Nicotinaldehyde, a Novel Precursor of NAD Biosynthesis, Abrogates the Anti-Cancer Activity of an NAD-Lowering Agent in Leukemia.

Targeting NAD depletion in cancer cells has emerged as an attractive therapeutic strategy for cancer treatment, based on the higher reliance of malignant vs. healthy cells on NAD to sustain their aberrant proliferation and altered metabolism. NAD depletion is exquisitely observed when NAMPT, a key enzyme for the biosynthesis of NAD, is inhibited. Growing evidence suggests that alternative NAD sources present in a tumor environment can bypass NAMPT and render its inhibition ineffective. Here, we report the identification of nicotinaldehyde as a novel precursor that can be used for NAD biosynthesis by human leukemia cells. Nicotinaldehyde supplementation replenishes the intracellular NAD level in leukemia cells treated with NAMPT inhibitor APO866 and prevents APO866-induced oxidative stress, mitochondrial dysfunction and ATP depletion. We show here that NAD biosynthesis from nicotinaldehyde depends on NAPRT and occurs via the Preiss-Handler pathway. The availability of nicotinaldehyde in a tumor environment fully blunts the antitumor activity of APO866 in vitro and in vivo. This is the first study to report the role of nicotinaldehyde in the NAD-targeted anti-cancer treatment, highlighting the importance of the tumor metabolic environment in modulating the efficacy of NAD-lowering cancer therapy

A novel anti-CD19 monoclonal antibody (GBR 401) with high killing activity against B cell malignancies.

BACKGROUND: CD19 is a B cell lineage specific surface receptor whose broad expression, from pro-B cells to early plasma cells, makes it an attractive target for the immunotherapy of B cell malignancies. In this study we present the generation of a novel humanized anti-CD19 monoclonal antibody (mAb), GBR 401, and investigate its therapeutic potential on human B cell malignancies. METHODS: GBR 401 was partially defucosylated in order to enhance its cytotoxic function. We analyzed the in vitro depleting effects of GBR 401 against B cell lines and primary malignant B cells from patients in the presence or in absence of purified NK cells isolated from healthy donors. In vivo, the antibody dependent cellular cytotoxicity (ADCC) efficacy of GBR 401 was assessed in a B cell depletion model consisting of SCID mice injected with healthy human donor PBMC, and a malignant B cell depletion model where SCID mice are xenografted with both primary human B-CLL tumors and heterologous human NK cells. Furthermore, the anti-tumor activity of GBR 401 was also evaluated in a xenochimeric mouse model of human Burkitt lymphoma using mice xenografted intravenously with Raji cells. Pharmacological inhibition tests were used to characterize the mechanism of the cell death induced by GBR 401. RESULTS: GBR 401 exerts a potent in vitro and in vivo cytotoxic activity against primary samples from patients representing various B-cell malignancies. GBR 401 elicits a markedly higher level of ADCC on primary malignant B cells when compared to fucosylated similar mAb and to Rituximab, the current anti-CD20 mAb standard immunotherapeutic treatment for B cell malignancies, showing killing at 500 times lower concentrations. Of interest, GBR 401 also exhibits a potent direct killing effect in different malignant B cell lines that involves homotypic aggregation mediated by actin relocalization. CONCLUSION: These results contribute to consolidate clinical interest in developing GBR 401 for treatment of hematopoietic B cell malignancies, particularly for patients refractory to anti-CD20 mAb therapies

Transfer of human systemic lupus erythematosus in severe combined immunodeficient (SCID) mice

To study the role of peripheral blood leukocytes (PBL) in the pathogenesis of human systemic lupus erythematosus (SLE), we transferred PBL from 5 SLE patients into 15 severe combined immunodeficiency (SCID) mice. Such reconstituted mice showed long-term presence of auto-antibodies characteristic of the donor in their sera, as well as human immunoglobulin deposition, and in some cases mouse C3, in the renal glomeruli. SCID mice repopulated with PBLs from normal donors do not develop serologic abnormalities or immunodeposits. It is concluded that human SLE serology and some associated renal changes can be reproduced solely by PBL transferred from afflicted patients, and that SCID-human-SLE mice may serve as an in vivo laboratory model for the study of human SLE

A critical role of autophagy in antileukemia/lymphoma effects of APO866, an inhibitor of NAD biosynthesis.

APO866, an inhibitor of NAD biosynthesis, exhibits potent antitumor properties in various malignancies. Recently, it has been shown that APO866 induces apoptosis and autophagy in human hematological cancer cells, but the role of autophagy in APO866-induced cell death remains unclear. Here, we report studies on the molecular mechanisms underlying APO866-induced cell death with emphasis on autophagy. Treatment of leukemia and lymphoma cells with APO866 induced both autophagy, as evidenced by an increase in autophagosome formation and in SQSTM1/p62 degradation, but also increased caspase activation as revealed by CASP3/caspase 3 cleavage. As an underlying mechanism, APO866-mediated autophagy was found to deplete CAT/catalase, a reactive oxygen species (ROS) scavenger, thus promoting ROS production and cell death. Inhibition of autophagy by ATG5 or ATG7 silencing prevented CAT degradation, ROS production, caspase activation, and APO866-induced cell death. Finally, supplementation with exogenous CAT also abolished APO866 cytotoxic activity. Altogether, our results indicated that autophagy is essential for APO866 cytotoxic activity on cells from hematological malignancies and also indicate an autophagy-dependent CAT degradation, a novel mechanism for APO866-mediated cell killing. Autophagy-modulating approaches could be a new way to enhance the antitumor activity of APO866 and related agents

Radiological profile of anemia on unenhanced MDCT of the thorax.

