Du, Z. et al. Nat. Commun. 7, 10982 (2016).

Of the approximately 10,000 long noncoding (lnc) RNAs encoded in the human genome, the functions of only a few have been characterized. Some lncRNAs have been shown to harbor binding sites for microRNAs and thus act as their repressors, by preventing microRNAs from binding their targets on protein-coding genes (PCGs). To learn about the regulatory networks formed by these so-called sponge lncRNAs, Du et al. used gene expression data on lncRNAs and PCGs with shared microRNA binding domains. Their network consisted of 52 lncRNAs and 17 PCGs in prostate cancer cells. lncRNAs that effectively repressed microRNAs resided in the cytoplasm, and some, such as the lncRNA that binds a microRNA targeting PTEN, were shown to have tumor-suppressive effects.