Oral Supplementation with Omega3 Fatty Acids Inhibits NFkB Activation In Chronic Lymphocytic Leukemia (CLL) Cells.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4607-4607
Author(s):  
Oscar F. F Ballester ◽  
Johannes Fahrmann ◽  
Theodore Witte ◽  
Gabriela Ballester ◽  
W. Elaine Hardman

Abstract Abstract 4607 Introduction: Nuclear factor kappa B (NFkB) is a critical transcription factor involved in the growth and survival of CLL cells. NFkB is recognized as an important target for the development of novel therapies for the treatment of various malignancies. In vitro and in experimental animal models, OMEGA-3 fatty acid (O3FA) supplementation has been shown to inhibit NFkB activity. Patients and Methods: Patients with early stage CLL (Rai stages 0-II) who required no therapy, where accrued to this phase I-II trial. O3FA supplements were given for a total of 12 months at doses ranging from 2250 mg (EPA plus DHA), escalated to 4500 mg and 6750 mg per day as tolerated. NFkB activity was measured in peripheral blood samples after separation of mononuclear cell by gradient centrifugation and expressed as luminescence units/μ g of protein. Baseline and multiple serial samples were obtained during the study period. In-vitro cytotoxicity assays to doxorubicin were conducted using standard LD50 methods. Compliance was monitored by analysis of red cell and lymphocyte membrane lipid composition by gas chromatography. Results: Fifteen patients have been accrued to the trial, 8 of them have currently completed the planned 12 months of the study period. No significant clinical changes in disease activity were noted. O3FA was well tolerated. Supplementation resulted in a dose-dependent increase of O3FA composition of red cell and lymphocyte membranes in a dose dependent manner. At baseline, CLL patients had NFkB above the range observed in normal controls (2.05 × 104 to 2.32 × 105 NFkB lum units/μ g). The median value in CLL patients at baseline was 11.60 × 106 NFkB lum units/μ g (range 0.9 × 105 to 23.12 × 106). Among 5 patients with the highest baseline levels of NFkB, a decrease in NFkB activity ranging from 0.02 to 0.19 of the baseline value, was noted at the 2 higher doses of O3FA supplementation. Similar results were seen in patients with relatively lower levels of baseline NFkB activity (0.9 × 105 to 2.96 × 106 lum units/μ g). In vitro, significant doxorubicin cytotoxicity (>50%) was noted in samples obtained during supplementation, at μ gM concentrations which produced no detectable cell kill in baseline samples. Conclusions: O3FA supplementation resulted in significant inhibition of NFkB activity in leukemic cells from patients with CLL. In-vitro, after O3FA supplementation CLL cells became more sensitive to doxorubicin. Preliminary analysis of whole genome micro arrays revealed significant down-regulation of multiple genes associated with O3FA supplementation. Disclosures: No relevant conflicts of interest to declare.

Blood ◽  
1997 ◽  
Vol 89 (9) ◽  
pp. 3378-3384 ◽  
Author(s):  
Beatriz Bellosillo ◽  
Mireia Dalmau ◽  
Dolors Colomer ◽  
Joan Gil

