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A fraction of chronic lymphocytic leukaemia (CLL) cases carry highly homologous B-cell receptors (BCR), i.e. characterized by non-random combinations of immunoglobulin heavy-chain variable (IGHV) genes and heavy-chain complementarity determining region-3 (HCDR3), often associated with a restricted selection of IGVK/L light chains. Such 'stereotyped' BCR occur more frequently in CLL with unmutated (UM) than mutated (M) IGHV genes. We analysed 1426 IG rearrangements (from 1398 CLL cases) by a clustering driven by HCDR3 similarities. Molecular findings were correlated to time-to-treatment (TTT) and presence of known prognosticators. Sixty-nine clusters (319 IG-rearrangements, 22.4%) with stereotyped BCR were identified. Among 30 confirmed clusters (>or=3 IG-rearrangements/cluster), we found 14 novel clusters, of which 11 had M IG rearrangements (M clusters) and predominantly (8/11) used IGHV3 subgroup genes. Recurrent cluster-biased amino acid changes were found throughout IGHV sequences of these 'M clusters'. Regarding clinical outcome: (i) UM CLL from the IGHV1-2/1-3/1-18/1-46/7-4-1/IGKV1-39 cluster had poorer prognosis than UM/M cases, or UM cases using the same IGHV genes but not in clusters; (ii) M CLL from the IGHV3-21/IGLV3-21 cluster had TTT similar to UM CLL, and shorter than M CLL expressing IGHV3-21 but not in cluster. Altogether, our analysis identified additional molecular and clinical features for CLL expressing stereotyped BCR.

We have searched for gravitational waves from coalescing low mass compact binary systems with a total mass between 2 and 35 Msun and a minimum component mass of 1 Msun using data from the first year of the fifth science run (S5) of the three LIGO detectors, operating at design sensitivity. Depending on mass, we are sensitive to coalescences as far as 150 Mpc from the Earth. No gravitational wave signals were observed above the expected background. Assuming a compact binary objects population with a Gaussian mass distribution representing binary neutron star systems, black hole-neutron star binary systems, and binary black hole systems, we calculate the 90%-confidence upper limit on the rate of coalescences to be 3.9 \times 10^{-2} yr^{-1} L_{10}^{-1}, 1.1 \times 10^{-2} yr^{-1} L_{10}^{-1}, and 2.5 \times 10^{-3} yr^{-1} L_{10}^{-1} respectively, where $L_{10}$ is $10^{10}$ times the blue solar luminosity. We also set improved upper limits on the rate of compact binary coalescences per unit blue-light luminosity, as a function of mass., Comment: 15 pages, 5 figures, 2 tables; changes associated with referee comments, inclusion of recent LIGO calibration data, fixing small error in upper limit calculation

We present the results of a LIGO search for short-duration gravitational waves (GWs) associated with Soft Gamma Repeater (SGR) bursts. This is the first search sensitive to neutron star f-modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14 which occurred during the first year of LIGO's fifth science run. GW strain upper limits and model-dependent GW emission energy upper limits are estimated for individual bursts using a variety of simulated waveforms. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10^45 and 9x10^52 erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models., Comment: 6 pages, 1 Postscript figure

CD49d/α4-integrin is variably expressed in chronic lymphocytic leukemia (CLL). We evaluated its relevance as independent prognosticator for overall survival and time to treatment (TTT) in a series of 303 (232 for TTT) CLLs, in comparison with other biologic or clinical prognosticators (CD38, ZAP-70, immunoglobulin variable heavy chain (IGHV) gene status, cytogenetic abnormalities, soluble CD23, β2-microglobulin, Rai staging). Flow cytometric detection of CD49d was stable and reproducible, and the chosen cut-off (30% CLL cells) easily discriminated CD49dlow from CD49dhigh cases. CD49d, whose expression was strongly associated with that of CD38 (P < .001) and ZAP-70 (P < .001), or with IGHV mutations (P < .001), was independent prognosticator for overall survival along with IGHV mutational status (CD49d hazard ratio, HRCD49d = 3.52, P = .02; HRIGHV = 6.53, P < .001) or, if this parameter was omitted, with ZAP-70 (HRCD49d = 3.72, P = .002; HRZAP-70 = 3.32, P = .009). CD49d was also a prognosticator for TTT (HR = 1.74, P = .007) and refined the impact of all the other factors. Notably, a CD49dhigh phenotype, although not changing the outcome of good prognosis (ZAP-70low, mutated IGHV) CLL, was necessary to correctly prognosticate the shorter TTT of ZAP-70high (HR = 3.12; P = .023) or unmutated IGHV (HR = 2.95; P = .002) cases. These findings support the introduction of CD49d detection in routine prognostic assessment of CLL patients, and suggest both pathogenetic and therapeutic implications for CD49d expression in CLL.

BACKGROUND. Rituximab in sequential combination with fludarabine (Flu) allowed patients with B-cell chronic lymphocytic leukemia (B-CLL) to achieve higher remission rates and longer response duration. Based on their recent experience in indolent non-Hodgkin lymphomas, in this study, the authors attempted to demonstrate whether consolidation/maintenance therapy with rituximab could prolong the response duration in this patient population. METHODS. This Phase II study was based on a consolidation/maintenance therapy with rituximab for patients in complete remission (CR) or partial remission (PR) who were positive for minimal residual disease (MRD), as determined by flow cytometry. Seventy-five symptomatic, untreated patients with B-CLL received 6 monthly cycles of Flu (25 mg/m2 for 5 days) followed by 4 weekly doses of rituximab (375 mg/m2). Then, 28 patients who were positive for MRD were consolidated with 4 monthly cycles of rituximab (375 mg/m2) followed by 12 monthly low doses of rituximab (150 mg/m2). RESULTS. Based on National Cancer Institute criteria, 61 of 75 patients (81%) achieved a CR, 10 of 75 patients (13%) had a PR, and 4 of 75 patients (5%) had either no response or disease progression. MRD-positive patients in CR or PR who received consolidation therapy (n = 28 patients) had a significantly longer response duration (87% vs 32% at 5 years; P = .001) compared with a subset of patients who did not receive consolidation therapy (n = 18 patients). All patients experienced a long progression-free survival from the end of induction treatment (73% at 5 years). It was noteworthy that, within the subset of ZAP-70-positive patients, MRD-positive, consolidated patients (n = 12 patients) had a significantly longer response duration (69% vs 0% at 2.6 years; P = .007) compared with MRD-positive, unconsolidated patients (n = 11 patients). CONCLUSIONS. The addition of a consolidation and maintenance therapy withrituximab prolonged response duration significantly in patients with MRD-positive B-CLL. Cancer 2008. © 2007 American Cancer Society.

An aberrant pattern of expression of L-selectin and intercellular adhesion molecule 1 (ICAM1) may characterise CD34+ blast cells in myelodysplastic syndromes (MDS) and secondary acute myeloid leukaemia (sAML).In a three-colour flow cytometric assay, we evaluated the expression of L-selectin and ICAM1 on CD34+ blast cells from the bone marrow (BM) of 66 MDS patients; for the purpose of comparison CD34+ blast cells of 18 sAML and CD34+ stem cells of 17 normal donors were also analysed.The ratio of L-selectin/ICAM1 expression was identified as a parameter correlated with the percentage of BM blast infiltration and the time to leukaemic progression among MDS patients. In fact, the values of L-selectin/ICAM1 ratio were inversely correlated with the BM blast infiltration (r = -0.34, P = 0.004). Furthermore, MDS patients with a baseline ratio1 had a higher leukaemic progression rate (41% vs. 19%, P = 0.008); the actuarial risk of disease progression for this subgroup of MDS patients was also higher (64% vs. 11% at 2 yr, P = 0.002). Furthermore, in two patients a decrease of the ratio was observed when overt leukaemic transformation occurred; conversely, restoration of a normal ratio was observed in two patients after a chemotherapy-induced remission.(i) L-selectin is defective in the stem cell compartment of MDS and sAML, whereas ICAM1 is overexpressed; (ii) the ratio of their expression has a prognostic role; and (iii) a ratio1 significantly predicts progression to overt leukaemia in MDS patients.

To date, bone marrow (BM) is the most common source of cells to use in order to assess minimal residual disease (MRD) in acute myeloid leukemia (AML). In the present study, we investigated whether peripheral blood (PB) could be an alternative source of cells for monitoring MRD in AML.Fifty patients with AML were monitored for MRD after the achievement of complete remission. Using multiparametric flow cytometry we compared the levels of MRD in 50 and 48 pairs of BM and PB after induction and consolidation, respectively.After induction and consolidation therapy, the findings in BM and PB were significantly concordant (r=0.86 and 0.82, respectively, p0.001 for both comparisons). The cut-off value of residual leukemic cells in PB which correlated with outcome was 1.5x10 (-4). Thirty-three of 43 (77%) patients with1.5x10 (-4)residual leukemic cells in PB after induction had a relapse, whereas the seven patients with lower levels did not (p=0.0002). After consolidation, 38 patients had a level of MRD1.5x10 (-4)and 31 (82%) had a relapse; nine out of the remaining ten patients, whose levels of MRD were below 1.5x10 (-4), are still relapse-free (p=0.00006). In multivariate analysis, PB MRD status at the end of consolidation was found to have a significant effect on relapse-free survival (p=0.036).These preliminary results indicate that: (i) PB evaluation can integrate BM assessment for MRD detection in patients with AML; (ii) PB MRD status at the end of consolidation therapy may provide useful prognostic information.

Blood First Edition Paper, prepublished online December 5, 2006; DOI 10.1182/blood-2006-10-051110. IGHV3-21-using chronic lymphocytic leukemia (CLL) is a distinct entity with restricted immunoglobulin gene features and poor prognosis, more frequently encountered in Northern than Southern Europe. To further investigate this subset and its geographical distribution in the context of a country (Italy) with both continental and Mediterranean areas, 37 IGHV3-21 CLLs were collected out of 1076 cases enrolled by different Institutions from Northern or Central-Southern Italy. 18/37 cases, identified as homologous(hom)HCDR3-IGHV3-21 CLLs, were found almost exclusively (16/18) in Northern Italy, while 19 non-homHCDR3-IGHV3-21 cases were similarly distributed throughout Italy. Clinically, poor survivals were documented for IGHV3-21 CLLs as well as for subgroups of mutated and homHCDR3-IGHV3-21 CLLs. Negative prognosticators CD38, ZAP-70, CD49d, CD79b were expressed at higher levels in homHCDR3 than non-homHCDR3-IGHV3-21 cases. Differential gene expression profiling (GEP) of 13 IGHV3-21 vs. 52 non-IGHV3-21 CLLs, identified, among 122 best-correlated genes, TGFB2 and VIPR1 as down- and up-regulated in IGHV3-21 CLL cases, respectively. Moreover, GEP of 7 homHCDR3 vs. 6 non-homHCDR3-IGHV3-21 CLLs yielded 20 differentially expressed genes, WNT16 being that expressed at the highest levels in homHCDR3-IGHV3-21 CLLs. Altogether, IGHV3-21 CLLs, including those with homHCDR3, had a peculiar global phenotype in part explaining their worse clinical outcome.

