Myc/Max dependent intronic long antisense noncoding RNA, EVA1A-AS, suppresses the expression of Myc/Max dependent anti-proliferating gene EVA1A in a U2 dependent manner

Sci Rep. 2019 Nov 21;9(1):17319. doi: 10.1038/s41598-019-53944-2.

Abstract

The Myc gene has been implicated in the pathogenesis of most types of human cancerous tumors. Myc/Max activates large numbers of pro-tumor genes; however it also induces anti-proliferation genes. When anti-proliferation genes are activated by Myc, cancer cells can only survive if they are downregulated. Hepatocellular carcinoma (HCC) specific intronic long noncoding antisense (lnc-AS) RNA, the EVA1A-AS gene, is located within the second intron (I2) of the EVA1A gene (EVA-1 homolog A) that encodes an anti-proliferation factor. Indeed, EVA1A, but not EVA1A-AS, is expressed in normal liver. Depletion of EVA1A-AS suppressed cell proliferation of HepG2 cells by upregulation of EVA1A. Overexpression of EVA1A caused cell death at the G2/M phase via microtubule catastrophe. Furthermore, suppressed EVA1A expression levels are negatively correlated with differentiation grade in 365 primary HCCs, while EVA1A-AS expression levels are positively correlated with patient survival. Notably, both EVA1A and EVA1A-AS were activated by the Myc/Max complex. Eva1A-AS is transcribed in the opposite direction near the 3'splice site of EVA1A I2. The second intron did not splice out in a U2 dependent manner and EVA1A mRNA is not exported. Thus, the Myc/Max dependent anti-proliferating gene, EVA1A, is controlled by Myc/Max dependent anti-sense noncoding RNA for HCC survival.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / genetics
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / metabolism
  • Carcinoma, Hepatocellular / genetics*
  • Carcinoma, Hepatocellular / mortality
  • Carcinoma, Hepatocellular / pathology
  • Cell Proliferation / genetics
  • Datasets as Topic
  • Gene Expression Regulation, Neoplastic
  • Hep G2 Cells
  • Humans
  • Introns / genetics
  • Liver / pathology
  • Liver Neoplasms / genetics*
  • Liver Neoplasms / mortality
  • Liver Neoplasms / pathology
  • Membrane Proteins / genetics*
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism
  • RNA, Long Noncoding / genetics
  • RNA, Long Noncoding / metabolism*
  • RNA, Small Interfering / metabolism
  • RNA, Small Nuclear / metabolism*
  • RNA-Seq
  • Up-Regulation

Substances

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • EVA1A protein, human
  • MAX protein, human
  • MYC protein, human
  • Membrane Proteins
  • Proto-Oncogene Proteins c-myc
  • RNA, Long Noncoding
  • RNA, Small Interfering
  • RNA, Small Nuclear
  • U2 small nuclear RNA