Green Darrell, Singh Archana, Tippett Victoria L, Tattersall Luke, Shah Karan M, Siachisumo Chileleko, Ward Nicole J, Thomas Paul, Carter Simon, Jeys Lee, Sumathi Vaiyapuri, McNamara Iain, Elliott David J, Gartland Alison, Dalmay Tamas, Fraser William D
Biomedical Research Centre, Norwich Medical School, University of East Anglia, Norwich, UK.
School of Biological Sciences, University of East Anglia, Norwich, UK.
J Bone Oncol. 2023 Mar 5;39:100474. doi: 10.1016/j.jbo.2023.100474. eCollection 2023 Apr.
Primary bone cancer (PBC) comprises several subtypes each underpinned by distinctive genetic drivers. This driver diversity produces novel morphological features and clinical behaviour that serendipitously makes PBC an excellent metastasis model. Here, we report that some transfer RNA-derived small RNAs termed tRNA fragments (tRFs) perform as a constitutive tumour suppressor mechanism by blunting a potential pro-metastatic protein-RNA interaction. This mechanism is reduced in PBC progression with a gradual loss of tRNAGly cleavage into 5' end tRF-Gly when comparing low-grade, intermediate-grade and high-grade patient tumours. We detected recurrent activation of miR-140 leading to upregulated expression in high-grade patient tumours. Both tRF-Gly and share a sequence motif in their 3' ends that matches the YBX1 recognition site known to stabilise pro-metastatic mRNAs. Investigating some aspects of this interaction network, gain- and loss-of-function experiments using small RNA mimics and antisense LNAs, respectively, showed that ectopic tRF-Gly reduced expression and dispersed 3D micromass architecture . iCLIP sequencing revealed YBX1 physical binding to the 3' UTR of . The interaction between YBX1, tRF-Gly and led to the development of the RUNX2 inhibitor CADD522 as a PBC treatment. CADD522 assessment revealed significant effects on PBC cell behaviour. In xenograft mouse models, CADD522 as a single agent without surgery significantly reduced tumour volume, increased overall and metastasis-free survival and reduced cancer-induced bone disease. Our results provide insight into PBC molecular abnormalities that have led to the identification of new targets and a new therapeutic.
原发性骨癌（PBC）包括几种亚型，每种亚型都有独特的基因驱动因素。这种驱动因素的多样性产生了新的形态特征和临床行为，这意外地使PBC成为一个优秀的转移模型。在这里，我们报道一些称为tRNA片段（tRFs）的转移RNA衍生的小RNA通过减弱潜在的促转移蛋白-RNA相互作用来发挥组成性肿瘤抑制机制。在PBC进展过程中，当比较低级别、中级别和高级别患者肿瘤时，这种机制会随着tRNAGly切割成5'端tRF-Gly的逐渐丧失而降低。我们检测到miR-140在高级别患者肿瘤中反复激活，导致表达上调。tRF-Gly和 在其3'端都有一个序列基序，与已知可稳定促转移mRNA的YBX1识别位点相匹配。研究这个相互作用网络的一些方面，分别使用小RNA模拟物和反义锁核酸进行功能获得和功能丧失实验，结果表明异位tRF-Gly降低了 表达并分散了3D微团结构。iCLIP测序揭示了YBX1与 的3'UTR的物理结合。YBX1、tRF-Gly和 之间的相互作用导致了RUNX2抑制剂CADD522作为PBC治疗药物的开发。CADD522评估显示对PBC细胞行为有显著影响。在异种移植小鼠模型中，CADD522作为单一药物无需手术即可显著减小肿瘤体积，提高总体生存率和无转移生存率，并减少癌症诱导的骨病。我们的结果为PBC分子异常提供了见解，这些异常导致了新靶点和新疗法的发现。
