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In monoclonal gammopathies (MG) and multiple myeloma (MM), normal natural cytotoxicity receptors (NCR) expression (NCR1/NKp46, NCR2/NKp44, NCR3/NKp30) is observed in natural killer (NK) cells. Nonetheless, except in plasma cell leukemia, few tumor plasmocytes are present in PB, while NK studies have been performed on peripheral blood (PB). For this reason we focused our attention on NK from bone marrow (BM). Our study demonstrates that the down-regulation of NCR3/NKp30 is only detectable in NK from BM but not in PB, and shows a drastic decrease of both NKG2D and CD244/2B4/p38 expression in NK from BM in comparison with PB. In conclusion, our data more precisely describe the mechanism of immune escape of MG/MM from innate immunity since we show a drastic down regulation of 3 major activating NK receptors (NCR3/NKp30, NKG2D and CD244/2B4/p38) at the site of tumor, i.e BM, that was undetectable in PB. Further studies regarding immune regulatory drugs in MG/MM will imperiously require the assessment of immune cell status not only in PB but also in BM to obtain more relevant data regarding anti-tumor efficacy.

Hepatitis C virus (HCV) infection is frequent among HIV-infected patients. We describe, the characteristics of 6 HIV/HCV-coinfected patients with B-cell non-Hodgkin lymphoma (NHL) included in a prospective cohort study of HIV-related lymphomas. Five of the 6 cases had features of marginal zone/lymphoplasmacytic NHL versus 1 of 33 HIV only-infected patients. Remarkably, anti-HCV treatment led to a hematological response in a patient with splenic marginal zone lymphoma. This supports the role of chronic antigenic stimulation by HCV on lymphomagenesis and further evaluation of HCV antiviral therapy in coinfected patients with NHL.

The vast majority of patients with acute myeloid leukemia (AML) achieve complete remission (CR) after standard induction chemotherapy. However, the majority subsequently relapse and die of the disease. A leukemia stem cell (LSC) paradigm has been invoked to explain this failure of CR to reliably translate into cure. Indeed, LSCs are highly enriched in CD34+CD38− leukemic cells that exhibit positive aldehyde dehydrogenase activity (ALDH+) on flow cytometry, these LSCs are resistant to currently existing treatments in AML such as cytarabine and anthracycline that, at the cost of great toxicity on normal cells, are highly active against the leukemic bulk, but spare the LSCs responsible for relapse. To try to combat the LSC population selectively, a well-characterized ALDH inhibitor by the trivial name of dimethyl ampal thiolester (DIMATE) was assessed on sorted CD34+CD38− subpopulations from AML patients and healthy patients. ALDH activity and cell viability were monitored by flow cytometry. From enzyme kinetic studies DIMATE is an active enzyme-dependent, competitive, irreversible inhibitor of ALDH1. On cells in culture, DIMATE is a powerful inhibitor of ALDHs 1 and 3, has a major cytotoxic activity on human AML cell lines. Moreover, DIMATE is highly active against leukemic populations enriched in LSCs, but, unlike conventional chemotherapy, DIMATE is not toxic for healthy hematopoietic stem cells which retained, after treatment, their self-renewing and multi-lineage differentiation capacity in immunodeficient mice, xenografted with human leukemic cells. DIMATE eradicates specifically human AML cells and spares healthy mouse hematologic cells.

International audience; Objective. – To study the efficacy and safety of micafungin for prophylaxis of invasive fungal infections in patients undergoing inductionchemotherapy for acute myeloid leukemia.Patients and methods. – A prospective observational single-center study of 41 patients from the hematology department between May 2012 andApril 2015. Micafungin was administered once daily from the first day of induction chemotherapy to the end of the neutropenic phase.Results. – Neither Candida nor Aspergillus infection was documented in our 41 patients from the first day of micafungin infusion to the end ofthe neutropenic phase. Patients were followed for three months after discontinuation of micafungin and none of them contracted an invasive fungalinfection. Only one patient presented with grade III–IV hepatic and ionic toxicities.Conclusion. – Micafungin is associated with a good safety profile and is an interesting option for preventing invasive fungal infections in thehigh-risk population of patients presenting with hematological disorders.

Introduction Community-acquired meningitis is a monomicrobial infection caused by either viruses or bacteria in the vast majority of patients. We report here one exceptional case of a patient with mixed bacterial meningitis due to Streptococcus pneumoniae and Streptococcus pyogenes. Case presentation We report the case of a 68-year-old immunocompromised Caucasian man suffering from otitis and then meningitis caused by Streptococcus pneumoniae and Streptococcus pyogenes. Bacteria were undistinguishable by direct microscopic examination of the cerebrospinal fluid. He responded well to treatment with cefotaxime and dexamethasone, with no sequelae observed at the 4-month follow-up. Conclusions This first reported case of mixed S. pneumoniae and S. pyogenes meningitis illustrates the life-threatening consequences of barotrauma in immunocompromised patients suffering from otorhinolaryngeal infections.

Le mycosis fungoide (MF) et le syndrome de Sezary (SS) sont des hemopathies T de pronostic sombre. Neanmoins, notre connaissance de ces pathologies s’est accrue de facon significative durant ces dernieres annees. Tout d’abord, la contrepartie cellulaire de ces pathologies a ete precisee : lymphocytes T centraux-memoires pour les cellules de Sezary, alors que les cellules de MF ont un phenotype de lymphocytes T effecteurs-memoires. Les etudes de genomique ont montre une hypermethylation correlee a l’agressivite de la maladie. Les etudes en microarrays ont determine des profils d’expression genique non entierement specifiques du MF ou du SS mais permettant de prevoir l’efficacite de drogues telles que l’interferon ou le vorinostat. De plus ces etudes en microarrays ont permis de mettre en evidence l’activation d’oncogenes ou de voies metaboliques orientant vers de nouvelles approches therapeutiques probablement combinees, puisque aucune drogue n’a montre a ce jour, en monotherapie, une grande efficacite dans les formes graves.

Lysozyme (ALys) amyloidosis (Online Mendelian Inheritance in Man 153450), first identified in 1993 by Pepys et al., is a very rare autosomal dominant hereditary non-neuropathic amyloidosis [1]. Lys...