INTRODUCTION. Resistance to carbapenems by Klebsiella pneumoniae (KP) isolates has become a significant problem in recent years in several countries, and has been recently highlighted as one of the major emerging causes of severe and fatal infections in patients suffering from hematological malignancies (HM). The aim of the present study was to identify risk factors for mortality in HM patients with concurrent bloodstream infections (BSIs) caused by KP. Particular attention was focused on defining the impact of carbapenem resistance by the bacterial isolates on mortality. METHODS. We conducted a prospective cohort study including all consecutive cases of BSIs caused by KP diagnosed in 13 Italian hematological units participating to HEMABIS registry-SEIFEM group. The outcome measured was death within 30 days of the first positive blood culture. Survivor and non-survivor subgroups were compared, and logistic regression analysis was conducted to identify independent predictors of mortality. RESULTS. A total of 278 episodes of KP BSI were included in the study between January 2010 and June 2014. One hundred-sixty-one (57.9%) KP isolates were carbapenem resistant (CRKP). The rate of carbapenem resistance among KP isolates significantly increased from 21.4% in 2010 to 75.9% in 2013 (P In multivariate analysis, significant predictors of mortality were septic shock (OR 17.34, 95% CI 6.65-45.23; P CONCLUSIONS. Carbapenem resistance has dramatically emerged during the last years as the most frequent and fatal cause of BSI among KP isolates in HM patients in Italy. Although further studies to better define epidemiology and clinical impact of these infections are needed, the efficacy of therapeutic treatment protocols for HM patients could be probably improved through the sound knowledge of the local distribution of KP isolates and their susceptibility patterns and judicious use of antibiotics and control measures to prevent the development and spread of CRKP. Disclosures No relevant conflicts of interest to declare.

Differences in tumor proliferation and apoptosis levels explain the heterogeneous clinical course of CLL reflecting both genetic differences and the activity of external signals mainly through the B-cell receptor pathway (Herishanu et al, Blood, 2011; Rossi et al, Blood, 2013). Therefore high dynamic proliferation rate and impaired apoptosis represent crucial mechanisms both in the chemoresistance and in the progressive disease (Messmer et al, J Clin Invest 2005; Cervantes-Gomez et al, Clin Cancer Res, 2015). The today availability in clinical use both of ibrutinib, a potent Bruton tyrosine kinase (BTK) inhibitor, which blocks cell proliferation and trafficking (Cheng S et al, Leukemia, 2013; Burger et al, Blood, 2014) and venetoclax (ABT-199), a novel potent oral anti-bcl-2 peptidomimetic (Seymour et al, J Clin Oncol, 2014) as well as their possible synergistic combination (Portell et al, Blood, 2014), prompted us to analyze the real impact of the proliferative rate (Ki67 percentages) and the apoptosis (bax/bcl-2) on CLL prognosis. The primary aims of our research were: 1) to correlate Ki67 and bax/bcl-2 with clinical and biological prognostic factors; 2) to determine progression free survival (PFS) and overall survival (OS) upon Ki67 and bax/bcl-2; 3) to evaluate Ki67 and bax/bcl-2 as independent prognosticators. Therefore we investigated 606 patients, median age 66 years (range 33-89), 340 males and 266 females. With regard to modified Rai stages at diagnosis, 220 patients had a low stage, 369 an intermediate stage and 17 a high stage. Ki67 was evaluated by flow cytometry in terms of percentages of CD19+CD5+ CLL cells and the threshold of positivity was set at >5% (range 0.10-22.7). Also bax/bcl-2 was calculated by flow cytometry, dividing mean fluorescence intensity (MFI) of bax by MFI of bcl-2 on CLL cells. The threshold was set at the median value >1.5 (range 0.27-6.10). One hundred-ten patients were Ki67+ (18.2%) and 321 were bax/bcl-2+ (53%). Both higher Ki67 and lower bax/bcl-2 were significantly associated with intermediate/high Rai stage, beta-2 microglobulin (B2M)>2.2 mg/dl and soluble CD23>70 U/ml (P1.5 plus Ki671.5/Ki67>5%) showed an intermediate outcome (67% and 63% at 12 years, respectively, Figure). In multivariate analysis of OS (593 patients), bax/bcl-2 ratio (P=0.004) and Ki67 (P=0.02) together with age (P=0.0002), B2M (P=0.005), cytogenetics (P=0.003), IGHV status (P=0.0005) and TP53 (P=0.0006) were confirmed as independent prognostic factors. Therefore, both the proliferative marker Ki67 and the apoptotic index bax/bcl-2, performed by flow cytometry, are powerful prognosticators showing synergistic clinical effects. Experiments of apoptosis, proliferation and trafficking testing ABT-199 and ibrutinib on CLL cells in vitro are in progress at our Institutions (Gattei et al, unpublished data). In conclusion, the modern treatment strategies in CLL should aim to block proliferation and trigger apoptosis concurrently (i.e. ibrutinib and venetoclax) in order to achieve longer overall survival. Figure 1. Figure 1. Disclosures No relevant conflicts of interest to declare.

Introduction: Incidence of fungal infections is reducing in the last years due to wider use of effective antifungal prophylaxis. On this basis, we evaluated clinical characteristics and outcome of patients (pts) with hematological malignancies (HMs) and fungal bloodstream infections (FBSI). Patient and Methods: This retrospective/prospective study gathered consecutive documented FBSI observed among HMs diagnosed between January 2011 and June 2015 in 19 Italian Hematology Departments that refer to SEIFEM (Sorveglianza Epidemiologica Infezioni Fungine Emopatie Maligne) group. Results: We collected overall 100 patients including retrospective pts and those observed in the first six months of the prospective study with FBSI among 16 centers; further 3 centers reported no cases of FBSI. Regarding patients' characteristics male/female ratio was 1, median age was 55 yeras. (IQR 18-88). Two-third of FBSI were detected in AML (43 - 43%) and NHL (27 - 27%); the remaining pts were affected by ALL (9 - 9%), MM (6 - 6%), MDS (5 - 5%), MDS/MPN (5 - 5%), CLL (3 - 3%) and HL (2 - 2%). Thirty-five pts had FBSI at the onset of HM or after the first induction, 47 after treatment for refractory/relapsed disease, 13 when in remission, 28 pts during transplant procedures (17 from allogeneic donor, 11 from autologous cells). Fifty-nine pts were receiving antifungal prophylaxis at FBSI breakthrough: 26 posaconazole, 16 fluconazole, 6 itraconazole, 3 amphotericin B, 3 caspofungin, 1 voriconazole, and 4 combination of amphotericin B/azoles; 4 pts were treated with secondary prophylaxis after previous fungal infection. Eighty-nine pts had a central venous catheter. Eighty-four pts presented a neutrophils count < 500/mmc for a median time of 7 days before FBI onset (0-70 d); 50 pts received steroids and other 17 immunosuppressive treatment for allo-HSCT. Yeasts were the most common agent detected. Candida spp. represent the most represented yeast, counting for 77% of all infections; (21 albicans and 56 non albicans); 8% of FBI were due to 8% Geotrichum, 3% Trichosporon and 2% Rhodotorula, Molds were rare but not infrequent: 8% were caused by Fusarium and 1% by Scedosporium. Three patients died before starting any antifungal. Fifty-two received echinocandins (49 caspofungin and 3 anidulafungin), 22 liposomal amphotericin B (L-AmB), 15 azoles (7 fluconazole, 3 posaconazole, 3 voriconazole and 2 itraconazole) and 8 pts combo therapy (5 posa+L-AmB, 2 Caspo+L-AmB, 1 vori+caspo). Thirty-eight pts died within 30 days from FBSI diagnosis, 28 (74%) of whom due to infection. Among these 12 (43%) suffered from AML (1 in induction, 1 in CR, 10 had refractory/relapsed disease), 2 (7.2%) from ALL (all with refractory/relapsed disease), 7 (25%) from NHL (2 in induction, 2 in CR, 3 with refractory/relapsed disease), 4 (14%) from refractory/relapsed MM, 1 (3.6%) from MDS in remission, 2 (7.2%) from newly diagnosed MDS/MPN. In 8 pts (21%) for whom we cannot discriminate if death was subsequent to FBSI only or to uncontrolled HMs, fungal isolates were all rare yeast or molds except 2. Mortality was related only with advanced phase of underlying HM (p Conclusions: Nowadays FBSI represents a rare complication of HMs, as a consequence of wider availability of effective antifungal prophylaxis. Candidemia still represents the most important cause of FBSI, although about 25% of FBSI are due to rare yeast or molds. Regardless a lowering incidence, the observed mortality remains high even with target treatment. Disclosures No relevant conflicts of interest to declare.

Despite advances in treatment and supportive therapies, outcome of acute myeloid leukemia (AML) remains dismal with approximately 40% of younger and less than 20% of elderly patients becoming long-term survivors. Stem cell transplantation (SCT) is a well-established post-remission therapeutic option, and in both its variants, autologous (AuSCT) and allogeneic (ASCT), it is often incorporated in modern treatment programs for it may reliably improve long-term prognosis. Ten years ago we demonstrated that the levels of minimal residual disease (MRD) before autologous stem cell transplant (AuSCT), assessed at the post-consolidation time point by multiparametric flow cytometry (MFC), affected outcome (1). Moreover, we have preliminarily observed that in MRD positive (MRDpos) patients, allogeneic stem cell transplant (ASCT) attenuates the negative prognostic impact of pre-transplant MRD positivity by conferring a significant survival advantage in terms of either overall (OS) or disease free survival (DFS) (2). At variance with this, others have shown that even in the setting of ASCT, pre-transplant MRD positivity is associated with a poor prognosis regardless of the graft-versus-leukemia (GVL) effect (3). The aim of the present analysis was to evaluate, in 81 MRDpos patients submitted to ASCT (45) or AuSCT (36), the impact on clinical outcome of different MRD levels. As previously reported, counting 3.5x10-4 (0.035%) residual leukemic cells (RLCs) or more in the bone marrow (BM) upon full hematological recovery after consolidation cycle, was regarded as a condition of MRD positivity. Patients with or above 3.5x10-4 RLC were arbitrarily divided into 3 different cohorts: 1) ≥0.035%≤0.1% (13 patients, 6 ASCT and 7 AuSCT); 2) >0.1%≤1% (52 patients, 31 ASCT and 21 AuSCT); 3) >1% (16 patients, 8 ASCT and 8 AuSCT). In the category no. 2, ASCT gave a significant 5-years OS (64,9% vs 17,9%, p1%) MRD positive patients, ASCT does not guarantee a long-term control of leukemia and further reduction of relapse risk is expected to be facilitated by novel strategies. Disclosures No relevant conflicts of interest to declare.

