bims-rimeca 2022-04-03 papers

bims-rimeca

Biomed News

on RNA methylation in cancer

Issue of 2022–04–03
eleven papers selected by
Sk Ramiz Islam, Saha Institute of Nuclear Physics

N6-methyladenosine methyltransferase WTAP-stabilized FOXD2-AS1 promotes the osteosarcoma progression through m6A/FOXM1 axis.
METTL3 promotes proliferation and myogenic differentiation through m6A RNA methylation/YTHDF1/2 signaling axis in myoblasts.
HNRNPA2B1 inhibited SFRP2 and activated Wnt-β/catenin via m6A-mediated miR-106b-5p processing to aggravate stemness in lung adenocarcinoma.
METTL14 promotes prostate tumorigenesis by inhibiting THBS1 via an m6A-YTHDF2-dependent mechanism.
RNA demethylase ALKBH5 inhibits TGF-β-induced EMT by regulating TGF-β/SMAD signaling in non-small cell lung cancer.
Cross-Talk Between m6A- and m5C-Related lncRNAs to Construct a Novel Signature and Predict the Immune Landscape of Colorectal Cancer Patients.
METTL3 enhances NSD2 mRNA stability to reduce renal impairment and interstitial fibrosis in mice with diabetic nephropathy.
Mettl14-Mediated m6A Modification Is Essential for Germinal Center B Cell Response.
Maslinic acid protects against pressure-overload-induced cardiac hypertrophy by blocking METTL3-mediated m6A methylation.
Vitamin D3 Suppresses Human Cytomegalovirus-Induced Vascular Endothelial Apoptosis via Rectification of Paradoxical m6A Modification of Mitochondrial Calcium Uniporter mRNA, Which Is Regulated by METTL3 and YTHDF3.
METTL3-mediated maturation of miR-589-5p promotes the malignant development of liver cancer.

Bioengineered. 2022 Apr;13(4): 7963-7973

N6-methyladenosine methyltransferase WTAP-stabilized FOXD2-AS1 promotes the osteosarcoma progression through m6A/FOXM1 axis.

Zhipeng Ren, Yongcheng Hu, Jie Sun, Yuxiang Kang, Guishi Li, Hejun Zhao.

  Long noncoding RNAs (lncRNAs) play critical roles in tumor progression regulation, including osteosarcoma. Evidence indicates that N6-methyladenosine (m6A) modification modulates mRNA stability to regulate osteosarcoma tumorigenesis. Here, present research aims to detect the roles of m6A-modified lncRNA FOXD2-AS1 in the osteosarcoma pathophysiological process. Clinical data unveiled that osteosarcoma patients with higher FOXD2-AS1 expression had a poorer overall survival rate compared to those with lower FOXD2-AS1 expression. Functional research illuminated that FOXD2-AS1 accelerated the migration, proliferation and tumor growth in vitro and in vivo. Mechanistically, a remarkable m6A-modified site was found on the 3'-UTR of FOXD2-AS1, and m6A methyltransferase WTAP (Wilms' tumor 1 associated protein) promoted the methylation modification, thus enhancing the stability of FOXD2-AS1 transcripts. Furthermore, FOXD2-AS1 interacted with downstream target FOXM1 mRNA through m6A sites, forming a FOXD2-AS1/m6A/FOXM1 complex to heighten FOXM1 mRNA stability. In conclusion, these findings propose a novel regulatory mechanism in which m6A-modified FOXD2-AS1 accelerates the osteosarcoma progression through m6A manner, which may provide new concepts for osteosarcoma tumorigenesis.

Keywords:  N6-methyladenosine; Osteosarcoma; WTAP; foxd2-as1; foxm1

DOI:  https://doi.org/10.1080/21655979.2021.2008218
Life Sci. 2022 Mar 26. pii: S0024-3205(22)00196-5. [Epub ahead of print]298 120496

METTL3 promotes proliferation and myogenic differentiation through m6A RNA methylation/YTHDF1/2 signaling axis in myoblasts.

Tiantian Zhao, Rui Zhao, Xudong Yi, Rui Cai, Weijun Pang.

