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Simple Summary Osteolytic bone lesions represent an important clinical feature of multiple myeloma (MM). MM cells metabolize very high amounts of glutamine (Gln) and significantly lower Gln in the bone marrow. In this contribution we demonstrate that MM-dependent Gln depletion impairs the differentiation of bone marrow mesenchymal stromal cells into osteoblasts, the cells that form new bone tissue. We also found that osteoblast differentiation is associated with increased expression of glutaminase, the main enzyme that metabolizes Gln, SNAT2, a transporter able to accumulate Gln into the cells, and asparagine synthetase, the enzyme that uses Gln to obtain asparagine (Asn). Asn rescued osteoblast differentiation of Gln-starved mesenchymal stromal cells. These results demonstrate that MM cells impair osteoblast differentiation, hindering mesenchymal Asn synthesis through Gln depletion. Besides providing a metabolic mechanism underlying osteolytic lesions in MM, these results suggest that Asn supplementation may prevent bone disease in MM patients. Abstract Multiple myeloma (MM) cells consume huge amounts of glutamine and, as a consequence, the amino acid concentration is lower-than-normal in the bone marrow (BM) of MM patients. Here we show that MM-dependent glutamine depletion induces glutamine synthetase in stromal cells, as demonstrated in BM biopsies of MM patients, and reproduced in vitro by co-culturing human mesenchymal stromal cells (MSCs) with MM cells. Moreover, glutamine depletion hinders osteoblast differentiation of MSCs, which is also severely blunted by the spent, low-glutamine medium of MM cells, and rescued by glutamine restitution. Glutaminase and the concentrative glutamine transporter SNAT2 are induced during osteoblastogenesis in vivo and in vitro, and both needed for MSCs differentiation, pointing to enhanced the requirement for the amino acid. Osteoblastogenesis also triggers the induction of glutamine-dependent asparagine synthetase (ASNS), and, among non-essential amino acids, asparagine rescues differentiation of glutamine-starved MSCs, by restoring the transcriptional profiles of differentiating MSCs altered by glutamine starvation. Thus, reduced asparagine availability provides a mechanistic link between MM-dependent Gln depletion in BM and impairment of osteoblast differentiation. Inhibition of Gln metabolism in MM cells and supplementation of asparagine to stromal cells may, therefore, constitute novel approaches to prevent osteolytic lesions in MM.

// Federica Costa 1, * , Denise Toscani 1, * , Antonella Chillemi 2 , Valeria Quarona 2 , Marina Bolzoni 1 , Valentina Marchica 1, 6 , Rosanna Vescovini 3 , Cristina Mancini 4 , Eugenia Martella 4 , Nicoletta Campanini 4 , Chiara Schifano 5 , Sabrina Bonomini 5 , Fabrizio Accardi 1, 5 , Alberto L. Horenstein 2 , Franco Aversa 1, 5 , Fabio Malavasi 2 and Nicola Giuliani 1, 5, 6 1 Department of Medicine and Surgery, University of Parma, Parma, Italy 2 Laboratory of Immunogenetics, Department of Medical Sciences and CeRMS, University of Torino, Torino, Italy 3 Clinical Medicine Unit, Department of Medicine and Surgery, University of Parma, Parma, Italy 4 Pathology, “Azienda Ospedaliero-Universitaria di Parma”, Parma, Italy 5 Hematology and BMT Center, “Azienda Ospedaliero-Universitaria di Parma”, Parma, Italy 6 CoreLab, “Azienda Ospedaliero-Universitaria di Parma”, Parma, Italy * These authors contributed equally to this work Correspondence to: Nicola Giuliani, email: nicola.giuliani@unipr.it Keywords: multiple myeloma, CD38, osteoclast, bone disease, immunotherapy Received: October 27, 2016 Accepted: April 29, 2017 Published: May 16, 2017 ABSTRACT It is known that multiple myeloma (MM) cells express CD38 and that a recently developed human anti-CD38 monoclonal antibody Daratumumab mediates myeloma killing. However, the expression of CD38 and other functionally related ectoenzymes within the MM bone niche and the potential effects of Daratumumab on bone cells are still unknown. This study firstly defines by flow cytometry and immunohistochemistry the expression of CD38 by bone marrow cells in a cohort of patients with MM and indolent monoclonal gammopathies. Results indicate that only plasma cells expressed CD38 at high level within the bone niche. In addition, the flow cytometry analysis shows that CD38 was also expressed by monocytes and early osteoclast progenitors but not by osteoblasts and mature osteoclasts. Indeed, CD38 was lost during in vitro osteoclastogenesis. Consistently, we found that Daratumumab reacted with CD38 expressed on monocytes and its binding inhibited in vitro osteoclastogenesis and bone resorption activity from bone marrow total mononuclear cells of MM patients, targeting early osteoclast progenitors. The inhibitory effect was not observed from purified CD14 + cells, suggesting an indirect inhibitory effect of Daratumumab. Interestingly, all-trans retinoic acid treatment increased the inhibitory effect of Daratumumab on osteoclast formation. These observations provide a rationale for the use of an anti-CD38 antibody-based approach as treatment for multiple myeloma-induced osteoclastogenesis.

