Cytogenetic and FISH analysis of 93 multiple myeloma Moroccan patients.

BACKGROUND: Multiple myeloma (MM) is a disease characterized by heterogeneous clinical presentations as well as complex genetic and molecular abnormalities. In MM, cytogenetic analysis is a challenge because of the low proliferation of malignant plasma cells. Thus, interphase fluorescence in situ hybridization (FISH), performed on sorted plasma cells detected abnormalities independently of a proliferative and infiltrative index. The purpose of this study was to explore, for the first time, the cytogenetic and molecular genetics features in Moroccan patients with multiple myeloma referred exclusively to National Reference Laboratory and to determine their risk stratification based on these features. METHODS: We performed cytogenetic analysis on 93 MM cases, all patients were subjected to FISH analysis, among which 45 patients have benefited from both FISH analysis and standard karyotype. RESULTS: Karyotype was normal in 78% (35/45) while, it was complex with varied structural and numerical abnormalities in 22% (10/45) of all patients, among which Hyperdiploid karyotype was found in 9% (n = 4 cases) and nonhyperdiploid in 13% (n = 6 cases). The most common numerical abnormalities were gains of chromosomes 3, 5, 9, 15, and 19. Whole chromosome losses were also frequent, affecting chromosomes X, 3, 14, 16 and 22. FISH analysis detected abnormalities in 50% of cases. The translocation t(4;14) and dup (1q) were the most frequent types of anomalies (14% and 13% respectively), followed by (17p) deletion and 14q32/IGH translocations with an undetermined origin (12% each) then the (1p) deletion (4%). For the normal karyotypes, FISH revealed chromosome abnormalities in 46%. CONCLUSION: This study compares the results of cytogenetic analysis of chromosomal abnormalities in the Moroccan population with other countries. ½ patient showed at least one type of molecular genetic abnormalities. Therefore, the introducing of the cytogenetic analysis is obligatory in the diagnosis of multiple myeloma.

Persistent polyclonal binucleated B-cell lymphocytosis and MECOM gene amplification.

BACKGROUND: Persistent Polyclonal Binucleated B-cell Lymphocytosis (PPBL) is characterized by a chronic polyclonal B-cell lymphocytosis with binucleated lymphocytes and a polyclonal increase in serum immunoglobulin-M. Cytogenetic is characterized by the presence of a supernumerary isochromosome +i(3)(q10), premature chromosome condensation and chromosomal instability. Outcome of PPBL patients is mostly benign, but subsequent malignancies could occur. The aim of our study is to provide an update of clinical and cytogenetic characteristics of our large cohort of PPBL patients, to describe subsequent malignancies occurring during the follow-up, and to investigate the role of the long arm of chromosome 3 in PPBL. RESULTS: We analyzed clinical, biological and cytogenetic characteristics (conventional cytogenetic analysis and fluorescent in situ hybridization) of 150 patients diagnosed with PPBL. We performed high-resolution SNP arrays in 10 PPBL patients, comparing CD19(+) versus CD19(-) lymphoid cells. We describe the cytogenetic characteristics in 150 PPBL patients consisting in the presence of supernumerary isochromosome +i(3)(q10) (59%) and chromosomal instability (55%). In CD19(+) B-cells, we observed recurrent copy number aberrations of 143 genes with 129 gains (90%) on 3q and a common minimal amplified genomic region in the MECOM gene. After a median follow-up of 60 months, we observed the occurrence of 12 subsequent malignancies (12%), 6 solid tumors and 6 Non-Hodgkin's Lymphomas, and 6 monoclonal gammopathies of undetermined significance (MGUS), requiring a long-term clinical follow-up. CONCLUSIONS: Our clinical and cytogenetic observations lead us to hypothesize that isochromosome 3q, especially MECOM abnormality, could play a key role in PPBL.

SET-NUP214 is a recurrent γδ lineage-specific fusion transcript associated with corticosteroid/chemotherapy resistance in adult T-ALL.

The SET-NUP214 (TAF1/CAN) fusion gene is a rare genetic event in T-cell acute lymphoblastic leukemia (T-ALL). Eleven (6%) of 196 T-ALL patients enrolled in the French Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL) 2003 and 2005 trials harbored a SET-NUP214 transcript. SET-NUP214-positive patients were predominantly (10 [91%] of 11) T-cell receptor (TCR)-negative and strikingly associated with TCRγδ lineage T-ALLs, as defined by expression of TCRγδ, TCRδ and/or TCRγ rearrangements but no complete TCRß variable diversity joining rearrangement in surface CD3/TCR-negative cases. When compared with SET-NUP214-negative patients, SET-NUP214-positive patients showed a significantly higher rate of corticosteroid resistance (91% vs 44%; P = .003) and chemotherapy resistance (100% vs 44%; P = .0001). All SET-NUP214-positive patients but one achieved complete remission, and 9 were allografted. Despite the poor early-treatment sensitivity, the outcome of SET-NUP214-positive patients was similar to that of SET-NUP214-negative patients.