Our aim was to investigate the diagnostic value of unenhanced MDCT in anemic patients. Fifty consecutive patients with proven anemia and 50 nonanemic matched group for age, sex and body mass index were evaluated. In either group, hemoglobin levels were assessed no more than 24 h from an unenhanced CT of the thorax. For each patient, the presence of a hyperattenuating aortic wall (aortic ring sign) and/or dense interventricular septum (subjective parameters) were identified by two radiologists who were blinded to the laboratory findings. Furthermore, the aortic CT attenuation values (objective parameter) were also obtained and correlated with the hemoglobin levels. The sensitivity and specificity in detecting anemia were calculated for each variable, and ROC analysis was generated for subjective and objective parameters. Subjective image analysis revealed that the aortic ring sign was more sensitive than the interventricular septum sign for anemia detection (84% vs. 72%), whereas this latter sign was more specific (100% vs. 92%). A good correlation (r = 0.60) was observed between the aortic CT attenuation values and the hemoglobin levels in the whole study population. Using a threshold of < or = 35 HU for anemia diagnosis, the sensitivity and specificity of aortic CT attenuation value were 84% and 94%, respectively, with the largest area under the curve (0.89) among all diagnostic criteria. However, the best trade-off between sensitivity (80%) and specificity (100%) was obtained from combining both subjective and objective analysis. Interpreting anemia upon unnenhanced MDCT of the thorax is quite feasible. A diagnostic approach that considers both subjective and objective analysis offers the best trade-off between sensitivity and specificity

Current status and updated recommendations for diagnosis and treatment of plasma cell myeloma in Switzerland

The availability of drugs such as thalidomide, bortezomib and lenalidomide changed the landscape in myeloma treatment and has extended the median survival up to 10 years with a substantial improvement in quality of life. This development prompted a Swiss expert panel to re-evaluate the current status and formulate updated clinical recommendations for the diagnosis and treatment of plasma cell myeloma. These recommendations should help clinicians in their decision making to achieve the best outcome based on currently available data

Haematopoietic cell transplantation in Switzerland, changes and results over 20 years: a report from the Swiss Blood Stem Cell Transplantation Working Group for Blood and Marrow Transplantation registry 1997-2016.

In 1997, the Swiss Blood Stem Cell Transplantation Group (SBST) initiated a mandatory national registry for all haematopoietic stem cell transplants (HCTs) in Switzerland. As of 2016, after 20 years, information was available for 7899 patients who had received an HCT (2781 allogeneic [35%] and 5118 autologous [65%]). As some patients had more than one transplant the total number of transplants was 3067 allogeneic and 6448 autologous. We compared patient characteristics and outcome of the first decade (1997-2006) and second decade (2007-2016) of the registry. There were numerous changes over time. For allogeneic HCT, transplant rates, and therefore use of HCT technology, increased from 14 to 21.8 HCTs per 1 million inhabitants per year from the first to the second decade. Likewise autologous HCTs increased from 24.8 to 37.2 annually corrected for population growth. Allogeneic transplant recipients were older (38.4 vs 48.3 years) and more frequently had unrelated donors in the second decade. Similarly, age increased for recipients of autologous HCT (50.8 vs 56.4 years). Analysis of outcome showed that the probabilities of overall and progression-free survival were stable over time, in spite of the treatment of older and higher risk patients. In multivariate analysis, nonrelapse mortality decreased in recipients of allogeneic HCT (relative risk 0.68, 95% confidence interval 0.52-0.87) over the two decades. Improvement in adjusted nonrelapse mortality compensated for the fact that higher risk patients were treated in more recent years, resulting in similar overall survival. Five-year survival probabilities were 56% (53-59%) in the first and 54% (51-57%) in the second decade for allogeneic HCT, and 59% (57-61%) in the first and 61% (59-63%) in the second decade for autologous HCT. Detailed analyses of changes over time are presented. This study included all HCTs performed in Switzerland during the period of observation and the data are useful for quality assurance programmes, healthcare cost estimation and healthcare planning. Between 50 and 60% of patients were long-term survivors after both types of HCT, indicating growing populations of surviving patients requiring long-term care and observation

A novel potent Fas agonist for selective depletion of tumor cells in hematopoietic transplants

There remains a clear need for effective tumor cell purging in autologous stem cell transplantation (ASCT) where residual malignant cells within the autograft contribute to disease relapse. Here we propose the use of a novel Fas agonist with potent pro-apoptotic activity, termed MegaFasL, as an effective ex-vivo purging agent. MegaFasL selectively kills hematological cancer cells from lymphomas and leukemias and prevents tumor development at concentrations that do not reduce the functional capacity of human hematopoietic stem/progenitor cells both in in vitro and in in vivo transplantation models. These findings highlight the potential use of MegaFasL as an ex-vivo purging agent in ASCT