Expression of phosphorylated signal transducer and activator of transcription 5 is associated with an increased risk of death in acute myeloid leukemia.
BACKGROUND
Constitutive activation of STAT5 (by phosphorylation) has been identified in a number of malignancies, including acute myeloid leukemia (AML).


OBJECTIVE
We investigated whether the level of phosphorylated STAT5 (pSTAT5) expression correlates with clinical outcome in AML.


METHODS
Adult patients with newly diagnosed AML receiving induction chemotherapy and with an available diagnostic bone marrow were evaluated.


RESULTS
Forty-two percent of patients had pSTAT5 expression >0 on immunohistochemical analysis of fixed bone marrow core biopsies. In multivariable analyses, controlling for age, history of antecedent hematologic disorder, cytogenetic risk, and WBC at diagnosis, pSTAT5 expression was significantly associated with an increased risk of death (HR 1.96, 95% CI 1.19-3.23, P = 0.008) and of relapse after achieving complete remission (HR 2.31, 95% CI 1.16-4.63, P = 0.018).


CONCLUSIONS
Validation of pSTAT5's prognostic value requires additional study in a larger group of uniformly treated patients. However, our data suggests that targeting this signaling pathway in AML may improve the outcome of patients.
Hematologic Oncology and Blood Disorders, Cleveland Clinic Taussig Cancer Institute, Cleveland, OH 44195, USA.
Anna
A
Brady
Sarah
S
Gibson
Lisa
L
Rybicki
Eric
E
Hsi
Yogen
Y
Saunthararajah
Mikkael A
MA
Sekeres
Ramon
R
Tiu
Edward
E
Copelan
Matt
M
Kalaycio
Ronald
R
Sobecks
Jennifer
J
Bates
Anjali S
AS
Advani
D006801:Humans; D007150:Immunohistochemistry; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism / Q000401:mortality*; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D012307:Risk Factors; D050799:STAT5 Transcription Factor / Q000378:metabolism*; D051941:fms-Like Tyrosine Kinase 3 / Q000235:genetics
D050799:STAT5 Transcription Factor; C497970:FLT3 protein, human; D051941:fms-Like Tyrosine Kinase 3