Leukemia Research

Editorial Board

2010-04-01

Right and left shifts for age in MDS

Semra Paydas — 2010-04-01

Myelodysplasia is a Greek word meaning “morphological abnormality of the marrow” and may be seen in different disorders including autoimmune/infective/chronic diseases, megaloblastic anemias, and toxic susbstance exposure. For this reason myelodysplasia requires a long list of differential diagnoses. The myelodysplastic syndrome (MDS) diagnosis is based on the exclusion of other disorders and is characterized by ineffective hematopoiesis, quantitative/qualitative cellular defects and moderate risk of leukemic transformation. Abnormal differentiation/maturation of myeloid cells, bone marrow failure and genetic instability are the hallmarks of this heterogenous entity. In clinical practice the first step is to differentiate myelodysplasia from MDS. Diagnosis of MDS requires a team of expert pathologists, expert biologist in cytogenetics, a skilled/carefully working/clearly thinking clinician. Additionally a good cooperation between clinician and pathologist is essential step. FAB classification is the first classification of MDS based on morphologic criteria. The prognosis and clinical picture of MDS depends on patient related factors (age, gender, co-morbidity), subgroup of the disease, affected cell types and involved genes in the neoplastic process . Risk stratification for prognosis and management is necessary for all patients according to the IPSS which is based on the percentage of BM blasts, cytogenetics and the number of cytopenias. WHO classification is a more mature classification system and covers morphologic criteria for dysplasia, cytogenetics and percentage of blasts in peripheral blood and bone marrow. WPSS is the last prognostic scoring system and highly useful in identifying risk groups in this complex entity . Although scoring and stratification of the MDS patients are essential importance, main problems begin at this point: cytogenetic evaluation is not performed always for a variety of reasons. However, more and more commercial laboratories have become available, particularly in the U.S.A., at a reasonable cost. In the developing countries this may not be possible or practical except in tertiary care centers. The absence of cytogenetic data does not permit to determine the prognostic data. Furthermore, MDS case series diagnosed without cytogenetic information are not accepted as paper in most of the journals. For this reason we have not enough data for the majority of these cases from underdeveloped countries which has some demographical differences from developed countries. As presented by Golagan et al. in this issue, younger age is an important property of these cases . We are not aware of an important part the MDS cases in the world and this is an important disadvantage for clinicians working at hematology/oncology field. As a result we have information about the biology and outcome of MDS: only in the older patients and coming from developed countries.

Captivating Bortezomib: An active but still mysterious drug

Francesco Di Raimondo, Concetta Conticello — 2010-04-01

Bortezomib is an inhibitor of the proteasome that represents one of the most intriguing drugs that has been recently introduced in clinical practice. Its use in the treatment of multiple myeloma has increased percentage of complete response and, most remarkably, it has improved disease free and overall survival, thus playing a pivotal role in the treatment of this disease . The activity of Bortezomib is not limited to myeloma since it has recently received the approval for treatment of relapsed mantle cell lymphoma patients and several clinical trials are currently conducted in the United States and around the world on different malignancies (www.clinicaltrials.gov). Notwithstanding the clinical successes, there is a gap between what we know on the in vitro activity of this drug and its clinical activity.

Adding FISH to karyotype in Myelodysplastic syndrome investigation diagnosis: Are all questions answered?

Maria de Lourdes L.F. Chauffaille — 2010-04-01

Myelodysplastic syndrome (MDS) represents a group of clonal hematopoietic disorders characterized by ineffective hematopoiesis. Despite peripheral cytopenias, bone marrow is usually hypercellular with morphological dysplasia, increased apoptosis, genetic instability and an additional risk to evolve to acute leukemia in around 30% of the cases .

Tumor suppression in T cell leukemia—The role of Ikaros

Sinisa Dovat, Kimberly J. Payne — 2010-04-01

The Ikaros gene encodes a DNA-binding protein that belongs to the C2H2 zinc finger gene family . Early biological experiments using mutant mouse models demonstrated that a lack of Ikaros expression in mice results in the absence of B, NK and dendritic cells, with a decreased number of T cells . These experiments established Ikaros as a master-regulator of lymphoid development. Subsequent analysis of Ikaros-deficient mice revealed that the absence of Ikaros expression, or the presence of dominant-negative Ikaros mutants, leads to the development of T cell leukemia in mice. This suggested that Ikaros acts as a tumor suppressor . The identification of Ikaros as a master-regulator of lymphoid development and a tumor suppressor provided a novel model to study the development of leukemia, as well as tumor suppression, and raised hopes that Ikaros function might be important for tumor suppression in human leukemia. Ikaros was confirmed as a true tumor suppressor in the mouse by experiments in which the introduction of wild-type Ikaros into an Ikaros-deficient early-T leukemia cell line induced growth arrest along with T cell differentiation . Ikaros has been shown to directly inhibit expression of the Notch target genes Hes-1 and Deltex suggesting that one possible mechanism for Ikaros-mediated suppression of leukemia involves inhibition of the Notch signaling pathway.

Pediatric acute lymphoblastic leukemia: There is no TEL-ing what wonders lie ahead

Claudio Sandoval — 2010-04-01

The advent of molecular medicine has allowed physicians and scientists to decipher some of nature's mysteries. Few stories are more exhilarating than that of the successes in pediatric acute lymphoblastic leukemia (ALL) and chronic myelogenous leukemia (CML). Indeed, children with ALL are now curable without the need for cranial radiation and imatinib mesylate has changed the landscape of CML therapy . Despite these advances disease recurrence and adverse late effects continue to dampen our celebrations. Enticing dormant cancer stem cells to undergo mitosis and offering risk-directed therapy are current endeavors aimed to overcome these obstacles.

