CD200 expression in patients with Multiple Myeloma: another piece of the puzzle.

CD200 is a relatively ubiquitously expressed molecule that plays a role in cancer immune evasion through interaction with its receptors. High expression levels of CD200 have been described in different human malignancies. For example, CD200 has been shown to be targeted after RAS/RAF/MEK/ERK activation in melanoma. Here we present the analysis of CD200 expression in human Multiple Myeloma (MM) samples. We found that CD200-positive cells express ERK and p-ERK. Moreover, UO126, a MEK inhibitor, reduces CD200 expression. Furthermore, we observe that CD200-positive cells show reduced immunogenicity compared to normal lymphocytes and that such immunogenicity increases when UO126 is used. We therefore hypothesize that CD200 expression in MM could suppress antitumor response and that anti-CD200 treatment might be therapeutically beneficial in CD200-expressing tumors.

Disulfiram, an old drug with new potential therapeutic uses for human hematological malignancies.

Disulfiram (DSF) is an aldehyde dehydrogenase inhibitor currently used for the treatment of alcoholism. Here, we show that multiple myeloma (MM) cell lines and primary cells from newly diagnosed and relapsed/resistant patients affected by MM, acute myeloid and lymphoblastic leukemia are significantly sensitive to DSF alone and in combination with copper. These effects are present at doses lower than those achievable in vivo after DSF standard administration. The cytotoxic effect achieved by this treatment is comparable to that obtained by conventional chemotherapy and is absent in normal hematopoietic cells. In addition, we found that DSF plus copper induces loss of mitochondrial membrane potential, triggers reactive oxygen species (ROS) production and activates executioner caspases. DSF-copper-induced apoptosis and caspases activation are strongly reversed by antioxidant N-acetylcysteine, thus indicating a critical role of ROS. These results might suggest the use of the old drug DSF, alone or in combination with copper, in the treatment of hematological malignancies.

NF-κB localization in multiple myeloma plasma cells and mesenchymal cells.

Several reports demonstrated that the activation of Nuclear Factor-kappa B NF-κB is essential for the pathogenesis of multiple myeloma (MM). We analyzed the nuclear localization of NF-κB in MM-cells derived from 60 different patients with MM at presentation and in relapse, as well as in three myeloma cell lines. Nuclear localization (the active form) of NF-κB was detected in only one MM-sample from a refractory patient and in two samples from relapsed patients, while all the other samples, including the MM-cell lines, almost exclusively express the cytoplasmic (inactive) form of NF-κB. In mesenchymal cells from MM-patients NF-κB was clearly present in the nucleus. In addition, the proteasome inhibitor Bortezomib, which is described to antagonize NF-κB activity, had a consistent antitumor activity against both chemoresistant and chemosensitive MM-cells, regardless the NF-κB localization, thus suggesting the existence of other molecular targets of proteasome inhibitors in MM.

Pleuric presentation of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue: a case report and a review of the literature.

A primary pleural marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT) is a very rare eventuality. Here, we report a rare case of MALT lymphoma arising in the pleura and update the literature on this topic. A 74-year-old female was hospitalized for persistent cough and weakness. A chest radiograph and total-body CT scan showed only large right-sided pleural effusion, and the coexistence of pleural thickening. Video-assisted thoracoscopic exploration and a talc pleurodesis were performed and microscopic and immunohistochemical findings showed that the tumor was a pleural MALT lymphoma. The patient received immunotherapy with Rituximab and obtained a good response that lasted 2 years. To the best of our knowledge, only seven cases of primary pleural MALT lymphoma have been documented until recently, mostly from Japan with a mean age for all patients of 60.5 years. The pathogenesis of MALT lymphomas remains unclear, although a possible chronic antigenic stimulation by microbial pathogens and/or autoantigens has been hypothesized. Surgical resection was performed in most cases, and some patients received postoperative chemotherapy or immunotherapy. The clinicopathologic characteristics and management of this extremely rare disease are also discussed.

Antitumor activity of bortezomib alone and in combination with TRAIL in human acute myeloid leukemia.

