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SUMMARY Activated T lymphocytes often accumulate in the‘ower dermis of patients with systemic selerosis (seleroderma) any may play a role in the development of dermal libresis. We propagated and cloned these cells directly from skin biopsies in four of eight cases of early, antreated systemic selerosis with diffuse seleroderma. The cloning frequency estimates were f – 0.20 and f – 0.48 for T cells derived from the skin of two patients versus f - 0.68 and f - 0.96 for autologous blood T lymphocytes, All but one of 24 skin-derived selerederma clones were CD4+. Clonal analyses performed with CD4+ clones from patients and normal controls showed that all but one skin-derived clones synthesized either laterferon-gamma (60%), glycosantinolgycan-stimulatory factor (26%) or both (9%) when induced in vitro by a nitrogen, concanavalin A, but not by antologous dermal fibroblasts. In contrast, blood-derived clones had a different functional phenotype. All skin-derived clones produced tumour accrosis factor-alpha. Our results demonstrate that T lymphecytes obtained from the skin of patients with systemic selerois synthesized cytokoines which could modulale functions of human dermal fibroblasts.

Skeletal homeostasis relies upon a fine tuning of osteoclast (OCLs)-mediated bone resorption and osteoblast (OBLs)-dependent bone formation. This balance is unsettled by multiple myeloma (MM) cells, which impair OBL function and stimulate OCLs to generate lytic lesions. Emerging experimental evidence is disclosing a key regulatory role of microRNAs (miRNAs) in the regulation of bone homeostasis suggesting the miRNA network as potential novel target for the treatment of MM-related bone disease. Here, we report that miR-29b expression decreases progressively during human OCL differentiation in vitro. We found that lentiviral transduction of miR-29b into OCLs, even in the presence of MM cells, significantly impairs tartrate acid phosphatase (TRAcP) expression, lacunae generation and collagen degradation, which are relevant hallmarks of OCL activity. Accordingly, expression of cathepsin K and metalloproteinase 9 (MMP9) as well as actin ring rearrangement were impaired in the presence of miR-29b. Moreover, we found that canonical targets C-FOS and metalloproteinase 2 are suppressed by constitutive miR-29b expression which also downregulated the master OCL transcription factor, NAFTc-1. Overall, these data indicate that enforced expression of miR-29b impairs OCL differentiation and overcomes OCL activation triggered by MM cells, providing a rationale for miR-29b-based treatment of MM-related bone disease. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc.

Background Targeted therapy with BRAF and MEK inhibitors has improved the survival of patients with BRAF-mutated metastatic melanoma, but most patients relapse upon the onset of drug resistance induced by mechanisms including genetic and epigenetic events. Among the epigenetic alterations, microRNA perturbation is associated with the development of kinase inhibitor resistance. Here, we identified and studied the role of miR-146a-5p dysregulation in melanoma drug resistance. Methods The miR-146a-5p-regulated NFkB signaling network was identified in drug-resistant cell lines and melanoma tumor samples by expression profiling and knock-in and knock-out studies. A bioinformatic data analysis identified COX2 as a central gene regulated by miR-146a-5p and NFkB. The effects of miR-146a-5p/COX2 manipulation were studied in vitro in cell lines and with 3D cultures of treatment-resistant tumor explants from patients progressing during therapy. Results miR-146a-5p expression was inversely correlated with drug sensitivity and COX2 expression and was reduced in BRAF and MEK inhibitor-resistant melanoma cells and tissues. Forced miR-146a-5p expression reduced COX2 activity and significantly increased drug sensitivity by hampering prosurvival NFkB signaling, leading to reduced proliferation and enhanced apoptosis. Similar effects were obtained by inhibiting COX2 by celecoxib, a clinically approved COX2 inhibitor. Conclusions Deregulation of the miR-146a-5p/COX2 axis occurs in the development of melanoma resistance to targeted drugs in melanoma patients. This finding reveals novel targets for more effective combination treatment. Graphical Abstract

Posterior reversible encephalopathy cases are increasingly being reported in patients affected by COVID-19, but the largest series so far only includes 4 patients. We present a series of 6 patients diagnosed with PRES during COVID-19 hospitalized in 5 Centers in Lombardia, Italy. 5 out of the 6 patients required intensive care assistence and seizures developed at weaning from assisted ventilation. 3 out of 6 patients underwent cerebrospinal fluid analysis which was normal in all cases, with negative PCR for Sars-CoV-2 genome search. PRES occurrence may be less rare than supposed in COVID-19 patients and a high suspicion index is warranted for prompt diagnosis and treatment., Highlights • Posterior reversible encephalopathy syndrome is increasingly being reported in COVID-19 patients. • Weaning from assisted ventilation may be a critical moment in seizure development. • No evidence of viral genome in the cerebrospinal fluid in this cohort

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Erdheim-Chester disease (ECD) is a rare histiocytosis characterized by infiltration of multiple tissues by CD68+ foamy Mϕs (or ‘histiocytes’). Clinical manifestations arise from mass-forming lesions or from tissue and systemic inflammation. ECD histiocytes harbor oncogenic mutations along the MAPK-kinase signaling pathway (BRAFV600E in more than half of the patients), and secrete abundant pro-inflammatory cytokines and chemokines. Based on these features, ECD is considered an inflammatory myeloid neoplasm, and is accordingly managed with targeted kinase inhibitors or immunosuppressive and cytokine-blocking agents. Evidence is emerging that maladaptive metabolic changes, particularly up-regulated glycolysis, represent an additional, mutation-driven feature of ECD histiocytes, which sustains deregulated and protracted pro-inflammatory activation and cytokine production. Besides translational relevance to the management of ECD patients and to the development of new therapeutic approaches, recognition of ECD as a natural human model of chronic, maladaptive Mϕ activation instructs the understanding of Mϕ dysfunction in other chronic inflammatory conditions.

