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1.  Grb2-associated binding (Gab) proteins in hematopoietic and immune cell biology 
Grb2-associated binding (Gab) scaffolding/adapter proteins are a family of three members including mammalian Gab1, Gab2, and Gab3 that are highly conserved. Since the discovery of these proteins, there has been an extensive amount of work done to better understand Gab functional roles in multiple signaling pathways, typically acting as a downstream effectors of receptor-tyrosine kinase (RTK)-triggered signal transduction. In addition to their participation in hematopoiesis, Gabs play important roles in regulation of immune response and in also in cancer cell signaling. Gabs may play complex roles and thus a complete understanding of their interactions and how they modulate hematopoietic and immune cell biology remains to be determined. This review will cover the most recent findings including the involvement of Gabs in disease development and signaling which will be important for design of future therapeutic interventions.
PMCID: PMC3232456  PMID: 22163099
Adapter protein; cytokine signaling; Grb2-associated binding protein; Gab; receptor tyrosine kinase; cancer signaling
2.  Therapeutic monoclonal antibodies for multiple myeloma: an update and future perspectives 
Multiple myeloma (MM) still remains incurable in most of the patients. Despite of treatments with high-dose chemotherapy, stem cell transplantation and other novel therapies, most patients will become refractory to the therapies and relapse. Thus, it is urgent to develop new approaches for MM treatment. Currently, antibody-targeted therapy has been extensively utilized in hematological malignancies, including MM. Several novel monoclonal antibodies (mAbs) against MM have been generated and developed over the past several years. These mAbs aim to target not only tumor cells alone but also tumor microenvironment, including interaction of tumor-bone marrow stromal cells and the components of bone marrow milieu, such as cytokines or chemokines that support myeloma cell growth and survival. These include mAbs specific for CD38, CS1, CD40, CD74, CD70, HM1.24, interleukin-6 and β2-microglobulin (β2M). We have shown that anti-β2M mAbs may be a potential antitumor agent for MM therapy due to their remarkable efficacy to induce myeloma cell apoptosis in tumor cell lines and primary myeloma cells from patients in vitro and in established myeloma mouse models. In this article, we will review advances in the development and mechanisms of MM-targeted mAbs and especially, anti-β2M mAbs. We will also discuss the potential application of the mAbs as therapeutic agents to treat MM.
PMCID: PMC3207269  PMID: 22065141
Multiple myeloma; monoclonal antibodies; anti-β2M mAbs; therapy
3.  C-MOPP: the forgotten regimen plus Rituximab for untreated and relapsed follicular lymphoma 
C-MOPP is a chemotherapy regimen for the treatment of Non-Hodgkin lymphoma (NHL). Because rituximab improves results in B-cell NHL, we added rituximab to C-MOPP, giving it the term C-MOPP-R. We retrospectively report the results of C-MOPP-R treatment for follicular lymphoma at Saint Louis University Cancer Center from 2000-2009. Treatment response was assessed with fusion PET/CT using International Harmonization Project Criteria and toxicity using National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0. Thirty-seven patients with follicular lymphoma were treated at our institution with C-MOPP-R. The complete response rate was ninety-four percent and sixty-eight percent in untreated and relapsed patients, respectively. The median progression-free and overall survivals were not reached with median observation time of 34 months. Development of peripheral neuropathy required truncation of planned vincristine dosing in nearly half of patients. We believe that C-MOPP-R results in excellent response rates, progression-free, and overall survival for untreated and relapsed follicular lymphoma and capped vincristine dosing is essential to optimize safety.
PMCID: PMC3301422  PMID: 22432081
Lymphoma; Non-Hodgkin; Positron Emission Tomography; antibodies; monoclonal; antineoplastic agents
4.  Novel treatment paradigm for elderly patients with multiple myeloma 
The treatment of multiple myeloma has undergone important changes in the last few years. The use of novel agents, such as the immunomodulatory drugs thalidomide and lenalidomide, and the proteasome inhibitor bortezomib, has increased the treatment options available and significantly improved the outcome of this rare disease. Several trials have shown the advantages linked to the use of novel agents both in young patients, who are considered eligible for transplantation, and elderly patients, who are considered transplant ineligible. In the non-transplant setting, novel agent-containing regimens have replaced the traditional melphalan-prednisone approach. Preliminary data also support the role of consolidation and maintenance therapy to further improve outcomes. An appropriate management of side effects is fundamental for the success of the treatment, and outcome should always be balanced against the toxicity profile associated with the regimen used. This review provides an overview of the latest strategies including novel agents used to treat elderly patients with multiple myeloma.
