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The treatment of diffuse large B cell lymphoma (DLBCL) is generally based on multidrug chemotherapy, for instance the therapy with rituximab together with cyclophosphamide, vincristine, doxorubicin, and prednisone (R-CHOP). A significant proportion of DLBCL patients benefit from rituximab-based chemoimmunotherapy. However, among patients with DLBCL toxic effects due to therapy treatment are still very frequent, as well as inter-individual differences in the outcomes of patients even having similar stage, histological grade and histopathological type of the tumor. The present paper reviews the actual status of pharmacogenomics studies concerning gene polymorphisms that may affect response and tolerability to R-CHOP therapeutic regimen used to treat DLBCL. There are clear evidences that polymorphisms of genes codifying for protein are involved in cytotoxicity induced by R-CHOP regimen. Moreover, polymorphisms in genes encoding TNF-superfamily cytokines and proteins involved in controlling cellular cycle and tumor growth may be related to variability in efficacy of R-CHOP therapy in DLBCL patients. This knowledge emphasizes the clinical meaning and importance of pharmacogenetics in oncology. The main merit of our study seems to have tried for the first time a comprehensive review of gene polymorphisms that are involved in the response to an entire therapeutic protocol, R-CHOP, in a specific disease, DLBCL, rather than examining polymorphisms referred to individual drugs among themselves not connected or used to treat different pathological conditions. Indeed, it seems clear that only the analysis of a constellation of polymorphisms can really be useful in clinical practice, while knowledge of a single polymorphism seems to give a limited contribution to our ability to use genetic analysis to the management of patients with malignant blood disorders. [ABSTRACT FROM AUTHOR]

Abstract: POEMS syndrome, is a rare condition characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal proteinaemia, and skin lesions. We report a rare case of a patient affected by Waldenström macroglobulinemia, who developed POEMS syndrome and who presented at the time of diagnosis with oral manifestations of the lymphoma and an osteonecrosis of the jaw (ONJ) after rituximab treatment. Although the etiology of ONJ is not known, it is likely that several factors are at play, including endothelial cell damage, decreased angiogenesis, and microvascular compromise. Our patient was treated with rituximab for a long period, and recent studies have demonstrated the possibility that rituximab, a monoclonal antibody directed against the CD20 can exert part of its anti-tumor action, through its action on angiogenesis. Although our report does not allow identification of rituximab as a new risk factor for the onset of the ONJ, further studies seem necessary to exclude a role of the antibody in the alterations of angiogenesis that could lead to the development of the syndrome after rituximab treatment. [Copyright &y& Elsevier]

Abstract: Objectives: Oxidative stress has a clear pro tumoral effect in myeloproliferative neoplasms (MPDs). In this study, we analyzed oxidative stress in patients with essential thrombocythemia (ET) and polycythemia vera (PV). Design and methods We analyzed serum levels of advanced oxidation protein products (AOPPs) degradation, advanced glycation end products (AGEs), and protein nitrosylation in ET and PV patients. We also evaluated neutrophil gelatinase-associated lipocalin (NGAL) levels, an acute phase protein isolated in human neutrophils, the activation status of platelets and leukocytes, and the JAK2 V617F mutation status. Results: AOPPs and s-nitrosylated proteins were significantly higher in PV and ET subjects as compared to healthy volunteers, while AGEs were higher in ET subjects with respect to controls. Moreover, in PV patients we found a correlation between s-nitrosylated proteins and Hb value. In ET patients AGEs were significantly higher in patients with thrombosis compared with those without thrombotic events. Conclusions: Our results suggest that oxidative stress could play a role in the physiopathology of MPDs and in the onset of myeloproliferative associated thrombotic risk. [Copyright &y& Elsevier]

Abstract: Objectives: To evaluate carbonyl groups (CG) serum levels in B-chronic lymphocytic leukemia (B-CLL) patients. Design and methods: CG serum levels were assessed in 48 B-CLL patients and in 30 control subjects. Results: CG were increased in B-CLL patients. We found a positive correlation between CG with CD38 expression and a negative correlation with ZAP 70 expression. Conclusions: B-CLL patients displayed an unbalance of the oxidative stress. CG serum levels could be considered as a prognostic factor in B-CLL. [Copyright &y& Elsevier]