Morphologic features of binucleated lymphocytes to assess the diagnosis of persistent B-cell polyclonal lymphocytosis or other mature B-cell neoplasms.

The observation of binucleated lymphocytes (BNLs) on a peripheral blood smear is essential to the diagnosis of persistent polyclonal B-cell lymphocytosis (PPBL). Only a few case reports have mentioned their presence in other contexts, mainly mature B-cell neoplasms such as chronic lymphocytic leukemia or reactive circumstances such as multiple sclerosis undergoing natalizumab treatment. We sought to investigate whether any particular morphologic features of BNL were more specific to PPBL than other diseases. We reviewed peripheral blood smears of a series of patients affected by PPBL or harboring BNLs whatever the diagnosis. We found that BNLs in PPBL were heterogeneous, but mostly medium-sized with a moderately abundant basophilic cytoplasm, sometimes vacuolated. The chromatin was mature in an asymmetrically bilobed nucleus showing one to two nucleoli. Though mainly observed in patients with PPBL, all these criteria remained non-specific. Conversely, the presence of either monocytoid or hyperbasophilic cells had clinical value to confirm PPBL. We conclude that a substantial percentage of BNLs possessing the morphologic features described and observed in a context of monocytoid and/or hyperbasophilic lymphocytes is predictive of the diagnosis of PPBL.

[Morphologic features of the binucleated lymphocytes for the assesment of persistent B-cell polyclonal lymphocytosis]. / Intérêt de l'étude morphologique des lymphocytes binucléés pour le diagnostic des lymphocytoses.

Observation of binucleated lymphocytes on a blood film is a cornerstone event to assess persistent polyclonal B-cell lymphocytosis diagnosis (PPBL). But seldom case reports mentioned their finding in other contexts, mainly B-cell lymphoproliferative neoplasms such chronic lymphocytic leukemia or in reactive circumstances as multiple sclerosis undergoing natalizumab treatment. We aimed to check if some particular morphologic features were more specificaly linked to PPBL, reviewing blood films of series of patients affected by PPBL or harbouring binucleated lymphocytes whatever the diagnosis was. We found that binucleated cells in PPBL were heterogeneous but mostly midde-sized cells, asymetricaly bilobed with nucleoli, and with a moderately basophilic cytoplasm. Though mainly observed in PPBL patients, all that criteria remained unspecific. Conversely, the morphologic features of the other lymphoid cells were of good clinical value to affirm PPBL, either monocytoid or hyperbasophilic cells being systematically found. We think that a substantial percentage of binucleated lymphocytes, harbouring morphologic features such as described, and in a context of monocytoid and/or hyperbasophilic lymphocytes is predictive of PPBL diagnosis.

Toward a NOTCH1/FBXW7/RAS/PTEN-based oncogenetic risk classification of adult T-cell acute lymphoblastic leukemia: a Group for Research in Adult Acute Lymphoblastic Leukemia study.

PURPOSE: The Group for Research in Adult Acute Lymphoblastic Leukemia (GRAALL) recently reported a significantly better outcome in T-cell acute lymphoblastic leukemia (T-ALL) harboring NOTCH1 and/or FBXW7 (N/F) mutations compared with unmutated T-ALL. Despite this, one third of patients with N/F-mutated T-ALL experienced relapse. PATIENTS AND METHODS: In a series of 212 adult T-ALLs included in the multicenter randomized GRAALL-2003 and -2005 trials, we searched for additional N/K-RAS mutations and PTEN defects (mutations and gene deletion). RESULTS: N/F mutations were identified in 143 (67%) of 212 patients, and lack of N/F mutation was confirmed to be associated with a poor prognosis. K-RAS, N-RAS, and PTEN mutations/deletions were identified in three (1.6%) of 191, 17 (8.9%) of 191, and 21 (12%) of 175 patients, respectively. The favorable prognostic significance of N/F mutations was restricted to patients without RAS/PTEN abnormalities. These observations led us to propose a new T-ALL oncogenetic classifier defining low-risk patients as those with N/F mutation but no RAS/PTEN mutation (97 of 189 patients; 51%) and all other patients (49%; including 13% with N/F and RAS/PTEN mutations) as high-risk patients. In multivariable analysis, this oncogenetic classifier remained the only significant prognostic covariate (event-free survival: hazard ratio [HR], 3.2; 95% CI, 1.9 to 5.15; P < .001; and overall survival: HR, 3.2; 95% CI, 1.9 to 5.6; P < .001). CONCLUSION: These data demonstrate that the presence of N/F mutations in the absence of RAS or PTEN abnormalities predicts good outcome in almost 50% of adult T-ALL. Conversely, the absence of N/F or presence of RAS/PTEN alterations identifies the remaining cohort of patients with poor prognosis.