Periductal stromal tumor (PDST) is a rare biphasic tumor of the breast that exhibits low-grade malignancy and intermediate behavior. It is characterized by proliferation of atypical spindle cells surrounding benign mammary ducts and infiltrating adjacent adipose tissue. PDST is distinguished from phyllodes tumor by its lack of leaf-like architecture; however, it is still unclear whether PDST is a separate entity or a certain spectrum of phyllodes tumor. Phyllodes tumors constitute a group of rare epithelial lesions of the breast which mainly develops at around 40-50 years. The histologic characteristics to be considered are many and often heterogeneous in the same lesion which makes interpretation in needle biopsy material difficult. Most phyllodes tumors have a benign nature, with a high rate of postsurgical recurrence. In the malignant form, metastases are described by distant hematogenous route; its indolent behavior implies a tight surgical management with precise excision of the lesion even if there is not, however, a unanimous consent on the parameters of accuracy of the margins.

Primary neuroendocrine carcinoma of the breast (NECB) is one of the rarest subtypes of breast tumor, and for this reason, there are no data from prospective clinical trials on its optimal management. Its incidence is

The skin is a possible site of extramedullary localization in multiple myeloma (MM) patients; however, the mechanisms involved in this process are poorly understood. We describe the case of a refractory MM patient who developed a cutaneous localization under bortezomib treatment and we further expanded observations in other eight MM patients. We focused on the expression of genes involved in plasma cell skin homing, including CCR10, which was highly expressed. Moreover, we observed a lack of CXCR4 surface expression and the down-regulation of ICAM1/CD54 throughout the progression of the disease, suggesting a possible mechanism driving the escape of MM cells from the bone marrow into the skin.

The importance of glutamine (Gln) metabolism in multiple myeloma (MM) cells and its potential role as a therapeutic target are still unknown, although it has been reported that human myeloma cell lines (HMCLs) are highly sensitive to Gln depletion. In this study, we found that both HMCLs and primary bone marrow (BM) CD138(+) cells produced large amounts of ammonium in the presence of Gln. MM patients have lower BM plasma Gln with higher ammonium and glutamate than patients with indolent monoclonal gammopathies. Interestingly, HMCLs expressed glutaminase (GLS1) and were sensitive to its inhibition, whereas they exhibited negligible expression of glutamine synthetase (GS). High GLS1 and low GS expression were also observed in primary CD138(+) cells. Gln-free incubation or treatment with the glutaminolytic enzyme l-asparaginase depleted the cell contents of Gln, glutamate, and the anaplerotic substrate 2-oxoglutarate, inhibiting MM cell growth. Consistent with the dependence of MM cells on extracellular Gln, a gene expression profile analysis, on both proprietary and published datasets, showed an increased expression of the Gln transporters SNAT1, ASCT2, and LAT1 by CD138(+) cells across the progression of monoclonal gammopathies. Among these transporters, only ASCT2 inhibition in HMCLs caused a marked decrease in Gln uptake and a significant fall in cell growth. Consistently, stable ASCT2 downregulation by a lentiviral approach inhibited HMCL growth in vitro and in a murine model. In conclusion, MM cells strictly depend on extracellular Gln and show features of Gln addiction. Therefore, the inhibition of Gln uptake is a new attractive therapeutic strategy for MM.