FISH analysis in addition to G-band karyotyping: Utility in evaluation of myelodysplastic syndromes?

2010-04-01

Abstract: Cytogenetic analysis provides important diagnostic and prognostic information for patients with myelodysplastic syndromes (MDS). Prior studies, mostly comprised of small sample sizes, have reported conflicting results while evaluating the usefulness of FISH in addition to G-band karyotyping in MDS. In the current study, the utility of performing a tailored FISH panel, in addition to G-band karyotyping was evaluated in a series of 110 MDS patients diagnosed at our institute. Using our FISH panel, clonal cytogenetic abnormalities were detected in 3/8 (38%) of MDS cases with karyotype failure and in 5/54 (9%) cases with normal G-band karyotypes, all the latter had intermediate or high grade MDS. Of the cases with abnormal G-band karyotypes, 6/48 (13%) showed discrepancies between FISH and G-band results, however, FISH analysis only lead to reassignment of karyotypic abnormalities to different chromosomes, MDS cytogenetic risk stratification was not altered. Our findings suggest that FISH testing is informative only in MDS cases with karyotype failure and intermediate-high grade MDS cases with normal G-band karyotype and has limited utility in cases that have normal G-band karyotypes and morphologic features of low grade MDS or in cases with abnormal G-band karyotypes.

Genetic inactivation of Ikaros is a rare event in human T-ALL

2010-04-01

Abstract: The Ikaros (Ikzf1) gene, encoding a transcription regulator, is a major tumor suppressor in B-cell acute lymphoblastic leukemia (B-ALL). In the mouse, however, loss of Ikaros is primarily associated with T-ALL development. Whether Ikaros is also implicated in human T-ALL remains unclear. We studied Ikaros in 25 human T-ALL samples from diverse molecular subtypes at the mRNA, protein, sequence and genomic copy number level. We found that Ikaros was abnormal in only one sample: one allele was lost by genomic deletion, while proteins generated from the remaining allele were delocalized and concentrated at a single cytoplasmic structure. Thus, inactivation of Ikaros by deletion or mutation is rare in human T-ALL.

CD9 expression can be used to predict childhood TEL/AML1-positive acute lymphoblastic leukemia: Proposal for an accelerated diagnostic flowchart

2010-04-01

Abstract: CD9 has been shown to be differentially expressed in childhood TEL/AML1-positive acute lymphoblastic leukemia (ALL). We confirmed this finding in large Affymetrix data sets and in 80 new cases at both RNA and protein levels. Moreover, we showed that mean fluorescence intensity of CD9 by flow cytometry can distinguish TEL/AML1-positive ALL from other BCP-ALL. Using ROC analysis, the most efficient model for predicting TEL/AML1-positive ALL combined CD9 (mean fluorescence intensity ≤20) and CD10 values (positive cells >40%). Finally, we propose a faster procedure for optimizing the diagnosis of childhood BCP-ALL subgroups.

Acute lymphoplasmacytoid dendritic cell (DC2) leukemia: Results from the Hellenic Dendritic Cell Leukemia Study Group

2010-04-01

Abstract: We present a cohort of 22 patients with type 2 dendritic cell (DC2) acute leukemia (or blastic plasmacytoid dendritic cell neoplasm-BPDCN, as it has been recently named), diagnosed in Greece over the past 12-year period, according to the main clinical and immunophenotypic features of this entity. Four additional cases are discussed, classified as leukemia of ambiguous lineage (LAL), because of the simultaneous detection of a CD56 negative DC2 population and of a second myeloid precursor cell population. The morphological features and cytogenetic findings of the typical BPDCN cases were similar to those previously described. Acute lymphoblastic leukemia-type chemotherapeutic regimens were more efficient in controlling the disease. Immunophenotyping of typical BPDCN cases revealed CD4+, CD56+, HLA-DR+ and CD123bright neoplastic cells, in the absence of major B-, T- and myeloid-associated markers, while the phenotype of the four cases characterized as LAL highlights the risk of misdiagnosis. Based on our experience, we propose a flow cytometric algorithmic approach for the distinction of typical BPDCN from certain types of acute myeloid leukemia, but also for the identification of acute myeloid leukemia, admixed with CD56 negative DC2 cells, which could be misdiagnosed as BPDCN.

FISH and SNP-A karyotyping in myelodysplastic syndromes: Improving cytogenetic detection of del(5q), monosomy 7, del(7q), trisomy 8 and del(20q)

2010-04-01

Abstract: Cytogenetic aberrations identified by metaphase cytogenetics (MC) have important diagnostic, prognostic and therapeutic roles in myelodysplastic syndromes (MDS). Fluorescence in situ hybridization (FISH) complements MC by the ability to evaluate large numbers of both interphase and metaphase nuclei. However, clinically practical FISH strategies are limited to detection of known lesions. Single nucleotide polymorphism array (SNP-A)-based karyotyping can reveal unbalanced defects with superior resolution over MC and FISH and identify segmental uniparental disomy (UPD) undetectable by either method. Using a standardized approach, we focused our investigation on detection of −5/del(5q), −7/del(7q), trisomy 8 and del(20q) in patients with MDS (N=52), MDS/myeloproliferative overlap syndromes (N=7) and acute myeloid leukemia (N=15) using MC, FISH and SNP-A karyotyping. The detection rate for del(5q) was 30, 32 and 32% by MC, FISH, and SNP-A, respectively. No single method detected all defects, and detection rates improved when all methods were used. The rate for detection of del(5q) increased incrementally to 35% (MC+FISH), 38% (MC+SNP-A), 38% (FISH+SNP-A) and 39% (all three methods). Similar findings were observed for −7/del(7q), trisomy 8 and −20/del(20q). We conclude that MC, FISH and SNP-A are complementary techniques that, when applied and interpreted together, can improve the diagnostic yield for identifying genetic lesions in MDS and contribute to the better description of abnormal karyotypes.

