Azacitidine in the front-line treatment of therapy-related myeloid neoplasms: a multicenter case series.

BACKGROUND/AIM: A continued increase in the incidence of therapy-related myeloid neoplasms (t-MN) is expected due to the improvement of chemotherapeutic treatments for solid and haematological malignancies. The use of 5-azacytidine (AZA) is emerging in these patients. We, therefore, analyzed the outcome of patients with t-MN ineligible for intensive chemotherapy treated in the front-line with AZA. PATIENTS AND METHODS: We retrospectively collected clinical data from consecutive patients with t-MN treated in the front-line with AZA at five Haematology Centers. Response to therapy, overall survival (OS) and safety were considered. RESULTS: The overall response rate was of 35.7% with a median OS of 9.6 months. Patients who were heavily pre-treated for their primary malignancy (more than 3 lines of chemotherapy) presented a significant inferior OS (4.9 months). The principal reported toxicity was haematological with severe infections occurring in a minority of patients. Fatigue was the most common extra-haematological toxicity. CONCLUSION: New aspects emerged on the management of t-MN. AZA may represent a reasonable choice for patients ineligible for intensive treatment, with the exception of heavily pre-treated patients who presented -anyway- a worse outcome.

Bendamustine plus rituximab for relapsed or refractory diffuse large B cell lymphoma: a retrospective analysis.

For patients with relapsed or refractory diffuse large B cell lymphoma (DLBCL) who are not eligible for intensive chemotherapy because of comorbidities, advanced age, or relapse after heavy salvage regimens, treatment options are very limited and prognosis is poor. We retrospectively analyzed 29 patients with relapsed/refractory DLBCL treated with combination bendamustine plus rituximab (BR) between July 2010 and January 2014 to evaluate overall response rate (ORR), progression-free survival (PFS), duration of response (DOR) and treatment safety. Twenty-eight patients were available for this analysis. ORR was 50% (14 patients), with 39.3% CR (11 patients), and 10.7% PR (3 patients). SD was reported in 2 patients (7.2%) and PD in 12 patients (42.8%). At the median follow up of 8 months (range 1-37.4 months), the median PFS was 8 months for all patients (95% CI 5.5-26.6). The median DOR was 24.7 months (95% CI 3.2-24.7). Grade 3/4 toxicity observed included hematologic events: lymphopenia (42.8%), neutropenia (32.1%), anemia (17.2%), and thrombocytopenia (14.2%). BR can be considered to have a role in the treatment of patients with relapsed/refractory DLBCL with limited therapeutic options, in that it can induce long-term remission in some patients with an acceptable toxicity profile.

Challenges and opportunities of microRNAs in lymphomas.

MicroRNAs (miRNAs) are small non-coding RNAs that control the expression of many target messenger RNAs (mRNAs) involved in normal cell functions (differentiation, proliferation and apoptosis). Consequently their aberrant expression and/or functions are related to pathogenesis of many human diseases including cancers. Haematopoiesis is a highly regulated process controlled by a complex network of molecular mechanisms that simultaneously regulate commitment, differentiation, proliferation, and apoptosis of hematopoietic stem cells (HSC). Alterations on this network could affect the normal haematopoiesis, leading to the development of haematological malignancies such as lymphomas. The incidence of lymphomas is rising and a significant proportion of patients are refractory to standard therapies. Accurate diagnosis, prognosis and therapy still require additional markers to be used for diagnostic and prognostic purpose and evaluation of clinical outcome. The dysregulated expression or function of miRNAs in various types of lymphomas has been associated with lymphoma pathogenesis. Indeed, many recent findings suggest that almost all lymphomas seem to have a distinct and specific miRNA profile and some miRNAs are related to therapy resistance or have a distinct kinetics during therapy. MiRNAs are easily detectable in fresh or paraffin-embedded diagnostic tissue and serum where they are highly stable and quantifiable within the diagnostic laboratory at each consultation. Accordingly they could be specific biomarkers for lymphoma diagnosis, as well as useful for evaluating prognosis or disease response to the therapy, especially for evaluation of early relapse detection and for greatly assisting clinical decisions making. Here we summarize the current knowledge on the role of miRNAs in normal and aberrant lymphopoiesis in order to highlight their clinical value as specific diagnosis and prognosis markers of lymphoid malignancies or for prediction of therapy response. Finally, we discuss their controversial therapeutic role and future applications in therapy by modulating miRNA.