Acute myeloid leukemia (AML) is a malignant disease characterized by abnormal proliferation of clonal precursor cells. Although different strategies have been adopted to obtain complete remission, the disease actually progresses in about 60-70% of patients. Bortezomib has been used in multiple myeloma and other lymphoid malignancies because of its antitumor activity. Here we examined the sensitivity of bone marrow cells from AML patients (34 patients: 25 newly diagnosed, 4 relapsed, 5 refractory) to bortezomib alone or in combination with TRAIL, a member of the TNF family that induces apoptosis in tumor cells while sparing normal cells. Bortezomib induced cell death in blasts from each patient sample. The cytotoxic effect was dose- and time-dependent (concentration from 0.001 to 10 microM for 24 and 48 h) and was associated with a downregulation of Bcl-xL and Mcl-1, an upregulation of TRAIL-R1, TRAIL-R2, p21, activation of executioner caspases and a loss of the mitochondrial membrane potential. Moreover, low doses of bortezomib primed TRAIL-resistant AML cells for enhanced TRAIL-mediated killing. These results suggest that a combination of proteasome inhibitors and TRAIL could be effective for treating AML patients, even patients who are refractory to conventional chemotherapy.

Intermediate dose etoposide plus G-CSF 16 g/kg is more effective than cyclophosphamide 4 g/m(2) plus G-CSF 10 g/kg in PBSC mobilization of lymphoma patients.

We designed intermediate dose etoposide + G-CSF 16 microg/kg as a Peripheral Blood Stem Cell (PBSC) mobilization schedule suitable for outpatient administration. Forty-one Lymphoma patients received intermediate dose etoposide (200 mg/m(2) i.v. day +1, +2, +3) +G-CSF 16 microg/kg/day. Results of PBSC mobilization in these patients were compared with those of a group of 37 lymphoma patients mobilized using cyclophosphamide (CTX) at dosage of 4 g/m(2) + G-CSF 10 microg/kg/die. Mean peak of CD34+ cells achieved in P.B. and total CD34+ cells harvested were higher in patients mobilized with intermediate dose etoposide (p = 0.003 and p = 0.004, respectively). After transplantation recovery of polymorphonucleate neutrophils (PMN) > 0.5 x 10(9)/L did not differ significantly between groups: 11.7 days in intermediate dose etoposide group and 11.5 days in CTX group (p = 0.7). Intermediate dose etoposide + G-CSF 16 microg/kg resulted in a maximum length of neutropenia (PMN < 0.5 x 10(9)/L) of 2 days and neutropenic fever was registered during only 3/41 courses (7.3%). Intermediate dose etoposide + G-CSF 16 microg/kg is a highly effective mobilizing therapy, further, it has the advantage of low hematologic toxicity and can be easily administered as outpatient treatment.

BCR-ABL nuclear entrapment kills human CML cells: ex vivo study on 35 patients with the combination of imatinib mesylate and leptomycin B.

The BCR-ABL oncoprotein of chronic myelogenous leukemia (CML) localizes to the cell cytoplasm, where it activates proliferative and antiapoptotic signaling pathways. We previously reported that the combination of the ABL kinase inhibitor imatinib mesylate (IM) and the nuclear export inhibitor leptomycin B (LMB) traps BCR-ABL inside the nucleus, triggering the death of the leukemic cells. To evaluate the efficacy of the combination of IM and LMB on human cells we collected CD34-positive cells from 6 healthy donors and myeloid progenitors from 35 patients with CML. The sequential addition of IM and LMB generated the strongest reduction in the proliferative potential of the leukemic cells, with limited toxicity to normal myeloid precursors. Furthermore, nested reverse transcriptase-polymerase chain reaction (RT-PCR) analysis on colonies representative of each experimental condition demonstrated that the combination of IM and LMB was the most effective regimen in reducing the number of BCR-ABL-positive colonies. The efficacy of the 2-drug association was independent of the clinical characteristics of the patients. Our results indicate that strategies aimed at the nuclear entrapment of BCR-ABL efficiently kill human leukemic cells, suggesting that the clinical development of this approach could be of significant therapeutic value for newly diagnosed and IM-resistant CML patients.