We present a laboratory-based prognostic calculator (designated CRO score) to risk stratify treatment-free survival in early stage (Rai 0) chronic lymphocytic leukemia developed using a training-validation model in a series of 1,879 cases from Italy, the United Kingdom and the United States. By means of regression analysis, we identified five prognostic variables with weighting as follows: deletion of the short arm of chromosome 17 and unmutated immunoglobulin heavy chain gene status, 2 points; deletion of the long arm of chromosome 11, trisomy of chromosome 12, and white blood cell count>32.0x103/microliter, 1 point. Low, intermediate and high-risk categories were established by recursive partitioning in a training cohort of 478 cases, and then validated in four independent cohorts of 144/395/540/322 cases, as well as in the composite validation cohort. Concordance indices were 0.75 in the training cohort and ranged from 0.63 to 0.74 in the four validation cohorts (0.69 in the composite validation cohort). These findings advocate potential application of our novel prognostic calculator to better stratify early-stage chronic lymphocytic leukemia, and aid case selection in risk-adapted treatment for early disease. Furthermore, they support immunocytogenetic analysis in Rai 0 chronic lymphocytic leukemia being performed at the time of diagnosis to aid prognosis and treatment, particularly in today's chemo-free era.

Multiple myeloma develops primarily inside the bone marrow microenvironment, that confers pro-survival signals and drug resistance. 3D cultures that reproduce multiple myeloma-bone marrow interactions are needed to fully investigate multiple myeloma pathogenesis and response to drugs. To this purpose, we exploited the 3D Rotary Cell Culture System bioreactor technology for myeloma-bone marrow co-cultures in gelatin scaffolds. The model was validated with myeloma cell lines that, as assessed by histochemical and electron-microscopic analyses, engaged contacts with stromal cells and endothelial cells. Consistently, pro-survival signaling and also cell adhesion-mediated drug resistance were significantly higher in 3D than in 2D parallel co-cultures. The contribution of the VLA-4/VCAM1 pathway to resistance to bortezomib was modeled by the use of VCAM1 transfectants. Soluble factor-mediated drug resistance could be also demonstrated in both 2D and 3D co-cultures. The system was then successfully applied to co-cultures of primary myeloma cells-primary myeloma bone marrow stromal cells from patients and endothelial cells, allowing the development of functional myeloma-stroma interactions and MM cell long-term survival. Significantly, genomic analysis performed in a high-risk myeloma patient demonstrated that culture in bioreactor paralleled the expansion of the clone that ultimately dominated in vivo. Finally, the impact of bortezomib on myeloma cells and on specialized functions of the microenvironment could be evaluated. Our findings indicate that 3D dynamic culture of reconstructed human multiple myeloma microenvironments in bioreactor may represent a useful platform for drug testing and for studying tumor-stroma molecular interactions.

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis, characterised by tissue infiltration by foamy CD68+ CD1a− histiocytes.1 The disease has pleomorphic clinical manifestations, including long bones and extraskeletal involvement, and may be life-threatening, particularly when heart and central nervous system are affected.1 ECD histiocytes secrete proinflammatory cytokines2 and carry activating mutations along the RAS-RAF-MEK-ERK protein kinase signalling pathway, most commonly the BRAFV600E oncogenic mutation.3 4 Accordingly, patients with ECD have been treated with cytokine inhibitors, including infliximab,1 ,5 and, more recently, with the BRAFV600E inhibitor vemurafenib.6 The latter, however, induces sustained but partial clinical responses and recurrences on discontinuation,6 underlining the need for more effective therapeutic strategies. To identify the outcomes downstream constitutive ERK phosphorylation in ECD histiocytes and their response to small molecule-based inhibition, we performed three-dimensional (3D) culture of tissues from three BRAFV600E-mutated ECD patients in the RCCS bioreactor7 (and online supplementary methods) in the presence/absence of vemurafenib or infliximab, used as control.### Supplementary data [annrheumdis-2018-214432supp001.pdf] All patient samples maintained production of prototypical cytokines and chemokines2 in bioreactor, thus validating this technology also for ECD; moreover, infliximab, and, to a lesser degree, vemurafenib, significantly decreased cyto-chemokines …