Chromosomal aberrations and their prognostic value in a series of 174 untreated patients with Waldenström's macroglobulinemia.

Waldenström's macroglobulinemia is a disease of mature B cells, the genetic basis of which is poorly understood. Few recurrent chromosomal abnormalities have been reported, and their prognostic value is not known. We conducted a prospective cytogenetic study of Waldenström's macroglobulinemia and examined the prognostic value of chromosomal aberrations in an international randomized trial. The main aberrations were 6q deletions (30%), trisomy 18 (15%), 13q deletions (13%), 17p (TP53) deletions (8%), trisomy 4 (8%), and 11q (ATM) deletions (7%). There was a significant association between trisomy of chromosome 4 and trisomy of chromosome 18. Translocations involving the IGH genes were rare (<5%). Deletion of 6q and 11q, and trisomy 4, were significantly associated with adverse clinical and biological parameters. Patients with TP53 deletion had short progression-free survival and short disease-free survival. Although rare (<5%), trisomy 12 was associated with short progression-free survival. In conclusion, the cytogenetic profile of Waldenström's macroglobulinemia appears to differ from that of other B-cell lymphomas. Chromosomal abnormalities may help with diagnosis and prognostication, in conjunction with other clinical and biological characteristics.

Atlas of genetics and cytogenetics in oncology and haematology in 2013.

The Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://AtlasGeneticsOncology.org) is a peer-reviewed internet journal/encyclopaedia/database focused on genes implicated in cancer, cytogenetics and clinical entities in cancer and cancer-prone hereditary diseases. The main goal of the Atlas is to provide review articles that describe complementary topics, namely, genes, genetic abnormalities, histopathology, clinical diagnoses and a large iconography. This description, which was historically based on karyotypic abnormalities and in situ hybridization (fluorescence in situ hybridization) techniques, now benefits from comparative genomic hybridization and massive sequencing, uncovering a tremendous amount of genetic rearrangements. As the Atlas combines different types of information (genes, genetic abnormalities, histopathology, clinical diagnoses and external links), its content is currently unique. The Atlas is a cognitive tool for fundamental and clinical research and has developed into an encyclopaedic work. In clinical practice, it contributes to the cytogenetic diagnosis and may guide treatment decision making, particularly regarding rare diseases (because they are numerous and are frequently encountered). Readers as well as the authors of the Atlas are researchers and/or clinicians.

Clinical-grade production of human mesenchymal stromal cells: occurrence of aneuploidy without transformation.

Clinical-grade human mesenchymal stromal cells (MSCs) have been expanded in vitro for tissue engineering or immunoregulatory purposes without standardized culture conditions or release criteria. Although human MSCs show poor susceptibility for oncogenic transformation, 2 recent studies described their capacity to accumulate chromosomal instability and to give rise to carcinoma in immunocompromised mice after long-term culture. We thus investigated the immunologic and genetic features of MSCs expanded with fetal calf serum and fibroblast growth factor or with platelet lysate in 4 cell-therapy facilities during 2 multicenter clinical trials. Cultured MSCs showed a moderate expression of human leukocyte antigen-DR without alteration of their low immunogenicity or their immunomodulatory capacity. Moreover, some transient and donor-dependent recurring aneuploidy was detected in vitro, independently of the culture process. However, MSCs with or without chromosomal alterations showed progressive growth arrest and entered senescence without evidence of transformation either in vitro or in vivo.

Gain of the short arm of chromosome 2 (2p) is a frequent recurring chromosome aberration in untreated chronic lymphocytic leukemia (CLL) at advanced stages.

Using array-based CGH, we identified 2p gain in 22/78 (28%) untreated Binet stages B/C CLL, which was the second most frequent copy number change after 13q deletion. It never occurred as a sole abnormality and was associated with other changes (6q deletion; 1p gain). The region of 2p gain frequently included two oncogenes, REL and MYCN. All patients with gain of REL were unmutated for IGHV (p=0.03). Gain of MYCN was associated with increased mRNA expression (p=0.005), suggesting a pathogenic role for MYCN. Gain of 2p appears to be a marker of progression and may contribute to the poor prognosis.

