Breast and Thyroid III, Affiliated Zhongshan Hospital of Dalian University, Dalian, China.
J BUON. 2021 Mar-Apr;26(2):444-449.
We aimed to uncover the role of METTL3 in stimulating the stemness and progression of breast cancer (BCa) through mediating N6-methyladenosine (m6A) modification on SOX2 mRNA.
METTL3 levels in 48 paired BCa and adjacent normal ones were examined. Kaplan-Meier method was introduced for assessing the prognostic value of METTL3 in BCa. Regulatory effects of METTL3 on invasive and migratory abilities in MCF-7 cells were evaluated by Transwell assay. Besides, the protein levels of SOX2 and tumor stem cell markers CD133 and CD44 in MCF-7 cells affected by METTL3 were determined by Western blot. In addition, the potential interaction between METTL3 and SOX2 was ascertained through RIP (RNA-Binding Protein Immunoprecipitation) assay. Moreover, the interaction between IGF2BP2 and SOX2 influenced by METTL3 was verified by RIP assay as well.
METTL3 was upregulated in BCa tissues, especially in T3-T4 or those accompanied with lymphatic metastasis. BCa patients expressing a high level of METTL3 suffered worse prognosis. Knockdown of METTL3 downregulated protein levels of SOX2, CD133 and CD44 in MCF-7 cells. Moreover, invasive and migratory abilities were attenuated in BCa cells with METTL3 knockdown. Silencing of IGF2BP2 markedly downregulated SOX2. RIP assay confirmed the binding between METTL3 and SOX2 mRNA, and knockdown of METTL3 decreased the enrichment of SOX2 in anti-IGF2BP2. Interestingly, overexpression of SOX2 partially reversed the regulatory effects of downregulated METTL3 on MCF-7 cells.
METTL3 is upregulated in BCa, and it promotes the stemness and malignant progression of BCa through mediating m6A modification on SOX2 mRNA.
通过介导 SOX2 mRNA 上的 N6-甲基腺苷（m6A）修饰，揭示 METTL3 在刺激乳腺癌（BCa）干性和进展中的作用。
检测 48 对 BCa 和相邻正常组织中的 METTL3 水平。采用 Kaplan-Meier 法评估 METTL3 在 BCa 中的预后价值。通过 Transwell 测定评估 METTL3 对 MCF-7 细胞侵袭和迁移能力的调节作用。此外，通过 Western blot 测定受 METTL3 影响的 MCF-7 细胞中 SOX2 和肿瘤干细胞标志物 CD133 和 CD44 的蛋白水平。此外，通过 RNA 结合蛋白免疫沉淀（RIP）测定确定 METTL3 与 SOX2 之间的潜在相互作用。此外，还通过 RIP 测定验证了 METTL3 对 IGF2BP2 和 SOX2 之间相互作用的影响。
METTL3 在 BCa 组织中上调，尤其是在 T3-T4 或伴有淋巴转移的组织中。表达高水平 METTL3 的 BCa 患者预后较差。METTL3 敲低下调 MCF-7 细胞中 SOX2、CD133 和 CD44 的蛋白水平。此外，METTL3 敲低可减弱 BCa 细胞的侵袭和迁移能力。IGF2BP2 沉默显著下调 SOX2。RIP 测定证实了 METTL3 与 SOX2 mRNA 之间的结合，METTL3 敲低降低了 SOX2 在抗 IGF2BP2 中的富集。有趣的是，SOX2 的过表达部分逆转了下调 METTL3 对 MCF-7 细胞的调节作用。
METTL3 在 BCa 中上调，通过介导 SOX2 mRNA 上的 m6A 修饰，促进 BCa 的干性和恶性进展。