Purpose: Despite its indolent nature, chronic lymphocytic leukemia (CLL) remains an incurable disease. To establish the potential pathogenic role of miRNAs, the identification of deregulated miRNAs in CLL is crucial. Experimental Design: We analyzed the expression of 723 mature miRNAs in 217 early-stage CLL cases and in various different normal B-cell subpopulations from tonsils and peripheral blood. Results: Our analyses indicated that CLL cells exhibited a miRNA expression pattern that was most similar to the subsets of antigen-experienced and marginal zone–like B cells. These normal subpopulations were used as reference to identify differentially expressed miRNAs in comparison with CLL. Differences related to the expression of 25 miRNAs were found to be independent from IGHV mutation status or cytogenetic aberrations. These differences, confirmed in an independent validation set, led to a novel comprehensive description of miRNAs potentially involved in CLL. We also identified miRNAs whose expression was distinctive of cases with mutated versus unmutated IGHV genes or cases with 13q, 11q, and 17p deletions and trisomy 12. Finally, analysis of clinical data in relation to miRNA expression revealed that miR26a, miR532-3p, miR146-5p, and miR29c* were strongly associated with progression-free survival. Conclusion: This study provides novel information on miRNAs expressed by CLL and normal B-cell subtypes, with implication on the cell of origin of CLL. In addition, our findings indicate a number of deregulated miRNAs in CLL, which may play a pathogenic role and promote disease progression. Collectively, this information can be used for developing miRNA-based therapeutic strategies in CLL. Clin Cancer Res; 20(15); 4141–53. ©2014 AACR.

Hepatocyte growth factor, produced by stromal and follicular dendritic cells, and present at high concentrations in the sera of patients with chronic lymphocytic leukemia, prolongs the survival of leukemic B cells by interacting with their receptor, c-MET. It is, however, unknown whether hepatocyte growth factor influences microenvironmental cells, such as nurse-like cells, which deliver survival signals to the leukemic clone. We evaluated the expression of c-MET on nurse-like cells and monocytes from patients with chronic lymphocytic leukemia and searched for phenotypic/functional features supposed to be influenced by the hepatocyte growth factor/c-MET interaction. c-MET is expressed at high levels on nurse-like cells and at significantly higher levels than normal on monocytes from patients. Moreover, the hepatocyte growth factor/c-MET interaction activates STAT3(TYR705) phosphorylation in nurse-like cells. Indoleamine 2,3-dioxygenase, an enzyme modulating T-cell proliferation and induced on normal monocytes after hepatocyte growth factor treatment, was detected together with interleukin-10 on nurse-like cells, and on freshly-prepared patients' monocytes. Immunohistochemical/immunostaining analyses demonstrated the presence of c-MET(+) and indoleamine 2,3-dioxygenase(+) cells in lymph node biopsies, co-expressed with CD68 and vimentin. Furthermore nurse-like cells and chronic lymphocytic monocytes significantly inhibited T-cell proliferation, prevented by anti-transforming growth factor beta and interleukin-10 antibodies and indoleamine 2,3-dioxygenase inhibitors, and supported CD4(+)CD25(high+)/FOXP3(+) T regulatory cell expansion. We suggest that nurse-like cells display features of immunosuppressive type 2 macrophages: higher hepatocyte growth factor levels, produced by leukemic or other microenvironmental surrounding cells, may cooperate to induce M2 polarization. Hepatocyte growth factor may thus have a dual pathophysiological role: directly through enhancement of survival of the leukemic clone and indirectly by favoring T-cell immunosuppression.

In this paper, we describe the release of cyto-chemokines potentially relevant to Erdheim-Chester disease pathogenesis by intra-lesional cells from a patient with skeletal and multiorgan involvements.

The use of proteasome inhibitors have been a major advance in the treatment of multiple myeloma (MM), but their mechanisms of action remain largely unclear. A better understanding of the cellular events downstream of proteasome inhibition is essential to improve the response and identify new combination therapies for MM and other malignancies. This study analysed the relationships between redox homeostasis and bortezomib treatment in MM cells. Our data showed that decreasing intracellular glutathione through buthionine sulfoximine treatment strongly enhances bortezomib toxicity, whilst antioxidants protect MM cells from bortezomib-mediated cell death. Bortezomib treatment decreases intracellular glutathione both in MM cell lines and in malignant plasma cells obtained from MM patients. Glutamate-cysteine ligase (GCLM) and haem-oxygenase-1 (HMOX1), two genes involved in the Nrf-2-mediated antioxidant response, as well as two eIF2alpha-downstream transcription factors, activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP), are upregulated, indicating that redox-related adaptive responses are initiated in bortezomib-treated MM cells. These findings demonstrate tight links between sensitivity to proteasome inhibition and redox homeostasis in MM cells and have potential implications for treatment.