Abstract B-chronic lymphocytic leukemia (B-CLL) is characterized by the accumulation of long-lived B lymphocytes that express high levels of Bcl-2. We examined the involvement of CED-3/ICE-like proteases in the apoptosis of B-CLL cells. One of the substrates of these proteases is poly(ADP [adenosine 5′-diphosphate]-ribose) polymerase (PARP). The effect of different factors that induce the apoptosis of B-CLL cells on the proteolytic cleavage of PARP has been studied. Treatment of B-CLL cells with different concentrations of dexamethasone (1 to 1,000 μmol/L) induced in a dose-dependent manner the cleavage of PARP. Dexamethasone induced PARP cleavage after 12 hours of incubation, which was almost complete at 48 hours. PARP cleavage during apoptosis of B-CLL cells was studied in cells from eight patients and a correlation was found between cell viability and the degree of PARP cleavage. Incubation in vitro of B-CLL cells with fludarabine for 48 hours induced PARP cleavage in all the cases studied. Protein kinase C (PKC) activation with 100 nmol/L TPA (12-O-tetradecanoylphorbol 13-acetate) or incubation with interleukin-4 (10 ng/mL) prevented either dexamethasone- or fludarabine-induced proteolysis of PARP. Incubation of B-CLL cells with the CED-3/ICE–like protease inhibitor Z-VAD.fmk inhibited spontaneous and dexamethasone-induced PARP cleavage and DNA fragmentation in a dose-dependent manner. Furthermore, Z-VAD.fmk prevented the cytotoxic effect of dexamethasone. These results indicate that CED-3/ICE–like proteases play an important role in the apoptosis of B-CLL cells.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 587-587
Author(s):  
Yuji Miura ◽  
Elinor Lee ◽  
Federica Gibellini ◽  
Therese White ◽  
Gerald Marti ◽  
...  

Abstract Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of mature B lymphocytes in the peripheral blood (PB), lymph nodes (LN) and bone marrow (BM). Increasing evidence suggests that CLL cells depend on survival and proliferation signals provided by stroma cells in LN and BM. The chemokine receptor CXCR4 (CD184) and its ligand stromal cell-derived factor-1 (SDF-1) play an important role in trafficking of lymphocytes and may guide CLL cells to stroma cell niches. ZAP70 expression has prognostic value in CLL but the functional consequences of ZAP70 expression remain incompletely defined. Given that ZAP70 has been implicated in CXCR4 signaling its expression could enhance migration to SDF-1 and thereby promote interactions with stroma cells. As measured by flow cytometry, CXCR4 expression on leukemic cells obtained from different anatomic sites differed; cells from the PB (n=24, median 71% above isotype control) expressed CXCR4 more strongly than cells from BM (n=21, median 39%) and from LN (n=9, median 24%). Expression of CD69, an activation marker, followed a reverse pattern with cells from LN and BM typically showing higher expression than cells from PB, albeit with not detectable difference in expression in several patients. In vitro CLL cells from PB migrated in a dose dependent manner to SDF-1, and cells that had migrated down-modulated CXCR4 expression (89% before migration - 54% after migration). After exposure to SDF-1 CXCR4 expression decreased rapidly and remained virtually absent for at least 24 hours. Several mechanisms apparently decrease CXCR4 expression after contact with SDF-1, including internalization (given rapid re-expression of CXCR4 when SDF-1 is washed off after short exposure), protein degradation or inhibition of translation (evidenced by a decrease in total CXCR4 protein on Western blots), and mRNA degradation or transcriptional inhibition (decrease in mRNA levels more than 6 hours from SDF-1 exposure). In vitro migration of ZAP70(+) CLL cells toward SDF-1 through a 5μm membrane (Migration Index [MI] of 12.0, n=5) was significantly increased compared to ZAP70(−) CLL cells (MI of 2.9, n=4, p<0.05). To exclude effects of contaminating cells we repeated these assays with purified CLL cells (negative selection) with similar results. To model the complex interactions of CLL cells with stroma, we cultured PB derived leukemic cells with or without murine marrow stroma cells (S17). CXCR4 expression on CD19+ cells decreased from 90% without S17 to 50% when cultured on S17 cells, consistent with the known SDF-1 secretion by the murine stroma cell line. Conversely, CD69 expression increased from 58% without S17 to 71% with S17 cells. In addition, culturing of CLL cells on an S17 stroma cell layer extended their survival by several weeks when compared to cultures without S17 cells. Our data is consistent with a model in which CLL cells migrate along an SDF-1 gradient to stroma cell niches in BM and LN where they are activated. ZAP70 expression is associated with more effective migration in an SDF-1 gradient and thereby may facilitate access to growth and survival signals which then could contribute to the more progressive nature of ZAP70(+) CLL. The interaction between leukemic cells and stroma may represent a novel target for therapy of patients with CLL.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3219-3219
Author(s):  
Gail A Dallalio ◽  
Robert T. Means

