RNA m6A 阅读蛋白 YTHDC1 对三阴性乳腺癌 TGF-β 介导的转移至关重要。

RNA -methyladenosine reader YTHDC1 is essential for TGF-beta-mediated metastasis of triple negative breast cancer.

机构信息

Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA.

Department of Immunology, School of Basic Medicine, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, Hebei 050017, China.

出版信息

Theranostics. 2022 Jul 18;12(13):5727-5743. doi: 10.7150/thno.71872. eCollection 2022.

DOI:10.7150/thno.71872

PMID:35966596

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9373808/

Abstract

UNLABELLED

RNA -methyladenosine (mA) modification and its regulators fine tune gene expression and contribute to tumorigenesis. This study aims to uncover the essential role and the underlying molecular mechanism(s) of the mA reader YTHDC1 in promoting triple negative breast cancer (TNBC) metastasis.

METHODS

and models were employed to determine the pathological function of in TNBC metastasis. To identify YTHDC1 target RNAs, we conducted RNA-seq, mA-seq, and RIP-seq, followed by integrative data analysis and validation assays.

RESULTS

By analyzing The Cancer Genome Atlas (TCGA) dataset, we found that elevated expression of is positively correlated with poor prognosis in breast cancer patients. Using a mammary fat pad mouse model of TNBC, significantly promoted lung metastasis of TNBC cells. Through multiple transcriptome-wide sequencing and integrative data analysis, we revealed dysregulation of metastasis-related pathways following YTHDC1 depletion and identified SMAD3 as a bona fide YTHDC1 target RNA. Depletion of YTHDC1 caused nuclear retention of mRNA, leading to lower SMAD3 protein levels. Loss of YTHDC1 led to impaired TGF-β-induced gene expression, leading to inhibition of epithelial-mesenchymal transition (EMT) and suppressed TNBC cell migration and invasion. SMAD3 overexpression was able to restore the response to TGF-β in YTHDC1 depleted TNBC cells. Furthermore, we demonstrated that the oncogenic role of YTHDC1 is mediated through its recognition of mA as mA-binding defective mutants of YTHDC1 were unable to rescue the impaired cell migration and invasion of YTHDC1 knockout TNBC cells.

CONCLUSIONS

We show that YTHDC1 plays a critical oncogenic role in TNBC metastasis through promoting the nuclear export and expression of to augment the TGF-β signaling cascade. Overall, our study demonstrates that YTHDC1 is vital for TNBC progression by enhancing TNBC cell survival and TGF-β-mediated EMT via SMAD3 to enable the formation of distant metastasis and highlights the therapeutic potential of targeting the YTHDC1/mA/SMAD3 axis for TNBC treatment.

摘要

目的

本研究旨在揭示 mA 阅读器 YTHDC1 在促进三阴性乳腺癌（TNBC）转移中的关键作用和潜在分子机制。

方法

采用体外和体内模型来确定 YTHDC1 在 TNBC 转移中的病理功能。为了鉴定 YTHDC1 的靶 RNA，我们进行了 RNA-seq、mA-seq 和 RIP-seq，随后进行了整合数据分析和验证实验。

结果

通过分析癌症基因组图谱（TCGA）数据集，我们发现 YTHDC1 的表达升高与乳腺癌患者的预后不良呈正相关。在 TNBC 的乳腺脂肪垫小鼠模型中，YTHDC1 显著促进了 TNBC 细胞的肺转移。通过多种转录组全测序和整合数据分析，我们发现 YTHDC1 耗竭后会导致转移相关通路的失调，并鉴定出 SMAD3 是 YTHDC1 的一个真正的靶 RNA。YTHDC1 耗竭导致 mRNA 的核内滞留，从而降低 SMAD3 蛋白水平。YTHDC1 的缺失导致 TGF-β 诱导的基因表达受损，从而抑制上皮-间充质转化（EMT），并抑制 TNBC 细胞的迁移和侵袭。SMAD3 的过表达能够恢复 YTHDC1 缺失的 TNBC 细胞对 TGF-β 的反应。此外，我们证明 YTHDC1 的致癌作用是通过其识别 mA 来介导的，因为 YTHDC1 的 mA 结合缺陷突变体无法挽救 YTHDC1 敲除的 TNBC 细胞迁移和侵袭受损。

结论

我们表明，YTHDC1 通过促进 mRNA 的核输出和表达来增强 TGF-β 信号级联，在 TNBC 转移中发挥关键的致癌作用。总体而言，我们的研究表明，YTHDC1 通过增强 TNBC 细胞的存活和 TGF-β 介导的 EMT 来促进 TNBC 进展，通过 SMAD3 来促进远处转移的形成，从而为 TNBC 治疗提供了靶向 YTHDC1/mA/SMAD3 轴的治疗潜力。