Metastasis-associated long noncoding RNAs in gastrointestinal cancer: Implications for novel biomarkers and therapeutic targets

Figure 2 Mechanisms of long noncoding RNAs according to the subcellular localization. lncRNAs in nucleus frequently interact with protein complexes (such as PRC2) to modify chromatin structures. LncRNAs can also recruit transcription factors to promote or repress gene transcription, through regulating SR proteins, or form RNA-RNA duplexes with pre-mRNAs. Some lncRNAs (such as H19) are spliced into pri-miRNAs, which contributed to miRNA processing. In cytoplasm, lncRNAs may form specific structures with mRNA and interact with some active elements or repressive elements to modulate mRNA translation. By forming RNA-RNA complementary sites with mRNA or microRNA, lncRNAs can promote or inhibit mRNA stability and serve as “sponges” for miRNAs. lncRNAs: Long noncoding RNAs; PRC2: Polycomb repressive complex2.