Despite recent progress in the therapeutic approach of malignant haemopathies, their prognoses remain frequently poor. Immunotherapy offers an alternative of great interest in this context but defect or abnormal expression of human leukocyte antigens (HLA), frequently observed in cancer cells, limits its efficiency. Natural killer (NK) cells, which are able to kill target cells in a HLA-independent way, represent a novel tool in the treatment of haematological malignancies. Abnormal NK cytolytic function is observed in all the haematological malignancies studied, such as acute leukaemia, myelodysplastic syndromes or chronic myeloid/lymphoid leukaemia. Several mechanisms are involved in the alterations of NK cytotoxicity: decreased expression of activating receptors, increased expression of inhibitory receptors or defective expression of NK ligands on target cells. Further studies are needed to identify how each type of haematological malignancy escapes from the innate immune response. Attempts to increase the expression of activating receptors, to counteract inhibitory receptors expression, or to increase NK cell cytotoxic capacities could overcome tumour escape from innate immunity. These therapies are based on monoclonal antibodies or culture of NK cells in presence of cytokines or dendritic cells. Moreover, many novel drugs used in haematological malignancies [tyrosine kinase inhibitors, IMIDs(®), proteasome inhibitors, demethylating agents, histone deacetylase inhibitors (HDACis), histamine dihydrochloride] display interesting immunomodulatory properties that affect NK cells. These data suggest that combined modalities associating cytotoxic drugs with innate immunity modulators may represent a major breakthrough in tumour eradication.

Cytarabine (Ara-C) is the backbone for treating accute myeloid leukemia (AML). As most nucleoside analogs, Ara-C is metabolized in the liver by an exclusive enzymatic step driven by cytidine deaminase (CDA). CDA is a ubiquitous enzyme that proved to be highly polymorphic, with activities in patients ranging from poor metabolizer (PM) to ultra metabolizer (UM). To date, deregulated CDA has been evidenced as a culprit for life-threatening toxicities with gemcitabine. Little evidences have been collected thus far about the possible role erratic CDA could further play with Ara-C. Here, we investigated whether deregulations affecting CDA could be at the origin of unexpectedly severe, and sometimes lethal, toxicities with Ara-C in patients with AML. In this clinical observational study we determined CDA activity levels and searched for CDA genetic polymorphisms in 58 adult patients (25F, 33M, mean age 63 ±15 years) hospitalized for AML and scheduled for induction therapy. All patients were treated following current standard care by Ara-C-containing regimen (i.e., 7+3 protocol) and monitored for toxicity (CTCAEv4 grading) and response. Efficacy was evaluated one-month after starting the induction protocol. Mean CDA activity in the studied population was 3.14 ± 3 U/mg. No relationship was found between CDA phenotype and genotype (i.e., 79A>C polymorphism). A total of 20 patients (43%) displayed severe toxicities (i.e. grade-3 and above) upon administration, including 3 unrecoverable grade-5 toxicities (5%). Relationship between CDA activity and severe toxicity was investigated using ROC analysis. We observed that the incidence of CDA deficiency was much higher in AML patients (40%) than what we previously observed in patients with solid tumors. A cut-off value in CDA ≤ 2 U/mg was associated with increased risk of experiencing severe/lethal toxicities with 74% sensitivity and 65% specificity. Among the 20 patients with severe toxicities, 14 (72 %) were categorized as PM. Importantly, patients who experienced lethal toxicities were all profoundly PM patients. CR was achieved in 35 patients (60%), CRI achieved in 4 patients (7%) whereas 16 patients (27%) failed to respond (PD). No relationship was evidenced between CDA status and response, however regardless of the karyotype we observed that PM patients tended to have longer PFS (278 vs. 517 days) and OS (570 days vs. not reached) as compared with EM patients. Overall this proof-of-concept study strongly suggests that CDA status could be a relevant marker for predicting clinical outcome in patients treated with Ara-C, especially treatment-induced toxicities. A prospective study including full PK and pharmacogenetics support is currently ongoing in our institute to confirm these observations. Should the role CDA plays be confirmed, this marker could be used as a covariate to customize Ara-C dosing in AML patients. Citation Format: Raphaelle Fanciullino, Laure Farnault, Mélanie Donnette, Vadim Ivanov, Geoffroy Venton, Joseph Ciccolini, Yael Berda-Haddad, Catherine Roche, L'Houcine Ouafik, Bruno Lacarelle, Regis Costello. CDA predicts life-threatening toxicities in AML patients treated with cytarabine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3898.

The TNF member LIGHT also known as TL4 or TNFSF14) can play a major role in cancer control via its two receptors; it induces tumor cell death through lymphotoxin-beta receptor (LT-betaR) and ligation to the herpes virus entry mediator (HVEM) amplifies the immune response. By studying the effect of LIGHT in the transcriptional profile of a lymphoid malignancy, we found that HVEM, but not LT-betaR, stimulation induces a significant increase in the expression of chemokine genes such as IL-8, and an unexpected upregulation of apoptotic genes. This had functional consequences, since LIGHT, or HVEM mAb, thus far known to costimulate T- and B-cell activation, induced chronic lymphocytic leukemia cell death. Many of the mediators involved were identified here, with an apoptotic pathway as demonstrated by caspases activation, decrease in mitochondrial membrane potential, upregulation of the pro-apoptotic protein Bax, but also a role of TRAIL. Moreover, HVEM induced endogenous TNF-alpha production and TNF-alpha enhanced HVEM-mediated cell death. HVEM function was mainly dependent on LIGHT, since other ligands like HSV-glycoprotein D and B and T lymphocyte attenuator were essentially ineffective. In conclusion, we describe a novel, as yet unknown killing effect of LIGHT through HVEM on a lymphoid malignancy, and combined with induction of chemokine release this may represent an additional tool to boost cancer immunotherapy.

International audience; The family Marseilleviridae is a new clade of giant viruses whose original member, marseillevirus, was described in 2009. These viruses were isolated using Acanthamoeba spp primarily from the environment. Subsequently, a close relative of marseillevirus was isolated from the faeces of a healthy young man, and others were detected in blood samples of blood donors and recipients and in a child with lymph node adenitis. In this Grand Round we describe the detection of marseillevirus by PCR, fluorescence in-situ hybridisation, direct immunofluorescence, and immunohistochemistry in the lymph node of a 30-year-old woman diagnosed with Hodgkin's lymphoma, together with IgG antibodies to marseillevirus. A link with viruses and bacteria has been reported for many lymphomas. We review the literature describing these associations, the criteria used to consider a causal association, and the underlying mechanisms of lymphomagenesis. Our observations suggest that consideration should be given to marseillevirus infections as an additional viral cause or consequence of Hodgkin's lymphoma, and that this hypothesis should be tested further.