Target therapies in pancreatic carcinoma.

Pancreatic ductal adenocarcinoma (PDAC) occurs in the majority of cases with early locoregional spread and distant metastases at diagnosis, leading to dismal prognosis and limited treatment options. Traditional cytotoxic chemotherapy provides only modest benefit to patients with PDAC. Identification of different molecular pathways, overexpressed in pancreatic cancer cells, has provided the opportunity to develop targeted therapies (monoclonal antibodies and small-molecule inhibitors) and peculiar new class of taxanes with a crucial therapeutic role in this cancer setting. A phase III trial has shown that erlotinib in combination with gemcitabine was clinically irrelevant and skin toxicity can be a positive prognostic factor. Moreover, the combination of cetuximab or erlotinib with radiotherapy in advanced pancreatic cancer has shown to be synergistic and a reversal of radio-resistance has been suggested by inhibition of VEGF/EGFR pathway. To overcome EGFR-inhibition therapy resistance several alternative pathways targets are under investigation (IGF- 1R, MMPs, Hedgehog proteins, m-TOR, MEK, COX-2) and provide the rationale for clinical use in phase II/III studies. Also nab-paclitaxel, a new taxanes class, uses high pancreatic albumin-binding protein SPARC levels to act in cancer cells with a less toxic and more effective dose with respect to classic taxanes. Understanding of molecular pathogenesis of pancreatic adenocarcinoma continues to expand. However, many promising data in preclinic and phase I/II trials did not yield promise in phase III trials, suggesting that identification of predictive biomarkers for these new agents is mandatory. The knowledge of biologic and molecular aspects of pancreatic cancer can be the basis for future therapeutic developments.

Targeted strategies in the treatment of primary gastric lymphomas: from rituximab to recent insights into potential new drugs.

Primary gastric non-Hodgkin's lymphomas (PG-NHL) are the most common extranodal lymphomas, representing between 47% and 74% of all gastrointestinal lymphoma cases. In Western countries two histological types, diffuse large B-cell (DLBC) NHL and mucosa-associated lymphoid tissue (MALT) NHL, are more frequently represented, accounting for the majority of gastric tumors after adenocarcinoma. For several years treatment of these PG lymphomas consisted of surgery, chemotherapy and radiotherapy, alone or in combination. In the last two decades however, advances in our understanding of their pathogenesis and biology have changed the treatment strategy, at least as regards the early stages of disease. In addition to making tumor regression possible through the eradication of Helicobacter pylori, which is considered the main pathogenic agent, this understanding has also provided a solid rationale to assess the efficacy of targeted therapy, namely of drugs which interfere with specific molecules expressed by tumor cells or are involved in key growth pathways of these lymphomas. In particular, rituximab, a monoclonal anti-CD20 antibody, radioimmunotherapy, the first-generation proteasome inhibitor bortezomib and lenalidomide have been evaluated. Despite significant antitumor activity in this subset of NHL and manageable toxicity, many questions still remain however about the optimal dose, the best administration schedule and their combination with conventional chemotherapy. This review focuses on the pathogenesis of PG-MALT and DLBC lymphomas, and discusses the results of clinical trials on the impact of new agents on prognosis and survival in these patients, considering also potential new therapautic targets.

Changes in angiogenesis and hypoxia-inducible factor-1α protein expression in relapsed/refractory indolent non-Hodgkin lymphomas.

Angiogenesis is involved in the pathogenesis and progression of non-Hodgkin lymphomas (NHL), and hypoxia-inducible factor-1α (HIF-1α, also termed HIF1A) might contribute to this process. Currently, there is no direct evidence that the clinical progression of indolent NHL is associated with angiogenesis, and the expression of HIF-1α at recurrence is unknown. Matched lymph node biopsies at diagnosis and recurrence of relapsed/refractory indolent NHL patients were analysed by immunohistochemical and morphometric analysis. We observed an increased vascular network and HIF-1α protein expression in the second biopsy, providing direct evidence that angiogenesis is an essential process for disease progression.

Waldenström's macroglobulinemia. An overview of its clinical, biochemical, immunological and therapeutic features and our series of 121 patients collected in a single center.

