Prognostic significance of MYCN gene amplification and protein expression in primary brain tumors: Astrocytoma and meningioma

Cancer Biomark. 2017 Jul 4;19(3):341-351. doi: 10.3233/CBM-160546.

Abstract

Background: Astrocytoma and meningioma are the most common primary brain tumors. MYCN as a member of MYC proto-oncogenes has recently appeared as an attractive therapeutic target. Functions of MYCN are critical for growth of nervous system and neural differentiation.

Objective: We examined MYCN amplification and protein expression in astrocytoma and meningioma cases.

Methods: In this study, we used real-time PCR, FISH assay and flowcytometry to analyze DNA amplification and protein expression of MYCN.

Results: Among 30 samples of brain tumor, 14 cases (46.6%) revealed MYCN amplification. High-protein expression of MYCN was also observed in 43.3% of patients. There was a significant correlation between MYCN gene amplification and protein expression (r= 0.523; p= 0.003), interestingly five case showed discrepancy between the gene amplification and protein expression. Although MYCN amplification fails to show correlation with poor prognosis (p= 0.305), protein high-expression of MYCN significantly reduce disease-free survival (p= 0.019).

Conclusions: Our results challenge the concept of the neural specificity of MYCN by demonstrating contribution of MYCN in meningioma. Moreover, this study highlights the importance of research at both level of DNA and protein, to determine the biological functions and medical impacts of MYCN.

Keywords: MYCN; amplification; astrocytoma; expression; meningioma.

MeSH terms

  • Adult
  • Astrocytoma / genetics*
  • Astrocytoma / metabolism
  • Astrocytoma / pathology
  • Brain Neoplasms / genetics*
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology
  • Female
  • Gene Amplification
  • Humans
  • Male
  • Meningioma / genetics*
  • Meningioma / metabolism
  • Meningioma / pathology
  • Middle Aged
  • N-Myc Proto-Oncogene Protein / biosynthesis
  • N-Myc Proto-Oncogene Protein / genetics*
  • Prognosis

Substances

  • MYCN protein, human
  • N-Myc Proto-Oncogene Protein