Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
Int J Mol Sci. 2024 Jan 28;25(3):1630. doi: 10.3390/ijms25031630.
() and () are two long noncoding RNAs upregulated in multiple cancers, marking these RNAs as therapeutic targets. While traditional small-molecule and antisense-based approaches are effective, we report a locked nucleic acid (LNA)-based approach that targets the and triple helices, structures comprised of a U-rich internal stem-loop and an A-rich tract. Two LNA oligonucleotides resembling the A-rich tract (i.e., AGCA) were examined: an LNA (L15) and a phosphorothioate LNA (PS-L15). L15 binds tighter than PS-L15 to the and stem loops, although both L15 and PS-L15 enable RNA•LNA-RNA triple-helix formation. Based on UV thermal denaturation assays, both LNAs selectively stabilize the Hoogsteen interface by 5-13 °C more than the Watson-Crick interface. Furthermore, we show that L15 and PS-L15 displace the A-rich tract from the and stem loop and methyltransferase-like protein 16 (METTL16) from the METTL16- triple-helix complex. Human colorectal carcinoma (HCT116) cells transfected with LNAs have 2-fold less and . This LNA-based approach represents a potential therapeutic strategy for the dual targeting of and .
() 和 () 是在多种癌症中上调的两种长非编码 RNA，这表明这些 RNA 是治疗靶点。虽然传统的小分子和反义药物方法是有效的，但我们报告了一种基于锁核酸 (LNA) 的方法，该方法靶向和三螺旋结构，该结构由富含 U 的内部茎环和富含 A 的区域组成。两种类似于富含 A 的区域 (即 AGCA) 的 LNA 寡核苷酸进行了研究：LNA (L15) 和硫代磷酸酯 LNA (PS-L15)。尽管 L15 和 PS-L15 都能使 RNA•LNA-RNA 三螺旋形成，但 L15 与和茎环的结合比 PS-L15 更紧密。基于 UV 热变性测定，两种 LNA 都选择性地使 Hoogsteen 界面稳定 5-13°C，比 Watson-Crick 界面稳定 5-13°C。此外，我们表明 L15 和 PS-L15 可将富含 A 的区域从和茎环以及甲基转移酶样蛋白 16 (METTL16) 从 METTL16-三螺旋复合物中置换出来。用 LNA 转染的人结肠直肠癌细胞中，和的表达减少了 2 倍。这种基于 LNA 的方法代表了针对和双重靶向的潜在治疗策略。
