells (SCNCs) were used to assess the impact of METTL3 overexpression. The effects of STM2457, an antagonist of METTL3, were evaluated on cell viability, apoptosis, and autophagy markers in H2O2-stimulated SCNCs.

RESULTS

In the SCI model, decreased levels of autophagy markers and increased m6A methylation, miR-30c levels, and METTL3 were observed. Overexpression of METTL3 in SCNCs led to reduced cell viability, increased apoptosis, and suppressed autophagy. Conversely, co-overexpression of autophagy-related protein 5 (ATG5) or miR-30c inhibition reversed these effects. Knocking out METTL3 yielded opposite results. STM2457 treatment improved cell viability, reduced apoptosis, and upregulated autophagy markers in SCNCs, which also enhanced functional recovery in rats as measured by the Basso-Beattie-Bresnahan score and inclined plate test.

CONCLUSION

STM2457 alleviated SCI by suppressing METTL3-mediated m6A modification of miR-30c, which in turn induces ATG5-mediated autophagy. This study provides insights into the role of m6A modification in SCI and suggests a potential therapeutic approach through targeting METTL3.

Treatment of Intracerebral Hemorrhage with Traditional Chinese Medicine Monomer Wogonin by Modifying NLRP3 with METTL14 to Inhibit Neuronal Cell Pyroptosis

The aim of this study was to investigate the alleviating effect of wogonin on intracerebral hemorrhage (ICH) and its mechanism. The hemin-treated PC-12 cells were constructed to mimic ICH in vitro. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis was used for cell viability measurement and flow cytometry was for pyroptosis detection. Enzyme-linked immunosorbent assay (ELISA) assay and western blot were used to detect the protein levels of pyroptosis-related proteins. The modification level of N6-methyladenosine (m6A) methylation was detected by quantitative real-time polymerase chain reaction (qRT-PCR) combined with m6A dot blot assays. Molecular docking experiments analyzed the binding of wogonin and METTL14 protein. The correlation between METTL14 and NLRP3 was confirmed by bioinformatics analysis and dual luciferase reporter gene detection. ICH was induced in mice injected with collagenase into the basal ganglia, and the neurobehavioral damage was evaluated. Triphenyltetrazolium chloride monohydrate (TTC) staining and neurological scores were used to assess brain damage in mice. The results demonstrated that wogonin alleviated neuronal cell pyroptosis, and was molecularly docked with METTL14. Overexpression of METTL14 partly reversed the protecting effects of wogonin on brain in vitro and in vivo. Furthermore, NLRP3 was methylated by METTL14. Taken together, wogonin inhibits neuronal pyroptosis and thus treats IHC by inhibiting METTL14 and its methylated NLRP3.

N6-methyladenosine-modified ALDH9A1 modulates lipid accumulation and tumor progression in clear cell renal cell carcinoma through the NPM1/IQGAP2/AKT signaling pathway

Aldehyde dehydrogenases superfamily (ALDHs), which are ubiquitously present in various organisms with diverse subcellular localizations, play a crucial role in regulating malignant tumor progression; Nevertheless, their involvement in clear cell renal cell carcinoma (ccRCC) has not been elucidated. In this study, we performed comprehensive bioinformatics analyses on the 19 ALDHs genes, and identified ALDH9A1 as a key contributor in ccRCC. Expression patterns and clinical relevance of ALDH9A1 were determined using bioinformatics analyses, real-time PCR, western blotting, and immunohistochemistry. To explore the underlying mechanism behind the tumor suppressor role of ALDH9A1, RNA sequencing, methylated RNA immunoprecipitation, luciferase reporter assay, mass spectroscopy, immunoprecipitation, mutational studies and immunofluorescence were employed. The impact of ALDH9A1 in ccRCC progression and metabolic programming was assessed through both in vitro and in vivo. Here, this study revealed ALDH9A1 as a tumor suppressor gene in ccRCC. The fat mass and obesity associated protein (FTO) was identified as a demethylase for ALDH9A1 mRNA, resulting in its reduced stability and expression levels in ccRCC. Functional experiments demonstrated that the deficiency of ALDH9A1 in ccRCC promoted tumor proliferation, invasion, migration and lipid accumulation. Mechanistic insights illustrated that the diminished levels of ALDH9A1 resulted in the failure to sequester nucleophosmin 1 (NPM1) within cytoplasm, thereby suppressing the transcription of IQ motif containing the GTPase-activating protein 2 (IQGAP2), subsequently activating the AKT-mTOR signaling, ultimately fostering tumor progression and lipid accumulation. In conclusion, the present study highlights the robust prognostic significance of ALDH9A1 and delivers a comprehensive understanding of ALDH9A1-NPM1-IQGAP2-AKT axis in ccRCC. These findings established a solid research foundation for novel therapeutic strategies for ccRCC patients.

