Castanotto Daniela, Zhang Xiaowei, Rüger Jacqueline, Alluin Jessica, Sharma Ritin, Pirrotte Patrick, Joenson Lars, Ioannou Silvia, Nelson Michael S, Vikeså Jonas, Hansen Bo Rode, Koch Troels, Jensen Mads Aaboe, Rossi John J, Stein Cy A
Department of Medical Oncology, City of Hope, 1500 East Duarte Road, Duarte, CA 91010, USA.
Department of Molecular and Cellular Biology, City of Hope, 1500 East Duarte Road, Duarte, CA 91010, USA.
Mol Ther Nucleic Acids. 2020 Oct 27;23:63-75. doi: 10.1016/j.omtn.2020.10.032. eCollection 2021 Mar 5.
The androgen receptor (AR) plays a critical role in the development of prostate cancer (PCa) through the activation of androgen-induced cellular proliferation genes. Thus, blocking AR-mediated transcriptional activation is expected to inhibit the growth and spread of PCa. Using tailor-made splice-switching locked nucleic acid (LNA) oligonucleotides (SSOs), we successfully redirected splicing of the AR precursor (pre-)mRNA and destabilized the transcripts via the introduction of premature stop codons. Furthermore, the SSOs simultaneously favored production of the AR45 mRNA in lieu of the full-length AR. AR45 is an AR isoform that can attenuate the activity of both full-length and oncogenic forms of AR by binding to their common N-terminal domain (NTD), thereby blocking their transactivation potential. A large screen was subsequently used to identify individual SSOs that could best perform this dual function. The selected SSOs powerfully silence AR expression and modulate the expression of AR-responsive cellular genes. This bi-functional strategy that uses a single therapeutic molecule can be the basis for novel PCa treatments. It might also be customized to other types of therapies that require the silencing of one gene and the simultaneous expression of a different isoform.
雄激素受体（AR）通过激活雄激素诱导的细胞增殖基因，在前列腺癌（PCa）的发展中发挥关键作用。因此，阻断AR介导的转录激活有望抑制PCa的生长和扩散。我们使用特制的剪接转换锁核酸（LNA）寡核苷酸（SSO），成功地重定向了AR前体（pre-）mRNA的剪接，并通过引入提前终止密码子使转录本不稳定。此外，SSO同时促进了AR45 mRNA的产生，以替代全长AR。AR45是一种AR异构体，它可以通过与全长AR和致癌形式AR的共同N端结构域（NTD）结合，来减弱它们的活性，从而阻断它们的反式激活潜能。随后进行了大规模筛选，以鉴定能够最佳执行这种双重功能的单个SSO。所选的SSO能有效沉默AR表达，并调节AR反应性细胞基因的表达。这种使用单一治疗分子的双功能策略可能成为新型PCa治疗方法的基础。它也可能被定制用于其他类型的治疗，这些治疗需要沉默一个基因并同时表达不同的异构体。