Acute myeloid leukemia (AML) is a disease with a poor outcome and novel approaches are needed to improve survival and decrease toxicity of current therapies. Bst1/CD157 is a protein belonging to the ADP-ribosyl-cyclase family expressed on monocytes and neutrophils. This antigen was shown to be also expressed in peripheral blood (PB) and bone marrow (BM) blasts of acute myeloid leukemia (AML) patients either at primary diagnosis or at relapse(1,2,3). MEN1112/OBT357 is a humanized, de-fucosylated antibody targeting Bst1/CD157 with high affinity and developed to generate antibody dependent cell-mediated cytotoxicity (ADCC) response against AML blasts. Peripheral blood (PB) and bone marrow (BM) samples of 38 AML patients (29 at diagnosis, 6 at relapse, 3 resistant), have been analyzed for the expression of Bst1/CD157 on AML blast cells by fluorescence-activated cell sorting (FACS) using a PE conjugated form of MEN1112/OBT357. Bst1/CD157 expression has been confirmed in 91% and 96% of PB and BM AML samples, respectively. Furthermore, statistical analysis demonstrated that monocyte-oriented blasts are characterized by a brighter expression of Bst1/CD157 compared to blasts of non-monocytic lineage. The efficacy of MEN1112/OBT357 in depleting AML blasts was evaluated through FACS analysis in an autologous ex vivo assay performed on whole blood. The assay was set up using blood from healthy donors exposed to 10 μg/ml Rituximab for 18 hours to induce B cell depletion. In the same conditions, the ability of 10 μg/ml MEN1112/OBT357 to induce blasts depletion was tested.In whole PB,MEN1112/OBT357 was able to deplete AML blasts in 15/32 evaluable cases (46%). In BM, MEN1112/OBT357 induced blast depletion in 9/24 evaluable cases (36%). Interestingly, higher depletion rate was observed in relapse/refractory patients. When CD16A-158Phe/Val polymorphisms were analyzed utilizing a sequence based typing (SBT) assay, it was demonstrated that AML blast depletion was independent by FcRg polymorphism. Furthermore, no significant shedding of Bst1/CD157 antigen was observed in sera from AML patients, compared to the sera from patients with other hematologic diseases or healthy donors. In summary, we confirmed the frequent expression of Bst1/CD157 on blasts from AML patients, with the brightest pattern of positivity observed in cases belonging to monocytic differentiation lineage. MEN1112/OBT357 also induced a promising ADCC against AML blasts in an autologous setting, which is independent from FcR g phenotype. Since in vivo the exposure of AML blasts to MEN1112/OBT357 largely exceeds the incubation time of the depletion assay, we expect a further improvement of its anti-leukemic effect in the clinical setting. Based on these results, a phase I study in patients with relapsed or refractory AML has been initiated in December 2014. Disclosures Bellarosa: Menarini Ricerche: Employment. Bressan:Menarini Ricerche: Employment. Wilson:Oxford Biotherapeutics: Employment. Manzini:Menarini Ricerche: Employment. Capriati:Menarini Ricerche SpA: Employment. Simonelli:Menarini Ricerche SpA: Employment. Binaschi:Menarini Ricerche: Employment.

Allogeneic leukemia and cancer epithelial (CE) cells have been recently shown to induce,in vitro, NK cell abnormalities (NKCA). The latter include NK cell depletion and apoptosis as well as natural cytotoxic receptor (NCR) CD16 down-regulation. The potential negative impact of leukemia and CE cell induced NKCAs on the in vivo anti-tumor activity of NK cells and the limited information about strategies to protect NK cells from NKCAs have prompted us to characterize NKCAs and to develop strategies to counteract them. NKCA induction by leukemia and CE cells is influenced neither by interleukin-2 (IL-2) treatment nor by HLA class I antigen expression, but is abrogated by a long term culture of peripheral blood mononuclear cells (PBMCs) at 37 ºC. Following a 10 day culture of PBMCs, NK cells become resistant to cancer cell induced NKCA but maintain their cytotoxic activity. Actinomycin D restores the susceptibility of long term NK (LTNK) cells to NKCAs suggesting that the generation of resistance to NKCAs requires RNA transcription. TAPI-0, a functional analogue of the tissue inhibitor of metalloproteinases (TIMP) 3, inhibits cancer cell induced NKCAs indicating a role for a restricted number of metalloproteinases (MMPs) in the generation of this phenomenon. This conclusion is supported by the reduced susceptibility to cancer cell induced NKCAs of LTNK cells in which TIMP3 gene and protein are over-expressed. Finally, subcutaneous infusion of IL-2 stimulated LTNK cells inhibited subcutaneous growth of the monoblastic leukemia cells, ML-2 in CB17scid mice while short term, IL-2 stimulated NK cells did not suggesting that LTNK cells have significant anti-leukemia capacity in vivo. This information may contribute to the rational design of targeted strategies to enhance the efficacy of NK cell-based-immunotherapy for the treatment of myeloid leukemias with haploidentical or allogeneic NK cells. Citation Format: Giuseppe Sconocchia, Roberto Arriga, Sara Caratelli, Giulia Lanzilli, Andrea Coppola, Giulio C. Spagnoli, Adriano Venditti, Sergio Amadori, Davide Lauro, Maria I. Del Principe, Luca Maurillo, Francesco Buccisano, Barbara Capuani, Xinhui Wang, Soldano Ferrone. Association of long term NK cell culture and TIMP3 over-expression with NK cell reduced susceptibility to leukemia and epithelial cancer cell induced damage. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4050. doi:10.1158/1538-7445.AM2015-4050

Background: Expression of T cell specific zeta-associated protein 70 (ZAP-70) by B-cell chronic lymphocytic leukemia (B-CLL) cells, as investigated by flow cytometry, has both prognostic relevance and predictive power as surrogate for immunoglobulin heavy chain variable region (IgVH) mutations, although a standardization of the cytometric protocol is still lacking. Methods: Flow cytometric analyses for ZAP-70 were performed in peripheral blood samples from 145 B-CLL (124 with IgVH mutations) by a standard three-color protocol. Identification of ZAP-70+ cell population was based on an external negative control, i.e., the isotypic control (ISO method) or an internal positive control, i.e., the population of residual normal T/NK cells (TNK method). A comparison between these two approaches was performed. Results: While 86/145 cases were concordant as for ZAP-70 expression according to the two methods (ISO+TNK+ or ISO−TNK−), 59/145 cases had discordant ZAP-70 expression, mainly (56/59) showing a ISO+TNK− profile. These latter cases express higher levels of ZAP-70 in their normal T cell component. Moreover, discordant ISO+TNK− cases had a IgVH gene mutation profile similar to that of concordantly positive cases and different from ZAP-70 concordantly negative B-CLL. Conclusion: Analysis of ZAP-70 expression by B-CLL cells by using the ISO method allows to overcome the variability in the expression of ZAP-70 by residual T cells and yields a better correlation with IgVH gene mutations. A receiver operating characteristic analysis suggests to employ a higher cut-off than the commonly used 20%. A parallel evaluation of the prognostic value of ZAP-70 expression, as determined according to the ISO and TNK methods, is still needed. © 2006 International Society for Analytical Cytology

We have previously identified 12 surface antigens whose differential expression represented the signature of B-cell chronic lymphocytic leukemia (B-CLL) subsets with different prognosis. In the present study, expression data for these antigens, as determined in 137 B-CLL cases, all with survivals, were utilized to devise a comprehensive immunophenotypic scoring system of prognostic relevance for B-CLL patients. In particular, univariate z score was employed to identify the markers with greater prognostic impact, while maximally selected log-rank statistics were chosen to define the optimal cut-off points capable to split patients into two groups with different survivals. A weighted immunophenotypic scoring system was developed by integrating results from these analyses. Six antigens were selected: three positive prognosticators (CD62L, CD54, CD49c) and three negative prognosticators (CD49d, CD38, CD79b), with cut-off values ranging from 30% to 50% of positive cells. By weighing the expression of each marker according to its statistical power, a complete scoring system, with point values comprised between 0 (complete absence of phenotypic conditions associated with good prognosis) and 9 (all the phenotypic conditions associated with good prognosis fulfilled), allowed to split the whole set of B-CLL patients, into three distinctive prognostic groups (P = 4.78 x 10(-11)) with high- (score 0-3), intermediate- (score 4-6), and low- (score 7-9) risk of death. The three risk groups showed different distribution of cases as for Rai's stages, IgVH mutations, and ZAP-70 expression. The proposed immunophenotypic scoring system may be an additional useful tool in routine diagnostic/prognostic procedures for B-CLL.

The primary cause of treatment failures in acute myeloid leukemia (AML) is the emergence of both resistant disease and early relapse. Among the most frequent agents of these phenomena are defects in the mitochondrial-mediated apoptotic pathway. This pathway is regulated by bcl-2 family of anti-apoptotic (bcl-2, bcl-xl, mcl-1) and pro-apoptotic proteins (bax, bad, bak). In particular, bcl-2 dimerizes with several members of bcl-2 family of proteins, altering the threshold of cell death. The flow cytometric quantitative measurement of bcl-2 and bax expression for the determination of bax/bcl-2 ratio provided crucial clinical information in AML: in our hands, lower bax/bcl-2 ratio conferred a very poor prognosis with decreased rates of complete remission (CR) and overall survival (OS). Moreover, striking correlations were found between lower bax/bcl-2 ratio and higher progenitor marker expression, such as CD34, CD117 and CD133 antigens, confirming the link between this apoptotic index and the maturation pathways. However, the capacity of bax/bcl-2 ratio to clearly identify patients with different prognosis with regard to CR and OS within the CD34+, CD117+ and CD133+ subgroups implies that other mechanisms, such as proliferation and/or cell cycle dysregulation may be involved to explain its clinical significance. Finally, small molecules that target both the receptor- and mitochondrial-mediated pathway of apoptosis are providing encouraging results in patients with relapsed and/or refractory disease (i.e. CDDOMe, bcl-2 antisense oligonucleotides, CEP-701, etc), confirming the key role of apoptotic mechanisms on the outcome of AML patients.

Clinical trials of monoclonal antibodies in combination with chemotherapy have reported previously unattained response rates in patients with B-cell chronic lymphocytic leukemia (B-CLL); however, the analysis of ZAP-70 protein and/or CD38 may explain better the discordant outcomes independent of treatment.The authors conducted a Phase II study, in which rituximab was added to fludarabine for patients with symptomatic, untreated CLL, to evaluate clinical outcomes. Sixty patients with B-CLL received 6 monthly courses of fludarabine (25 mg/m(2) for 5 days) followed by 4 weekly doses of rituximab (375 mg/m(2)).On the basis of National Cancer Institute criteria, 47 of 60 patients (78%) achieved a complete remission, 9 of 60 patients (15%) achieved a partial remission, and 4 of 60 patients (7%) had no response or progressive disease. It is noteworthy that the patients experienced a long progression-free survival (PFS) from treatment (68% at 3 yrs). A significantly shorter PFS was observed in ZAP-70-positive patients (25% vs. 100% at 3 yrs; P = 0.00005), in CD38-positive patients (18% vs. 91% at 3 yrs; P = 0.0002), and in patients who had more minimal residual disease (36% vs. 77% at 2.5 yrs; P = 0.001).With the addition of rituximab to fludarabine, improved clinical outcomes were obtained, and the stratification of patients by using ZAP-70 and CD38 may help clinicians offer more aggressive and/or experimental approaches to the treatment of patients with high-risk B-CLL subtypes.

p53 status and CD38 antigen are biological factors influencing response to therapy and clinical course in B-cell chronic lymphocytic leukemia (B-CLL). This study tests the hypothesis that soluble p53 alone and in association with CD38 can enucleate B-CLL subsets at worse prognosis.Wild and mutant forms of p53 protein were evaluated in 197 B-CLL patients at diagnosis or before progression by an immunoenzymatic method in plasma using an anti-p53 monoclonal antibody. CD38 expression was analyzed by a multicolor flow cytometric assay.Higher levels of both soluble p53 (sp53) and CD38 were significantly correlated with intermediate and high Rai stages, with higher beta2-microglobulin and soluble CD23 values, determined at diagnosis. Shorter overall survival (OS) and progression-free survival (PFS) were both observed in sp53+ and CD38+ patients (p0.0001). Simultaneous positivity or negativity for sp53 and CD38 identified two subsets of patients, the former with a worse prognosis and the latter with a better prognosis with regard to PFS (p0.0001) and OS (p0.0001). The predictive value of sp53 and CD38 was retained among the patients within the intermediate Rai risk group.sp53 and CD38 together with ZAP-70 were confirmed to be independent prognostic factors in multivariate analysis. With regard to PFS, ZAP-70, sp53 and CD38 were confirmed to be independent prognostic factors. Concerning OS, ZAP-70, CD38 and age (or60 years) were independent prognostic factors whereas sp53 showed only a tendency towards statistical significance.