ALKBH5-mediated m6A modification of circFOXP1 promotes gastric cancer progression by regulating SOX4 expression and sponging miR-338-3p

Circular RNAs (circRNAs) have recently been suggested as potential functional modulators of cellular physiology processes in gastric cancer (GC). In this study, we demonstrated that circFOXP1 was more highly expressed in GC tissues. High circFOXP1 expression was positively associated with tumor size, lymph node metastasis, TNM stage, and poor prognosis in patients with GC. Cox multivariate analysis revealed that higher circFOXP1 expression was an independent risk factor for disease-free survival (DFS) and overall survival (OS) in GC patients. Functional studies showed that increased circFOXP1 expression promoted cell proliferation, cell invasion, and cell cycle progression in GC in vitro. In vivo, the knockdown of circFOXP1 inhibited tumor growth. Mechanistically, we observed ALKBH5-mediated m6A modification of circFOXP1 and circFOXP1 promoted GC progression by regulating SOX4 expression and sponging miR-338-3p in GC cells. Thus, our findings highlight that circFOXP1 could serve as a novel diagnostic and prognostic biomarker and potential therapeutic target for GC.

Palmatine inhibits expression fat mass and obesity associated protein (FTO) and exhibits a curative effect in dextran sulfate sodium (DSS)-induced experimental colitis

BACKGROUND

Ulcerative colitis (UC) is an inflammatory disease whose pathogenesis and mechanisms have not been fully described. The m6A methylation modification is a general mRNA modification in mammalian cells and is closely associated with the onset and progression of inflammatory bowel disease (IBD). Palmatine (PAL) is a biologically active alkaloid with anti-inflammatory and protective effects in animal models of colitis. Accordingly, we examined the role of PAL on colitis by regulating N6-methyladenosine (m6A) methylation.

METHODS

A rat experimental colitis model was established by 5 % dextran sulfate sodium (DSS) in drinking water for seven days, then PAL treatment was administered for seven days. The colonic tissue pathology was assessed using hematoxylin-eosin (HE) and disease activity index (DAI). In in vitro studies, a human, spontaneously immortalized non-cancerous colon mucosal epithelial cell line (NCM460) was exposed to 2 % DSS and treated with PAL and cell viability was assayed using Cell Counting Kit-8 (CCK-8). The levels of tumor necrosis factor α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 were detected by enzyme-linked immunosorbent assay (ELISA) kits. The level of Zonula occludens-1 (ZO-1) was dectected by immunofluorescence. Transepithelial electrical resistance (TEER) of cells was also assessed. The methyltransferase-like 3 (METTL3), METTL14, AlkB homologate 5 (ALKBH5), and fat mass and obesity-associated protein (FTO) expression levels were assessed by western blotting. The localized expression of m6A was measured by immunofluorescence.

RESULTS

PAL significantly prevented bodyweight loss and shortening of the colon in experimental colitis rats, as well as decreasing the DAI and histological damage scores. Furthermore, PAL inhibited the levels of inflammatory factors (TNF-α, IL-6, IL-8, and IL-1β) in both DSS treated rats and NCM460 cells. In addition, PAL enhanced the expression level of ZO-1, and increased the transepithelial electrical resistance to repaire intestinal barrier dysfunction. Colitis occurred due to decreased m6A levels, and the increased FTO expression led to a colitis phenotype. PAL markedly enhanced the METTL3 and METTL14 expression levels while decreasing ALKBH5 and FTO expression levels.

CONCLUSIONS

The findings demonstrated that PAL improved DSS-induced experimental colitis. This effect was associated with inhibiting FTO expression and regulating m6A methylation.

YTHDF2 alleviates microglia activation via promoting circHIPK2 degradation

Microglial activation is a common cellular dysfunction in central nervous system inflammation, accompanied by abnormal expression of circular RNAs (circRNAs). YTHDF2, a N6-methyladenosine (m6A) reader, is known as a key element in RNA degradation. Here, lipolysaccharide induced microglia activation in mouse cortex and BV2 cells, accompanied by the decreased YTHDF2 and elevated circHIPK2. YTHDF2 overexpression or circHIPK2 knockdown in BV2 microglia inhibited the expressions of iNOS protein, IL-1β mRNA and IL-6 mRNA. Subsequent experiments revealed that YTHDF2 facilitated circHIPK2 degradation, thereby alleviating microglia activation. These findings suggest that YTHDF2 overexpression could serve as a therapeutic approach for inhibiting microglia activation.