Background: The course of chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) partly depends on the mutational status of the variable region of immunoglobulin heavy chain genes (IgV H ), which defines two subgroups of tumours: mutated and unmutated. The expression of zeta-associated protein 70 (ZAP70) is significantly associated with the more aggressive unmutated forms. Aims: To assess the feasibility of the ZAP70 immunohistochemical test on bone-marrow biopsy (BMB) specimens and to compare the results with those of western blotting (WB) and IgV H mutational status assessed on neoplastic cells from peripheral blood. Methods: 26 patients with CLL/SLL detected on BMB and with known IgV H mutational status were selected. ZAP70 was determined by immunohistochemistry (IHC) comparing three antibodies from different sources (Upstate, Cell Signaling, Santa Cruz, California, USA) and two different methods (APAAP and EnVision + ). In 23 cases, ZAP70 WB results were also available. Results: ZAP70 determination on BMB specimens turned out to be easily feasible with routine procedures with reagents from Upstate and Cell Signaling. The results were concordant with those obtained with WB and mutational status analysis in >80% of the cases with both reagents. Three of four discordant cases were mutated/ZAP70 positive, with two staining weakly for ZAP70 on both WB and IHC. Conclusions: The study confirms the role of ZAP70 as a possible surrogate of mutational status and emphasises its application in routine diagnostics; it discloses a small subset of discordant cases (mutated/ZAP70 weakly positive) that clinically cluster with the more favourable forms.

Objectives Erdheim-Chester disease (ECD) is a rare form of histiocytosis characterised by uncontrolled chronic inflammation. The oncogenic BRAF V600E mutation has been reported in biopsies in 19 out of 37 patients with ECD from the largest published cohort, but never found in the patients’ peripheral blood. Also, the role of the mutation in the pathogenesis of the disease has not been elucidated yet. BRAF V600E has been associated with oncogene-induced senescence (OIS), a protective mechanism against oncogenic events, characterised by the induction of proinflammatory pathways. Methods We verified the BRAF status in biopsies and peripheral blood from 18 patients with ECD from our cohort and matched controls by means of immunohistochemistry and of an ultrasensitive assay, based on the combination of a locked nucleic acid PCR and pyrosequencing. Droplet digital PCR was used to confirm the findings. We also evaluated the presence of senescence markers in ECD histiocytes. Results BRAF V600E mutation was present in all the biopsy and peripheral blood samples from patients with ECD and in none of the controls. ECD histiocytes and a fraction of circulating monocytes from patients with ECD showed signs of a constitutive activation of the MAPK pathway. Moreover, BRAF-mutated histiocytes expressed markers of OIS. Conclusions The oncogenic BRAF V600E mutation is present in biopsies and in the peripheral blood from all patients with ECD who were evaluated and is associated with OIS. These findings have significant implications for the pathogenesis, diagnosis and treatment of ECD.

Angiopoietin-2 (Ang-2) is involved in angiogenesis in both solid and hematological malignancies. In Multiple Myeloma (MM), serum Ang-2 correlates with disease progression and response to therapy. To address the patho-physiologic role of Ang-2 in MM associated angiogenesis, we used sera from patients with active MM, which contained significantly higher levels of the molecule, compared to those from patients with smoldering MM and Monoclonal Gammopathy of Undetermined Significance. MM Bone Marrow (BM) sera with high Ang-2 concentration specifically contributed to endothelial cell (EC) activation, while Ang-1 containing sera maintained EC stabilization. The functional dichotomy of Ang-1 and Ang-2 was confirmed by the triggering of distinctive signaling pathways down-stream the common Tie-2 receptor, i.e., the Akt or the ERK- phosphorylation pathway. Notably, Ang-2 but not VEGF serum levels correlated with BM micro-vessel density, further underscoring the key role of Ang-2 in angiogenesis. Western Blot, RT-PCR and immunocytochemistry identified MMEC as the major source of Ang-2, at variance with MM cells and CD14(+) BM monocytes. These data suggest that Ang-2 produced in the BM milieu may contribute to MM angiogenesis and suggest that the molecule can be further exploited both as angiogenesis biomarker and as a potential therapeutic target. (C) 2014 Elsevier Inc. All rights reserved.

We have previously shown that VEGF165 gene delivery into ischemic skeletal muscle exerts not only proangiogenic, but also remarkable antiapoptotic and proregenerative activity. The aim of this study was to determine whether recombinant adeno-associated virus (rAAV)-mediated gene delivery of VEGF165 into cardiac muscle, during acute myocardial infarction, exerts a protective effect to promote long-term functional recovery. Acute infarction of the anterior LV wall was induced in 12 chronically instrumented dogs by permanent occlusion of the LAD coronary artery. Four hours after occlusion, rAAV-VEGF165 or rAAV-LacZ (n=6 each; 5×10 12 viral particles per animal) was directly injected with an echo-guided needle into the dysfunctional cardiac wall. LV and arterial pressure, dP/dt max , and ejection fraction were not significantly different between the two groups over time. In contrast, in the infarcted region, at four weeks after infarction, fractional shortening was 75±18% and −3±15% of baseline and length-pressure area was 54±15% and 0.8±15% of baseline in VEGF165 versus LacZ, respectively ( P P

We describe an immunocompetent 61-year-old woman who was negative for human immunodeficiency virus and who had recurrent human herpesvirus 8 (HHV-8) infection associated with a relapsing systemic inflammatory syndrome characterized by fever, lymphadenopathy, splenomegaly, edema, arthrosynovitis, and rash. Kaposi's sarcoma developed 10 months after the initial clinical presentation. A correlation was documented between the recurrent clinical manifestations and the HHV-8 load in plasma and peripheral-blood mononuclear cells. Histologic examination of an enlarged lymph node heavily infected with HHV-8 revealed an atypical lymphoproliferative disorder characterized by paracortical hyperplasia and collapsed primary and secondary follicles.