C-X3-C motif chemokine ligand 1 (CX3CL1)/fractalkine is a chemokine released after cleavage by two metalloproteases, ADAM metallopeptidase domain 10 (ADAM10) and ADAM metallopeptidase domain 17 (ADAM17), involved in inflammation and angiogenesis in the cancer microenvironment. The role of the CX3CL1/ C-X3-C motif chemokine receptor 1(CX3CR1) axis in the multiple myeloma (MM) microenvironment is still unknown. Firstly, we analyzed bone marrow (BM) plasma levels of CX3CL1 in 111 patients with plasma cell disorders including 70 with active MM, 25 with smoldering myeloma (SMM), and 16 with monoclonal gammopathy of undetermined significance (MGUS). We found that BM CX3CL1 levels were significantly increased in MM patients compared to SMM and MGUS and correlated with BM microvessel density. Secondly, we explored the source of CX3CL1 in MM and BM microenvironment cells. Primary CD138+ cells did not express CXC3L1 but up-regulated its production by endothelial cells (ECs) through the involvement of tumor necrosis factor alpha (TNF&alpha, ). Lastly, we demonstrated the presence of CX3CR1 on BM CD14+CD16+ monocytes of MM patients and on ECs, but not on MM cells. The role of CX3CL1 in MM-induced angiogenesis was finally demonstrated in both in vivo chick embryo chorioallantoic membrane and in vitro angiogenesis assays. Our data indicate that CX3CL1, present at a high level in the BM of MM patients, is a new player of the MM microenvironment involved in MM-induced angiogenesis.

Background The etiology of traumatic ulcerative granulomas with stromal eosinophilia (TUGSE) is not clear, traumatic irritation having advocated as the most likely cause. TUGSEs are typically self-limiting slow-healing lesions of the oral mucosa with unclear pathogenesis, commonly manifesting as a rapidly developing, long-lasting ulcer. Case presentation Here we report a controversial case of a self-healing lesion of the tongue in a 57 year-old woman. A clonal T-cell proliferation and CD30 negative immunohistochemical (IHC) profile could be documented. Discussion and conclusion In view of the very peculiar clinical and histological features, a retrospective diagnosis of a TUGSE with scarce eosinophilic infiltrate (possibly in regression), displaying CD30- T-clonal proliferation was eventually rendered. The patient did not report signs of recurrence after a 3-year follow-up period.

The association between Neurofibromatosis type I (NF1) and multiple myeloma (MM), a plasma cell, dyscrasia is very rare. Here we put to the attention of the scientific community two new cases. The first one is a patient with active MM whereas the second with smoldering MM. Both patients present typical features of NF1 but skeletal alterations were present only in the second case including dysplasia, marked scoliosis and osteoporosis. MM osteolytic lesions were absent in both patients. In addition to the clinical diagnosis of NF1, a molecular testing for NF1 gene mutations has been performed finding that patient one was heterozygous for the c.6855C>A (Tyr2285Ter) mutation, whilepatient two was heterozygous for thec.7838dupC (Lys2614GlufsTer20) mutation. The two mutations were diagnosed both in genomic DNA from peripheral blood and from MM cells. The potential link between NF1 mutation and the increased risk of MM is discussed in the report.

Multiple myeloma (MM) is characterized by severely imbalanced bone remodeling. In this study, we investigated the potential effect of proteasome inhibitors (PIs), a class of drugs known to stimulate bone formation, on the mechanisms involved in osteocyte death induced by MM cells. First, we performed a histological analysis of osteocyte viability on bone biopsies on a cohort of 37 MM patients with symptomatic disease. A significantly higher number of viable osteocytes was detected in patients treated with a bortezomib (BOR)-based regimen compared with those treated without BOR. Interestingly, both osteocyte autophagy and apoptosis were affected in vivo by BOR treatment. Thereafter, we checked the in vitro effect of BOR to understand the mechanisms whereby BOR maintains osteocyte viability in bone from MM patients. We found that osteocyte and preosteocyte autophagic death was triggered during coculturing with MM cells. Our evaluation was conducted by analyzing either autophagy markers microtubule-associated protein light chain 3 beta (LC3B) and SQSTM1/sequestome 1 (p62) levels, or the cell ultrastructure by transmission electron microscopy. PIs were found to increase the basal levels of LC3 expression in the osteocytes while blunting the myeloma-induced osteocyte death. PIs also reduced the autophagic death of osteocytes induced by high-dose dexamethasone (DEX) and potentiated the anabolic effect of PTH(1-34). Our data identify osteocyte autophagy as a new potential target in MM bone disease and support the use of PIs to maintain osteocyte viability and improve bone integrity in MM patients.