Regulation of ULK1 by WTAP/IGF2BP3 axis enhances mitophagy and progression in epithelial ovarian cancer

There is a pressing need for innovative therapeutic strategies for patients with epithelial ovarian cancer (EOC). Previous studies have shown that UNC-51-like kinase 1 (ULK1), a serine/threonine kinase, is crucial in regulating cellular autophagy and mitophagy across various tumor types. However, the clinical implications, biological functions, and potential mechanisms of ULK1 in EOC remain poorly understood. This study demonstrates that ULK1 expression is upregulated in EOC tissue samples and EOC cell lines, with increased ULK1 expression correlating with poor prognosis. Functionally, overexpressed ULK1 enhances the proliferation and migration abilities of EOC cells both in vitro and in vivo. Mechanistically, ULK1 was identified as an m6A target of WTAP. WTAP-mediated m6A modification of ULK1 enhanced its mRNA stability in an IGF2BP3-dependent manner, leading to elevated ULK1 expression and enhanced mitophagy in EOC. In summary, our research reveals that the WTAP/IGF2BP3-ULK1 axis significantly influences protective mitophagy in EOC, contributing to its progression. Therefore, the regulatory mechanisms and biological function of ULK1 identify it as a potential molecular target for therapeutic intervention in EOC.

Characterization of m6A methylation modifications in gastric cancer

Widely recognized as an essential epitranscriptomic modification, RNA N6-methyladenosine (m6A) is involved in both physiological and pathological processes. Here, we want to investigate m6A modification's potential roles in gastric cancer. Gastric cancer samples were selected from TCGA-STAD and GEO (GSE84426, GSE84433) datasets. Based on 18 regulators of m6A, m6A modification patterns were thoroughly evaluated in gastric cancer samples. Principal component analysis algorithms were used to construct the m6Ascore, using which, m6A modification features in tumor somatic mutations and immune checkpoint blockade therapy were analyzed. 34 gastric cancer samples were collected to verify the effectiveness of the m6Ascore. Here, we determined three different m6A modification patterns. m6Acluster-C modification pattern presented immune activation-associated enrichment pathways and have significant survival advantages. Then, in gastric cancer, m6Ascore could act as an independent prognostic biomarker. A significant survival benefit was exhibited in patients with high m6Ascore. Moreover, the modification signature of m6A uncovered in this study would help to predict immune checkpoint blockade therapy's responses. In conclusion, our discoveries all pointed to the fact that modification patterns of m6A were linked to the TME. Moreover, evaluation of individual tumor's m6A modification pattern will help to guide immunotherapy strategies that shows more therapeutic effects.

Emerging role of m6A modification in fibrotic diseases and its potential therapeutic effect

Fibrosis can occur in a variety of organs such as the heart, lung, liver and kidney, and its pathological changes are mainly manifested by an increase in fibrous connective tissue and a decrease in parenchymal cells in organ tissues, and continuous progression can lead to structural damage and organ hypofunction, or even failure, seriously threatening human health and life. N6-methyladenosine (m6A) modification, as one of the most common types of internal modifications of RNA in eukaryotes, exerts a multifunctional role in physiological and pathological processes by regulating the metabolism of RNA. With the in-depth understanding and research of fibrosis, we found that m6A modification plays an important role in fibrosis, and m6A regulators can further participate in the pathophysiological process of fibrosis by regulating the function of specific cells. In our review, we summarized the latest research advances in m6A modification in fibrosis, as well as the specific functions of different m6A regulators. In addition, we focused on the mechanisms and roles of m6A modification in cardiac fibrosis, liver fibrosis, pulmonary fibrosis, renal fibrosis, retinal fibrosis and oral submucosal fibrosis, with the aim of providing new insights and references for finding potential therapeutic targets for fibrosis. Finally, we discussed the prospects and challenges of targeted m6A modification in the treatment of fibrotic diseases.

RNA m6A modification in prostate cancer: A new weapon for its diagnosis and therapy

Prostate cancer (PCa) is the most common malignant tumor and the second leading cause of cancer-related mortality in men worldwide. Despite significant advances in PCa therapy, the underlying molecular mechanisms have yet to be fully elucidated. Recently, epigenetic modification has emerged as a key player in tumor progression, and RNA-based N6-methyladenosine (m6A) epigenetic modification was found to be crucial. This review summarizes comprehensive state-of-art mechanisms underlying m6A modification, its implication in the pathogenesis, and advancement of PCa in protein-coding and non-coding RNA contexts, its relevance to PCa immunotherapy, and the ongoing clinical trials for PCa treatment. This review presents potential m6A-based targets and paves a new avenue for diagnosing and treating PCa, providing new guidelines for future related research through a systematic review of previous results.