  Skeletal muscle development has an important impact on muscle-related diseases and domestic animal meat production. The m6A RNA methylation is a common post-transcriptional modification, affecting the development and metabolism of various organs. However, the effect and regulatory mechanism of methyltransferase like 3 (METTL3) on myogenesis are still unclear. Here, we showed that the mRNA levels of METTL3 was greater in skeletal muscles including extensor digitorum longus (EDL), soleus (SOL), tibialis anterior (TA) and gastrocnemius (GAS). Moreover, METTL3 highly expressed in the early stage of myoblast proliferation at hour 0 and the late stage of myoblast differentiation at day 8, indicating it was involved in myogenesis. Interestingly, METTL3 knockdown inhibited myoblast proliferation and myogenic differentiation, whereas METTL3 overexpression promoted these processes. Mechanically, METTL3 overexpression increased the ratio of mRNA m6A/A and shortened the time of P21 and P27 mRNA half level, causing the mRNAs downregulation via reducing their stability. Meanwhile, the promotion of cell proliferation by METTL3 overexpression was attenuated by YTH N6-methyladenosine RNA binding protein 2 (YTHDF2) knockdown. Furthermore, the promotion of myogenic differentiation by METTL3 overexpression was weakened by YTHDF1 knockdown through reducing the mRNA translation of MRFs including MyHC, MyoD and MyoG. Therefore, METTL3 facilitates myoblast proliferation and myogenic differentiation. Overall, these findings suggest that METTL3/m6A RNA methylation/YTHDF1/2 signaling axis is a novel strategy for the regulation of skeletal muscle development.

Keywords:  METTL3; Myoblast; Myogenic differentiation; Proliferation; YTHDF1/2; m(6)A RNA methylation

DOI:  https://doi.org/10.1016/j.lfs.2022.120496
Pathol Res Pract. 2022 Feb 10. pii: S0344-0338(22)00037-1. [Epub ahead of print]233 153794

HNRNPA2B1 inhibited SFRP2 and activated Wnt-β/catenin via m6A-mediated miR-106b-5p processing to aggravate stemness in lung adenocarcinoma.

Liang Rong, Yichen Xu, Kai Zhang, Lei Jin, Xiaobei Liu.

  Cancer stem cells (CSCs) exhibit strong self-renewal capability to contribute to tumorigenesis in lung adenocarcinoma (LUAD). N6-methyladenosine (m6A) methylation is confirmed as a key mechanism for stemness acquisition and tumor growth. Heterogeneous nuclear ribonucleoprotein A2B1 (HNRNPA2B1) is a known m6A reader and is reported to participate in LUAD progression, but its relation with stemness of LUAD cells is unknown. Thus, this study aimed to uncover the effect of HNRNPA2B1 in stemness of LUAD cells. The association of HNRNPA2B1 with LUAD prognosis was analyzed via Gene Expression Profiling Interactive Analysis (GEPIA). Sphere formation, cytometry flow analysis and western blot of stemness-related genes were performed to examine the stemness of LUAD cells. m6A modification was investigated by RNA immunoprecipitation. Results depicted that HNRNPA2B1 was upregulated in LUAD CSCs. HNRNPA2B1 knockdown repressed cell stemness, proliferation, migration, and tumor growth of LUAD. As to mechanism, HNRNPA2B1 read the m6A site on primary microRNA-106b (pri-miR-106b) to facilitate the maturing of miR-106b-5p, so that miR-106b-5p targeted secreted frizzled-related protein 2 (SFRP2), activating Wnt/β-catenin signaling. In conclusion, HNRNPA2B1 inhibits SFRP2 and activates Wnt-β/catenin via m6A-mediated maturing of miR-106b-5p to aggravate stemness and LUAD progression, which potentially offered HNRNPA2B1 as a potential marker in CSCs-targeted treatment for LUAD.

Keywords:  Cancer stem cells; HNRNPA2B1; Lung adenocarcinoma; M6A; MiR-106b-5p; SFRP2

DOI:  https://doi.org/10.1016/j.prp.2022.153794
Cell Death Discov. 2022 Mar 30. 8(1): 143

METTL14 promotes prostate tumorigenesis by inhibiting THBS1 via an m6A-YTHDF2-dependent mechanism.