We report the case of a patient bearing a T315I-mutant chronic myeloid leukemia resistant to nilotinib, successfully treated with omacetaxine and then with dasatinib. After 9 months of nilotinib, the patient achieved a major molecular response but relapsed 3 months later due to the T315I mutation. Because third-generation tyrosine kinase inhibitor was not available and the patient refused bone marrow transplantation, he received two cycles of omacetaxine. This treatment had been stopped after two cycles because of clinical intolerance, but a major molecular response and total disappearance of the T315I clone was obtained. Treatment with dasatinib was then started and after 34-month follow-up the patient is still in major molecular response, thus suggesting that eradication of the T315I mutation could be achieved without third-generation tyrosine kinase inhibitors.

International audience; Azacitidine is a mainstay for treating hematological disorders. Azacitidine is metabolized by cytidine deaminase, coded by a highly polymorphic gene. Here, we present two elderly patients with opposite clinical outcomes after azacitidine treatment. First, an acute myeloid leukemia patient showed life-threatening toxicities, but outstanding complete remission, after a single round of azacitidine. Further investigations showed that this patient was cytidine deaminase 79A>C (rs2072671) homozygous with a marked deficient phenotype. Next, a chronic myelomonocytic leukemia patient displayed complete lack of response despite several cycles of azacitidine. This patient had a rapid-deaminator phenotype linked to the -31delC deletion (rs3215400). These polymorphisms lead to opposite clinical outcomes in patients with myelodysplastic syndromes treated with azacitidine, thus suggesting that determining cytidine deaminase status could help to forecast clinical outcome.

International audience; Azacytidine, an antimetabolite with an original epigenetic mechanism of action, increases survival in patients diagnosed with high-risk myelodysplasic syndromes or acute myeloid leukemia with less than 30% medullar blasts. Azacytidine is a pyrimidine derivative that undergoes metabolic detoxification driven by cytidine deaminase (CDA), a liver enzyme whose gene is prone to genetic polymorphism, leading to erratic activity among patients. Clinical reports have shown that patients with the poor metabolizer (PM) phenotype are likely to experience early severe or lethal toxicities when treated with nucleosidic analogs such as gemcitabine or cytarabine. No clinical data have been available thus far on the relationships between CDA PM status and toxicities in azacytidine-treated patients. Here, we measured CDA activity in a case of severe toxicities with fatal outcome in a patient undergoing standard azacytidine treatment. Results showed that the patient was PM (i.e. residual activity reduced by 63%), thus suggesting that an impaired detoxification step could have given rise to the lethal toxicities observed. This case report calls for further prospective studies investigating the exact role that CDA status plays in the clinical outcome of patients treated with azacytidine.

Background: Abnormal NK phenotype and cytotoxic functions have been described in acute myeloid leukemia, chronic lymphocytic leukemia, myeloma and myelodysplastic syndromes. Defective NK cytotoxicity is due to decreased expression of the Natural Cytotoxicity Receptors (NCRs), 2B4/CD244/p38, or NKG2D. This prompted us to test the expression of these molecules on circulating NK cells from patients with AIDS-related lymphomas (RL) in comparison with HIV + patients without lymphoma, healthy subjects and HIV-negative patients with lymphoma. Methods: Blood samples were analyzed by flow cytometry for NCRs, 2B4/CD244/p38 and NKG2D expression on NK cells defined as CD3-/CD56+ lymphocytes. We also analyzed by quantitative PCR specific RNA for NKp30/NCR3 and NKp46/NCR1. Results: We could not detect any defect in NKp46/NCR1 expression between all groups. NKp44/NCR2, NKp30/NCR3 and NKG2D had lower expression in AIDS-RL in comparison with HIV + patients without lymphoma when compared to patients with similar (>0.3 G/L) CD4+ lymphocyte levels. Expression of 2B4/CD244/p38 was lower in AIDS-RL than in HIV-negative lymphoma. Comparison of specific NKp30/NCR3 and NKp46/NCR1 RNA showed increased steady state levels, despite decreased surface expression for NKp30/NCR3, suggesting abnormal post-transcriptional regulatory mechanisms. Conclusions: We show a more pronounced defect in NK activating molecule when HIV infection is associated with lymphoma than when only one condition (HIV positivity or lymphoma) is present. Defective NK phenotype, in addition to CD4+ depletion and dysfunction, may participate to the increased incidence of lymphoma in HIV patients.

BACKGROUND Optimal treatment of human immunodeficiency virus (HIV)-associated non-Hodgkin lymphoma (NHL) has yet to be defined, because chemotherapy could exacerbate immunodeficiency, with subsequent adverse effects for patients. METHODS The authors investigated the feasibility of an intensive chemotherapy regimen for HIV-associated NHL. Thirty-eight patients were treated with a first course of cyclophosphamide (Cy), vincristine, and prednisone; followed by 3 courses of high-dose Cy (2000 mg/m2), doxorubicin (Doxo; 50 mg/m2), vincristine, and prednisone (modified high-dose CHOP); 1 course of high-dose methotrexate (MTX; 8000 mg/m2); and 1 course of high-dose cytarabine (8000 mg/m2). Radiotherapy was added to the treatment regimen for patients with bulky disease or residual tumor. Chemotherapy was administered in conjunction with granulocyte–colony-stimulating factor and antiretroviral therapy. RESULTS Patients received 91.5%, 93%, 66%, and 63% of the scheduled doses of Cy, Doxo, MTX, and cytarabine, respectively. The complete response rate was 60.5%, with a total response rate of 79%. The 40-month overall survival rate was 43%, the disease-free survival rate was 65%, and the recurrence-free survival rate was 39%. Both an International Prognostic Index score of 0 or 1 and Burkitt-type histology had positive effects on survival, whereas CD4-positive lymphocyte counts, viral burden, and previous highly active antiretroviral therapy did not. CD4-positive T lymphocyte levels decreased from 0.197 ± 0.156 ×109/L before treatment to 0.152 ± 0.1 ×109/L at 6 months after the end of treatment. A decrease in viral load, from 380,000 ± 785,000 copies/mL before treatment to 25,000 ± 43,000 copies/mL at 6 months after the end of treatment, also was observed. CONCLUSIONS The results of the current study indicate that intensive chemotherapy is effective and tolerable for patients with HIV-associated NHL. Cancer 2004;100:667–76. © 2004 American Cancer Society.