Familial amyloidotic polyneuropathy is a rare autosomal dominant disease, with clinical symptoms beginning in most kindreds within the third to seventh decades of life. The primary defect results from one of a number of mutations in the transthyretin (TTR) gene. Over 80 mutations in the TTR gene have been described. Most mutations give rise to adult onset progressive peripheral and autonomic neuropathy, due to amyloid deposition within the nerves, and often subclinical cardiac amyloid and vitreous deposits. We report here the clinical and molecular characterization of a rare TTR missense mutation discovered in a young woman from Macedonia, showing severe axonal sensory-motor polyneuropathy, restrictive cardiomyopathy and bilateral vitreous deposits. The transthyretin gene, analyzed by direct nucleotide sequencing, demonstrated a T to G transversion at nucleotide 183 in the exon 2 which is predicted to cause a heterozygous valine for phenylalanine substitution at codon 33 (TTR Phe33Val). This mutation has been previously reported only twice, without complete clinical descriptions.

Erdheim-Chester disease (ECD) is a rare, non-Langerhans histiocytosis. Recent findings suggest that ECD is a clonal disorder, marked by recurrent BRAFV600E mutations in >50% of patients, in which chronic uncontrolled inflammation is an important mediator of disease pathogenesis. Although ∼500 to 550 cases have been described in the literature to date, increased physician awareness has driven a dramatic increase in ECD diagnoses over the last decade. ECD frequently involves multiple organ systems and has historically lacked effective therapies. Given the protean clinical manifestations and the lack of a consensus-derived approach for the management of ECD, we provide here the first multidisciplinary consensus guidelines for the clinical management of ECD. These recommendations were outlined at the First International Medical Symposium for ECD, comprised of a comprehensive group of international academicians with expertise in the pathophysiology and therapy of ECD. Detailed recommendations on the initial clinical, laboratory, and radiographic assessment of ECD patients are presented in addition to treatment recommendations based on critical appraisal of the literature and clinical experience. These formalized consensus descriptions will hopefully facilitate ongoing and future research efforts in this disorder.

Fas and Fas ligand (FasL) have been found both in lymphoid and in non-lymphoid malignancies, and are thought to play a role in the interplay between tumors and the immune system. Here we investigated Fas/FasL expression, function and intracellular signalling pathways in human melanomas. Of 5 melanoma cell lines, 3 expressed Fas at their surface, and all of them expressed FasL. FasL was functional, since it triggered Fas-induced apoptosis of human T lymphocytes clones. Conversely, cross-linking of Fas molecule with a specific monoclonal antibody failed to induce apoptosis in any of the melanomas tested, or ceramide intracellular accumulation or caspase-3 activation, pointing to an early alteration in the Fas-triggered signaling cascade. All melanomas retained the ability to undergo apoptosis induced by cytotoxic lymphocytes, which was mediated by the granule exocytosis mechanism. This suggests that melanoma cells evade immune-mediated Fas-triggered apoptosis via a selective blockade of the Fas apoptotic pathway. Cytotoxic lymphocytes, however, may circumvent tumor resistance to Fas-induced death via granzyme-mediated apoptosis, further supporting the development of immunotherapeutic strategies in the treatment of cancer.

Three-dimensional (3-D) culture models are emerging as invaluable tools in tumor biology, since they reproduce tissue-specific structural features and cell-cell interactions more accurately than conventional 2-D cultures. Multiple Myeloma, which depends on myeloma cell-Bone Marrow microenvironment interactions for development and response to drugs, may particularly benefit from such an approach. An innovative 3-D dynamic culture model based on the use of the RCCS™ Bioreactor was developed to allow long-term culture of myeloma tissue explants. This model was first validated with normal and pathological explants, then applied to tissues from myeloma patients. In all cases, histological examination demonstrated maintenance of viable myeloma cells inside their native microenvironment, with an overall well preserved histo-architecture including bone lamellae and vessels. This system was then successfully applied to evaluate the cytotoxic effects exerted by the proteasome inhibitor Bortezomib not only on myeloma cells but also on angiogenic vessels. Moreover, as surrogate markers of specialized functions expressed by myeloma cells and microenvironment, β2 microglobulin, VEGF and Angiopoietin-2 levels, as well as Matrix Metalloproteases activity, were evaluated in supernatants from 3D cultures and their levels reflected the effects of Bortezomib treatment. Notably, determination of β2 microglobulin levels in supernatants from Bortezomib-treated samples and in patients'sera following Bortezomib-based therapies disclosed an overall concordance in the response to the drug ex vivo and in vivo. Our findings indicate, as a proof of principle, that 3-D, RCCS™ bioreactor-based culture of tissue explants can be exploited for studying myeloma biology and for a pre-clinical approach to patient-targeted therapy.

