LCAT3, a novel m6A-regulated long non-coding RNA, plays an oncogenic role in lung cancer via binding with FUBP1 to activate c-MYC

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.

FUBP1 in human cancer: Characteristics, functions, and potential applications

Far upstream element-binding protein 1 (FUBP1) is a single-stranded nucleic acid-binding protein that binds to the Far Upstream Element (FUSE) sequence and is involved in important biological processes, including DNA transcription, RNA biogenesis, and translation. Recent studies have highlighted the significance of aberrant expression or mutations in FUBP1 in the development of various tumors, with FUBP1 overexpression often indicating oncogenic roles in different tumor types. However, it is worth noting that recent research has discovered its tumor-suppressive role in cancer, which is not yet fully understood and appears to be tissue- or context-dependent. This review summarizes the association between FUBP1 and diverse cancers and discusses the functions of FUBP1 in cancer. In addition, this review proposes potential clinical implications and outlines future research directions to pave the way for the development of targeted therapeutic strategies focusing on FUBP1.

ARMCX1 inhibits lung adenocarcinoma progression by recruiting FBXW7 for c-Myc degradation

BACKGROUND

Armadillo Repeat Containing X-Linked 1 (ARMCX1), a member of the ARM Repeat X-linked protein family, exerts inhibitory function in various tumors. However, its biological role in lung adenocarcinoma (LUAD) and the underlying molecular mechanisms require further exploration.

METHODS

LUAD tissue microarrays and bioinformatic databases were used to evaluate the relationship between ARMCX1 and clinicopathological features. The influence of ARMCX1 on LUAD cell proliferation, migration, and invasion in vitro was determined by colony formation, CCK-8, EdU incorporation, cell cycle, wound healing, and Transwell assays. The impact of ARMCX1 on LUAD cell growth and metastasis in vivo was determined by subcutaneously transplanted tumor and pulmonary metastasis assays. Western blot, immunoprecipitation, immunofluorescence, cycloheximide, and proteasome inhibitor assays were finally conducted to explore the potential underlying molecular mechanisms.

RESULTS

ARMCX1 expression was downregulated in clinical LUAD samples due to which patient prognoses were poor. Functional experiments indicated that ARMCX1 overexpression inhibited the growth and metastasis of LUAD cells in vitro and in vivo. The molecular mechanism suggested that ARMCX1 recruits the E3 ubiquitin ligase FBXW7 for mediating ubiquitinated degradation of c-Myc, suppressing its nuclear accumulation, and ultimately inactivating cell cycle and epithelial-mesenchymal transition (EMT) signals.

CONCLUSION

ARMCX1 inhibits LUAD cell proliferation and metastasis by interacting with c-Myc and enhancing its ubiquitination and degradation. Consequently, it can act as a tumor suppressor in this disease. These results suggest that ARMCX1 is a potential target in the treatment of LUAD.

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.

Akkermansia muciniphila-derived pentadecanoic acid enhances oxaliplatin sensitivity in gastric cancer by modulating glycolysis

Accumulating evidence has proved the close association between alterations in gut microbiota and resistance to chemotherapeutic drugs. However, the potential roles of gut microbiota in regulating oxaliplatin sensitivity in gastric cancer (GC) have not been investigated before. We first found that antibiotic treatment diminished the therapeutic efficacy of oxaliplatin in a GC mouse model. Importantly, this effect could be transmitted to germ-free mice via fecal microbiota transplantation, indicating a potential role of gut microbiota modulation in oxaliplatin efficacy. Further, metagenomics data showed that Akkermansia muciniphila (A. muciniphila) ranked first among the bacterial species with decreased relative abundances after antibiotic treatment. Metabolically active A. muciniphila promotes oxaliplatin efficacy. As shown by metabolomics analysis, the metabolic pattern of gut microbiota was disrupted with significantly downregulated levels of pentadecanoic acid (PEA), and the use of PEA significantly promoted oxaliplatin efficacy. Mechanistically, FUBP1 positively regulated aerobic glycolysis of GC cells to hinder the therapeutic efficacy of oxaliplatin. A. muciniphila-derived PEA functioned as an inhibitory factor of glycolysis by directly antagonizing the activity of FUBP1, which potentiated GC responses to oxaliplatin. Our research suggested a key role for intestinal A. muciniphila and its metabolite PEA in promoting oxaliplatin efficacy, thus providing a new perspective for probiotic and prebiotic intervention in GC patients during chemotherapy.

N6-methyladenosine RNA modifications: a potential therapeutic target for AML

N6-methyladenosine (m6A) RNA modification has recently emerged as an essential regulator of normal and malignant hematopoiesis. As a reversible epigenetic modification found in messenger RNAs and non-coding RNAs, m6A affects the fate of the modified RNA molecules. It is essential in most vital bioprocesses, contributing to cancer development. Here, we review the up-to-date knowledge of the pathological functions and underlying molecular mechanism of m6A modifications in normal hematopoiesis, leukemia pathogenesis, and drug response/resistance. At last, we discuss the critical role of m6A in immune response, the therapeutic potential of targeting m6A regulators, and the possible combination therapy for AML.

Unraveling the molecular landscape of osteoarthritis: A comprehensive review focused on the role of non-coding RNAs

Osteoarthritis (OA) poses a significant global health challenge, with its prevalence anticipated to increase in the coming years. This review delves into the emerging molecular biomarkers in OA pathology, focusing on the roles of various molecules such as metabolites, noncoding RNAs (ncRNAs), including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Advances in omics technologies have transformed biomarker identification, enabling comprehensive analyses of the complex pathways involved in OA pathogenesis. Notably, ncRNAs, especially miRNAs and lncRNAs, exhibit dysregulated expression patterns in OA, presenting promising opportunities for diagnosis and therapy. Additionally, the intricate interplay between epigenetic modifications and OA progression highlights the regulatory role of epigenetics in gene expression dynamics. Genome-wide association studies have pinpointed key genes undergoing epigenetic changes, providing insights into the inflammatory processes and chondrocyte hypertrophy typical of OA. Understanding the molecular landscape of OA, including biomarkers and epigenetic mechanisms, holds significant potential for developing innovative diagnostic tools and therapeutic strategies for OA management.

Overview of the interplay between m6A methylation modification and non-coding RNA and their impact on tumor cells

N6-methyladenosine (m6A) is one of the most common internal modifications in eukaryotic RNA. The presence of m6A on transcripts can affect a series of fundamental cellular processes, including mRNA splicing, nuclear transportation, stability, and translation. The m6A modification is introduced by m6A methyltransferases (writers), removed by demethylases (erasers), and recognized by m6A-binding proteins (readers). Current research has demonstrated that m6A methylation is involved in the regulation of malignant phenotypes in tumors by controlling the expression of cancer-related genes. Non-coding RNAs (ncRNAs) are a diverse group of RNA molecules that do not encode proteins and are widely present in the human genome. This group includes microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and PIWI interaction RNAs (piRNAs). They function as oncogenes or tumor suppressors through various mechanisms, regulating the initiation and progression of cancer. Previous studies on m6A primarily focused on coding RNAs, but recent discoveries have revealed the significant regulatory role of m6A in ncRNAs. Simultaneously, ncRNAs also exert their influence by modulating the stability, splicing, translation, and other biological processes of m6A-related enzymes. The interplay between m6A and ncRNAs collectively contributes to the occurrence and progression of malignant tumors in humans. This review provides an overview of the interactions between m6A regulatory factors and ncRNAs and their impact on tumors.

RNA epigenetics in pulmonary diseases: Insights into methylation modification of lncRNAs in lung cancer

Long non-coding RNAs (lncRNAs) are pivotal controllers of gene expression through epigenetic mechanisms, Methylation, a prominent area of study in epigenetics, significantly impacts cellular processes. Various RNA base methylations, including m6A, m5C, m1A, and 2'-O-methylation, profoundly influence lncRNA folding, interactions, and stability, thereby shaping their functionality. LncRNAs and methylation significantly contribute to tumor development, especially in lung cancer. Their roles encompass cell differentiation, proliferation, the generation of cancer stem cells, and modulation of immune responses. Recent studies have suggested that dysregulation of lncRNA methylation can contribute to lung cancer development. Furthermore, methylation modifications of lncRNAs hold potential for clinical application in lung cancer. Dysregulated lncRNA methylation can promote lung cancer progression and may offer insights into potential biomarker or therapeutic target. This review summarizes the current knowledge of lncRNA methylation in lung cancer and its implications for RNA epigenetics and pulmonary diseases.