The immune system is a complex arrangement of cellular interactions that preserve the integrity of a organism by elimination of all elements judged dangerous. However, the development of tumours in immunocompetent patients suggests the existence of an imbalance that favours tumour cells against the immune response. What are the different possibilities for reversing this process to drive an efficient antitumour response? We discuss, focusing on the haematological features, classic immunity (ie, antigen-specific and HLA-restricted immunity). We address the central issues of tumour antigen presentation and recognition and their possible clinical use. Last, we discuss non-HLA-restricted immunity, which does not require the recognition of specific antigens and relies on particular cell populations such as natural killer cells.

LIGHT is a recently identified member of the TNF superfamily that is up-regulated on activated T cells and can cooperate with CD40L to condition DC for the priming of CTL. In this report, we show that an intracellular pool of LIGHT is found selectively in some CD45RA-CD27+CD4+ "central" memory T cells and to a greater extent in some CD45RA-CD27-CD4+ effector memory T cells. LIGHT, like CD40L, is rapidly up-regulated on memory CD4+ T cells upon activation. Unlike CD40L, LIGHT up-regulation on naive T cells is delayed. Stimulation of DC with each subset of memory T cells in the presence of superantigen revealed that CD40L and LIGHT are required for optimal secretion of IL-12. Moreover, effector memory T cells, which can interact with DC in peripheral tissues, contribute to CCR7 induction on DC. LIGHT and CD40L can also regulate IL-12 production by CCR7+ DC capable of migration to lymph nodes. These data suggest that both LIGHT and CD40L may be involved in the maintenance or reactivation of secondary Th1 responses.

Advances in the management of haematological malignancies have allowed to obtain improved remission rates. Nonetheless, relapses impair these results and justify the search for novel therapeutic strategies. Clinical data demonstrate that the immune system plays an important role in the control of haematological malignancies. An increased frequency of haematological malignancies is observed in immunodeficiency states. Reversal of the immunosuppression is sometimes sufficient to induce tumour regression (withdrawal of cyclosporine in post-transplant lymphoproliferations, highly active anti-retroviral treatment in human immunodeficiency virus related Kaposi's disease). Another line of evidence for the involvement of the immune system in the anti-tumour response comes from the observation of spontaneous anti-tumour responses that parallel the occurrence of paraneoplastic immune-mediated syndromes. Finally, the efficiency of allogeneic transplantation in the haematological field has been clearly demonstrated to depend on the immune-mediated graft vs. leukaemia effect. Nonetheless, tumours develop in immune competent patients because of various tumour escape mechanisms, such as loss of human leucocyte antigen class I antigens, absence of target recognition by deficient adhesion/co-stimulatory molecule expression, tumour cell counterattack against immune effectors, direct (contact-dependent) or indirect (cytokine-mediated) impairment of T-lymphocyte activation. Novel immunotherapy approaches are now orientated in a convergent direction, i.e. the reversal of immune escape mechanisms either via the correction of deficient phases of the immune response or by the amplification of physiological mechanisms.

We describe a patient with acute myeloid leukemia (AML) who developed polyclonal large granular lymphocyte (LGL) proliferation. The reciprocal evolution of AML and LGLs suggested that these LGLs had an anti-tumor activity. The patient's LGLs killed autologous leukemia cells in a different way to classical T lymphocyte-mediated cytotoxicity since it did not rely on the recognition of target antigens presented by major histocompatibility complex (MHC) class I molecules by the CD3/TcRalphabeta complex. This killing was also different from natural killer (NK)-mediated cytotoxicity, which depends on the absence of MHC class I molecule recognition by NK inhibitory receptors. The LGLs were polyclonal, had a CD3+/CD8+/CD56+ phenotype, and did not express the natural killer cell receptors (NKRs) for MHC class I molecules. The LGLs did not express the NK-specific activating natural cytotoxicity receptors but expressed the 2B4 non-MHC restricted triggering receptor, whose ligand CD48 was expressed by leukemic cells and normal bone marrow cells. The 2B4 receptor participated in the ability of LGLs to lyse patient's leukemia. This represents a novel function for 2B4 in man, since this molecule, at variance with the murine system, was considered not to have direct effects on CD8+ T cell-mediated cytotoxicity. This case report allowed us to describe a novel T lymphocyte-mediated anti-tumor mechanism which relied on (1) the abnormal expansion of the rare 2B4-positive CD3+/CD8+/CD56+ T lymphocyte subset, (2) an as yet undescribed cytotoxicity mechanism in man which depended on 2B4 molecule. The relevance of this observation in human cancer immunotherapy has to be further investigated.

Cutaneous T-cell lymphomas (CTCL) are a heterogeneous group of lymphomas primarily involving the skin. The most common types are mycosis fungoides (MF) and Sezary Syndrome (SS). We report a novel long-term fast-growing SS line termed BKP1 that was characterized by flow cytometry (FC), conventional and molecular cytogenetic [FISH/multi-FISH together with array comparative genomic hybridization (aCGH)]. FC immunophenotype of the BKP1 is CD2+CD5+CD3+CD4+CD8-CD7-CD25-CD26-CD30-CD158k+. The TCRγ characterization of BKP1 by PCR identified a clonal rearrangement. The conventional cytogenetic and Multi-FISH analysis showed complex chromosomal rearrangements. aCGH analysis highlighted the loss of genes involved in cell cycle control, in immune response (HLA, complement complex) and DNA damage repair mechanisms. The BKP1 is another lymphoma cell line thoroughly characterized that can be a valuable tool for both basic and applied research such as identification of deregulated genes and/or pathways and screening for new antilymphoma drugs.