PMCID: PMC3301431  PMID: 22432080
Multiple myeloma; elderly patients; new drugs; thalidomide; lenalidomide; bortezomib
5.  Use of IGK gene rearrangement analysis for clonality assessment of lymphoid malignancies: a single center experience 
Diagnosis of B-non Hodgkin lymphomas (NHLs) is based on clinical, morphological and immunohistochemi-cal features. However, in up to 10-15% of cases, analysis of immunoglobulin heavy (IGH) or light (IGK/IGL) chains genes is required to discriminate between malignant and reactive lymphoid proliferations. In this study, we evaluated the feasibility and efficiency of IGK analysis in the routine diagnostic of B-cell lymphoproliferative disorders (B-LD) when applied to formalin-fixed paraffin-embedded (FFPE) tissues. Clonality patterns were studied in 59 B-LD using the BIOMED-2 protocol for IGK assays, after failure of the IGH assay. PCR products were evaluated by both heterodu-plex and GeneScan analysis. IGK analysis was technically successful in all cases. Overall, it supported the histopa-thological suspicion in 52/59 cases (88%), the sensitivity and specificity being 83% and 80%, respectively. Further, positive and negative predictive values were 95% and 50%, respectively. Interestingly, among various lymphoma subtypes, marginal zone lymphoma and follicular lymphoma most frequently required IGK analysis. In conclusion, IGK study according to the BIOMED-2 protocol resulted feasible and extremely useful in supporting challenging diagnosis of B-LD even if applied on FFPE samples. Accordingly, when NHL is suspected, negative results at IGH analysis should not be considered as conclusive and further investigation of IGK is appropriate.
PMCID: PMC3301430  PMID: 22432078
BIOMED-2; molecular diagnostic; IGK; non Hodgkin lymphoma; PCR
6.  A review of anemia as a cardiovascular risk factor in patients with myelodysplastic syndromes 
Background: Anemia is an important cause of morbidity in MDS patients, principally through increased cardiovascular disease. Transfusion status has been seen to be a significant prognostic factor for disease progression and mortality, yet the relationship between anemia levels and cardiovascular disease is not well understood. Objective: This study aimed to review the published literature on the effect of anemia on cardiovascular outcomes in patients with MDS. Methods: A systematic literature review was undertaken to identify studies that investigated the relationship between anemia (as defined by hemoglobin levels) and cardiovascular outcomes in patients with MDS (all subtypes). Results: Three studies were identified that explicitly evaluated the relationship between anemia and cardiovascular outcomes in MDS, and another study reported the relationship between hemoglobin levels and survival. The four studies consistently showed a strong relationship between lower hemoglobin levels and worse cardiovascular outcomes, including cardiac remodeling, congestive heart failure, coronary artery disease, myocardial infarction, arrhythmia, heart valve disease, and cardiovascular mortality. Anemia was seen to be an independent predictor of cardiovascular disease outcomes in patients with MDS, beyond transfusion status and IPSS. Conclusion: Based upon a relatively small body of evidence, there appears to be a strong and clinically significant association between anemia and cardiovascular morbidity and mortality in MDS. While further research is needed, clinicians should seek to actively manage hemoglobin levels in MDS patients before the point of transfusion dependency is reached.
