Long noncoding RNA MALAT1 may be a prognostic biomarker in IDH1/2 wild-type primary glioblastomas

Bosn J Basic Med Sci. 2020 Feb 5;20(1):63-69. doi: 10.17305/bjbms.2019.4297.

Abstract

Primary glioblastoma (GB) is the most aggressive type of brain tumors. While mutations in isocitrate dehydrogenase (IDH) genes are frequent in secondary GBs and correlate with a better prognosis, most primary GBs are IDH wild-type. Recent studies have shown that the long noncoding RNA metastasis associated lung adenocarcinoma transcript-1 (MALAT1) is associated with aggressive tumor phenotypes in different cancers. Our aim was to clarify the prognostic significance of MALAT1 in IDH1/2 wild-type primary GB tumors. We analyzed IDH1/2 mutation status in 75 patients with primary GB by DNA sequencing. The expression of MALAT1 was detected in the 75 primary GB tissues and 5 normal brain tissues using reverse transcription quantitative PCR (RT-qPCR). The associations between MALAT1 expression, IDH1/2 mutation status, and clinicopathological variables of patients were determined. IDH1 (R132H) mutation was observed in 5/75 primary GBs. IDH2 (R172H) mutation was not detected in any of our cases. MALAT1 expression was significantly upregulated in primary GB vs. normal brain tissues (p = 0.025). Increased MALAT1 expression in IDH1/2 wild-type primary GBs correlated with patient age and tumor localization (p = 0.032 and p = 0.025, respectively). A multivariate analysis showed that high MALAT1 expression was an unfavorable prognostic factor for overall survival (p = 0.034) in IDH1/2 wild-type primary GBs. High MALAT1 expression may have a prognostic role in primary GBs independent of IDH mutations.

MeSH terms

  • Adult
  • Aged
  • Biomarkers, Tumor / metabolism
  • Brain Neoplasms / genetics*
  • Brain Neoplasms / metabolism
  • Female
  • Glioblastoma / genetics*
  • Glioblastoma / metabolism
  • Humans
  • Isocitrate Dehydrogenase / genetics*
  • Male
  • Middle Aged
  • Mutation / genetics*
  • RNA, Long Noncoding / genetics*
  • RNA, Long Noncoding / metabolism
  • RNA, Messenger / metabolism
  • Retrospective Studies
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Biomarkers, Tumor
  • MALAT1 long non-coding RNA, human
  • RNA, Long Noncoding
  • RNA, Messenger
  • IDH2, human
  • Isocitrate Dehydrogenase
  • IDH1 protein, human