Treatment of symptomatic patients with essential thrombocythemia: effectiveness of anagrelide.

We prospectively evaluated the effect of anagrelide (ANA) on platelets, PF4, F1+2, PAP, PAI-1, and TFPI and erythromelalgia in patients with essential thrombocythemia (ET) receiving anti-aggregants both pre- and post-ANA. At first, we observed a successful reduction of platelets, which was associated with normalization of platelet coagulant and endothelial function and disappearance of erythromelalgia. Secondly, we found a correlation between PF4 and TFPI and between TFPI and thrombosis, suggesting that erythromelalgia may be caused by platelet-mediated endothelial activation. These data may indicate that ANA may be efficacy in the treatment of symptomatic patients with ET.

Familial B-cell chronic lymphocytic leukemia in a population of patients from Southern Italy.

We investigated the prevalence of chronic lymphocytic leukemia (CLL) in 9650 relatives of 510 CLL patients from 5 different regions (Apulia, Basilicata, Campania, Calabria, and Sicily) of Southern Italy. Data collection included a family history questionnaire. In our series of 510 CLL patients, 53 families with 2 or more individuals who had chronic lymphoproliferative disease (CLD) or other hematological malignancies were identified. In these families, 27 cases of CLL, 10 of indolent non-Hodgkin's lymphoma, and 7 of multiple myeloma were identified in relatives of CLL probands. Twenty-two relatives developed hematological malignancies other than CLD (19, acute leukemia; 3, chronic myeloid leukemia). In this study the prevalence of CLD in relatives of 510 CLL patients was 8.6% (44/510), and the prevalence of CLL in the same series was 5.2% (27/ 510). Considering the presence of clusters of individuals with hematological malignancies, overall our series contained 4 families showing a cluster with more than 2 cases. The most frequent pattern of affected family members was represented by 39 families (39/53 [73%]) with affected siblings or cousins only. Twenty siblings had CLL. The other families showed a multigenerational pattern with an affected parent-offspring relationship in only 11 (21%) of the cases and with a combination of the first 2 categories in 3 (6%) of the families. In 8 families belonging to both the last 2 mentioned groups, the affected offspring had an earlier disease onset than their parents, suggesting anticipation. We estimated the size and examined the pattern of familial aggregation of hematological malignancies, in particular CLL/CLD, in a specific geographical area. CLL was the most frequent disease in relatives, mainly siblings, of our CLL patients. Our results may be a contribution to the characterization of the epidemiological distribution pattern of CLL.

T cell receptor delta-chain gene rearrangement in a novel case of adult NK cell leukemia.

Malignancies arising from natural killer (NK) cells are being increasingly recognized as distinct clinicopathological entities. We here report the characteristics of a peculiar case of NK-cell acute leukemia with unusual agranular morphology and rearrangement of the T-cell receptor (TCR) delta-chain gene.

Flow cytometric detection of aneuploid CD38(++) plasmacells and CD19(+) B-lymphocytes in bone marrow, peripheral blood and PBSC harvest in multiple myeloma patients.

DNA aneuploidy has been used as a genetic marker of malignancy in multiple myeloma (MM). CD38 and CD138 expression and absence of CD22 and CD19 may define plasmacells (PC). Several authors support evidences of circulating plasmacells, and their role in relapse after autologous stem cell transplantation has been hypothesised. The existence of B-lymphocytes belonging to the myeloma clone is still controversial. If CD19 or CD22 positive B-lymphocytes are part of the myeloma clone, there should be evidence of myeloma-specific genetic markers in this population. Using DNA content measurement in combination with CD19 or CD38 detection in a multiparametric flow cytometry analysis, we studied bone marrow and peripheral blood of 10 aneuploid MM patients. In the bone marrows of all these 10 aneuploid patients (100%), we detected CD38(++) aneuploid plasmacells ( 27 +/- 17%, mean +/- S.D.) and a small number of CD19(+) aneuploid lymphocytes ( 0.11 +/- 0.074%). In 100% of these patients, we also detected CD38(++) aneuploid circulating plasmacells ( 0.6 +/- 0.9 %) and a small number of CD19(+) aneuploid lymphocytes (0.03 +/- 0.04%). In this study, we detected aneuploid CD19(+) lymphocytes and CD38(++) plasmacells in bone marrow and peripheral blood of all MM patients. A crucial role for the detection of aneuploid CD19(+) cells was played by the acquisition of a sufficient number of CD19(+) lymphocytes by using a "live gate" acquisition and "continuous gating" analysis. With the techniques used in this study, it was possible to detect aneuploid B lymphoid cells among normal diploid B cells. The significance of this finding is controversial and opened to different interpretations.