Purpose: Deregulated expression of miRNAs has been shown in multiple myeloma (MM). A promising strategy to achieve a therapeutic effect by targeting the miRNA regulatory network is to enforce the expression of miRNAs that act as tumor suppressor genes, such as miR-34a. Experimental Design: Here, we investigated the therapeutic potential of synthetic miR-34a against human MM cells in vitro and in vivo. Results: Either transient expression of miR-34a synthetic mimics or lentivirus-based miR-34a-stable enforced expression triggered growth inhibition and apoptosis in MM cells in vitro. Synthetic miR-34a downregulated canonic targets BCL2, CDK6, and NOTCH1 at both the mRNA and protein level. Lentiviral vector-transduced MM xenografts with constitutive miR-34a expression showed high growth inhibition in severe combined immunodeficient (SCID) mice. The anti-MM activity of lipidic-formulated miR-34a was further shown in vivo in two different experimental settings: (i) SCID mice bearing nontransduced MM xenografts; and (ii) SCID-synth-hu mice implanted with synthetic 3-dimensional scaffolds reconstituted with human bone marrow stromal cells and then engrafted with human MM cells. Relevant tumor growth inhibition and survival improvement were observed in mice bearing TP53-mutated MM xenografts treated with miR-34a mimics in the absence of systemic toxicity. Conclusions: Our findings provide a proof-of-principle that formulated synthetic miR-34a has therapeutic activity in preclinical models and support a framework for development of miR-34a–based treatment strategies in MM patients. Clin Cancer Res; 18(22); 6260–70. ©2012 AACR.

MicroRNAs (miRNAs) with tumor-suppressor potential might have therapeutic applications in multiple myeloma (MM) through the modulation of still undiscovered molecular pathways. Here, we investigated the effects of enforced expression of miR-29b on the apoptotic occurrence in MM and highlighted its role in the context of a new transcriptional loop that is finely tuned by the proteasome inhibitor bortezomib. In details, in vitro growth inhibition and apoptosis of MM cells was induced by either transient expression of synthetic miR-29b or its stable lentivirus-enforced expression. We identified Sp1, a transcription factor endowed with oncogenic activity, as a negative regulator of miR-29b expression in MM cells. Since Sp1 expression and functions are regulated via the 26S proteasome, we investigated the effects of bortezomib on miR-29b-Sp1 loop, showing that miR-29b levels were indeed upregulated by the drug. At the same time, the bortezomib/miR-29b combination produced significant pro-apoptotic effects. We also demonstrated that the PI3K/AKT pathway plays a major role in the regulation of miR-29b-Sp1 loop and induction of apoptosis in MM cells. Finally, MM xenografts constitutively expressing miR-29b showed significant reduction of their tumorigenic potential. Our findings indicate that miR-29b is involved in a regulatory loop amenable of pharmacologic intervention and modulates the anti-MM activity of bortezomib in MM cells.

Identification of patients at risk of early disease progression is the mainstay of tailored management in chronic lymphocytic leukemia (CLL). Although application of established biomarkers is limited by intrinsic detection/readout complexities, abnormality of κ and λ serum-free light chain ratio [sFLC (κ/λ)] was proposed as a straightforward prognosticator in CLL. By analyzing 449 therapy-naive patients, we show that an abnormal sFLC(κ/λ), along with CD38, ZAP-70, IGHV mutations, cytogenetics and stage, independently predicts treatment-free survival (TFS) but becomes prognostically irrelevant if the cumulative amount of clonal and nonclonal FLCs [sFLC(κ + λ)], a variable associated with cytogenetic risk, exceeds the threshold of 60.6 mg/mL. Patients with sFLC(κ + λ) above cut-off displayed a poorer TFS outcome, irrespective of sFLC(κ/λ). Only ZAP-70, cytogenetics, stage, and TFS remained associated with sFLC(κ + λ) in a multivariate model. By assigning 1 point each for these variables, the 3-year probability of TFS was 94.8%, 84.5%, 61.6%, and 21.1% for patients scoring 0, 1, 2, and 3 + 4, respectively (P < .0001). These data, and the demonstration that monoclonal and polyclonal B cells concur to FLC synthesis in tumor tissues, suggest that sFLC(κ/λ) and sFLC(κ + λ) mirror distinct biologic processes in CLL. sFLC(κ + λ) assessment represents a sensitive and cost-effective tool for identifying CLL patients requiring early treatment.

Here we describe clinical, neuropsychological and neuroradiological findings in 6 subjects belonging to two unrelated Italian cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) kindreds from the same geographic area who shared a common Arg1006Cys mutation. Subjects from Family A were virtually asymptomatic, and yet showed MRI pathological findings and a cluster of sub-clinical neuropsychological defects mainly centred on the visuospatial domain; patients from Family B had presented several clinically relevant episodes and showed a general cognitive impairment compatible with the clinical picture of vascular dementia. The present clinical observations are consistent with the hypothesis of a geographical clustering for CADASIL, and highlight that sub-clinical cognitive impairment may help to identify this syndrome in families presenting with only migraine.