Expression of the human concentrative nucleotide transporter 1 (hCNT1) gene correlates with clinical response in patients affected by Waldenström's Macroglobulinemia (WM) and small lymphocytic lymphoma (SLL) undergoing a combination treatment with 2-chloro-2′-deoxyadenosine (2-CdA) and Rituximab

2010-04-01

Abstract: Purpose: Resistance to nucleoside analogues agents is likely to be multifactorial and could involve a number of mechanisms affecting drug penetration, metabolism and targeting. In vitro studies of resistant human cell lines have confirmed that human concentrative nucleoside transporter 1 (hCNT1)-deficient cells display resistance.Experimental design: We applied real-time PCR method to assess the mRNA expression of equilibrative and concentrative nucleoside transporter (hENT1, hCNT1), deoxycytidine and deoxyguanosine kinase (dCK, dGK), 5′-nucleotidase (5′-NT), ribonucleotide reductase catalytic and regulatory (RR1, RR2) subunits in bone marrow cells from 32 patients with Waldenström's Macroglobulinemia (WM) and small lymphocytic lymphoma (SLL) who received 2CdA-based chemotherapy. Responses to chemotherapy, were then correlated to the expression of these markers.Results: All 32 patients enrolled expressed lower levels of hCNT1 as compared to healthy donors. In univariate analysis, lower expression level of hCNT1 (p=0.0021) and RR2 (p=0.02) correlated with response to chemotherapy. In particular, patients with low levels of hCNT1 achieved inferior clinical response. No significant correlation between these genes expression and age, stage of disease was found. This study suggests that nucleotidase expression levels can be used to identify subgroups of WM and SLL patients who will likely respond differently to a 2CdA-based therapy.

Analyses on clinical characteristic and prognoses of 41 patients with chronic myelomonocytic leukemia in China

2010-04-01

Abstract: Purpose: To investigate clinical characteristic and prognostic factors for chronic myelomonocytic leukemia (CMML).Methods: A retrospective cohort study was used in the research. We investigated clinical and laboratory characteristics of CMML patients and survival status. Patients were followed up regularly through out the course of the research.Results: Forty-one cases were diagnosed as CMML, including 27 male and 14 female patients. Median WBC was 13.7×109/L. Five patients had leukocytopenia (1.92–3.46×109/L). Median monocyte count in the peripheral blood was 2.13×109/L. All patients presented with bone marrow dysplasia, and most showed hyperplasia, except 3 cases. Abnormal chromosome was detected in 34% cases. Median survival time for CMML-1 and CMML-2 was 20 and 12 months, respectively, but there were no statistical significance of survival duration between them. Univariable analysis showed that age (>60 years), neutrophil count (<2.0×109/L), lymphocyte count (<1.0×109/L), mature monocyte count (≥5×109/L) and anemia (Hb<60g/L) were associated with poor prognosis for CMML. There was no statistical significance in LDH, gender, and abnormal chromosome for survival time. Only lymphocyte count and neutrophil count in peripheral blood were independent prognostic factors for CMML after multivariate analysis.Conclusion: CMML mainly occurs in elderly patients. Although most patients have leukocytosis and monocytosis at diagnosis, few cases show leucopenia and monocytopenia. Age, neutrophil, lymphopenia, monocytosis, and severe anemia are associated with inferior prognosis of CMML. Lymphocyte<1.0×109/L and neutrophil count<2.0×109/L are adversely independent prognostic factors for CMML.

Elevated mRNA level of hST6Gal I and hST3Gal V positively correlates with the high risk of pediatric acute leukemia

Susmita Mondal, Sarmila Chandra, Chitra Mandal — 2010-04-01

Abstract: Altered sialylation occurs in essentially all types of human and experimental cancers. Although, aberrant sialylation is believed to mainly due to altered sialyltransferase (ST) level, so far, expression pattern of different STs in acute lymphoblastic leukemia has never been investigated. Accordingly, the aim of our study was to monitor the changes in mRNA expression of ST6Gal I, ST3Gal V and ST8Sia I in patients by real-time PCR, which may provide prognostic information useful in defining appropriate therapeutic options. Our data demonstrated that ST6Gal I and ST3Gal V mRNA were up-regulated in lymphoblasts whereas its presence was negligible in non-malignant donors. In contrast, ST8SiaI was downregulated in patients. The extents of linkage-specific sialylation of glycoconjugates were found to be associated with disease establishment. Additionally, ST6Gal I and ST3Gal V were positively correlated with the high risk of the disease (P=0.0032 and 0.0016). This differential ST level can be used as biomarker with the molecular method of quantitative PCR and may be useful to discriminate normal and cancer patients.

