High EVI1 levels predict adverse outcome in acute myeloid leukemia: prevalence of EVI1 overexpression and chromosome 3q26 abnormalities underestimated.
Inappropriate expression of EVI1 (ecotropic virus integration-1), in particular splice form EVI1-1D, through chromosome 3q26 lesions or other mechanisms has been implicated in the development of high-risk acute myeloid leukemia (AML). To validate the clinical relevance of EVI1-1D, as well as of the other EVI1 splice forms and the related MDS1/EVI1 (ME) gene, real-time quantitative polymerase chain reaction was performed in 534 untreated adults with de novo AML. EVI1-1D was highly expressed in 6% of cases (n = 32), whereas 7.8% were EVI1(+) (n = 41) when all splice variants were taken into account. High EVI1 predicted a distinctly worse event-free survival (HR = 1.9; P = .002) and disease-free survival (HR = 2.1, P = .006) following multivariate analysis. Importantly, we distinguished a subset of EVI1(+) cases that lacked expression of ME (EVI1(+)ME(-); n = 17) from cases that were ME(+) (EVI1(+)ME(+); n = 24). The atypical EVI1(+)ME(-) expression pattern exhibited cytogenetically detectable chromosomal 3q26 breakpoints in 8 cases. Fluorescence in situ hybridization revealed 7 more EVI1(+)ME(-) cases that carried cryptic 3q26 breakpoints, which were not found in the EVI1(+)ME(+) group. EVI1(+)ME(-) expression predicts an extremely poor prognosis distinguishable from the general EVI1(+) AML patients (overall survival [OS]: P < .001 and event-free survival [EFS]: P = .002). We argue that EVI1/ME quantitative expression analysis should be implemented in the molecular diagnostic procedures of AML.
Lugthart
Sanne
S
Department of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands.
van Drunen
Ellen
E
van Norden
Yvette
Y
van Hoven
Antoinette
A
Erpelinck
Claudia A J
CA
Valk
Peter J M
PJ
Beverloo
H Berna
HB
Löwenberg
Bob
B
Delwel
Ruud
R
D000328:Adult; D000368:Aged; D017398:Alternative Splicing / Q000235:genetics; D002869:Chromosome Aberrations; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics*; D015331:Cohort Studies; D020732:Cytogenetic Analysis; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015973:Gene Expression Regulation, Leukemic; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000235:genetics / Q000473:pathology*; D000074008:MDS1 and EVI1 Complex Locus Protein; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D011519:Proto-Oncogenes / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D016019:Survival Analysis; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D016896:Treatment Outcome
D004268:DNA-Binding Proteins; D000074008:MDS1 and EVI1 Complex Locus Protein; C063575:MECOM protein, human; D020033:Protein Isoforms; D012333:RNA, Messenger; D014157:Transcription Factors