Epigenetic drugs modify DNA methylation and are used in refractory anemia with excess of blasts (RAEB). These drugs may reactivate anti-oncogene expression and restore a normal phenotype instead of inducing antitumor toxicity, although they also have immunosuppressive effects on T-lymphocytes [1] In RAEB and acute myeloid leukemia, a defect in natural killer (NK) cell cytotoxicity has been shown, which relies on abnormal expression of activating receptors. Previous study has shown that 5-azacytidine impaired mRNA synthesis and induced apoptosis in NK cells [2]. In this study we investigated the effect of the demethylating drug 5-azacytidine (Vidaza®) on NK receptors with the hypothesis that demethylation of the promoters of activating NK receptor genes induces gene reactivation and thus may increase their expression., Highlights • We analyze the effects of the demethylating agent azacytidine on NK cells in RAEB. • The expression of NCRs and NKG2D activating molecules are not modified. • The expression of the co-stimulating molecule 2B4/CD244 is drastically decreased. • The expression of inhibitory NK cell molecules is not modified (data not shown). • These data argue for the association of demethylating agents with IMIDs in RAEB.

Hemolytic anemia is a rare disease classified as constitutional or acquired. This classification allows clinicians to adapt treatment to each type of etiology. The diagnosis of hemolysis itself relies on the observation of a regenerative anemia, jaundice, increased bilirubin and/or lacticodehydrogenase (LDH) and/or decreased haptoglobin level. Nonetheless, increased reticulocytes and bilirubin levels are delayed after the onset of hemolysis, and reticulocytes may decrease in the course of evolution by folate depletion that inhibits erythropoiesis. The distinction between intra-tissular hemolysis (increased LDH) and intravascular (decreased haptoglobin) is often difficult since the two components are often both involved. Complications of hemolytic anemia are related to anemia but also to the hemolysis itself, such as acute renal failure and thromboembolic events, and are thus to be carefully monitored more particularly in the setting of acute hemolysis. Management of hemolysis greatly depends on its etiology, from erythrocyte transfusion, immunosuppressive and immunomodulatory drugs, to plasma exchange or very specific treatment (such as Eculizumab in nocturnal paroxysmal hemoglobinuria). Diagnosis thus sometimes requires very specialized and sophisticated tests involving hematology, genetics and biochemistry laboratories that are mandatory to provide an adapted treatment.

It is now established that a subgroup of non-Hodgkin's lymphoma (NHL) patients probably benefit from high-dose therapy (HDT). We therefore retrospectively analyzed survival of 126 consecutive patients with large cell lymphoma (LCL) and high-intermediate (HI) or high-risk (H) age-adjusted international prognostic index (Aa-IPI). They received either standard chemotherapy (CT) (66 patients), or HDT (60 patients). Distribution of the Aa-IPI scores showed no statistical significant difference between the two treatment groups. Complete response (CR) rate was 51% for the whole series, with 41% and 62% for the standard CT group and HDT group, respectively. With a median follow-up of 63 months (range, 16 to 159), the 5-year overall survival (OS) and event-free survival (EFS) for all patients was 52% and 43%, respectively. There was a statistical significant difference in terms of survival towards the HDT group: OS at 76% vs 31%, EFS at 64% vs 24%. Patients who achieved CR with front-line therapy had a 5-year OS at 70%, while it was 34% for patients who were not in CR. These results are comparable to those reported in the literature, and strongly suggest that both initial CR achievement and HDT as front-line treatment are predictive factors for prolonged survival of patients with poor-risk LCL. Bone Marrow Transplantation (2000) 25, 35-40.

Minimally differentiated acute myeloid leukemia (AML-M0) is a rare FAB subtype (2-3% of AMLs) of poor prognosis. The aim of our study was to characterize AML-M0 expression and regulation of adhesion/costimulatory molecule involved in immune recognition, to test blast in vitro immunogenicity, and to determine the percentage of leukemia progenitor cells. Here, we demonstrate that alloimmune recognition of AML-M0 in primary mixed lymphocyte reaction, as evaluated by IL-2 secretion of responding T cells, is reduced in comparison with more differentiated subtypes (128 +/- 95 pg/ml vs304 +/- 159 pg/ml, P < 0.05). These data are in line with low blast cell expression of major histocompatibility complex (MHC) class II DR molecules, and of the CD28 ligand B7-2, which plays an important role in AML immune recognition. Adhesion/costimulatory molecules were up-regulated by leukemic cell stimulation via CD40, and, although less efficiently, by gamma-IFN; both stimuli improved blast cell immunogenicity. We also demonstrate that AML-M0 have a very high percentage (40% +/- 30) of CD34+/CD38- leukemic clonogenic precursors in comparison with more differentiated AMLs (2.5% +/- 2) or non-leukemic CD34+hematopoietic precursors (1.8% +/- 0.8). Since the presence of a leukemic cell population at an early differentiation stage has been identified as a poor prognostic factor, we conclude that the high frequency of CD34+/CD38- blasts in AML-M0 may converge with already identified poor prognosis factors such as chemotherapy resistance and cytogenetic abnormalities. The clinical implications of AML-M0 impaired in vitroimmunogenicity and a high percentage of CD34+/CD38- blasts will require comparative analysis of additional patients. The increased immunogenicity of blast cells after CD40 triggering provide interesting clues for AML-M0 immunotherapy, that have to be confirmed with an in vivo leukemia model in mice.

Pericentric inversion of chromosome 16, translocation (16;16) and del(16q), resulting in a chimerical fusion of CBFbeta and MYH11 genes, are typically seen in the M4Eo French-American-British (FAB) classification subset of acute myelogenous leukemia (AML). In this study, we analyzed 70 cases of acute non-lymphoblastic leukemia, mainly of the M4 or M5 type. We report the very unusual presence of the t(16;16) and CBFbeta/MYH11 fusion transcript in an M7 patient. Ten M4Eo and four non-M4Eo patients presented an inv(16), t(16;16) or CBFbeta/MYH11 fusion transcript. In most cases, the common 'A-type' CBFbeta/MYH11 fusion transcript was detected. In addition to the eight different breakpoints and the three alternative splicing variants already described, evidence of a new CBFbeta/MYH11 fusion transcript was found which involves a 785-bp deletion of MYH11. Moreover, two patients had an unusual transcript, to our knowledge only observed once. Only one patient had abnormal eosinophilic differentiation without chromosome 16 cytogenetic abnormalities or detectable CBFbeta/MYH11 fusion. Conversely, only one patient presented CBFbeta/MYH11 fusion without abnormal eosinophilic differentiation. Altogether, our data suggest a correlation between the CBFbeta/MYH11 fusion transcript and characteristic abnormal eosinophilic differentiation, whatever the FAB subtype or the percentage of abnormal eosinophils

