Long noncoding RNA HULC promotes colorectal carcinoma progression through epigenetically repressing NKD2 expression

Gene. 2016 Oct 30;592(1):172-178. doi: 10.1016/j.gene.2016.08.002. Epub 2016 Aug 3.

Abstract

Recently, long noncoding RNAs (lncRNAs) have been emerged as crucial regulators of human diseases and prognostic markers in numerous of cancers, including colorectal carcinoma (CRC). Here, we identified an oncogenetic lncRNA HULC, which may promote colorectal tumorigenesis. HULC has been found to be up-regulated and acts as oncogene in gastric cancer and hepatocellular carcinoma, but its expression pattern, biological function and underlying mechanism in CRC is still undetermined. Here, we reported that HULC expression is also over-expressed in CRC, and its increased level is associated with poor prognosis and shorter survival. Knockdown of HULC impaired CRC cells proliferation, migration and invasion, and facilitated cell apoptosis in vitro, and inhibited tumorigenicity of CRC cells in vivo. Mechanistically, RNA immunoprecipitation (RIP) and RNA pull-down experiment demonstrated that HULC could simultaneously interact with EZH2 to repress underlying targets NKD2 transcription. In addition, rescue experiments determined that HULC oncogenic function is partly dependent on repressing NKD2. Taken together, our findings expound how HULC over-expression endows an oncogenic function in CRC.

Keywords: Apoptosis; Colorectal carcinoma (CRC); Long noncoding RNA HULC; NKD2; Proliferation.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Apoptosis
  • Calcium-Binding Proteins
  • Carcinoma / genetics*
  • Carcinoma / metabolism
  • Carcinoma / pathology
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism
  • Colorectal Neoplasms / genetics*
  • Colorectal Neoplasms / metabolism
  • Colorectal Neoplasms / pathology
  • Enhancer of Zeste Homolog 2 Protein / metabolism
  • Epigenesis, Genetic*
  • HCT116 Cells
  • HT29 Cells
  • Humans
  • Neoplasm Invasiveness
  • Protein Binding
  • RNA, Long Noncoding / genetics*

Substances

  • Adaptor Proteins, Signal Transducing
  • Calcium-Binding Proteins
  • Carrier Proteins
  • HULC long non-coding RNA, human
  • NKD2 protein, human
  • RNA, Long Noncoding
  • EZH2 protein, human
  • Enhancer of Zeste Homolog 2 Protein