Characterization of a reference material for BCR-ABL (M-BCR) mRNA quantitation by real-time amplification assays: towards new standards for gene expression measurements

Leukemia. 2007 Jul;21(7):1481-7. doi: 10.1038/sj.leu.2404716. Epub 2007 May 3.


Monitoring of BCR-ABL transcripts has become established practice in the management of chronic myeloid leukemia. However, nucleic acid amplification techniques are prone to variations which limit the reliability of real-time quantitative PCR (RQ-PCR) for clinical decision making, highlighting the need for standardization of assays and reporting of minimal residual disease (MRD) data. We evaluated a lyophilized preparation of a leukemic cell line (K562) as a potential quality control reagent. This was found to be relatively stable, yielding comparable respective levels of ABL, GUS and BCR-ABL transcripts as determined by RQ-PCR before and after accelerated degradation experiments as well as following 5 years storage at -20 degrees C. Vials of freeze-dried cells were sent at ambient temperature to 22 laboratories on four continents, with RQ-PCR analyses detecting BCR-ABL transcripts at levels comparable to those observed in primary patient samples. Our results suggest that freeze-dried cells can be used as quality control reagents with a range of analytical instrumentations and could enable the development of urgently needed international standards simulating clinically relevant levels of MRD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Freeze Drying
  • Fusion Proteins, bcr-abl
  • Gene Expression Profiling / methods*
  • Gene Expression Profiling / standards*
  • Humans
  • Indicators and Reagents
  • K562 Cells
  • Polymerase Chain Reaction / methods*
  • Polymerase Chain Reaction / standards
  • Protein-Tyrosine Kinases / analysis
  • Protein-Tyrosine Kinases / genetics*
  • Quality Control
  • RNA, Messenger / analysis*
  • Reference Standards


  • Indicators and Reagents
  • RNA, Messenger
  • Protein-Tyrosine Kinases
  • Fusion Proteins, bcr-abl