Long Non-Coding RNAs in Biliary Tract Cancer—An Up-to-Date Review

Abstract

The term long non-coding RNA (lncRNA) describes non protein-coding transcripts with a length greater than 200 base pairs. The ongoing discovery, characterization and functional categorization of lncRNAs has led to a better understanding of the involvement of lncRNAs in diverse biological and pathological processes including cancer. Aberrant expression of specific lncRNA species was demonstrated in various cancer types and associated with unfavorable clinical characteristics. Recent studies suggest that lncRNAs are also involved in the development and progression of biliary tract cancer, a rare disease with high mortality and limited therapeutic options. In this review, we summarize current findings regarding the manifold roles of lncRNAs in biliary tract cancer and give an overview of the clinical and molecular consequences of aberrant lncRNA expression as well as of underlying regulatory functions of selected lncRNA species in the context of biliary tract cancer.

Long Non-Coding RNA-PAICC Promotes the Tumorigenesis of Human Intrahepatic Cholangiocarcinoma by Increasing YAP1 Transcription

“…Although these studies have revealed important findings, they also have limitations. First, we still lack a comprehensive understanding of the regulation of a single lncRNA because the mechanism of ceRNA is only one of its many modes of action ( 11 , 34 ). Most tumors occur due to the cumulative mutation of multiple genes and complex processes involving many signal transduction pathways ( 35 , 36 ).…”

Abnormal methylation mediated upregulation of LINC00857 boosts malignant progression of lung adenocarcinoma by modulating the miR‐486‐5p/NEK2 axis

“…LncRNAs are non‐coding RNAs without open reading frame (ORF) and are usually spliced and polyadenylated 10 . Different subtypes of lncRNAs participate in modulating protein‐coding genes, but the specific molecular mechanisms are varied 11–13 . Among the regulatory mechanisms, competitive endogenous RNA (ceRNA) mechanism has attracted widespread attention.…”

“… 10 Different subtypes of lncRNAs participate in modulating protein‐coding genes, but the specific molecular mechanisms are varied. 11 , 12 , 13 Among the regulatory mechanisms, competitive endogenous RNA (ceRNA) mechanism has attracted widespread attention. lncRNA and miRNA might be a key in regulating of gene expression.…”

Role of lncRNAs in the Development of an Aggressive Phenotype in Gallbladder Cancer

“…These transcripts act by epigenetically regulating the gene expression at post-transcriptional, transcriptional, translational and post-translational levels by forming structures of RNA:RNA, RNA:DNA, and RNA:Protein that allow them to participate in different cellular processes [ 5 , 6 ]. The expression of lncRNAs has been associated with different types of cancers by inducing the acquisition of more aggressive characteristics, such as higher tumorigenic capacity, higher metastatic capacity, induction of epithelial-mesenchymal-transition (EMT) features, drug resistance, and stem-like phenotype, all of them directly related to poor prognosis in cancer patients [ 7 , 8 , 9 , 10 ]. These characteristics are frequently observed in different cancers such as breast, lung, colorectal, and gallbladder cancer [ 3 , 11 ].…”