Yongjie Wang, Junfei Chen, Wei-Qiang Gao, Ru Yang.

N6-methyladenine (m6A) is the most predominant RNA modification, which has been shown to be related to many types of cancers. However, understanding of its role in prostate cancer (PCa) is largely unknown. Here, we report an upregulation of METTL14 that was correlated with poor prognosis in PCa patients. Functionally, knocking down METTL14 inhibited tumor proliferation both in vitro and in vivo. Mechanically, RNA-seq and MeRIP-seq analyses identified THBS1 as the downstream target of METTL14 in PCa. METTL14 downregulated THBS1 expression in an m6A-dependent manner, which resulted in the recruitment of YTHDF2 to recognize and degrade Thrombospondin 1 (THBS1) mRNA. Thus, our findings revealed that METTL14 acted as an oncogene by inhibiting THBS1 expression via an m6A-YTHDF2-dependent manner. METTL14 could be a potential prognosis marker and a therapeutic target.

DOI: https://doi.org/10.1038/s41420-022-00939-0
FASEB J. 2022 May;36(5): e22283

RNA demethylase ALKBH5 inhibits TGF-β-induced EMT by regulating TGF-β/SMAD signaling in non-small cell lung cancer.

Zelong Sun, Zhiyue Su, Zhengyu Zhou, Shengjie Wang, Zhao Wang, Xin Tong, Chang Li, Yuxin Wang, Xiaoyan Chen, Zhe Lei, Hong-Tao Zhang.

  AlkB homolog 5 (ALKBH5) has been revealed as a key RNA N6 -methyladenosine (m6 A) demethylase that is implicated in development and diseases. However, the function of ALKBH5 in TGF-β-induced epithelial-mesenchymal transition (EMT) and tumor metastasis of non-small-cell lung cancer (NSCLC) remains unknown. Here, we firstly show that ALKBH5 expression is significantly reduced in metastatic NSCLC. ALKBH5 overexpression inhibits TGF-β-induced EMT and invasion of NSCLC cells, whereas ALKBH5 knockdown promotes the corresponding phenotypes. ALKBH5 overexpression suppresses TGF-β-stimulated NSCLC cell metastasis in vivo. ALKBH5 overexpression decreases the expression and mRNA stability of TGFβR2 and SMAD3 but increases those of SMAD6, while ALKBH5 knockdown causes the opposite results. Importantly, ALKBH5 overexpression or knockdown leads respectively to an attenuated or augmented phosphorylation of SMAD3, an indispensable downstream effector that activates TGF-β/SMAD signaling. Moreover, m6 A-binding proteins YTHDF1/3 promotes TGFβR2 and SMAD3 expression, and YTHDF2 inhibits SMAD6 expression. YTHDF1/2/3 facilitates TGF-β-stimulated EMT and invasion of NSCLC cells. Mechanistically, ALKBH5 affects TGFβR2, SMAD3 and SMAD6 expression and mRNA stability by erasing m6 A modification in NSCLC cells. ALKBH5 weakens YTHDF1/3-mediated TGFβR2 and SMAD3 mRNA stabilization, and abolishes YTHDF2-mediated SMAD6 mRNA degradation, supporting the notion that ALKBH5 inhibits TGF-β-induced EMT and invasion of NSCLC cells via YTHD1/2/3-mediated mechanism. Taken together, our findings highlight an important role of ALKBH5 in regulating TGF-β/SMAD signaling, and establish a mechanistic interaction of ALKBH5 with TGFβR2/SMAD3/SMAD6 for controlling TGF-β-induced EMT in NSCLCs.

Keywords:  ALKBH5; NSCLC; TGF-β-induced EMT; YTHDF1/2/3; m6A

DOI:  https://doi.org/10.1096/fj.202200005RR
Front Immunol. 2022 ;13 740960

Cross-Talk Between m6A- and m5C-Related lncRNAs to Construct a Novel Signature and Predict the Immune Landscape of Colorectal Cancer Patients.

