Analysis of concerted expression of angiogenic growth factors in acute myeloid leukemia: expression of angiopoietin-2 represents an independent prognostic factor for overall survival.
OBJECTIVE
Bone marrow neoangiogenesis plays an important pathogenetic and possible prognostic role in acute myeloid leukemia (AML). Members of the vascular endothelial growth factor (VEGF) and angiopoietin family represent the most specific inducers of angiogenesis secreted by AML blasts. We therefore correlated expression of angiogenic factors with clinical variables.


METHODS
We investigated the expression of VEGF-A, VEGF-C, angiopoietin-1 (Ang1), angiopoietin-2 (Ang2), and the receptor Tie2 by quantitative polymerase chain reaction in a cohort of 90 patients younger than 61 years with de novo AML entered into the German AML Süddeutsche Hämoblastose Gruppe Hannover 95 trial. Uni- and multivariate analyses were performed using clinical and gene expression variables.


RESULTS
Univariate analysis of overall survival indicated the following variables as prognostic factors: good response on a day-15 bone marrow examination after initiation of induction chemotherapy, karyotype, and high Ang2 expression. In multivariate analysis, only bad response and log Ang2 expression remained of statistical significance, with a hazard ratio of 3.51 (95% CI, 1.91 to 6.47) and 0.75 (95% CI, 0.61 to 0.91), respectively. Subgroup analysis suggested that the prognostic impact of Ang2 expression was especially evident in cohorts with low VEGF-C and Ang1 mRNA levels.


CONCLUSIONS
These results show that expression of Ang2 represents an independent prognostic factor in AML. Additional research into interactions of angiogenic cytokines in the pathogenesis of bone marrow angiogenesis in AML is warranted.
Loges
Sonja
S
Medizinische Klinik II, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Heil
Gerhard
G
Bruweleit
Melanie
M
Schoder
Volker
V
Butzal
Martin
M
Fischer
Uta
U
Gehling
Ursula M
UM
Schuch
Gunter
G
Hossfeld
Dieter K
DK
Fiedler
Walter
W
D000208:Acute Disease; D042683:Angiopoietin-1 / Q000378:metabolism; D042702:Angiopoietin-2 / Q000378:metabolism*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007951:Leukemia, Myeloid / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic; D016133:Polymerase Chain Reaction; D011379:Prognosis; D042787:Receptor, TIE-2 / Q000378:metabolism; D016019:Survival Analysis; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D042582:Vascular Endothelial Growth Factor C / Q000378:metabolism; D042442:Vascular Endothelial Growth Factors / Q000378:metabolism*
D042683:Angiopoietin-1; D042702:Angiopoietin-2; D042461:Vascular Endothelial Growth Factor A; D042582:Vascular Endothelial Growth Factor C; D042442:Vascular Endothelial Growth Factors; D042787:Receptor, TIE-2