METTL14 suppresses proliferation and metastasis of colorectal cancer by down-regulating oncogenic long non-coding RNA XIST

Interplay of m6A RNA methylation and gut microbiota in modulating gut injury

The gut microbiota undergoes continuous variations among individuals and across their lifespan, shaped by diverse factors encompassing diet, age, lifestyle choices, medication intake, and disease states. These microbial inhabitants play a pivotal role in orchestrating physiological metabolic pathways through the production of metabolites like bile acids, choline, short-chain fatty acids, and neurotransmitters, thereby establishing a dynamic "gut-organ axis" with the host. The intricate interplay between the gut microbiota and the host is indispensable for gut health, and RNA N6-methyladenosine modification, a pivotal epigenetic mark on RNA, emerges as a key player in this process. M6A modification, the most prevalent internal modification of eukaryotic RNA, has garnered significant attention in the realm of RNA epigenetics. Recent findings underscore its potential to influence gut microbiota diversity and intestinal barrier function by modulating host gene expression patterns. Conversely, the gut microbiota, through its impact on the epigenetic landscape of host cells, may indirectly regulate the recruitment and activity of RNA m6A-modifying enzymes. This review endeavors to delve into the biological functions of m6A modification and its consequences on intestinal injury and disease pathogenesis, elucidating the partial possible mechanisms by which the gut microbiota and its metabolites maintain host intestinal health and homeostasis. Furthermore, it also explores the intricate crosstalk between them in intestinal injury, offering a novel perspective that deepens our understanding of the mechanisms underlying intestinal diseases.

Progress of IL-10 and liver metastasis

Liver metastasis can occur in a wide range of cancers and have a significant impact on patient survival and prognosis. Once liver metastasis occurs, patients often lose the opportunity for surgery, and although a small percentage of patients can undergo hepatic resection to prolong survival, the benefit is not great. There were also many factors affecting liver metastasis, including reprogramming of the primary tumor metabolism, disturbances in the immune microenvironment and immune cells, alterations in the gut microbiota, and epigenetic changes. Interleukin-10 (IL-10) has a dual role as a cytokine that has been found in recent years to be pro-inflammatory as well as pro-liver metastasis. IL-10 exerts pro-metastatic effects mainly by regulating the polarization of tumor macrophages in the tumor microenvironment, especially by promoting the polarization of M2 macrophages. However, the role of IL-10 in tumorigenesis and progression remains controversial and the molecular mechanism involved in promoting liver metastasis is currently unclear. In view of the increasing role of IL-10 in promoting liver metastasis, this review summarizes the role of IL-10 in liver metastasis of colorectal cancer, breast cancer and other tumors in recent years, and provides ideas for subsequent clinical practice and basic research.

Interactions between long non-coding RNAs and m6 A modification in cancer

Long non-coding RNAs (lncRNAs) are a class of transcripts exceeding 200 nucleotides (nt) in length, which are broadly implicated in a broad spectrum of physiological and pathological processes, including allelic imprinting, genome packaging, chromatin remodeling, transcriptional activation and disruption, as well as the occurrence and progression of oncogenesis. N6-methyladenosine (m6 A) methylation stands as the most prevalent RNA modification, affecting multiple facets of RNA biology such as stability, splicing, transport, translation, degradation, and tertiary structure. Aberrant m6 A modifications are intimately implicated in cancer progression. In recent years, there has been a growing number of studies illuminating the dynamic interplay between lncRNAs and m6 A modifications, revealing that lncRNAs can modulate the activity of m6 A regulators, while m6 A not only affects the structural integrity but also the translational efficiency and stability of lncRNAs. Together, the interactions between lncRNAs and m6 A modifications significantly impact downstream oncogenes, cancer suppressor genes, cellular metabolism, epithelial-mesenchymal transition, angiogenesis, drug transport, DNA homology repair, and epigenetics, subsequently influencing tumorigenesis, metastasis, and drug resistance. This article endeavors to clarify the functions and mechanisms of lncRNAs and m6 A modifications interaction in cancer to provide promising insights for cancer diagnosis and therapeutic strategies.

METTL3 orchestrates cancer progression by m6A-dependent modulation of oncogenic lncRNAs

RNA modifications, particularly N6-methyladenosine (m6A), play crucial roles in gene expression regulation. While extensively studied in the context of mRNA, the impact of m6A on long non-coding RNAs (lncRNAs) remains elusive. This research aimed to reveal the regulatory landscape of m6A in lncRNA expression. In a comprehensive analysis across 6219 samples spanning 12 cancer types, we unveiled METTL3 as the most potent regulator of lncRNA expression among the examined 19 m6A regulators. A total of 397 METTL3-mediated m6A-modified lncRNAs (mmlncRs) were unveiled across 12 cancer types, indicating a consistent mechanism of METTL3-mediated lncRNA regulation. Functional assays demonstrated that METTL3 knockout significantly impeded lung cancer cell proliferation and progression. Leveraging RNA-seq and MeRIP-seq, we identified C1RL-AS1 as a bona fide m6A target of METTL3 in lung cancer, revealing its oncogenic role. Mechanistically, METTL3 depletion disrupts m6A modification on C1RL-AS1, leading to its downregulated expression. YTHDF2 binds to C1RL-AS1, maintaining its stability in a m6A-dependent manner. This study provides a valuable resource for the exploration of mmlncRs as promising therapeutic targets in cancers, shedding light on the intricate regulatory networks orchestrated by METTL3.

Summary of the mechanism of ferroptosis regulated by m6A modification in cancer progression

The most common form of internal RNA modification in eukaryotes is called n6-methyladenosine (m6A) methylation. It has become more and more well-known as a research issue in recent years since it alters RNA metabolism and is involved in numerous biological processes. Currently, m6A alteration offers new opportunities in clinical applications and is intimately linked to carcinogenesis. Ferroptosis-a form of iron-dependent, lipid peroxidation-induced regulated cell death-was discovered. In the development of cancer, it has become an important factor. According to newly available data, ferroptosis regulates tumor growth, and cancer exhibits aberrant m6A levels in crucial ferroptosis regulatory components. On the other hand, m6A has multiple roles in the development of tumors, and the relationship between m6A-modified ferroptosis and malignancies is quite intricate. In this review, we first give a thorough review of the regulatory and functional roles of m6A methylation, focusing on the molecular processes of m6A through the regulation of ferroptosis in human cancer progression and metastasis, which are strongly associated to cancer initiation, progression, and drug resistance. Therefore, it is crucial to clarify the relationship between m6A-mediated regulation of ferroptosis in cancer progression, providing a new strategy for cancer treatment with substantial clinical implications.

A review of molecular interplay between inflammation and cancer: The role of lncRNAs in pathogenesis and therapeutic potential

The inflammatory microenvironment (IME) has been demonstrated to facilitate the initiation and progression of tumors throughout the inflammatory process. Simultaneously, cancer can initiate or intensify the inflammatory response, thereby promoting tumor progression. This review examines the dual role of long non-coding RNAs (lncRNAs) in the interplay between inflammation and cancer. LncRNA modulate inflammation-induced cancer by influencing the activation of signaling pathways (NF-κB, Wnt/β-catenin, mTOR, etc), microRNA (miRNA) sponging, protein interactions, interactions with immune cells, and encoding short peptides. In contrast, lncRNAs also impact cancer-induced inflammatory processes by regulating cytokine expression, mediating tumor-derived extracellular vesicles (EVs), modulating intracellular reactive oxygen species (ROS) levels, and facilitating metabolic reprogramming. Furthermore, the therapeutic potential of lncRNA and the challenges of clinical translation were explicitly discussed as well. Overall, this review aims to provide a comprehensive and systematic resource for future researchers investigating the impact of lncRNAs on inflammation and cancer.

HDAC2-Mediated METTL3 Delactylation Promotes DNA Damage Repair and Chemotherapy Resistance in Triple-Negative Breast Cancer

The current treatment of triple-negative breast cancer (TNBC) is still primarily based on platinum-based chemotherapy. However, TNBC cells frequently develop resistance to platinum and experience relapse after drug withdrawal. It is crucial to specifically target and eliminate cisplatin-tolerant cells after platinum administration. Here, it is reported that upregulated N 6-methyladenosine (m6A) modification drives the development of resistance in TNBC cells during cisplatin treatment. Mechanistically, histone deacetylase 2 (HDAC2) mediates delactylation of methyltransferase-like 3 (METTL3), facilitating METTL3 interaction with Wilms'-tumor-1-associated protein and subsequently increasing m6A of transcript-associated DNA damage repair. This ultimately promotes cell survival under cisplatin. Furthermore, pharmacological inhibition of HDAC2 using Tucidinostat can enhance the sensitivity of TNBC cells to cisplatin therapy. This study not only elucidates the biological function of lactylated METTL3 in tumor cells but also highlights its negative regulatory effect on cisplatin resistance. Additionally, it underscores the nonclassical functional mechanism of Tucidinostat as a HDAC inhibitor for improving the efficacy of cisplatin against TNBC.

