Figure 2.

Types and Functions of lncRNAs

lncRNAs are either classified on the basis of their genomic location and the direction of transcription (1 and 2, intergenic, if located between two genes; 3 and 4, intronic, if present within the intron of the protein-coding gene; 5 and 6, sense or antisense, if transcribed in same or opposite direction of the complementary protein-coding gene) or functions (7, 8, and 9, cis-acting lncRNAs, regulate genes present nearby the site of their transcription; 10 and 11, trans-acting lncRNAs, regulate genes present nearby the site of their transcription). lncRNAs regulate crosstalk between cancer cells and the surrounding microenvironment cells, including dendritic cells, macrophages, endothelial cells, extracellular components, immune cells, myeloid-derived suppressor cells, and fibroblasts. This regulation modulates various functions in tumor cells as shown in the figure.