Abstract Abstract 3219 The anemia of chronic disease (ACD) is the major etiology of the anemia observed in in chronically ill patients. ACD typically manifests itself as a hypoproliferative anemia accompanied by a low serum iron concentration despite adequate reticuloendothelial iron stores. In ACD, a slight shortening of red cell survival creates a demand for a small increase in red cell production by the bone marrow. The marrow cannot respond adequately to this demand due to impaired erythropoiesis and impaired mobilization of reticuloendothelial system iron stores. Increased production of the iron regulatory peptide hepcidin has been proposed as the primary factor resulting in ACD. Hepcidin has also been reported to decrease erythroid colony formation in vitro under conditions of restrictive Epo concentration. A blunted erythropoietin (Epo) response to anemia is a characteristic feature of ACD. If hepcidin is the major factor responsible for ACD, then it should also contribute to the impaired Epo production observed in this syndrome. The effect of hepcidin on hypoxia-induced Epo production was evaluated in HepG2 cells exposed to 5% oxygen for 24 hr. 24 hr exposure to hepcidin during hypoxia at the concentrations studied (up to 100 ng/mL) had no adverse effect on HepG2 cell viability compared to controls as evaluated by cell number and Trypan blue exclusion or on cellular synthetic function as measured by alpha fetoprotein. Epo production (whether measured by Western blot or by ELISA) was increased by hypoxia; however, this increase was blunted by the addition of hepcidin to the incubation medium. Impairment of hypoxia-induced Epo production by hepcidin showed a dose-response relationship. The addition of iron-replete transferrin to the incubation mixture did not significantly alter hepcidin effects, suggesting that these effects do not primarily reflect changes in iron availability. In order to evaluate mechanisms by which hepcidin might decrease Epo production, effects of hepcidin 0–100 ng/mL on hypoxia-inducible factor (HIF)-1α protein expression were evaluated in HepG2 cells (HIF expression was normalized to actin expression). The increment in HIF-1α caused by hypoxia was decreased by hepcidin in a dose-dependent manner. The ratio of Epo to HIF was not altered by hepcidin, suggesting that hepcidin effects on HIF may be the mechanism of its effects on Epo production. In conclusion, hepcidin appears to blunt the increment in Epo production induced by hypoxia in vitro. This mechanism does not appear to be reversible by exposure to increased quantities of transferrin-bound iron. This finding is consistent with a role for hepcidin in the impaired Epo production of ACD independent of its effects on iron flux. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3895-3895
Author(s):  
Yair Herishanu ◽  
Inbal Hazan-Hallevi ◽  
Sigi Kay ◽  
Varda Deutsch ◽  
Aaron Polliack ◽  
...  

Abstract Abstract 3895 Chronic lymphocytic leukemia (CLL) cells depend on their microenvironment for proliferation and survival. Ectonucleotidase CD39 has anti-inflammatory properties as it hydrolyzes pro-inflammatory extra-cellular ATP, generates anti-inflammatory adenosine and also protects regulatory T cells from ATP-induced cell death. In this study we investigated the clinical significance of CD39 expression on CD4+T-cells in 45 patients with CLL as well as its compartmental regulation and explored the possible mechanisms for its induction. Compared to healthy individuals, CD4+CD39+ lymphocytes were increased in the peripheral blood of patients with CLL (4.6%±2.28 vs. 17.3%±12.49, respectively, p=0.004), and correlated with advanced stage of disease (9.72%±5.76, 18.15%±12.03 and 25.90%±16.34, of CD4+ lymphocytes, in patients with Rai stages 0, 1+2 and 3+4, respectively, p=0.019). CD4+CD39+ cells were also higher in patients with CLL who needed therapeutic intervention (untreated; 12.99%±10.63 vs treated; 22.21%±12.88, p=0.01) and in those who were ZAP70+ or had b2-microglobulin levels>3g/L. There were more CD4+CD39+ lymphocytes in the bone marrow compartment (22.25%±16.16) than in the peripheral blood (16.60%±15.84, p=0.009). In-vitro studies showed that CD39 can be induced on CD4+cells by exposure to ATP or indirectly, following B-cell receptor (BCR) engagement (CD4+CD39+ lymphocytes increased by 1.56 fold, in the BCR engaged samples compared to their paired controls; 20.27%±11.3 vs. 13%±9.42, respectively, p=0.0006). Conclusions: Increased CD39 expression on CD4+ T-lymphocytes in CLL associates with an aggressive disease. This may reflect the ability of the leukemic cells to suppress the surrounding immune environment, and contribute to a poorer prognosis. CD39+ may also serve as a future target for the development of novel therapies with immune modulating anti–tumor agents in CLL. Disclosures: No relevant conflicts of interest to declare.