The m6A reader IGF2BP2 promotes pancreatic cancer progression through the m6A-SLC1A5-mTORC1 axis

BACKGROUND

Pancreatic cancer is a highly malignant digestive tumor. Glutamine metabolism is one of the important sources of tumors. N6-methyladenosine (m6A) modification plays a key role in regulating tumor metabolism and holds promise as a therapeutic target in various cancers, including pancreatic cancer. Disrupting m6A regulation of glutamine metabolism could impair tumor growth, offering potential new therapeutic strategies. However, the functional role of m6A modifications in pancreatic cancer, especially in glutamine metabolism, remains poorly understood.

METHODS

The Cancer Genome Atlas (TCGA) dataset and GEPIA bioinformatics tool were used to identify the relationship between m6A related proteins and the glutamine metabolism-associated genes, respectively. The biological effects of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) were investigated using in vitro and in vivo models. Methylated RNA immunoprecipitation sequencing (MeRIP-seq), MeRIP-PCR and RNA immunoprecipitation (RIP) were used to identify solute carrier family 1 member 5 (SLC1A5) as a direct target of IGF2BP2.

RESULTS

We found that IGF2BP2 expression and SLC1A5 were significantly correlated and both highly expressed in pancreatic cancer could predict poor prognosis in patients with pancreatic cancer. Functionally, silencing IGF2BP2 suppressed tumor growth and also inhibited glutamine uptake by tumor cells. Mechanistically, IGF2BP2 induced the m6A-SLC1A5-mTORC1 axis, facilitating the uptake of glutamine by pancreatic cancer cells and accelerate the progress of pancreatic cancer. Furthermore, silencing IGF2BP2 can enhance the sensitivity of pancreatic cancer to radiotherapy and chemotherapy.

CONCLUSION

Our findings suggest that IGF2BP2 promotes pancreatic cancer by activating the m6A-SLC1A5 -mTORC1 axis. Targeting the m6A machinery, particularly IGF2BP2, offers a novel therapeutic avenue for pancreatic cancer treatment. By disrupting the regulation of glutamine metabolism, we provide new insights into how m6A-based therapies could enhance the efficacy of current treatments and offer hope for improving patient outcomes in this difficult-to-treat cancer.

Emerging importance of m6A modification in liver cancer and its potential therapeutic role

Liver cancer refers to malignant tumors that form in the liver and is usually divided into several types, the most common of which is hepatocellular carcinoma (HCC), which originates in liver cells. Other rare types of liver cancer include intrahepatic cholangiocarcinoma (iCCA). m6A modification is a chemical modification of RNA that usually manifests as the addition of a methyl group to adenine in the RNA molecule to form N6-methyladenosine. This modification exerts a critical role in various biological processes by regulating the metabolism of RNA, affecting gene expression. Recent studies have shown that m6A modification is closely related to the occurrence and development of liver cancer, and m6A regulators can further participate in the pathogenesis of liver cancer by regulating the expression of key genes and the function of specific cells. In this review, we provided an overview of the latest advances in m6A modification in liver cancer research and explored in detail the specific functions of different m6A regulators. Meanwhile, we deeply analyzed the mechanisms and roles of m6A modification in liver cancer, aiming to provide novel insights and references for the search for potential therapeutic targets. Finally, we discussed the prospects and challenges of targeting m6A regulators in liver cancer therapy.

Inhibition of XIST restrains paclitaxel resistance in breast cancer cells by targeting hsa-let-7d-5p/ATG16L1 through regulation of autophagy

Breast cancer is a fatal malignant tumor in women worldwide. The development of paclitaxel resistance remains a challenge. Autophagy is considered to have a significant part in the chemotherapeutic stress mechanism. This study aimed to investigate the function of long non-coding RNA (lncRNA) in breast cancer cell chemoresistance and autophagy. The paclitaxel (PTX)-resistant breast cancer cells were established. The function of X-inactive specific transcript (XIST) was demonstrated using in vitro and in vivo experiments. Transmission electron microscope (TEM) was used to observe autophagy vesicles. Protein and mRNA levels were determined using western blotting and quantitative real time polymerase chain reaction (qRT-PCR). We discovered that autophagic activity was correlated with chemoresistance in PTX-resistant breast cancer cells. In vitro and in vivo studies showed that XIST inhibition reduced cell resistance to paclitaxel, caused autophagy to be suppressed by regulating hsa-let-7d-5p and ATG16L1 expression. Mechanically, threonine protein kinase B (PKB; also known as AKT) - mammalian target of rapamycin (mTOR) pathway was activated when knockdown of XIST, while was reversed by inhibition of hsa-let-7d-5p. Our results verified that XIST played a significant role in developing chemoresistance via mediating autophagy in PTX-resistant breast cancer cells. It may be a potential target for breast cancer treatment strategies.

The role of YTHDF2 in anti-tumor immunity

RNA N 6-methyladenosine (m6A) modification has been identified as the most abundant RNA modification and plays crucial roles in both physiological and pathological processes. YTHDF2 was the first identified reader protein that can recognize m6A modification and recent studies also revealed its ability to bind 5-methylcytidine (m5C) modification. YTHDF2 shows a dual binding capacity to both m6A and m5C, which leads to opposite mRNA outcomes. Multiple studies have highlighted the critical roles of YTHDF2 in tumor development and tumor microenvironment. Emerging findings showed that YTHDF2 plays critical roles in immune regulation, impacting T cell, B cell, NK cell, macrophage, innate/adaptive anti-tumor immune responses, and T-cell based immunotherapy. Inhibitors have been developed to target YTHDF2, which showed potential efficacy in tumor treatment. Herein, we reviewed the molecular mechanism of YTHDF2 and its roles in tumors, immune cells, and tumor microenvironment.

Recent Advances in the Mutual Regulation of m6A Modification and Non-Coding RNAs in Atherosclerosis

Atherosclerosis, a progressive inflammatory disease of the arteries, remains a leading cause of cardiovascular morbidity and mortality worldwide. Recent years have witnessed the pivotal role of N6-methyladenosine (m6A) RNA methylation in regulating various biological processes, including those implicated in atherosclerosis. Current evidence suggested that m6A regulators (writers, erasers, and readers) participated in the modification of multiple non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), thereby affecting their metabolism and functions. Meanwhile, ncRNAs have also emerged as key modulator of m6A regulators expression in turn. Therefore, understanding the mutual regulation between m6A modifications and ncRNAs is of great significance to identify novel therapeutic targets for atherosclerosis and has great clinical application prospects. This review aims to summarize the recent advances in the reciprocal regulation and provide insights into the interaction between m6A modification and ncRNAs in the context of atherosclerosis.

The YTHDC1 reader protein recognizes and regulates the lncRNA MEG3 following its METTL3-mediated m6A methylation: a novel mechanism early during radiation-induced liver injury

While apoptotic cell death is known to be central to the pathogenesis of radiation-induced liver injury (RILI), the mechanistic basis for this apoptotic activity remains poorly understood. N6-methyladenosine (m6A) modifications are the most common form of reversible methylation observed on lncRNAs in eukaryotic cells, with their presence leading to pronounced changes in the activity of a range of biological processes. The degree to which m6A modification plays a role in the induction of apoptotic cell death in response to ionizing radiation (IR) in the context of RILI remains to be established. Here, IR-induced apoptosis was found to significantly decrease the levels of m6A present, with a pronounced decrease in the expression of methyltransferase-like 3 (METTL3) at 2 d post radiation in vitro. From a mechanistic perspective, a methylated RNA immunoprecipitation assay found that lncRNA MEG3 was a major METTL3 target. The expression of MEG3 was upregulated via METTL3-mediated m6A in a process that was dependent on YTHDC1, ultimately reversing the miR-20b-mediated inhibition of BNIP2 expression. Together, these findings demonstrate that the responsivity of METTL3 activity to IR plays a role in IR-induced apoptotic cell death, leading to the reverse of miR-20b-mediated BNIP2 inhibition through the YTHDC1-dependent m6A modification of MEG3, suggesting that this process may play a central role in RILI incidence.

