A MIR17HG-derived Long Noncoding RNA Provides an Essential Chromatin Scaffold for Protein Interaction and Myeloma Growth

Abstract

<jats:p>Long noncoding RNAs (lncRNA) can drive tumorigenesis and are susceptible to therapeutic intervention. Here, we used a large-scale CRISPR interference viability screen to interrogate cell growth dependency to lncRNA genes in multiple myeloma (MM), and identified a prominent role for the miR-17-92 cluster host gene (MIR17HG). We show that a MIR17HG-derived lncRNA, named lnc-17-92, is the main mediator of cell growth dependency acting in a microRNA- and DROSHA- independent manner. Lnc-17-92 provides a chromatin scaffold for the functional interaction between c-MYC and WDR82, thus promoting the expression of ACACA, which encodes the rate-limiting enzyme of de novo lipogenesis acetyl-coA carboxylase 1 (ACC1). Targeting MIR17HG pre-RNA with clinically applicable antisense molecules disrupts the transcriptional and functional activities of lnc-17-92, causing potent anti-tumor effects both in vitro and in vivo in three pre-clinical animal models, including a clinically relevant PDX-NSG mouse model. This study establishes a novel oncogenic function of MIR17HG and provides potent inhibitors for translation to clinical trials.</jats:p>