The long non-coding RNA OTX2-AS1 promotes tumor growth and predicts response to BCL-2 inhibition in medulloblastoma

J Neurooncol. 2023 Nov;165(2):329-342. doi: 10.1007/s11060-023-04508-y. Epub 2023 Nov 17.

Abstract

Purpose: Primary brain tumors are a leading cause of cancer-related death in children, and medulloblastoma is the most common malignant pediatric brain tumor. The current molecular characterization of medulloblastoma is mainly based on protein-coding genes, while little is known about the involvement of long non-coding RNAs (lncRNAs). This study aimed to elucidate the role of the lncRNA OTX2-AS1 in medulloblastoma.

Methods: Analyses of DNA copy number alterations, methylation profiles, and gene expression data were used to characterize molecular alterations of OTX2-AS1 in medulloblastoma tissue samples. In vitro analyses of medulloblastoma cell models and orthotopic in vivo experiments were carried out for functional characterization of OTX2-AS1. High-throughput drug screening was employed to identify pharmacological inhibitors, while proteomics and metabolomics analyses were performed to address potential mechanisms of drug action.

Results: We detected amplification and consecutive overexpression of OTX2 and OTX2-AS1 in a subset of medulloblastomas. In addition, OTX2-AS1 promoter methylation was linked to OTX2-AS1 expression. OTX2-AS1 knockout reduced medulloblastoma cell viability and cell migration in vitro and prolonged survival in the D283 orthotopic medulloblastoma mouse xenograft model. Pharmacological inhibition of BCL-2 suppressed the growth of OTX2-AS1 overexpressing medulloblastoma cells in vitro.

Conclusions: Our study revealed a pro-tumorigenic role of OTX2-AS1 in medulloblastoma and identified BCL-2 inhibition as a potential therapeutic approach to target OTX2-AS1 overexpressing medulloblastoma cells.

Keywords: BCL-2 inhibitor; High-throughput drug screening; LncRNA; Medulloblastoma; OTX2-AS1.

MeSH terms

  • Animals
  • Brain Neoplasms* / pathology
  • Cell Line, Tumor
  • Cell Proliferation
  • Cerebellar Neoplasms* / drug therapy
  • Cerebellar Neoplasms* / genetics
  • Cerebellar Neoplasms* / metabolism
  • Child
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Medulloblastoma* / pathology
  • Mice
  • Otx Transcription Factors / genetics
  • Otx Transcription Factors / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • RNA, Long Noncoding* / genetics

Substances

  • Otx Transcription Factors
  • OTX2 protein, human
  • Proto-Oncogene Proteins c-bcl-2
  • RNA, Long Noncoding
  • BCL2 protein, human