A study analyzed the concentration of circulating endothelial progenitor cells during each trimester in 7 healthy pregnant women and compared levels with those in 7 pregnant women with gestational diabetes and 7 with hypertension without proteinuria. [ABSTRACT FROM AUTHOR]

• Multiple myeloma is presently an incurable malignancy. • Sirtuins are a family of (NAD)-dependent deacetylases. • Sirtuins are involved in cancer inhibition and tumorigenesis. • Sirtuins 2 and 3 are downregulated in multiple myeloma. • They are correlated with clinical stage and redox imbalance. Sirtuins comprise seven family elements (SIRT1-7) involved in various cell signalling pathways comprising cancer inhibition and tumorigenesis. The present study aims to evaluate SIRT2 and SIRT3 gene expression and potential redox reactions in patients with multiple myeloma (MM) at onset and its correlation with disease status, extent and presence of organ damage secondary to myeloma. Total RNA was extracted from 17 MM patients and 10 controls to assess gene expression using real-time PCR. The NAD+/NADH ratio as well as the levels of glutathione peroxidase (GPx) and hydrogen peroxide (HP) in peripheral blood mononuclear cells (PBMCs) were determined using established biochemical assays. SIRT2 and SIRT3 expression is reduced in MM patients compared to healthy controls. Correlational analysis demonstrated that SIRT2 reduction is associated with advanced clinical stage and with more advanced bone lesions than in the remaining patients. SIRT3 expression is correlated with lytic bone lesions. Biochemical analysis indicated an imbalance of oxidative stress biomarkers with low concentrations of the antioxidant enzyme GPx, low amounts of NAD + and higher concentrations of pro-oxidant enzyme HP in PBMCs of MM patients compared to controls. Moreover, MM patients with bone lesions had lower concentrations of NAD + and GPx in PBMCs than patients without signs of bone disease. In addition, MM patients had higher quantities of intracellular HP than controls. Our results demonstrate that SIRT2 and SIRT3 are downregulated in MM and that lower concentrations correlate with an advanced stage of disease and redox imbalance. We conclude that SIRT2 and SIRT3 together with oxidative stress biomarkers, may be useful for improved risk stratification of MM patients. [ABSTRACT FROM AUTHOR]

• Immune Checkpoints are parts of the immune system that identify cancer cells. • Multiple myeloma is characterized by an altered immune surveillance. • Immune Checkpoint Inhibitors activate T-cells, inducing apoptosis of cancer cells. • Immune Checkpoint Inhibitors have been developed to treat multiple myeloma. The human immune system has structures called checkpoints controlling the intensity and the duration of immune responses. In the last years, studies and research have been concentrating on creating new drugs recognized as Immune Checkpoint Inhibitors that have been launched in clinical practice to treat patients with several types of cancer, including multiple myeloma. Multiple myeloma is characterized by dysfunctions in humoral and cellular immunity altering immune surveillance and support tumor advancement to escape: in particular, the disease causes the inactivation of T-cells because of their bond with antigens shown in cancer cells. It can be stated that checkpoint inhibitors "inhibit the inhibition" of cell-mediated immunity and induce tumor cells apoptosis. In this review we have focused our attention on summarizing current information about Immune Checkpoint Inhibitors which have been developed in the last years to treat multiple myeloma; particular consideration will be dedicated to describing their mechanism of action and their potential use in therapy. Further investigations are necessary in this field to define the possibility of an effective and safe inclusion of these drugs in clinical practice. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a malignant B-cell neoplasm with accumulation of malignant plasma cells in bone marrow. Pharmacological therapy improves response frequency even if with various associated toxicities. Herein, we investigated if combination of curcumin with carfilzomib (CFZ) can induce a better cytotoxic effect on in vitro cultured U266 cells. Cell viability data showed that curcumin significantly ameliorates CFZ cytotoxic effect. Furthermore, curcumin alone did not affect proteasome at the tested dose, confirming the involvement of different mechanisms in the observed effects. U266 cells exposure to curcumin or CFZ increased reactive species (RS) levels, although their production did not appear further potentiated following drugs combination. Interestingly, NF-κB nuclear accumulation was reduced by treatment with CFZ or curcumin, and was more deeply decreased in cells treated with CFZ-curcumin combinations, very likely due to the different mechanisms through which they target NF-κB. Our results confirmed the induction of p53/p21 axis and G0/G1 cell cycle arrest in anticancer activities of both drugs, an effect more pronounced for the CFZ-curcumin tested combinations. Furthermore, curcumin addition enhanced CFZ proapoptotic effect. These findings evidence that curcumin can ameliorate CFZ efficacy, and lead us to hypothesize that this effect might be useful to optimize CFZ therapy in MM patients. [ABSTRACT FROM AUTHOR]