Bortezomib-induced peripheral neuropathy in multiple myeloma: A comparison between previously treated and untreated patients

2010-04-01

Abstract: Peripheral neuropathy (PN), with neuropathic pain as main symptom, represents the dose-limiting toxicity of the proteasome inhibitor bortezomib. Aim of this study was to compare the incidence, risk factors, severity and outcome of PN and neuropathic pain in patient treated with bortezomib up-front or at relapse. We studied 55 patients with multiple myeloma (MM) who received bortezomib as first line therapy and 70 pre-treated patients who received bortezomib in relapse or progression. Regarding PN, no differences were found among untreated and pre-treated patients in the incidence (55% vs 52%, p=0.43), severity (NCI grade 3–4 9% vs 14%, p=0.27), and outcome (improved/resolved 90% vs 91%, p=0.58). Concerning neuropathic pain, the incidence was lower (50% vs 81%, p=0.008) and solved earlier (35 days vs 91 days, p=0.02) in untreated compared with pre-treated patients. Untreated patients needed dose modification less frequently (36% vs 73%, p=0.012). No correlation was found between development of PN and prior exposure to potentially neurotoxic drugs such as thalidomide, vincristine, and cysplatin. Age represented the main risk factor for PN (p=0.036) with an increase in risk of PN amounting to 6% per year of age. In conclusion, incidence, severity and outcome of bortezomib-related PN are similar in untreated and pre-treated MM patients except for neuropathic pain which has lower incidence and shorter duration in untreated patients with less frequent need for bortezomib discontinuation. Age emerges as the most relevant risk factor for peripheral neuropathy, with a risk increase for PN of 6% per year of age.

ALK-negative anaplastic large cell lymphoma with extensive peripheral blood and bone marrow involvements manifested as “leukemic phase”

Ying Lu, Xiaohui Zhao, Endi Wang, Wei Chen, Qin Huang — 2010-04-01

Abstract: CD30-positive anaplastic large cell lymphoma (ALCL) is a distinctive malignant large cell lymphoma of T-cell lineage, often presenting in lymph node or extranodal sites. ALCL cases with extensive bone marrow and peripheral blood involvement manifested as “leukemic phase” are extremely rare and the most of those cases reported are anaplastic large cell lymphoma kinase (ALK) positive ALCL in childhood population. Here we report four adult cases of ALK-negative ALCL with extensive bone marrow and peripheral blood involvement manifested as “leukemic phase”. Circulating large lymphoma cells varied from 20 to 80% in peripheral blood and bone marrow biopsy showed various nodular or interstitial infiltrates. By reviewing the clinicopathologic data of previously reported ALCL cases with extensive bone marrow and peripheral blood involvement, there appears to be of large variations in regard to the patient's age, morphologic variants, immunophenotypic or genotypic characteristics of the disease. While most cases of ALCL with peripheral blood and bone marrow involvement were ALK-positive or carrying t(2;5) translocation, rare ALK-negative cases were also present. Leukemic ALCL patients usually have unfavourable prognosis, regardless of ALK expression.

T-cell lymphoblastic leukemia in early childhood presents NOTCH1 mutations and MLL rearrangements

2010-04-01

Abstract: T-cell acute lymphoblastic leukemia (T-ALL) may affect children in very early age. However, the critical events leading to this brief latency is still unclear. We used standard methods to explore NOTCH1 mutations and other specific molecular markers in 15 early childhood T-ALL cases. Most of them consisted of immature differentiation subtype. Despite being found in a lower frequency than that described for overall pediatric T-ALL, NOTCH1 alterations were the most frequent ones. Other alterations included MLL+ (n=4), SIL-TAL1+ (n=3), FLT3 mutation (n=1) and HOX11L2+ (n=1). Our results suggest that NOTCH1 and MLL abnormalities are primary leukemogenic hits in early T-ALL.

Phase I trials of amonafide as monotherapy and in combination with cytarabine in patients with poor-risk acute myeloid leukemia

2010-04-01

Abstract: Amonafide-l-malate (amonafide) is a unique DNA intercalator that maintains activity in the presence of MDR mechanisms, a frequent cause of treatment-failure in secondary AML. 43 patients with relapsed/refractory or secondary AML or CML blast crisis were enrolled into two phase I dose-escalation studies investigating amonafide as monotherapy or in combination with cytarabine. 3/17 patients in the monotherapy trial and 10/26 patients in the combination trial achieved a complete remission. Between both trials responses occurred in 9/20 patients with secondary AML. Both trials demonstrated an acceptable safety profile and significant antileukemic activity in patients with poor-risk AML, especially those with secondary AML.

Polymorphisms in glucocorticoid receptor gene and the outcome of childhood acute lymphoblastic leukemia (ALL)

2010-04-01

Abstract: Childhood acute lymphoblastic leukemia patients (n=310) were analyzed for four SNPs in the NR3C1 gene. Polymorphisms −627A/G, intron 2 +646C/G and 9bT/C were all associated with reduced event-free survival. Haplotypes composed of AGT alleles at these loci and tagged by the intron 2 +646G variant also associated with lower event-free survival (p=0.03). The progressive impact of this haplotype on outcome was seen with two copies associated with reduced overall survival (p=0.05). Quantitative mRNA analysis in lymphoblastoid cell lines showed that carriers of the AGT haplotype had a higher ratio of GR γ/α isoforms (p=0.04), which possibly explains its association with reduced event-free survival and overall survival.

Proteasome inhibitor-induced apoptosis in acute myeloid leukemia: A correlation with the proteasome status

2010-04-01

Abstract: The proteasome plays a critical role in the regulation of many cellular processes, including the cell cycle and tumor growth. The proteasome inhibitor bortezomib has recently been approved for the treatment of relapsed and refractory multiple myeloma. In this study, we investigated the induction of apoptosis by proteasome inhibitors in several human acute myeloid leukemia (AML) cell lines and in primary cells from patients. We demonstrate that these drugs induce a high level of apoptosis in the KG1a cell line, in which the therapeutic drug daunorubicin is poorly active, compared to other AML cell lines. In parallel, we found that significantly different levels of apoptosis were induced in primary cells from patients depending on the FAB-based differentiation status of these cells. Moreover, the level of 20S proteasome in KG1a cells was also high compared to other AML cell lines, suggesting a relationship between the high sensitivity to proteasome inhibitors and an elevated amount of 20S proteasome. In good accordance, we identified two groups of patient cells expressing high and low levels of 20S proteasome, with respective high and low sensitivity to proteasome inhibitors. Further comparison of the proteasome status in KG1a and U937 cells also suggests that a high proportion of the 19S regulatory complex in U937 cells compared to the 20S core complex may explain an increased proteasome activity. Altogether, our results suggest that various AML subtypes may present different responses to proteasome inhibitors, that these molecules can be potentially considered as interesting therapeutic alternatives for these pathologies, and that the amount of 20S proteasome in AML cells may be predictive of the cellular response to these inhibitors.