International audience; Hematological malignancies (HM) treatment improved over the last years resulting in increased achievement of complete or partial remission, but unfortunately high relapse rates are still observed, due to remaining minimal residual disease.Therefore, sustainment of long-term remission is crucial, using either drug maintenance treatment or by boosting or prolonging an immune response. Immune system has a key role in tumor surveillance. Nonetheless, tumor-cells evade the specific T-lymphocyte mediated immune surveillance using many mechanisms but especially by the down-regulation of the expression of HLA class I antigens. In theory, these tumor-cells lacking normal expression of HLA class I molecules should be destroyed by natural killer (NK) cells, according to the missing-self hypothesis. NK cells, at the frontier of innate and adaptive immune system, have a central role in tumor-cells surveillance as demonstrated in the setting of allogenic stem cell trans-plantation. Nevertheless, tumors develop various mechanisms to escape from NK innate immune pressure. Abnormal NK cytolytic functions have been described in many HM. We present here various mechanisms involved in the escape of HM from NK-cell surveillance, i.e., NK-cells quantitative and qualitative abnormalities.

At present, allogeneic bone marrow transplantation (BMT) seems to be the only curative treatment for patients with chronic myeloid leukemia (CML). The mechanisms of this therapeutic approach probably include anti-leukemic immune response or "graft-versus-leukemia" (GVL) reaction against leukemic cell clones, since even aggressive chemotherapy is not sufficient per se to cure this type of disease. In many patients, allogeneic BMT results in the disappearance of the Ph chromosome; this negativity does not exclude the presence of residual leukemic cells since sensitivity of cytogenetic analysis is low. The chimeric BCR-ABL gene in CML is a tumor-specific marker that is well suited to allowing detection of low numbers of residual leukemic cells through the extremely sensitive detection method of polymerase chain reaction (PCR). Using this method, 1 leukemic cell in 10(5) or 10(6) normal cells can be detected. Many studies have evaluated the clinical significance and predictive value of BCR-ABL gene rearrangement detected by PCR assay after BMT, most often on heterogeneous populations. Results from such studies have been conflicting. We have conducted a review of the literature, focussing on long-term survivors (3 years from BMT) of CML to determine the value of PCR in such patients (n = 183). With the consideration that such a population is obviously heterogenous, long-term PCR negativity strongly correlated with achieving a cure since no patient relapsed in this population (n = 117). Among the PCR positive patients (n = 66), only 5 (8%) relapsed, suggesting a poor prognostic value for a PCR+ test36 months post-transplant. Besides the potential clinical value of these data, they contribute to the understanding of the biology of the disease and may suggest a crucial role for the long term GVL effect of marrow transplantation.

Acute promyelocytic leukemia (APL; M3 in the FAB classification) is specifically associated with the t(15;17)(q23;q12) and the consequent formation of a PML/RARA fusion gene. A few cases of APL with a t(11;17)(q23;q12) and a PLZF/RARA fusion gene have recently been reported. In addition, a new variant, t(5;17)(q32;q12), with a RARA rearrangement was described in a child with atypical APL. We report an unbalanced der(5)t(5;17) in an atypical APL case showing unusual dysgranulopoiesis and some M2 features. The breakpoints were difficult to localize precisely on chromosome 5, because the translocation may have occurred on a previous del(5q). The karyotype also showed del(8q) and multiple double-minutes (dmin). Molecular studies evidenced RARA rearrangement but showed neither PML rearrangement nor PML/RARA fusion. Fluorescence in situ hybridization revealed that the dmin were of chromosome 8 origin and that they accounted for the MYC amplification observed in Southern blots. The patient did very poorly despite chemotherapy and all-trans retinoic acid (ATRA) treatment. Thus, the t(5;17) could represent a second type of variant translocation in APL that, like the disease associated with t(11;17), does not seem to respond to ATRA therapy. Whereas RARA rearrangement appears sufficient for an APL-like phenotype, it seems that the presence of a classical PML/RARA is required for typical APL with response to ATRA.

Summary. The Philadelphia chromosome (Ph) is the cytogenetic hallmark of chronic myeloid leukaemia (CML) and is used to confirm the diagnosis of CML based on clinical and morphological criteria. We investigated 14 patients with features of CML but without detectable Ph chromosome. In seven patients, referred to as BCR+, M-bcr/abl rearrangement was detected by polymerase chain reaction (PCR). The seven remaining patients did not have M-bcr/abl rearrangement and are described as BCR. BCR patients were younger, had lower white blood cell counts (WBC) and lower basophilia. Four BCR- and four BCR+ patients underwent blastic transformation (BT), Response to therapy was fairly similar in both populations. According to French-American-British (FAB) Cooperative Leukaemia Group guidelines, all BCR˜ patients were classified as having classic form CML or‘chronic granulocytic leukaemia’(CGL) when based only on morphological data. This study further confirms the existence of true CML cases without Ph chromosome or M-bcr/abl rearrangement and shows that this entity differs only slightly from classic form Ph+ CML. The Ph-BCR- subgroup raises two problems. First, the differential diagnosis with atypical CML or CMML, based on morphological data, and secondly, the therapeutic follow-up in the absence of a specific marker. In contrast, the residual disease of Ph˜BCR˜ patients can be monitored by PCR. More advanced molecular and biochemical techniques will be required to understand which molecular mechanisms underlie Ph-BCR- CML, resulting in phenotypes sometimes indistinguishable from Ph+ CML.

Over 70 MLL partner genes have been reported so far. MLL gene (or 11q23) translocation is occurring in 7-10% of B acute lymphoblastic leukemias and AF4 being the most frequent partner gene. The prognostic is usually bad, specially for AF4 partner. A rare partner gene, mastermind like 2 (MAML2) gene has been reported in 4 cases of myeloid neoplasms after chemotherapy so far: 2 AML and 2 MDS. Here we report a case with MLL - MAML2 discovered by NGS analysis in front of an inv11 (q21q23) present in a 47 years old female previously treated for a sarcoma in 2014. It is, to our knowledge, the first case of B acute lymphoblastic leukemia (CD79a, CD22, CD19, CD45, CD10-) with this fusion gene. At the molecular level, the rearrangement consists in the fusion of exons 7 and 2 of the MLL and MAML2 genes respectively. We will discuss the biological, clinical, physiological and therapeutic consequences of this rare event. Its prognostic impact is unknown as the reported cases are too rare. Citation Format: Fabrice Usseglio, Nathalie Beaufils, Régis Costello, Jean Gabert. First case of B LAL with MLL - MAML2 rearrangement. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3985.