Waldenström's macroglobulinemia (WM) is defined as a B-cell lymphoproliferative disorder characterized by lymphoplasmacytic infiltration of the bone marrow associated with a monoclonal IgM component in the serum. Its clinical presentation is marked by diffuse clonal cell expansion, as well as by the physical and chemical properties of the monoclonal component, its autoantibody activity and possible tissue deposition. Initiation of treatment is not determined by the monoclonal IgM level, nor the extent of bone marrow infiltration, but confined to symptomatic patients. Their median overall survival ranges from 5 to 10 years. Poor outcome predictors include advanced age, low hemoglobin levels, low platelet count, high ß2-microglobulin and high concentration of the serum monoclonal component. First-line therapeutic approaches include alkylating agents (chlorambucil, melphalan, cyclophosphamide), nucleoside analogs (fludarabine, cladribrine), and rituximab, whether singly or combined. Thalidomide-based regimens and bortezomib have also been assessed, and new agents such as bendamustine and everolimus are being investigated. We review these general features and describe our series of 121 patients with clearly established WM.

Biological functions and therapeutic use of erythropoiesis-stimulating agents: perplexities and perspectives.

Randomized clinical studies, carried out in patients with haematological malignancies and with solid tumours, have consistently demonstrated that treatment with recombinant human erythropoietin (Epo) increases haemoglobin levels, reduces blood transfusion requirements, and improves the quality of life. In addition, identification of erythropoietin receptor (EpoR) expression on many types of non-erythroid and cancer cells has spurred an interest in the extra-haematological activities of Epo itself and other erythropoiesis-stimulating agents (ESAs). Epo and its derivatives have emerged as major tissue-protective cytokines in ischaemic and degenerative damage of cardiovascular, neurological and renal diseases, while their angiogenetic and immunomodulatory properties indicate that their therapeutic potential may extend well beyond erythropoiesis alone. Both preclinical and clinical data, however, have suggested that they may contribute to tumour progression and prejudice survival when administered to anaemic cancer patients, though the results are equivocal and the assumed mechanisms by which tumour growth could be promoted are not fully understood. While these findings offer new perspectives, they nonetheless demand caution in the employment of ESAs. Further, well-designed experimental and clinical studies are warranted.

Long-term survival in multiple myeloma: a single-center experience.

In patients with multiple myeloma the median overall survival is now approaching 5 years, following the introduction of autologous stem cell transplantation and targeted therapies. However, patients receiving conventional chemotherapy who have survived 10 years or longer have been repeatedly reported in the literature. From 723 patients with multiple myeloma seen in our department from January 1981 to June 2007, we selected 21 long-term (> or =10 years) survivors (2.9%) who had been treated with conventional chemotherapy. Potentially favourable prognostic factors, common to most patients, were: age < or =65 years; response to first-line chemotherapy; absence of Bence-Jones proteinuria; prolonged duration of response or stable disease irrespective of the primary regimen; maintenance therapy with interferon-alpha. The use of prognostic factors to identify a subset of low-risk patients could be of assistance in the selection of targeted treatments and the elucidation of poorly known features of myeloma biology.

Identification of an antigenic and immunogenic motif expressed by two 7-mer rituximab-specific cyclic peptide mimotopes: implication for peptide-based active immunotherapy.

Two 7-mer cyclic peptides-Rp15-C and Rp13-C-which bear the antigenic motif recognized by the anti-CD20 mAb rituximab, but have different motif-surrounding amino acids, show a comparable avidity for rituximab and inhibit the binding of rituximab to raft-associated CD20 and rituximab-induced membrane ceramide on human lymphoid Daudi cells. Their immunogenic profiles differed: Abs recognizing CD20 were induced in two and five of five BALB/c mice immunized with Rp15-C and Rp13-C, respectively. Analysis of immunogenic motif, performed by panning a 7-mer phage-display peptide library with purified anti-peptide IgGs, showed that the motif defined by anti-Rp15-C mostly included amino acids surrounding the rituximab-specific antigenic motif , whereas that defined by anti-Rp13-C was . These data indicate that their motif-surrounding amino acids can markedly influence the specificity of Abs, even when elicited with a short 7-mer peptide. Because these anti-peptide Abs are of IgG isotype, their specificity is likely to reflect how peptides are processed at the T cell level and suggest that, within a short peptide, the motifs defined by T cells during the initial phase and upon their stimulation may be different. Our findings may account for the failure of most forms of peptide-based immunotherapy in cancer and autoimmune diseases in which anti-mimotope Abs are expected to play a relevant therapeutic effect. They also suggest strategies to implement the specificity of peptide-induced Abs against the target Ag.