The objective of this study was to investigate the expression of MDR1 and bcl-2 proteins in de novo acute myeloid leukemia (AML).The expression of MDR1 and bcl-2 was analyzed by flow cytometry in a large series of 256 consecutive cases of AML. The results were recorded as percentage of positivity and relative mean fluorescence intensity (rMFI). To determine individual protein levels, an index which equals the product of the percentage of positive cells and rMFI was generated.Using cut-offs ofor=800 and 300 of the index value for bcl-2 and MDR1 expression, respectively, we identified 4 different classes of AML: 1) double negative; 2) single positive bcl-2+/MDR1-; 3) single positive bcl-2-/MDR1+; 4) double positive. The highest incidence of double negative cases was observed in the M2 class whereas double positive cases occurred more frequently in the M4, M5 and M6 subgroups. Seventy-eight percent and 71% of M0 and M1, respectively, showed single positive bcl-2+/MDR1- expression (p = 0.00001). Twenty-eight percent of patients belonging to the double positive category achieved complete remission, whereas for double negative, single positive bcl-2+MDR1- and single positive bcl-2-/MDR1+ category, the complete remission rate was 69%, 52% and 56%, respectively (p = 0.00038). In multivariate analysis, the double positive status independently affected frequency of complete remission (p = 0.008).Bcl-2 is over-expressed in CD34+ AML; conversely, MDR1 is over-expressed in CD34- AML. However, the combined expression of the two proteins defines a subset of AML with a very poor prognosis.

Concurrent resistance mechanisms, such as P-glycoprotein (PGP) and bcl-2, may contribute to a worse outcome in adult acute lymphoblastic leukaemia (ALL). Between 1990 and 2000, we analysed PGP and bcl-2 by flow cytometry, using two anti-PGP (C219 and JSB-1) monoclonal antibodies (mAbs) and an anti-bcl-2 mAb in 115 de novo adult ALL patients. Both a longer overall survival (OS) and longer disease-free survival (DFS) were observed in PGP-negative patients (23%vs 0% at 3 years, P = 0.011 and 29%vs 0% at 2 years, P = 0.006 for C219 respectively; 42%vs 0% at 1.5 years, P = 0.004 and 53%vs 0% at 8.5 months, P = 0.00006 for JSB-1 respectively). Bcl-2 positivity was associated with a significantly higher complete remission rate (90%vs 66%, P = 0.01). Moreover, in 69 patients not presenting with either t(9;22) or B-mature immunophenotype, PGP negativity (JSB-1) maintained its significant favourable prognostic impact with regard to OS (41%vs 0% at 1.5 years, P = 0.009) and DFS (83%vs 0% at 6 months, P = 0.0005). Importantly, within a subset of 62 patients with normal (n = 31) or unknown (n = 31) karyotype, PGP (JSB-1)-negative patients showed both a significantly longer OS and DFS (63%vs 0% at 1.4 years, P = 0.018 and 84%vs 0% at 6 months, P = 0.001 respectively). In multivariate analysis, JSB-1 (P = 0.008) and cytogenetics (P = 0.02) were found to be independent prognostic factors with regard to DFS. Therefore, in adult ALL, PGP and bcl-2 represent sensitive indicators of clinical outcome, and potential targets of novel molecules aimed at overcoming chemoresistance and recurrent relapses.

The inability to undergo apoptosis is a crucial mechanism of multidrug resistance in acute myeloid leukemia (AML), and the analysis of mitochondrial apoptotic proteins may represent a significant prognostic tool to predict outcome. Bcl-2 and Bax oncoproteins were evaluated in 255 de novo AML patients (pts) by flow cytometry using an anti–bcl-2 monoclonal antibody (MoAb) and an anti-bax MoAb. The results were expressed as an index (bax/bcl-2) obtained by dividing bax mean fluorescence intensity (MFI) and bcl-2 MFI. Lower bax/bcl-2 ratio was associated with French-American-British (FAB) M0-M1 classes (P = .000 01) and CD34 more than 20% (P

Multiparametric flow cytometry (MPFC) detection of minimal residual disease (MRD) represents a robust surrogate for the quality of complete remission (CR) and reliably predicts clinical outcome. In our experience, MRD detection provides prognostically relevant information when assessed at the post-consolidation time point. Ten years ago we demonstrated that the amount of MRD before autologous stem cell transplant (AuSCT) affected outcome. More recently, other authors have extended this observation to allogeneic stem cell transplant (ASCT) showing that pre-transplant MRD is a major determinant of prognosis regardless of graft-versus-leukemia (GVL) effect. The aim of our study was to evaluate, in an extended series of patients submitted to AuSCT or ASCT, the impact of a pre-transplantation MRD positive (MRDpos) or negative (MRDneg) status on overall survival (OS) and disease free survival (DFS). We analyzed 173 MRDpos and 53 MRDneg patients of whom 67 were submitted to AuSCT and 51 to ASCT. Eighty-two patients received no transplant because of age, poor performance status or insufficient stem cell harvest whereas 26, all in the MRDpos group, relapsed before transplant delivery. In the AuSCT group, before transplant, 32/67 (48%) were MRDneg and 35/67 (52%) MRDpos, with MRDneg group showing a superior OS (55% vs 20%, p=0.007). In the ASCT group, before transplant, 45/51 (88%) were MRDpos and 6/51 (12%) MRDneg. For 21 out of 51 (41%) sources of stem cells were matched unrelated donors (12) or haploidentical donors (9). In this subgroup, MRDpos and MRDneg patients shared a comparable 5-years OS (60% vs 56%, p=NS), with a 36% survival gain for those MRDpos who received ASCT as compared to AuSCT. Among MRDneg patients, no survival differences were demonstrated between those submitted to AuSCT or ASCT (55% vs 60%, p=NS). Such a lack of difference is likely due to the higher treatment related mortality (ASCT 3/6, 50% vs AuSCT 2/32, 6%, p=0.003) which counterbalanced the lower relapse rate in the ASCT group (ASCT 0/6, 0% vs AuSCT 11/32, 34%, p=NS). In conclusion, ASCT confers a significant survival advantage to MRDpos patients, attenuating the negative prognostic impact of pre-transplant MRD positivity. ASCT may expose MRDneg patients to an excess of toxicity suggesting that in these patients the allogeneic option should be postponed after a second remission. In MRDpos patients, AuSCT does not represent a valid therapeutic choice and ASCT, which should be timely delivered, also considering alternative sources of stem cells. Disclosures No relevant conflicts of interest to declare.

Bendamustine has been demonstrated to be effective for the treatment of CLL, either alone compared with chlorambucil (Knauf et al, JCO 2009 and BJH 2012) or in combination with monoclonal antibodies such as rituximab both in second or more lines (Fischer et al, JCO 2011) and in first line treatment (Fischer et al, JCO 2012). However, the relationship between its activity with clinical and biological prognosticators has been addressed only in few studies. For this purpose, we evaluated the efficacy and safety of bendamustine, in a real-life contest, on 56 patients, median age 66 years (41-80), median number of previous regimens 1 (0-3, 32% previously untreated). Bendamustine was given for a median number of 6 cycles (70-90 mg/m2), in 82% of cases with rituximab at conventional doses. Overall (ORR) and complete response (CRR) rates were 73% and 44.6%, respectively. Obviously, CRR was higher (83.3%) for 18 patients treated in first line. A significant correlation was found between lower ORR and lymphocyte doubling time 30%) of alpha-4 integrin CD49d (OR 13.0; P=0.018), an important marker of bad prognosis in CLL (Bulian et al, JCO 2014). On the other hand, no significant correlations were found between ORR and CD38, ZAP-70 or IGHV mutational status. Similarly, no significant correlations were noted between ORR and FISH cytogenetics, excluding del(17)p, or NOTCH1 mutations, thus confirming the independence of response to bendamustine from some well-known important biologic prognostic factors. In fact, multivariate analysis confirmed a significant relationship only between ORR and TP53/del(17)p (OR 0.020; P=0.0015) and concomitant rituximab (OR 0.019; P=0.0074). The estimated 1-year OS and PFS were 57% and 86%, respectively. Side effects included grade 3-4 neutropenia, infections, thrombocytopenia and anemia which occurred in 21%, 12%, 12% and 5% of patients, respectively. Grade 3-4 non-hematologic toxicity, including infusion-related reactions, heart or kidney or liver failure were found almost exclusively in elderly patients treated with bendamustine after two or more lines of therapy (12.5%). In multivariate analisys of OS, calculated from the end of treatment with bendamustine, only response to bendamustine (P=0.008) was confirmed to be an independent prognostic factor, while both the number of previous therapies and the concomitant use of rituximab demonstrated no statistical significance. These our results confirm both the activity and safety of bendamustine, particularly in combination with rituximab, also in the setting of elderly patients, often affected by two or three comorbidities. Noteworthy, this effectiveness appears to be present also in patients with unfavorable clinical and biological features, excluding del(17)p or TP53 mutations, in which the employment either of modern oral BCR inhibitors or of BH3 mimetics anti-Bcl-2 will be definitely active, also in combination with the same bendamustine. Disclosures No relevant conflicts of interest to declare.

