Expression of BCR-ABL, E2A-PBX1, and MLL-AF4 fusion transcripts in newly diagnosed children with acute lymphoblastic leukemia: a Children's Cancer Group initiative.
We used reverse transcriptase polymerase chain reaction (RT-PCR) assays to examine primary leukemic cells in on-study diagnostic bone marrow specimens from 642 children with newly diagnosed acute lymphoblastic leukemia (ALL) for the expression of MLL-AF4, E2A-PBX1, and BCR-ABL fusion transcripts. All PCR assays were performed centrally in the Children's Cancer Group ALL Biology Reference Laboratory. MLL-AF4 transcript was found in only 0.7% of the study population which excluded infants. E2A-PBX1 transcript was found in 2.5% of the study population and 3.3% of B-precursor cases. Expression was associated with massive hepatomegaly. BCR-ABL transcript was found in 2.3% of cases and correlated with older age, induction failure, and inferior event-free survival (EFS). RT-PCR assays allow rapid identification of patients with MLL-AF4 and BCR-ABL positive ALL. These patients have a poor outcome with contemporary therapy and rapid identification facilitates timely allocation to innovative treatment programs.
Gaynon
P S
PS
University of Wisconsin, Madison, USA.
Crotty
M L
ML
Sather
H N
HN
Bostrom
B C
BC
Nachman
J B
JB
Steinherz
P G
PG
Heerema
N A
NA
Sarquis
M
M
Tuel-Ahlgren
L
L
Uckun
F M
FM
D002648:Child; D018572:Disease-Free Survival; D005260:Female; D016044:Fusion Proteins, bcr-abl / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D008297:Male; D015513:Oncogene Proteins / Q000235:genetics*; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000401:mortality; D012333:RNA, Messenger / Q000096:biosynthesis*; D014158:Transcription, Genetic
D018398:Homeodomain Proteins; D015513:Oncogene Proteins; D015514:Oncogene Proteins, Fusion; D012333:RNA, Messenger; C089847:E2A-Pbx1 fusion protein; D016044:Fusion Proteins, bcr-abl