The role of p38 mitogen-activated protein kinase in serum-induced leukemia inhibitory factor secretion by bone marrow stromal cells from pediatric myelodysplastic syndromes

2010-04-01

Abstract: Stromal cells from pediatric myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) associated with MDS (MDS-AML) present high expression of leukemia inhibitor factor (LIF). We demonstrated using mitogen-activated protein kinase (MAPK) inhibitors that in stromal cells from pediatric MDS and MDS-AML, p38MAPK was critical in serum-induced secretion of LIF. The serum induction of phosphorylated p38MAPK form was observed only in stromal cells from healthy children, whereas in MDS and MDS-AML basal levels were maintained suggesting constitutive p38MAPK activation. Our study suggested the possible importance in pediatric MDS of p38MAPK signaling pathway which may be a future therapeutic target.

All-trans retinoic acid inhibits the differentiation, maturation, and function of human monocyte-derived dendritic cells

2010-04-01

Abstract: All-trans retinoic acid (ATRA) affects on the function of antigen presenting cells with somewhat controversies. We investigated the effects of ATRA on differentiation, maturation and function of human monocyte-derived dendritic cells (DCs). Low dose (10−14M) or high dose (10−6M) of ATRA was added either when monocytes were differentiated into immature DCs (imDCs) or mature DCs (mDCs) were induced. Apoptotic cell populations were dramatically increased in imDCs or mDCs with increasing concentration of ATRA. The productions of IL-12p40 and IL-12p70 were significantly suppressed in imDCs or mDCs induced by the addition of ATRA in the dose-dependent manner, whereas IL-10 was increased. DCs cultured with ATRA induced the differentiation of naïve T cells towards a helper T cell type 2 (Th2) response and expansion of CD4+CD25+Foxp3+ regulatory T cells. Allostimulatory capacity of DCs was suppressed with increasing concentration of ATRA. These findings suggest that ATRA inhibits the effects on the differentiation, maturation and function of human monocyte-derived DCs in vitro and also enhance the differentiation of naïve T cell toward the Th2 type.

Multiple mechanisms induce ectopic expression of LYL1 in subsets of T-ALL cell lines

2010-04-01

Abstract: Basic helix–loop–helix (bHLH) transcription factors are essential for lymphocytic differentiation. Here, we have analyzed the complete bHLH family in T-cell acute lymphoblastic leukemia cell lines by expression profiling. Differential expression was detected for BHLHB2, HES1, HES4, HEY1, ID1, ID2, ID3, LYL1 and TAL1, highlighting dysregulation of family members with inhibitory activity. Subsequently we focused on the mechanisms responsible for aberrant expression of LYL1 in comparison to TAL1. Quantitative genomic PCR indicated microdeletions upstream of both, TAL1 and LYL1, targeting STIL/SIL and TRMT1, respectively. Additionally, one LYL1-expressing cell line exhibited amplification of TRMT1. While deletion of STIL correlated with expression of the STIL-TAL1 fusion transcript, no TRMT-LYL1 fusion transcripts were detected in parallel with genomic rearrangements thereof. Sequence analysis of the LYL1 promoter region revealed potential binding sites for transcription factors HOXA10, LMO2 and NKX2-5. Overexpression analysis, reporter gene assays and chromatin immuno-precipitation confirmed their activating impact on LYL1 expression. In conclusion, we identified multiple mechanisms which activate LYL1 in leukemic cells, including structural genomic alterations, namely microdeletion or amplification, together with the involvement of prominent oncogenic transcription factors.

Functional analyses of Src-like adaptor (SLA), a glucocorticoid-regulated gene in acute lymphoblastic leukemia

2010-04-01

Abstract: Glucocorticoids (GCs) cause apoptosis and cell cycle arrest in lymphoid cells and are used in the therapy of lymphoid malignancies. SLA (Src-like-adaptor), an inhibitor of T- and B-cell receptor signaling, is a promising candidate derived from expression profiling analyses in children with acute lymphoblastic leukemia (ALL). Over-expression and knock-down experiments in ALL in vitro model revealed that transgenic SLA alone had no effect on survival or cell cycle progression, nor did it affect sensitivity to, or kinetics of, GC-induced apoptosis. Although SLA is a prominent GC response gene, it does not seem to contribute to the anti-leukemic effects of GC.

Synergistic effect of inhibiting translation initiation in combination with cytotoxic agents in acute myelogenous leukemia cells

2010-04-01

Abstract: We have previously shown that inhibition of translation initiation, using the small molecule inhibitor silvestrol, induces apoptosis in a pre-clinical murine lymphoma model when combined with daunorubicin. Silvestrol blocks ribosome recruitment by targeting the RNA helicase, eIF4A, which is required for this process. Here we investigate the sensitivity of acute myelogenous leukemia (AML) cell lines to protein synthesis inhibition in combination with the standard cytotoxic agents daunorubicin, etoposide, and cytarabine. Silvestrol shows synergy with standard-of-care agents in AML cell lines and synergizes with ABT-737, a small molecule inhibitor of Bcl-XL and Bcl-2. The in vitro synergy between silvestrol and the cytotoxic drugs used in AML therapy provides a basis for in vivo evaluation of these combinations.