Background In the last decades, evaluation of thrombotic complications secondary to acute leukemia (AL) has been poorly investigated. Only scant data are available on management and prevention of thrombosis in this setting. We performed a multicenter retrospective study with the aim to evaluate the management of venous thromboembolism (VTE) in patients with AL and to report the most commonly adopted regimens of treatment. Materials and methods Available clinical records of out and in-patients diagnosed with AL from January 2008 to June 2013 in 7 Reference Regional Hospitals were analyzed. Cases of VTE, including thrombosis in atypical sites [Retinal occlusion (RO) and Cerebral Sinus Thrombosis (SCT)], were reported. All data were recorded in a dedicated electronic database. The patient’s basic demographic data (age, gender, race), medical history, disease-related information, and laboratory data were extracted. Instrumental diagnosis of deep vein thrombosis (DVT), pulmonary embolism (PE) and RO and SCT was performed according to ACCP guidelines. Data were collected and analysed by the IBM SPSS Software 21.0 version (SPSS, Inc., Chicago, Ill, US) and the Epi Info software, version 3.2.2, (Centers for Disease Control and Prevention). Statistical analysis of quantitative and qualitative data, included descriptive statistics, was performed for all the items. Results Over a population of 1461 patients with AL, 99 (6.8%) cases of VTE were recorded, mainly in hospitalized patients: 72 cases were associated with Acute Myeloid Leukemia (AML) and 27 with Acute Lymphoblastic Leukemia (ALL), with a mean age of 52.2 ± 15.4 years (median age: 53years). In particular the incidence/ratio over the sub-population of AML-patients was 6.0%, that is 72/1191 cases; with a mean age of 54.7 ± 14.3 years (median age: 57 years). VTE occurred during chemotherapy (CHT) in 90/99 (90%) cases, mainly during the induction phase of treatment (in 70% of cases ),the remaining 9 cases were diagnosed in concomitance with acute leukemia. In both subgroups with VT, there was no statistical significant difference between time at diagnosis of VT and time at diagnosis of AL. Treatment of VTE was mainly based on Low Molecular Weight Heparin (LMWH), in accordance with results from previous studies and current guidelines (full dosage for the first month from diagnosis and reduced dosage at 75% for the following months). Thrombocytopenia occurred in 55 patients at diagnosis of AL, in 33 cases platelets were Conclusion VTE can complicate the clinical course of AL in a not negligible percentage of cases. Anticoagulant treatment schedules and duration in patients with AL are influenced by many factors, mainly related to chemotherapy and severe thrombocytopenia. In the analyzed subset of patients, full dose treatment with LMWH for at least one month followed by a dose reduction for at least three months was appropriate. Disclosures No relevant conflicts of interest to declare.

The front-line therapy for CLL young and fit patients is chemo-immunotherapy with Fludarabine-Cyclophosphamide and Rituximab (FCR). However, around three quarter of the patients with a newly diagnosed CLL are 65 years or older, with approximately 42% being older than 75 years and with age-related comorbidities. FCR regimen results in a significant myelosuppression and high rates of early and late infections. Hence, other less toxic regimens are under evaluation. Recently the German CLL study group reported an interim analysis of the CLL10 trial, who compared FCR vs Bendamustine-Rituximab (BR). The response rates to the 1st-line treatment with BR or FCR were comparable, and BR could be an alternative 1st-line treatment for medically fit pts. Notably, this study showed that pts treated with BR were often older (median 71 vs. 65 yrs; p 7). All patients had an ECOG performance status ranging from 0 to 2. Twenty-nine of 70 patients had Binet stage C, 12 patients were Binet A, 29 Binet B. Thirty-nine patients showed karyotype abnormalities at FISH analysis (data available in 54/70 patients). High risk FISH karyotype according to Dohner´s hierarchical model was detected in 17 patients (14 with del 11q, 3 with del 17p). Ten of them had del(13q14), 12 had trisomy 12 and 15 had normal karyotype. The analysis of the IGHV status, available in 50 patients, showed 25 patients with somatic mutation and 25 patients with germ-line sequences. Zap-70 data were available for 37/70 pts, 19 of them (51.3%) were Zap-70 positive. CD38 was available for 52 patients: it was positive in 27/52 pts (51.9%). (Table 1) A mean number of 5.46 courses of BR were given and the Bendamustine dose was reduced by more than 10% in 39 patients (55,7%). The main reason for dose reduction was haematological toxicities. The ORR rate was 88,6%,with 22 patients (31.4%) obtaining a CR and 40 patients (57,2%) obtaining a PR. Progression Free Survival, Time To Retreatment and Overall Survival rates at 2-years were 79%, 90.3% and 89.6%, respectively. Only the presence of del17 resulted to affect the response rate (p= 0.023) and PFS (p7 | 8/70 pts (11.4%) | | PB lymphocytes | 33.203/mmc | | Binet stage A | 12/70 pts (17.2%) | | Binet stage B | 29/70 pts (41.4%) | | Binet stage C | 29/70 pts (41.4%) | | ZAP70>20% | 19/37 pts (51.3 %) | | CD38> 30% | 27/52 pts (51.9%) | | Beta2microglobulin increased | 51/59 pts (86.4%) | | IgVH homology < 98% | 25/50 pts (50%) | | Normal FISH | 15/54 pts (27.8%) | | del 13q | 10/54 pts (18.5%) | | +12 | 12/54 pts (22.2%) | | del 11q | 14/54 pts (25.9%) | | del 17p | 3/54 pts (5.6%) | | Bulky syndrome | 16/70 pts (22.9%) | Table 1: Patients’ clinical-biological characteristics. PB, peripheral blood; IgVH, immunoglobulin heavy chain variable genes; FISH, Fluorescent In Situ Hybridization. Disclosures No relevant conflicts of interest to declare.

Crystallization following thermal annealing of thin film stacks consisting of alternating nm-thick titania/silica layers was investigated. Several prototypes were designed, featuring a different number of titania/silica layer pairs, and different thicknesses (in the range from 4 to 40 nm, for the titania layers), but the same nominal refractive index (2.09) and optical thickness (a quarter of wavelength at 1064 nm). The prototypes were deposited by ion beam sputtering on silicon substrates. All prototypes were found to be amorphous as-deposited. Thermal annealing in air at progressive temperatures was subsequently performed. It was found that the titania layers eventually crystallized forming the anatase phase, while the silica layers remained always amorphous. However, progressively thinner layers exhibited progressively higher threshold temperatures for crystallization onset. Accordingly it can be expected that composites with thinner layers will be able to sustain higher annealing temperatures without crystallizing, and likely yielding better optical and mechanical properties for advanced coatings application. These results open the way to the use of materials like titania and hafnia, that crystallize easily under thermal anneal, but ARE otherwise promising candidate materials for HR coatings necessary for cryogenic 3rd generation laser interferometric gravitational wave detectors.

A processing error in the signal template used in this search led to upper limits about 30% lower than we now know is warranted by the early S5 data. We have re-analyzed that data and find new upper limits on the strain parameter h 0 of 4.9 × 10–25/3.9 × 10–25 for uniform/restricted prior assumptions concerning the Crab inclination and polarization angles. These results have now been superseded by upper limits of 2.6 × 10–25/2.0 × 10–25 based on the full S5 data and presented in Abbott et al. (2009). The multitemplate search was not affected by the error. This is an Erratum for the article in Astrophysical Journal, 683 L45 2008

B-cell chronic lymphocytic leukemia (B-CLL) is an indolent lymphoproliferative disorder with a progressive accumulation of small, morphologically mature B lymphocytes in the bone marrow, blood and lymphoid tissues. Alemtuzumab (MabCampath) is a IgG1 monoclonal antibody (mAb) that target the CD52 antigen, a glycosylated peptide highly expressed on B-CLL cells. This mAb is active in patients with B-CLL refractory to alkylating agents and purine nucleoside analogues. The primary adverse event so far reported is the induction of a profound and prolonged depletion of CD4 and CD8 subpopulations leading to an immunodeficient status and the development of opportunistic infections [1,2]. Recently, Epstein-Barr virus (EBV) related lymphoma have been reported in patients with T and B cell lymphoproliferative disorder after treatment with alemtuzumab [2–5]. Here, we report a case of an EBV related lymphoproliferative disorder secondary to alemtuzumab therapy for B-CLL. A 53 years old man diagnosed in January 1999 as having stage Rai II classical B-CLL, was admitted to our department in June 2007 as a consequence of disease progression. Analysis of IgVH mutational status was not performed. However, peripheral blood flow cytometry analysis revealed that tumor cells expressed ZAP-70, but were negative for CD38 expression. He was previously treated with two cycles of fludarabine 25 mg/m with no response. In March 2001, he received six doses of rituximab 375 mg/m obtaining a partial remission. In December 2005, because of disease progression associated with Coombs positive autoimmune hemolytic anemia (AHA) he was treated with rituximabþfludarabineþ cyclophosphamide (FCR) for six cycles obtaining a partial remission with resolution of the (AHA). From June 2007 to July 2007, he received 12 doses of alemtuzumab 30 mg/m, obtaining the clearance of bone marrow neoplastic cells with persistence of lymph nodes involvement. CD4 and CD8 levels prior alemtuzumab therapy were 517/mL and 1380/mL, respectively. After 4 weeks of anti CD52 therapy, treatment was interrupted because of CMV reactivation which was successfully treated with ganciclovir. In October 2007, the patient presented with fever AHA recrudescence and hepatomegaly. Laboratory analysis showed high LDH level (1299 UI/L), hypoalbuminemia (2.5 g/dL), elevated liver enzyme (ALT: 92 UI/L; AST: 87 UI/L) and anemia (Hb 8.4 g/dL). Lymphocyte count on peripheral blood was less than 40/mL. A CT scan revealed the presence of multiple enlarged lymph nodes at both sides of the diaphragm and liver enlargement. An abdominal ecography revealed multiple hypoechogenic liver lesions which were biopsied and showed large B cells CD20þ. In situ hybridisation for EBV-RNA was strongly positive and serum EBV DNA viral load showed more than 6500 copies/mL. Bone marrow evaluation didn’t show any infiltration by neoplastic cells. The diagnosis of stage IV CD20þ

Although the therapy of acute myeloid leukemia (AML) has remarkably improved over the last 2-3 decades, two thirds of young adults still die of their disease. In elderly adults, who represent the majority of patients with AML, the results are even more unsatisfactory with less than 10% of patients being long-term survivors. Based on this, age is universally recognized as a critical prognosticator affecting outcome and therefore treatment choice. In consecutive series of adult patients with de novo AML, we have repeatedly demonstrated the prognostic role of minimal residual disease (MRD) as detected by flow cytometry. In particular, we have found that a level of MRD ≥ 3.5x10e-4 residual leukemic cells (RLC) at the end of consolidation is associated with a relapse rate of 70-80%. In the present study we evaluated whether the prognostic impact of MRD assessment after consolidation remained unaltered even in age-stratified (< 60 and > 60 years) populations of adult patients with de novo AML. To this end, we analyzed 149 young (median age 46, range 18-60) and 61 elderly adults (median age 67, range 61-78). All patients under study achieved complete remission after an induction therapy of the EORTC/GIMEMA protocols AML10, LAM99P and AML12 (for patients < 60 years) or AML13, AML15A and AML17 (for patients > 60 years). The two cohorts were well balanced in terms of frequency of FLT3-ITD and NPM1 mutated cases. A lower frequency of favorable-risk karyotypes was observed in elderly versus young patients (4% vs 19%, p=0.024). Of 149 younger patients, 105 (70%) underwent stem cell transplantation (SCT) (45 allogeneic, 60 autologous) as compared to 7 (11%) in the older age group (1 allogeneic, 6 autologous), (p= Disclosures: No relevant conflicts of interest to declare.