Up-regulation of m6A writer METTL14 inhibits tumorigenesis by suppressing glycolysis in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a common malignant tumor. N6-Methyladenosine (m6A) modification plays an important role in the regulation of glycolysis in tumor cells and may be a potential target for tumor therapy.

METHODS

The role of METTL14, an m6A writer, in CRC was investigated through functional assays including cell viability, colony formation, and glycolysis-related measurements (glucose uptake, lactate production, extracellular acidification rate (ECAR) and oxygen consumption rate (OCR)). The target gene regulated by METTL14 in an m6A-dependent manner was identified using molecular biology techniques. In addition, CRC cells overexpressing METTL14 were subcutaneously injected into mice to verify the regulatory effect of METTL14 on tumor growth in vivo.

RESULTS

Our data suggested that METTL14 was up-regulated in CRC cell lines, and over-expression of METTL14 suppressed cell proliferation and glycolysis. Meanwhile, ATF2 m6A level was significantly up-regulated by over-expression of METTL14, and the binding relationship between ATF2 and METTL14 was further verified. METTL14-m6A regulated ATF2 in CRC cells participates in the regulation of glycolysis. METTL14 also suppressed tumorigenesis of nude mice.

CONCLUSION

Intervention with METTL14 mediated m6A modifications or its associated protein ATF2 may provide new strategies for CRC therapy.

METTL14-mediated m6A modification of LINC00340 exerts oncogenic role in retinoblastoma by regulating Notch signaling pathway

PURPOSE

Retinoblastoma (RB) is a common primary intraocular cancer developed in early childhood. The N6-methyladenosine (m6A) modification of long non-coding RNAs (lncRNAs) have been reported to participate in tumorigenesis. However, the study on the m6A modification of lncRNA in RB is still limited. This study proposed to reveal the role of lncRNA LINC00340 in RB depending on m6A modification.

METHODS

The levels of LINC00340 and methyltransferase-like 14 (METTL14) were detected using qRT-PCR. The effects of LINC00340 interacting with METTL14 on RB cells were assessed by CCK8, colony formation, and flow cytometry assays. The changes of proteins associated with Notch signaling pathway were detected using western blotting. The regulatory mechanism of LINC00340 interacting with METTL14 in RB cells was confirmed by MeRIP, qRT-PCR, and actinomycin D treatment assays.

RESULTS

The expression of LINC00340 and METTL14 in RB samples were elevated, as well as their levels in RB samples showed the positive correlation. Silencing LINC00340 in RB cells could impair RB cell growth and enhance apoptosis via activating Notch signaling pathway, but overexpressing LINC00340 in RB cells showed the opposite effects. In addition, upregulating METTL14 effectively relieved the repressive effects of silencing LINC00340 on RB cells due to METTL14-mediated m6A modification of LINC00340.

CONCLUSIONS

The findings of study reveal that METTL14-mediated m6A modification of LINC00340 exerts oncogenic function in RB via Notch signaling pathway, which may uncover a novel molecular mechanism driving RB progression and identify a potential therapeutic target for RB.

Biological functions of 5-methylcytosine RNA-binding proteins and their potential mechanisms in human cancers

The 5-methylcytosine (m5C) modification is a crucial epigenetic RNA modification, which is involved in the post-transcriptional regulation of genes. It plays an important role in various biological processes, including cell metabolism, growth, apoptosis, and tumorigenesis. By affecting the proliferation, migration, invasion, and drug sensitivity of tumor cells, m5C methylation modification plays a vital part in the initiation and progression of tumors and is closely associated with the poor tumor prognosis. m5C-related proteins are categorized into three functional groups: m5C methyltransferases (m5C writers), m5C demethylases (m5C erasers), and m5C methyl-binding proteins (m5C readers). This paper introduces several common methodologies for detecting m5C methylation; and reviews the molecular structure and biological functions of m5C readers, including ALYREF, YBX1, YBX2, RAD52, YTHDF2, FMRP, and SRSF2. It further summarizes their roles and regulatory mechanisms in tumors, offering novel targets and insights for tumor treatment.

DR6 Augments Colorectal Cancer Cell Growth, Invasion, and Stemness by Activating AKT/NF-κB Pathway

This study aims to elucidate the role and mechanisms of Death Receptor 6 (DR6), a member of the tumor necrosis factor receptor superfamily, in the malignant progression of colorectal cancer (CRC). The association of DR6 expression levels and CRC patient survival was examined using the CRC cohort data from GEPIA database. The functional role of DR6 in CRC cells was investigated by performing loss-of-function and gain-of-function experiments based on CCK-8 proliferation assay, transwell migration and invasion assay, and sphere-forming assays. Xenograft model of CRC cells in nude mouse was established to evaluate the impact of DR6 knockdown on CRC tumorigenesis. Elevated expression of DR6 was correlated with an unfavorable prognosis in CRC patients. In vitro functional assays demonstrated that silencing DR6 considerably suppressed the proliferation, migration, invasion, and stemness of CRC cells, whereas its overexpression showed an opposite effect. DR6 knockdown also attenuated tumor formation of CRC cells in the nude mice. Mechanistically, silencing DR6 reduced the phosphorylation of AKT and NF-κB in CRC cells, and the treatment with an AKT activator (SC79) abrogated the inhibitory effects of DR6 knockdown on the malignant features of CRC cells. Our data suggest that DR6 contributes to the malignant progression of CRC by activating AKT/NF-κB pathway, indicating its clinical potential as a prognostic marker and therapeutic target for CRC.

MRTX1133 attenuates KRASG12D mutated-colorectal cancer progression through activating ferroptosis activity via METTL14/LINC02159/FOXC2 axis

Colorectal cancer (CRC) ranks as the third most commonly diagnosed cancer and the second leading cause of cancer-related deaths worldwide. Studies have shown that CRC patients with KRAS mutations, especially KRASG12D, have an increased risk of metastasis. Emerging evidence indicates that long non-coding RNAs (lncRNAs) are crucial in the carcinogenesis and progression of various cancers, regulating multiple biological processes but the link between KRASG12D mutations and lncRNAs in CRC remains unclear. Therefore, this study was designed to identify a novel lncRNA involved in KRASG12D-mutated CRC and to elucidate its molecular mechanisms. The analysis of differentially expressed lncRNAs in the GSE201412 dataset revealed that LINC02159 was significantly upregulated following treatment with the KRASG12D inhibitor MTRX1133 Data from the GTEx database indicated that LINC02159 is highly expressed in CRC tumour tissues and is associated with better patient outcomes. In vitro and in vivo experiments suggest that LINC02159 acts as a tumour suppressor in CRC progression. Specifically, LINC02159 knockdown negated the inhibitory effects of MRTX1133 on tumourigenesis and its promotive effect on ferroptosis in KRASG12D-mutated CRC cells. LINC02159 expression is regulated by METTL14, with METTL14 knockdown decreasing m6A methylation of LINC02159, leading to its increased expression in CRC cells. Additionally, LINC02159 stabilised FOXC2 expression through de-ubiquitination. Rescue experiments further clarified that the METTL14/LINC02159/FOXC2 signalling axis is crucial for the inhibitory effects of MRTX1133 in KRASG12D-mutated CRC. Our study provides novel insights into the therapeutic potential of MRTX1133 in treating KRASG12D-mutated CRC by identifying a METTL14/LINC02159/FOXC2 signalling axis that mediates drug response. Our findings highlight the importance of understanding the molecular mechanisms of lncRNAs in cancer to develop effective targeted therapies.

Roles of N6-methyladenosine in LncRNA changes and oxidative damage in cadmium-induced pancreatic β-cells

N6-methyladenosine (m6A) modification and LncRNAs play crucial regulatory roles in various pathophysiological processes, yet roles of m6A modification and the relationship between m6A modification and LncRNAs in cadmium-induced oxidative damage of pancreatic β-cells have not been fully elucidated. In this study, m6A agonist entacapone and inhibitor 3-deazadenosine were used to identify the effects of m6A on cadmium-induced oxidative damage as well as LncRNA changes. Our results indicate that elevated levels of m6A modification by entacapone can rescue the cell viability and attenuate the cell apoptosis, while the inhibition levels of m6A modification can exacerbate the cell death. Furthermore, the elevation of m6A modification can recover cadmium-induced oxidative damage to pancreatic β-cells, which characterized as inhibition the ROS accumulation, MDA contents, protein expressions of Nrf2 and Ho-1, while elevation the expressions of Sod1 and Gclc. On the contrary, the reduction levels of m6A modification can exacerbate the cadmium-induced oxidative damage. More importantly, six significantly differentially expressed LncRNAs were selected according to our preliminary sequencing data (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE253072) and there is a clear correlation between the levels of these LncRNAs and m6A modification after cadmium treatment. Interestingly, the intervention of m6A modification levels can significantly affect the levels of these LncRNAs. In detail, the stimulation of m6A modification reversed the changes of cadmium-induced LncRNAs, while the m6A modification inhibition can significantly exacerbate the changes of cadmium-induced LncRNAs. In conclusion, our data revealed critical roles of m6A modification in cadmium-induced LncRNAs and oxidative damage. Our findings point to a new direction for future studies on the molecular mechanisms of pancreatic β-cell damage induced by cadmium.