Wei Song, Jun Ren, Rensheng Xiang, Wenzheng Yuan, Tao Fu.

   Background: N6-methyladenosine (m6A) and 5-methylcytosine (m5C) can modify long non-coding RNAs (lncRNAs), thereby affecting tumorigenesis and tumor progression. However, there is a lack of knowledge regarding the potential roles and cross-talk of m6A- and m5C-related lncRNAs in the tumor microenvironment (TME) and their effect on prognosis.
Methods: We systematically evaluated the expression patterns of m6A- and m5C-related lncRNAs in 1358 colorectal cancer (CRC) samples from four datasets. Consensus clustering was conducted to identify molecular subtypes of CRC, and the clinical significance, TME, tumor-infiltrating immune cells (TIICs), and immune checkpoints in the different molecular subtypes were analyzed. Finally, we established a m6A- and m5C-related lncRNA signature and a prognostic nomogram.
Results: We identified 141 m6A- and m5C-related lncRNAs by co-expression analysis, among which 23 lncRNAs were significantly associated with the overall survival (OS) of CRC patients. Two distinct molecular subtypes (cluster A and cluster B) were identified, and these two distinct molecular subtypes could predict clinicopathological features, prognosis, TME stromal activity, TIICs, immune checkpoints. Next, a m6A- and m5C-related lncRNA signature for predicting OS was constructed, and its predictive capability in CRC patients was validated. We then constructed a highly accurate nomogram for improving the clinical applicability of the signature. Analyses of clinicopathological features, prognosis, TIICs, cancer stem cell (CSC), and drug response revealed significant differences between two risk groups. In addition, we found that patients with a low-risk score exhibited enhanced response to anti-PD-1/L1 immunotherapy. Functional enrichment analysis showed that these lncRNAs related to the high-risk group were involved in the development and progression of CRC.
Conclusions: We conducted a comprehensive analysis of m6A- and m5C-related lncRNAs in CRC and revealed their potential functions in predicting tumor-immune-stromal microenvironment, clinicopathological features, and prognosis, and determined their role in immunotherapy. These findings may improve our understanding of the cross-talk between m6A- and m5C-related lncRNAs in CRC and pave a new road for prognosis assessment and more effective immunotherapy strategies.

Keywords:  colorectal cancer; immunotherapy; long non-coding RNA; m5C regulators; m6A regulators; tumor microenvironment

DOI:  https://doi.org/10.3389/fimmu.2022.740960
BMC Nephrol. 2022 Mar 30. 23(1): 124

METTL3 enhances NSD2 mRNA stability to reduce renal impairment and interstitial fibrosis in mice with diabetic nephropathy.

Weiming Tang, Yilin Zhao, Hui Zhang, Ying Peng, Zhilian Rui.

   BACKGROUND: Nuclear receptor-binding SET domain protein 2 (NSD2) is a histone methyltransferase that has been demonstrated to regulate insulin secretion and glucose concentration. This study focused on the role of NSD2 in the renal impairment during diabetic nephropathy (DN).
METHODS: Serum NSD2 level in patients with DN was examined, and its correlations with the renal impairment-related indicators were examined. A murine model of DN was established, and mouse mesangial cells (SV40-MES-13) were treated with high-glucose (HG) to mimic a DN-like condition in vitro. Overexpression of NSD2 was introduced into mice or cells for in vivo and in vitro studies. The m6A level in HG-treated SV40-MES-13 cells was analyzed. METTL3 expression and its correlation with NSD2 were determined.
RESULTS: NSD2 was poorly expressed in the serum of patients with DN and was negatively correlated with the levels of fasting blood sugar (FBG), serum creatinine (SCr), serum cystatin C (S-Cys-C), the 24-h urine protein (24-h U-protein) and the urine cystatin C (U-Cys-C). NSD2 overexpression reduced the kidney weight and reduced renal impairment in mice. It also suppressed interstitial fibrosis in mouse kidney tissues and reduced fibrosis-related markers in HG-treated SV40-MES-13 cells. HG treatment reduced the m6A level in the cells. METTL3 promoted m6A modification of NDS2 mRNA and enhanced its stability by YTHDF1. METTL3 overexpression alleviated renal impairment and fibrosis in vivo and in vitro. But the protective role was blocked upon NSD2 silencing.
CONCLUSION: This study demonstrates that METTL3 promotes NSD2 mRNA stability by YTHDF1 to alleviate progression of DN.