Emerging role of RNA modification and long noncoding RNA interaction in cancer

RNA modification, especially N6-methyladenosine, 5-methylcytosine, and N7-methylguanosine methylation, participates in the occurrence and progression of cancer through multiple pathways. The function and expression of these epigenetic regulators have gradually become a hot topic in cancer research. Mutation and regulation of noncoding RNA, especially lncRNA, play a major role in cancer. Generally, lncRNAs exert tumor-suppressive or oncogenic functions and its dysregulation can promote tumor occurrence and metastasis. In this review, we summarize N6-methyladenosine, 5-methylcytosine, and N7-methylguanosine modifications in lncRNAs. Furthermore, we discuss the relationship between epigenetic RNA modification and lncRNA interaction and cancer progression in various cancers. Therefore, this review gives a comprehensive understanding of the mechanisms by which RNA modification affects the progression of various cancers by regulating lncRNAs, which may shed new light on cancer research and provide new insights into cancer therapy.

Association between methyltransferase-like 3 and non-small cell lung cancer: pathogenesis, therapeutic resistance, and clinical applications

Non-small cell lung cancer (NSCLC) is a malignant cancer that with high incidence, recurrence, and mortality rates in human beings, posing significant threats to human health. Moreover, effective early diagnosis of NSCLC remains limited primarily by the lack of accurate biomarkers. Therefore, there is an urgent need to understand the mechanisms underlying NSCLC pathogenesis and treatment failure. Methyltransferase-like 3 (METTL3) is a prototypical member of a family of which its members transfer methyl groups. It has been implicated in modulating the pathogenesis of NSCLC, as well as conferring resistance to NSCLC therapeutics. The targeting of METTL3 for NSCLC treatment has been reported. However, the relationship between METTL3 and NSCLC remains to be demonstrated. In this review, we discuss relevant interrelationships by summarising the studies on METTL3 in NSCLC pathogenesis, therapeutic resistance, and clinical applications. Current research suggests that the upregulation of METTL3 expression propels the tumorigenesis, progression, and treatment resistance of NSCLC. Therefore, we propose that METTL3 is an excellent candidate biomarker for NSCLC diagnosis and prognosis. Therapeutic targeting of METTL3 has significant potential for NSCLC treatment. This review provides a summary of the association between METTL3 and NSCLC, which would be a valuable reference for both basic and clinical research.

Identification of a methyltransferase-related long noncoding RNA signature as a novel prognosis biomarker for lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma (LUAD) accounts for a high proportion of tumor deaths globally, while methyltransferase-related lncRNAs in LUAD were poorly studied.

METHODS

In our study, we focused on two distinct cohorts, TCGA-LUAD and GSE3021, to establish a signature of methyltransferase-related long non-coding RNAs (MeRlncRNAs) in LUAD. We employed univariate Cox and LASSO regression analyses as our main analytical tools. The GSE30219 cohort served as the validation cohort for our findings. Furthermore, to explore the differential pathway enrichments between groups stratified by risk, we utilized Gene Set Enrichment Analysis (GSEA). Additionally, single-sample GSEA (ssGSEA) was conducted to assess the immune infiltration landscape within each sample. Reverse transcription quantitative PCR (RT-qPCR) was also performed to verify the expression of prognostic lncRNAs in both clinically normal and LUAD samples.

RESULTS

In LUAD, we identified a set of 32 MeRlncRNAs. We further narrowed our focus to six prognostic lncRNAs to develop gene signatures. The TCGA-LUAD cohort and GSE30219 were utilized to validate the risk score model derived from these signatures. Our analysis showed that the risk score served as an independent prognostic factor, linked to immune-related pathways. Additionally, the analysis of immune infiltration revealed that the immune landscape in high-risk groups was suppressed, which could contribute to poorer prognoses. We also constructed a regulatory network comprising 6 prognostic lncRNAs, 19 miRNAs, and 21 mRNAs. Confirmatory RT-qPCR results aligned with public database findings, verifying the expression of these prognostic lncRNAs in the samples.

CONCLUSION

The prognostic gene signature of LUAD associated with MeRlncRNAs that we provided, may offer us a comprehensive picture of the prognosis prediction for LUAD patients.

METTL14 regulates CD8+T-cell activation and immune responses to anti-PD-1 therapy in lung cancer

BACKGROUND

N6-methyladenosine (m6A) modification plays an important role in lung cancer. However, methyltransferase-like 14 (METTL14), which serves as the main component of the m6A complex, has been less reported to be involved in the immune microenvironment of lung cancer. This study aimed to analyze the relationship between METTL14 and the immune checkpoint inhibitor programmed death receptor 1 (PD-1) in lung cancer.

METHODS

CCK-8, colony formation, transwell, wound healing, and flow cytometry assays were performed to explore the role of METTL14 in lung cancer progression in vitro. Furthermore, syngeneic model mice were treated with sh-METTL14 andan anti-PD-1 antibody to observe the effect of METTL14 on immunotherapy. Flow cytometry and immunohistochemical (IHC) staining were used to detect CD8 expression. RIP and MeRIP were performed to assess the relationship between METTL14 and HSD17B6. LLC cells and activated mouse PBMCs were cocultured in vitro to mimic immune cell infiltration in the tumor microenvironment. ELISA was used to detect IFN-γ and TNF-α levels.

RESULTS

The online database GEPIA showed that high METTL14 expression indicated a poor prognosis in patients with lung cancer. In vitro assays suggested that METTL14 knockdown suppressed lung cancer progression. In vivo assays revealed that METTL14 knockdown inhibited tumor growth and enhanced the response to PD-1 immunotherapy. Furthermore, METTL14 knockdown enhanced CD8+T-cell activation and infiltration. More importantly, METTL14 knockdown increased the stability of HSD17B6 mRNA by reducing its m6A methylation. In addition, HSD17B6 overexpression promoted the activation of CD8+ T cells.

CONCLUSION

The disruption of METTL14 contributed to CD8+T-cell activation and the immunotherapy response to PD-1 via m6A modification of HSD17B6, thereby suppressing lung cancer progression.

Cancer-derived exosomal lncRNA SNHG3 promotes the metastasis of colorectal cancer through hnRNPC-mediating RNA stability of β-catenin

Metastasis is the leading cause of death in colorectal cancer (CRC) patients. By mediating intercellular communication, exosomes exhibit considerable value in regulating tumor metastasis. Long non-coding RNAs (lncRNAs) are abundant in exosomes and participate in regulating tumor progression. However, it is poorly understood how the cancer-secreted exosomal lncRNAs affect CRC proliferation and metastasis. Here, by analyzing the public databases we identified a lncRNA SNHG3 and demonstrated that SNHG3 was delivered through CRC cells-derived exosomes to promote metastasis in CRC. Mechanistically, exosomal SNHG3 was internalized by CRC cells and afterward upregulated the expression of β-catenin by facilitating the intranuclear transport of hnRNPC. Consequently, the RNA stability of β-catenin was enhanced which led to the activation of EMT and metastasis of CRC cells. Our findings expand the oncogenic mechanisms of exosomal SNHG3 and identify it as a diagnostic marker for CRC.

tiRNA-Val-CAC-2 interacts with FUBP1 to promote pancreatic cancer metastasis by activating c‑MYC transcription