Muscle involvement in AL amyloidosis is a rare condition, and the diagnosis of amyloid myopathy is often delayed and underdiagnosed. Amyloid myopathy may be the initial manifestation and may precede the diagnosis of systemic AL amyloidosis. Here, we report the case of a 73-year-old man who was referred to our center for a monoclonal gammopathy of undetermined significance (MGUS) diagnosed since 1999. He reported a progressive weakness of proximal muscles of the legs with onset six months previously. Muscle biopsy showed mild histopathology featuring alterations of nonspecific type with a mixed myopathic and neurogenic involvement, and the diagnostic turning point was the demonstration of characteristic green birefringence under cross-polarized light following Congo red staining of perimysial vessels. Transmission electron microscopy (TEM) confirmed amyloid fibrils around perimysial vessels associated with collagen fibrils. A stepwise approach to diagnosis and staging of this disorder is critical and involves confirmation of amyloid deposition, identification of the fibril type, assessment of underlying amyloidogenic disorder, and evaluation of the extent and severity of amyloidotic organ involvement.

The bone marrow provides a protected environment for generating a vast array of cell types. Bones are thus a dynamic source of structural components and soluble factors used either locally or at a distance from their site of production. We discuss the role of ectoenzymes in the bone niche where human myeloma grows. Selected ectoenzymes have been tested for their ability to promote production of substrates involved in signaling, synthesis of growth factors and hormones, and modulation of the immune response. Because of the difficulty of simultaneously tracking all these activities, we narrow our focus to events potentially influencing synthesis of adenosine (ADO), an important regulator of multiple biological functions, including local immunological tolerance. Our working hypothesis, to be discussed and partially tested herein, is that CD38, and likely BST1/CD157--both NAD(+) -consuming enzymes, are active in the myeloma niche and lead a discontinuous chain of ectoenzymes whose final products are exploited by the neoplastic plasma cell as part of its local survival strategy. Coadjuvant ectoenzymes include PC-1/CD203a, CD39, and CD73, which control the production of ADO. Results discussed here and from ongoing experiments indicate that the myeloma niche hosts the canonical, as well as alternative, pathways of ADO generation. Other possibilities are presented and discussed.

Low bone marrow oxygen tension and hypoxia-inducible factor-1α overexpression characterize patients with multiple myeloma: role on the transcriptional and proangiogenic profiles of CD138 + cells