Author(s):  
Bo Liang ◽  
Xudong Yuan ◽  
Gang Wei ◽  
Wei Wang ◽  
Ming Zhang ◽  
...  

AbstractTo curb the spread of SARS-CoV-2, the etiologic agent of the COVID-19 pandemic, we characterize the virucidal activity of long-acting Povidone Iodine (PVP-I) compositions developed using an in-situ gel forming technology. The PVP-I gel forming nasal spray (IVIEW-1503) and PVP-I gel forming ophthalmic eye drop (IVIEW-1201) rapidly inactivated SARS-CoV-2, inhibiting the viral infection of VERO76 cells. No toxicity was observed for the PVP-I formulations. Significant inactivation was noted with preincubation of the virus with these PVP-I formulations at the lowest concentrations tested. It has been demonstrated that both PVP-I formulations can inactivate SARS-CoV-2 virus efficiently in both a dose-dependent and a time-dependent manner. These results suggest IVIEW-1503 and IVIEW-1201 could be potential agents to reduce or prevent the transmission of the virus through the nasal cavity and the eye, respectively. Further studies are needed to clinically evaluate these formulations in early-stage COVID-19 patients.


1986 ◽  
Vol 51 (10) ◽  
pp. 2285-2290
Author(s):  
Jiří Veselý

Arabinosyl-5-azacytosine is phosphorylated by the L1210 mouse leukemic cells in vivo as well as by the cell-free extract in the presence of ATP. The drug inhibits in vitro the activity of DNA-dependent DNA polymerase α from L1210 cells in a dose-dependent manner but to a lesser degree than arabinosylcytosine. When administered in vivo, it depresses the activity of DNA polymerase to about the same extent as arabinosylcytosine. The Km constant for the phosphorylation of arabinosyl-5-azacytosine is 46% higher than the corresponding value for arabinosylcytosine.


2015 ◽  
Vol 7 (4) ◽  
Author(s):  
Romain Guièze ◽  
Emmanuel Gyan ◽  
Olivier Tournilhac ◽  
Christelle Halty ◽  
Richard Veyrat-Masson ◽  
...  

Chronic lymphocytic leukemia is an indolent disorder with an increased infectious risk remaining one of the main causes of death. Development of therapies with higher safety profile is thus a challenging issue. Docosahexaenoic acid (DHA, 22:6) is an omega-3 fatty acid, a natural compound of normal cells, and has been shown to display antitumor potency in cancer. We evaluated the potential <em>in</em> <em>vitro</em> effect of DHA in primary CLL cells. DHA induces high level of <em>in</em> <em>vitro</em> apoptosis compared to oleic acid in a dose-dependent and time-dependent manner. Estimation of IC50 was only of 4.813 μM, which appears lower than those reported in solid cancers. DHA is highly active on CLL cells <em>in vitro.</em> This observation provides a rationale for further studies aiming to understand its mechanisms of action and its potent <em>in vivo</em> activity.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2504-2504 ◽  
Author(s):  
Xia Tong ◽  
Georgios V. Georgakis ◽  
Long Li ◽  
O’Brien Susan ◽  
Younes Anas ◽  
...  

