bims-rimeca 2023-11-26 papers

bims-rimeca

Biomed News

on RNA methylation in cancer

Issue of 2023‒11‒26
seventeen papers selected by
Sk Ramiz Islam, Saha Institute of Nuclear Physics

METTL3 promotes colorectal cancer progression through activating JAK1/STAT3 signaling pathway.
Identification and verification of m6A-related miRNAs correlated with prognosis and immune microenvironment in colorectal cancer.
Identifying N6-Methyladenosine Sites in HepG2 Cell Lines Using Oxford Nanopore Technology.
IGF2BP2 Drives Cell Cycle Progression in Triple-Negative Breast Cancer by Recruiting EIF4A1 to Promote the m6A-Modified CDK6 Translation Initiation Process.
EGFR promotes ALKBH5 nuclear retention to attenuate N6-methyladenosine and protect against ferroptosis in glioblastoma.
M6A Demethylase Inhibits Osteogenesis of Dental Follicle Stem Cells via Regulating miR-7974/FKBP15 Pathway.
Methylation-Powered Assembly of a Single Quantum Dot-Based FRET Nanosensor for Antibody-Free and Enzyme-Free Monitoring of Locus-Specific N6-Methyladenosine in Clinical Tissues.
AGAP2-AS1 promotes the assembly of m6A methyltransferases and activation of the IL6/STAT3 pathway by binding with WTAP in the carcinogenesis of gastric cancer.
Discovery of Pyrazolo[1,5-a]pyrimidine Derivative as a Novel and Selective ALKBH5 Inhibitor for the Treatment of AML.
ALKBH5 regulates N(6)-methyladenosine (m6A) methylation of MG53 to attenuate myocardial infarction by inhibiting apoptosis and oxidative stress.
Identification of m6A Modification Regulated by Dysregulated circRNAs in Decidua of Recurrent Pregnancy Loss.
m6A modified BACE1-AS contributes to liver metastasis and stemness-like properties in colorectal cancer through TUFT1 dependent activation of Wnt signaling.
FTO-mediated ZNF687 accelerates tumor growth, metastasis, and angiogenesis in colorectal cancer through the Wnt/β-catenin pathway.
ALKBH5 Stabilized N6-Methyladenosine-Modified LOC4191 to Suppress E. coli-Induced Apoptosis.
SUMOylation-driven mRNA circularization enhances translation and promotes lymphatic metastasis of bladder cancer.
METTL3 regulates the proliferation, metastasis and EMT progression of bladder cancer through P3H4.
Effects of Methionine Restriction from Different Sources on Sperm Quality in Aging Mice.

Cell Death Dis. 2023 Nov 25. 14(11): 765

METTL3 promotes colorectal cancer progression through activating JAK1/STAT3 signaling pathway.

Yuechao Sun, Weipeng Gong, Song Zhang.

The role of METTL3-mediated N6-methyladenosine (m6A) modification has been elucidated in several cancers, but the concrete mechanism underlying its function in colorectal cancer is still obscure. Here, we revealed that upregulated methyltransferase-like 3 (METTL3) in colorectal cancer exerted both methyltransferase activity-dependent and -independent functions in gene regulation. METTL3 deposited m6A on the 3' untranslated region of the JAK1 transcript to promote JAK1 translation relying on YTHDF1 recognition. Besides, METTL3 was redistributed to the STAT3 promoter and worked in concert with NF-κB to facilitate STAT3 transcription, which was achieved independently on METTL3 methyltransferase activity. The increased JAK1 and STAT3 corporately contributed to the activation of the p-STAT3 signaling pathway and further upregulated downstream effectors expressions, including VEGFA and CCND1, which finally resulted in enhanced cancer cell proliferation and metastasis in vitro and in vivo. Collectively, our study revealed the unappreciated dual role of METTL3 as an m6A writer and a transcription regulator, which worked together in the same signaling pathway to drive colorectal cancer malignancy.

DOI: https://doi.org/10.1038/s41419-023-06287-w
Medicine (Baltimore). 2023 Nov 17. 102(46): e35984

Identification and verification of m6A-related miRNAs correlated with prognosis and immune microenvironment in colorectal cancer.

Xinze Qiu, Da Chen, Shanpei Huang, Ni Chen, Jiangni Wu, Shengmei Liang, Peng Peng, Mengbin Qin, Jiean Huang, Shiquan Liu.