International audience; The anti-tumoral effect of lenalidomide is increased in vivo by hypoxia-inducible factor (HIF)-1α inhibition in myeloma cells We investigated the effect of stable suppression of hypoxia inducible factor (HIF)-1α in myeloma cells on sensitivity to lenalidomide (LEN) in vivo. We found that the in vivo anti-tumoral effect of LEN is enhanced by HIF-1α suppression in myeloma cells. It has been reported that HIF-1α is over-expressed by myeloma cells 1-4 and that HIF-1α suppression significantly blocks myeloma-induced angiogenesis, and reduces both tumoral burden and bone destruction in vivo in multiple myeloma (MM) mouse models. 3 The potential effects of HIF-1α modulation on drug sensitivity in MM cells are not known and are currently under investigation. The immunomodulatory drugs (IMiDs®), including LEN, are a class of drugs derived from thalidomide 4 able to exert anti-myeloma effects by the selective Cereblon-dependent destruction of IKZF proteins, 5,6 either through a direct action on MM cell proliferation and survival, 7 or through indirect immunomodulatory and anti-angiogenic effects. 7 Previous data indicated that HIF-1α inhibition did not increase the anti-proliferative in vitro effect of bortezomib on MM cells; 2,3 this drug induces a strong downregula-tion of HIF-1α in MM cells. 2 We recently reported that HIF-1α knockdown in the human myeloma cell line (HMCL) JJN3 potentiated the in vitro effect of LEN treatment (48-72 h) on cell proliferation through a significant upregulation of p27 without changing cell viability. 3 It has been consistently reported that LEN only slightly down-regulated HIF-1α expression in MM cells. 2 Such evidence has provided the rationale to investigate the effect of stable suppression of HIF-1α in myeloma cells on LEN sensitivity in vivo. Therefore, in the present study, we first inhibited HIF-1α in three HMCLs (JJN3, OPM2 and H929) using an anti-HIF1α lentiviral shRNA pool, as previously described. 3 H929 showed a very high mortality rate after anti-HIF1α lentiviral infection (data not shown) and were not used for the subsequent in vivo experiments. We assessed the effect of LEN in combination with HIF-1α inhibition in a non-obese diabetic/severe combined immunodeficiency (NOD/SCID) subcutaneous in vivo mouse model. 3 Different groups of animals (5 animals in each group) of two sets of independent experiments were injected with JJN3 pLKO.1 (empty vector) or JJN3 anti-HIF1α. When tumors became palpable (approx. 7-10 days after injection) mice were treated with LEN 5 mg/kg (Selleckchem, Houston, TX, USA) or vehicle (DMSO) using the intraperitoneal route. The same mouse model, grouping strategy and treatment conditions were used for OPM2 pLKO.1 or OPM2 anti-HIF1α. After three weeks, we evaluated tumor volume and weight, as previously described, 3 and immunohisto-chemistry was used to evaluate the microvascular density (MVD) and checked by CD34 immunostaining (Santa Cruz, Dallas, TX, USA). 3 In addition, in the first set of mice experiments, the expression of p27 (Abcam, Cambridge, UK) was evaluated by immunohistochem-istry. The expression of S-phase kinase-associated protein 2 (SKP2), a p27 inhibitor, expression of the HIF-1α target key mediator of glycolysis and tumoral growth, Hexokinase II (HK2), and levels of pERK 1/2, and total Caspase-3 (Casp-3) were evaluated in the ex vivo plasma-cytoma lysates by western blot using the following anti-bodies: SKP2, Casp-3 (Santa Cruz, Dallas, TX, USA), HK2, pERK 1/2, (Cell Signaling, Danvers, MA, USA). b-actin was used as internal control (Millipore

Myeloid sarcoma is a disease that involves first the breast with rapid systemic dissemination. There is no scientific standard consensus on surgical and medical treatment of myeloid sarcoma of the breast and there is no role for radical surgery because chemotherapy and radiotherapy are required for longer survival. Surgery is needful in investigatory work-up to define immunohistochemistry diagnosis. We reported one case of 39-year-old Caucasian female with myeloid sarcoma without systemic involvement that was admitted to our Operative Unit for breast neoplasm. The patient is alive 19 months after surgery she is in good health, without relapse and she never developed neither clinical nor hematologic signs of myelo-proliferative disease. We can deduce that our therapeutic strategy was correct but we can’t consider the disease completely cured because of its aggressiveness.

Multiple myeloma (MM) is characterized by severely imbalanced bone remodeling. In this study, we investigated the potential effect of proteasome inhibitors (PIs), a class of drugs known to stimulate bone formation, on the mechanisms involved in osteocyte death induced by MM cells. First, we performed a histological analysis of osteocyte viability on bone biopsies on a cohort of 37 MM patients with symptomatic disease. A significantly higher number of viable osteocytes was detected in patients treated with a bortezomib (BOR)-based regimen compared with those treated without BOR. Interestingly, both osteocyte autophagy and apoptosis were affected in vivo by BOR treatment. Thereafter, we checked the in vitro effect of BOR to understand the mechanisms whereby BOR maintains osteocyte viability in bone from MM patients. We found that osteocyte and preosteocyte autophagic death was triggered during coculturing with MM cells. Our evaluation was conducted by analyzing either autophagy markers microtubule-associated protein light chain 3 beta (LC3B) and SQSTM1/sequestome 1 (p62) levels, or the cell ultrastructure by transmission electron microscopy. PIs were found to increase the basal levels of LC3 expression in the osteocytes while blunting the myeloma-induced osteocyte death. PIs also reduced the autophagic death of osteocytes induced by high-dose dexamethasone (DEX) and potentiated the anabolic effect of PTH(1-34). Our data identify osteocyte autophagy as a new potential target in MM bone disease and support the use of PIs to maintain osteocyte viability and improve bone integrity in MM patients.