Cumulative studies have established the significance of transfer RNA-derived small RNA (tsRNA) in tumorigenesis and progression. Nevertheless, its function and mechanism in pancreatic cancer metastasis remain largely unclear. Here, we screened and identified tiRNA-Val-CAC-2 as highly expressed in pancreatic cancer metastasis samples by tsRNA sequencing. We also observed elevated levels of tiRNA-Val-CAC-2 in the serum of pancreatic cancer patients who developed metastasis, and patients with high levels of tiRNA-Val-CAC-2 exhibited a worse prognosis. Additionally, knockdown of tiRNA-Val-CAC-2 inhibited the metastasis of pancreatic cancer in vivo and in vitro, while overexpression of tiRNA-Val-CAC-2 promoted the metastasis of pancreatic cancer. Mechanically, we discovered that tiRNA-Val-CAC-2 interacts with FUBP1, leading to enhanced stability of FUBP1 protein and increased FUBP1 enrichment in the c-MYC promoter region, thereby boosting the transcription of c-MYC. Of note, rescue experiments confirmed that tiRNA-Val-CAC-2 could influence pancreatic cancer metastasis via FUBP1-mediated c-MYC transcription. These findings highlight a potential novel mechanism underlying pancreatic cancer metastasis, and suggest that both tiRNA-Val-CAC-2 and FUBP1 could serve as promising prognostic biomarkers and potential therapeutic targets for pancreatic cancer.

m6A methyltransferase METTL14‑mediated RP1‑228H13.5 promotes the occurrence of liver cancer by targeting hsa‑miR‑205/ZIK1

The aim of the present study was to explore the association between N6‑methyladenosine (m6A) modification regulatory gene‑related long noncoding (lnc)RNA RP1‑228H13.5 and cancer prognosis through bioinformatics analysis, as well as the impact of RP1‑228H13.5 on cell biology‑related behaviors and specific molecular mechanisms. Bioinformatics analysis was used to construct a risk model consisting of nine genes. This model can reflect the survival time and differentiation degree of cancer. Subsequently, a competing endogenous RNA network consisting of 3 m6A‑related lncRNAs, six microRNAs (miRs) and 201 mRNAs was constructed. A cell assay confirmed that RP1‑228H13.5 is significantly upregulated in liver cancer cells, which can promote liver cancer cell proliferation, migration and invasion, and inhibit liver cancer cell apoptosis. The specific molecular mechanism may be the regulation of the expression of zinc finger protein interacting with K protein 1 (ZIK1) by targeting the downstream hsa‑miR‑205. Further experiments found that the m6A methyltransferase 14, N6‑adenosine‑methyltransferase subunit mediates the regulation of miR‑205‑5p expression by RP1‑228H13.5. m6A methylation regulatory factor‑related lncRNA has an important role in cancer. The targeting of hsa‑miR‑205 by RP1‑228H13.5 to regulate ZIK1 may serve as a potential mechanism in the occurrence and development of liver cancer.

Exosome-shuttled FTO from BM-MSCs contributes to cancer malignancy and chemoresistance in acute myeloid leukemia by inducing m6A-demethylation: A nano-based investigation

Although bone marrow mesenchymal stem cells (BM-MSCs)-derived exosomes have been reported to be closely associated with acute myeloid leukemia (AML) progression and chemo-resistance, but its detailed functions and molecular mechanisms have not been fully delineated. Besides, serum RNA m6A demethylase fat mass and obesity-associated protein (FTO)-containing exosomes are deemed as important indicators for cancer progression, and this study aimed to investigate the role of BM-MSCs-derived FTO-exosomes in regulating the malignant phenotypes of AML cells. Here, we verified that BM-MSCs-derived exosomes delivered FTO to promote cancer aggressiveness, stem cell properties and Cytosine arabinoside (Ara-C)-chemoresistance in AML cells, and the underlying mechanisms were also uncovered. Our data suggested that BM-MSCs-derived FTO-exo demethylated m6A modifications in the m6A-modified LncRNA GLCC1 to facilitate its combination with the RNA-binding protein Hu antigen R (HuR), which further increased the stability and expression levels of LncRNA GLCC1. In addition, LncRNA GLCC1 was verified as an oncogene to facilitate cell proliferation and enhanced Ara-C-chemoresistance in AML cells. Further experiments confirmed that demethylated LncRNA GLCC1 served as scaffold to facilitate the formation of the IGF2 mRNA binding protein 1 (IGF2BP1)-c-Myc complex, which led to the activation of the downstream tumor-promoting c-Myc-associated signal pathways. Moreover, our rescuing experiments validated that the promoting effects of BM-MSCs-derived FTO-exo on cancer aggressiveness and drug resistance in AML cells were abrogated by silencing LncRNA GLCC1 and c-Myc. Thus, the present firstly investigated the functions and underlying mechanisms by which BM-MSCs-derived FTO-exo enhanced cancer aggressiveness and chemo-resistance in AML by modulating the LncRNA GLCC1-IGF2BP1-c-Myc signal pathway, and our work provided novel biomarkers for the diagnosis, treatment and therapy of AML in clinic.

Non-coding RNA-Mediated N6-Methyladenosine (m6A) deposition: A pivotal regulator of cancer, impacting key signaling pathways in carcinogenesis and therapy response

The emergence of RNA modifications has recently been considered as critical post-transcriptional regulations which governed gene expression. N6-methyladenosine (m6A) modification is the most abundant type of RNA modification which is mediated by three distinct classes of proteins called m6A writers, readers, and erasers. Accumulating evidence has been made in understanding the role of m6A modification of non-coding RNAs (ncRNAs) in cancer. Importantly, aberrant expression of ncRNAs and m6A regulators has been elucidated in various cancers. As the key role of ncRNAs in regulation of cancer hallmarks is well accepted now, it could be accepted that m6A modification of ncRNAs could affect cancer progression. The present review intended to discuss the latest knowledge and importance of m6A epigenetic regulation of ncRNAs including mircoRNAs, long non-coding RNAs, and circular RNAs, and their interaction in the context of cancer. Moreover, the current insight into the underlying mechanisms of therapy resistance and also immune response and escape mediated by m6A regulators and ncRNAs are discussed.

METTL3-mediated m6A modification of lncRNA TSPAN12 promotes metastasis of hepatocellular carcinoma through SENP1-depentent deSUMOylation of EIF3I

In a previous study, we discovered that the level of lnc-TSPAN12 was significantly elevated in hepatocellular carcinoma (HCC) and correlated with a low survival rate. However, the function and mechanism of lnc-TSPAN12 in modulating epithelial-mesenchymal transition (EMT) and metastasis in HCC remains poorly understood. This study demonstrates that lnc-TSPAN12 positively influences migration, invasion, and EMT of HCC cells in vitro and promotes hepatic metastasis in vivo. The modification of N6-methyladenosine, driven by METTL3, is essential for the stability of lnc-TSPAN12, which may partially contribute to the upregulation of lnc-TSPAN12. Mechanistically, lnc-TSPAN12 exhibits direct interactions with EIF3I and SENP1, acting as a scaffold to enhance the SENP1-EIF3I interaction. As a result, the SUMOylation of EIF3I is inhibited, preventing its ubiquitin-mediated degradation. Ultimately, this activates the Wnt/β-catenin signaling pathway, stimulating EMT and metastasis in HCC. Our findings shed light on the regulatory mechanism of lnc-TSPAN12 in HCC metastasis and identify the lnc-TSPAN12-EIF3I/SENP1 axis as a novel therapeutic target for HCC.

Knowledge mapping and current trends of m6A methylation in the field of cancer

Background

Cancer is a serious threat to people's lives and health, killing millions of people every year. Here, we performed a bibliometric analysis of tumor N6-methyladenosine methylation data between 2001 and 2022 to understand research trends and potential future directions.

Methods

A total of 890 papers published in the Web of Science core collection database between January 1, 2001 and December 31, 2022 were analyzed. Bibliometric analysis was performed using VOSviewer software to explore citations, co-authorship, co-citations, and co-occurrence.

Results

Although few papers were published before 2018, there was a rapid increase in publications after 2018. The People's Republic of China published 810 papers with 16,957 citations, both ranking first in the word. Sun Yat Sen University had the highest number of citations and published articles (67 published papers and 2702 citations), indicative of its active collaborative research status. Wang Xiao was the most co-cited author with 546 co-citations. Huang Yufei and Meng Jia ranked first with a link strength of 22, making them the most active collaborative authors. Frontiers in Oncology and Nature were the most active and co-cited journals, with 57 papers and 1953 co-citations, respectively. Studies of tumor N6-methyladenosine methylation can be divided into three categories: "tumor metabolism", "tumor bioinformatics and immunity", and "tumor progression".