It's well known that N6-methyladenosine (m6A) modification is the most abundant modification in multiple RNA species. miRNAs play important roles in m6A modification and are closely related with occurrence and development of colorectal cancer (CRC). Thus, the aim of this study was to identify the prognostic value of m6A-related miRNAs and explore the correlation between the miRNAs and immune microenvironment in CRC. The differentially expressed m6A regulators and differentially expressed miRNAs between CRC tissues and adjacent normal tissues were identified based on TCGA dataset, and the m6A-related miRNAs were screened. The CRC patients from TCGA were randomized (1:1) into training set and validation set, and the risk score was established in the training set. Next, risk score was verified in the validation set and GSE92928 from GEO datasets. Besides, the relationship among tumor mutational burden, immune microenvironment and risk score were analyzed. What's more, RT-qPCR were used to explore the expression levels of the miRNAs in risk score between SW480 and SW620. A total of 29 m6A-related miRNAs were screened out, and a 5-differentially expressed miRNAs risk score was established. Kaplan-Meier analysis and ROC curves revealed the risk score could predict the prognosis of CRC, accurately. Similarly, the patients in the high-risk group had shorter overall survival in GSE92928. The risk score was relevant with the tumor mutational burden and immune infiltration, and the expression of HAVCR2 was significant difference between 2 risk groups. The expression levels of miR-328-3p, miR-3934-5p, miR-664b-5p and miR-3677-3p were down-regulated in SW620 compared with SW480, only the expression level of miR-200c-5p was up-regulated in SW620. The findings provided the new insights into the correlation between miRNAs and m6A regulators. The m6A-related miRNAs could predict the prognosis of CRC and provide the valuable information of immunotherapy in CRC patients.

DOI: https://doi.org/10.1097/MD.0000000000035984
Int J Mol Sci. 2023 Nov 18. pii: 16477. [Epub ahead of print]24(22):

Identifying N6-Methyladenosine Sites in HepG2 Cell Lines Using Oxford Nanopore Technology.

Viktoriia A Arzumanian, Ilya Y Kurbatov, Konstantin G Ptitsyn, Svetlana A Khmeleva, Leonid K Kurbatov, Sergey P Radko, Ekaterina V Poverennaya.

  RNA modifications, particularly N6-methyladenosine (m6A), are pivotal regulators of RNA functionality and cellular processes. We analyzed m6A modifications by employing Oxford Nanopore technology and the m6Anet algorithm, focusing on the HepG2 cell line. We identified 3968 potential m6A modification sites in 2851 transcripts, corresponding to 1396 genes. A gene functional analysis revealed the active involvement of m6A-modified genes in ubiquitination, transcription regulation, and protein folding processes, aligning with the known role of m6A modifications in histone ubiquitination in cancer. To ensure data robustness, we assessed reproducibility across technical replicates. This study underscores the importance of evaluating algorithmic reproducibility, especially in supervised learning. Furthermore, we examined correlations between transcriptomic, translatomic, and proteomic levels. A strong transcriptomic-translatomic correlation was observed. In conclusion, our study deepens our understanding of m6A modifications' multifaceted impacts on cellular processes and underscores the importance of addressing reproducibility concerns in analytical approaches.

Keywords:  HepG2; N6-methyladenosine; epitranscriptome; mRNA modifications

DOI:  https://doi.org/10.3390/ijms242216477
Adv Sci (Weinh). 2023 Nov 20. e2305142

IGF2BP2 Drives Cell Cycle Progression in Triple-Negative Breast Cancer by Recruiting EIF4A1 to Promote the m6A-Modified CDK6 Translation Initiation Process.

Tian Xia, Xin-Yuan Dai, Ming-Yi Sang, Xu Zhang, Feng Xu, Jing Wu, Liang Shi, Ji-Fu Wei, Qiang Ding.

  IGF2BP2 is a new identified N6-methyladenosine (m6A) reader and associated with poor prognosis in many tumors. However, its role and related mechanism in breast cancer, especially in triple-negative breast cancer (TNBC), remains unclear. In this study, it is found that IGF2BP2 is highly expressed in TNBC due to the lower methylation level in its promoter region. Functional and mechanical studies displayed that IGF2BP2 could promote TNBC proliferation and the G1/S phase transition of the cell cycle via directly regulating CDK6 in an m6A-dependent manner. Surprising, the regulation of protein levels of CDK6 by IGF2BP2 is related to the changes in translation rate during translation initiation, rather than mRNA stability. Moreover, EIF4A1 is found to be recruited by IGF2BP2 to promote the translation output of CDK6, providing new evidence for a regulatory role of IGF2BP2 between m6A methylation and translation. Downregulation of IGF2BP2 in TNBC cell could enhance the sensitivity to abemaciclib, a CDK4/6 inhibitor. To sum up, our study revealed IGF2BP2 could facilitate the translation output of CDK6 via recruiting EIF4A1 and also provided a potential therapeutic target for the diagnosis and treatment of TNBC, as well as a new strategy for broadening the drug indications for CDK4/6 inhibitors.