Galectin-1 (Gal-1) is involved in tumoral angiogenesis, hypoxia and metastases. Actually the Gal-1 expression profile in multiple myeloma (MM) patients and its pathophysiological role in MM-induced angiogenesis and tumoral growth are unknown. In this study, we found that Gal-1 expression by MM cells was upregulated in hypoxic conditions and that stable knockdown of hypoxia inducible factor-1α significantly downregulated its expression. Therefore, we performed Gal-1 inhibition using lentivirus transfection of shRNA anti-Gal-1 in human myeloma cell lines (HMCLs), and showed that its suppression modified transcriptional profiles in both hypoxic and normoxic conditions. Interestingly, Gal-1 inhibition in MM cells downregulated proangiogenic genes, including MMP9 and CCL2, and upregulated the antiangiogenic ones SEMA3A and CXCL10. Consistently, Gal-1 suppression in MM cells significantly decreased their proangiogenic properties in vitro. This was confirmed in vivo, in two different mouse models injected with HMCLs transfected with anti-Gal-1 shRNA or the control vector. Gal-1 suppression in both models significantly reduced tumor burden and microvascular density as compared with the control mice. Moreover, Gal-1 suppression induced smaller lytic lesions on X-ray in the intratibial model. Overall, our data indicate that Gal-1 is a new potential therapeutic target in MM blocking angiogenesis.

Inflammatory pseudotumour (IPT) of the lymph nodes is an uncommon, self-limiting, non-neoplastic proliferation of spindle cells, associated with a polymorphous inflammatory cell infiltrate embedded in a collagen-rich stroma and a variable degree of fibrosis, arising in the nodal parenchyma. Its clinical picture is characterised by site-specific signs and the presence, in most cases, of constitutional symptoms. The pathogenesis of IPT is unknown, but it has been interpreted as an aberrant reactive condition of the nodal connective framework, possibly related to viral infections or chronic inflammatory conditions. Its prognosis is usually favourable. We here report the simultaneous onset of seronegative rheumatoid arthritis (RA) and nodal IPT in a 31-year-old woman. Notably, in the nodal biopsy the coexistence of rheumatoid nodules, as well as histological and immunohistochemical features of IPT, was observed. To our knowledge, such an association has not been previously reported and the hypothesis that IPT could represent an unusual epiphenomenon of an RA-related chronic inflammatory response is suggested.

BACKGROUND Amplification of the HER-2/neu oncogene has been proposed as a target for antibody-based therapies and as a predictor of chemoresponsiveness in advanced breast carcinoma. Few studies have concentrated on HER-2/neu gene evaluation by fluorescence in situ hybridization (FISH) on distant metastatic sites and none have been performed on cytologic samples. The current study evaluated HER-2/neu amplification by FISH on cytologic samples obtained from distant metastatic lesions of breast carcinoma to update HER-2/neu characterization through a safe and easier procedure than biopsy. METHODS Twenty-two cytologic samples from distant metastases (12 hepatic samples, 4 skin samples, 3 pleural samples, and 3 peritoneal samples) were submitted to HER-2/neu evaluation by FISH. Seventeen corresponding primary breast tumors also were evaluated by FISH on paraffin histologic sections or on destained archival cytologic smears. RESULTS Seven of the 22 metastases (32%) were amplified. Amplification was observed in 4 of the 12 liver metastases, in 1of the 3 ascitic fluid specimens, and in 2 of the 4 skin metastases. In all the three pleural fluid specimens, HER-2/neu was unamplified. Matched results from primary and metastatic lesions were obtained in 14 cases (5 were amplified and 9 were unamplified on both primary and metastatic tumors). CONCLUSIONS The results of the current study emphasized the feasibility and advantages of two rapid and very informative techniques, such as fine-needle aspiration biopsy and FISH. Both procedures were performed to ascertain the malignant nature of a suspicious lesion and to obtain predictive markers for response. Since the advent of trastuzumab, the characterization of the molecular profile in metastatic breast disease has become increasingly important for targeted therapy selection. Cancer (Cancer Cytopathol) 2003;99:310–5. © 2003 American Cancer Society.