Loss of inhibitory semaphorin 3A (SEMA3A) autocrine loops in bone marrow endothelial cells of patients with multiple myeloma.

Vascular endothelial growth factor165 (VEGF165) and semaphorin3A (SEMA3A) elicit pro- and antiangiogenic signals respectively in endothelial cells (ECs) by binding to their receptors VEGFR-2, neuropilin-1 (NRP1), and plexin-A1. Here we show that the VEGF165-driven angiogenic potential of multiple myeloma (MM) ECs is significantly higher than that of monoclonal gammopathy of undetermined significance (MGUS) ECs (MGECs) and human umbilical vein (HUV) ECs. This is probably due to a constitutive imbalance of endogenous VEGF165/SEMA3A ratio, which leans on VEGF165 in MMECs but on SEMA3A in MGECs and HUVECs. Exogenous VEGF165 induces SEMA3A expression in MGECs and HUVECs, but not in MMECs. Moreover, by counteracting VEGF165 activity as efficiently as an anti-VEGFR-2 antibody, exogenous SEMA3A restrains the over-angiogenic potential of MMECs. Our data indicate that loss of endothelial SEMA3A in favor of VEGF165 could be responsible for the angiogenic switch from MGUS to MM.

Antiangiogenesis by chemotherapeutic agents.

Many tumors are not curable because current treatments primarily target the tumor cells. Intratumoral endothelial cells, on the other hand, proliferate rapidly and are sensitive to the cytotoxic effects of chemotherapeutic agents. This review summarizes the literature concerning the antiangiogenic effects of these agents when administered alone or in combination with other angiogenesis inhibitors.

CXCR3-binding chemokines in multiple myeloma.

The CXC chemokines I-TAC, Mig and IP10 and their receptor CXCR3 are associated with advanced-stage tumor and contribute to tumor progression, invasion and metastasis. The current study was designed to determine the expression of CXCR3 on four multiple myeloma (MM) cell lines and bone marrow plasma cells from 20 MM patients. Cell functions related to progression, such as tyrosine-kinase phosphorylation, proliferation, chemotaxis and matrix metalloproteinase-2 (MMP-2), and MMP-9 secretion were also investigated following the CXCR3/chemokine interaction. fluorescence activated cell sorting analysis revealed that three cell lines (75%) and 18 patients (90%) express the CXCR3 molecule. We demonstrated both in cell lines and fresh plasma cells that I-TAC, Mig and IP10 are able to induce tyrosine-kinase phosphorylation and chemotaxis, but not proliferation, and to increase the MMP-2 and MMP-9 gelatinolytic activity in the cell conditioned medium. Data suggest that CXCR3/chemokine loop may be important for progression of MM in terms of intramedullary and extramedullary dissemination.

Angiogenesis in acute and chronic lymphocytic leukemia.

The bone marrow microenvironment plays a crucial role in leukemogenesis. Recent studies suggest that its vascularity changes significantly during this process and that angiogenic factors are of major importance in leukemia. This review summarizes the literature concerning the relationship between angiogenesis and the progression of acute and chronic lymphocytic leukemia. It is becoming increasingly evident that agents which interfere with angiogenesis also block tumor progression and anti-angiogenic management has become a prominent aspect of pre-clinical and clinical assessment. Recent applications of anti-angiogenic agents which interfere with or block leukemia progression are reviewed.

Endothelial cells in the bone marrow of patients with multiple myeloma.

Endothelial cells (EC) were extracted through a lectin-based method from bone marrow of 57 patients with active multiple myeloma (MM) and compared with their healthy quiescent counterpart, human umbilical vein EC (HUVEC). MMECs exhibit specific antigens that indicate ongoing angiogenesis and embryo vasculogenesis; solid intercellular connections, hence stability of MM neovessels; and frequent interactions with plasma cells, hence tumor dissemination. They show heterogeneous antigen expression, hence existence of subsets. Their main genetic markers are indicative of a vascular phase. They show intrinsic angiogenic ability, because they rapidly form a capillary network in vitro, and extrinsic ability, because they generate numerous new vessels in vivo. They vividly secrete growth and invasive factors for plasma cells. They signal through kinases mandatory for development of neovascularization. Ultrastructurally, they are abnormal and show metabolic activation, like tumor ECs. Thalidomide heavily interferes with their functions. Vasculogenesis and angiogenesis might contribute to the MM vascular tree and progression, in the form of growth, invasion, and dissemination. In view of the heterogeneity of the antigenic phenotype of MMECs, a mixture (or a sequence) of antiangiogenic agents coupled with thalidomide would seem plausible for the biologic management of MM.

