N6-甲基腺苷 (m6A) 修饰失调与乳腺癌发病机制有关。众所周知，实体瘤缺氧会重新编程 m6A 表观转录组，但这一过程如何促进乳腺癌进展的潜在机制仍知之甚少。通过对 m6A-RIP 测序和 RNA 测序数据库的综合分析，我们揭示了一系列在缺氧条件下 m6A 甲基化和表达上调的 mRNA，这些 mRNA 因许多致癌途径（包括 PI3K-Akt 信号传导）而富集。此外，我们确定 mRNA RIPOR3 是 METTL3 介导的 m6A 甲基化响应缺氧的靶标。我们发现 m6A 甲基化稳定 RIPOR3，以 METTL3 催化活性依赖性方式增加其蛋白表达，从而驱动乳腺肿瘤生长和转移。研究发现 RIPOR3 在乳腺癌细胞系和乳腺癌患者的肿瘤组织中过度表达，其中升高的 RIPOR3 与较差的预后相关。从机制上讲，我们表明 RIPOR3 与 EGFR 相互作用，并且对于 PI3K-Akt 通路激活至关重要。总之，我们通过 METTL3 介导的 m6A 甲基化将 RIPOR3 确定为缺氧稳定的致癌驱动因素，从而为乳腺癌提供潜在的治疗靶点。© 2024。作者获得 Springer Nature Limited 的独家许可。

Dysregulated N6-methyladenosine (m6A) modification has been associated with breast cancer pathogenesis. Hypoxia which characterizes solid tumors is known to reprogram the m6A epitranscriptome, but the underlying mechanisms of how this process contributes to breast cancer progression remain poorly understood. Through integrative analyses of m6A-RIP sequencing and RNA sequencing databases, we reveal a cluster of mRNAs with upregulated m6A methylation and expression under hypoxia, that are enriched by many oncogenic pathways, including PI3K-Akt signaling. Furthermore, we identify the mRNA, RIPOR3, as a target of METTL3-mediated m6A methylation in response to hypoxia. We find that m6A methylation stabilizes RIPOR3, increasing its protein expression in a METTL3 catalytic activity-dependent manner, and consequently driving breast tumor growth and metastasis. RIPOR3 is found to be overexpressed in breast cancer cell lines and tumor tissues from breast cancer patients, in whom elevated RIPOR3 is associated with a worse prognosis. Mechanistically, we show that RIPOR3 interacts with EGFR and is essential for the PI3K-Akt pathway activation. In conclusion, we identify RIPOR3 as a hypoxia-stabilized oncogenic driver via METTL3-mediated m6A methylation, thus provide a potential therapeutic target for breast cancer.© 2024. The Author(s), under exclusive licence to Springer Nature Limited.