The ubiquitin-proteasome system (UPS) is the major non-lysosomal proteolytic system for the degradation of abnormal or damaged proteins no longer required. The proteasome is involved in degradation of numerous proteins which regulate the cell cycle, indicating a role in controlling cell proliferation and maintaining cell survival. Defects in the UPS can lead to anarchic cell proliferation and to tumor development. For these reasons UPS inhibition has become a significant new strategy for drug development in cancer treatment. In addition to the constitutive proteasome, which is expressed in all cells and tissues, higher organisms such as vertebrates possess two immune-type proteasomes, the thymoproteasome and the immunoproteasome. The thymoproteasome is specifically expressed by thymic cortical epithelial cells and has a role in positive selection of CD8 + T cells, whereas the immunoproteasome is predominantly expressed in monocytes and lymphocytes and is responsible for the generation of antigenic peptides for cell-mediated immunity. Recent studies demonstrated that the immunoproteasome has a preservative role during oxidative stress and is up-regulated in a number of pathological disorders including cancer, inflammatory and autoimmune diseases. As a consequence, immunoproteasome-selective inhibitors are currently the focus of anticancer drug design. At present, the commercially available proteasome inhibitors bortezomib and carfilzomib which have been validated in multiple myeloma and other model systems, appear to target both the constitutive and immunoproteasomes, indiscriminately. This lack of specificity may, in part, explain some of the side effects of these agents, such as peripheral neuropathy and gastrointestinal effects, which may be due to targeting of the constitutive proteasome in these tissues. In contrast, by selectively inhibiting the immunoproteasome, it may be possible to maintain the antimyeloma and antilymphoma efficacy while reducing these toxicities, thereby increasing the therapeutic index. This review article will be focused on the discussion of the most promising immunoproteasome specific inhibitors which have been developed in recent years. Particular attention will be devoted to the description of their mechanism of action, their structure-activity relationship, and their potential application in therapy. [ABSTRACT FROM AUTHOR]

Impaired fasting glucose and type 2 diabetes represent adverse events in patients with chronic myeloid leukemia (CML) treated with the second generation tyrosine kinase inhibitor nilotinib. An unweighted genetic risk score (uGRS) for the prediction of insulin resistance, consisting of 10 multiple single-nucleotide polymorphisms, has been proposed. We evaluated uGRS predictivity in 61 CML patients treated with nilotinib. Patients were genotyped for IRS1, GRB14, ARL15, PPARG, PEPD, ANKRD55/MAP3K1, PDGFC, LYPLAL1, RSPO3, and FAM13A1 genes. The uGRS was based on the sum of the risk alleles within the set of selected single-nucleotide polymorphisms. Molecular response (MR) 3.0 and MR 4.0 were achieved in 90% and 79% of patients, respectively. Before treatment, none of the patients had abnormal blood glucose. During treatment and subsequent follow-up at 80.2 months (range: 1–298), seven patients (11.5%) had developed diabetes that required oral treatment, a median of 14 months (range: 3–98) after starting nilotinib treatment. Twelve patients (19.7%) had developed prediabetes. Prediabetes/diabetes-free survival was significantly higher in patients with a uGRS <10 than in those with higher scores (100% vs. 22.8 ± 12.4%, p  <   0.001). Each increment of one unit in the uGRS caused a 42% increase in the prediabetes/diabetes risk (hazard ratio = 1.42, confidence interval: 1.04–1.94, p  = 0.026). The presence of more than 10 allelic variants associated with insulin secretion, processing, sensitivity, and clearance is predictive of prediabetes/diabetes development in CML patients treated with nilotinib. In clinical practice, uGRS could help tailor the best tyrosine kinase inhibitor therapy. [ABSTRACT FROM AUTHOR]