Conclusions

This study systematically summarized the research on tumor N6-methyladenosine methylation during the past 20 years and suggested potential ways to explore its biomarkers and immunotherapy in the future.

lncRNA CYTOR promotes lung adenocarcinoma gemcitabine resistance and epithelial-mesenchymal transition by sponging miR-125a-5p and upregulating ANLN and RRM2

Lung adenocarcinoma (LUAD) is one of the most aggressive types of lung cancer. The prognosis of LUAD patients remains poor, and the overall efficacy of gemcitabine-based chemotherapy is still unsatisfactory. Long noncoding RNAs (lncRNAs) play important roles in several cancer types by interacting with multiple proteins, RNA, and DNA. However, the relationship between lncRNA dysregulation and gemcitabine resistance in LUAD has not been fully elucidated. In this study, lncRNA CYTOR expression and its association with the prognosis of LUAD patients are assessed by quantitative RT-PCR and Kaplan-Meier survival analysis. In vitro and in vivo functional studies are conducted to evaluate the biological functions of CYTOR in LUAD. The underlying mechanism regarding the tumor-promoting effects of CYTOR is explored using RNA immunoprecipitation, biotin-labelled RNA pulldown, luciferase reporter assays, and western blot analysis. We identify that CYTOR is an oncogenic lncRNA and is apparently upregulated in LUAD by analysing TCGA-LUAD data. High CYTOR expression is a poor prognostic factor for LUAD. Functional studies reveal that CYTOR confers LUAD cells with stronger resistance to gemcitabine treatment and upregulates the expression levels of epithelial-mesenchymal transition (EMT)-related proteins. Mechanically, CYTOR acts as a competitive endogenous RNA (ceRNA) to absorb miR-125a-5p, weakens the antitumor function of miR-125a-5p, and ultimately upregulates ANLN and RRM2 expressions. Taken together, this study explains the mechanism of lncRNA in the gemcitabine resistance of LUAD and formulates a theoretical framework for the in depth study of LUAD.

METTL3 suppresses invasion of lung cancer via SH3BP5 m6A modification

The metastasis of lung cancer poses a major clinical challenge, and m6A modification has been implicated in regulating the invasive capabilities of tumor cells. However, the mechanisms underlying m6A modification in lung cancer metastasis are not well understood. This study aims to explore the biological functions and molecular mechanisms of methyltransferase-like 3 (METTL3) in lung cancer. In this study, METTL3 were found to be downregulated in lung cancer tissues. Functionally, METTL3 inhibited the migration and invasion abilities of lung cancer cells in vitro. Furthermore, SH3 domain binding protein 5 (SH3BP5) was identified as a downstream target of METTL3. Overexpression of SH3BP5 suppressed the invasive capacity of lung cancer cells, and this regulation was m6A-dependent. Finally, we discovered that YTH N6-methyladenosine RNA binding protein F1 (YTHDF1) mediated stability is responsible for maintaining the m6A modification of SH3BP5 mRNA. Overall, our study provides insights into the critical role of METTL3-mediated m6A modification and m6A-dependent regulatory mechanisms in the progression of human lung cancer. We demonstrated that METTL3 regulates the mRNA stability of SH3BP5 in a YTHDF1-dependent manner, thereby impacting the invasive capacity of lung cancer cells.

N6-methylation in the development, diagnosis, and treatment of gastric cancer

Gastric cancer (GC) ranks third among cancers in terms of mortality rate worldwide. A clear understanding of the mechanisms underlying the genesis and progression of GC will contribute to clinical decision making. N6-methyladenosine (m6A) is the most abundant among diverse mRNA modification types and regulates multiple facets of RNA metabolism. In recent years, emerging studies have shown that m6A modifications are involved in gastric carcinoma tumorigenesis and progression and can potentially be valuable new prospects for diagnosis and prognosis. This article reviews the recent progress regarding m6A in GC.

m6A methylation-mediated regulation of LncRNA MEG3 suppresses ovarian cancer progression through miR-885-5p and the VASH1 pathway

BACKGROUND

Ovarian cancer poses a serious threat to women's health. Due to the difficulty of early detection, most patients are diagnosed with advanced-stage disease or peritoneal metastasis. We found that LncRNA MEG3 is a novel tumor suppressor, but its role in tumor occurrence and development is still unclear.

METHODS

We investigated the expression level of MEG3 in pan-cancer through bioinformatics analysis, especially in gynecological tumors. Function assays were used to detect the effect of MEG3 on the malignant phenotype of ovarian cancer. RIP, RNA pull-down, MeRIP-qPCR, actinomycin D test were carried out to explore the m6A methylation-mediated regulation on MEG3. Luciferase reporter gene assay, PCR and Western blot were implemented to reveal the potential mechanism of MEG3. We further confirmed the influence of MEG3 on tumor growth in vivo by orthotopic xenograft models and IHC assay.

RESULTS

In this study, we discovered that MEG3 was downregulated in various cancers, with the most apparent downregulation in ovarian cancer. MEG3 inhibited the proliferation, migration, and invasion of ovarian cancer cells. Overexpression of MEG3 suppressed the degradation of VASH1 by negatively regulating miR-885-5p, inhibiting the ovarian cancer malignant phenotype. Furthermore, we demonstrated that MEG3 was regulated at the posttranscriptional level. YTHDF2 facilitated MEG3 decay by recognizing METTL3‑mediated m6A modification. Compared with those injected with vector control cells, mice injected with MEG3 knockdown cells showed larger tumor volumes and faster growth rates.

CONCLUSION

We demonstrated that MEG3 is influenced by METTL3/YTHDF2 methylation and restrains ovarian cancer proliferation and metastasis by binding miR-885-5p to increase VASH1 expression. MEG3 is expected to become a therapeutic target for ovarian cancer.

Huaier suppresses cell viability, migration and invasion in human non-small cell lung cancer via lncRNA DLEU2/miR-212-5p/ELF3 axis

Accumulating studies suggest that Huaier exerts anti-tumor effects through intricate mechanisms. Despite extensive research on its efficacy in lung cancer, further investigation is required to elucidate the molecular mechanism of Huaier. The involvement of long noncoding RNAs (lncRNAs) in the anti-lung cancer effects of Huaier remains unknown. In this study, we found Huaier suppressed cell viability, migration and invasion in non-small cell lung cancer (NSCLC) cells. LncRNA sequencing analysis revealed Deleted in lymphocytic leukemia 2 (DLEU2) to be significantly downregulated in Huaier-treated NSCLC cells. Furthermore, DLEU2 silencing was observed to suppress NSCLC progression, while DLEU2 overexpression attenuated the anti-tumor effects of Huaier in NSCLC, thereby promoting cell viability, migration and invasion of NSCLC. The ceRNA role of DLEU2 had been demonstrated in NSCLC, which directly interacted with miR-212-5p to rescue the repression of E74 Like ETS Transcription Factor 3 (ELF3) by this microRNA. Additionally, Huaier was found to regulate the expression of miR-212-5p and ELF3. Functionally, miR-212-5p inhibitor or ELF3 overexpression reversed the effects of DLEU2 silencing or Huaier treatment, resulting in increased colony formation, migration and invasion in NSCLC. Taken together, these results illuminate the mechanism underlying Huaier's anti-tumor effects via the DLEU2/miR-212-5p/ELF3 signaling pathway, which offers novel insights into the anti-tumor effects of Huaier and constitutes a promising therapeutic target for the treatment in NSCLC.

SOX2-OT Binds with ILF3 to Promote Head and Neck Cancer Progression by Modulating Crosstalk between STAT3 and TGF-β Signaling

Long non-coding RNA (lncRNA) is involved in the progression of head and neck squamous cell carcinoma (HNSCC). The molecular mechanism of lncRNA SOX2-OT in HNSCC remains unclear. Therefore, we aimed to elucidate the oncogenic role of SOX2-OT in HNSCC. QRT-PCR analysis was performed in 61 pairs of HNSCC cancer tissues, adjacent normal tissues, and 68 plasma samples confirmed that lncRNA SOX2-OT was overexpressed in cancer tissues and plasma samples, which served as a poor prognostic factor for HNSCC. The FISH assay demonstrated that SOX2-OT was localized in the nucleus and cytoplasm of HNSCC cell lines. Further, the cell function assay confirmed that SOX2-OT promoted cell proliferation and metastasis in vitro and in vivo. RNA pulldown and RIP assay results revealed that SOX2-OT bonds with ILF3 in HNSCC, and the rescue assay confirmed that SOX2-OT played an oncogenic role depending on ILF3 protein expression. Ingenuity pathway analysis and Western blotting indicated that SOX2-OT regulated HNSCC progression by promoting STAT3 phosphorylation and modulating the crosstalk between STAT3 and TGF-β signaling. These results reveal evidence for the role of SOX2-OT in HNSCC progression and metastasis by binding to ILF3, which may serve as a therapeutic target and prognostic biomarker in HNSCC.