CLL is a heterogeneous disease with patients (pts) experiencing rapid disease progression and others living for years without requiring treatment. Recently, next generation sequencing has revealed new molecular alterations, targeting the NOTCH1 and BIRC3 genes which occur in about 10% CLL at diagnosis and correlate with poor outcome. Given the possibility of targeting NOTCH1 and BIRC3 with drugs currently under development, the primary endpoints of our research were: 1) to determine overall survival (OS) upon IGHV, NOTCH1, TP53 and BIRC3 in univariate analysis; 2) to correlate these genomic aberrations with other biological or clinical prognostic factors, and finally 3) to confirm NOTCH1, BIRC3 and TP53 as independent prognostic factors. We investigated 475 pts with a median age of 65 years (range 33-89), whose 160 had low Rai stage, 301 intermediate stage and 14 high stage. NOTCH1 mutations (mut) were studied by ARMS PCR for c.7544-7545delCT and by Sanger sequencing of NOTCH1 exon 34. Mutations of TP53 were analysed by DNA direct sequencing, while BIRC3 disruption (disr) was studied by Sanger sequencing for mutations and by interphase FISH for deletions. All these alterations were studied at diagnosis or before any chemotherapeutic approach. NOTCH1mut and TP53mut pts were 52 (10.9%) and 36/475 (7.6%), respectively. Thirty four patients were BIRC3mut (7.2%) and 26 BIRC3 deleted (5.5%) for a total of 46 cases (9.7%) BIRC3disr. NOTCH1, TP53 and BIRC3 alterations were mutually exclusive. There were significant correlations between NOTCH1 (P60 years (HR 3.8, P=0.00002), IGHV UM status (HR 0.30, P=0.0001), intermediate/high Rai stages (HR 2.8, P=0.0002), NOTCH1mut (HR 2.6, P=0.001), and BIRC3disr (HR 2.5, P=0.005) were confirmed to be independent adverse prognostic factors. Noteworthy, here, we demonstrated that genomic aberrations are able to improve the historical prognostic ability of the IgHV mutational status. In conclusion, genomic aberrations, particularly TP53mut, NOTCH1mut and BIRC3disr should be considered as novel important prognostic parameters in CLL and therefore they have to be necessarily considered in updated scoring prognostic systems. Disclosures: No relevant conflicts of interest to declare.

Abstract 1422 The outcome of young adult (< 60 years) with acute myeloid leukemia (AML) still remains unsatisfactory. In fact, in spite of complete remission (CR) rates ranging from 60 to 80%, only 30–40% of young patients will be long-term survivors. Advances in biologic characterization of AMLs are expected to enhance a more realistic assessment of disease aggressiveness so that therapies will be delivered in the context of a stratified approach. Cytogenetic/genetic profile is the most relevant prognostic factor established at diagnosis. Nevertheless, it is well recognized that it cannot always reliably predict outcome in individual patients. Minimal residual disease (MRD) detection promises to be an efficient tool to establish on an individual basis the leukemia's susceptibility to treatment and guide delivery of risk-tailored therapies. A further element underlying the dismal long-term outcome of young patients with AML pertains the chance to get access to allogeneic stem cell transplantation (ASCT) when carrying high-risk features. The extensive use of ASCT option is precluded by the paucity of full matched family donor (25–30%). These premises are the background to the risk-adapted approach, developed at the Institute of Hematology, University Tor Vergata, based on the following strategies: 1) combination of upfront cytogenetics/genetics and MRD status (< or ≥3.5×10−4 residual leukemic cells as counted by flow cytometry) at the end of consolidation to determine risk assignment; 2) once a given patients was categorized as high-risk (due to the expression of an unfavorable karyotype, FLT3-ITD positivity or post-consolidation positive MRD status) and therefore selected as candidate for ASCT, the transplant procedure was given whatever the source of stem cells. The present analysis includes 30 high-risk patients treated according to this design (prospective cohort = PC) and, for comparative purposes, 55 consecutive high-risk patients treated in an “old fashion” design based on donor availability (retrospective cohort = RC). The PC included 4 patients with favorable-karyotype (FK) and a MRD+ status, 12 with intermediate kayotype (IK) and a MRD+ status, 5 with unfavorable karyotype (UK) and 9 with FLT3-ITD mutation. The RC included 8 FK/MRD+, 34 IK/MRD+, 1 UK and 12 with FLT3-ITD mutation. In the PC, 22 (73%) of 30 patients received ASCT (8 matched family donor, 7 matched unrelated donor, 7 haploidentical related donor), 8 did not due to relapse (6) or because too early (2). In the RC, 12 (22%) received ASCT (11 matched family donor, 1 haploidentical related donor) whereas 24 (44%) autologous SCT (AuSCT); 19 were not transplanted at all due to relapse (13) or mobilization failure (6). Therefore, using the risk-adapted approach, 73% of high-risk patients in the PC received ASCT versus 22% of those in the RC (p Disclosures: No relevant conflicts of interest to declare.

Abstract 4581 Cytogenetic aberrations are considered major prognostic indicators for predicting the survival of chronic lymphocytic leukemia (CLL) patients (Dohner et al, 2000) and interphase fluorescent in situ hybridization (I-FISH) with specific probes is generally used to detect the most frequent abnormalities. Moreover, deletion 13q14.3 on FISH analysis which is the most common cytogenetic abnormality in CLL is a favorable prognostic biomarker when detected as a sole abnormality, even if a higher percentage of 13q- nuclei was found to be associated with significantly shorter time to treatment (P50% pts had received chemotherapy at the time of analysis, whereas only 27 (25%) of 110 of 13q- 50% (P=0.0003). In the context of del13q- subset, multivariate analysis of PFS confirmed the percentage of nuclei (P=0.00007) together with IgHV status (P=0.003) and ZAP-70 (P=0.0002) as an independent prognosticator. With regard to OS, percentage of nuclei (P=0.02) together with age (P=0.009) and IgHV status (P=0.03) was again confirmed as an independent variable. Therefore, the percentage of nuclei exhibiting 13q- at diagnosis has to be considered an important predictor of the clinical outcome and the clinical implications of an isolated 13q deletion in CLL appear more complex and important than originally considerated. Disclosures: No relevant conflicts of interest to declare.

Abstract 4236 Background: Acute myeloid leukemia (AML) involves infrequently the central nervous system (CNS). However, most studies examined paediatric patients. Thus little is known regarding CNS-involvement in adult AML. Therefore, we analyzed the data of patients with AML treated in SAL study group and Tor Vergata study group for CNS involvement. Methods: In this retrospective analysis in adult AML patients included in the prospective AML96- (NCT00180115), AML2003- (NCT00180102), AML60+ trials (NCT00180167) of the SAL study group and patients that were admitted to the University Hospital of Rome Tor Vergata from 2005 to 2011, 3863 patients were evaluated for CNS involvement of AML. The median age of the patients was 49 years (range, 18 –74 years). A total of 30 patients had CNS involvement at time of initial presentation and 30 patients had CNS involvement at first, second or third relapse. CNS involvement was proven depending on morphology and/ or flow cytometry of the Cerebrospinal fluid (CSF). Clinical variables of statistical significance were compared using the χ2-test for dichotomized variables and the Mann-Whitney U-test for continuous variables. The method of Kaplan Meier was used to estimate OS and event-free survival (EFS). Survival distributions were compared using the log-rank test. Results: 21 of 1862 patients (1%) in the AML96-trial, 26 patients of 1182 (2.2%) in the AML2003 trial, 3 of 486 patients (0.6%) in the AML60+ trial, and 10 of 270 patients (3.7%) in the University of Rome Tor Vergata studies had CNS involvement resulting to a total of 60 patients with a combined overall incidence of 1.6%. 30 patients had CNS involvement at the initial presentation and 30 patients at relapse of AML. The majority of patients (n=53, 88%) had de novo AML. Data from the Tor Vergata study group need further analysis therefore in this abstract patients from SAL study group were included. Extramedullary AML other than CNS involvement was observed in 21 patients (42 %) as compared to 246 (7%) in patients without CNS involvement, p < 0.001. Complex aberrant karyotype was not significantly higher in patients with CNS involvement as compared to those without, whereas patients with CNS involvement had a higher tendency for trisomy of chromosome 8 (n=8, 16%) in comparison with patients without CNS involvement (n= 277, 8%), p=0.03. AML FAB M5 occurred more frequently in patients with CNS involvement (n= 15, 30%) as compared to those without (n=459, 13%), p=0.01. Patients with CNS involvement at diagnosis had significantly higher lactate dehydrogenase (LDH) levels (1318 vs. 665 IE/l, p< 0.001) and higher white blood cell count (WBC) (64 vs. 35 Gpt/l, p Conclusion: CNS involvement in AML is a rare entity and it is accompanied with higher incidence of other extramedullary AML. This represents the largest analysis of AML patients with CNS involvement studied in the literature. Factors associated with an increased risk of CNS involvment include: trisomy of chromosome 8, FAB M5, higher LDH levels and higher WBC count at diagnosis. Patients with CNS disease at initial diagnosis of AML have similar survival outcomes as compared to those without CNS disease if treated by intrathecal therapy, whereas extramedullary relapse within the CNS is associated with poor outcome. Disclosures: No relevant conflicts of interest to declare.

Abstract 3887 Monoclonal B-cell lymphocytosis (MBL) is an asymptomatic monoclonal expansion of Disclosures: No relevant conflicts of interest to declare.

Abstract 4360 In spite of significant therapeutic improvements over the last 15–20 years approximately 20% of adult patients with acute myeloid leukemia (AML) is refractory and up to 60–70% relapses following front-line chemotherapy. Refractory/relapsed AML has a very unfavorable prognosis and novel agents are needed to improve outcome for these patients. Bortezomib is a potent inhibitor of the 26S proteasome which has been found to inhibit AML blast survival and interfere with the interaction between AML progenitors and microenviromental niche. The present study was designed to explore the safety and efficacy of Bortezomib given as single agent at the unconventional dose of 1.5 mg/m2, to patients with AML, unfit for conventional chemotherapy or with relapsed/refractory disease, after previous lines of therapy. Thirteen patients have been included in the study, being 10 evaluable. Nine males and 4 females, median age 70 (range 60–78), 4 and 1 cases were de novo and secondary AML, respectively. Six and 2 patients had refractory and relapsed disease, respectively. Bortezomib 1.5 mg/m2 was given on day 1,4,8 and 11 of each 21 day cycle, for a maximum of 8 cycles. Bone marrow samples were collected at baseline and, for response evaluation, on day 1 of each cycle. Three of 13 patients died early due to pulmonary infection. Among the remainder, we observed 5 haematological improvement (HI) defined as a reduction of peripheral blast count < 25% as compared to baseline and a Hb level increase by 2 gr/dL. One patient had a stable disease lasting for 3 months, the remaining 4 patients had a rapid progressive disease. Median number of delivered cycles until progression was 3 for patients with HI, whereas patients with progression were able to receive no more than 1 course of bortezomib. Median overall survival of patients with HI/stable disease was 4 months (range 3–8) versus 2 (range 1–2) of those with progression. Of 10 evaluable patients, 6 developed peripheral neuropathy which was NCI-CTC grade 4 in 2 (neurological bladder, requiring permanent catheterization in 1 instance) and grade 1–2 in 4. In the last, neuropathy resolved promptly after bortezomib discontinuation. In conclusion, bortezomib does have anti-leukemic activity and future clinical trials should focus on its combination with conventional chemotherapy. In this context, a dose reduction would be desirable due to neurologic complications observed in our study. Disclosures: Off Label Use: Bortezomib is a potent inhibitor of the 26S proteasome which has been found to inhibit AML blast survival and interfere with the interaction between AML progenitors and microenviromental niche.The purpose was to explore the safety and efficacy of Bortezomib given as single agent in refractory/relapsed AML patients.