PMCID: PMC3301424  PMID: 22432077
Myelodysplastic syndromes; MDS; anemia; cardiovascular disease; mortality; quality of life; hemoglobin; transfusion
7.  Treatment of FLT3-ITD acute myeloid leukemia 
Acute myeloid leukemia (AML) is an aggressive hematologic malignancy which is cured in a minority of patients. A FLT3-internal tandem duplication (ITD) mutation, found in approximately a quarter of patients with de novo AML, imparts a particularly poor prognosis. Patients with FLT3-ITD AML often present with more aggressive disease and have a significantly higher propensity for relapse after remission. The therapeutic approach for these patients has traditionally included intensive induction chemotherapy, followed by consolidative chemotherapy or hematopoietic cell transplantation (HCT). In recent years, multiple small molecule inhibitors of the FLT3 tyrosine kinase have been studied preclinically and in clinical trials. The earlier generation of these agents, often non-specific and impacting a variety of tyrosine kinases, produced at best transient peripheral blood responses in early clinical trials. Additionally, the combination of FLT3 inhibitors with cytotoxic regimens has not, as of yet, demonstrated an improvement in overall survival. Nevertheless, multiple current trials, including those with sorafenib, lestaurtinib, and midostaurin, continue to study the combination of FLT3 inhibitors with standard chemotherapy. Factors such as sustained FLT3 inhibition, protein binding, pharmacokinetics, and the presence of elevated FLT3-ligand levels appear to significantly impact the potency of these agents in vivo. In recent years, the development of more specific and potent agents has generated hope that FLT3 inhibitors may play a more prominent role in the treatment of FLT3-ITD AML in the near future. Nevertheless, questions remain regarding the optimal timing and schedule for incorporation of FLT3 inhibitors. The suitability, type, and timing of allogeneic HCT in the therapeutic approach for these patients are also issues which require further study and definition. Recent retrospective data appears to support the efficacy of allogeneic HCT in first complete remission, possibly due to a graft versus leukemia effect. However, larger prospective studies are necessary to further elucidate the role of HCT and its potential combination with FLT3 inhibitor therapy. We are hopeful that current clinical investigation will lead to an optimization and improvement of outcomes for these patients.
PMCID: PMC3301423  PMID: 22432079
8.  Epstein-Barr virus-positive diffuse large B-cell lymphoma of the elderly expresses EBNA3A with conserved CD8+ T-cell epitopes 
Post-transplantation lymphoproliferative disorders (PTLD) arise in the immunosuppressed and are frequently Epstein-Barr virus (EBV) associated. The most common PTLD histological sub-type is diffuse large B-cell lymphoma (EBV+DLBCL-PTLD). Restoration of EBV-specific T-cell immunity can induce EBV+DLBCL-PTLD regression. The most frequent B-cell lymphoma in the immunocompetent is also DLBCL. ‘EBV-positive DLBCL of the elderly’ (EBV+DLBCL) is a rare but well-recognized DLBCL entity that occurs in the overtly immunocompetent, that has an adverse outcome relative to EBV-negative DLBCL. Unlike PTLD (which is classified as viral latency III), literature suggests EBV+DLBCL is typically latency II, i.e. expression is limited to the immuno-subdominant EBNA1, LMP1 and LMP2 EBV-proteins. If correct, this would be a major impediment for T-cell immunotherapeutic strategies. Unexpectedly we observed EBV+DLBCL-PTLD and EBV+DLBCL both shared features consistent with type III EBV-latency, including expression of the immuno-dominant EBNA3A protein. Extensive analysis showed frequent polymorphisms in EB-NA1 and LMP1 functionally defined CD8+ T-cell epitope encoding regions, whereas EBNA3A polymorphisms were very rare making this an attractive immunotherapy target. As with EBV+DLBCL-PTLD, the antigen presenting machinery within lymphomatous nodes was intact. EBV+DLBCL express EBNA3A suggesting it is amenable to immunotherapeutic strategies.
PMCID: PMC3301425  PMID: 22432076
Epstein-Barr virus; diffuse large B-cell lymphoma; EBNA3A; T-cell; epitope; immunotherapy; posttransplantation lymphoproliferative disorder
9.  Progress in myeloma stem cells 
Multiple myeloma (MM) is the second most common hematologic malignancy in the United States and affects about 4 in 100,000 Americans. Even though much progress has been made in MM therapy, MM remains an incurable disease for the vast majority of patients. The existence of MM stem cell is considered one of the major causes of MM drug-resistance, leading to relapse. This highlights the importance and urgency of developing approaches to target MM stem cells. However, very little is known about the molecular characteristics of the MM stem cells, which makes it difficult to target MM stem cells therapeutically. Evidence of the existence of a myeloma stem cell has been provided by Matsui et al. showing that the CD138- and CD20+ fraction, which is a minor population of the MM cells, has a greater clonogenic potential and has the phenotype of a memory B-cell (CD19+, CD27+). In this review, we report recent progress of cell surface markers in cancer stem cells, especially in myeloma and the molecular mechanisms related to drug resistance and myeloma disease progression.