Abstract B-cell chronic lymphocytic leukemia (CLL) is characterized by in vivo accumulation of long-lived CD5+ B cells. However when cultured in vitro CLL cells die quickly by apoptosis. Protection from apoptosis in vivo is believed to result from supply of survival signals provided by cells in the microenvironment. We and others have previously reported that CLL cells express CD40 receptor, and that CD40 stimulation of CLL cells may rescue CLL cells from spontaneous and drug-induced apoptosis in vitro. These observations suggested that blocking CD40-CD40L pathway might deprive CLL cells from survival signals and induce apoptosis. To test this hypothesis, we have generated a fully human anti-CD40 blocking monoclonal antibody in XenoMousemice (Abgenix, Inc.). The antibody CHIR-12.12 was first evaluated for its effect on normal human lymphocytes. Lymphocytes from all 10 healthy blood donors did not proliferate in response to CHIR-12.12 at any concentration tested (0.0001 mg/ml to 10 mg/ml range). In contrast, activating CD40 on normal B-lymphocytes by CD40L induced their proliferation in vitro. Importantly, CHIR-12.12 inhibited CD40L- induced proliferation in a dose dependent manner with an average IC50 of 51 ± 26 pM (n=10 blood donors). The antagonistic activity of CHIR-12.12 was then tested in primary CLL samples from 9 patients. CHIR-12.12 alone did not induce CLL cell proliferation. In contrast, primary CLL cells incubated with CD40L, either resisted spontaneous cell death or proliferated. This effect was reversed by co-incubation with CHIR-12.12 antibody, restoring CLL cell death (n=9). CHIR-12.12 was then examined for its ability to lyse CLL cell line EHEB by antibody dependent cell mediated cytotoxicity (ADCC). Freshly isolated human NK cells from normal volunteer blood donors were used as effector cells. CHIR-12.12 showed lysis activity in a dose dependent manner and produced maximum lysis levels at 0.1 mg/ml. When compared with rituximab, CHIR-12.12 mediated greater maximum specific lysis (27.2 % Vs 16.2 %, p= 0.007). The greater ADCC by CHIR-12.12 was not due to higher density of CD40 molecules on CLL cell line compared to CD20 molecules. The CLL target cells expressed 509053 ±13560 CD20 molecules compared to 48416 ± 584 CD40 molecules. Collectively, these preclinical data suggest that CHIR-12.12 monoclonal antibody may have a therapeutic role in patients with CLL.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3919-3919
Author(s):  
Alfons Navarro ◽  
Tania Díaz ◽  
Antonio Martinez ◽  
Anna Gaya ◽  
Mariano Monzó