Comprehensive landscape and future perspective of long noncoding RNAs in non-small cell lung cancer: it takes a village

Long noncoding RNAs (lncRNAs) are a distinct subtype of RNA that lack protein-coding capacity but exert significant influence on various cellular processes. In non-small cell lung cancer (NSCLC), dysregulated lncRNAs act as either oncogenes or tumor suppressors, contributing to tumorigenesis and tumor progression. LncRNAs directly modulate gene expression, act as competitive endogenous RNAs by interacting with microRNAs or proteins, and associate with RNA binding proteins. Moreover, lncRNAs can reshape the tumor immune microenvironment and influence cellular metabolism, cancer cell stemness, and angiogenesis by engaging various signaling pathways. Notably, lncRNAs have shown great potential as diagnostic or prognostic biomarkers in liquid biopsies and therapeutic strategies for NSCLC. This comprehensive review elucidates the significant roles and diverse mechanisms of lncRNAs in NSCLC. Furthermore, we provide insights into the clinical relevance, current research progress, limitations, innovative research approaches, and future perspectives for targeting lncRNAs in NSCLC. By summarizing the existing knowledge and advancements, we aim to enhance the understanding of the pivotal roles played by lncRNAs in NSCLC and stimulate further research in this field. Ultimately, unraveling the complex network of lncRNA-mediated regulatory mechanisms in NSCLC could potentially lead to the development of novel diagnostic tools and therapeutic strategies.

Lnc AC016727.1/BACH1/HIF-1 α signal loop promotes the progression of non-small cell lung cancer

BACKGROUND

Long noncoding RNAs (lncRNAs) have been reported to play vital roles in the development and progression of cancer. However, their biological significance and functional mechanisms in non-small cell lung cancer (NSCLC) are mostly unclear.

METHODS

We performed RNA-sequencing to predict the differential expression of lncRNAs in clinical NSCLC and paired paracancerous lung tissues. To identify lncRNA expression, quantitative polymerase chain reaction (qPCR) was used. Using both cell and mouse models, We studied lncRNA AC016727.1's function in NSCLC growth and metastasis. Western blot assays, dual luciferase reporter assays, and chromatin immunoprecipitation were used to analyze the functional mechanism of lncRNA AC016727.1.

RESULTS

Our larger NSCLC cohorts validated that the lncRNA AC016727.1 was upregulated in 94 paired NSCLC tissues and correlated with poor survival. Functionally, lncRNA AC016727.1 downregulation inhibited NSCLC cell proliferation, aerobic glycolysis, EMT, and migration, inducing apoptosis. Conversely, upregulated lncRNA AC016727.1 expression exhibited the opposite effect, promoting NSCLC cell survival. Importantly, lncRNA AC016727.1 knockdown inhibited lung cancer growth and slowed the progression of lung metastasis in nude mouse models. Mechanistically, lncRNA AC016727.1 upregulated BACH1 target gene expression by acting as a sponge for miR-98-5p, thereby functioning as a competing endogenous RNA. The function of lncRNA AC016727.1 is mediated by the miR-98-5p/BACH1 axis in NSCLC cells. Meanwhile, the transcription factor HIF-1α can bind to the promoter and activate lncRNA AC016727.1 transcription. lncRNA AC016727.1 regulates HIF-1α expression via BACH1 in NSCLC and forms the lncRNA AC016727.1/BACH1/HIF-1α signaling loop under hypoxic conditions.

CONCLUSION

Our study reveals a novel lncRNA AC016727.1/BACH1/HIF-1α signaling loop in the progression of NSCLC under hypoxic conditions, suggesting that lncRNA AC016727.1 could act as a useful biomarker for NSCLC and a new therapeutic target.

Long noncoding RNA study: Genome-wide approaches

Long noncoding RNAs (lncRNAs) have been confirmed to play a crucial role in various biological processes across several species. Though many efforts have been devoted to the expansion of the lncRNAs landscape, much about lncRNAs is still unknown due to their great complexity. The development of high-throughput technologies and the constantly improved bioinformatic methods have resulted in a rapid expansion of lncRNA research and relevant databases. In this review, we introduced genome-wide research of lncRNAs in three parts: (i) novel lncRNA identification by high-throughput sequencing and computational pipelines; (ii) functional characterization of lncRNAs by expression atlas profiling, genome-scale screening, and the research of cancer-related lncRNAs; (iii) mechanism research by large-scale experimental technologies and computational analysis. Besides, primary experimental methods and bioinformatic pipelines related to these three parts are summarized. This review aimed to provide a comprehensive and systemic overview of lncRNA genome-wide research strategies and indicate a genome-wide lncRNA research system.

Role of m6A modification in regulating the PI3K/AKT signaling pathway in cancer

The phosphoinositide 3-kinase (PI3K)/AKT signaling pathway plays a crucial role in the pathogenesis of cancer. The dysregulation of this pathway has been linked to the development and initiation of various types of cancer. Recently, epigenetic modifications, particularly N6-methyladenosine (m6A), have been recognized as essential contributors to mRNA-related biological processes and translation. The abnormal expression of m6A modification enzymes has been associated with oncogenesis, tumor progression, and drug resistance. Here, we review the role of m6A modification in regulating the PI3K/AKT pathway in cancer and its implications in the development of novel strategies for cancer treatment.

METTL3 facilitates multiple myeloma tumorigenesis by enhancing YY1 stability and pri-microRNA-27 maturation in m6A-dependent manner

Multiple myeloma (MM) is a pernicious plasma cell disorder and has a poor prognosis. N6-methyladenosine (m6A) is an abundant epigenetic RNA modification and is important in cancer progression. Nevertheless, the function of m6A and its regulator METTL3 in MM are rarely reported. Here, we identified the m6A "writers", METTL3, was enhanced in MM and found that Yin Yang 1 (YY1) and primary-miR-27a-3p were the potential target for METTL3. METTL3 promoted primary-miR-27a-3p maturation and YY1 mRNA stability in an m6A manner. YY1 also was found to facilitate miR-27a-3p transcription. METTL3 affected the growth, apoptosis, and stemness of MM cells through accelerating the stability of YY1 mRNA and the maturation of primary-miR-27a-3p in vitro and in vivo. Our results reveal the key function of the METTL3/YY1/miR-27a-3p axis in MM and may provide fresh insights into MM therapy.

LncRNA RP11-58O9.2 predicts poor prognosis and promotes progression of non-small cell lung cancer

OBJECTIVE

Long non-coding RNAs (lncRNAs) play a crucial role in non-small cell lung cancer (NSCLC). This study aimed to investigate the novel biomarker, lncRNA RP11-58O9.2, in patients with NSCLC.

METHODS

RP11-58O9.2 expression in NSCLC cells and tissues was detected by reverse transcription-quantitative polymerase chain reaction. Patient survival was analyzed in relation to RP11-58O9.2 expression levels. RP11-58O9.2 expression was knocked down and endogenous expression was verified in two NSCLC cell lines. Cell proliferation was then assessed by Cell Counting Kit-8 and colony-formation assays, and cell invasion and migration were assessed by Transwell and wound-healing assays, respectively. In vivo experiments were performed in mice, and the combination of RP11-58O9.2 and miR-6749-3p was predicted by miRanda.

RESULTS

RP11-58O9.2 was highly expressed in NSCLC cell lines and tissues, and was associated with advanced stage, lymphatic metastasis, and differentiation group. High RP11-58O9.2 levels were also associated with shorter survival. RP11-58O9.2 knockdown inhibited the proliferation, invasion, and migration of lung cancer cells, and tumor growth in mouse xenografts in vivo. RP11-58O9.2 may target and regulate miR-6749-3p.