Acute promyelocytic leukemia during pregnancy: report of 3 cases.

Acute promyelocytic leukemia (APL) is characterized by onset at a young age and a life-threatening hemorrhagic diathesis, which is attributed to a disseminated intravascular coagulation (DIC)-like coagulopathy. The discovery of all-trans-retinoic acid has changed the course of APL treatment by reducing the onset of DIC and inducing a complete and durable remission in more than 90% of patients. The occurrence of APL during pregnancy is not a frequent event, but the management of these patients raises many therapeutic and ethical dilemmas and requires a careful clinical case evaluation of fetal and maternal risk, coagulation status, the parents' wishes, and therapeutic options. Here we describe 3 patients with APL diagnosed during pregnancy. Clinical data and the therapeutic approaches are presented. In the discussion, we analyze clinical decisions and therapeutic options and compare our cases with those found in the literature.

Allogeneic compared with autologous stem cell transplantation in the treatment of patients younger than 46 years with acute myeloid leukemia (AML) in first complete remission (CR1): an intention-to-treat analysis of the EORTC/GIMEMAAML-10 trial.

In the European Organization for Research and Treatment of Cancer Leukemia Group and Gruppo Italiano Malattie Ematologiche dell' Adulto (EORTC-LG/GIMEMA) acute myeloid leukemia (AML)-10 trial, patients in first complete remission (CR1) received a single intensive consolidation (IC) course. Subsequently, those patients younger than 46 years with an HLA-identical sibling donor were assigned to undergo allogeneic (allo) stem cell transplantation (SCT), and patients without such a donor were planned for autologous (auto) SCT. Between November 1993 and December 1999, of 1198 patients aged younger than 46 years, 822 achieved CR. The study group constituted 734 patients who received IC: 293 had a sibling donor and 441 did not. Allo-SCT and auto-SCT were performed in 68.9% and 55.8%, respectively. Cytogenetic determination was successfully performed in 446 patients. Risk groups were good (t(8;21), inv16), intermediate (NN or -Y only), and bad/very bad (all others). Median follow-up was 4 years; 289 patients relapsed, 66 died in CR1, and 293 died. Intention-to-treat analysis revealed that the 4-year disease-free survival (DFS) rate of patients with a donor versus those without a donor was 52.2% versus 42.2%, P =.044; hazard ratio = 0.80, 95% confidence interval (0.64, 0.995), the relapse incidence was 30.4% versus 52.5%, death in CR1 was 17.4% versus 5.3%, and the survival rate was 58.3% versus 50.8% (P =.18). The DFS rates in patients with and without a sibling donor were similar in patients with good/intermediate risk but were 43.4% and 18.4%, respectively, in patients with bad/very bad risk cytogenetics. In younger patients (15-35 years), the difference was more pronounced. The strategy to perform early allo-SCT led to better overall results than auto-SCT, especially for younger patients or those with bad/very bad risk cytogenetics.

Elevated serum vascular endothelial growth factor levels in patients with polycythemia vera and thrombotic complications.

Vascular endothelial growth factor (VEGF) induces platelet activation in a thrombin-dependent manner. We tested the serum VEGF levels in patients with polycythemia vera (PV) and found a significant correlation between increased VEGF and thrombosis. These findings suggest that high VEGF levels might contribute to the occurrence of thrombosis in this hematologic malignancy.