PMCID: PMC3301427  PMID: 22432075
Cancer stem cell; multiple myeloma; drug resistance; and cell signaling
10.  Galectins in hematological malignancies 
Carbohydrates are traditionally considered to be an important source of energy for living organisms. In the field of biology, they are defined as organic compounds composed of carbon, hydrogen, and oxygen that are organized into ring structures. The analysis of these structures and their functions has led to a new field of biology called “glycobiology.” In the biomedical sciences, glycobiology is rapidly emerging to be an integral part of complex biological processes. Changes in glycan structures and the interactions of these structures with endogenous carbohydrate-binding proteins, known as lectins, are now considered to be potential biomarkers on cancer cells for monitoring tumor progression. Evidence suggesting that the interactions between lectins and their ligands have a major role in the different steps of cancer progression has accumulated at a rapid pace and has gained the attention of several oncologists. This is particularly true for galectin family members because changes in their expression levels correlate with alterations in cancer cell growth, apoptosis, and cell-cell and cell-matrix interactions. Here we provide an integrated view of the role of galectins in hematological malignancies.
PMCID: PMC3301428  PMID: 22432074
galectins; lymphoma; apoptosis; gene profiling; immunosuppression
11.  Visualization of immune response kinetics in full allogeneic chimeras 
Background: Donor Lymphocyte Infusion (DLI) is a well-recognized tool for augmentation of the anti-leukemia effect after mismatched bone marrow transplantation. Experimental results show, however, that DLI efficacy is strongly dependent on the number of donor hematopoietic cells persisting in recipient after transplantation. It is strong in mixed chimeras and relatively weak in full chimeras (FC) that replace host antigen-presenting cells by donor antigen-presenting cells. In this study we applied a new in vivo cytotoxicity monitoring method for evaluation of the changes in FC anti-host immunity after co-transplantation of donor and host hematopoietic cells together. Method: Full hematopoietic chimeras and naïve control mice were transplanted with a mixture of equivalent numbers of donor and recipient or donor and third party splenocytes labeled by a cell-permeable fluorescent dye CFDA-SE. The animals were sacrificed at various time points, and their splenocyte suspensions were prepared, depleted of red blood cells, stained with allophycocyanin-labeled anti-H2b antibodies, and analyzed using fluorescence-activated cell sorting. The immune response was assessed according to the percentage of single positive CFDA-SE+/ H2b- cells of all CFDA-SE+ cells. Results: FC grafted with splenocytes from similar FC mixed with splenocytes from naïve host-type or third-party-type mice rejected host cells within 14 days, and third-party cells within 7 days. NK cell depletion in vivo had no influence on host cell rejection kinetics. Co-infusion of host-type splenocytes with splenocytes obtained from naïve donor-type mice resulted in significant acceleration of host cell rejection (10 days). Naïve mice rejected the same amount of allogeneic lymphocytes within 3 days. Conclusions: Proposed method provides a simple and sensitive tool to evaluate in vivo post-transplant cytotoxicity in different experimental settings. The method demonstrates that FC is specifically deficient in their ability to reject host lymphocytes even when antigen-presenting host cells are provided. DLI improve anti-host immune response in FC but can not restore it to the level observed in naïve donor-type mice.
PMCID: PMC3301426  PMID: 22432073
transplantation; chimerism; immune response; leukemia; donor lymphocyte infusion
12.  Grb2-associated binding (Gab) proteins in hematopoietic and immune cell biology 
Grb2-associated binding (Gab) scaffolding/adapter proteins are a family of three members including mammalian Gab1, Gab2, and Gab3 that are highly conserved. Since the discovery of these proteins, there has been an extensive amount of work done to better understand Gab functional roles in multiple signaling pathways, typically acting as a downstream effectors of receptor-tyrosine kinase (RTK)-triggered signal transduction. In addition to their participation in hematopoiesis, Gabs play important roles in regulation of immune response and in also in cancer cell signaling. Gabs may play complex roles and thus a complete understanding of their interactions and how they modulate hematopoietic and immune cell biology remains to be determined. This review will cover the most recent findings including the involvement of Gabs in disease development and signaling which will be important for design of future therapeutic interventions.