LINC00882, transcriptionally activated by CEBP-β and post-transcriptionally stabilized by METTL14-mediated m6A modification, exerts tumorigenesis by promoting PABPC1-mediated stabilization of ELK3 mRNA

Breast cancer (BC) is the most common malignant tumor in women, and the majority of BC-related deaths are due to tumor metastasis. There is emerging evidence for the role of long noncoding RNAs (lncRNAs) in tumor progression. Nevertheless, lncRNAs that drive metastasis in patients with BC and the underlying mechanisms of lncRNAs are still largely elusive. In this study, we showed that LINC00882 was highly expressed in metastatic BC tissues, and a receiver operating characteristic (ROC) curve was able to distinguish well between BC cases with lymph node metastasis (LNM) and those without LNM. Functionally, LINC00882 promoted BC invasion and metastasis in vitro and in vivo. Mechanistically, at the transcriptional level, CEBP-β could bind directly to the LINC00882 promoter region and activate its transcription. Moreover, at the posttranscriptional level, m6A modification of LINC00882 mediated by methyltransferase-like 14 (METTL14) promoted its expression via an IGF2BP2-dependent pathway. Furthermore, 514-615 nucleotides of LINC00882 could directly interact with poly (A) binding protein cytoplasmic 1 (PABPC1) and promote the interaction between PABPC1 and ELK3 mRNA, thereby stabilizing ELK3 mRNA and enhancing the ELK3 protein level. E-cadherin expression was suppressed via ELK3-mediated transcription inhibition, subsequently activating epithelial-mesenchymal transition to promote BC metastasis. These results highlight the role of LINC00882 in BC, and LINC00882 may be a diagnostic and therapeutic target for BC.

Potential prognostic and predictive biomarkers: METTL5, METTL7A, and METTL7B expression in gastrointestinal cancers

BACKGROUND

The methyltransferase gene family is known for its diverse biological functions and critical role in tumorigenesis. This study aimed to identify these family genes in common gastrointestinal (GI) cancers using comprehensive methodologies.

METHODS

Gene identification involved analysis of scientific literature and insights from The Cancer Genome Atlas (TCGA) database. RNA sequencing (RNA-seq) data for colon, gastric, pancreatic, esophageal, and liver cancers were collected, processed, and normalized. Differential expression analysis was conducted using R software with the Limma package. Additionally, real-time PCR analysis was performed on 30 tumor and 30 normal tissue samples from patients with colon and gastric cancer. Pathway analysis was conducted via the EnrichR web tool, while survival analysis used Cox regression methods, and biomarker potential was assessed with the pROC package. Prognostic significance was evaluated by examining associations between gene expression, patient survival, and recurrence rates. The study also investigated diagnostic potential through receiver operating characteristic (ROC) analysis, and assessed how small molecules affect gene expression, with implications for drug resistance and sensitivity, analyzed via CCLE and GDSC datasets.

RESULTS

Findings revealed METTL5 overexpression in colon, liver, esophagus, and pancreas cancers, while METTL7A was underexpressed in gastric, esophagus, liver, and colon cancers. METTL7B expression varied, being higher in gastric and esophagus cancers but lower in liver and colon cancers. Enrichment analysis identified pathways related to these genes, and survival analysis associated altered METTL7A and METTL5 expressions with poor prognosis and higher recurrence rates.

CONCLUSIONS

These findings suggest that METTL genes could serve as predictive biomarkers in GI cancers, offering potential implications for patient prognosis and treatment response.

The role of N(6)-methyladenosine (m6a) modification in cancer: recent advances and future directions

N(6)-methyladenosine (m6A) modification is the most abundant and prevalent internal modification in eukaryotic mRNAs. The role of m6A modification in cancer has become a hot research topic in recent years and has been widely explored. m6A modifications have been shown to regulate cancer occurrence and progression by modulating different target molecules. This paper reviews the recent research progress of m6A modifications in cancer and provides an outlook on future research directions, especially the development of molecularly targeted drugs. See also the graphical abstract(Fig. 1).

Divergent roles of m6A in orchestrating brown and white adipocyte transcriptomes and systemic metabolism

N6-methyladenosine (m6A) is among the most abundant mRNA modifications, yet its cell-type-specific regulatory roles remain unclear. Here we show that m6A methyltransferase-like 14 (METTL14) differentially regulates transcriptome in brown versus white adipose tissue (BAT and WAT), leading to divergent metabolic outcomes. In humans and mice with insulin resistance, METTL14 expression differs significantly from BAT and WAT in the context of its correlation with insulin sensitivity. Mettl14-knockout in BAT promotes prostaglandin secretion, improving systemic insulin sensitivity. Conversely, Mettl14-knockout in WAT triggers adipocyte apoptosis and systemic insulin resistance. m6A-seq and RNA-seq integration revealed upregulated prostaglandin biosynthesis pathways in BAT and apoptotic pathways in WAT with Mettl14 deficiency. Stable METTL14-knockout hBAs/hWAs show METTL14-mediated m6A promotes mRNA decay of PTGES2 and CBR1 in hBAs and TRAIL and TNFR1 in hWAs. These data shed light on the ability of m6A to impact metabolism in a cell-type-specific manner with implications for influencing the pathophysiology of metabolic diseases.

Vitamin D receptor regulates methyltransferase like 14 to mitigate colitis-associated colorectal cancer

Colitis-associated colorectal cancer (CAC), a serious complication of ulcerative colitis (UC), is associated with a poor prognosis. The vitamin D receptor (VDR) is recognized for its protective role in UC and CAC through the maintenance of intestinal barrier integrity and the regulation of inflammation. This study demonstrates a significant reduction in m6A-related genes, particularly methyltransferase like 14 (METTL14), in UC and CAC patients and identifies an association between METTL14 and VDR. In the azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced mouse model, vitamin D treatment increases METTL14 expression and reduces tumor burden, while Vdr-knockout mice exhibit lower METTL14 levels and increased tumorigenesis. In vitro, the VDR agonist calcipotriol upregulates METTL14 in NCM460 cells, with this effect attenuated by VDR knockdown. VDR knockdown in DLD-1 colon cancer cells decreases METTL14 expression and promotes proliferation, which is reversed by METTL14 overexpression. Mechanistic studies reveal that VDR regulates METTL14 expression via promoter binding, modulating key target genes such as SOX4, DROSH, and PHLPP2. This study highlights the role of the VDR-METTL14 axis as a protective mechanism in CAC and suggests its potential as a therapeutic target for preventing and treating CAC.

lncRNA POU6F2-AS1 Regulated by KIAA1429 Contributes to Colorectal Cancer Progression in an m6A Modification Manner

Long non-coding RNAs (lncRNAs) are participated in tumourigenesis, including colorectal cancer (CRC). However, the effects and mechanisms of lncRNA POU6F2-AS1 in CRC have not been investigated. KIAA1429 act as a member of N6-methyladenosine (m6A) modification, has been knew as an oncogenic factor in various cancer containing CRC. We focus to investigate the regulation effect of lncRNA POU6F2-AS1, and the mechanism among lncRNA POU6F2-AS1 and KIAA1429 in CRC. The lncRNA POU6F2-AS1 and KIAA1429 levels in CRC tissue samples as well as cells were clarified by qRT-PCR, and their relationship was predicted by bioinformatics, MeRIP and Pearson analysis. Cell survival, migration and invasion were analyzed via EdU, wound healing and Transwell assays after lncRNA POU6F2-AS1 was down-regulated and KIAA1429 was up-regulated. LncRNA POU6F2-AS1 and KIAA1429 were enriched in CRC tissue samples. LncRNA POU6F2-AS1 silencing suppressed CRC cell survival, migration, and invasion, and KIAA1429 overexpression facilitated CRC cell malignancy. KIAA1429 promoted lncRNA POU6F2-AS1 expression via m6A modification. Furthermore, KIAA1429 upregulation reversed the inhibitory effect of lncRNA POU6F2-AS1 interference on the malignant behavior of CRC cells. lncRNA POU6F2-AS1 was modulated by KIAA1429 in the form of m6A modification to regulate the malignant phenotype of CRC, which may provide new insights into the potential application of KIAA1429-m6A-lncRNA POU6F2-AS1-based CRC therapy.