Resume Dans la litterature, les rares cas recenses d’infections osteoarticulaires a Staphylococcus lugdunensis attestent de la gravite du tableau clinique, de la difficulte du diagnostic et du traitement. Nous rapportons l’observation d’un patient de 67 ans porteur d’un myelome a IgAλ stade III sous chimiotherapie developpant une spondylodiscite lombaire a Staphylococcus lugdunensis. L’evolution clinique de ce sujet immunodeprime a ete satisfaisante grâce a une bi-antibiotherapie ofloxacine–pristinamycine maintenue un an, en depit d’une reponse tardive au traitement antibiotique puisque l’amelioration clinique est survenue apres cinq mois de traitement. Le recul clinique est actuellement de trois ans.

Recent advances in chronic lymphocytic leukaemia (CLL) treatment, more particularly through upfront use of anti-CD20 monoclonal antibodies, have prolonged patient progression-free survival. Nonetheless, apart from allogeneic stem cell transplantation, no curative treatment is available. One possible explanation for the lack of cure in CLL could be a defective immune anti-tumour response. As the result of abnormal HLA class I molecule expression, CLL cells escape from specific T-lymphocyte immunity but should be the target for the innate natural killer (NK) cell-mediated immune response. Defective NK cytotoxicity as the result of decreased expression of the natural cytotoxicity receptors (NCRs) NKp30/NCR3, NKp44/NCR2 and NKp46/NCR1 has been described in haematological malignancies such as acute myeloid leukaemia. This prompted us to focus our attention on NCR expression on NK cells from patients with CLL. Although we failed to detect any difference between CLL patients and healthy age-matched controls, a precise analysis of clinical data showed a correlation between decreased NCR expression and poor prognosis factors such as low haemoglobin level, high (> 30 × 109 per litre) lymphocyte count or elevated C-reactive protein. Together, these observations support the rationale for restoration of normal NK cell functions in patients with CLL, putatively through the use of immune therapy protocols that already have demonstrated some benefit in acute myeloid leukaemia such as interleukin-2 plus histamine dihydrochloride.

Les anemies hemolytiques par anomalie de la membrane erythrocytaire sont diagnostiquees par l’observation du frottis sanguin a la recherche d’anomalies morphologiques. Elles se traduisent le plus souvent par une hemolyse chronique. Parmi les anemies hemolytiques par deficit enzymatique, le deficit en glucose-6-phosphate-deshydrogenase (G6PD) est le plus frequent. L’hemoglobinurie paroxystique nocturne est en relation a l’expansion d’un clone hematopoietique comportant une mutation d’un gene requis pour la synthese d’un radical lipidique rattachant de multiples molecules a la membrane. Certaines de ces molecules protegent le globule rouge de sa destruction par les fractions du complement. Dans les anemies hemolytiques extra-corpusculaires non immunologiques, l’agression du globule rouge par des agents externes aboutit a sa destruction. Un signe commun a ces pathologies est la presence dans le sang de globules rouges dechiquetes, appeles schizocytes. Les anemies hemolytiques auto-immunes sont dues a la fixation d’autoanticorps a la surface des globules rouges. L’element central du diagnostic est le test de Coombs direct qui met en evidence la presence de l’anticorps a la surface du globule rouge. Le test de Coombs indirect detecte ce meme anticorps, non entierement fixe sur les globules rouges, au niveau du serum.

Peripheral T-cell lymphomas constitute a heterogeneous group with regard to diagnosis, treatment and prognosis. Efforts have been made to combine novel techniques with cytology and immunochemistry in order to more precisely define these entities. Molecular profiling has contributed to novel insights in the biology of T-cell lymphoma. Regarding anaplastic large cell lymphoma, low expression T-cell receptor signalling and high STAT3 target signatures have been associated with the ALK-positive subgroup. Gene expression profiling differentiates angioblastic T-cell lymphoma from other T-cell malignancies, suggests that the normal counterpart of lymphoma cells are follicular helper T cells, and supports the involvement of vascular endothelial growth factor deregulation in its physiopathology. In peripheral T-cell lymphoma unspecified, gene profiling suggests the normal counterpart of tumour cells are activated CD4(+) or CD8(+) T-lymphocytes, delineates prognostic groups depending on the proliferative signature, and suggests therapeutic options aimed at regulating nuclear factor-kappaB and platelet-derived growth factor receptor-alpha phosphorylation. Gene expression profiling of primary cutaneous T cell lymphomas highlighted the importance of abnormal methylation patterns, suggested a pivotal role for JUNB/AP-1, and defined a predictive model for response to interferon-alpha. In conclusion, gene expression profiling is beginning to change the pathological classification, the prognosis profiles and the therapeutic approach in T-cell lymphomas.

Mixed warm and cold autoimmune anaemia is a rare haemolytic anaemia that is commonly associated with lymphoproliferative disorders and autoimmune diseases. Although steroid therapy is the first-line treatment, rituximab represents a good alternative. The present study reports on a successful treatment with rituximab in a young woman suffering from a mixed warm and cold autoimmune haemolytic anaemia associated with a mixed connective tissue disease.

Reversal of drug resistance is of pivotal importance in order to improve the results of chemotherapy. Monitoring of such reversal is necessary in order to analyze the results of clinical trials. Nonetheless, the leukemia cell population to eradicate is the leukemia initiating cells characterized by a CD34+CD38- phenotype. The evaluation of novel drug resistance modulators should be performed both in the whole leukemic cell population and in the leukemia initiating cell compartment, that is responsible for "mature" leukemia cells replenishment.

Restoration of immune functions is of importance in tumour eradication, more particularly regarding the residual disease. The challenge is probably to restore both innate and specific immune response, both required to overcome the various tumour escape mechanisms developed by leukemia cells. In the work of Lion et al., a simple method (electroporation of leukemic cell) may both restore NK and DC functions, leading to improved direct cytolysis by NK in addition to the development of a T-lymphocyte specific immune response.

7075 Background: Cytarabine is mainstays for treating hematological malignancies. As most nucleosidic analogs, cytarabine is metabolized in the liver by an exclusive enzymatic pathway driven by cyt...

