Non-coding RNAs that are more than 200 nt are known as long non-coding RNAs (lncRNAs). LncRNAs affect gene expression at the epigenetic, transcriptional, post-transcriptional, translational, and post-translational levels by interacting with mRNA, DNA, proteins, and miRNAs [10], [11], [14]. Long intergenic non-coding RNAs (lincRNAs) are a group of long non-coding RNAs (lncRNAs) that do not have overlap with annotated coding genes [17], [27]. These transcripts share several features with lncRNAs and include more than half of lncRNAs in humans [9], [21]. They have been firstly identified through application of tiling array techniques across genomic sequences, which showed persistent transcriptions from genomic areas having no recognized coding genes [1], [15], [22]. The main feature of lincRNAs that distinguishes them from other lncRNAs is lack of shared sequences with coding loci. Identification of lincRNAs in gene poor areas of the genome may decline the load of evolutionary conservation, thus permitting rapid functional divergence of lincRNA loci [21]. LincRNAs can influence activity of chromatin modification complexes or RNA binding proteins, thus changing gene expressing programs [25]. Most notably, they exhibit distinctive gene signatures between primary tumor samples and metastatic ones [25]. In addition to RNA-dependent activities, lincRNA loci have been suggested to serve as DNA elements, mediating RNA-independent functions [26]. It has been estimated that the number of lincRNAs in human genome exceeds 15,000 [6]. Recently, several lincRNAs have been identified that contribute in the pathogenesis of human disorders, particularly cancers through acting as either tumor suppressors or oncogenes [5], [12].

Long intergenic non-protein coding RNA 324 (LINC00324) is an example of this group of lncRNAs whose roles in the carcinogenesis is being elucidated. This lncRNA is encoded by a gene located on 17p13.1. Being alternatively named as Chromosome 17 Open Reading Frame 44 (HGNC), Non-Protein Coding RNA 324 (HGNC), NONHSAG020759.2 (NONCODE), HSALNG0114408 (LncBook) and HSALNG0114404 (LncBook), it has three exons and 2100 bp. Currently, no splice variant has been identified for LINC00324. Recent studies have assessed expression of LINC00324 in different cancers revealing a possible oncogenic role for it in most of assessed tissues. However, in some tissues, it has the opposite effect. The current review summarizes the evidence regarding the impact of lINC00324 in the carcinogenic processes.