The implications for urological malignancies of non-coding RNAs in the the tumor microenvironment

Urological malignancies are a major global health issue because of their complexity and the wide range of ways they affect patients. There's a growing need for in-depth research into these cancers, especially at the molecular level. Recent studies have highlighted the importance of non-coding RNAs (ncRNAs) – these don't code for proteins but are crucial in controlling genes – and the tumor microenvironment (TME), which is no longer seen as just a background factor but as an active player in cancer progression. Understanding how ncRNAs and the TME interact is key for finding new ways to diagnose and predict outcomes in urological cancers, and for developing new treatments. This article reviews the basic features of ncRNAs and goes into detail about their various roles in the TME, focusing specifically on how different ncRNAs function and act in urological malignancies.

Epigenetics-targeted drugs: current paradigms and future challenges

Epigenetics governs a chromatin state regulatory system through five key mechanisms: DNA modification, histone modification, RNA modification, chromatin remodeling, and non-coding RNA regulation. These mechanisms and their associated enzymes convey genetic information independently of DNA base sequences, playing essential roles in organismal development and homeostasis. Conversely, disruptions in epigenetic landscapes critically influence the pathogenesis of various human diseases. This understanding has laid a robust theoretical groundwork for developing drugs that target epigenetics-modifying enzymes in pathological conditions. Over the past two decades, a growing array of small molecule drugs targeting epigenetic enzymes such as DNA methyltransferase, histone deacetylase, isocitrate dehydrogenase, and enhancer of zeste homolog 2, have been thoroughly investigated and implemented as therapeutic options, particularly in oncology. Additionally, numerous epigenetics-targeted drugs are undergoing clinical trials, offering promising prospects for clinical benefits. This review delineates the roles of epigenetics in physiological and pathological contexts and underscores pioneering studies on the discovery and clinical implementation of epigenetics-targeted drugs. These include inhibitors, agonists, degraders, and multitarget agents, aiming to identify practical challenges and promising avenues for future research. Ultimately, this review aims to deepen the understanding of epigenetics-oriented therapeutic strategies and their further application in clinical settings.

Analysis of METTL14 expression in pancreatic cancer and adjacent tissues and its prognostic value for patient outcomes

This study aims to analyze the differential expression of METTL14 in pancreatic cancer (PC) tissues and adjacent normal tissues, and its correlation with clinical outcomes. According to the inclusion and exclusion criteria, a total of 80 patients diagnosed in our hospital from January 2021 to January 2023 were chosen as research subjects. RTQ-PCR has detected the mRNA level expression of METTL14 in cancer and para-cancerous tissues. Immunohistochemistry was used to detect the protein expression of METTL14 in cancer and para-cancerous tissues. To compare the relationship between METTL14 expression and clinicopathological parameters in different PC patients. Kaplan-Meier survival analysis of the relationship between METTL14 expression in PC tissues and patient survival prognosis. The Multifactor COX model evaluates factors affecting the prognosis of PC. The expression level of METTL14 mRNA in PC tissues was 5.51 ± 0.35 (kDa), and the positive rate of METTL14 protein expression in PC tissues of all patients was 73.75 (59/80). Tumor location (P = 0.012), tumor differentiation degree (P = 0.028), tumor AJCC stage (P = 0.000), and lymph node metastasis (P = 0.000) were significantly related to the positive rate of METTL14 protein expression in PC tissue. Follow-up results showed that among 80 patients, 63 died. The three-year survival rate of the METTL14 positive group was 13.56% (8/59), and the three-year survival rate of the negative group was 42.86% (9/21). The difference in the three-year survival rate between METTL14 positive and negative expression groups was statistically significant (P = 0.031). Multivariate COX regression analysis results showed that METTL14 was positive (OR 2.797, 95% CI 1.233-5.877), tumor AJCC stage II-III (OR 1.628, 95% CI 1.435-3.859) and lymph node metastasis (OR 1.733, 95% CI 1.122-2.372) were substantive risk factors for poor prognosis in patients with PC. METTL14 expression increases in PC tissue, which is related to tumor AJCC stage, tumor differentiation, and lymph node metastasis, and can be evaluated in the survival prognosis of patients with PC.

METTL14 regulates inflammation in ulcerative colitis via the lncRNA DHRS4-AS1/miR-206/A3AR axis

As a chronic inflammatory bowel disease, the pathogenesis of ulcerative colitis (UC) has not been fully elucidated. N6-methyladenosine (m6A) modification, observed in various RNAs, is implicated in inflammatory bowel diseases. Methyltransferase-like 14 (METTL14) is the major subunit of the methyltransferase complex catalyzing m6A modifications. Here, we designated to examine the regulatory effects and mechanisms of METTL14 on long non-coding RNA (lncRNA) during UC progression. METTL14 knockdown decreased cell viability, promoted apoptosis, increased cleaved PARP and cleaved Caspase-3 levels, while reducing Bcl-2 levels. METTL14 knockdown also led to a significant increase in NF-κB pathway activation and inflammatory cytokine production in the Caco-2 cells treated with TNF-α. Moreover, the suppression of METTL14 aggravated colonic damage and inflammation in our dextran sulfate sodium (DSS)-induced murine colitis model. METTL14 silencing suppressed DHRS4-AS1 expression by reducing the m6A modification of DHRS4-AS1 transcripts. Furthermore, DHRS4-AS1 mitigated inflammatory injury by targeting the miR-206/adenosine A3 receptor (A3AR) axis. DHRS4-AS1 overexpression counteracted the enhancing impact of METTL14 knockdown on TNF-α-induced inflammatory injury in Caco-2 cells. In conclusion, our findings suggest that METTL14 protects against colonic inflammatory injury in UC via regulating the DHRS4-AS1/miR-206/A3AR axis, thus representing a potential therapeutic target for UC.

N6-methyladenosine and its epitranscriptomic effects on hematopoietic stem cell regulation and leukemogenesis

N6-methyladenosine (m6A) RNA modification orchestrates cellular epitranscriptome through tuning the homeostasis of transcript stability, translation efficiency, and the transcript affinity toward RNA-binding proteins (RBPs). An aberrant m6A deposition on RNA can lead toward oncogenic expression profile (mRNA), impaired mitochondrial metabolism (mtRNA), and translational suppression (rRNA) of tumor suppressor genes. In addition, non-coding RNAs (ncRNAs), such as X-inactive specific transcript (XIST), miRNAs, and α-ketoglutarate-centric metabolic transcripts are also regulated by the m6A epitranscriptome. Notably, recent studies had uncovered a myriad of m6A-modified transcripts the center of hematopoietic stem cell (HSC) regulation, in which m6A modification act as a context dependent switch to the on and off of hematopoietic stem cell (HSC) maintenance, lineage commitment and terminal differentiation. In this review, we sequentially unfold the m6A mediated epithelial-to-hematopoietic transition in progenitor blood cell production, lymphocytic lineage expansion (T cells, B cells, NK cells, and non-NK ILCs), and the m6A crosstalk with the onco-metabolic prospects of leukemogenesis. Together, an encompassing body of evidence highlighted the emerging m6A significance in the regulation of HSC biology and leukemogenesis.

RNA modifications in long non-coding RNAs and their implications in cancer biology

Long non-coding RNAs (lncRNAs) represent the most diverse class of RNAs in cells and play crucial roles in maintaining cellular functions. RNA modifications, being a significant factor in regulating RNA biology, have been found to be extensively present in lncRNAs and exert regulatory effects on their behavior and biological functions. Most common types of RNA modifications in lncRNAs include N6-methyladenosine (m6A), 5-methylcytosine (m5C), and N1-methyladenosine (m1A). In this review, we summarize the major RNA modification types associated with lncRNAs, the regulatory roles of each modification, and the implications of modified lncRNAs in tumorigenesis and development. By examining these aspects, we aim to provide insights into the role of RNA modifications in lncRNAs and their potential impact on cancer biology.

