Long non-coding RNAs: a rising biotarget in colorectal cancer

Abstract

Colorectal cancer (CRC) is a common gastrointestinal cancer, with a high incidence and high mortality. Long non-coding RNAs (lncRNAs) are involved in the development, invasion and metastasis, early diagnosis, prognosis, the chemoresistance and radioresistance of CRC through interference with mRNA activity, directly combining with proteins to regulate their activity or alter their localization, influencing downstream gene expression by inhibiting RNA polymerase and regulating gene expression as competing endogenous RNAs. Recent progress in next generation sequencing and transcriptome analysis has revealed that tissue and cancer-type specific lncRNAs could be useful prognostic markers. Here, the CRC-associated lncRNAs from recent studies until October 2016 are reviewed and multiple studies that have confirmed CRC-associated lncRNAs are summarized. This review may be helpful in understanding the overall relationships between the lncRNAs involved in CRC.

Keywords: colorectal cancer; epithelial-mesenchymal transition; invasion; long non-coding RNAs.

Figure 1. The CRC-associated lncRNAs which interact with miRNAs

The blue oval represents normal; the orange ovals represent lncRNAs involved in the interaction with miRNAs; the red rectangles represent miRNAs. FER1L4, CTNNAP1, CASC2, uc002kmd.1, and lnc34a interact with miRNAs to contribute to the pathogenesis of CRC. H19 and CCAT2 are involved in the metastasis and proliferation of CRC via multiple mechanisms including functioning as ceRNAs and through the WNT signaling pathway. Moreover, H19 also promotes tumor growth by recruiting and binding to eIF4A3. The UCA1-miR-204-5p-CREB1/BCL2/RAB22A regulatory network plays an important role in chemoresistance in CRC. lnc00152 acting as a ceRNA of miR-193a-3p increases the levels of ERBB4, contributing to oxaliplatin chemosensitivity in colon cancer.