CONCLUSIONS

LncRNA RP11-58O9.2 is associated with NSCLC prognosis and promotes lung cancer progression. Further studies are needed to investigate the mechanisms and the regulatory association between RP11-58O9.2 and miR-6749-3p.

RNA splicing alterations in lung cancer pathogenesis and therapy

RNA splicing alterations are widespread and play critical roles in cancer pathogenesis and therapy. Lung cancer is highly heterogeneous and causes the most cancer-related deaths worldwide. Large-scale multi-omics studies have not only characterized the mutational landscapes but also discovered a plethora of transcriptional and post-transcriptional changes in lung cancer. Such resources have greatly facilitated the development of new diagnostic markers and therapeutic options over the past two decades. Intriguingly, altered RNA splicing has emerged as an important molecular feature and therapeutic target of lung cancer. In this review, we provide a brief overview of splicing dysregulation in lung cancer and summarize the recent progress on key splicing events and splicing factors that contribute to lung cancer pathogenesis. Moreover, we describe the general strategies targeting splicing alterations in lung cancer and highlight the potential of combining splicing modulation with currently approved therapies to combat this deadly disease. This review provides new mechanistic and therapeutic insights into splicing dysregulation in cancer.

M6A-mediated-upregulation of lncRNA BLACAT3 promotes bladder cancer angiogenesis and hematogenous metastasis through YBX3 nuclear shuttling and enhancing NCF2 transcription

Lymphatic metastasis is recognized as the leading manner of metastasis in bladder cancer (BLCa), but hematogenous metastasis accounts for a majority of cancer-associated deaths. The past two decades have witnessed tremendous attention in long non-coding RNAs (lncRNAs), which are a new hope for the development of targeted drug therapy for metastatic cancers; however, the underlying mechanism of lncRNAs involved in BLCa hematogenous metastasis remains to be elucidated. Here, we identified BLCa-associated transcript 3 (BLACAT3), a lncRNA, which was aberrantly upregulated in BLCa and corelated with poor prognosis of patients with muscle-invasive bladder cancer. Methodologically, m6A epitranscriptomic microarray, RNA sequencing and mass spectrometry (MS) were used to screen the key molecules of the regulatory axis. Functional assays, animal models and clinical samples were used to explore the roles of BLACAT3 in BLCa in vitro and in vivo. Mechanistically, m6A modification contributes to BLACAT3 upregulation by stabilizing RNA structure. BLACAT3 recruits YBX3 to shuttle into the nucleus, synergistically enhances NCF2 transcription, and promotes BLCa angiogenesis and hematogenous metastasis by activating downstream NF-κB signaling. Our findings will develop prognosis prediction tools for BLCa patients and discover novel therapeutic biological targets for metastatic BLCa.

Construction of lncRNA-m6A gene-mRNA regulatory network to identify m6A-related lncRNAs associated with the progression of lung adenocarcinoma

BACKGROUND

We evaluated the prognostic value of m6A-related long noncoding RNAs (lncRNAs) in lung adenocarcinoma (LUAD).

METHODS

The expression levels of lncRNAs and mRNAs in LUAD and normal adjacent tissues from The Cancer Genome Atlas dataset were analyzed using the limma package. m6A enzyme-related differentially expressed lncRNAs and mRNAs were identified and used to construct a regulatory network. Survival analysis was performed and the correlation between lncRNAs, m6A regulators, and mRNAs was analyzed; followed by functional enrichment analysis.

RESULTS

A comparison of LUAD samples and normal tissues identified numerous differentially expressed lncRNAs and mRNAs, demonstrating that a comprehensive network was established. Two lncRNAs and six mRNAs were selected as prognosis related factors including SH3PXD2A-AS1, MAD2L1, CCNA2, and CDC25C. The pathological stage and recurrence status were identified as independent clinical factors (P < 0.05). The expression levels of these RNAs in the different clinical groups were consistent with those in the different risk groups. The interactions of m6A proteins, two lncRNAs, and six mRNAs were predicted, and functional analysis showed that m6A target mRNAs were involved in the cell cycle, progesterone-mediated oocyte maturation, and oocyte meiosis pathways.

CONCLUSIONS

These m6A target lncRNAs and mRNAs may be promising biomarkers for predicting clinical prognosis, and the lncRNA-m6A regulator-mRNA regulatory network could improve our understanding of m6A modification in LUAD progression.

Crosstalk between m6A and coding/non-coding RNA in cancer and detection methods of m6A modification residues

N6-methyladenosine (m6A) is one of the most common and well-known internal RNA modifications that occur on mRNAs or ncRNAs. It affects various aspects of RNA metabolism, including splicing, stability, translocation, and translation. An abundance of evidence demonstrates that m6A plays a crucial role in various pathological and biological processes, especially in tumorigenesis and tumor progression. In this article, we introduce the potential functions of m6A regulators, including "writers" that install m6A marks, "erasers" that demethylate m6A, and "readers" that determine the fate of m6A-modified targets. We have conducted a review on the molecular functions of m6A, focusing on both coding and noncoding RNAs. Additionally, we have compiled an overview of the effects noncoding RNAs have on m6A regulators and explored the dual roles of m6A in the development and advancement of cancer. Our review also includes a detailed summary of the most advanced databases for m6A, state-of-the-art experimental and sequencing detection methods, and machine learning-based computational predictors for identifying m6A sites.

LncRNA miR663AHG represses the development of colon cancer in a miR663a-dependent manner

The MIR663AHG gene encodes both miR663AHG and miR663a. While miR663a contributes to the defense of host cells against inflammation and inhibits colon cancer development, the biological function of lncRNA miR663AHG has not been previously reported. In this study, the subcellular localization of lncRNA miR663AHG was determined by RNA-FISH. miR663AHG and miR663a were measured by qRT-PCR. The effects of miR663AHG on the growth and metastasis of colon cancer cells were investigated in vitro and in vivo. CRISPR/Cas9, RNA pulldown, and other biological assays were used to explore the underlying mechanism of miR663AHG. We found that miR663AHG was mainly distributed in the nucleus of Caco2 and HCT116 cells and the cytoplasm of SW480 cells. The expression level of miR663AHG was positively correlated with the level of miR663a (r = 0.179, P = 0.015) and significantly downregulated in colon cancer tissues relative to paired normal tissues from 119 patients (P < 0.008). Colon cancers with low miR663AHG expression were associated with advanced pTNM stage (P = 0.021), lymph metastasis (P = 0.041), and shorter overall survival (hazard ratio = 2.026; P = 0.021). Experimentally, miR663AHG inhibited colon cancer cell proliferation, migration, and invasion. The growth of xenografts from RKO cells overexpressing miR663AHG was slower than that of xenografts from vector control cells in BALB/c nude mice (P = 0.007). Interestingly, either RNA-interfering or resveratrol-inducing expression changes of miR663AHG or miR663a can trigger negative feedback regulation of transcription of the MIR663AHG gene. Mechanistically, miR663AHG could bind to miR663a and its precursor pre-miR663a, and prevent the degradation of miR663a target mRNAs. Disruption of the negative feedback by knockout of the MIR663AHG promoter, exon-1, and pri-miR663A-coding sequence entirely blocked these effects of miR663AHG, which was restored in cells transfected with miR663a expression vector in rescue experiment. In conclusion, miR663AHG functions as a tumor suppressor that inhibits the development of colon cancer through its cis-binding to miR663a/pre-miR663a. The cross talk between miR663AHG and miR663a expression may play dominant roles in maintaining the functions of miR663AHG in colon cancer development.

The critical roles of m6A RNA methylation in lung cancer: from mechanism to prognosis and therapy

Lung cancer, a highly malignant disease, greatly affects patients' quality of life. N6-methyladenosine (m6A) is one of the most common posttranscriptional modifications of various RNAs, including mRNAs and ncRNAs. Emerging studies have demonstrated that m6A participates in normal physiological processes and that its dysregulation is involved in many diseases, especially pulmonary tumorigenesis and progression. Among these, regulators including m6A writers, readers and erasers mediate m6A modification of lung cancer-related molecular RNAs to regulate their expression. Furthermore, the imbalance of this regulatory effect adversely affects signalling pathways related to lung cancer cell proliferation, invasion, metastasis and other biological behaviours. Based on the close association between m6A and lung cancer, various prognostic risk models have been established and novel drugs have been developed. Overall, this review comprehensively elaborates the mechanism of m6A regulation in the development of lung cancer, suggesting its potential for clinical application in the therapy and prognostic assessment of lung cancer.