Telomeres are structures confined at the ends of eukaryotic chromosomes. With each cell division, telomeric repeats are lost because DNA polymerases are incapable to fully duplicate the very ends of linear chromosomes. Loss of repeats causes cell senescence, and apoptosis. Telomerase neutralizes loss of telomeric sequences by adding telomere repeats at the 3′ telomeric overhang. Telomere biology is frequently associated with human cancer and dysfunctional telomeres have been proved to participate to genetic instability. This review covers the information on telomerase expression and genetic alterations in the most relevant types of hematological diseases. Telomere erosion hampers the capability of hematopoietic stem cells to effectively replicate, clinically resulting in bone marrow failure. Furthermore, telomerase mutations are genetic risk factors for the occurrence of some hematologic cancers. New discoveries in telomere structure and telomerase functions have led to an increasing interest in targeting telomeres and telomerase in anti-cancer therapy. [ABSTRACT FROM AUTHOR]

The ongoing accumulation of knowledge raises hopes that understanding tumor metabolism will provide new ways for predicting, diagnosing, and even treating cancers. Some metabolic biomarkers are at present routinely utilized to diagnose cancer and metabolic alterations of tumors are being confirmed as therapeutic targets. The growing utilization of metabolomics in clinical research may rapidly turn it into one of the most potent instruments used to detect and fight tumor. In fact, while the current state and trends of high throughput metabolomics profiling focus on the purpose of discovering biomarkers and hunting for metabolic mechanism, a prospective direction, namely reprogramming metabolomics, highlights the way to use metabolomics approach for the aim of treatment of disease by way of reconstruction of disturbed metabolic pathways. In this review, we present an ample summary of the current clinical appliances of metabolomics in hematological malignancies. [ABSTRACT FROM AUTHOR]

Recently it has been shown that micro-Raman spectroscopy combined with multivariate analysis is able to discriminate among different types of tissues and tumoral cells by the detection of significant alterations and/or reorganizations of complex biological molecules, such as nucleic acids, lipids and proteins. Moreover, its use, being in principle a non-invasive technique, appears an interesting clinical tool for the evaluation of the therapeutical effects and of the disease progression. In this work we analyzed molecular changes in aged cultures of leukemia model U937 cells with respect to fresh cultures of the same cell line. In fact, structural variations of individual neoplastic cells on aging may lead to a heterogeneous data set, therefore falsifying confidence intervals, increasing error levels of analysis and consequently limiting the use of Raman spectroscopy analysis. We found that the observed morphological changes of U937 cells corresponded to well defined modifications of the Raman contributions in selected spectral regions, where markers of specific functional groups, useful to characterize the cell state, are present. A detailed subcellular analysis showed a change in cellular organization as a function of time, and correlated to a significant increase of apoptosis levels. Besides the aforementioned study, Raman spectra were used as input for principal component analysis (PCA) in order to detect and classify spectral changes among U937 cells. [ABSTRACT FROM AUTHOR]

The early diagnosis of malignancy is the most critical factor for patient survival and the treatment of cancer. In particular, leukemic cells are highly heterogeneous, and there is a need to develop new rapid and accurate detection systems for early diagnosis and monitoring of minimal residual disease. This study reports the utilization of molecular networks consisting of entire bacteriophage structure, displaying specific peptides, directly assembled with silver nanoparticles as a new Surface Enhanced Raman Spectroscopy (SERS) probe for U937 cells identification in vitro . A 9-mer pVIII M13 phage display library is screened against U937 to identify peptides that selectively recognize these cells. Then, phage clone is assembled with silver nanoparticles and the resulting network is used to obtain a SERS signal on cell-type specific molecular targets. The proposed strategy could be a very sensitive tool for the design of biosensors for highly specific and selective identification of hematological cancer cells and for detection of minimal residual disease in a significant proportion of human blood malignancy. [ABSTRACT FROM AUTHOR]