Polyclonal B-cell lymphocytosis with binucleated lymphocytes (PPBL).

Persistent polyclonal B-cell lymphocytosis (PPBL) is a rare and recently described entity. The review of the literature show PPBL is diagnosed predominantly but not exclusively in women, usually smokers. PPBL is recognized by a moderate, chronic and absolute lymphocytosis (>4 × 10(9)/l) in the peripheral blood. In 10% of cases without lymphocytosis, the PPBL diagnosis has to be suggested by peripheral blood examination showing in all cases atypical binucleated lymphocytes. A polyclonal serum IgM is also associated and HLA-DR7 expression is present in most cases. Contrary to B-cell chronic lymphoproliferative disorders (B-CLPD), peripheral B cells are polyclonal with kappa and lambda light-chain expression and no clonal rearrangement of immunoglobulin heavy chain genes is usually demonstrated. The detection of an extra isochromosome for the long arm of chromosome 3 +i(3)(q10) has to be considered as a specific marker of PPBL. We performed conventional cytogenetic analysis (CCA) in 111 patients with typical PPBL we followed-up more than 4 years. +i(3q) was detected in 34% (33/98), PCC in 8% (8/98) and both abnormalities in 31% (30/98). CCA showed neither +i(3q) nor PCC in 28% (27/98). Fluorescence in situ hybridization (FISH) was also performed in 84 cases and +i(3q) was detected in 71% (60/84). When combining both procedures in 84 patients, +i(3q) was detected in 17 patients with negative CCA and was confirmed in 43 patients with positive CCA. CCA and FISH were both negative in 24 cases. Whether patients with PPBL are at increased risk of hematological malignancy remains unclear. After a median follow-up of 4.4 years, most PPBL patients presented a stable clinical and biological course. Six patients died from pulmonary cancer, myocardial infarction, cerebral aneurysm rupture or diffuse large B-cell lymphoma. Two patients had IgM monoclonal gammopathy of undetermined significance (MGUS) at the time of PPBL diagnosis and two other patients developed IgM MGUS respectively 12 and 22 years after PPBL diagnosis. A malignant non Hodgkin's lymphoma (NHL) appeared in 3 additional patients: two patients presented diffuse large B cell lymphoma and 1 patient a splenic marginal zone lymphoma. In conclusion, the possibility of PPBL to evolve toward a clonal proliferation, malignant lymphoma or secondary solid cancer lead us to consider PPBL not as a benign pathology. We recommend a careful and continued clinical and biological long-term follow-up in all PPBL patients.

A report from the LALA-94 and LALA-SA groups on hypodiploidy with 30 to 39 chromosomes and near-triploidy: 2 possible expressions of a sole entity conferring poor prognosis in adult acute lymphoblastic leukemia (ALL).

To reveal the relationship between hypodiploidy with 30 to 39 chromosomes and near-triploidy in acute lymphoblastic leukemia (ALL), we studied 24 patients presenting with one of these aneuploidies among 623 adults with ALL registered in the Leucemie Aigue Lymphoblastique de l'Adulte (LALA) protocols. The 2 ploidy groups presented a striking similarity of their cytogenetic profiles: chromosomes 2, 3, 4, 7, 13, 15, 16, and 17, significantly monosomic in hypodiploidy 30 to 39, were also frequently disomic in near-triploidy, whereas those retained in pairs in hypodiploidy 30 to 39 were frequently tetrasomic in near-triploidy. DNA content data revealed the simultaneous presence of 2 aneuploid peaks in most tested cases (DNA indexes: 0.72-0.87/1.39-1.89) and a multiple correspondence analysis applied on cytogenetic profiles ascertained their strong relationship. We thus assumed that near-triploidy derives from the duplication of hypodiploidy with 30 to 39 chromosomes and that both aneuploid groups are 2 expressions of the same disease. These 24 patients presented with B-cell phenotype, low leukocytoses (median white blood cell count, 4.2 x 10(9)/L), and poor prognosis (complete remission, 57%; median disease-free-survival, 8 months; median survival, 10.4 months) comparable to that of Ph(+) patients treated according to the same protocol. We suggest that hypodiploidy with 30 to 39 chromosomes or near-triploidy should be regarded as a new high-risk factor in the risk stratification of adult ALL protocols.