PMCID: PMC3232456  PMID: 22163099
Adapter protein; cytokine signaling; Grb2-associated binding protein; Gab; receptor tyrosine kinase; cancer signaling
15.  Bone marrow angiogenesis and progression in multiple myeloma 
Multiple myeloma plasma cells home and expand in the bone marrow where cause an unbalanced bone remodelling with increased bone resorption and low bone formation that represent the typical feature in the majority of patients. A clinically relevant aspect of the interactions of multiple myeloma plasma cells in the bone marrow microenvironment is neovascularization, a constant hallmark of disease progression. This process is only partially supported by factors such as vascular endothelial growth factor, fibroblast growth factor-2 and metalloproteinases, which are directly secreted by the tumor cells. In fact, the presence in the bone marrow microenvironment of cytokines, in particular interleukin-6, as a consequence of plasma cell-stromal cell interactions, induces the production and secretion of angiogenic factors by other cells present in the bone microenvironment, thus contributing to the angiogenic switch during the progression of the disease. Near angiogenesis vasculogenesis occur in the bone marrow of myeloma patients and contribute to the vascular three formation. In the bone marrow of myeloma patients haematopoietic stem cells are recruited and induced to differentiate into endothelial cells by the angiogenic cytokines present in the microenvironment. Myeloma plasma cells also induce angiogenesis indirectly via recruitment and activation of stromal inflammatory cells (i.e.: macrophages and mast cells) to secrete their own angiogenic factors. They are recruited and activated by tumor plasma cells through the secretion of fibroblast growth factor-2, interleukin-8, and other chemokines, such as ITAC, Mig, IP-10. When macrophages and mast cells are activated they secrete their angiogenic factors: fibroblast growth factor-2, vascular endothelial growth factor, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, which contribute to enhance the tumor neovascularization. Finally, myeloma macrophages when exposed to vascular endothelial growth factor and fibroblast growth factor-2 secreted by plasma cells shows vasculogenic ability and acquire endothelial cell markers and transform into cells functionally and phenotypically similar to paired bone marrow endothelial cells. So they participate to the formation of the bone marrow capillary network (vasculogenic mimicry).
PMCID: PMC3301416  PMID: 22432068
Angiogenesis; endothelial cells; fibroblast growth factor-2; multiple myeloma; tumor progression; vasculogenesis; vascular endothelial growth factor
16.  Mouse models as tools to understand and study BCR-ABL1 diseases 
Mouse models of human malignancy have greatly enhanced our understanding of disease pathophysiology and have led to novel therapeutic approaches, some with extraordinary success, one such example being inhibition of the BCR-ABL1 oncogene in chronic myeloid leukaemia (CML). Here, we review aspects of the biology of CML that have been uncovered at least in part through the generation and analysis of retroviral and transgenic mouse models of BCR-ABL1 disease. It can be expected that these models will also serve as important tools in the future, especially in the rational design of strategies to eradicate leukemic stem cells and potentially cure CML as well as other cancers.
PMCID: PMC3301413  PMID: 22432067
BCR-ABL1; mouse models; retroviral; transgenic; leukemic stem cells; hematopoietic stem cells
17.  Infectious complications in cord blood and T-cell depleted haploidentical stem cell transplantation 
Infections due to post transplant immune deficiency is a major problem following allogeneic stem cell transplantation, particularly in patients receiving cord blood or T-cell depleted haploidentical transplants. We evaluated the incidence and type of infectious complications that occurred in these two types of transplant for 65 patients, 37 cord blood and 28 haploidentical, who received the same conditioning regimen: fludarabine, melphalan and thiotepa. While incidence of infections appeared similar in both types of transplant, viral infections were more frequent than bacterial or fungal infections and were the most common cause of death in both groups. Patients in the haploidentical group were 1.7 times (95% CI: 1.1 to 2.5) more likely to have a viral infection (p=0.013). Bacterial, fungal and CMV infections still quite frequent but contributed less to mortality. Pneumonia was the most common clinical syndrome and the number one cause of death in both groups. Both pneumonia and bacteremia occurred within the first 100 days in the majority of HSCT patients while CBT patients had a bimodal distribution, with more than one third of episodes after 6 months post transplant.
