Publications (10)25.39 Total impact
-
Article: PRDM16 (1p36) translocations define a distinct entity of myeloid malignancies with poor prognosis but may also occur in lymphoid malignancies.
[show abstract] [hide abstract]
ABSTRACT: The PRDM16 (1p36) gene is rearranged in acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) with t(1;3)(p36;q21), sharing characteristics with AML and MDS with MECOM (3q26.2) translocations. We used fluorescence in situ hybridization to study 39 haematological malignancies with translocations involving PRDM16 to assess the precise breakpoint on 1p36 and the identity of the partner locus. Reverse-transcription polymerase chain reaction (PCR) was performed in selected cases in order to confirm the partner locus. PRDM16 expression studies were performed on bone marrow samples of patients, normal controls and CD34(+) cells using TaqMan real-time quantitative PCR. PRDM16 was rearranged with the RPN1 (3q21) locus in 30 cases and with other loci in nine cases. The diagnosis was AML or MDS in most cases, except for two cases of lymphoid proliferation. We identified novel translocation partners of PRDM16, including the transcription factors ETV6 and IKZF1. Translocations involving PRDM16 lead to its overexpression irrespective of the consequence of the rearrangement (fusion gene or promoter swap). Survival data suggest that patients with AML/MDS and PRDM16 translocations have a poor prognosis despite a simple karyotype and a median age of 65 years. There seems to be an over-representation of late-onset therapy-related myeloid malignancies.British Journal of Haematology 11/2011; 156(1):76-88. · 4.94 Impact Factor -
Article: Morphology, cytogenetics, and survival in myelodysplasia with del(20q) or ider(20q): a multicenter study.
[show abstract] [hide abstract]
ABSTRACT: Isochromosome of the long arm of chromosome 20 with interstitial loss of material [ider(20q)] is a rare cytogenetic abnormality reported in myelodysplastic syndrome (MDS), with neither specific morphological pattern nor clear prognostic significance. The aim of this retrospective multicentric study is to compare the peripheral blood and bone marrow morphology of MDS patients with ider(20q) (n = 13) and del(20q) (n = 21) and controls (n = 47) in order to investigate whether the ider(20q) harbors specific morphological features. The secondary objective is to compare the outcome of patients from both groups. This study performed on the largest cohort of MDS patients with ider(20q) is the first that identifies specific morphological features (hypogranulated and vacuolized neutrophils and neutrophil erythrophagocytosis) allowing the identification of this cytogenetic abnormality with high sensitivity (70%) and specificity (85.7%). Suspected ider(20q) by morphology should therefore support targeted FISH tests in case of non informative karyotype. This combined approach will allow a better estimation of the prevalence of this underdiagnozed entity. The overall survival and progression-free survival did not statistically differ in both groups. However, hypogranulated and vacuolized neutrophils were significantly associated with survival.Annals of Hematology 07/2011; 91(2):203-13. · 2.62 Impact Factor -
Article: Correction: Refinement of 1p36 Alterations Not Involving PRDM16 in Myeloid and Lymphoid Malignancies.
[show abstract] [hide abstract]
ABSTRACT: [This corrects the article on p. e26311 in vol. 6.].PLoS ONE 01/2011; 6(12). · 4.09 Impact Factor -
Article: Refinement of 1p36 alterations not involving PRDM16 in myeloid and lymphoid malignancies.
[show abstract] [hide abstract]
ABSTRACT: Fluorescence in situ hybridization was performed to characterize 81 cases of myeloid and lymphoid malignancies with cytogenetic 1p36 alterations not affecting the PRDM16 locus. In total, three subgroups were identified: balanced translocations (N = 27) and telomeric rearrangements (N = 15), both mainly observed in myeloid disorders; and unbalanced non-telomeric rearrangements (N = 39), mainly observed in lymphoid proliferations and frequently associated with a highly complex karyotype. The 1p36 rearrangement was isolated in 12 cases, mainly myeloid disorders. The breakpoints on 1p36 were more widely distributed than previously reported, but with identifiable rare breakpoint cluster regions, such as the TP73 locus. We also found novel partner loci on 1p36 for the known multi-partner genes HMGA2 and RUNX1. We precised the common terminal 1p36 deletion, which has been suggested to have an adverse prognosis, in B-cell lymphomas [follicular lymphomas and diffuse large B-cell lymphomas with t(14;18)(q32;q21) as well as follicular lymphomas without t(14;18)]. Intrachromosomal telomeric repetitive sequences were detected in at least half the cases of telomeric rearrangements. It is unclear how the latter rearrangements occurred and whether they represent oncogenic events or result from chromosomal instability during oncogenesis.PLoS ONE 01/2011; 6(10):e26311. · 4.09 Impact Factor -
Article: Specific chromosomal IG translocations have different prognoses in chronic lymphocytic leukemia.