Keywords:  Diabetic nephropathy; Interstitial fibrosis; METTL3; NSD2; YTHDF1

DOI:  https://doi.org/10.1186/s12882-022-02753-3
J Immunol. 2022 Apr 01. pii: ji2101071. [Epub ahead of print]

Mettl14-Mediated m6A Modification Is Essential for Germinal Center B Cell Response.

Hengjun Huang, Gaopu Zhang, Gui-Xin Ruan, Yuxing Li, Wenjing Chen, Jia Zou, Rui Zhang, Jing Wang, Sheng-Jian Ji, Shengli Xu, Xijun Ou.

The germinal center (GC) response is essential for generating memory B and long-lived Ab-secreting plasma cells during the T cell-dependent immune response. In the GC, signals via the BCR and CD40 collaboratively promote the proliferation and positive selection of GC B cells expressing BCRs with high affinities for specific Ags. Although a complex gene transcriptional regulatory network is known to control the GC response, it remains elusive how the positive selection of GC B cells is modulated posttranscriptionally. In this study, we show that methyltransferase like 14 (Mettl14)-mediated methylation of adenosines at the position N 6 of mRNA (N 6-methyladenosine [m6A]) is essential for the GC B cell response in mice. Ablation of Mettl14 in B cells leads to compromised GC B cell proliferation and a defective Ab response. Interestingly, we unravel that Mettl14-mediated m6A regulates the expression of genes critical for positive selection and cell cycle regulation of GC B cells in a Ythdf2-dependent but Myc-independent manner. Furthermore, our study reveals that Mettl14-mediated m6A modification promotes mRNA decay of negative immune regulators, such as Lax1 and Tipe2, to upregulate genes requisite for GC B cell positive selection and proliferation. Thus, our findings suggest that Mettl14-mediated m6A modification plays an essential role in the GC B cell response.

DOI: https://doi.org/10.4049/jimmunol.2101071
Aging (Albany NY). 2022 Mar 28. 14(undefined):

Maslinic acid protects against pressure-overload-induced cardiac hypertrophy by blocking METTL3-mediated m6A methylation.

Ming Fang, Jun Deng, Qiangping Zhou, Zhengbang Hu, Lixia Yang.

  Coordinated response of the heart to physiological stressors (including stress overload, ischemia, hypothyroidism, and metabolic signals) is a hallmark of heart disease. However, effective treatment and its molecular targets are unknown. Although Maslinic Acid (MA) has been shown to inhibit inflammatory responses with strong anti-tumor, anti-bacterial, and antioxidant effects, information on its role and underlying mechanism in cardiac hypertrophy are scanty. The present study revealed that 10-103 μg/ml MA treatment significantly inhibited Ang-II induced hypertrophy in NMCMs and the dosage did not influence the cell viability of H9C2 and NCMCs. Moreover, the anti-hypertrophy effect of MA (30 mg/kg·day) was verified in the TAC-induced hypertrophy mouse model in vivo. Further analysis showed that MA administration decreased the total RNA m6A methylation and METTL3 levels in Ang-II treated NMCMs and TAC stressed hearts. Rescue experiments under adenovirus-mediated myocardial METTL3 overexpression confirmed that METTL3-mediated m6A methylation is essential in M-driven inhibition of myocardial hypertrophy. Collectively, MA exerts a significant anti-hypertrophy effect by regulating the modification of METTL3-mediated m6A methylation in vitro and in vivo. These findings may provide a platform for establishing a new target and strategy for cardiac hypertrophy treatment.