Propofol attenuates prostate cancer progression by upregulating TRHDE-AS1 expression, and METTL14 could mediate its m6A modification

Propofol has become a microtubule-stabilizing drug for prostate cancer (PC) therapy, but propofol resistance impairs the therapeutic effect. This study aimed to explore the regulatory mechanism of propofol in the pathogenesis of PC through mechanisms involving N6-methyladenosine (m6A) modification. The changes in PC cell malignancy were evaluated by means of transwell, cell counting kit 8 (CCK-8), western blotting and tumour xenograft model assays. Long noncoding RNA TRHDE-AS1 and m6A methyltransferase METTL14 expression levels were determined via reverse transcription quantitative polymerase chain reaction (RT-qPCR). The m6A modification of TRHDE-AS1 which was mediated by METTL14 was confirmed by conducting methylated RNA immunoprecipitation (MeRIP) assay. We observed that propofol (200 μM) inhibited PC cell malignancy in vivo and in vitro, elucidating that it impaired cell proliferation, migration and tumour growth but induced apoptosis. TRHDE-AS1 expression was observed to be lower in PC cells and tissues, and propofol induced TRHDE-AS1 upregulation in PC cells. Propofol was capable of reversing the tumour-promoting effect of TRHDE-AS1 knockdown in PC cells. Additionally, METTL14 was upstream of TRHDE-AS1 to induce m6A modification of TRHDE-AS1 in PC cells. Collectively, our results show that propofol prevents PC progression by upregulating TRHDE-AS1 expression and METTL14 is involved in the m6A modification of TRHDE-AS1. These findings suggest that TRHDE-AS1 may be a potential therapeutic target for the improvement of propofol's therapeutic effect.

The interaction between m6A modification and noncoding RNA in tumor microenvironment on cancer progression

Cancer development is thought to be closely related to aberrant epigenetic regulation, aberrant expression of specific non-coding RNAs (ncRNAs), and tumor microenvironment (TME). The m6A methylation is one of the most abundant RNA modifications found in eukaryotes, and it can determine the fate of RNA at the post-transcriptional level through a variety of mechanisms, which affects important biological processes in the organism. The m6A methylation modification is involved in RNA processing, regulation of RNA nuclear export or localisation, RNA degradation and RNA translation. This process affects the function of mRNAs and ncRNAs, thereby influencing the biological processes of cancer cells. TME accelerates and promotes cancer generation and progression during tumor development. The m6A methylation interacting with ncRNAs is closely linked to TME formation. Mutual regulation and interactions between m6A methylation and ncRNAs in TME create complex networks and mediate the progression of various cancers. In this review, we will focus on the interactions between m6A modifications and ncRNAs in TME, summarising the molecular mechanisms by which m6A interacts with ncRNAs to affect TME and their roles in the development of different cancers. This work will help to deepen our understanding of tumourigenesis and further explore new targets for cancer therapy.

Colon Cancer-Derived Exosomal LncRNA-XIST Promotes M2-like Macrophage Polarization by Regulating PDGFRA

Colon cancer ranks second in overall cancer-related deaths and poses a serious risk to human life and health. In recent years, exosomes are believed to play an important and significant role in cancer, especially tumor-derived exosomes (TDEs). Previous studies have highlighted the pivotal role of exosomes in tumor development, owing to their ability to mediate communication between tumor cells and macrophages, induce macrophage M2 polarization, and facilitate the progression of tumorigenesis. In this study, we revealed that colon cancer-derived exosomes promoted M2-like macrophage polarization. Moreover, exosome-induced M2-like macrophages, in turn, promoted the proliferation, migration, and invasion abilities of colon cancer cells. Specifically, CT26- and HCT116-derived exosomes led to the activation of AKT, ERK, and STAT3/6 signaling pathways in THP-1(Mφ) cells. Furthermore, our findings showed that colon cancer-derived exosomes secreted lncXIST to sponge miR-17-5p, which, in turn, promoted the expression of PDGFRA, a common gene found in all three signaling pathways, to facilitate M2-like macrophage polarization. Dual-luciferase reporter assays confirmed the binding relationship between lncXIST and miR-17-5p, as well as miR-17-5p and PDGFRA. Collectively, our results highlight the novel role of lncXIST in facilitating macrophage polarization by sponging miR-17-5p and regulating PDGFRA expression.

Modulation of host N6-methyladenosine modification by gut microbiota in colorectal cancer

As a research hotspot in the field of molecular biology, N6-methyladenosine (m6A) modification has made progress in the treatment of colorectal cancer (CRC), leukemia and other cancers. Numerous studies have demonstrated that the tumour microenvironment (TME) regulates the level of m6A modification in the host and activates a series of complex epigenetic signalling pathways through interactions with CRC cells, thus affecting the progression and prognosis of CRC. However, with the diversity in the composition of TME factors, this action is reciprocal and complex. Encouragingly, some studies have experimentally revealed that the intestinal flora can alter CRC cell proliferation by directly acting on m6A and thereby altering CRC cell proliferation. This review summarizes the data, supporting the idea that the intestinal flora can influence host m6A levels through pathways such as methyl donor metabolism and thus affect the progression of CRC. We also review the role of m6A modification in the diagnosis, treatment, and prognostic assessment of CRC and discuss the current status, limitations, and potential clinical value of m6A modification in this field. We propose that additional in-depth research on m6A alterations in CRC patients and their TME-related targeted therapeutic issues will lead to better therapeutic outcomes for CRC patients.

Genome-wide CRISPR screening identifies the pivotal role of ANKRD42 in colorectal cancer metastasis through EMT regulation

Colorectal cancer (CRC), a pervasive and lethal malignancy of gastrointestinal cancer, imposes significant challenges due to the occurrence of distant metastasis in advanced stages. Understanding the intricate regulatory mechanisms driving CRC distant metastasis is of paramount importance. CRISPR-Cas9 screening has emerged as a powerful tool for investigating tumor initiation and progression. However, its application in studying CRC distant metastasis remains largely unexplored. To establish a model that faithfully recapitulates CRC liver metastasis in patients, we developed an in vivo genome-wide CRISPR-Cas9 screening approach using a spleen-injected liver metastasis mouse model. Through comprehensive screening of a whole-genome sgRNA library, we identified ANKRD42 as a pivotal regulatory gene facilitating CRC liver metastasis. Analysis of the TCGA database and our clinical cohorts unveiled heightened ANKRD42 expression in metastases. At the cellular level, the attenuation of ANKRD42 impaired the migration and invasion processes of tumor cells. In vivo experiments further validated these observations, highlighting the diminished liver metastatic capacity of tumor cells upon ANKRD42 knockdown. To unravel the specific mechanisms by which ANKRD42 regulates CRC distant metastasis, we leveraged patient-derived organoid (PDO) models. Depleting ANKRD42 in PDOs sourced from liver metastases precipitated the downregulation of pivotal genes linked to epithelial-mesenchymal transition (EMT), including CDH2 and SNAI2, thereby effectively suppressing tumor metastasis. This study not only establishes a conceptual framework but also identifies potential therapeutic avenues for advanced-stage distant metastasis in CRC patients.

The m6A methyltransferase METTL14 promotes cell proliferation via SETBP1-mediated activation of PI3K-AKT signaling pathway in myelodysplastic neoplasms

N6-methyladenosine (m6A) is the most prevalent epitranscriptomic modification in mammalian mRNA. Recent studies have revealed m6A is involved in the pathogenesis of various malignant tumors including hematologic neoplasms. Nevertheless, the specific roles of m6A modification and m6A regulators in myelodysplastic neoplasms (MDS) remain poorly understood. Herein, we demonstrated that m6A level and the expression of m6A methyltransferase METTL14 were elevated in MDS patients with bone marrow blasts ≥5%. Additionally, m6A level and METTL14 expression were upregulated as the disease risk increased and significantly associated with adverse clinical outcomes. Knockdown of METTL14 inhibited cell proliferation and colony formation ability of MDS cells. Moreover, in vivo experiments showed METTL14 knockdown remarkably reduced tumor burden and prolonged the survival of mice. Mechanistically, METTL14 facilitated the m6A modification of SETBP1 mRNA by formation of METTL3-METTL14 complex, leading to increased stabilization of SETBP1 mRNA and subsequent activation of the PI3K-AKT signaling pathway. Overall, this study elucidated the involvement of the METTL14/m6A/SETBP1/PI3K-AKT signaling axis in MDS, highlighting the therapeutic potential of targeting METTL3-METTL14 complex-mediated m6A modification for MDS therapy.

METTL14-mediated N6-methyladenosine modification of TCP1 mRNA promotes acute myeloid leukemia progression

BACKGROUND

Acute myeloid leukemia (AML) is a prevalent hematologic malignancy characterized by a steady rise in morbidity and mortality rates over time. The upregulation of methyltransferase-like 14 (METTL14) expression in AML has been identified; however, its specific contributions to AML progression and underlying molecular mechanisms have yet to be elucidated.