Keywords:  CDK6; Cell cycle; IGF2BP2; N6-methyladenosine (m6A)

DOI:  https://doi.org/10.1002/advs.202305142
Mol Cell. 2023 Nov 08. pii: S1097-2765(23)00862-6. [Epub ahead of print]

EGFR promotes ALKBH5 nuclear retention to attenuate N6-methyladenosine and protect against ferroptosis in glioblastoma.

Deguan Lv, Cuiqing Zhong, Deobrat Dixit, Kailin Yang, Qiulian Wu, Bhaskar Godugu, Briana C Prager, Guofeng Zhao, Xiuxing Wang, Qi Xie, Shideng Bao, Chuan He, Dieter Henrik Heiland, Michael G Rosenfeld, Jeremy N Rich.

  Growth factor receptors rank among the most important oncogenic pathways, but pharmacologic inhibitors often demonstrate limited benefit as monotherapy. Here, we show that epidermal growth factor receptor (EGFR) signaling repressed N6-methyladenosine (m6A) levels in glioblastoma stem cells (GSCs), whereas genetic or pharmacologic EGFR targeting elevated m6A levels. Activated EGFR induced non-receptor tyrosine kinase SRC to phosphorylate the m6A demethylase, AlkB homolog 5 (ALKBH5), thereby inhibiting chromosomal maintenance 1 (CRM1)-mediated nuclear export of ALKBH5 to permit sustained mRNA m6A demethylation in the nucleus. ALKBH5 critically regulated ferroptosis through m6A modulation and YTH N6-methyladenosine RNA binding protein (YTHDF2)-mediated decay of the glutamate-cysteine ligase modifier subunit (GCLM). Pharmacologic targeting of ALKBH5 augmented the anti-tumor efficacy of EGFR and GCLM inhibitors, supporting an EGFR-ALKBH5-GCLM oncogenic axis. Collectively, EGFR reprograms the epitranscriptomic landscape through nuclear retention of the ALKBH5 demethylase to protect against ferroptosis, offering therapeutic paradigms for the treatment of lethal cancers.

Keywords:  ALKBH5; EGFR; GCLM; SRC; YTHDF2; cancer stem cell; ferroptosis; glioblastoma; glioblastoma stem cell; m(6)A

DOI:  https://doi.org/10.1016/j.molcel.2023.10.025
Int J Mol Sci. 2023 Nov 09. pii: 16121. [Epub ahead of print]24(22):

M6A Demethylase Inhibits Osteogenesis of Dental Follicle Stem Cells via Regulating miR-7974/FKBP15 Pathway.

Linwei Zheng, Zhizheng Li, Bing Wang, Rui Sun, Yuqi Sun, Jiangang Ren, Jihong Zhao.

  N6-methyladenosine (m6A) is the most abundant RNA modification, regulating gene expression in physiological processes. However, its effect on the osteogenic differentiation of dental follicle stem cells (DFSCs) remains unknown. Here, m6A demethylases, the fat mass and obesity-associated protein (FTO), and alkB homolog 5 (ALKBH5) were overexpressed in DFSCs, followed by osteogenesis assay and transcriptome sequencing to explore potential mechanisms. The overexpression of FTO or ALKBH5 inhibited the osteogenesis of DFSCs, evidenced by the fact that RUNX2 independently decreased calcium deposition and by the downregulation of the osteogenic genes OCN and OPN. MiRNA profiling revealed that miR-7974 was the top differentially regulated gene, and the overexpression of m6A demethylases significantly accelerated miR-7974 degradation in DFSCs. The miR-7974 inhibitor decreased the osteogenesis of DFSCs, and its mimic attenuated the inhibitory effects of FTO overexpression. Bioinformatic prediction and RNA sequencing analysis suggested that FK506-binding protein 15 (FKBP15) was the most likely target downstream of miR-7974. The overexpression of FKBP15 significantly inhibited the osteogenesis of DFSCs via the restriction of actin cytoskeleton organization. This study provided a data resource of differentially expressed miRNA and mRNA after the overexpression of m6A demethylases in DFSCs. We unmasked the RUNX2-independent effects of m6A demethylase, miR-7974, and FKBP15 on the osteogenesis of DFSCs. Moreover, the FTO/miR-7974/FKBP15 axis and its effects on actin cytoskeleton organization were identified in DFSCs.