Keywords:  N6-methyladenosine (m6A); maslinic acid (MA); methyltransferase-like 3 (METTL3); myocardial hypertrophy

DOI:  https://doi.org/10.18632/aging.203860
Front Microbiol. 2022 ;13 861734

Vitamin D3 Suppresses Human Cytomegalovirus-Induced Vascular Endothelial Apoptosis via Rectification of Paradoxical m6A Modification of Mitochondrial Calcium Uniporter mRNA, Which Is Regulated by METTL3 and YTHDF3.

Wenbo Zhu, Hongbo Zhang, Shao Wang.

  Human cytomegalovirus (HCMV) infection can induce apoptosis of vascular endothelial cells, which may be the most important element of development and progression of reported atherosclerosis caused by HCMV. As there are no specific drugs to clear HCMV infection, exploration of relevant drugs and mechanisms that can intervene in HCMV-induced atherosclerosis is urgently needed. The present study confirmed that vitamin D3 protected vascular endothelial cells from HCMV-induced apoptosis by inhibiting endoplasmic reticulum (ER) and mitochondrial apoptosis pathway. Mechanistically, HCMV infection could induce aberrantly elevated m6A modification, especially the increases of methyltransferases-"writers" (METTL3) and m6A binding proteins-"readers" (YTHDF3). METTL3 methylates mitochondrial calcium uniporter (MCU), the main contributor to HCMV-induced apoptosis of vascular endothelial cells, at three m6A residues in the 3'-UTR, which promotes the association of the YTHDF3 with methylated MCU mRNA and subsequently increases the translation and expression of MCU. Further analysis shows that ALKBH5 is the demethylases-"eraser" of MCU mRNA, which can negatively regulate the m6A modification process of MCU. Conversely, vitamin D3 downregulated the METTL3 by inhibiting the activation of AMPK, thereby inhibiting the m6A modification of MCU and cell apoptosis. Our findings extend the understanding of m6A driven machinery in virus-induced vascular endothelium damage and highlight the significance of vitamin D3 in the intervention of HCMV-induced atherosclerosis.

Keywords:  HCMV; MCU; apoptosis; m6A modification; vascular endothelial cells

DOI:  https://doi.org/10.3389/fmicb.2022.861734
J Cell Mol Med. 2022 Mar 29.

METTL3-mediated maturation of miR-589-5p promotes the malignant development of liver cancer.

Jie Liu, Kai Jiang.

  MiR-589-5p could promote liver cancer, but the specific mechanisms are largely unknown. This study examined the role and mechanisms of miR-589-5p in liver cancer. The expressions of miR-589-5p, METTL3 and m6A in liver cancers were determined by RT-qPCR. The relationship between miR-589-5p and METTL3-mediated m6A methylation was examined by m6A RNA immunoprecipitation. After transfection, the viability, migration, invasion and expressions of METTL3 and miR-589-5p in liver cancer cells were detected by CCK-8, wound-healing, transwell and RT-qPCR. After the xenograft tumour was established in mice, the tumour volume was determined and the expressions of METTL3, miR-589-5p, MMP-2, TIMP-2, E-cadherin, N-cadherin and Vimentin in tumour tissue were detected by RT-qPCR and Western blotting. In vitro study showed that miR-589-5p and METTL3 were highly expressed in liver cancer. METTL3 was positively correlated with miR-589-5p. METTL3 up-regulated the expression of miR-589-5p and promoted the maturation of miR-589-5p. Overexpressed miR-589-5p and METTL3 promoted the viability, migration and invasion of liver cancer cells, while the effects of silencing miR-589-5p and METTL3 on the cells were the opposite. The effects of METTL3 overexpression and silencing were reversed by miR-589-5p inhibitor and mimic, respectively. In vivo study showed that METLL3 silencing inhibited the growth of xenograft tumour and the expressions of METTL3, MMP-2, N-cadherin and Vimentin, promoted the expressions of TIMP-2 and E-cadherin, while miR-589-5p mimic caused the opposite results and further reversed the effects of METLL3 silencing. In summary, this study found that METTL3-mediated maturation of miR-589-5p promoted the malignant development of liver cancer.

Keywords:  METTL3; liver cancer; m6A methylation; miR-589-5p; pri-miR-589

DOI:  https://doi.org/10.1111/jcmm.16845