Tumor immunotherapy holds great promise in controlling multiple myeloma (MM) and may provide an alternative treatment modality to conventional chemotherapy for MM patients. For this reason, a major area of investigation is the development of cancer vaccines to generate myeloma-specific immunity. Several antigens that are able to induce specific T-cell responses are involved in different critical mechanisms for cell differentiation, inhibition of apoptosis, demethylation and proliferation. Strategies under development include infusion of vaccine-primed and ex vivo expanded/costimulated autologous T cells after high-dose melphalan, genetic engineering of autologous T cells with receptors for myeloma-specific epitopes, administration of dendritic cell/plasma cell fusions and administration expanded marrow-infiltrating lymphocytes. In addition, novel immunomodulatory drugs may synergize with immunotherapies. The task ahead is to evaluate these approaches in appropriate clinical settings, and to couple them with strategies to overcome mechanisms of immunoparesis as a means to induce more robust clinically significant immune responses. [ABSTRACT FROM AUTHOR]

Background aims. Filgrastim and lenograstim are the standard granulocyte colony-stimulating factor (G-CSF) agents for peripheral blood stem cell mobilization (PBSC) in patients who undergo autologous stem cell transplantation. Methods. To assess whether biosimilars are effective, we conducted a single-center, prospective study that included 40 consecutive de novo multiple myeloma patients who received cyclophosphamide 4 g/m² per day plus biosimilar filgrastim G-CSF to mobilize PBSC. These patients were compared with a group of 37 patients matched for age, diagnosis, previous chemotherapy and mobilization who had been treated with originator G-CSF. The mean number of CD34+ cells/µL in the peripheral blood was 199.6 ± 207.4 in the biosimilar and 192.8 ± 154.7 in the originator group (P = 0.87). The median number of CD34+ cells/kg recipient collected was 11.5 ± 5.8 and 12.3 ± 5.3 in the biosimilar and originator groups, respectively (P = 0.51). The mobilization failure rate was 2.5% and 2.7% in the biosimilar filgrastim and originator filgrastim cohorts (P = NS), respectively. Results. Twenty-nine patients in the biosimilar group and 28 patients in the originator group underwent autologous transplantation. There were no statistically significant differences between the biosimilar and originator G-CSF cohorts in terms of hematopoietic recovery parameters and transplant-related toxicities. Conclusions. The efficacy of bio-similar G-CSF appears to be equivalent to the reference G-CSF. [ABSTRACT FROM AUTHOR]

ZAP-70 is a marker of clinical outcome in chronic lymphocytic leukemia (CLL), however its assessment suffers from a lack of standardization consensus. To identify novel markers able to surrogate IGHV mutational status, CD19(+)CD5(+)- B -lymphocytes from 216 patients enrolled in a prospective study (ClinicalTrial.gov Identifier: NCT00917540 ), underwent gene expression profiling. Samples were split into CLL-Training ( n = 102) and CLL-Validation ( n = 114) sets, and an independent supervised analysis for IGHV mutational status was performed considering all genes with gene expression equal or above that of ZAP-70. Thirty-one genes (23 up- and 8 down-regulated) and 23 genes (18 up- and 5 down-regulated) satisfied these criteria in the CLL-Training and CLL-Validation sets, respectively, and 20 common genes (15 up and 5 down) were found to be differentially regulated in both sets. Two (SNORA70F, NRIP1) of the down-regulated and 6 (SEPT10, ZNF667, TGFBR3, MBOAT1, LPL, CRY1) of the up-regulated genes were significantly associated with a reduced risk of disease progression in both sets. Forcing the afore-mentioned genes in a Cox multivariate model together with IGHV mutational status, only CRY1 (HR = 2.3, 95% CI: 1.1–4.9, P = .027) and MBOAT1 (HR = 2.1, 95% CI: 1.1–3.7, P = .018) retained their independent prognostic impact, supporting the hypothesis that these genes may potentially act as surrogates for predicting IGHV mutational status. [ABSTRACT FROM AUTHOR]

Abstract: In 45, ≤60 years old patients with CLL and an adverse biologic profile, a front-line treatment with Fludarabine and Campath (Alemtuzumab®) was given. The overall response rate was 75.5%, the complete response rate (CR) 24.4% with the lowest CR rates, 16.7% and 8.3%, in 11q and 17p deleted cases. The 3-year progression-free survival (PFS) and overall survival were 42.5% and 79.9%, respectively. PFS was significantly influenced by CLL duration, beta2-microglobulin, and improved by post-remissional stem cell transplantation. Front-line fludarabine and alemtuzumab showed a manageable safety profile and evidence of a benefit in a small series of CLL patients with adverse biologic features. [Copyright &y& Elsevier]