Chronic myeloid leukemia: A disease of youth in Brazil

2010-04-01

Chronic myeloid leukemia (CML) is usually an insidious disease and the median age at diagnosis is stated in Hematology text books to be around 50 years. In the past, patients seek medical attention as a consequence of symptoms of vigorous hematopoiesis (fever, sweats, bone pain, weight loss, and fatigue) or signs of extramedullary hematopoiesis (splenomegaly and left upper quadrant discomfort). However, current medical practice and the periodic routine medical evaluation resulted in shifts in clinicohematologic picture and it is becoming more common for patients to be diagnosed before the development of symptoms . Considering such shift, it was expected that average age at diagnosis could be younger. However, the age was significantly lower in interferon studies than in recent imatinib mesylate (IM) studies .

High body mass index is an independent predictor of differentiation syndrome in patients with acute promyelocytic leukemia

2010-04-01

Abstract: Increased BMI has been correlated to an increased incidence of APL, but not to the occurrence of differentiation syndrome (DS) in APL. We consecutively treated 39 APL patients with ATRA and idarubicin (according to PETHEMA regimen). Median age was 26 years. Forty-one percent patients were classified as intermediate risk, and 59% as high risk according to Sanz's score. Thirty-three patients (85%) reached CR. Eleven of the 36 patients evaluable for DS (30.5%) developed this syndrome (severe in 7 cases, moderate in 4, and fatal in 3 cases) within a median of 12 days (range 3–23) of ATRA onset. Six of the 9 (66.6%) patients with BMI≥30 developed DS vs. 5 of 27 (18.5%) with BMI<30 (p=0.012). Other predictors of DS in univariate analysis were: age≥40 year (p=0.033), baseline WBC≥20×109/l (p=0.003), and creatinine>1.4mg/dl (p=0.009). In multivariate analysis, BMI≥30 remained an independent predictor of DS in addition to baseline WBC≥20×109/l.

Primary mantle cell lymphoma of the thyroid

2010-04-01

Non-Hodgkin's lymphoma (NHL) incidence has rapidly increased since the 1970s. Incidence rates increased proportionally more for extranodal NHL than for nodal NHL . Primary NHL of the thyroid (PNHLT) is an uncommon diagnosis, accounting for 5% of all thyroid malignancies and 2% of primitive extranodal lymphomas, with an incidence of 0.5 per 100,000 population .

Corrigendum to “Prognostic significance of angiogenic/lymphangiogenic, anti-apoptotic, inflammatory and viral factors in 88 cases with diffuse large B cell lymphoma and review of the literature” [Leuk. Res. 33 (2009) 1627–1635]

Semra Paydas, Melek Ergin, Gulsah Seydaoglu, Seyda Erdogan, Sinan Yavuz — 2010-04-01

The authors regret that in the above-published paper the first word of the title was represented incorrectly. It is now represented correctly above.

Anti-angiogenic strategies will be a revolution in lymphoma?

Semra Paydas — 2010-04-01

I read with great interest the Open Forum published by Domenico Ribatti from Italy. He excellently presented the data about the lymphangiogenesis in tumor progression and cross-talk between VEGF-A and VEGF-C . Ribatti emphasized the anti-angiogenic strategies about the acute leukemias, myelodysplastic syndrome and multiple myeloma but not in lymphomas. Although in limited number, there are papers about lymphangiogenesis and angiogenesis in lymphomas . The largest series about VEGF-C expression in lymphomas was published by our group. Firstly we studied VEGF-C/VEGF-A expressions in 177 cases with lymphoma and then re-evaluated 88 cases with diffuse large B cell lymphoma subset . We found VEGF-C and VEGF-A expression in one third and two thirds of the cases, respectively and also found a good correlation with VEGF-A and VEGF-C expression. Overall survival was poorer in aggressive lymphoma cases with VEGF-C and/or VEGF-A expression but not in indolent lymphomas. Additionally cox regression analysis showed the VEGF-C and VEGF-A as the independent poor prognostic indicators. The strong association between angiogenesis and lymphangiogenesis, poor response to standard anti-lymphoma treatment and shorter survival in cases with VEGF-A/VEGF-C expression strictly suggest the potent anti-angiogenic strategy plus standard chemotherapy for these cases. With this approach clinical outcome will be better in aggressive and VEGF-A/VEGF-C expressing cases.

Paroxysmal nocturnal hemoglobinuria following alemtuzumab immunosuppressive therapy for myelodysplastic syndrome and complicated by recurrent life-threatening thrombosis despite anticoagulation: Successful intervention with eculizumab and fondaparinux

Kit L. Cheng, Judith Brody, Craig E. Warshall, Elaine M. Sloand, Steven L. Allen — 2010-04-01

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disease occurring in patients who have expansion of an abnormal hematopoietic clone characterized by mutations in the PIG A gene. This gene is necessary for the synthesis of an important protein anchor, glycosylphosphotidylinositol (GPI) . Although PIG A gene mutations are common and can be found in the general population, it is not well understood how some abnormal PIG A mutated clones are able to preferentially multiply and cause PNH . We report a case of a patient with myelodysplastic syndrome (MDS) who developed PNH following therapy with alemtuzumab and whose course was complicated by multiple recurrences of cerebral thrombosis despite anticoagulation.