A reciprocal influence exists between mycobacteria and HIV: HIV-infected individuals are more susceptible to mycobacterial infections and, on the other hand, mycobacterial infection results inacceleration of HIV disease progression. Vgamma9/Vdelta2 T lymphocytes are known to participate in the defense against intracellular pathogens, including Mycobacterium tuberculosis. Indeed, they kill mycobacteria-infected macrophages and, upon recognition of mycobacterial Ag, release TNF-alpha and IFN-gamma, which are also up-regulators of HIV expression. To assess whether mycobacteria-activated gamma delta T lymphocytes contribute to the enhancement of HIV replication, we established an in vitro model mimicking HIV and mycobacteria co-infection with the latently HIV-infected promonocytic U1 cell line and Vgamma9/Vdelta2 peripheral lymphocytes stimulated with mycobacterial Ag. gamma delta T cell activation determined two distinct, but connected effects, namely U1cell death and HIV expression. Both effects were mainly mediated by release of TNF-alpha and IFN-gamma from activated gamma delta lymphocytes, although Fas-FasL interaction also contributed to U1 apoptosis. The final outcome on U1 survival, and thus, on HIV expression, highly depended on mycobacterial Ag concentration coupled to the differential secretory potency of gamma delta cells. In particular, the induction of viral expression prevailed at low Ag concentration and with lower cytokine production by mycobacteria-activated gamma delta cells. Notably, during the course of HIV infection, Vgamma9/Vdelta2 lymphocytes are reported to be functionally impaired and may thus indirectly influence the progression of HIV disease. In addition, a predominant inhibition of viral replication was encountered when mycobacteria-activated gamma delta T cells were co-cultured with primary HIV-infected macrophages. Thus, we suggest that specific recognition of mycobacterial Ag by gamma delta T lymphocytes in co-infected individuals may modulate viral replication through the complex array of soluble factors released.

We studied whether signaling through CD30, a member of the TNF receptor family, affected acute infection with HIV-1, encompassing its entire replicative cycle. Several non-Hodgkin cell lines, targets of CXCR4-dependent (X4) HIV-1 infection, were positive for CD30 expression. CD30 ligation induced up-regulation of viral replication only in certain CD30(+) cell lines. Enhancement of X4 virus replication by CD30 engagement inversely correlated with both CD30 surface density and constitutive NF-kappaB activation. Conversely, expression of CD30, but not of other members of the TNF receptor family, was proportional to constitutive NF-kappaB binding. Concomitantly, secretion of soluble (s) CD30 increased in all cell lines by CD30 ligation. sCD30 release was enhanced by engagement of CD30 alone and, to a greater extent, by co-engagement of CD3 also in primary gammadelta T lymphocytes, along with complementary modulations of their surface CD30 expression. sCD30-containing supernatant specifically inhibited HIV-1 expression induced by CD30 engagement in chronically infected ACH-2 T cells; thus sCD30 may act as a negative feed-back molecule. In conclusion, we have delineated novel features of CD30 biology and underline the peculiar link of CD30 expression to constitutive NF-kappaB activation which is pivotal to both HIV replication and cell survival.

Heat shock proteins (hsp) are a family of proteins characteristically produced under stress conditions in normal cells. Overexpression of hsp 70 kDa protects tumoral cells from tumor necrosis factor cytotoxicity and is related to drug resistance. In this study we investigated whether hsp are abnormally expressed in melanoma cells in vivo. Antibodies directed against hsp 72 and hsp 90 were used to identify hsp on non-stressed neoplastic cells derived from surgical specimens of two primary and four metastatic melanomas. Hsp 72 and hsp 90 were always present at high level in the cytoplasm of melanoma cells. It is possible that the activation of hsp genes during neoplastic transformation confers a selective advantage to tumoral cells in vivo, allowing them to escape the immunological surveillance.

The sensitivities and predictive values of visual, somatosensory, and brain auditory evoked potentials (EPs), cerebrospinal fluid oligoclonal banding (CSF-OB) and magnetic resonance imaging (MRI) were evaluated for the early diagnosis of clinically definite multiple sclerosis (CDMS). Paraclinical evidence of asymptomatic lesions allows a diagnosis of CDMS. Eighty-two patients in whom MS was suspected but diagnosis of CDMS was not possible entered the study prospectively. Paraclinical examinations were performed at entry. Patients were examined and underwent EPs every 6 months, and MRI yearly. After a mean follow-up of 2.9 years, 28 patients (34%) had developed CDMS (McDonald-Halliday criteria). The initial MRI was strongly suggestive of MS in 19 of these (68%), while 27 (96%) had at least one MS-like abnormality in the initial MRI. CSF-OB and EPs had lower sensitivities. CDMS developed during follow-up in 19 of the 36 patients (53%) who had an initial MRI strongly suggestive of MS but in only 1 of the 25 who had normal MRI when first studied. These results support previous conclusions that MRI is the most sensitive test for detecting white matter asymptomatic lesions, and the most predictive for the diagnosis of CDMS.

Abnormalities of T-cell subsets in patients with multiple sclerosis are well known; in order to assess whether immunological abnormalities are relevant in the pathogenesis of the disease after its clinical onset, peripheral blood lymphocyte subsets (CD3+, CD4+, CD4(+)-CD45RA+, CD4+CD45RA-, CD8+, CD8+CD57+, CD57+, CD25+) were analysed serially in 25 patients at the first clinical episode suggestive of inflammatory demyelinating disease and in an equal number of age- and sex-matched controls. During the follow-up period (12-18 months, mean 14) 6 of 25 patients presented new relapses: in this subgroup of patients, significant changes in CD4+ ratio (% CD4+CD45RA-/%CD4+CD45RA+) were detected in comparison both with healthy controls and with clinically stable patients. Patients clinically stable at follow-up did not display immunological abnormalities, regardless of the presence or absence of cerebrospinal fluid and/or magnetic resonance imaging alterations consistent with multiple sclerosis. These findings suggest a possible prognostic role of early T-cell subset imbalance in multiple sclerosis.