The bone marrow provides a protected environment for generating a vast array of cell types. Bones are thus a dynamic source of structural components and soluble factors used either locally or at a distance from their site of production. We discuss the role of ectoenzymes in the bone niche where human myeloma grows. Selected ectoenzymes have been tested for their ability to promote production of substrates involved in signaling, synthesis of growth factors and hormones, and modulation of the immune response. Because of the difficulty of simultaneously tracking all these activities, we narrow our focus to events potentially influencing synthesis of adenosine (ADO), an important regulator of multiple biological functions, including local immunological tolerance. Our working hypothesis, to be discussed and partially tested herein, is that CD38, and likely BST1/CD157--both NAD(+) -consuming enzymes, are active in the myeloma niche and lead a discontinuous chain of ectoenzymes whose final products are exploited by the neoplastic plasma cell as part of its local survival strategy. Coadjuvant ectoenzymes include PC-1/CD203a, CD39, and CD73, which control the production of ADO. Results discussed here and from ongoing experiments indicate that the myeloma niche hosts the canonical, as well as alternative, pathways of ADO generation. Other possibilities are presented and discussed.

This review summarizes the events ruled by CD38 shaping the bone marrow environment, recapitulating old and new aspects derived from the body of knowledge on the molecule. The disease models considered were myeloma and chronic lymphocytic leukemia (CLL). CD38 has been analyzed considering its twin function as receptor and enzyme, roles usually not considered in clinics, where it is used as a routine marker. Another aspect pertaining basic science concerns the role of the molecule as a member of an ectoenzyme network, potentially metabolizing soluble factors not yet analyzed (e.g., NAD+, ATP, NAM) or influencing hormone secretion (e.g., oxytocin). The last point is focused on the use of CD38 as a target of an antibody-mediated therapeutic approach in myeloma and CLL. A recent observation is that CD38 may run an escape circuit leading to the production of adenosine. The generation of local anergy may be blocked by using anti-CD38 antibodies. Consequently, not only might CD38 be a prime target for mAb-mediated therapy, but its functional block may contribute to general improvement in cancer immunotherapy and outcomes.

A 64-year-old man with chronic liver disease presented with dyspnoea, and a chest contrast computed tomography (CT) was performed to evaluate the suspect of pulmonary embolism ( Panel A ). A mass occupying the right atrium, of the same density of the myocardium at …

Myelodysplastic Syndrome (MDS) is a multifaceted disease of Hematopoietic Stem Cells characterized by myeloproliferation associated with mono- or pan-cytopenia, ultimately leading to an advantageous clonal growth of frankly leukemic cells. Although the disruption of bone marrow (BM) architecture and alterations of differentiated hematopoietic compartments have been repeatedly described, the potential involvement of the structural remodeling and redistribution of hematopoietic progenitors within the BM on the evolution of MDS has been poorly investigated. The aim of our study was to determine whether the number and localization of CD34pos progenitors and vascular structures are differentially affected in MDS subcategories and whether these changes are associated with disease progression. Thus, the morphometric evaluation of the number and linear distance from the endosteal surface (PT: paratrabecular 21mm) of capillaries, sinusoids, arterioles and CD34pos progenitors was performed by immunohistochemistry on BM biopsies from 97 consecutive MDS patients (12 RA; 2 RCUD; 19 RCMD; 3 RARS-T; 2 5q-; 20 RAEB-1; 27 RAEB-2; 12 U-MDS) in stable or evolving disease and in 15 cases that progressed to AML. Controls (CTR) were represented by 22 disease-free BM biopsies. Risk stratification was based on IPSS. Compared to CTR, capillary density linearly increased in IT marrow from RA thorough RAEB-1, with a subsequent progressive drop in RAEB-2 and AML. Sinusoid density was reduced in MDS and progressively declined from RAEB-1 through AML. PT and IT arterioles increased by more than 3-fold in MDS vs CTR although a progressive rarefaction associated with an increased thickness was measured from RA thorough RAEB-2. A marked rise in arteriolar number was also observed in AML. As expected, CD34pos cell number progressively increased with the severity of the disease, however, a sharp redistribution from PT to perisinusoid and fat areas within the IT marrow was documented (Figure). Intriguingly, the BM redistribution of vascular structures had higher impact than the increased number of CD34pos progenitors to identify high risk MDS and the subset of MDS patients who subsequently developed AML. Finally, patients responsive to azacytidine displayed a reduced number and a topographic redistribution of CD34pos cells together with an increased BM capillarization. BM structural remodelling and rearrangement of hematopoietic progenitors characterize the evolution of MDS. The prognostic significance and the predictive value of these parameters may be translated in new therapeutic approaches able to improve patient management. Figure Figure. Disclosures Giuliani: Janssen: Research Funding; Celgene: Research Funding.