The role of RNA methyltransferase METTL3 in gynecologic cancers: Results and mechanisms

N6-methyladenosine (m6A) methylation is the most prevalent mRNA modification in eukaryotes, and it is defined as the methylation of nitrogen atoms on the six adenine (A) bases of RNA in the presence of methyltransferases. Methyltransferase-like 3 (Mettl3), one of the components of m6A methyltransferase, plays a decisive catalytic role in m6A methylation. Recent studies have confirmed that m6A is associated with a wide spectrum of biological processes and it significantly affects disease progression and prognosis of patients with gynecologic tumors, in which the role of Mettl3 cannot be ignored. Mettl3 is involved in numerous pathophysiological functions, such as embryonic development, fat accumulation, and tumor progression. Moreover, Mettl3 may serve as a potential target for treating gynecologic malignancies, thus, it may benefit the patients and prolong survival. However, there is a need to further study the role and mechanism of Mettl3 in gynecologic malignancies. This paper reviews the recent progression on Mettl3 in gynecologic malignancies, hoping to provide a reference for further research.

Role of m6A modification in dysregulation of Wnt/β-catenin pathway in cancer

N6-methyladenosine (m⁶A) modification is the most abundant post-transcriptional regulation of RNAs in eukaryotes. Dysregulation of m⁶A readers, writers, and erasers can significantly promote tumorigenesis by altering the expression of various genes. Wnt/β-catenin is an evolutionarily conserved signaling pathway that has recently been linked to the pathogenesis of many cancers. Given the significance of this pathway in regulating normal tissue homeostasis and stem cell differentiation, a subtle understanding of the molecular mechanism underlying its dysregulation is required for effective targeting. There is mounting evidence that m⁶A regulators are highly implicated in the dysregulation of the Wnt/β-catenin signaling pathway. Since m⁶A regulators can affect Wnt pathway components and dysregulation of either leads to carcinogenesis, this study aims to clarify the relationship between m⁶A regulators and the Wnt/β-catenin signaling pathway to investigate their combined impact on tumorigenesis.

An overview of the effects and mechanisms of m6 A methylation on innate immune cells in sepsis

Introduction

Sepsis is a severe clinical syndrome caused by dysregulated systemic inflammatory responses to infection. Methylation modification, as a crucial mechanism of RNA functional modification, can manipulate the immunophenotype and functional activity of immune cells to participate in sepsis progression. This study aims to explore the mechanism of N6-methyladenosine (m6A) methylation modification in immune cell-mediated sepsis through keyword search.

Methods

Literature retrieval.

Results and Discussion

Literature retrieval reveals that m6A methylation is implicated in sepsis-induced lung injury and myocardial injury,as well as sepsis-related encephalopathy. Furthermore, it is found that m6A methylation can regulate sepsis by inhibiting the chemotaxis of neutrophils and the formation of neutrophil extracellular traps and suppressing macrophage phagocytosis, thereby playing a role in sepsis.

RNA m6A modification in liver biology and its implication in hepatic diseases and carcinogenesis

N6-methyladenosine (m6A) is the most prevalent internal modification in eukaryotic RNAs. This modification is regulated by three different factors (writers, erasers, and readers) and affects multiple aspects of RNA metabolism, including RNA splicing, nuclear export, translation, stability and decay. The m6A-mediated modification plays important roles in posttranscriptional regulation of gene expression and mediates a variety of cellular and biological processes. Accordingly, deregulation in m6A modification is closely related to the occurrence and development of human diseases. The liver is the largest digestive and metabolic organ in human and recent studies have shown that m6A modification is importantly implicated in liver cellular and physiological functions and in the pathogenesis of hepatic diseases and cancers. In the current review, we summarize the functions of m6A in RNA metabolism and its roles in liver cell biology and discuss its implication in hepatic diseases and carcinogenesis.

Crosstalk among N6-methyladenosine modification and RNAs in central nervous system injuries

Central nervous system (CNS) injuries, including traumatic brain injury (TBI), intracerebral hemorrhage (ICH) and ischemic stroke, are the most common cause of death and disability around the world. As the most common modification on ribonucleic acids (RNAs), N6-methyladenosine (m6A) modification has recently attracted great attentions due to its functions in determining the fate of RNAs through changes in splicing, translation, degradation and stability. A large number of studies have suggested that m6A modification played an important role in brain development and involved in many neurological disorders, particularly in CNS injuries. It has been proposed that m6A modification could improve neurological impairment, inhibit apoptosis, suppress inflammation, reduce pyroptosis and attenuate ferroptosis in CNS injuries via different molecules including phosphatase and tensin homolog (PTEN), NLR family pyrin domain containing 3 (NLRP3), B-cell lymphoma 2 (Bcl-2), glutathione peroxidase 4 (GPX4), and long non-coding RNA (lncRNA). Therefore, m6A modification showed great promise as potential targets in CNS injuries. In this article, we present a review highlighting the role of m6A modification in CNS injuries. Hence, on the basis of these properties and effects, m6A modification may be developed as therapeutic agents for CNS injury patients.