HOX11L2 expression defines a clinical subtype of pediatric T-ALL associated with poor prognosis.
The most frequent oncogenic activation events characterized in childhood T acute lymphoblastic leukemia (T-ALL) result in the transcriptional activation of genes coding for transcription factors. The main genes are TAL1/SCL, a member of the basic region helix-loop-helix gene family, and HOX11L2, a member of the homeobox-containing protein family. To gain insight into the pathogenesis of this type of hematologic malignancy, we analyzed 28 T-ALL samples. SIL-TAL1/SCL fusion was detected in 6 patients; expression of HOX11L2 was observed in 6 patients and of HOX11 in 3 patients. With one exception, these activations did not occur simultaneously in the same patients, and they allowed the subclassification of 50% of the patients. SIL-TAL1 fusion was detected in association with HOX11 expression in one patient and with a t(8;14) (q24;q11) in another. High expression of LYL1, LMO2, or TAL1 was observed mainly in samples negative for HOX11L2 expression. HOX11L1 and HOX11 expression were observed in one instance each, in the absence of detectable chromosomal abnormality of their respective loci, on chromosomes 2 and 10, respectively. HOX11L2 expression was associated with a chromosome 5q abnormality, the location of the HOX11L2 locus in each case tested. Finally, our data show that HOX11L2 expression was a suitable marker for minimal residual disease follow-up and was significantly associated with relapse (P =.02).
Ballerini
Paola
P
Service d'Hématologie Biologique, Hôpital Armand Trousseau, Paris, France. paola.ballerini@trs.ap-hop-paris.fr
Blaise
Annick
A
Busson-Le Coniat
Maryvonne
M
Su
Xin Ying
XY
Zucman-Rossi
Jessica
J
Adam
Mircea
M
van den Akker
Jacqueline
J
Perot
Christine
C
Pellegrino
Beatrice
B
Landman-Parker
Judith
J
Douay
Luc
L
Berger
Roland
R
Bernard
Olivier A
OA
D048868:Adaptor Proteins, Signal Transducing; D000293:Adolescent; D051792:Basic Helix-Loop-Helix Proteins; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics; D020732:Cytogenetic Analysis; D004268:DNA-Binding Proteins / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D060588:LIM Domain Proteins; D015458:Leukemia, T-Cell / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D008297:Male; D008667:Metalloproteins / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism; D018365:Neoplasm, Residual / Q000175:diagnosis / Q000378:metabolism; D015513:Oncogene Proteins / Q000378:metabolism*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D011379:Prognosis; D011518:Proto-Oncogene Proteins; D016019:Survival Analysis; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D014157:Transcription Factors
D048868:Adaptor Proteins, Signal Transducing; D051792:Basic Helix-Loop-Helix Proteins; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D060588:LIM Domain Proteins; D008667:Metalloproteins; D009363:Neoplasm Proteins; D015513:Oncogene Proteins; D011518:Proto-Oncogene Proteins; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D014157:Transcription Factors; C085117:LMO2 protein, human; C086541:LYL1 protein, human; C489494:TLX3 protein, human; C067143:TAL1 protein, human; C071250:TLX1 protein, human