Keywords:  FK506-binding protein; N6-methyladenosine; actin cytoskeleton; dental follicle stem cell; microRNA; osteogenesis

DOI:  https://doi.org/10.3390/ijms242216121
Anal Chem. 2023 Nov 24.

Methylation-Powered Assembly of a Single Quantum Dot-Based FRET Nanosensor for Antibody-Free and Enzyme-Free Monitoring of Locus-Specific N6-Methyladenosine in Clinical Tissues.

Jinping Hu, Ya-Ting Zhang, Yun Han, Fei Ma, Chen-Zhong Li, Lin Cui, Chun-Yang Zhang.

N6-Methyladenosine (m6A) is the most pervasive and evolutionarily conserved epitranscriptomic modification in long noncoding RNA (lncRNA), and its dysregulation may induce aberrant transcription and translation programs. Herein, we demonstrate the methylation-powered assembly of a single quantum dot (QD)-based fluorescence resonance energy transfer (FRET) nanosensor for antibody- and enzyme-free monitoring of locus-specific m6A in clinical tissues. The m6A-sensitive DNAzyme VMC10 is employed to identify a specific m6A site in lncRNA, and it catalyzes the hydrolytic cleavage of unmethylated lncRNA. The cleaved lncRNA fails to trigger the subsequent catalytic hairpin assembly (CHA) reaction due to the energy barrier. In contrast, when m6A-lncRNA is present, the methyl group in m6A protects lncRNA from VMC10-mediated cleavage. With the aid of an assistant probe, the retained intact m6A-lncRNA is released from the VMC10/lncRNA complex and subsequently triggers the CHA reaction, generating abundant AF647/biotin dual-labeled duplexes. The assembly of AF647/biotin dual-labeled duplexes onto 605QD results in efficient FRET between 605QD and AF647. The FRET signal can be simply quantified by single-molecule detection. Notably, this assay can be implemented in an antibody-free and enzyme-free manner. This nanosensor can sensitively quantify target m6A with a detection limit of 0.47 fM, and it can discriminate as low as a 0.001% m6A level from excess coexisting counterparts. Importantly, this nanosensor can monitor the cellular m6A level with single-cell sensitivity and profile target m6A expression in breast cancer and healthy para-cancerous tissues, providing a powerful tool for studying the physiological and pathological functions of m6A.

DOI: https://doi.org/10.1021/acs.analchem.3c04571
FASEB J. 2023 Dec;37(12): e23302

AGAP2-AS1 promotes the assembly of m6A methyltransferases and activation of the IL6/STAT3 pathway by binding with WTAP in the carcinogenesis of gastric cancer.

Kechao Nie, Zhihua Zheng, Jing Li, Yonglong Chang, Zhitong Deng, Wei Huang, Xiushen Li.

  Owing to the lack of biomarkers for early diagnosis, gastric cancer (GC) is often associated with a poor prognosis. Thus, there is an urgent need to identify early molecular targets in GC. Dysregulated long noncoding RNAs (lncRNAs) have been evaluated by integrated bioinformatics analysis; and we investigate their specific role and potential mechanism via N6-methyladenosine (m6A) methylation modification in the carcinogenesis and progression of GC. In this study, we report upregulation of lncRNA AGAP2-AS1, activated by a gain of H3K4Me3, in GC tissues and cells. AGAP2-AS1 was linked to adverse prognosis in patients with GC. Functionally, AGAP2-AS1 knockdown inhibited cell proliferation and migration of GC cells. Mechanistically, AGAP2-AS1 bound WT1-associated protein (WTAP) to promote the formation of the WTAP/methyltransferase-like 3 (METTL3)/METTL14 m6A methyltransferase complex. AGAP2-AS1 stabilized signal transducer and activator of transcription 3 (STAT3) mRNA in an m6A-dependent manner and, thus, activated the interleukin 6 (IL6)/STAT3 pathway. Importantly, activation of the AGAP2-AS1/WTAP/STAT3 pathways promoted cell proliferation and migration in GC. Collectively, the present findings revealed a novel regulatory relationship between lncRNA and m6A modification. Furthermore, targeting the AGAP2-AS1/WTAP/STAT3 axis may be a promising strategy for the inhibition of inflammation-mediated carcinogenesis and progression in GC.

Keywords:  AGAP2-AS1; N6-methyladenosine; STAT3; gastric cancer; inflammation

DOI:  https://doi.org/10.1096/fj.202301249R
J Med Chem. 2023 Nov 20.

Discovery of Pyrazolo[1,5-a]pyrimidine Derivative as a Novel and Selective ALKBH5 Inhibitor for the Treatment of AML.

