Rearrangement of the MLL gene and a region proximal to the RARalpha gene in a case of acute myelocytic leukemia M5 with a t(11;17)(q23;q21).
A case of acute myelocytic leukemia (AML) M5 subtype (French-American-British classification), in a 13-year-old girl showed the abnormal karyotype 46,XX,t(11;17)(q23;q21) in all bone marrow cells analyzed. Rearrangements involving 11q23 are frequent in cases of AML M5 and often involve the MLL gene. Nevertheless, t(11;17)(q23;q21) is very rare in this type of leukemia. In acute promyelocytic leukemia, the RARalpha gene, located at 17q21, is involved in almost all cases. Fluorescence in situ hybridization studies revealed a deletion of the C-terminal part of the MLL gene and a translocation of the RARalpha gene on the derivative chromosome 11, proximal to the remaining part of the MLL gene. However, hybridization with the LSI RARA dual color break-apart rearrangement probe showed that the RARalpha gene was not rearranged in this translocation. This is the first study reporting a t(11;17)(q23;q21) with a deletion distal to MLL gene exon 6 in a case of AML M5. Furthermore, this is the second study that strongly suggests the implication of a gene proximal and close to the RARalpha locus in a case of AML M5. According to these results, the discovery of new fusion partner genes of MLL and the precise characterization of t(11;17) will be important for the understanding of neoplastic cell differentiation in AML M5.
Dubé
Sophie
S
Département de pathologie et de biologie cellulaire, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada.
Fetni
Raouf
R
Hazourli
Sawcène
S
Champagne
Martin
M
Lemieux
Nicole
N
D000293:Adolescent; D002880:Chromosomes, Human, Pair 11; D002886:Chromosomes, Human, Pair 17; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D015321:Gene Rearrangement; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D007621:Karyotyping; D007948:Leukemia, Monocytic, Acute / Q000235:genetics*; D051788:Myeloid-Lymphoid Leukemia Protein; D011519:Proto-Oncogenes; D018168:Receptors, Retinoic Acid / Q000235:genetics*; D014157:Transcription Factors; D014178:Translocation, Genetic
D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D018168:Receptors, Retinoic Acid; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase