2,232 research outputs found
Splenomegaly impacts prognosis in essential thrombocythemia and polycythemia vera: A single center study
Splenomegaly is one of the major clinical manifestations of primary myelofibrosis and is common also in other chronic Philadelphia-negative myeloproliferative neoplasms, causing symptoms and signs and affecting quality of life of patients diagnosed with these diseases. We aimed to study the impact that such alteration has on thrombotic risk and on the survival of patients with essential thrombocythemia and patients with Polycythemia Vera (PV). We studied the relationship between splenomegaly (and its grade), thrombosis and survival in 238 patients with et and 165 patients with PV followed at our center between January 1997 and May 2019
Extracellular vesicle microRNAs contribute to the osteogenic inhibition of mesenchymal stem cells in multiple myeloma
Osteolytic bone disease is the major complication associated with the progression of multiple myeloma (MM). Recently, extracellular vesicles (EVs) have emerged as mediators of MM-associated bone disease by inhibiting the osteogenic differentiation of human mesenchymal stem cells (hMSCs). Here, we investigated a correlation between the EV-mediated osteogenic inhibition and MM vesicle content, focusing on miRNAs. By the use of a MicroRNA Card, we identified a pool of miRNAs, highly expressed in EVs, from MM cell line (MM1.S EVs), expression of which was confirmed in EVs from bone marrow (BM) plasma of patients affected by smoldering myeloma (SMM) and MM. Notably,we found that miR-129-5p, which targets different osteoblast (OBs) differentiation markers, is enriched in MM-EVs compared to SMM-EVs, thus suggesting a selective packaging correlated with pathological grade. We found that miR-129-5p can be transported to hMSCs by MM-EVs and, by the use of miRNA mimics, we investigated its role in recipient cells. Our data demonstrated that the increase of miR-129-5p levels in hMSCs under osteoblastic differentiation stimuli inhibited the expression of the transcription factor Sp1, previously described as a positive modulator of osteoblastic differentiation, and of its target the Alkaline phosphatase (ALPL), thus identifying miR-129-5p among the players of vesicle-mediated bone disease
MESENCHYMAL STEM CELLS IN PH-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS: IDLE OBSERVERS OR PART OF THE DISEASE?
Residual vein thrombosis and D-dimer for optimizing duration of anticoagulation in idiopathic deep vein thrombosis.
Using pharmacokinetics for tailoring prophylaxis in people with hemophilia switching between clotting factor products: A scoping review
The objective of this scoping review is to summarize the current use of pharmacokinetics for tailoring prophylaxis in hemophilia patients switching between clotting factor products. Patients with hemophilia may require switching of clotting factor concentrates due to a variety of factors, but there have been perceived risks associated with switching, such as inhibitor development or suboptimal protection due to inadequate dosing while titrating treatment. Studies that look at patients switching from one clotting factor concentrate to another are categorized in terms of their primary and/or secondary objectives, notably biosimilarity and comparative pharmacokinetic studies and inhibitor development studies. Research on how best to switch concentrates with respect to dosing regimen are lacking, and currently a trial-and-error approach is used for dosing the new factor concentrate. In the future, studies looking at the predictability of pharmacokinetics (PK) of a new factor concentrate based on individual PK knowledge of the original factor concentrate may offer clinical benefit by providing a safer switching approach and protocol
BCR-ABL1 doubling-times and halving-times may predict CML response to tyrosine kinase inhibitors
In Chronic Myeloid Leukemia (CML), successful treatment requires accurate molecular monitoring to evaluate disease response and provide timely interventions for patients failing to achieve the desired outcomes. We wanted to determine whether measuring BCR-ABL1 mRNA doubling-times (DTs) could distinguish inconsequential rises in the oncogene’s expression from resistance to tyrosine kinase inhibitors (TKIs). Thus, we retrospectively examined BCR-ABL1 evolution in 305 chronic-phase CML patients receiving imatinib mesylate (IM) as a first line treatment. Patients were subdivided in two groups: those with a confirmed rise in BCR-ABL1 transcripts without MR3.0 loss and those failing IM. We found that the DTs of the former patients were significantly longer than those of patients developing IM resistance (57.80 vs. 41.45 days, p = 0.0114). Interestingly, the DT values of individuals failing second-generation (2G) TKIs after developing IM resistance were considerably shorter than those observed at the time of IM failure (27.20 vs. 41.45 days; p = 0.0035). We next wanted to establish if decreases in BCR-ABL1 transcripts would identify subjects likely to obtain deep molecular responses. We therefore analyzed the BCR-ABL1 halving-times (HTs) of a different cohort comprising 174 individuals receiving IM in first line and observed that, regardless of the time point selected for our analyses (6, 12, or 18 months), HTs were significantly shorter in subjects achieving superior molecular responses (p = 0.002 at 6 months; p < 0.001 at 12 months; p = 0.0099 at 18 months). Moreover, 50 patients receiving 2G TKIs as first line therapy and obtaining an MR3.0 (after 6 months; p = 0.003) or an MR4.0 (after 12 months; p = 0.019) displayed significantly shorter HTs than individuals lacking these molecular responses. Our findings suggest that BCR-ABL1 DTs and HTs are reliable tools to, respectively, identify subjects in MR3.0 that are failing their assigned TKI or to recognize patients likely to achieve deep molecular responses that should be considered for treatment discontinuation
Immunoistochemical expression of PD-1 and PD-L1 in bone marrow biopsies of patients with acute myeloid leukemia
Background. Haematological and non-haematological malignancies are able to escape the host immune by the capacity to hijack the immune check-points. Several immune check-point molecules are known, such as T cell immunoglobulin mucin-3 (TIM-3), cytotoxic T-cell antigen-4 (CTLA-4), programmed death-1 (PD-1) with its ligand PD-L1 and others.1 The function of these immune check-points is to prevent the damage resulting from an excessive activation of the immune response in the setting of chronic antigenic stimulation, thus leading to autoimmune phenomena, as proved in knock-out mice models. PD-1 is normally present on activated T lymphocytes membrane, acting as a negative costimulatory receptor. PD-L1 is constitutively expressed at low levels by resting lymphocytes, antigen presenting cells and certain immunologically privileged tissues like placenta and testis. PD-L1 expression can be induced as well. In an inflammatory/infective context when T cells recognize antigens expressed by MHC-complex they start to produce inflammatory cytokines. The resulting inflammation leads to the expression of PD-L1 by hematopoietic, epithelial and endothelial cells, activating PD-1 on the surface of T-cells and therefore blocking the immune response. Previous studies have found out that PD-1 is highly expressed on T-reg cells and their binding with PD-L1 enhances suppressor T-reg functions2,3; the activation of PD-1/PD-L1 pathway reduces the lytic capacity of NK cells and B cell antibody production. In solid neoplasms PD-L1 expression by cancer cells and persistent up-regulation of PD-1 by tumourinfiltrating lymphocytes is common45. All these findings brought to the development of check-point inhibitors in the contest of solid tumors and lymphoproliferative neoplasms such as lymphoma and myeloma where the immune checkpoint blockade treatment have shown efficacy in refractory/relapsed neoplasms6. Few investigations only have been conducted on the role of PD1/PD-L1 in myeloid neoplasms, such as acute myeloid leukemia, a haematological cancer characterised by high-risk of relapse and poor prognosis. In leukemia, the bone marrow serves as a sanctuary for neoplastic cells, these cells interact with the tumour microenvironment (TME), constituted by stromal cells, endothelial cells and immune cells. The marked activation of the PD-1/PD-L1 pathway contributes to the maintenance of an immunosuppressive microenvironment. In fact, blasts are able, through the production of immunoinhibitory factors, to suppress the function of immunosurveillance and immuno-elimination of the tumor by the effector T cells. The effector T cells are "exhausted" in their capacity to secrete granzyme B, perforine and interferon gamma, and there is an upregulation of the T-reg functions, in addition to the presence of myeloid-derived suppressor cells7. PD-L1 expression and his link with PD-1 on activated lymphocytes results in an impaired antitumoral activity in murine models8. Zhang et al. investigated the role of PD-1/PD-L1 engagement in murine AML showing that PD-1-/-mice generated augmented antitumoral response in comparison with wild type mice. Similar results were obtained using anti-PD-L1 antibodies.9 A study from Zhou et al. reported how the function of adoptively transferred AML-reactive CTLs was reduced by AML-associated Tregs and how Treg depletion followed by PD-1/PD-L1 blockade showed efficacy for AML eradication in murine models.10 Objective of the study. To assess the presence of PD-1 and PD-L1 positive cells, by immunohistochemistry, in bone marrow biopsies of patients with AML. Material and methods. Four micron thickness sections were obtained from the formalin-fixed paraffin-embedded specimens. Haematoxylin-eosin staining was performed to assess the morphologic features of bone marrow. Immunohistochemical stainings were performed using a Ventana Benchmark Ultra automated staining instrument according to the manufacturer’s recommendations, using anti-PD-1 (clone NAT105, Ventana) and anti-PD-L1 (clone 22C3, Dako) antibodies. Results. We obtained 34 bone marrow trephine biopsies from newly diagnosed AML patients, 17 males and 17 females with a 67.3 mean age. We used 10 healthy bone marrow specimens as normal controls. None out of 10 control bone marrows resulted positive for either PD-1 or PD-L1 expressing cells as expected. Eleven out of 34 AML bone marrows (32,4%) showed at least 1% of PD-L1 positive cells (fig.2 b,d,f), while 6 AML bone marrow samples (17,6%) were positive for at least 1% of PD-1+ cells (fig. 1 b). Discussion. Despite the presence of relevant preclinical data regarding the role of immune check-points, few studies to evaluate the PD1/PDL1 axis have been conducted in myeloid neoplasm. Jia et al. performed flow cytometry analysis on PBMCs and BMMCs of 22 newly diagnosed AML patients and observed a significantly increased frequency of PD-1 expressing CD8 T cells in bone marrow compared to peripheral blood, suggesting a more exhausted status of these cells in relation to the suppressivePaper environment11. Dail et al. measured PD-L1 expression in 7 AML patients using immunohistochemistry and flow cytometry and found that PD-L1 was detectable (>2% cells) in all patients.12 Yang et al. assessed 45 bone marrow biopsies of MDS, CMML and AML patients and found that leukemic blasts of 9 patients (20%) were PD-L1+, while 3 (7%) were positive for PD-1. All 4 controls tested were negative for both PD-1 and PD-L1.13 Daver et al. measured PD-1 expression on bone marrow aspirates of 74 AML patients using flow cytometry. The results showed higher PD-1 expression compared to healthy controls (n=8).14Acceped To our this is the largest study evaluating by immunohistochemistry the expression of PD-1 and PDL1 in AML bone marrows and shows a significative positivity of the activation of the PD-1/PD-L1 pathway which gives a rationale to further studies regarding the charateristics of the cells involved in the PD-1/PD-L1 pathway and the immunosuppressive microenvironment. An implementation of the PD-1/PD-L1 pathway evaluation in clinical setting could have prognostic significance since the expression of PD-L1 by AML blasts has been associated with poor-risk and intermediate-risk AML15, furthermore immune checkpoint inhibitors have shown promising results in maintenance treatment of high-risk AML16, underlining not only a prognostic but also therapeutic value of the PD1/PD-L1 evaluation
Clinical implications of discordant early molecular responses in CML patients treated with imatinib
A reduction in BCR-ABL1/ABL1IS transcript levels to <10% after 3 months or <1% after 6 months of tyrosine kinase inhibitor therapy are associated with superior clinical outcomes in chronic myeloid leukemia (CML) patients. In this study, we investigated the reliability of multiple BCR-ABL1 thresholds in predicting treatment outcomes for 184 subjects diagnosed with CML and treated with standard-dose imatinib mesylate (IM). With a median follow-up of 61 months, patients with concordant BCR-ABL1/ABL1IS transcripts below the defined thresholds (10% at 3 months and 1% at 6 months) displayed significantly superior rates of event-free survival (86.1% vs. 26.6%) and deep molecular response (≥ MR4; 71.5% vs. 16.1%) compared to individuals with BCR-ABL1/ABL1IS levels above these defined thresholds. We then analyzed the outcomes of subjects displaying discordant molecular transcripts at 3-and 6-month time points. Among these patients, those with BCR-ABL1/ABL1IS values >10% at 3 months but <1% at 6 months fared significantly better than individuals with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (event-free survival 68.2% vs. 32.7%; p < 0.001). Likewise, subjects with BCR-ABL1/ABL1IS at 3 months >10% but <1% at 6 months showed a higher cumulative incidence of MR4 compared to patients with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (75% vs. 18.2%; p < 0.001). Finally, lower BCR-ABL1/GUSIS transcripts at diagnosis were associated with BCR-ABL1/ABL1IS values <1% at 6 months (p < 0.001). Our data suggest that when assessing early molecular responses to therapy, the 6-month BCR-ABL1/ABL1IS level displays a superior prognostic value compared to the 3-month measurement in patients with discordant oncogenic transcripts at these two pivotal time points
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Disclosure of Information to Potential Subjects on Research Recruitment Web Sites
We examined systematically how a sample of Web sites that recruit participants for research on particular diseases present studies to potential subjects, exploring the presence of information about research benefits, risks, procedures, and incentives, including monetary incentives. Such data can elucidate the degree to which federal guidance is being followed and may have potential implications for policy, suggesting areas that IRBs, policy-makers, and regulators may want to consider further regarding online recruiting of research participant
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