Ying-Zhe Wang, Hong-Yu Li, Yan Zhang, Rui-Xin Jiang, Jun Xu, Jing Gu, Zheng Jiang, Zheng-Yu Jiang, Qi-Dong You, Xiao-Ke Guo.

M6A (N6-methyladenosine) plays a significant role in regulating RNA processing, splicing, nucleation, translation, and stability. AlkB homologue 5 (ALKBH5) is an Fe(II)/2-oxoglutarate (2-OG)-dependent dioxygenase that demethylates mono- or dimethylated adenosines. ALKBH5 can be regarded as an oncogenic factor for various human cancers. However, the discovery of potent and selective ALKBH5 inhibitors remains a challenge. We identified DDO-2728 as a novel and selective inhibitor of ALKBH5 by structure-based virtual screening and optimization. DDO-2728 was not a 2-oxoglutarate analogue and could selectively inhibit the demethylase activity of ALKBH5 over FTO. DDO-2728 increased the abundance of m6A modifications in AML cells, reduced the mRNA stability of TACC3, and inhibited cell cycle progression. Furthermore, DDO-2728 significantly suppressed tumor growth in the MV4-11 xenograft mouse model and showed a favorable safety profile. Collectively, our results highlight the development of a selective probe for ALKBH5 that will pave the way for the further study of ALKBH5 targeting therapies.

DOI: https://doi.org/10.1021/acs.jmedchem.3c01374
J Cardiovasc Pharmacol. 2023 Nov 17.

ALKBH5 regulates N(6)-methyladenosine (m6A) methylation of MG53 to attenuate myocardial infarction by inhibiting apoptosis and oxidative stress.

Dong Li, Lianggang Li, Shiyong Dong, Yaqun Yu, Lin Zhang, Shengli Jiang.

ABSTRACT: N(6)-methyladenosine (m6A) methylation modification is involved in the progression of myocardial infarction (MI). In this study, we investigated the effects of demethylase ALKBH5 on cell apoptosis and oxidative stress in MI. The ischemia/reperfusion (I/R) injury mouse model and hypoxia/reoxygenation (H/R) cell model were established. The levels of ALKBH5 and MG53 were measured by quantitative real-time polymerase chain reaction, immunohistochemical, and immunofluorescence analysis. Apoptosis was evaluated by TUNEL assay, flow cytometry, and western blot. Oxidative stress was assessed by antioxidant index kits. Methylation was analyzed by RNA binding protein immunoprecipitation (RIP), MeRIP, and dual-luciferase reporter assay. We observed that ALKBH5 and MG53 were highly expressed in MI. Overexpression of ALKBH5 inhibited H/R-induced cardiomyocyte apoptosis and oxidative stress in vitro, and inhibited I/R-induced collagen deposition, cardiac function, and apoptosis in vivo. ALKBH5 could bind to MG53, inhibit m6A methylation of MG53, and increase its mRNA stability. Silencing of MG53 counteracted the inhibition of apoptosis and oxidative stress induced by ALKBH5. In conclusion, ALKBH5 suppressed m6A methylation of MG53 and inhibited MG53 degradation to inhibit apoptosis and oxidative stress of cardiomyocytes, thereby attenuating MI. The results provided a theoretical basis that ALKBH5 is a potential target for MI treatment.

DOI: https://doi.org/10.1097/FJC.0000000000001515
Curr Issues Mol Biol. 2023 Oct 31. 45(11): 8767-8779

Identification of m6A Modification Regulated by Dysregulated circRNAs in Decidua of Recurrent Pregnancy Loss.

Liyuan Cui, Minfeng Shi, Xinhang Meng, Jinfeng Qian, Songcun Wang.

  N6-methyladenosine (m6A) modification is a prevalent modification of messenger ribonucleic acid (mRNA) in eukaryote cells and is closely associated with recurrent pregnancy loss (RPL). Circular RNAs (circRNAs) play critical roles in embryo implantation, trophoblast invasion and immune balance, which are important events during pregnancy. However, how m6A modification is regulated by circRNAs and the potential regulatory mechanism of circRNAs on RPL occurrence remain largely unclassified. We displayed the expression profiles of circRNAs and mRNAs in the decidua of normal pregnancies and RPL patients based on circRNA sequencing and the Gene Expression Omnibus database. A total of 936 differentially expressed circRNAs were identified, including 509 upregulated and 427 downregulated circRNAs. Differentially expressed circRNAs were enriched in immune, metabolism, signaling and other related pathways via the analysis of Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. The competitive endogenous RNA (ceRNA) network was predicted to supply the possible role of circRNAs in RPL occurrence, and we further analyzed the profiles of nine m6A regulators (seven readers, one writer and one eraser) managed by circRNAs in this network. We also showed the expression profiles of circRNAs in the serum, trying to seek a potential biomarker to help in the diagnosis of RPL. These data imply that circRNAs are involved in pathogenesis of RPL by changing immune activities, metabolism and m6A modification in the ceRNA network. Our study might provide assistance in exploring the pathogenesis and diagnosis of RPL.