[show abstract] [hide abstract]
ABSTRACT: Chromosomal translocations are usually analyzed as a single entity, and are associated with a poor outcome in chronic lymphocytic leukemia. Translocations involving immunoglobulin genes are recurrent, but uncommon (<5%), and their individual prognosis is not clear. The two most frequent partners are BCL2 (18q21) and BCL3 (19q13). Herein, 75 cases are reported of chronic lymphocytic leukemia and t(14;18) (BCL2-CLLs). Our series benefits from morphological, immunological and cytogenetical reviews. The IGHV status analyses were performed by referring laboratories. Comparison was made with our previously published series of chronic lymphocytic leukemia patients with t(14;19) (BCL3-CLLs, n=29). Compared with BCL3-CLLs, lymphocytosis was lower in BCL2-CLLs (p<0.008), and splenomegaly was less frequent (p<0.0001). There were more "typical" morphologies (p<0.005) and Matutes scores >4 (p<0.001) in the BCL2-CLLs group, and less CD38 expression (p<0.04). More variant BCL2-translocations were observed (t(18;22), n=11; 2t(2;18), n=2; p<0.02), and BCL2-translocation was frequently single (p<0.002). Complex karyotypes (p<0.02), trisomy 12 (p<0.03), 6q deletion (p<0.002) and TP53 deletion (p<0.02) were less frequent in BCL2-CLLs, whereas 13q deletion was more frequent (p<0.005). The IGHV gene was frequently mutated in BCL2-CLLs (p<0.0001). Treatment-free survival was longer in BCL2-CLLs (p<0.0001). BCL2-CLL.S express CD5 and lack expression of CD38, and have a Matutes score ≥4, frequent trisomy 12, no ATM and 6q deletions, and a mutated IGHV status. Compared to BCL3-CLLs, BCL2-CLLs are much less aggressive; indicating that identifying individual translocations and cytogenetic partners would allow improved patient stratification.American journal of blood research. 01/2011; 1(1):13-21. -
Article: Chronic myeloproliferative disorder with t(8;22)(p11;q11) can mime clonal cytogenetic evolution of authentic chronic myelogeneous leukemia.
Genes Chromosomes and Cancer 08/2008; 47(10):915-8. · 3.31 Impact Factor -
Article: Mechanisms of genesis of variant translocation in chronic myeloid leukemia are not correlated with ABL1 or BCR deletion status or response to imatinib therapy.
[show abstract] [hide abstract]
ABSTRACT: Many published studies have indicated that various mechanisms could be involved in the genesis of variant chronic myelogeneous leukemia (CML) translocations. These are mainly one-step or two-step mechanisms, associated or not with deletions adjacent to the translocation junction on der(9) or der(22) chromosomes (or both). Based on the mechanism of genesis, it has been suggested that the complexity may affect the occurrence of ABL1 and BCR deletions (either or both), or may be associated with the CML disease course, and thus could determine the response to imatinib therapy. Through a retrospective molecular cytogenetic study of 41 CML patients with variant Philadelphia chromosome (Ph), we explored the genesis of these variant rearrangements and analyzed the correlation with deletion status and imatinib efficiency. Our results confirmed that the one-step mechanism is the most frequent, evidenced in 30 of 41 patients (73%); 3 patients demonstrated other more complex multistep events and 8 patients (19.5%) harbored ABL1 or BCR deletions that are not significantly associated with the complexity of translocation genesis. We also found no association between one-step, two-step, or multistep mechanisms and the response to imatinib therapy.Cancer Genetics and Cytogenetics 05/2008; 182(2):95-102. · 1.39 Impact Factor -
Article: Characterization by array-CGH of an interstitial de novo tandem 6p21.2p22.1 duplication in a boy with epilepsy and developmental delay.
[show abstract] [hide abstract]
ABSTRACT: We report on a 6-years-old boy with psychomotor retardation, mild dysmorphic features and behavioral disturbances associated with epilepsy. Conventional cytogenetic analysis concluded to an interstitial de novo 6p21.2p22.3 duplication. Molecular cytogenetic analysis, including array-CGH technology, allows characterization of this 7.3Mb interstitial tandem duplication. The phenotype of this small 6p duplication reported to date is compared to other cases in the literature. Presence of epilepsy, although rare in patients with 6p duplication may be linked to genes involved in brain function and synaptic transmission in the 6p21.2p22.1 duplicated region (GABBR1, BRD2 and GRM4).European Journal of Medical Genetics 04/2008; 51(4):373-81. · 2.18 Impact Factor -
Article: Acute megakaryoblastic leukemia with der(7)t(5;7)(q11;p11 approximately p12) associated with Down syndrome: a fourth case report.
Cancer Genetics and Cytogenetics 10/2006; 169(2):184-6. · 1.39 Impact Factor -
Article: Isolated tetrasomy 13: a fifth case report of a rare chromosome abnormality associated with poorly differentiated acute myeloid leukemia.
Cancer Genetics and Cytogenetics 08/2006; 168(2):181-2. · 1.39 Impact Factor
Top Journals
Institutions
-
2011
-
Cliniques Universitaires Saint-Luc
Brussels, BRU, Belgium
-