PMCID: PMC3301419  PMID: 22432070
Infectious complications; cord blood transplantation; T-cell depleted haploidentical stem cell transplantation
18.  The evolving role of statins in hematopoietic stem and progenitor cell transplantation 
Allogeneic hematopoietic stem cell transplantation is the sole curative modality for a variety of malignant and benign hematological disorders. Despite advances in supportive care and transplant conditioning regimens graft-versus-host disease (GVHD), infectious complications and end organ toxicity remain the leading causes of transplant related mortality (TRM). Development of safe and effective strategies to mitigate these significant complications associated with HSCT, are urgently needed. Statins are lipid lowering drugs, which reduce cholesterol production by inhibiting HMG-CoA reductase, with a well defined toxicity profile. Statins have pleiotropic immunomodulatory effects which are relevant in the context of treating and preventing GVHD. In addition to GVHD statins may possess several other effects that might have clinical benefit in the setting of hematopoietic cell transplantation, such as treatment of bronchiolitis obliterans and antineoplastic activity. Herein we review the emerging role of statins in improving the outcomes of patients undergoing HSCT.
PMCID: PMC3301410  PMID: 22432066
Statin; atorvastatin; GVHD; HMG-CoA reductase inhibitors; allogeneic stem cell transplantation; multiple myeloma; idiopathic pulmonary fibrosis; graft-versus-host disease
19.  Hematopoietic stem cell transplantation in China: current status and prospects 
During the past four decades, a substantial progress has been made in the field of hematopoietic stem cell transplantation (HSCT). From July, 2007 to December, 2010, a transplant survey from 42 HSCT units indicates that the types of transplantation performed are related identical (43%), related mismatched/haploidentical (28%), unrelated donor matched (11%), unrelated donor mismatched (7%), umbilical cord blood (UCB, 2%) and autologous (9%). The distribution of disease entities being transplanted in allogeneic settings is acute myeloid leukemia (AML) (34%), acute lymphoblastic leukemia(ALL) (24%), chronic myeloid leukemia (CML) (20%), myelodysplastic syndrome (MDS) (8%), aplastic anemia (AA) (7%), Mediterranean anemia (MIA) (2%), non-Hodgkin's lymphoma (NHL) (3%), and other diseases (3%). Clinical data from Peking University Institute of Hematology and other transplant centers suggest that haploidentical transplantation has been a choice of the best alternative source of stem cells for individual patients without matched sibling donors. A modified donor lymphocyte infusion (DLI) approach can be safely used for prophylaxis and treatment of leukemia relapse in patients with advanced leukemia following mismatched transplant. The number of transplants from unrelated donor or related mismatched/haploidentical donor has increased significantly during recent years. Double UCBT is a promising strategy for the therapy of hematological disease. In addition, mesenchymal stem cell (MSC) transplantation may be a potential therapeutic approach for treating systemic lupus erythematosus (SLE).
PMCID: PMC3301412  PMID: 22432069
Hematopoietic; blood; stem cell; transplantation; HSCT; China; review
20.  The ubiquitin-proteasomal system is critical for multiple myeloma: implications in drug discovery 
Bortezomib is a specific inhibitor of proteasomes, the most important protease complexes in protein degradation. Bortezomib can induce apoptosis of a variety of cancer cells, including leukemia, lymphoma, multiple myeloma, breast cancers, prostate cancers, lung cancers, and so on. However, extensive studies and overall evaluation suggested that multiple myeloma is the most sensitive and the best responsive disease which was later approved by Food and Drug Administration for bortezomib treatment. Because proteasomes are an essential component in the ubiquitin-proteasomal protein degradation pathway, the discovery of bortezomib implicates that the UPS is critical for myeloma pathophysiology. The UPS also contains ubiquitin, ubiquitin-activating enzymes (E1), ubiquitin-conjugating enzymes (E2), ubiquitin ligases (E3) and deubiquitinases (Dubs). In this review, we examined and analyzed the recent advancements of the UPS components in multiple myeloma and its implications in drug discovery for myeloma treatment.