METHOD

METTL14-bound mRNAs were predicted using bioinformatics methods, analyzed, and screened to identify T-complex protein 1 (TCP1). The regulatory impact of METTL14 on TCP1 was observed. TCP1 expression in AML clinical samples was assessed using quantitative real-time PCR and western blot analysis. The involvement of TCP1 in AML malignant progression was assessed through in vitro and in vivo functional assays. The String database was utilized for predicting proteins that interact with TCP1, while western blot assays and immunoprecipitation were employed to validate the associated signaling pathways.

RESULTS

METTL14 overexpression upregulates TCP1 expression in AML cells. AML patients exhibit high levels of TCP1 expression. Elevated TCP1 levels in HL60 and U937 cells in vitro lead to increased proliferation, migration, invasion, and inhibition of apoptosis, while in vivo, it accelerates AML proliferation and tumorigenesis. Mechanistically, METTL14 modulates AML progression by influencing TCP1 transcript stability via m6A methylation, thereby regulating TCP1 expression. Additionally, PPP2R2C potentially serves as a crucial functional target of TCP1 implicated in the malignant progression of AML.

CONCLUSION

Upregulation of TCP1 expression in AML through METTL14-mediated m6A modification accelerates the malignant progression of the disease. Therefore, targeting the m6A modification of TCP1 could be a potential therapeutic strategy to enhance the treatment of AML.

Zinc finger protein 180 induces an apoptotic phenotype by activating METTL14 transcriptional activity in colorectal cancer

Zinc finger protein 180 (ZNF180) is a multifunctional protein that interacts with nucleic acids and regulates various cellular processes; however, the function of ZNF180 in colorectal cancer (CRC) remains unclear. The present study investigated the role and function of ZNF180 in CRC, and aimed to reveal the underlying molecular mechanism. The results revealed that ZNF180 was downregulated in CRC tissues and was associated with a good prognosis in patients with CRC. Additionally, the expression of ZNF180 was downregulated by methylation in CRC. In vivo and in vitro experiments revealed that ZNF180 overexpression was functionally associated with the inhibition of cell proliferation and the induction of apoptosis. Mechanistically, chromatin immunoprecipitation‑PCR and luciferase assays demonstrated that ZNF180 markedly regulated the transcriptional activity of methyltransferase 14, N6‑adenosine‑methyltransferase non‑catalytic subunit (METTL14) by directly binding to and activating its promoter region. Simultaneous overexpression of ZNF180 and knockdown of METTL14 indicated that the reduction of METTL14 could suppress the effects of ZNF180 on the induction of apoptosis. Clinically, the present study observed a significant positive correlation between ZNF180 and METTL14 expression levels, and low expression of ZNF180 and METTL14 predicted a poor prognosis in CRC. Overall, these findings revealed a novel mechanism by which the ZNF180/METTL14 axis may modulate apoptosis and cell proliferation in CRC. This evidence suggests that this axis may serve as a prognostic biomarker and therapeutic target in patients with CRC.

N6-Methyladenosine-mediated phase separation suppresses NOTCH1 expression and promotes mitochondrial fission in diabetic cardiac fibrosis

BACKGROUND

N6-methyladenosine (m6A) modification of messenger RNA (mRNA) is crucial for liquid-liquid phase separation in mammals. Increasing evidence indicates that liquid-liquid phase separation in proteins and RNAs affects diabetic cardiomyopathy. However, the molecular mechanism by which m6A-mediated phase separation regulates diabetic cardiac fibrosis remains elusive.

METHODS

Leptin receptor-deficient mice (db/db), cardiac fibroblast-specific Notch1 conditional knockout (POSTN-Cre × Notch1flox/flox) mice, and Cre mice were used to induce diabetic cardiac fibrosis. Adeno-associated virus 9 carrying cardiac fibroblast-specific periostin (Postn) promoter-driven small hairpin RNA targeting Alkbh5, Ythdf2, or Notch1, and the phase separation inhibitor 1,6-hexanediol were administered to investigate their roles in diabetic cardiac fibrosis. Histological and biochemical analyses were performed to determine how Alkbh5 and Ythdf2 regulate Notch1 expression in diabetic cardiac fibrosis. NOTCH1 was reconstituted in ALKBH5- and YTHDF2-deficient cardiac fibroblasts and mouse hearts to study its effects on mitochondrial fission and diabetic cardiac fibrosis. Heart tissue samples from patients with diabetic cardiomyopathy were used to validate our findings.

RESULTS

In mice with diabetic cardiac fibrosis, decreased Notch1 expression was accompanied by high m6A mRNA levels and mitochondrial fission. Fibroblast-specific deletion of Notch1 enhanced mitochondrial fission and cardiac fibroblast proliferation and induced diabetic cardiac fibrosis in mice. Notch1 downregulation was associated with Alkbh5-mediated m6A demethylation in the 3'UTR of Notch1 mRNA and elevated m6A mRNA levels. These elevated m6A levels in Notch1 mRNA markedly enhanced YTHDF2 phase separation, increased the recognition of m6A residues in Notch1 mRNA by YTHDF2, and induced Notch1 degradation. Conversely, epitranscriptomic downregulation rescues Notch1 expression, resulting in the opposite effects. Human heart tissues from patients with diabetic cardiomyopathy were used to validate the findings in mice with diabetic cardiac fibrosis.

CONCLUSIONS

We identified a novel epitranscriptomic mechanism by which m6A-mediated phase separation suppresses Notch1 expression, thereby promoting mitochondrial fission in diabetic cardiac fibrosis. Our findings provide new insights for the development of novel treatment approaches for patients with diabetic cardiac fibrosis.

Reading the m6A-encoded epitranscriptomic information in development and diseases

N6-methyladenosine (m6A) represents the most prevalent internal and reversible modification on RNAs. Different cell types display their unique m6A profiles, which are determined by the functions of m6A writers and erasers. M6A modifications lead to different outcomes such as decay, stabilization, or transport of the RNAs. The m6A-encoded epigenetic information is interpreted by m6A readers and their interacting proteins. M6A readers are essential for different biological processes, and the defects in m6A readers have been discovered in diverse diseases. Here, we review the latest advances in the roles of m6A readers in development and diseases. These recent studies not only highlight the importance of m6A readers in regulating cell fate transitions, but also point to the potential application of drugs targeting m6A readers in diseases.

RNA m6A modification in ferroptosis: implications for advancing tumor immunotherapy

The pursuit of innovative therapeutic strategies in oncology remains imperative, given the persistent global impact of cancer as a leading cause of mortality. Immunotherapy is regarded as one of the most promising techniques for systemic cancer therapies among the several therapeutic options available. Nevertheless, limited immune response rates and immune resistance urge us on an augmentation for therapeutic efficacy rather than sticking to conventional approaches. Ferroptosis, a novel reprogrammed cell death, is tightly correlated with the tumor immune environment and interferes with cancer progression. Highly mutant or metastasis-prone tumor cells are more susceptible to iron-dependent nonapoptotic cell death. Consequently, ferroptosis-induction therapies hold the promise of overcoming resistance to conventional treatments. The most prevalent post-transcriptional modification, RNA m6A modification, regulates the metabolic processes of targeted RNAs and is involved in numerous physiological and pathological processes. Aberrant m6A modification influences cell susceptibility to ferroptosis, as well as the expression of immune checkpoints. Clarifying the regulation of m6A modification on ferroptosis and its significance in tumor cell response will provide a distinct method for finding potential targets to enhance the effectiveness of immunotherapy. In this review, we comprehensively summarized regulatory characteristics of RNA m6A modification on ferroptosis and discussed the role of RNA m6A-mediated ferroptosis on immunotherapy, aiming to enhance the effectiveness of ferroptosis-sensitive immunotherapy as a treatment for immune-resistant malignancies.

Copper homeostasis and cuproptosis in gynecological cancers

Copper (Cu) is an essential trace element involved in a variety of biological processes, such as antioxidant defense, mitochondrial respiration, and bio-compound synthesis. In recent years, a novel theory called cuproptosis has emerged to explain how Cu induces programmed cell death. Cu targets lipoylated enzymes in the tricarboxylic acid cycle and subsequently triggers the oligomerization of lipoylated dihydrolipoamide S-acetyltransferase, leading to the loss of Fe-S clusters and induction of heat shock protein 70. Gynecological malignancies including cervical cancer, ovarian cancer and uterine corpus endometrial carcinoma significantly impact women's quality of life and even pose a threat to their lives. Excessive Cu can promote cancer progression by enhancing tumor growth, proliferation, angiogenesis and metastasis through multiple signaling pathways. However, there are few studies investigating gynecological cancers in relation to cuproptosis. Therefore, this review discusses Cu homeostasis and cuproptosis while exploring the potential use of cuproptosis for prognosis prediction as well as its implications in the progression and treatment of gynecological cancers. Additionally, we explore the application of Cu ionophore therapy in treating gynecological malignancies.

