Exome sequencing of pleuropulmonary blastoma reveals frequent biallelic loss of TP53 and two hits in DICER1 resulting in retention of 5p-derived miRNA hairpin loop sequences

Oncogene. 2014 Nov 6;33(45):5295-302. doi: 10.1038/onc.2014.150. Epub 2014 Jun 9.

Abstract

Pleuropulmonary blastoma is a rare childhood malignancy of lung mesenchymal cells that can remain dormant as epithelial cysts or progress to high-grade sarcoma. Predisposing germline loss-of-function DICER1 variants have been described. We sought to uncover additional contributors through whole exome sequencing of 15 tumor/normal pairs, followed by targeted resequencing, miRNA analysis and immunohistochemical analysis of additional tumors. In addition to frequent biallelic loss of TP53 and mutations of NRAS or BRAF in some cases, each case had compound disruption of DICER1: a germline (12 cases) or somatic (3 cases) loss-of-function variant plus a somatic missense mutation in the RNase IIIb domain. 5p-Derived microRNA (miRNA) transcripts retained abnormal precursor miRNA loop sequences normally removed by DICER1. This work both defines a genetic interaction landscape with DICER1 mutation and provides evidence for alteration in miRNA transcripts as a consequence of DICER1 disruption in cancer.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Base Sequence
  • Chromosomes, Human, Pair 5 / genetics
  • DEAD-box RNA Helicases / genetics*
  • DEAD-box RNA Helicases / metabolism
  • DNA Copy Number Variations
  • Exome / genetics
  • Female
  • GTP Phosphohydrolases / genetics
  • GTP Phosphohydrolases / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Immunohistochemistry
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / metabolism
  • Male
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • MicroRNAs / chemistry
  • MicroRNAs / genetics*
  • Mutation*
  • Nucleic Acid Conformation
  • Oligonucleotide Array Sequence Analysis
  • Proto-Oncogene Proteins B-raf / genetics
  • Proto-Oncogene Proteins B-raf / metabolism
  • Pulmonary Blastoma / genetics*
  • Pulmonary Blastoma / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Ribonuclease III / genetics*
  • Ribonuclease III / metabolism
  • Sequence Analysis, DNA / methods
  • Tumor Suppressor Protein p53 / genetics*
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • Membrane Proteins
  • MicroRNAs
  • Tumor Suppressor Protein p53
  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf
  • DICER1 protein, human
  • Ribonuclease III
  • GTP Phosphohydrolases
  • NRAS protein, human
  • DEAD-box RNA Helicases

Supplementary concepts

  • Pleuropulmonary blastoma