Blymphocytes undergo during their development several sequential rearrangements at the immunoglobulin (Ig) loci (1). The first event is a D-JH recombination that usually takes place at both the heavy chain (IgH) loci, and is then followed by rearrangement of one of the numerous VHgenes to the DJHcomplex (2). When a functional VDJ rearrangement has taken place, synthesis of μ Polypeptide ensues and rearragments of the light chain loci begin. A K-λ hyerarchy has been demonstrated in both human and mouse B cells (3,4). A successful heavy chain gene recombination stops any further rearrangement at the IgH locus (5,6), and possibly stimulates IgL recombination. Similarly the creation of a productive light chain gene blocks further recombinations at the IgL loci (5). Subsequently IgM molecules are synthetized and expressed on the cell surface by lymphocytes (7). The latter may coexpress IgD through alternative splicing of the VDJ - Cμ -C δ transcription unit (8). IgM+ B cell may undergo a second recombinatorial event at the IgH locus, termed isotype switching. This event generally implies the deletion of Cμ, Cδ and all the CHgenes which are located 5′ to the one CH gene that will be expressed (9,10). Although the sequences mediating switch recombination have been isolated and determined (9–11), rather little is known about the mechanisms regulating isotype switching. The question of how an IgM+B lymphocyte decides which CH gene to recombine is still open. It is well known that certain antigens or routes of immunization result in vivo in the predominance of a given isotype (12). On the other hand several in vitro experiments have shown that more than one isotype can be produced by the progeny of a single B cell (13–15). Isotype switching is not the only differentiative option of an IgM+ B cell. The latter may infact respond to antigen or mitogen by differentiating into IgM secreting plasmacells (7). It is generally accepted that plasmacell may undergo a very limited number of divisions.

A patient with a B-cell chronic lymphocytic leukemia, whose lymphocytes also formed rosettes with sheep red cells, is described. The B-cell nature of the malignant lymphocytes was determined by surface marker analysis, and cytochemical and ultrastructural studies. The lymphocyte membrane immunoglobulin (IgG1K) did not have anti-sheep red cell activity and was not responsible for the binding of sheep erythrocytes to the leukemic cells as shown by (i) the failure to inhibit rosette formation with anti-immunoglobulin reagents and (ii) the different sensitivity to proteolysis of the membrane immunoglobulin and the sheep erythrocyte receptor. The malignant lymphocytes expressed a receptor for sheep erythrocytes similar to that of normal T cells since they stained with monoclonal antibodies directed against the sheep red cell receptors. Furthermore these antibodies blocked rosette formation. Endogenous labeling experiments demonstrated that the patient's cells produced IgG both of the membrane and of the secretory type. The latter molecular form was also actively secreted. Ultrastructural studies demonstrated that the malignant clone comprised cells at different maturational stages and with different secretory properties. These findings were confirmed by the analysis of intracytoplasmic acid hydrolases, which are normally expressed at late maturational stages. These data are consistent with the hypothesis that a process of maturation was occurring within the malignant clone.

131I-labeled IgD-like molecules extracted from the membrane of mouse spleen, and lymph node cells and their constitutive chains have been characterized by sodium dodecyl sulfate polyacrylamide slab gel electrophoresis (SDS-PAGE) followed by radioautography. Unreduced mouse IgD-like molecules concentrated in two definite bands (IgD1 and IgD2). IgD, migrated slightly ahead of 131I-labeled mouse membrane IgM and displayed a mobility very similar to that of 131I-labeled IgD extracted from the membrane of human tonsil cells. IgD2 migrated faster than both IgD1 and human membrane IgD (mIgD), but slower than 14C-labeled mouse IgG2 b used as marker. The different mobility of IgD1 and IgD2 was due to difference in size of their respective H-chains (δ1 and δ2), as shown by SDS-PAGE analysis of the two molecules after reduction. Mol.wt. determination of IgD1, IgD2 and of the corresponding constitutive chains are consistent with an H2L2 structure. IgD1 and IgD2 were partially replaced following prolonged dialysis by molecules with a SDS-PAGE mobility consistent with an HL structure, IgD3. In contrast to that found for spleen and lymph node, IgD1 only was detected on the surface of bone marrow cells. Immunofluorescence experiments have shown that while the majority of mouse lymph node or spleen cells bear IgM and IgD, IgM was found to be the predominant Ig class on the surface of bone marrow cells, although a certain number of IgD-IgM and a few IgD-positive cells were found. Experiments where mouse lymphocytes have been treated with pronase have indicated that, in analogy with mlgD of primates, mouse IgD-like molecules are very labile and can be removed from the cell surface by very mild proteolytic treatment.