Abstract 2692 Cytogenetic aberrations are considered major prognostic indicators for predicting the survival of chronic lymphocytic leukemia (CLL) patients (pts) [Dohner et al, 2000]. Given the difficulties in obtaining abnormal metaphases in CLL, fluorescent in situ hybridization (FISH) with specific probes is generally used to detect the most frequent abnormalities. Interphase FISH (I-FISH) is a rapid and sensitive technique for analysis of chromosome aberrations in CLL, but the limited number of DNA probes available to screen B-CLL results in a high number of cases presenting normal cytogenetics. Moreover, deletion 13q14 on FISH analysis which is the most common cytogenetic abnormality in CLL is a favourable prognostic biomarker when detected as a sole abnormality, but a higher percentage of 13q- nuclei was found to be associated with significantly shorter time to treatment (P Disclosures: No relevant conflicts of interest to declare.

Abstract 3574 Chronic lymphocytic leukemia (B-CLL) is a very heterogeneous disease with some patients experiencing rapid disease progression and others living for years without requiring treatment and therefore it is mandatory to find new prognostic markers. CD69 overexpression which resembles B cells at an earlier and greater state of activation (Damle, 2002 and 2007) and induces increased proliferation and survival of leukemic B-lymphocytes, may reflect an aggressive and progressive clinical outcome. The primary endpoints of our research were: 1) to determine progression free survival (PFS) and overall survival (OS) upon CD69 in univariate analysis; 2) to correlate CD69 with other clinical or biological prognostic factors such as age, Rai stages, lymphocyte doubling time, beta-2 microglobulin, CD38, CD49d, ZAP-70, cytogenetics by FISH and IgVH status and finally, 3) to confirm CD69 as an independent prognostic factor. We investigated 417 patients (pts), median age 66 years (range 33–89), 239 males and 178 females. With regard to modified Rai stages, 127 pts had a low stage, 272 an intermediate stage and 18 a high stage. CD69 was determined by multicolor flow cytometry, fixing the cut-off value at 30%. CD69+ pts were 111/417 (26.6%). CD69 12 months (260/337; P=0.0006), beta-2 microglobulin or Disclosures: No relevant conflicts of interest to declare.

Abstract 2359 Poster Board II-336 B-cell chronic lymphocytic leukemia (B-CLL) exhibits features of activated and antigen-experienced B-lymphocytes and CD69 overexpression resembles B cells at an earlier and greater state of activation (Damle, 2002 and 2007). Moreover, the recent in vitro generation of anti-CD69 monoclonal antibodies able to inhibit either tumor growth or enhance NK cell function (Esplugues, 2005) prompt us to extensively evaluate CD69 antigen in our B-CLL cases. The primary endpoints of our research were: 1) to determine progression-free survival (PFS) and overall survival (OS) upon CD69; 2) to assess the additive prognostic value of CD69 and ZAP-70 and finally 3) to confirm CD69 as an independent prognostic factor. We investigated 401 patients (pts), median age 65 years, 219 males and 182 females. With regard to modified Rai stages, 120 pts had a low stage, 263 an intermediate stage and 18 a high stage. ZAP-70 and CD69 were determined by multicolor flow cytometry, fixing the cut-off values > 20% and >30%, respectively. ZAP-70+ and CD69+ pts were 166/401 (41%) and 108/401 (27%), respectively. CD69 lower than 30% was significantly associated with low Rai stage (105/120; P12 months (258/332; P=0.00001), beta-2 microglobulin (B-2M) or < 60 years resulted to be the most significant prognostic factor (P=0.004) followed by CD38 (P=0.01), IgVH status (P=0.02) and ZAP-70 (P=0.04). In conclusion, CD69 antigen, determined by flow cytometry, should be considered a novel important prognostic parameter in B-CLL and its easy and rapid laboratory determination may allow us to identify early progressive pts in order to take timely therapeutic decisions. Disclosures: No relevant conflicts of interest to declare.

Abstract 1584 Poster Board I-610 The clinical advantage of using high-dose cytarabine (HDARAc) in induction chemotherapy for acute myeloid leukemia (AML) is still controversial. The purpose of our study was to explore the impact on the “quality of response” of an induction regimen containing standard dose (SD) ARAc versus HDARAc, by measuring minimal residual disease (MRD) once CR was achieved. MRD was determined by multiparametric flow cytometry on bone marrow samples collected at the end of induction and consolidation therapy. The threshold for MRD negativity was set below the number of 3.5×10-4 residual leukemic cells. We evaluated 111 patients with de novo AML, enrolled sequentially in DCE arm of AML10 (n=40) and in AML12 (n=71) EORTC/GIMEMA randomized trials between 1995 and 2007. In DCE arm of AML10, induction treatment combined ARAc (100 mg/m2 day 1-10), etoposide (50 mg/m2 day 1-5), and on days 1,3,5, daunorubicin (50 mg/m2). In AML12 trial, patients received the same treatment of DCE arm except for ARAc dose that was 100 mg/m2 day 1-10 or 3000 mg/m2/q12 hrs on days 1,3,5, and 7 according to randomization. As consolidation, all patients received ARAc (500 mg/m2/q12 hrs day 1-6) and daunorubicin (50 mg/m2, day 4-6). Median age was 45 yrs (range 18-60), 65 males and 46 females. Seventy-five patients were treated on SDARAc regimen and 36 on HDARAc regimen. The two groups were well balanced in terms of FAB classes, WBC count, cytogenetics, Pgp-170 expression, FLT3 and NPM1 mutation and post-remission transplant procedure (autologous or allogeneic) delivered. After induction, we observed a significantly higher frequency of MRD negativity in SDARAc arm vs HDARAc arm (82.% vs 18%, p=0.02). After consolidation, this figure was confirmed (84% vs 16%, p=0.01). At this stage, 3 further patients treated on the SDARAc arm, became MRD negative, whereas none in the HDARAc arm did so. Overall, median level of MRD was significantly lower in SDARAc group both after induction (1.1×10-2 vs 5.4×10-2, p=0.015) and consolidation (9×10-3 vs 3×10-2, p=0.02). Based on the combination of MRD status after consolidation and ARA-C schedule delivered, we identified 4 different groups of patients. Five years OS for SDARAc-MRDneg, HDARAc-MRDneg, SDARAc-MRDpos and HDARAc-MRDpos was 67%, 33%, 21% and 24%, respectively (p Disclosures No relevant conflicts of interest to declare.

Two locally optimum interferometer-network statistics for detecting unmodeled gravitational wave bursts in a non-Gaussian impulsive (glitchy) noise background are introduced. These follow from two possible approaches, where the sought transient signals are alternatively assumed as (i) unknown but deterministic or (ii) random. The first approach yields a locally optimum generalized likelihood ratio test detector, based on the maximum likelihood estimate of the gravitational wave signal. The second makes only minimal (least informative) assumptions about the sought signals, and yields a special version of Kassam's generalized-cross-correlation test detector. Both outperform the standard coherent network detector based on the Gaussian noise assumption. In the realistic case where the glitch noise distribution is non-stationary in time, or incompletely characterized, robust versions of these locally optimum network detectors can be effectively used.

Locally optimum network detectors of weak unmodelled gravitational wave bursts in non-Gaussian noise are introduced. Robust implementations coping with non-stationarities and/or uncertainties in the impulsive (glitch) noise component are discussed. Their performance is evaluated, capitalizing on a simple model for the glitch-noise component, with specific reference to a three-detectors (LIGO–Virgo) observatory.

Implementation of transplant procedures and the availability of alternative sources of stem cells for patients without HLA identical siblings has made allogeneic stem cell transplant (ASCT) a suitable therapy for many patient affected by acute myeloid leukemia (AML); consequently, in AML patients transplant strategies must be carefully designed according to stringent risk/benefit analysis. To date, risk assessment relies on identification of baseline prognostic parameters such as karyotype, which has become critical in order to choose post-remissional therapy. Furthermore, there are strong evidences that the presence of specific gene abnormalities, such as mutations of FLT3, NPM and c-kit, allow to identify, within homogeneous cytogenetic groups, subsets of patients with distinct clinical outcome. We hypothesized that, in order to guide the post-remission decisional process, more robust informations may derive from the combined evaluation of conventional baseline and delayed prognosticators. Minimal residual disease (MRD) detection is potentially the most efficient tool to investigate the quality of remission and might represent the ideal parameter to be associated with baseline biological features for prognostic purposes. Therefore, we aimed to determine whether combined analysis of karyotype and MRD, using multiparametric flow-cytometry (MPFC), could help to refine risk assessment in adult patients with AML, allowing the most appropriate post-remissional strategy to be selected. We analyzed 132 patients with AML who had intensive chemotherapy with EORTC/GIMEMA protocols. According to MRC classification, 22 (17%), 104 (78%) and 6 (5%), respectively, had good, intermediate and poor risk karyotype. Thirteen of 107 (12%) carried a FLT3-ITD. Within good and intermediate risk categories, MRD positivity (≥ 3.5×10−4 residual leukemic cells at the post-consolidation time-point) was associated with a worse prognosis in terms relapse free (RFS) and overall survival (OS). In fact, we observed that: MRD negative good and intermediate risk categories shared the same favorable prognoses with RFS and OS of 80% vs. 69% and 84% vs 54%, respectively; MRD positive good and intermediate risk categories fared as worse as those with poorrisk karyotype or FLT3-ITD in terms of RFS (28% vs. 17% vs. 0%) and OS (42% vs. 21% vs. 17%). Using this approach the conventional cytogenetic classification that uses three categories is simplified into 2 prognostically defined groups: favorable, including MRD negative good and intermediate risk karyotype; unfavorable, including MRD positive good and intermediate risk karyotype, poor risk karyotype and FLT3-ITD positive cases (Fig. 1). Based on these observations, we believe that ASCT is recommended, not only for poor-risk karyotype or FLT3 positive AML, but also for good/intermediate risk categories not gaining MRD negativity, being this option able to provide a superior chance of prolonged RFS (Maurillo et al, JCO 2008). On the other hand, patients belonging to MRD negative good/intermediate risk categories, who can experience a 5-years survival higher than 60%, may have their life expectancy hampered by the choice of a therapeutic strategy with a disadvantageous risk/benefit ratio: for this category a standard intensification procedure (chemo and/or autologous transplant) is indicated. In conclusion, the combined assessment of baseline prognosticators (cytogenetics) and parameters inherent the quality of response (MRD), is useful to define discrete categories of risk within the respective karyotypic groups, allowing tailored therapeutic approaches to be applied according to the actual clinical risk and avoiding under or over treatments. Figure 1 Figure 1.