Keywords:  ceRNA network; circRNAs; decidua; m6A modification; recurrent pregnancy loss; serum

DOI:  https://doi.org/10.3390/cimb45110551
J Exp Clin Cancer Res. 2023 Nov 21. 42(1): 306

m6A modified BACE1-AS contributes to liver metastasis and stemness-like properties in colorectal cancer through TUFT1 dependent activation of Wnt signaling.

Xidi Wang, Yu Liu, Miao Zhou, Lei Yu, Zizhen Si.

  BACKGROUND: Liver metastasis is one of the most important reasons for high mortality of colorectal cancer (CRC). Growing evidence illustrates that lncRNAs play a critical role in CRC liver metastasis. Here we described a novel function and mechanisms of BACE1-AS promoting CRC liver metastasis.METHODS: qRT-PCR and in situ hybridization were performed to examine the BACE1-AS level in CRC. IGF2BP2 binding to m6A motifs in BACE1-AS was determined by RIP assay and S1m-tagged immunoprecipitation. Transwell assay and liver metastasis mice model experiments were performed to examine the metastasis capabilities of BACE1-AS knockout cells. Stemness-like properties was examined by tumor sphere assay and the expression of stemness biomarkers. Microarray data were acquired to analyze the signaling pathways involved in BACE1-AS promoting CRC metastasis.
RESULTS: BACE1-AS is the most up-regulated in metastatic CRC associated with unfavorable prognosis. Sequence blast revealed two m6A motifs in BACE1-AS. IGF2BP2 binding to these two m6A motifs is required for BACE1-AS boost in metastatic CRC. m6A modified BACE1-AS drives CRC cells migration and invasion and liver metastasis both in vitro and in vivo. Moreover, BACE1-AS maintains the stemness-like properties of CRC cells. Mechanically, BACE1-AS promoted TUFT1 expression by ceRNA network through miR-214-3p. CRC patients with such ceRNA network suffer poorer prognosis than ceRNA-negative patients. Depletion of TUFT1 mimics BACE1-AS loss. BACE1-AS activated Wnt signaling pathway in a TUFT1 dependent manner. BACE1-AS/miR-214-3p/TUFT1/Wnt signaling regulatory axis is essential for CRC liver metastasis. Pharmacologic inhibition of Wnt signaling pathway repressed liver metastasis and stemness-like features in BACE1-AS over-expressed CRC cells.
CONCLUSION: Our study demonstrated BACE1-AS as a novel target of IGF2BP2 through m6A modification. m6A modified BACE1-AS promotes CRC liver metastasis through TUFT1 dependent activation of Wnt signaling pathway. Thus, targeting BACE1-AS and its downstream Wnt signaling pathways may provide a new opportunity for metastatic CRC intervention and treatment.

Keywords:  BACE1-AS; Colorectal cancer; Liver metastasis; TUFT1; m6A modification

DOI:  https://doi.org/10.1186/s13046-023-02881-0
Biotechnol Appl Biochem. 2023 Nov 20.

FTO-mediated ZNF687 accelerates tumor growth, metastasis, and angiogenesis in colorectal cancer through the Wnt/β-catenin pathway.

Junyi Li, Shixin Li, Xiaoxiao Xing, Nini Liu, Suyu Lai, Daixiang Liao, Jun Li.

