Thromboembolic events in patients with paroxysmal nocturnal hemoglobinuria (PNH): Real world data of a Greek nationwide multicenter retrospective study.

Thrombosis is the most common and a life-threatening complication in patients with Paroxysmal Nocturnal Hemoglobinuria. One-third of patients with PNH experience at least one thromboembolic event during the course of the disease, with thrombosis being the most common cause of death in these patients. The mechanism of thrombosis in PNH is complex and continues to be of great research interest. Since the introduction of C5 complement inhibitors in the treatment of PNH, the incidence of thromboembolic events has decreased substantially. We retrospectively analyzed data concerning the thrombotic episodes of 41 patients with PNH from 14 different national hematology centers in Greece. Sixteen patients (39%) experienced at least one episode of thrombosis, including, seven (43.8%) at diagnosis, seven (43.8%) during the course of the disease and two (12.5%) patients prior to PNH diagnosis. Nearly half of these individuals (n=7, 43.8%) had multiple episodes of thrombosis during the course of their disease. The most common sites of thrombosis were intra-abdominal veins. Three out of 26 patients developed thrombosis while on eculizumab. In none of the 16 patients, the thrombotic event was fatal. Our findings, despite the small number of patients, confirmed that thrombosis continues to be a significant complication of PNH affecting more than one third of the patients.

Lactobacillus paracasei K5 displays adhesion, anti-proliferative activity and apoptotic effects in human colon cancer cells.

Lactobacillus paracasei K5 is a lactic acid bacteria (LAB) strain, isolated recently from feta-type cheese. Its probiotic potential has been demonstrated in a series of established in vitro tests. Moreover, incorporation of L. paracasei K5 as starter culture offered organoleptic and technological advantages to novel fermented food products. In the present study, further investigation of the potential probiotic activity of L. paracasei K5 was performed and its mechanisms of action were investigated. Employing quantitative analysis and confocal, fluorescent microscopy the adhesion properties of the above strain were studied. L. paracasei K5 displayed efficient adherence capacity to Caco-2 colon cancer cells, similarly to the reference strains Lactobacillus casei ATCC 393 and Lactobacillus rhamnosus GG. Moreover, treatment of Caco-2 cells with L. paracasei K5 inhibited cell proliferation in a time-and dose-dependent manner. The anti-proliferative effects appear to be mediated through induction of apoptosis via modulation of expression of specific Bcl-2 family proteins. These results elucidate the mechanisms of action of L. paracasei K5 and enhance its potential probiotic activity.

Potentially probiotic Lactobacillus strains with anti-proliferative activity induce cytokine/chemokine production and neutrophil recruitment in mice.

Lactobacillus pentosus B281 and Lactobacillus plantarum B282 are two Lactobacillus strains previously isolated from fermented table olives. Both strains were found to possess probiotic properties and displayed desirable technological characteristics for application as starters in novel functional food production. In the present study the anti-proliferative and immunostimulatory activities of the two strains were investigated. Firstly, we demonstrated that live L. pentosus B281 and L. plantarum B282 significantly inhibited the growth of human colon cancer cells (Caco-2) in a time- and dose-dependent manner. By employing the air pouch system in mice, we showed that administration of both strains led to a rapid and statistically significant infiltration of leukocytes in the air pouch exudates. The phenotypical characterisation of the recruited immune cells was performed by flow cytometry analysis. We demonstrated that the majority of the infiltrated leukocytes were neutrophils. Finally by using the Mouse Cytokine Array Panel A Detection Antibody cocktail, we showed that both strains induced the expression of granulocyte-colony stimulating factor, interleukin (IL)-1α, IL-1ß, IL-6, chemokine (C-X-C motif) ligand (CXCL)-1, chemokine (C-C motif) ligand (CCL)-3, CCL-4, and CXCL-2 and diminished the expression levels of soluble intercellular adhesion molecule, macrophage colony-stimulating factor and metallopeptidase inhibitor 1. Our results showed that both strains display anti-proliferative and immunostimulatory properties equal or even better in some cases than those of established and commonly used probiotic strains. These findings further support the probiotic character of the two strains.

Poly (ADP-ribose) polymerase 1 mRNA levels strongly correlate with the prognosis of myelodysplastic syndromes.

Poly (ADP-ribose) polymerase 1 (PARP-1) has a central role in the repair of DNA breaks and is a promising treatment target in malignancy. We measured PARP1 mRNA levels by a SYBR-green-based PCR in the bone marrow of 74 patients with myelodysplastic syndrome (MDS) and correlated them to their demographic, hematologic and prognostic characteristics. The median PARP1 mRNA levels were correlated to the type of MDS (2008/2016 WHO classification, P=0.005) and to the IPSS score (P=0.002). A correlation was also found with the IPSS-R score (P=0.011) and the cytogenetic risk (P=0.008). In all cases, higher PARP1 levels were correlated with a higher risk category. Moreover, we found a significant survival disadvantage for patients with high PARP1 levels (median survival of 37.4 months versus 'not reached' for low PARP1 levels, P=0.0001, and a 5-year survival rate of 29.8 versus 88.9%, respectively). PARP1 mRNA levels were found to be the stronger predictor of survival in multivariate analysis. These correlations have never been reported in the past and may render PARP1 a prognostic factor to be incorporated in the current prognostic systems for MDS, also laying the basis for clinical trials evaluating PARP1 inhibitors in higher-risk MDS.

Successful response in a case of severe pustular psoriasis after interleukin-1ß inhibition.

Generalized pustular psoriasis (GPP) is a severe type of psoriasis accompanied by systemic and often life-threatening manifestations. The efficacy of the interleukin (IL)-1 antagonist anakinra in cases of GPP underscores the role of IL-1 in disease pathogenesis. We present a case of a middle-aged man who developed an abrupt and severe form of GPP with severe eosinophilia and cholestatic hepatitis. The patient received salvage treatment with a combination of glucocorticoids, hydroxyurea and imatinib, while administration of the IL-1 inhibitor anakinra resulted in remission of hepatitis and a significant skin improvement. However, due to persistent hypersensitivity skin reactions, anakinra was withdrawn and replaced with the anti-IL-1ß antagonist canakinumab. As a result of canakinumab, the patient's skin completely cleared, while no systemic manifestations recurred. After 1 year of continuous canakinumab therapy, the patient remained virtually free of symptoms, while the drug was well tolerated.

Proteolytic matrix metallopeptidases and inhibitors in BCR-ABL1-negative myeloproliferative neoplasms: correlation with JAK2 mutation status.

BACKGROUND/AIMS: Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) share the same acquired lesion JAK2(V617F) and may exhibit substantial overlap. Variability in JAK activation and allele burden, complemented by host, genetic and non-genetic modifiers, determine the phenotype. The aim of this study was to investigate the presence of the JAK2 mutation in association with the ratio of metallopeptidases inhibitors (TIMPs) to tissue metallopeptidases (MMPs) in MPNs, where inhibitory rather than proteolytic activity in marrow microenvironment appears to predominate. METHODS: 94 patients with polycythemia vera, essential thrombocythemia and primary myelofibrosis, and 102 healthy individuals were evaluated. Allele-specific PCR and RFLP were used to detect JAK2 and genomic status. Serum concentrations of MMP and TIMP were measured by ELISA. The parameters were assessed with covariance analysis, and adjusted for gender, age and co-morbidity. RESULTS: Mutation frequency was 81.91%. Abnormal TIMP/MMP ratios were identified in all three diseases. JAK2 mutation was correlated with significant changes in TIMP concentrations. CONCLUSIONS: Identification of an abnormal TIMP/MMP ratio in all three diseases, regardless of the JAK2 status, indicates invariable marrow remodeling. In this particular group of patients, presence of a JAK2(V617F) mutation, being associated with even higher ratios, appears to be a concurring participant in bone marrow-reforming processes. Additional research may delineate correlates with the JAK2 allelic burden.

Cardiovascular involvement in patients with beta-thalassemia major without cardiac iron overload.

BACKGROUND: Cardiovascular complications are common in beta-thalassemia major (beta-TM), mainly attributed to increased cardiac iron depositions. Early cardiovascular involvement in patients without cardiac symptoms and without cardiac iron overload has not been adequately investigated. METHODS: Twenty six patients (11 males) with beta-TM, on chelation therapy, age 23+/-4 years without cardiac iron overload (measured by magnetic resonance imaging), and 30 age and gender matched healthy controls were included in the study. Carotid-femoral and carotid-radial pulse wave velocity (PWVc-f and PWVc-r) and augmentation index (AI) were measured by SphygmoCor device; carotid intima-media thickness; left ventricular (LV) dimensions and function; left atrial (LA) volume and function were assessed by echocardiography. RESULTS: Patients with beta-TM had higher PWVc-f (8.4+/-1.4 vs 7.2+/-1.1 m/s, p=0.002) and augmentation index (21.7+/-10.9 vs 14.7+/-9.7%, p=0.04) indicating decreased aortic elastic properties; greater LV mass index (72.0+/-13.3 vs 63.8+/-11.5 g/m(2), p=0.04) and greater LA volumes. Multivariate logistic regression analysis revealed that higher PWVc-f was independently associated with higher LV mass [OR 1.74 95%CI (1.09-2.88), p=0.026]; and greater LA dimensions [OR 1.68 95%CI (1.04-2.72), p=0.035]. CONCLUSIONS: In the absence of cardiac iron overload, asymptomatic patients with beta-TM demonstrated aortic stiffening associated with increased LV mass and LA enlargement. These alterations may represent signs of early cardiovascular involvement.

Kinetics, function and bone marrow trafficking of CD4+CD25+FOXP3+ regulatory T cells in myelodysplastic syndromes (MDS).

CD4(+)CD25(+)FOXP3(+) T regulatory cells (T(regs)) prevent autoimmunity by restricting overexuberant immune responses, but the same subpopulation can incur detrimental effects on antitumor responses. In both cases, the suppressor potential of T(regs) appears to be strongly influenced by their compartmentalization. In myelodysplastic syndromes (MDS), immune deregulation and autoimmunity in the early stages might lead to ineffective hematopoiesis and bone marrow (BM) failure, whereas late-stage disease is characterized by the immune escape of the malignant clone. We show that these two stages of MDS are associated with differential T(reg) activity. Specifically, we found that in early stage MDS, compared with normal hematopoiesis and late stage MDS, T(regs) are dysfunctional and their BM homing through the CXCL12/CXCR4 axis is seriously impaired as a result of CXCR4 downregulation. Conversely, in late stage MDS, T(regs) are systemically and locally expanded and retain their function and migratory capacity. Moreover, T(reg) levels follow the disease course and are significantly reduced in treatment responding patients. Our findings indicate T(reg) involvement in the pathophysiology of MDS; defective suppressor function and BM trafficking of T(regs) may be important in the autoimmune process of early MDS, but increased T(reg) activity could favor leukemic clone progression in late stage disease.

Adding fresh frozen plasma to rituximab for the treatment of patients with refractory advanced CLL.

BACKGROUND: Many patients with chronic lymphocytic leukaemia (CLL) develop progressive, treatment-resistant disease. Rituximab (RTX), a monoclonal antibody targeting CD20 on B lymphocytes and widely used in other indolent B cell neoplasms is less efficacious in CLL, possibly due to associated complement deficiencies. OBJECTIVE: To examine in open trial whether providing complement by concurrent administration of fresh frozen plasma (FFP) will enhance the effect of RTX in CLL. SETTING: Outpatient haematology clinics in Israel and Greece. PATIENTS: Five patients with severe treatment-resistant CLL. All had been previously treated with fludarabine and three also failed treatment with RTX. INTERVENTION: Two units of FFP followed with RTX 375 mg/m(2) as a single agent, repeated every 1-2 weeks, as needed. RESULTS: A rapid and dramatic clinical and laboratory response was achieved in all patients. Lymphocyte counts dropped markedly followed by shrinkage of lymph nodes and spleen and improvement of the anaemia and thrombocytopenia. This could be maintained over 8 months (median) with additional cycles if necessary. Treatment was well tolerated in all cases. CONCLUSION: Adding FFP to RTX may provide a useful therapeutic option in patients with advanced CLL resistant to treatment.

Long-term bone marrow cultures (LTBMC) from essential thrombocythemia (ET) patients with or without JAK2617V>F mutation.

Approximately half of essential thrombocythemia (ET) patients and almost all with polycythemia vera (PV) bear the activating JAK2617V>F point mutation, which arises at the multipotent haemopoietic progenitor cell level. Although ET is mainly characterized by megacaryocyte proliferation, the cases that are positive for the JAK2617V>F mutation also show increased bone marrow cellularity and higher erythrocyte and granulocyte counts. After establishing short- and long-term bone marrow cultures we found that the frequency of committed haemopoietic progenitors in the bone marrow, was not increased in JAK2617V>F positive ET compared to the negative ones, whereas in long-term cultures (LTBMC) JAK2617V>F positive ET display a growth pattern more similar to that observed in LTBMC produced by PV marrow cells. Our data support the notion that JAK2617V>F positive ET and PV represents a continuum spectrum of alterations within the same disease.

Addition of cyclosporin-A to chemotherapy in secondary (post-MDS) AML in the elderly. A multicenter randomized trial of the Leukemia Working Group of the Hellenic Society of Hematology.

In elderly patients with secondary leukemia, poor therapeutic response and low overall survival have been attributed mainly to age and to the primary resistance of leukemic cells to chemotherapy. Modulation of resistance has been attempted in different studies, but the results have been contradictory. We conducted an open, randomized multicenter clinical trial involving patients more than 60 years old with secondary leukemia preceded by a myelodysplastic syndrome. The induction chemotherapy regimen included idarubicin, cytarabine, and etoposide (group A); randomization involved simultaneous administration of cyclosporin-A per os (group B). Fifty-five patients were evaluated, 26 in group A and 29 in group B. Overall complete remission was achieved in 40% of the patients, 27% vs 52% in groups A and B, respectively (p=0.01). Leukemia-free survival was more favorable in patients who received cyclosporin-A, 12 vs 7 months for groups B and A, respectively (p=0.03). In a follow up period of 30 months, 7 out of 55 patients (13%) were alive, 4 of whom were in complete remission. Five out of the 7 alive patients were randomized in group B and had received cyclosporin-A. Treatment failure was higher in group A [19 of 26 patients (73%)] than in group B with CsA [14 of 29 patients (48%)] (p<0.0001). Treatment-related toxicity/mortality was 13%. Modulation of drug resistance by CsA in elderly people suffering from secondary acute leukemia may improve the outcome of chemotherapy without increasing drug toxicity and treatment-related mortality.

Long-term remission of recalcitrant tumour-stage mycosis fungoides following chemotherapy with pegylated liposomal doxorubicin.

Advanced stage mycosis fungoides (MF) generally has a poor prognosis, and currently there is no standard treatment available. Here we report the case of a young woman with recalcitrant tumour-stage MF (T3, stage IIb) whose disease was unresponsive to several therapeutic modalities, but who has showed sustained clinical response to pegylated liposomal doxorubucin. No severe infectious complications have been observed. The use of this drug in tumour-stage MF should be investigated further.