Introduction Le myelome multiple (MM) et l’amylose AL (AAL) se compliquent frequemment d’une insuffisance renale aigue ou chronique qui greve leur pronostic et peut necessiter un traitement de suppleance par dialyse chronique. Les nouvelles chimiotherapies telles que le bortezomib ont ameliore le pronostic global des patients atteints de MM ou d’AAL, mais leur benefice n’est pas demontre chez les patients en dialyse chronique. L’objectif de cette etude etait d’analyser la survie en dialyse et les facteurs de risque de mortalite des patients atteints de MM ou d’AAL incidents en dialyse chronique entre janvier 2002 et decembre 2011 en France a partir des donnees du registre national REIN. Patients et methodes Tous les patients incidents en dialyse chronique entre 2002 et 2011 du fait d’un rein myelomateux, d’une amylose AL ou d’une maladie de Randall, enregistres dans REIN, ont ete inclus. La survie, les facteurs de risque de deces, les causes de deces et la recuperation renale ont ete analyses. La survie et le sevrage de la dialyse ont ete compares selon deux periodes : de 2002 a 2005 (avant l’utilisation du bortezomib chez les patients avec atteinte renale) et de 2006 a 2011. Les patients hematologiques ont ete compares a une cohorte de patients dialyses temoins. Resultats Parmi les 63 349 patients incidents en dialyse entre 2002 et 2011, 1462 (2,3 %) patients etaient en dialyse du fait d’une gammapathie monoclonale : rein myelomateux pour 861 (59 %), amylose AL pour 267 (18 %) et maladie de Randall pour 334 (23 %) patients. Le suivi median etait de 13,1 mois (IQR 4–33). L’âge median etait de 72,3 ans (63,9–78,9) avec 55,7 % d’hommes. Au cours du suivi, 982 (77,2 %) patients sont decedes. La mediane de survie en dialyse chronique etait de 18,3 mois (IC95 % 16,3–19,9) alors qu’elle etait de 51,6 mois (IC95 % 49,6–54,1) dans la cohorte controle de patients dialyses chroniques. Les causes de deces etaient principalement neoplasiques (34 %), cardio-vasculaires (18 %) ou infectieuses (13 %). Les facteurs de risque de deces ajustes en analyse multivariee etaient l’âge (HR 1,026 – p Conclusion Ces donnees confirment le pronostic sombre des patients mis en dialyse suite a un MM, une AAL ou une maladie de Randall, avec neanmoins une amelioration de la survie au cours du temps entre 2002 et 2011. L’incidence du sevrage de la dialyse chez des patients pourtant consideres comme chroniques a augmente de facon significative entre 2002–2005 et 2006–2011, apres l’utilisation large du bortezomib chez les patients avec atteinte renale.

Cytotoxic immune cells play a role against infectious or tumour invasion. There are two types of cytotoxic cells : those involved in innate or natural immunity (natural killer cells, Tgammadelta lymphocytes, NKT cells) and those involved in the adaptive or acquired immunity (cytotoxic T lymphocytes). Recent advances in immunology have allowed the characterisation of unconventional cytotoxic populations, to better individualise the real cytotoxic cells within the traditional CD8+ T-cell population, and finally to get more insights into the activation of the cytotoxicity properties, in particular with regard to NK cells. The data recently acquired concerning the effector cytotoxic cells contribute to a better understanding of the interactions between the immune system and tumour cells. This may provide rational basis for combined immunotherapy protocols.

Human natural killer (NK) cells are potent effectors involved in destruction of virus infected cells and tumours. Their cytolytic function is regulated by surface receptors that either inhibit or increase the NK-mediated cytotoxicity. Under physiological conditions, NK cells recognize major histocompatibility complex (MHC)-class I molecules through surface receptors delivering signals that inhibit NK cells function. Nonetheless, the "missing self hypothesis", i.e. the release of an inhibitory signal by the interaction between HLA I-specific inhibitory receptors and their ligands, is not sufficient to entirely explain the regulation of NK cytotoxicity. Activating and co-receptors also play a central role in NK cell activation. In the haematology field, several lines of evidence suggest that NKs participate to the anti-leukaemia immune response: (1) leukaemic cells have down-regulated HLA-class I molecule expression and putative allele loss, (2) several reports have indicated an inverse relationship between NK cell number or activity and prognosis in acute leukaemia, (3) NK-cell activity dependent immunodeficiency syndromes are associated with an increased frequency of lymphoid haematological malignancies, (4) recent data support a role for NK cells in the graft-versus-leukaemia effect observed in allogeneic bone marrow transplantation. All these data raise several questions. How NK cells kill leukaemic targets, and how can leukaemia escape from innate immunity surveillance? What are the therapeutic possibilities to manipulate NK receptor-ligand interaction in order to increase leukaemia cell destruction? The responses to these questions will contribute to immunotherapy advancements in leukaemia and more generally in cancer.

Stimulation by CD40 ligand (L) improves B-cell malignancy immunogenicity, and also induces proliferative signals. To avoid these tumorigenic effects, we studied an alternate way of tumor-cell stimulation by homologous to lymphotoxin, inducible expression, competing for GpD of herpesvirus, which binds to the herpesvirus entry mediator (HVEM), and is expressed on T-lymphocytes (LIGHT), the ligand for HVEM, a new member of the tumor necrosis factor (TNF)/TNF-receptor (-R) family. HVEM is constitutively expressed on the surface of tumor B cells. We focused our attention on mantle cell lymphoma, a subtype of B-cell malignancy of poor prognosis. Triggering by LIGHT, in contrast to CD40L stimulation, did not increase lymphoma proliferation nor decrease chemotherapy entrance. We observed an upregulation of the TNFR apoptosis-inducing ligand Fas, and in contrast to CD40L-induced protection, an enhancement of lymphoma sensitivity to Fas-induced apoptosis. LIGHT triggering increased lymphoma cell recognition in a mixed lymphocyte response. In conclusion, LIGHT-mediated triggering renders B-cell lymphomas more immunogeneic and sensitive to apoptosis, without inducing proliferation. Since LIGHT triggering also enhances the functions of T-lymphocytes and dendritic cells, it could be a unique way to restore an efficient cancer control by its pleiotropic effects on immune effectors and tumor cells.