  Colorectal cancer (CRC) is a common and lethal cancer. ZNF687 has been disclosed to take part in diversified cancers' progression by serving as a facilitator. However, the detailed regulatory functions of ZNF687 in the CRC have not been investigated. This work is planned to probe the impacts of ZNF687 on CRC progression. The IHC, RT-qPCR, and western blot assays were used to examine mRNA and protein gene expressions. The cell proliferation measurement was accompanied by a CCK-8 assay. The Transwell assay was performed to evaluate cell invasion and migration. The angiogenesis ability was evaluated by a tube formation experiment. The m6A level was evaluated through MeRIP and m6A dot blot assays. The binding ability between ZNF687 and FTO (fat mass and obesity associated protein) was tested through an RIP assay. The β-catenin nuclear translocation was assessed through an immunofluorescence assay. The tumor growth was evaluated through an in vivo assay. ZNF687 exhibited higher expression in CRC cells and resulted in a poor prognosis. Additionally, ZNF687 inhibition suppressed CRC cell proliferation, invasion, migration, and angiogenesis. Furthermore, the suppression of ZNF687 retarded the Wnt pathway. Through rescue assays, the reduced cell migration, proliferation, invasion, and angiogenesis mediated by ZNF687 knockdown could be reversed after BML-284 (the activator of the Wnt pathway) treatment. Finally, it was explained that ZNF687 knockdown inhibited in vivo tumor growth. This study manifested that FTO-mediated ZNF687 aggravated tumor growth, metastasis, and angiogenesis of CRC through Wnt/β-catenin pathway. This finding may provide a hopeful molecular target for CRC treatment.

Keywords:  FTO; Wnt/β-catenin pathway; ZNF687; angiogenesis; colorectal cancer

DOI:  https://doi.org/10.1002/bab.2536
Cells. 2023 Nov 10. pii: 2604. [Epub ahead of print]12(22):

ALKBH5 Stabilized N6-Methyladenosine-Modified LOC4191 to Suppress E. coli-Induced Apoptosis.

Haojun Xu, Changjie Lin, Chao Wang, Tianrui Zhao, Jinghan Yang, Junhao Zhang, Yanjun Hu, Xue Qi, Xi Chen, Yingyu Chen, Jianguo Chen, Aizhen Guo, Changmin Hu.

  E. coli is a ubiquitous pathogen that is responsible for over one million fatalities worldwide on an annual basis. In animals, E. coli can cause a variety of diseases, including mastitis in dairy cattle, which represents a potential public health hazard. However, the pathophysiology of E. coli remains unclear. We found that E. coli could induce global upregulation of m6A methylation and cause serious apoptosis in bovine mammary epithelial cells (MAC-T cells). Furthermore, numerous m6A-modified lncRNAs were identified through MeRIP-seq. Interestingly, we found that the expression of LOC4191 with hypomethylation increased in MAC-T cells upon E. coli-induced apoptosis. Knocking down LOC4191 promoted E. coli-induced apoptosis and ROS levels through the caspase 3-PARP pathway. Meanwhile, knocking down ALKBH5 resulted in the promotion of apoptosis through upregulated ROS and arrested the cell cycle in MAC-T cells. ALKBH5 silencing accelerated LOC4191 decay by upregulating its m6A modification level, and the process was recognized by hnRNP A1. Therefore, this indicates that ALKBH5 stabilizes m6A-modified LOC4191 to suppress E. coli-induced apoptosis. This report discusses an initial investigation into the mechanism of m6A-modified lncRNA in cells under E. coli-induced apoptosis and provides novel insights into infectious diseases.

Keywords:  E. coli; N6-methyladenosine; apoptosis; bovine mammary epithelial cells; long non-coding RNA

DOI:  https://doi.org/10.3390/cells12222604
Cancer Res. 2023 Nov 22.

SUMOylation-driven mRNA circularization enhances translation and promotes lymphatic metastasis of bladder cancer.

Yue Zhao, Jiancheng Chen, Hanhao Zheng, Yuming Luo, Mingjie An, Yan Lin, Mingrui Pang, Yuanlong Li, Yao Kong, Wang He, Tianxin Lin, Changhao Chen.

Aberrant gene expression is a prominent feature of metastatic cancer. Translational initiation is a vital step in fine-tuning gene expression. Thus, exploring translation initiation regulators may identify therapeutic targets for preventing and treating metastasis. Herein, we identified that DHCR24 was overexpressed in lymph node (LN) metastatic bladder cancer (BCa) and correlated with poor prognosis of patients. DHCR24 promoted lymphangiogenesis and LN metastasis of BCa in vitro and in vivo. Mechanistically, DHCR24 mediated and recognized the SUMO2 modification at lysine 108 of hnRNPA2B1 to foster TBK1 mRNA circularization and eIF4F initiation complex assembly by enhancing hnRNPA2B1-eIF4G1 interaction. Moreover, DHCR24 directly anchored to TBK1 mRNA 3'-untranslated region to increase its stability, thus forming a feedforward loop to elevate TBK1 expression. TBK1 activated PI3K/Akt signaling to promote VEGF-C secretion, resulting in lymphangiogenesis and LN metastasis. DHCR24 silencing significantly impeded BCa lymphangiogenesis and lymphatic metastasis in a patient-derived xenograft model. Collectively, these findings elucidate DHCR24-mediated translation machinery that promotes lymphatic metastasis of BCa and support the potential application of DHCR24-targeted therapy for LN-metastatic BCa.

