Dataset Information

METTL3 facilitates tumor progression via an m⁶A-IGF2BP2-dependent mechanism in colorectal carcinoma.

ABSTRACT:

Background

Colorectal carcinoma (CRC) is one of the most common malignant tumors, and its main cause of death is tumor metastasis. RNA N⁶-methyladenosine (m⁶A) is an emerging regulatory mechanism for gene expression and methyltransferase-like 3 (METTL3) participates in tumor progression in several cancer types. However, its role in CRC remains unexplored.

Methods

Western blot, quantitative real-time PCR (RT-qPCR) and immunohistochemical (IHC) were used to detect METTL3 expression in cell lines and patient tissues. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and transcriptomic RNA sequencing (RNA-seq) were used to screen the target genes of METTL3. The biological functions of METTL3 were investigated in vitro and in vivo. RNA pull-down and RNA immunoprecipitation assays were conducted to explore the specific binding of target genes. RNA stability assay was used to detect the half-lives of the downstream genes of METTL3.

Results

Using TCGA database, higher METTL3 expression was found in CRC metastatic tissues and was associated with a poor prognosis. MeRIP-seq revealed that SRY (sex determining region Y)-box 2 (SOX2) was the downstream gene of METTL3. METTL3 knockdown in CRC cells drastically inhibited cell self-renewal, stem cell frequency and migration in vitro and suppressed CRC tumorigenesis and metastasis in both cell-based models and PDX models. Mechanistically, methylated SOX2 transcripts, specifically the coding sequence (CDS) regions, were subsequently recognized by the specific m⁶A "reader", insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2), to prevent SOX2 mRNA degradation. Further, SOX2 expression positively correlated with METTL3 and IGF2BP2 in CRC tissues. The combined IHC panel, including "writer", "reader", and "target", exhibited a better prognostic value for CRC patients than any of these components individually.

Conclusions

Overall, our study revealed that METTL3, acting as an oncogene, maintained SOX2 expression through an m⁶A-IGF2BP2-dependent mechanism in CRC cells, and indicated a potential biomarker panel for prognostic prediction in CRC.

SUBMITTER: Li T

PROVIDER: S-EPMC6589893 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Publications

METTL3 facilitates tumor progression via an m<sup>6</sup>A-IGF2BP2-dependent mechanism in colorectal carcinoma.

Li Ting T Hu Pei-Shan PS Zuo Zhixiang Z Lin Jin-Fei JF Li Xingyang X Wu Qi-Nian QN Chen Zhan-Hong ZH Zeng Zhao-Lei ZL Wang Feng F Zheng Jian J Chen Demeng D Li Bo B Kang Tie-Bang TB Xie Dan D Lin Dongxin D Ju Huai-Qiang HQ Xu Rui-Hua RH

Molecular cancer 20190624 1

<h4>Background</h4>Colorectal carcinoma (CRC) is one of the most common malignant tumors, and its main cause of death is tumor metastasis. RNA N<sup>6</sup>-methyladenosine (m<sup>6</sup>A) is an emerging regulatory mechanism for gene expression and methyltransferase-like 3 (METTL3) participates in tumor progression in several cancer types. However, its role in CRC remains unexplored.<h4>Methods</h4>Western blot, quantitative real-time PCR (RT-qPCR) and immunohistochemical (IHC) were used to det ...[more]

PMID: 31230592

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Project description:As the key enzyme of the N6-methyladenosine (m6A) in eukaryotic messenger RNA, METTL3 plays an important role in tumor progression, but the exact mechanism by which METTL3 controls oral squamous cell carcinoma (OSCC) progression remains unclear. In this study, METTL3 expression in OSCC samples was analyzed by qPCR and immunohistochemistry. The effects of METTL3 suppression on OSCC cell lines were measured by CCK-8, Ki67 flow cytometry analysis, invasion transwell and wound healing assays. MeRIP-seq and RNA-seq analyses were performed to explore target gene of METTL3. RIP-qPCR and RNA stability assays were performed to explore the mechanism by which METTL3 regulated the target genes. Triptolide was used to evaluate its specific treatment effects on METTL3 in OSCC cells. BALB/c nude mice were used to establish orthotopic and subcutaneous xenograft models to verify the in vitro results. The results showed that METTL3 was upregulated in OSCC tissues compared with OSCC adjacent normal tissues, and its expression was associated with T stage, lymphatic metastasis and prognosis. METTL3 suppression impaired OSCC cells proliferation, invasion, and migration. MeRIP-seq and RNA-seq analysis identified that SLC7A11 mRNA was the m6A target of METTL3, which was verified by meRIP-qPCR, qPCR and western blot. METTL3 depletion decreased the stability of SLC7A11 mRNA, and IGF2BP2 as m6A reader was involved in this process. Moreover, METTL3 knockdown attenuated the binding between SLC7A11 mRNA and IGF2BP2, finally leading to accelerate SLC7A11 mRNA degradation. Triptolide inhibited METTL3-mediated SLC7A11 expression, thus suppressing malignancy of OSCC cells. In conclusion, the new finding of the manuscript is that METTL3 enhances the mRNA stability of SLC7A11 via m6A-mediated binding of IGF2BP2, which thus promotes OSCC progression, and triptolide inhibits OSCC by suppressing METTL3-SLC7A11 axis. Triptolide has a potential to be as an effective anti-OSCC drug targeted to METTL3.

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Dataset Information

METTL3 facilitates tumor progression via an m⁶A-IGF2BP2-dependent mechanism in colorectal carcinoma.

Background

Methods

Results

Conclusions

Publications

METTL3 facilitates tumor progression via an m<sup>6</sup>A-IGF2BP2-dependent mechanism in colorectal carcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

METTL3 facilitates tumor progression via an m6A-IGF2BP2-dependent mechanism in colorectal carcinoma.

Background

Methods

Results

Conclusions

Publications

METTL3 facilitates tumor progression via an m<sup>6</sup>A-IGF2BP2-dependent mechanism in colorectal carcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

METTL3 facilitates tumor progression via an m⁶A-IGF2BP2-dependent mechanism in colorectal carcinoma.