High TOP2B/TOP2A expression ratio at diagnosis correlates with favourable outcome for standard chemotherapy in acute myeloid leukaemia
British Journal of Cancer, 05/25/2012
Song JH et al. – Genes with distinct expression profiles such as TOP2B/TOP2A expression ratio at diagnosis can be employed for outcome prediction after the treatment with standard regimens in acute myeloid leukaemia (AML) patients with M2 subtype.Methods
- The mRNA expression of 12 genes closely involved in the actions of cytosine arabinoside and anthracycline was evaluated by real–time reverse transcriptase PCR (RT–PCR), in 54 diagnostic bone marrow specimens of M2–subtype AML.
- Low expression levels of ribonucleotide reductase M2 (RRM2) and high expression levels of topoisomerase 2 beta (TOP2B) were correlated with longer survival in a univariate analysis.
- Another interesting finding is that high ratios of TOP2B/RRM2 and TOP2B/TOP2 alpha (TOP2A) in a combined analysis were also shown to have a prognostic impact for longer survival with improved accuracy.
- Among the four markers, when adjusted for the influence of other clinical factors in multivariate analysis, the TOP2B/TOP2A ratio was significantly correlated with treatment outcomes; patients with high ratios trended toward longer disease–free survival (HR, 0.24; P=0.002) and overall survival (HR, 0.29; P=0.005).