Abstract Abstract 3919 Background: The constitutive activation of the JAK/STAT pathway plays an important role in the pathogenesis and proliferation of Hodgkin Lymphoma (HL). Although somatic activating point mutations in the JAK2 gene have been reported in myeloproliferative disorders (MPD), they are rarely described in HL, where JAK2 amplification is associated with mutations of regulator genes such as SOCS-1, constitutive activation of STAT proteins or miRNA deregulation. Recently, many JAK2 inhibitors, including Lestaurtinib (CEP701), have been reported to have clinical efficacy in MPD. CEP701 is a multitargeted tyrosine kinase inhibitor that potently inhibits FLT3 at nanomolar concentrations. Recent studies in MPD have further shown that CEP701 inhibitory activity is not limited to FLT3 and can suppress JAK2/STAT5 signaling through JAK2 inhibition. As a first step towards elucidating the potential role of CEP701 in HL therapy, we have analyzed its efficacy in vitro. Methods: Four HL cell lines, L-428, L-1236, HDMYZ and L-540, were assayed for proliferation, apoptosis and levels of proteins in the JAK2/STAT pathway (pJAK2, JAK2, pSTAT5, STAT5, Bcl-xL) after CEP701 treatment. 100,000 cells were plated in a 96-well plate in 100 ml culture medium with CEP701 or DMSO (vehicle control) at concentrations of 30–300 nM. After 1 or 24 hours of incubation with CEP701, the levels of the proteins and of FLT3 were analyzed by Western blot. Proliferation was analyzed with CellTiter 96 AQueous One Solution Cell Proliferation Assay (MTS) and apoptosis by CaspaseGlo 3/7 after 48 hours of treatment. Results: The proliferation analysis showed an effective dose-dependent inhibition of cell growth in the 4 HL cell lines after treatment with increasing concentrations of CEP701. At 48h, in comparison to cells treated with DMSO alone (normalized to 100%), in cells treated with 100nM of CEP701, we observed a marked inhibition of 35% in L-428, 55% in L-1236, 15% in HDMYZ and 77% in L-540. Moreover, apoptosis increased by 38%, 31%, 21% and 25%, respectively. The protein analysis showed that after one hour, CEP701 inhibited phosphorylation of JAK2 (pJAK2) and its downstream target STAT5 (pSTAT5) in a dose-dependent manner, with no changes in the non-phosphorylated proteins. The downstream target Bcl-xL also decreased. Conclusions: Taken together, these data demonstrate that growth inhibition and apoptosis activation by CEP701 in HL cells correlates with the inhibition of the JAK2/STAT5-dependent signal transduction pathway. Here we present the first biological evidence that Lestaurtinib could be a promising new agent in the treatment of patients with HL. Supported by a FIS grant (PS09/00547). Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4627-4627
Author(s):  
Valentina Audrito ◽  
Tiziana Vaisitti ◽  
Sara Serra ◽  
Davide Rossi ◽  
Daniela Gottardi ◽  
...  

Abstract Abstract 4627 Nicotinamide (Nam), is the main precursor of nicotinamide adenine dinucleotide (NAD+). It regulates intracellular levels of NAD+ and consequently activities of four classes of NAD+-consuming enzymes, including NADases, mono-ADP-ribosyl transferases (ARTs), poly-ADP-ribose polymerases (PARPs) and sirtuins. Pharmacological doses of Nam inhibit the physiological activation and proliferation of mouse B lymphocytes, suggesting that this agent might affect also human B cell homeostasis. We approaches this issue by comparing the effects of Nam on normal vs. leukemic B lymphocytes. Chronic lymphocytic leukemia (CLL) was selected as disease model, for testing in vitro the therapeutic potential of Nam, due its intrinsic resistance to apoptosis, mediated by an imbalance in the mechanisms regulating cell death, mainly regulated through the activities of NAD+-dependent enzymes. This study shows that pharmacological doses of Nam (5-10 mM) significantly inhibit proliferation and induce apoptosis of CLL cells. At earlier time points, Nam markedly reduces phosphorylation of multiple intracellular substrates, including ERK1/2. Normal B lymphocytes, used as control, were significantly less sensitive to the action of Nam. We hypothesized that these effects could be explained at least in part as a consequence of the inhibitory effects of Nam on NAD+-consuming enzymes. Attention was focused on SIRT1, a deacetylase that plays a critical role in cancer and that acts as a longevity factor. The results demonstrate that Nam exposure inhibits the activity, and also the expression of SIRT1. This effect is apparent only in leukemic cells, where SIRT1 protein levels are significantly higher than in normal B lymphocytes, obtained from spleen or tonsils, markedly less sensitive to Nam effects. The functional block of SIRT1 induced by Nam is followed by activation of p53, transcription of miR-34a and translational repression of SIRT1 mRNA (p53/miR-34a/SIRT1 functional loop). The endpoint is the activation of apoptosis. The same loop is the target of conventional DNA-damaging drugs, such as etoposide. Thus, addition of Nam to conventional DNA-damaging chemotherapeutics agents, leads to an inhibition of SIRT1 through two independent and synergic pathways, resulting in additive effects on apoptosis. In conclusion this work suggests that Nam represents a potentially useful non-chemotherapeutic agent, characterized by a known and established safety profile, to be associated to conventional cytotoxic drugs in the treatment of selected forms of CLL. Disclosures: No relevant conflicts of interest to declare.


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