Novel insights into mutual regulation between N6-methyladenosine modification and LncRNAs in tumors

N⁶-methyladenosine (m⁶A), one of the most common RNA methylation modifications, has emerged in recent years as a new layer of the regulatory mechanism controlling gene expression in eukaryotes. As a reversible epigenetic modification, m⁶A not only occurs on mRNAs but also on Long non-coding RNAs (LncRNAs). As we all known, despite LncRNAs cannot encode proteins, they affect the expression of proteins by interacting with mRNAs or miRNAs, thus playing important roles in the occurrence and development of a variety of tumors. Up to now, it has been widely accepted that m⁶A modification on LncRNAs affects the fate of the corresponding LncRNAs. Interestingly, levels and functions of m⁶A modifications are also mediated by LncRNAs through affecting the m⁶A methyltransferases (METTL3, METTL14, WTAP, METTL16, etc.), demethylases (FTO, ALKBH5) and methyl-binding proteins (YTHDFs, YTHDCs, IGF2BPs, HNRNPs, etc.), which are collectively referred to as "m⁶A regulators". In this review, we summarized the mutual regulation mechanisms between N⁶-methyladenosine modification and LncRNAs in cancer progression, metastasis, invasion and drug resistance. In detail, we focus on the specific mechanisms of m⁶A modification, which is mediated by methyltransferases and demethylases, involves in the regulation of LncRNA levels and functions in the first part. And section two intensively displays the mediation roles of LncRNAs in m⁶A modification via changing the regulatory proteins. At last part, we described the interaction effects between LncRNAs and methyl-binding proteins of m⁶A modification during various tumor occurrence and development.

m6A-mediated upregulation of LINC01003 regulates cell migration by targeting the CAV1/FAK signaling pathway in glioma

BACKGROUND

Long non-coding RNAs (lncRNAs) play important roles in the progression of glioma. Here, we examined the potential functions of a lncRNA, LINC01003, in glioma and characterized the underlying molecular mechanisms.

METHODS

The GEIPA2 and Chinese Glioma Genome Atlas (CCGA) databases were employed to analyze gene expression and the overall survival curve in patients with glioma. The functions of LINC01003 in glioma growth and migration were assessed by loss-of-function experiments in vitro and in vivo. RNA sequencing was used to determine the signaling pathways effected by LINC01003. Bioinformatics analysis and RNA immunoprecipitation (RIP) assays were used to explore the mechanism underlying the N6-methyladenine (m⁶A) modification-dependent upregulation of LINC01003 in glioma.

RESULTS

LINC01003 expression was upregulated in glioma cell lines and tissues. Higher LINC01003 expression predicted shorter overall survival time in glioma patients. Functionally, LINC01003 knockdown inhibited the cell cycle and cell proliferation and migration in glioma cells. Mechanistically, RNA sequencing revealed that LINC01003 mediated the focal adhesion signaling pathway. Furthermore, LINC01003 upregulation is induced by m⁶A modification regulated by METTL3.

CONCLUSION

This study characterized LINC01003 as a lncRNA that contributes to tumorigenesis in glioma and demonstrated that the LINC01003-CAV1-FAK axis serves as a potential therapeutic target for glioma.

Far upstream element-binding protein 1 confers lobaplatin resistance by transcriptionally activating PTGES and facilitating the arachidonic acid metabolic pathway in osteosarcoma

Drug resistance is a major obstacle in cancer treatment and recurrence prevention and leads to poor outcomes in patients suffering from osteosarcoma. Clarification of the mechanism of drug resistance and exploration of effective strategies to overcome this obstacle could lead to clinical benefits for these patients. The expression of far upstream element-binding protein 1 (FUBP1) was found to be markedly elevated in osteosarcoma cell lines and clinical specimens compared with osteoblast cells and normal bone specimens. High expression of FUBP1 was correlated with a more aggressive phenotype and a poor prognosis in osteosarcoma patients. We found that overexpression of FUBP1 confers lobaplatin resistance, whereas the inhibition of FUBP1 sensitizes osteosarcoma cells to lobaplatin-induced cytotoxicity both in vivo and in vitro. Chromatin immunoprecipitation-seq and RNA-seq were performed to explore the potential mechanism. It was revealed that FUBP1 could regulate the transcription of prostaglandin E synthase (PTGES) and subsequently activate the arachidonic acid (AA) metabolic pathway, which leads to resistance to lobaplatin. Our investigation provides evidence that FUBP1 is a potential therapeutic target for osteosarcoma patients. Targeting FUBP1, its downstream target PTGES and the AA metabolic pathway may be promising strategies for sensitizing chemoresistant osteosarcoma cells to lobaplatin.

Regulatory network and targeted interventions for CCDC family in tumor pathogenesis

CCDC (coiled-coil domain-containing) is a coiled helix domain that exists in natural proteins. There are about 180 CCDC family genes, encoding proteins that are involved in intercellular transmembrane signal transduction and genetic signal transcription, among other functions. Alterations in expression, mutation, and DNA promoter methylation of CCDC family genes have been shown to be associated with the pathogenesis of many diseases, including primary ciliary dyskinesia, infertility, and tumors. In recent studies, CCDC family genes have been found to be involved in regulation of growth, invasion, metastasis, chemosensitivity, and other biological behaviors of malignant tumor cells in various cancer types, including nasopharyngeal carcinoma, lung cancer, colorectal cancer, and thyroid cancer. In this review, we summarize the involvement of CCDC family genes in tumor pathogenesis and the relevant upstream and downstream molecular mechanisms. In addition, we summarize the potential of CCDC family genes as tumor therapy targets. The findings discussed here help us to further understand the role and the therapeutic applications of CCDC family genes in tumors.

Oncogenic roles and related mechanisms of the long non-coding RNA MINCR in human cancers

Long non-coding RNAs (lncRNAs) play vital roles in regulating epigenetic mechanisms and gene expression levels, and their dysregulation is closely associated with a variety of diseases such as cancer. Several studies have demonstrated that lncRNAs are dysregulated during tumor progression. Recently, the MYC-induced long non-coding RNA MINCR, a newly identified lncRNA, has been demonstrated to act as an oncogene in different cancers, including gallbladder cancer, hepatocellular cancer, colorectal cancer, non-small cell lung cancer, oral squamous cell carcinoma, nasopharyngeal cancer, and glioma. Moreover, MINCR has been reported to act as a biomarker in the prognosis of patients with different cancers. In this review, we summarize and analyze the oncogenic roles of MINCR in a variety of human cancers in terms of its clinical significance, biological functions, cellular activities, and regulatory mechanism. Our analysis of the literature suggests that MINCR has potential as a novel biomarker and therapeutic target in human cancers.

Construction of an m6A-related lncRNA model for predicting prognosis and immunotherapy in patients with lung adenocarcinoma

N6-methyladenosine (m6A)-related lncRNAs could be involved in the development of multiple tumors with an unknown role in lung adenocarcinoma (LUAD). Hence, gene expression data and clinical data of LUAD patients were acquired from The Cancer Genome Atlas Database. The prognostic m6A-related lncRNAs were identified through differential lncRNA expression analysis and Spearman's correlation analysis. The least absolute shrinkage and selection operator regression was used to establish the prognostic risk model, so as to evaluate and validate the predictive performance with survival analysis and receiver operating characteristic curve analysis. The expression of immune checkpoints, immune cell infiltration and drug sensitivity of patients in different risk groups were analyzed separately. A total of 19 prognostic m6A-related lncRNAs were identified to set up the prognostic risk model. The patients were divided into high- and low-risk groups based on the median value of the risk scores. Compared with the patients in the low-risk group, the prognosis of the patients in the high-risk group was relatively worse. The receiver operating characteristic curves indicated that this model had excellent sensitivity and specificity. Multivariate Cox regression analysis demonstrated that the risk score could be supposed as an independent prognostic risk factor. We highlighted that the risk scores were correlated with immune cell infiltration and drug sensitivity for constructing a prognostic risk model in LUAD patients based on m6A-related lncRNAs.