The unbalance between anti-apoptotic (bcl-2) and pro-apoptotic mitochondrial proteins (bax) represents a critical mechanism explaining the high rate of resistance and treatment failure in acute myeloid leukemia (AML) (Del Poeta, 2003). Moreover, the availability of novel and effective pro-apoptotic compounds such as bortezomib (Attar, 2008) and gemtuzumab (Del Poeta, 2008) moved us to widely investigate the impact of mitochondrial proteins such as bcl-2, bax and 7A6 on AML prognosis. 7A6 antigen has been found to be exposed on the mitochondrial membrane during the early stages of apoptosis and is recognized by monoclonal antibody APO2.7. For this purpose, a large series of 420 non M3 AML patients (pts), median age 63 years, treated with intensive chemotherapy regimens, were tested. The aims of our research were: to correlate bax/bcl-2 and APO2.7/bcl-2 ratios, as measures of mitochondrial apoptosis, with other well-known prognostic factors such as age, cytogenetics, FLT3-ITD, P-glycoprotein; to evaluate whether mitochondrial apoptosis was able to dissect normal karyotype AML with regard to prognosis, and finally to confirm that mitochondrial apoptosis is an independent prognostic factor. Bcl-2, bax and 7A6 proteins were assessed by multicolor flow cytometry and bax/bcl-2 or APO2.7/bcl-2 ratios were obtained by dividing mean fluorescence intensity (MFI) of bax/MFI bcl-2 or MFI of APO2.7/MFI bcl-2. The thresholds of positivity were set at the median values >0.35 and >0.60, respectively. Fifty-nine percent of pts were bax/bcl-2 positive and 50% were APO2.7/bcl-2 positive. There were strict correlations between higher bax/bcl-2 or higher APO2.7/bcl-2 and FAB M2 or M4/M5 AML subgroups (p0.35 or APO2.7/bcl-2>0.60 and CD34 negativity (p

An analytic model a la Middleton of the impulsive noise component in the data of interferometric gravitational wave detectors is proposed, based on an atomic representation of glitches. A fully analytic characterization of the coherent network data analysis algorithm proposed by Rakhmanov and Klimenko is obtained, for the simplest relevant case of triggered detection of unmodeled gravitational wave bursts, using the above noise model. The detector's performance is evaluated under a suitable central-limit hypothesis, and the effects of both the noisiness of the pseudo-templates, and the presence of the impulsive noise component are highlighted.

In a remarkable proportion of adult AML patients (40–50%), no clonal abnormalities are found on standard cytogenetic analysis. In this group of patients, several gene mutations have been described, allowing to discriminate subgroups with distinct clinical outcome. Among these molecular signatures, FLT3, a receptor tyrosine kinase with important roles in hematopoietic stem/progenitor cell survival and proliferation, has been demonstrated to be mutated in about 1/3 of AML cases, identifying a subgroup of patients characterized by disappointing overall cure rates. Therefore, roughly 60% of patients with normal karyotype are not classifiable by this specific mutation. The purpose of the present study was to investigate, in this group of patients with no specific molecular signature the prognostic role of MRD as determined by multiparametric flow-cytometry (MPFC). We analyzed a group of 127 AML cases entered into the EORTC/GIMEMA protocols AML10/AML12 (age 61 yrs). By applying the maximally selected log-rank statistics, the threshold discriminating MRD negative from positive cases was set at 3.5 x10−4 residual leukemic cells, a level that selected, at the post-consolidation time-point, two groups of patients with distinct prognosis. Seventy-two out of 127 (56%) had a normal karyotype. Among these 72, 53 were studied for FLT3 mutational status; in 13 (25%) a mutated variant of FLT3 was detected. Among the remaining 40 patients with normal karyotype and unmutated FLT3, 39 were evaluable for the MRD status at the post-consolidation time-point: 9 patients were MRD− and 30 MRD+. These two subsets showed a distinct outcome in terms of 5-years RFS (83 vs. 23%, p=0.031). Interestingly, the FLT3−MRD+ patients shared with those FLT3 positive a similar poor prognosis (Figure 1). In recent reports, the evaluation of outcome depending on FLT3 status has been integrated with the analysis of the mutated status of other genes: FLT3-mutated cases associated frequently with Nucleophosmin (NPM1) exon-12 gene mutations but rarely with other mutations. The favorable impact of NPM1 mutations on OS and EFS clearly emerged in the group of normal-karyotype AML without FLT3 mutations. In a subset of 44 patients of our series either the mutations were investigated; this combined analysis identified 8 out of 44 (18%) patients FLT3 unmutated/NPM1 mutated with a better outcome (5-years OS 50% and RFS 50%, respectively) as compared to FLT3 unmutated/NPM1 unmutated and FLT3 mutated patients, which was however poorer than that of FLT3 unmutated/MRD− cases (Figure 1). In conclusion, MRD determination at the post-consolidation phase may help at improving the prognostic assessment of AML patients lacking specific chromosomal and/or molecular lesions, allowing risk-adapted post remissional therapies to be designed with more accurate modalities. Figure Figure

Nucleophosmin gene mutations (NPM1-Mt) are the hallmark of a large adult acute myeloid leukemia (AML) subgroup with normal karyotype and interact with p53 and its regulatory molecules (Arf, Hdm2/Mdm2), thus lowering cell proliferation and increasing apoptosis (Falini, 2007). Moreover, AML pts show co-existing NPM1-Mt and internal tandem duplications of FLT3 (FLT3-ITD) which increase potential for cell proliferation. Furthermore, genes and proteins involved in apoptosis, such as bcl-2 and bax, have been demonstrated to be relevant in response to treatment and outcome (Del Poeta, 2003). Therefore, we analysed NPM1-Mt, FLT3-ITD and apoptosis proteins (bcl-2 and bax) in 222 pts, affected by de novo non-M3 AML, median age 60 years, treated with intensive chemotherapy regimens according to GIMEMA-EORTC protocols. The aims of our study were: to correlate NPM1-Mt or FLT3-ITD with bax/bcl-2 ratio levels, as a measure of spontaneous apoptosis; to assess the independent prognostic significance of NPM1-Mt and FLT3-ITD. Bcl-2 and bax proteins were determined by multicolor flow cytometry and bax/bcl-2 ratio was obtained by dividing mean fluorescence intensity (MFI) of bax/MFI bcl-2. The threshold of positivity was set at the median value >0.35 (range 0.01–9.1). NPM1 mutations and FLT3-ITD were detected by multiplex PCR and capillary gel electrophoresis. One hundred-twenty-one/222 (54.5%) pts were bax/bcl-2 ratio positive, 54/222 (24.3%) were NPM1-Mt and 52/222 (23.4%) presented FLT3-ITD; 17/222 (7.6%) pts carried both FLT3-ITD and NPM1-Mt. There was a strong correlation between higher WBC counts (>100x109/L) and FLT3-ITD (P0.35) and NPM1-Mt without FLT3-ITD were significantly associated (30/37; P=0.0001), demonstrating that NPM1-Mt alone express high amount of spontaneous apoptosis. Moreover, NPM1-Mt cases were significantly related to FAB M4 or M5 AML (P=0.03). A normal karyotype was found in 37/45 (82%) NPM1-Mt pts (P=0.00001) and almost all NPM1-Mt cases were CD34 negative (47/54; P

Monoclonal antibodies in combination with chemotherapy allowed us to obtain more responses and longer response duration in B-cell chronic lymphocytic leukemia (B-CLL), reducing disease burden to levels detectable only by flow cytometry. Moreover, it has been reported that low-dose rituximab decreases CD20 antigen loss via shaving and promotes enhanced targeting in CLL (Williams, 2006). We performed a phase II study that added rituximab to fludarabine (Flu) as therapy for symptomatic, untreated CLL. Remission status was assessed by a multiparametric flow cytometric method based on the detection of CD19+CD5+CD79b– residual B-CLL lymphocytes. VH mutational status, CD38, ZAP-70 and cytogenetics were obtained in all pts before treatment. We defined as “high risk” pts having at least two of the following markers: unmutated IgVH, CD38>30%, ZAP-70>20%, intermediate/unfavorable cytogenetics (trisomy 12 or del11q or del17p). Eighty-two CLL pts, median age 61 years, received six monthly courses of Flu (25 mg/m2 for 5 days) and four weekly doses of rituximab (375 mg/m2) starting after completion of Flu therapy. According to modified Rai stages, 8 pts had a low stage, 70 an intermediate stage and 4 a high stage. Based on NCI criteria, 66/82 (80%) pts achieved a complete remission (CR), 12/82 (15%) a partial remission (PR) and 4/82 (5%) no response or progression. Hematologic toxicity included mainly neutropenia (grade 3 and/or 4 in 42 pts) and thrombocytopenia (grade 3 and/or 4 in 4 pts). Thirty-five pts in clinical CR or PR, either with CD5+CD19+CD79b– bone marrow (BM) cells >1% (MRD+, n=20 pts) or MRD negative but presenting CD5+CD19+ peripheral blood lymphocytes (PBL) >1000/microl (n=15 pts) within 1 year after completion of the induction treatment, underwent consolidation/maintenance therapy with four monthly cycles of rituximab at 375 mg/m2 followed by twelve monthly doses of rituximab at 150 mg/m2. The median follow-up duration was 46 months. Noteworthy, all B-CLL pts experienced a long progression-free survival (PFS) from the end of induction treatment (68% at 5 years). Nevertheless, CLL pts that underwent consolidation and maintenance therapy (n=35) showed a significant longer response duration (85% at 5 years, Figure). On the other hand, BM and PBL persistently MRD negative (>1 year) pts (n=29) showed a response duration similar to that of the consolidated pts (87% at 5 years). A significant shorter PFS was observed within CD38+ pts (39% vs 78% at 5 years, P=0.002), unmutated pts (45% vs 94% at 2.5 years, P=0.001) and ZAP-70+ pts (36% vs 88% at 6 years; P=0.00002). Notably, within the “high risk” subset (n=30), considering only MRD+ pts in CR or PR (n=20), MRD+ consolidated pts (n=11) showed a significant longer response duration (64% vs 13% at 2 years, P=0.006) in comparison with MRD+ unconsolidated pts (n=9). In conclusion, consolidation/maintenance therapy with rituximab prolongs significantly the response duration in B-CLL, improving also the outcome of the “high risk” subset. Figure Figure

CD69 membrane protein is expressed early in the activation of lymphoid cells and is inducible by B-cells through cross-linking of surface immunoglobulins. Moreover, B-CLL cells exhibit features of activated and of antigen-experienced B lymphocytes overexpressing activation markers such as CD23, CD25, CD69 and CD71 (Damle, 2002). Furthermore, we have demonstrated that ZAP-70+ CLL subgroup shows a rapid disease progression and an inferior overall survival (Del Principe, 2006). The generation of antimurine CD69 monoclonal antibodies able to induce down-modulation or partial depletion of CD69+ cells (Sancho, 2006), prompted us to evaluate the real impact of CD69 expression on B-CLL prognosis. The primary aims of our study were: to determine progression-free survival (PFS) and overall survival (OS) upon CD69 expression; whether CD69 could predict varied outcome within ZAP-70+ and ZAP-70 negative subgroups; and finally whether CD69 was an independent prognostic factor. Therefore, we investigated 247 pts, median age 65 years, 131 males and 116 females. With regard to modified Rai stages, 69 pts had a low stage, 167 an intermediate stage and 11 a high stage. CD69 was determined by multicolor flow cytometry fixing a cut-off value of 30%. CD69+ B-CLL pts were 73/247 (30%). CD69 >30% was significantly associated with an intermediate/high Rai stage (p=0.001), lymphocyte doubling time (LDT) 2.2 mg/dl (p=0.002). Lower CD69 expression and IgVH mutated status (>2%) were significantly correlated (73/92; p=0.0003). Furthermore, we found significant associations between lower CD69 and lower CD38 (137/184; p=0.02) or lower ZAP-70 (110/144; p=0.01). Lower levels of soluble CD23 (sCD23) were strongly associated with lower CD69 (127/158; p Figure Figure