PMCID: PMC3301411  PMID: 22432065
Ubiquitin-proteasomal system; deubiquitinases; bortezomib; multiple myeloma; drug discovery
21.  Molecular mechanisms influencing NK cell development: implications for NK cell malignancies 
Natural Killer (NK) cells are important effector cells in both the innate and adaptive immune responses. Although they were identified almost 40 years ago, our understanding of how and where NK cells develop is rudimentary. In particular, we have only a limited understanding of the signaling pathways that need to be activated to cause NK cell commitment and maturation. Knowledge of this process is important as disruptions can lead to the development of highly aggressive NK cell malignancies. In this review, we discuss the known molecular mechanisms that trigger NK cell commitment, prompt them to mature and finally allow them to become functional killers. Known disruptions in this developmental process, and how they may contribute to malignancy, are also addressed.
PMCID: PMC3301417  PMID: 22432064
Animal; human; Natural Killer cell; transcription factors; cytokines; cell differentiation; lymphopoiesis; gene expression regulation; lymphoma
22.  Therapeutic monoclonal antibodies for multiple myeloma: an update and future perspectives 
Multiple myeloma (MM) still remains incurable in most of the patients. Despite of treatments with high-dose chemotherapy, stem cell transplantation and other novel therapies, most patients will become refractory to the therapies and relapse. Thus, it is urgent to develop new approaches for MM treatment. Currently, antibody-targeted therapy has been extensively utilized in hematological malignancies, including MM. Several novel monoclonal antibodies (mAbs) against MM have been generated and developed over the past several years. These mAbs aim to target not only tumor cells alone but also tumor microenvironment, including interaction of tumor-bone marrow stromal cells and the components of bone marrow milieu, such as cytokines or chemokines that support myeloma cell growth and survival. These include mAbs specific for CD38, CS1, CD40, CD74, CD70, HM1.24, interleukin-6 and β2-microglobulin (β2M). We have shown that anti-β2M mAbs may be a potential antitumor agent for MM therapy due to their remarkable efficacy to induce myeloma cell apoptosis in tumor cell lines and primary myeloma cells from patients in vitro and in established myeloma mouse models. In this article, we will review advances in the development and mechanisms of MM-targeted mAbs and especially, anti-β2M mAbs. We will also discuss the potential application of the mAbs as therapeutic agents to treat MM.
PMCID: PMC3207269  PMID: 22065141
Multiple myeloma; monoclonal antibodies; anti-β2M mAbs; therapy
23.  Specific chromosomal IG translocations have different prognoses in chronic lymphocytic leukemia 
Background
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).
Designs and methods
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).
Results
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).
Conclusions
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.
PMCID: PMC3301415  PMID: 22432063
Chronic lymphocytic leukemia; IGH; BCL2; chromosomal translocation
24.  Premature transcript termination, trans-splicing and DNA repair: a vicious path to cancer 
So far, about 800 different chromosomal translocations have been characterized in hemato-malignant and solid tumors. Chromosomal translocations mostly result in the expression of chimeric fusion proteins associated with enhanced proliferation and/or malignant transformation. Here, we demonstrate that genes frequently involved in such genetic rearrangements exhibit a unique feature: premature transcriptional termination. These early-terminated RNA molecules have an abundance of 10-20% when compared to their cognate full-length transcripts. They exhibit an unsaturated splice donor site that gives rise to trans-splicing events, leading to RNAs displaying exon repetitions or chimeric fusion RNAs. These arbitrary fusion RNAs mimic the presence of a chromosomal translocation in genetically unaffected cells. Based on our and published data, we propose the hypothesis that these artificial “chimeric fusion transcripts” may influence DNA repair processes, resulting in the generation of de novo chromosomal translocations. This idea provides a rational explanation why different individuals suffer from nearly identical genetic rearrangements.
PMCID: PMC3301421  PMID: 22432062
Acute leukemia; chromosomal translocations; early-terminated transcripts; transsplicing; DNA repair; RNA-templated DNA repair

Results 1-24 (24)