DOI: https://doi.org/10.1158/0008-5472.CAN-23-2278
Cell Signal. 2023 Nov 17. pii: S0898-6568(23)00386-8. [Epub ahead of print]113 110971

METTL3 regulates the proliferation, metastasis and EMT progression of bladder cancer through P3H4.

Chun-Hui Liu, Jun-Jie Zhang, Qian-Jin Zhang, Yang Dong, Zhen-Duo Shi, Si-Hao Hong, Hou-Guang He, Wei Wu, Cong-Hui Han, Lin Hao.

  Bladder cancer, the most common malignant tumor in the urinary system, exhibits significantly up-regulated expression of P3H4, which is associated with pathological factors. The objective of this study was to elucidate the underlying mechanism of P3H4 in bladder cancer. Initially, we analyzed P3H4 gene expression using the TCGA database and evaluated P3H4 levels in clinical samples and various bladder cell lines. P3H4 was found to be markedly overexpressed in bladder cancer samples. Subsequently, bladder cancer cells were transfected with shRNA targeting P3H4 (sh-P3H4), sh-METTL3, and P3H4 overexpression vectors (P3H4 OE). Viability, migration, and invasion of bladder cancer cells were assessed using CCK-8, wound healing, and transwell assays. Western blot analysis was performed to determine the levels of EMT-associated proteins, while RNA stability assays determined the half-life of P3H4. Knockdown of P3H4 resulted in inhibition of bladder cancer cell proliferation, migration, invasion, and EMT progression. Mechanistically, METTL3 was found to regulate the mRNA stability of P3H4 in bladder cancer. Moreover, overexpression of P3H4 reversed the inhibitory effects of METTL3 knockdown on bladder cancer cell behaviors. Stable cell lines were established by infecting EJ cells with lentiviral vectors containing sh-METTL3 or P3H4 OE. These cells were then implanted into the skin of BALB/c nude mice, and IHC analysis was used to analyze the expression levels of EMT-associated proteins. In vivo studies demonstrated that inhibition of METTL3 suppressed bladder cancer growth and EMT through P3H4. In conclusion, our findings suggest that METTL3 regulates the proliferation, metastasis, and EMT progression of bladder cancer through P3H4, highlighting its potential as a therapeutic target.

Keywords:  Bladder cancer; EMT; METTL3; Metastasis; P3H4

DOI:  https://doi.org/10.1016/j.cellsig.2023.110971
Nutrients. 2023 Nov 15. pii: 4782. [Epub ahead of print]15(22):

Effects of Methionine Restriction from Different Sources on Sperm Quality in Aging Mice.

Yinghui Wu, Hao Li, Yueyue Miao, Jian Peng, Hongkui Wei.

  Decreased sperm quality causing poor pregnancy outcomes in aging males is a common problem. The aim of this study was to investigate the ameliorative effect of methionine restriction on sperm quality in aging mice, using methionine or 2-hydroxy-4-(methylthio)butanoate (HMTBA) as the methionine source, with a view to providing nutritional strategies to mitigate the decline in sperm quality in aging livestock. Fifty-one 6-week-old male mice were randomly divided into four groups: the non-aging group (NA, 0.86% methionine), the control diet group (CD, 0.86% methionine), the methionine-restricted group (MR, 0.17% methionine) and the HMTBA-restricted group (HR, 0.17% methionine). The mice in the CD, MR and HR groups were injected with a daily dose of 0.25 mL/20 g body weight of 10% D-galactose to establish an aging model. The test period was 42 days. The results showed that aging mice in the CD group had impaired testicular morphology and significantly decreased sperm quality compared to those in the NA group. Aging mice in the MR and HR groups showed attenuated impaired testicular morphology and improved sperm quality, especially sperm acrosomal integrity and membrane integrity, compared to mice in the CD group. In addition, mice in the MR and HR groups had reduced testicular inflammation and oxidative stress, increased spermidine levels, and reduced sperm RNA N6-methyladenosine (m6A) and DNA 5-methylcytosine (5mC) levels. Spermidine levels were positively correlated, whereas sperm RNA m6A and DNA 5mC levels were negatively correlated with sperm quality parameters. Our study suggests that methionine restriction alleviates the decline in sperm quality in aging mice, which may be related to changes in methionine metabolism and inhibition of sperm DNA and RNA methylation.

Keywords:  aging mice; methionine hydroxy analog; methionine restriction; methylation; sperm quality; spermidine

DOI:  https://doi.org/10.3390/nu15224782