Long noncoding RNA SNHG15: A promising target in human cancers

As oncogenes or tumor suppressor genes, lncRNAs played an important role in tumorigenesis and the progression of human cancers. The lncRNA SNHG15 has recently been revealed to be dysregulated in malignant tumors, suggesting the aberrant expression of which contributes to clinical features and regulates various oncogenic processes. We have selected extensive literature focused on SNHG15 from electronic databases, including studies relevant to its clinical significance and the critical events in cancer-related processes such as cell proliferation, apoptosis, autophagy, metastasis, and drug resistance. This review summarized the current understanding of SNHG15 in cancer, mainly focusing on the pathological features, known biological functions, and underlying molecular mechanisms. Furthermore, SNHG15 has been well-documented to be an effective diagnostic and prognostic marker for tumors, offering novel therapeutic interventions in specific subsets of cancer cells.

METTL3 activates PERK-eIF2α dependent coelomocyte apoptosis by targeting the endoplasmic reticulum degradation-related protein SEL1L in echinoderms

N6-methyladenosine (m6A) plays an important role in regulating many physiological and disease processes in vertebrates, in which methyltransferase-like 3 (METTL3) is the best-known m6A methyltransferase. However, the functional roles of invertebrate METTL3 have not yet been highlighted. In this study, we found that METTL3 from Apostichopus japonicus (AjMETTL3) was significantly induced in coelomocytes accompanied by higher levels of m6A modification in response to Vibrio splendidus challenge. Overexpression or silencing of AjMETTL3 in coelomocytes increased or decreased the m6A levels and promoted or inhibited V. splendidus-induced coelomocyte apoptosis, respectively. To further explore the molecular mechanism of AjMETTL3-mediated coelomic immunity, m6A-seq analysis revealed that the endoplasmic reticulum-related degradation (ERAD) pathway was significantly enriched, in which suppressor/enhancer of Lin-12-like (AjSEL1L) was suggested to be a target of AjMETTL3 in a negative regulatory manner. Functional analysis revealed that the increased AjMETTL3 reduced the stability of AjSEL1L mRNA by targeting the m6A modification site of 2004 bp-GGACA-2008 bp. The decreased AjSEL1L was further confirmed to be involved in AjMETTL3-mediated coelomocyte apoptosis. Mechanistically, the inhibited AjSEL1L increased the transcription of AjOS9 and Ajp97 in the EARD pathway to promote ubiquitin protein accumulation and ER stress, which further activated AjPERK-AjeIF2α pathway dependent coelomocyte apoptosis, but not the AjIRE1 or AjATF6 pathway. Taken together, our results supported invertebrate METTL3-mediated coelomocyte apoptosis by regulating the PERK-eIF2α pathway.

The role of selected non-coding RNAs in the biology of non-small cell lung cancer

Lung cancer is the second most frequently diagnosed cancer worldwide and a leading cause of cancer-related deaths. Non-small cell lung carcinoma (NSCLC) represents 85% of all cases. Accumulating evidence highlights the outstanding role of non-coding RNA (ncRNA) in regulating the tumorigenesis process by modulating crucial signaling pathways. Micro RNA (miRNA), long non-coding RNA (lncRNA) and circular RNA (circRNA) are either up- or downregulated in lung cancer patients and can promote or suppress the progression of the disease. These molecules interact with messenger RNA (mRNA) and with each other to regulate gene expression and stimulate proto-oncogenes or silence tumor suppressors. NcRNAs provide a new strategy to diagnose or treat lung cancer patients and multiple molecules have already been identified as potential biomarkers or therapeutic targets. The aim of this review is to summarize the current evidence on the roles of miRNA, lncRNA and circRNA in NSCLC biology and present their clinical potential.

The effects of epigenetic modifications on bone remodeling in age-related osteoporosis

PURPOSE

As the population ages, there is an increased risk of fracture and morbidity diseases associated with aging, such as age-related osteoporosis and other bone diseases linked to aging skeletons.

RESULTS

Several bone-related cells, including multipotent bone mesenchymal stem cells, osteoblasts that form bone tissue, and osteoclasts that break it down, are in symbiotic relationships throughout life. Growing evidence indicates that epigenetic modifications of cells caused by aging contribute to compromised bone remodeling and lead to osteoporosis. A number of epigenetic mechanisms are at play, including DNA/RNA modifications, histone modifications, microRNAs (miRNAs), and long noncoding RNAs (lncRNAs), as well as chromatin remodeling.

CONCLUSION

In this review, we summarized the epigenetic modifications of different bone-related cells during the development and progression of osteoporosis associated with aging. Additionally, we described a compensatory recovery mechanism under epigenetic regulation that may lead to new strategies for regulating bone remodeling in age-related osteoporosis.

The roles of N6-methyladenosine and its target regulatory noncoding RNAs in tumors: classification, mechanisms, and potential therapeutic implications

N6-methyladenosine (m6A) is one of the epigenetic modifications of RNA. The addition of this chemical mark to RNA molecules regulates gene expression by affecting the fate of the RNA molecules. This posttranscriptional RNA modification is reversible and regulated by methyltransferase "writers" and demethylase "erasers". The fate of m6A-modified RNAs depends on the function of different "readers" that recognize and bind to them. Research on m6A methylation modification has recently increased due to its important role in regulating cancer progression. Noncoding RNAs (ncRNAs) are a class of RNA molecules that are transcribed from the genome but whose roles have been overlooked due to their lack of well-defined potential for translation into proteins or peptides. However, this misconception has now been completely overturned. ncRNAs regulate various diseases, especially tumors, and it has been confirmed that they play either tumor-promoting or tumor-suppressing roles in almost all types of tumors. In this review, we discuss the m6A modification of different types of ncRNA and summarize the mechanisms involved. Finally, we discuss the progress of research on clinical treatment and discuss the important significance of the m6A modification of ncRNAs in the clinical treatment of tumors.

A novel cuproptosis-related lncRNA signature to predict prognosis and immune landscape of lung adenocarcinoma

Background

Cuproptosis, a recently discovered type of programmed cell death (PCD), paves a new avenue for cancer treatment. It has been revealed that PCD-related lncRNAs play a critical role in various biological processes of lung adenocarcinoma (LUAD). However, the role of cuproptosis-related lncRNA (CuRLs) remains unclear. This study aimed to identify and validate a CuRLs-based signature for the prognostic prediction of patients with LUAD.

Methods

RNA sequencing data and clinical information of LUAD were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Pearson correlation analysis was used to identify CuRLs. Univariate Cox regression analysis, Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression, and stepwise multivariate Cox analysis were applied to construct a novel prognostic CuRLs signature. A nomogram was developed for the prediction of patient survival outcomes. Gene set variation analysis (GSVA), gene set enrichment analysis (GSEA), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were utilized to explore potential functions underlying the CuRLs signature. Patients were divided into low- and high-risk groups. Several algorithms, such as tumor immune estimation resource (TIMER), cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT), and QuanTIseq, were combined to comprehensively investigate the differences in immune landscape between different risk groups. Sensitivity to common anticancer drugs was analyzed using the pRRophetic algorithm.

Results

We constructed a novel prognostic signature based on 10 CuRLs, including CARD8-AS1, RUNDC3A-AS1, TMPO-AS1, MIR31HG, SEPSECS-AS1, DLGAP1-AS1, LINC01137, ZSCAN16-AS1, APTR, and ELOA-AS1. This 10-CuRLs risk signature showed great diagnostic accuracy combined with traditional clinical risk factors, and a nomogram was constructed for potential clinical translation. The tumor immune microenvironment was significantly different between different risk groups. Among drugs commonly used in the treatment of lung cancer, the sensitivity of cisplatin, docetaxel, gemcitabine, gefitinib, and paclitaxel was higher in low-risk patients, and patients in the low-risk group may benefit more from imatinib.

Conclusions

These results revealed the outstanding contribution of the CuRLs signature to the evaluation of prognosis and treatment modalities for patients with LUAD. The differences in characteristics between different risk groups provide an opportunity for better patient stratification and to explore novel drugs in different risk groups.