Uterine chloroma, aortic thrombus and CALM/AF10 acute myeloid leukemia

2010-04-01

A 39-year-old woman presented a history of relapsed acute myeloid leukemia (AML) which allows the discussion of many aspects of clinical and biological features of AML. The initial diagnosis of acute leukemia was made in June 1993. At that time, the myelogram showed 98% undifferentiated peroxidase negative leukemic blasts cells. No tumoral syndrome was found at physical examination. Flow cytometry analysis of leukemic cells revealed an undifferentiated phenotype HLADR+CD7+CD38+ and negative for CD34, CD13, CD33, cMPO−, T and B cell markers. She was classified as AML0 according to the FAB classification which was the one used at this time. Cytogenetic analysis revealed a chromosomal translocation t(10,11) (p12;q21) associated with a trisomy 4. The patient obtained a complete remission after induction chemotherapy with cytarabine (Ara-C, 200mg/m2, d1–7) and daunorubicin (dnr, 60mg/m2, d1–3) further consolidated with a myeloablative bone marrow transplantation from a HLA-identical sibling (her brother) conditioned by total body irradiation (12Grays) and cyclophosphamide (60mg/kg d-2 and -1). The donor's and the patient's RBCs were type O, Rh-positive. CMV status was positive for the donor, negative for the patient.

Major molecular response achieved with dasatinib in a CML patient with F317L BCR-ABL kinase domain mutation

2010-04-01

Mutations of BCR-ABL tyrosine kinase domain represent the most frequently identified and best-studied mechanism of chronic myeloid leukemia (CML) resistance to the treatment with tyrosine kinase inhibitors (TKIs). Depending on the degree of in vitro sensitivity to TKIs and clinical experience, mutations resistant to all available TKIs (T315I) or to an individual TKI (F317L or V299L to dasatinib and F359V and P-loop mutations to nilotinib) have been described. In a recent issue of Blood, Jabbour et al. described 20 patients with CML who had developed F317L BCR-ABL kinase domain mutation during the treatment with imatinib or dasatinib. Although the authors found no difference in overall survival of patients with or without F317L mutation, the response to dasatinib in all patients with the mutation was invariably poor (partial or complete hematologic or cytogenetic responses were rare and transient) and prognosis of the patients was mostly dependent on the disease stage We describe a CML patient in chronic phase with F317L mutation who achieved and maintained a complete cytogenetic and a major molecular response on dasatinib treatment.

A thrombocytosis occurring in Philadelphia positive CML in molecular response to imatinib can reveal an underlying JAK2V617F myeloproliferative neoplasm

2010-04-01

Myeloproliferative neoplasms (MPN) such as primary myelofibrosis (PMF), polycythemia vera (PV) and essential thrombocytemia (ET) are clonal hematopoietic diseases which have been separated by definition from Philadelphia positive chronic myeloid leukemia (Ph+ CML). Recently, an acquired gain-of-function mutation (V617F) in the JAK2 gene has been discovered in the majority (up to 90%) of patients with PV and approximately half of the patients with PMF and ET . No JAK2V617F mutation was initially found in Ph+ CML, suggesting that JAK2 mutation and BCR-ABL rearrangement resulting from Ph translocation are mutually exclusive . More recently, several cases with the coexistence of BCR-ABL fusion gene and JAK2V617F mutation in blood and bone marrow samples were described . For these patients, JAK2V617F mutation either preceded the acquisition of BCR-ABL translocation or was revealed after effective treatment of Ph+ CML . We report here two new cases of JAK2V617F mutation discovered in Ph+ CML patients under imatinib treatment and compare our findings with those of similar reports.

First report of a medullar cord compression secondary to osseous plasmacytoma successfully treated with bortezomib and dexamethasone

2010-04-01

Abstract: Medullar cord compression secondary to osseous plasmacytomas affecting the vertebrae is an oncological emergency. A 75-year-old woman with recurrent osseous plasmacytomas and thoracic spinal cord compression, previously treated with radiotherapy, was successfully treated with bortezomib and dexamethasone. Three years later, when the plasmacytoma and spinal cord compression relapsed, she was retreated with the same therapeutic scheme, achieving a new complete clinical remission. This is the first reported case of an excellent response to the combination of bortezomib and dexamethasone for spinal cord compression due to osseous plasmacytoma.

A rare case of primary systemic amyloidosis of the neck with massive cervical lymph node involvement: A case report and review of the literature

2010-04-01

Abstract: Amyloidosis is a term applied to a diverse group of disorders that share the deposition of amyloid protein in various extracellular tissues. Systemic amyloidosis may involve almost any organ system in the body including regions in the head and neck; however, neck lymph node involvement is rare, with only five previous cases reported. We present the case of a primary systemic AL amyloidosis with hepatic, cervical, retroperitoneal, axillary and inguinal lymphnode localizations, unresponsive to medical therapy and treated with a surgical approach followed by autologous bone marrow transplantation. We review the pertinent literature with exclusive attention to the otorhinolaryngologic aspect.

Clonal evolution at leukemic relapse of multiple myeloma (secondary plasma cell leukemia) responding to re-treatment with bortezomib-based therapy. A case record

2010-04-01

Plasma cell leukemia (PCL) is an aggressive form of plasma cell proliferation which may both manifest as primary neoplasm (pPCL), or represent the evolution of a pre-existing multiple myeloma (MM), namely secondary plasma cell leukemia (sPCL), which is characterized by a very short median survival, ranging from 1.3 to 2 months .

Description of a new BCR-ABL point mutation in a CML patient with evolution to lymphoid blast crisis

2010-04-01

We identified for the first time a new BCR-ABL point mutation in a CML patient that developed disease progression to lymphoid blast crisis. Here, we describe the clinical and molecular features of this imatinib-resistant CML patient.

