PO.TB08.01 · 肿瘤生物学
RNA修饰通过ADAM23依赖性通路调控铂类敏感性
RNA modification control of platinum sensitivity via ADAM23-dependent pathway
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
N6-甲基腺苷（m6A）是参与RNA转录后调控的最常见修饰，影响稳定性、剪接和翻译。m6A修饰由甲基转移酶（"writers"）和去甲基化酶（"erasers"）调控。甲基转移酶样3（METTL3）是m6A writer复合物之一，通过将甲基转移至腺苷的N6位来催化m6A修饰。METTL3已被证明通过调节m6A分布和促进致癌转录本的翻译参与肿瘤发生。克服卵巢癌中的铂类耐药是一项重大临床挑战；因此，我们假设METTL3介导的m6A甲基化通过改变细胞对铂类药物的反应而促成耐药。我们使用RT-qPCR和蛋白质印迹评估顺铂处理后的m6A和METTL3表达。为评估其功能作用，我们在METTL3过表达或敲低的卵巢癌细胞系中测定了顺铂的IC50。此外，利用METTL3抑制剂STM2457在体外和体内研究METTL3在卵巢癌中的作用。顺铂处理上调了m6A和METTL3水平。METTL3过表达增强了铂类耐药。相反，METTL3敲低或STM2457处理使细胞对顺铂敏感。RNA-seq分析确定ADAM23为METTL3的下游靶标。ADAM23是ADAM（解整合素与金属蛋白酶）家族的成员，参与细胞黏附和细胞外基质相互作用。该蛋白酶在多种肿瘤中被沉默，包括乳腺癌、胃癌、胰腺癌和胶质瘤。在卵巢癌细胞系中，ADAM23表达与METTL3水平呈负相关，在METTL3过表达时表达降低，在METTL3敲低后表达增加。值得注意的是，顺铂处理通过METTL3上调导致ADAM23表达降低。使用SRAMP进行的进一步分析在人ADAM23 mRNA上确定了几个极高置信度的m6A修饰位点。这些发现表明，METTL3介导的m6A修饰通过调控ADAM23，可能代表卵巢癌中一个新的治疗靶点。
查看英文原文 English abstract
N6-methyladenosine (m6A) is the most common modification involved in post-transcriptional regulation of RNA, affecting stability, splicing, and translation. M⁶A modifications are regulated by methyltransferases (“writers”) and demethylases (“erasers”). Methyltransferase-like 3 (METTL3) is one of the m⁶A writer complexes, catalyzing the m6A modification by transferring a methyl group to the N6 position of adenosine. METTL3 has been implicated in tumor development by modulating m⁶A distribution and promoting the translation of oncogenic transcripts. Overcoming platinum resistance in ovarian cancer is a significant clinical challenge; therefore, we hypothesized that METTL3-mediated m⁶A methylation contributes to resistance by altering cellular response to platinum drugs. We assessed m⁶A and METTL3 expression after cisplatin treatment using RT-qPCR and western blotting. To evaluate their functional role, we measured the IC₅₀ of cisplatin in ovarian cancer cell lines with METTL3 overexpression or knockdown. Additionally, the METTL3 inhibitor STM2457 was utilized to investigate the role of METTL3 in ovarian cancer, both in vitro and in vivo. Cisplatin treatment upregulated m⁶A and METTL3 levels. METTL3 overexpression enhanced platinum resistance. Conversely, METTL3 knockdown or STM2457 treatment sensitized cells to cisplatin. RNA-seq analysis identified ADAM23 as a downstream target of METTL3. ADAM23 is a member of the ADAM (a disintegrin and metalloprotease) family involved in cell adhesion and extracellular matrix interactions. The protease is silenced in various tumors, including breast, gastric, pancreatic cancers, and gliomas. In ovarian cancer cell lines, ADAM23 expression was inversely correlated with METTL3 levels, showing decreased expression upon METTL3 overexpression and increased expression following METTL3 knockdown. Notably, cisplatin treatment led to reduced ADAM23 expression through METTL3 upregulation. Further analysis using SRAMP identified several very high confidence m6A modification sites on ADAM23 mRNA in human. These findings suggest that METTL3-mediated m⁶A modifications, through regulation of ADAM23, may represent a novel therapeutic target in ovarian cancer.
利益披露 Disclosure
H. Huang, None..
U. Kim, None..
J. li, None.