Alpha(v)beta(3) integrin engagement enhances cell invasiveness in human multiple myeloma.

BACKGROUND AND OBJECTIVES: In multiple myeloma (MM), the mechanisms used by plasma cells to invade locally and metastasize are thought to be similar to those developed by solid tumors and include cell proliferation and secretion of extracellular matrix (ECM) degrading enzymes following adhesion to ECM proteins. We studied these mechanisms in fresh bone marrow plasma cells of patients with MM after adhesion to the ECM proteins vitronectin (VN) and fibronectin (FN). DESIGN AND METHODS: The ability of bone marrow plasma cells to adhere to VN and FN and the consequent formation of focal adhesion plaques on the cell surface, their composition and phosphorylation of several signal transduction proteins, cell proliferation and secretion of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) and urokinase-type plasminogen activator (uPA) were studied. RESULTS: Plasma cells adhered to immobilized VN and FN. Adhesion was fully prevented by neutralizing anti-avb3 integrin antibody. Integrin engagement caused aggregation of the plaques, which contained the b3 integrin subunit, some cytoskeletal proteins, tyrosine kinases, the Grb-2 adapter protein, and mitogen-activated protein (MAP) kinase. Free and immobilized VN and FN stimulated cell proliferation and the production and the release of uPA, and increased the release of the activated forms of MMP-2 and MMP-9 in an avb3 integrin-dependent manner. INTERPRETATION AND CONCLUSIONS: This ability of myeloma plasma cells to interact with VN and FN via avb3 integrin engagement suggests a novel mechanism for their invasion and spreading, since this interaction allows them to adhere to the substratum and enhances their proliferation and protease secretion.

Docetaxel versus paclitaxel for antiangiogenesis.

Cytoskeleton-toxic chemotherapeuticals, such as vinblastine and paclitaxel, display antiangiogenic activity. This study was designed to compare paclitaxel to its analog docetaxel and assess their doses still antiangiogenic in vitro and in vivo. Human endothelial cell functions involved in angiogenesis, namely proliferation, chemotaxis, morphogenesis, and secretion of matrix metalloproteinase-2 (MMP-2), MMP-9, and urokinase-type plasminogen activator (uPA) were studied in vitro upon exposure to docetaxel and paclitaxel, whereas their effect on angiogenesis was studied in vivo by using the chick embryo chorioallantoic membrane (CAM) model. Proliferation of mouse embryo fibroblasts and human Kaposi's sarcoma, breast and endometrial carcinoma, and lymphoid tumor cells was also studied. In vitro, 0.5, 0.75, and 1 nM docetaxel and 2, 3, and 4 nM paclitaxel, i.e., non-cytotoxic doses, impacted all endothelial cell functions, but not protease secretion, in a dose-dependent fashion, whereas they did not affect the proliferation of other cells, except those of Kaposi's sarcoma. No apoptosis was induced by 0.5 nM docetaxel and 2 nM paclitaxel, and moderate apoptosis was induced by 1 nM docetaxel and 4 nM paclitaxel. The antiangiogenic effect rapidly disappeared on drug suspension and was accompanied ultrastructurally by thin lesions of cytoskeleton in the form of slight and equally reversible depolymerization and accumulation of microfilaments. Massive endothelial cell apoptosis with evident cytotoxicity and irreversibility were associated with 2 nM docetaxel and 5 nM paclitaxel, although these higher doses were ineffective on other cells except Kaposi's sarcoma cells. In vivo, 1, 2, and 3 nM docetaxel and 4, 8, and 12 nM paclitaxel displayed a dose-dependent antiangiogenic activity. We suggest that very low docetaxel and paclitaxel doses selectively cause organic and functional damage of endothelial cells and that docetaxel is four times stronger. Their antiangiogenic activity could be applied to treat Kaposi's sarcoma and cancers.