Abstract: Bortezomib is the first proteasome inhibitor approved for the therapy of multiple myeloma (MM). Although Bortezomib has renovated the treatment of MM, a considerable proportion of subjects fail to respond to Bortezomib treatment and almost all patients relapse from this drug either alone or when used in combination therapies. However, the good clinical outcome of Bortezomib treatment in MM patients gave impulsion for the development of second generation proteasome inhibitors with the ambition of improving efficacy of proteasome inhibition, enhancing antitumor activity, and decreasing toxicity, as well as providing flexible dosing schedules and patient convenience. This review provides an overview of the role of oral proteasome inhibitors including Marizomib, Oprozomib, Delanzomib, chemical proteasome inhibitors, and cinnabaramides, in the therapy of MM, focusing on developments over the past five years. These emerging drugs with different mechanisms of action have exhibited promising antitumor activity in patients with relapsed/refractory MM, and they are creating chances to target multiple pathways, overcome resistance, and improve clinical outcomes, mainly for those subjects who are refractory to approved agents. Future steps in the clinical development of oral inhibitors include the optimization of the schedule and the definition of their antitumor activity in MM. [Copyright &y& Elsevier]

Abstract: mRNA/cDNA gene expression of both small leucine-rich proteoglycans decorin and biglycan was evaluated by PCR real time in lymphocytes collected from patients with chronic lymphocytic leukaemia (CLL) at different stages of disease and from healthy controls. Lymphocytes obtained from healthy controls showed no or very low levels of mRNA expression of both decorin and biglycan. Biglycan expression was very low in CLL patients, values being close to those of controls. On the contrary, decorin mRNA was clearly expressed in patients with early B-cell CLL, while a low expression was found in advanced clinical stages. Furthermore, a significant higher decorin expression was found in patients with non-progressive CLL type in comparison with patients with aggressive type of the disease. Decorin expression resulted especially high in the low-progressive low-risk patients. The synthesis of decorin was also assessed by Western blot analysis. The peculiar occurrence of decorin in the non-aggressive type of CLL is consistent with its suggested anti-oncogenic role. Intracellular Bcl-2 level does not correlate with decorin mRNA transcription, suggesting that a Bcl-2 independent anti-cancer mechanism may occur. The measurement of galactosamine-containing proteoglycans concentration in plasma confirmed decorin expression results, with significant differences between CLL patients and controls. Significant changes were also seen between groups of patients of Rai stage 0 with recent diagnosis (less than 5 years, from analysis), (low amount of decorin) and less recent diagnosis (more than 5 years), (high amount of decorin). [Copyright &y& Elsevier]

Monoclonal gammopathy of undetermined significance (MGUS) is a pre-malignant abnormality of plasma cells, with increased serum levels of immunoglobulins. Patients with MGUS may evolve to multiple myeloma through a multistep process including deregulated gene expression. microRNAs are small non-coding RNA molecules involved in post-transcriptional regulation of crucial biological processes, such as morphogenesis, cell differentiation, apoptosis, and cancer. This study aimed to evaluate microRNA expression on peripheral lymph-monocytes from MGUS subjects compared with healthy controls using qPCR arrays. Blood samples were collected by venipuncture from fifteen, newly diagnosed MGUS patients and fifteen healthy subjects. A further group (validation group) of six newly diagnosed MGUS patients and five healthy control were enrolled for the validation of miRNAs and their mRNAs target. The study was conducted performing miProfile miRNA qPCR arrays, followed by validation of miRNAs and related mRNA targets through RT-qPCR. The functional interaction between microRNAs and target gene were obtained by Ingenuity Pathways Analysis (IPA). IPA network analysis identified only molecules and relationships experimentally observed in peripheral lymphomonocytes. The following miRNAs :133a-3p, 16−5p, 291−3p, 23a-3p, 205−5p, 17−5p, 7a-5p, 221−3p, 30c-5p, 126a-3p,155−5p, let-7a-5p and 26a-5p, involved in the regulation of genes with a role in lymphocyte homeostasis, cell proliferation, apoptosis, and multiple myeloma (MM) progression, were differently expressed in MGUS with respect to healthy subjects. This miRNA signature and its relative targets could be considered for the formulation of new therapeutic strategies in the prophylaxis or treatment of monoclonal gammopathies. [ABSTRACT FROM AUTHOR]