METTL protein family: focusing on the occurrence, progression and treatment of cancer

Methyltransferase-like protein is a ubiquitous enzyme-like protein in the human body, with binding domains for nucleic acids, proteins and other small molecules, and plays an important role in a variety of biological behaviours in normal organisms and diseases, characterised by the presence of a methyltransferase-like structural domain and a structurally conserved SAM-binding domain formed by the seven-stranded β-fold structure in the center of the protein. With the deepening of research, the METTL protein family has been found to be abnormally expressed in a variety of tumor diseases, and the clarification of its relationship with tumor diseases can be used as a molecular therapeutic target and has an important role in the prognosis of tumors. In this paper, we review the structure, biological process, immunotherapy, drug-targeted therapy, and markers of the METTL protein family to provide new ideas for the diagnosis and treatment of tumors.

Regulatory effect of N6-methyladenosine on tumor angiogenesis

Previous studies have demonstrated that genetic alterations governing epigenetic processes frequently drive tumor development and that modifications in RNA may contribute to these alterations. In the 1970s, researchers discovered that N6-methyladenosine (m6A) is the most prevalent form of RNA modification in advanced eukaryotic messenger RNA (mRNA) and noncoding RNA (ncRNA). This modification is involved in nearly all stages of the RNA life cycle. M6A modification is regulated by enzymes known as m6A methyltransferases (writers) and demethylases (erasers). Numerous studies have indicated that m6A modification can impact cancer progression by regulating cancer-related biological functions. Tumor angiogenesis, an important and unregulated process, plays a pivotal role in tumor initiation, growth, and metastasis. The interaction between m6A and ncRNAs is widely recognized as a significant factor in proliferation and angiogenesis. Therefore, this article provides a comprehensive review of the regulatory mechanisms underlying m6A RNA modifications and ncRNAs in tumor angiogenesis, as well as the latest advancements in molecular targeted therapy. The aim of this study is to offer novel insights for clinical tumor therapy.

The landscape of epigenetic regulation and therapeutic application of N6-methyladenosine modifications in non-coding RNAs

RNA N6-methyladenosine (m6A) methylation is the most abundant and conserved RNA modification in eukaryotes. It participates in the regulation of RNA metabolism and various pathophysiological processes. Non-coding RNAs (ncRNAs) are defined as small or long transcripts which do not encode proteins and display numerous biological regulatory functions. Similar to mRNAs, m6A deposition is observed in ncRNAs. Studying RNA m6A modifications on ncRNAs is of great importance specifically to deepen our understanding of their biological roles and clinical implications. In this review, we summarized the recent research findings regarding the mutual regulation between RNA m6A modification and ncRNAs (with a specific focus on microRNAs, long non-coding RNAs, and circular RNAs) and their functions. We also discussed the challenges of m6A-containing ncRNAs and RNA m6A as therapeutic targets in human diseases and their future perspective in translational roles.

Ouabain-mediated downregulation of ALKBH5 and IGF2BP2 inhibits the malignant progression of DLBCL

m6A modification is a crucial epigenetic regulatory mechanism in diffuse large B-cell lymphoma (DLBCL). Low-dose cardiotonic drugs have been shown to induce apoptosis in DLBCL cells through epigenetic modulation. However, the involvement of the cardiotonic drug ouabain in the malignant progression of DLBCL remains unclear. Our study revealed that ouabain indeed contributes to the malignant progression of DLBCL through m6A modification. Through qPCR analysis, we observed a negative correlation between ouabain concentration and the expression levels of the demethylase ALKBH5 and the m6A-binding protein IGF2BP2 in DLBCL cells. Furthermore, high expression levels of ALKBH5 and IGF2BP2 were identified in both the GEO database and DLBCL patient tissue samples. Notably, elevated ALKBH5 and IGF2BP2 promoted cell proliferation both in vitro and in vivo. Inhibition of their expression rendered DLBCL cells more sensitive to ouabain treatment, resulting in significant suppression of cell proliferation, G1/S phase cell cycle arrest, and increased apoptosis. In summary, our results clarify that the demethylase ALKBH5 and the m6A-binding protein IGF2BP2 are involved in the malignant progression of DLBCL, and that the cardiotonic drug ouabain can inhibit the proliferation of DLBCL cells by inhibiting the expression of ALKBH5 and IGF2BP2, which provides new insights into the targeted treatment of DLBCL.

Investigating the role of senescence biomarkers in colorectal cancer heterogeneity by bulk and single-cell RNA sequencing

Colorectal cancer (CRC) is one of most common tumors worldwide, causing a prominent global health burden. Cell senescence is a complex physiological state, characterized by proliferation arrest. Here, we investigated the role of cellular senescence in the heterogeneity of CRC. Based on senescence-associated genes, CRC samples were classified into different senescence patterns with different survival, cancer-related biological processes and immune cell infiltrations. A senescence-related model was then developed to calculate the senescence-related score to comprehensively explore the heterogeneity of each CRC sample such as stromal activities, immunoreactivities and drug sensitivity. Single-cell analysis revealed there were different immune cell infiltrations between low and high senescence-related model genes enrichment groups, which was confirmed by multiplex immunofluorescence staining. Pseudotime analysis indicated model genes play a pivotal role in the evolution of B cells. Besides, intercellular communication modeled by NicheNet showed tumor cells with higher enrichment of senescence-related model genes highly expressed CXCL2/3 and CCL3/4, which attracted immunosuppressive cell infiltration and promoted tumor metastasis. Finally, top 6 hub genes were identified from senescence-related model genes by PPI analysis. And RT-qPCR revealed the expression differences of hub genes between normal and CRC cell lines, indicating to some extent the clinical practicability of senescence-related model. To sum up, our study explores the impact of cellular senescence on the prognosis, TME and treatment of CRC based on senescence patterns. This provides a new perspective for CRC treatment.

The Role of m6A Methylation in Tumor Immunity and Immune-Associated Disorder

N6-methyladenosine (m6A) represents the most prevalent and significant internal modification in mRNA, with its critical role in gene expression regulation and cell fate determination increasingly recognized in recent research. The immune system, essential for defense against infections and maintaining internal stability through interactions with other bodily systems, is significantly influenced by m6A modification. This modification acts as a key post-transcriptional regulator of immune responses, though its effects on different immune cells vary across diseases. This review delineates the impact of m6A modification across major system-related cancers-including those of the respiratory, digestive, endocrine, nervous, urinary reproductive, musculoskeletal system malignancies, as well as acute myeloid leukemia and autoimmune diseases. We explore the pathogenic roles of m6A RNA modifications within the tumor immune microenvironment and the broader immune system, highlighting how RNA modification regulators interact with immune pathways during disease progression. Furthermore, we discuss how the expression patterns of these regulators can influence disease susceptibility to immunotherapy, facilitating the development of diagnostic and prognostic models and pioneering new therapeutic approaches. Overall, this review emphasizes the challenges and prospective directions of m6A-related immune regulation in various systemic diseases throughout the body.

A A, Suchita J, Gacche RN. Cancer metastases: Tailoring the targets

Metastasis is an intricate and formidable pathophysiological process encompassing the dissemination of cancer cells from the primary tumour body to distant organs. It stands as a profound and devastating phenomenon that constitutes the primary driver of cancer-related mortality. Despite great strides of advancements in cancer research and treatment, tailored anti-metastasis therapies are either lacking or have shown limited success, necessitating a deeper understanding of the intrinsic elements driving cancer invasiveness. This comprehensive review presents a contemporary elucidation of pivotal facets within the realm of cancer metastasis, commencing with the intricate processes of homing and invasion. The process of angiogenesis, which supports tumour growth and metastasis, is addressed, along with the pre-metastatic niche, wherein the primary tumour prepares for a favorable microenvironment at distant sites for subsequent metastatic colonization. The landscape of metastasis-related genetic and epigenetic mechanisms, involvement of metastasis genes and metastasis suppressor genes, and microRNAs (miRNA) are also discussed. Furthermore, immune modulators' impact on metastasis and their potential as therapeutic targets are addressed. The interplay between cancer cells and the immune system, including immune evasion mechanisms employed by metastatic cells, is discussed, highlighting the importance of targeting immune modulation in arresting metastatic progression. Finally, this review presents promising treatment opportunities derived from the insights gained into the mechanisms of metastasis. Identifying novel therapeutic targets and developing innovative strategies to disrupt the metastatic cascade holds excellent potential for improving patient outcomes and ultimately reducing cancer-related mortality.