Primary non-Hodgkin lymphoma of cervix successfully treated with rituximab: Positron emission tomography images before and after therapy: A case report

2010-04-01

Primary non-Hodgkin's lymphoma (NHL) of the genital tract is extremely rare (0.5%) and mostly originates from the ovary . The cervix lymphoma is 0.008% of the all cervix tumors and 2% of the all extranodal lymphomas in the females . The most common histological type is diffused large B cell lymphoma (DLBCL) . Primary cervical carcinoma, sarcoma or benign inflammatory conditions are kept in mind in differential diagnosis . Histopathological and immunohistochemical examinations of cervix biopsy specimen are required for definitive diagnosis . In staging, computerized tomography (CT) of the pelvis, abdomen and thorax or position emission tomography (PET–CT) can be used. There is not any established treatment protocol for primary cervix lymphoma (PCL) due to rarity of disease. Radiotherapy (RT), chemotherapy, immunotherapy, surgery, either alone or in combination can be applied . Herein we report a case of PCL that was staged and re-evaluated after treatment by using PET–CT. The patient was treated successfully with combination of R-CHOP (Rituximab, cyclophophamide, doxorubucin, vincristine, prednisone) and RT.

Allogenic bone marrow transplantation with fludarabine/busulfan16 conditioning regimen and dasatinib maintenance therapy for elderly Philadelphia-positive acute/advanced leukemia patients

2010-04-01

Therapeutic outcome of chronic myelogenous leukemia (CML) in advanced phases and of Philadelphia chromosome-positive (Ph+) acute leukemias remains dismal, even with tyrosine kinase inhibitors (TKIs) against Bcr-Abl or hematopoietic stem cell transplantation (HSCT) with maximally myeloablative conditioning (MAST). Especially, because patients over 55 years old are not eligible for MAST, the establishment of a treatment strategy for elderly patients with acute/advanced Ph+ leukemias has long been anticipated. We here present our experience with the use of fludarabine (Flu)/busulfan (Bu) 16 conditioning regimen (FB16) and dasatinib maintenance therapy following allogenic bone marrow transplantation (BMT) for two elderly patients with Ph+ acute/advanced leukemia.

Isolated CNS relapse of CML after bone marrow transplantation

Anish Thomas, Constance K. Stein, Teresa C. Gentile, Chirag M. Shah — 2010-04-01

Isolated extramedullary relapse (EMR) of chronic myelogenous leukemia (CML) after bone marrow transplantation (BMT) is rare, seen in only 0.21% of cases . EMR in the central nervous system (CNS) is a rare event, and when seen is more commonly associated with lymphoblastic cells . Only two cases of CNS myeloblastic relapse have been reported previously . To our knowledge, isolated CNS myeloid blastic crisis after allogenic BMT for CML has previously not been reported.

Chronic lymphocytic leukemia presenting with symptomatic peritoneal infiltration

2010-04-01

Organ infiltration by leukemic cells in patients with B-cell chronic lymphocytic leukemia (CLL) is often asymptomatic, but is frequently detected during an autopsy. CLL cells usually traffic to organs of the hematopoietic system, and only in end-stage disease to non-hematopoietic organs. However, patients with early stage CLL and infiltration into the pituitary gland, myocardium, thyroid, lung, kidney, gall bladder, and prostate have been reported. Clinical manifestations due to gastrointestinal infiltration have rarely been described. We report the very rare case of CLL diagnosis in a patient suffering from epigastralgia due to peritoneal infiltration.

Littoral cell angioma: A correctable cause of progressive pancytopenia in a patient with myelodysplastic syndrome

2010-04-01

Myelodysplastic syndromes (MDS) are clonal bone marrow disorders characterized by cytopenias in the setting of a cellular bone marrow with morphologic dysplasia . In establishing the diagnosis of MDS, it is important to evaluate for other causes of cytopenias. Similarly, when cytopenias worsen in patients with MDS, it is important to reevaluate for other causes of cytopenias. We report a patient with MDS whose pancytopenia was exacerbated by a concurrent littoral cell angioma (LCA), a rare primary vascular tumor arising from the littoral cells of the spleen , and whose blood counts improved substantially following laparoscopic splenectomy. We also review previously published LCA cases, including previous reports of association with hematopoietic stem cell disorders.

Multiple lipoma with hyperlipidemia in a multiple myeloma patient treated with bortezomib/dexamethazone

Moritaka Gotoh, Toshihiko Kitahara, Juri Sakuta, Daigo Akahane, Kazuma Ohyashiki — 2010-04-01

Bortezomib (Bercade®) is a proteasome inhibitor, that inhibits the ubiquitin pathway to enter clinical studies . This pathway controls the activation of nuclear factor-kappa B (NF-κB; a major transcription factor) by regulating degradation of the NF-κB inhibitor (I-κB). In cancer, dysregulation of this catalytic process may contribute to tumor progression, drug resistance, and altered immune surveillance. Thus, any inhibition of the proteasome system creates an imbalance of various regulatory proteins, triggering cell cycle arrest in the G1/S and G2/M phases of the cell cycle and in the apoptotic pathways within the cell. The anti-tumor effects of bortezomib are a result of cell cycle arrest and apoptosis or autophagy, resulting from the effects of proteasome inhibition . The underlying mechanisms include NF-κB inhibition, upregulation of various apoptotic pathways, and effects on the tumor microenvironment. These consequences of proteasome inhibition have been well studied in the context of multiple myeloma (MM), where it is now increasingly apparent that the malignant cell and its microenvironment are both important targets for MM therapy. However, the mechanism of adverse events related to bortezomib-treatment is not fully determined. We are the first to report a case of MM in which hyperlipidemia and lipoma arose after successful bortezomib-treatment.