We used karyotyping, fluorescence in situ hybridization (FISH), Southern blotting, and RT-PCR in order to analyze prospectively 77 infants (less than 1 year of age) with acute lymphoblastic leukemia for the occurrence of 11q23/MLL rearrangements and/or other cytogenetic abnormalities.
We report a case of secondary acute myelogenous leukemia (AML) with 11q23 cytogenetic abnormality and mixed lymphoid leukemia (MLL) gene expression in a patient treated with Y90 labeled anti-CD20 antibody (Zevalin).
We have identified a new mixed lineage leukemia (MLL) gene fusion partner in a patient with treatment-related acute myeloid leukemia (AML) presenting a t(2;11)(q37;q23) as the only cytogenetic abnormality.
We conclude that molecular rearrangement of ALL-1 often can be detected in de novo AML, despite the absence of cytogenetic abnormalities involving 11q23.
Using a comprehensive genomic profiling, we were able to identify recurrent chromosomal aberrations associated with MS including a rare KMT2A-ELL fusion, losses of chromosomes 1p, 9, 10, 15, 18, and gain of chromosome 1q and mutations in FLT3 and PTPN11, and achived the final diagnosis of a de novo MS.
The partial tandem duplication of the ALL1 (MLL) gene is found in patients with AML and trisomy 11 as a sole cytogenetic abnormality and in 11% of patients with AML and normal cytogenetics.
The most common chromosomal abnormality of infant acute lymphoblastic leukemia (ALL) is the t(4;11)(q21;q23) that gives rise to the MLL/AF4 fusion gene.
Specific subsets of MPAL are defined by chromosomal anomalies such as the t(9;22) Philadelphia chromosome BCR-ABL1 or involvement of the MLL gene on chromosome 11q23.
Southern blot analysis indicated that the MLL rearrangement was involved in the chromosomal abnormality. cDNA panhandle polymerase chain reaction identified the fusion transcript, in which MLL exon 6 was fused in-frame with CBL exon 8.
Southern blot analysis indicated that a rearrangement of the MLL gene was involved in the chromosomal abnormality. cDNA panhandle polymerase chain reaction (PCR) identified the fusion transcript, in which MLL exon 6 was fused in-frame with EB1 exon 5.
Screening for the prognostically important chromosome abnormalities (TEL-AML1, BCR-ABL, E2A-PBX1, and MLL) using multiplex reverse-transcription polymerase chain reaction was performed on 299 consecutive patients with ALL at 3 study centers (236 de novo, 63 at relapse), with the ethnic composition predominantly Chinese (51.8%) and Malay (34.8%).
Reciprocal chromosomal translocations involving the MLL gene at chromosome region 11q23 are recurring cytogenetic abnormalities in both de novo and therapy-related acute myeloid leukemia (AML) and in acute lymphoblastic leukemia.
Prognostic significance of additional cytogenetic aberrations in 733 de novo pediatric 11q23/MLL-rearranged AML patients: results of an international study.
Our results lend further support to the observation that the KMT2A-MAML2 fusion gene resulting from inv(11)(q21q23) is likely a recurrent cytogenetic abnormality in T-t-ALL and appears to be associated with pediatric cases.
Our cases add two new translocations to the list of chromosomal anomalies involving the long arm of chromosome 11, and show that apparent translocation t(11q23) may involve loci and genes other than MLL.
Moreover, 11 of 16 myeloid negative cases were also negative for any type of Bcr-Abl and MLL rearrangement, indicating that MPO mRNA positivity is not either invariably related to that chromosomal abnormality or necessarily associated with the presence of other myeloid differentiation features.
Masked MLL gene rearrangement was disclosed in the clinical course and sequential development of chromosome abnormality in a patient with therapy related acute myelogenous leukemia.
Infant acute lymphoblastic leukemia (ALL) is frequently characterized by the t(4;11)(q21;q23)cytogenetic abnormality encoding the MLL/AF4 oncogene, increased HOX gene expression and a pro-B/monocytoid phenotype.
In the second biopsy the hsr and MLL amplification appears as nonreciprocal translocation of multiple copies in the form of marked amplification of MLL on chromosome 16 in a background of increasing chromosomal aberrations.