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Updated: May 13, 2026

Reconstruct Human Retinoblastoma In Vitro
06:52

Reconstruct Human Retinoblastoma In Vitro

Published on: October 11, 2022

Characterisation of retinoblastomas without RB1 mutations: genomic, gene expression, and clinical studies

Diane E Rushlow1, Berber M Mol, Jennifer Y Kennett

  • 1Impact Genetics and the Toronto Western Hospital Research Institute, University Health Network, Toronto, ON, Canada.

The Lancet. Oncology
|March 19, 2013
PubMed
Abstract

Insights

MYCN oncogene amplification may initiate retinoblastoma in children with intact RB1 genes. These tumors show distinct features and an early diagnosis age.

Area of Science:

  • Oncology
  • Genetics
  • Ophthalmology

Background:

  • Retinoblastoma, a childhood retinal cancer, is linked to tumor-suppressor genes.
  • RB1 gene mutations initiate retinoblastoma.
  • This study investigates retinoblastoma tumors without RB1 mutations.

Purpose of the Study:

  • To characterize non-familial retinoblastoma tumors with no detectable RB1 mutations.
  • To compare these tumors with those carrying RB1 mutations.

Main Methods:

  • Analyzed 1068 unilateral non-familial retinoblastoma tumors.
  • Compared tumors with no RB1 mutations (RB1(+/+)) to those with both alleles mutated (RB1(-/-)).
  • Assessed genomic copy number, gene expression, protein function, histology, and clinical data.

Main Results:

  • 2.7% of tumors (RB1(+/+)) lacked RB1 mutations.
  • 15 of these RB1(+/+) tumors showed MYCN oncogene amplification (RB1(+/+)MYCN(A)).
  • RB1(+/+)MYCN(A) tumors had functional RB1 protein, fewer genomic changes, distinct histology, and earlier diagnosis (median 4.5 months) compared to RB1(-/-) tumors (median 24 months).

Conclusions:

  • MYCN oncogene amplification may initiate retinoblastoma in the presence of functional RB1 genes.
  • RB1(+/+)MYCN(A) retinoblastomas exhibit unique histological features and genomic profiles.
  • These tumors are associated with a significantly earlier age of diagnosis.

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