Basic fibroblast growth factor (bFGF) is a growth factor with proangiogenetic properties. Elevated bone marrow (BM) and peripheral serum bFGF levels have been reported in patients with multiple myeloma (MM)[1][1]-[3][2]; however, the source of bFGF in patients with MM is not completely elucidated.

Hypoxia-inducible transcription factor-1 (HIF-1α) is overexpressed in multiple myeloma (MM) cells within the hypoxic microenvironment. Herein, we explored the effect of persistent HIF-1α inhibition by a lentivirus short hairpin RNA pool on MM cell growth either in vitro or in vivo and on the transcriptional and pro-angiogenic profiles of MM cells. HIF-1α suppression did not have a significant impact on MM cell proliferation and survival in vitro although, increased the antiproliferative effect of lenalidomide. On the other hand, we found that HIF-1α inhibition in MM cells downregulates the pro-angiogenic genes VEGF, IL8, IL10, CCL2, CCL5 and MMP9. Pro-osteoclastogenic cytokines were also inhibited, such as IL-7 and CCL3/MIP-1α. The effect of HIF-1α inhibition was assessed in vivo in nonobese diabetic/severe combined immunodeficiency mice both in a subcutaneous and an intratibial MM model. HIF-1α inhibition caused a dramatic reduction in the weight and volume of the tumor burden in both mouse models. Moreover, a significant reduction of the number of vessels and vascular endothelial growth factors (VEGFs) immunostaining was observed. Finally, in the intratibial experiments, HIF-1α inhibition significantly blocked bone destruction. Overall, our data indicate that HIF-1α suppression in MM cells significantly blocks MM-induced angiogenesis and reduces MM tumor burden and bone destruction in vivo, supporting HIF-1α as a potential therapeutic target in MM.

The involvement of osteocytes in multiple myeloma (MM)-induced osteoclast (OCL) formation and bone lesions is still unknown. Osteocytes regulate bone remodelling at least partially, as a result of their cell death triggering OCL recruitment. In this study, we found that the number of viable osteocytes was significantly smaller in MM patients than in healthy controls, and negatively correlated with the number of OCLs. Moreover, the MM patients with bone lesions had a significantly smaller number of viable osteocytes than those without, partly because of increased apoptosis. These findings were further confirmed by ultrastructural in vitro analyses of human preosteocyte cells cocultured with MM cells, which showed that MM cells increased preosteocyte death and apoptosis. A micro-array analysis showed that MM cells affect the transcriptional profiles of preosteocytes by upregulating the production of osteoclastogenic cytokines such as interleukin (IL)-11, and increasing their pro-osteoclastogenic properties. Finally, the osteocyte expression of IL-11 was higher in the MM patients with than in those without bone lesions. Our data suggest that MM patients are characterized by a reduced number of viable osteocytes related to the presence of bone lesions, and that this is involved in MM-induced OCL formation.

The development of sentinel lymph node biopsy in breast cancer disease and the increasing of using adjuvant systemic therapy provide a rational reduction of axillary dissection in patients with Sentinel Lymph Nodes free from breast cancer cells. The aim of our study was to assess the state of the perisentinel lymph nodes removed and how these nodes can provide further information about the status of the axillary lymph nodes.We have analysed data about 319 patients undergoing surgery for benign and malignant breast disease from January 2007 to July 2010; 134 cases were subjected to the sentinel lymph node biopsy; 29 cases of these patients had the presence of perisentinel lymph nodes at histological examination. Before the intervention, we have used colloidal albumin marked with 99mtc to select the sentinel lymph node; during the intervention, we identified by probe the ipercaptant lymph node, consequently we removed and sent it to histological extemporaneous definitive examination.In 134 Sentinel Lymph Nodes examined, 15 resulted positive for breast cancer cells at extemporaneous examination. In these cases, we decided to proceed with an axillary dissection in the same operative session, with the discovery of axillary lymph nodes metastases in 3 cases on 15 (20%). The positive predictive value of sentinel lymph node in case of positivity was 0.2. 8 cases (6,7% of the lymph nodes sentinel biopsy made) were negative to extemporaneous examination and positive to definitive histological examination for presence of micrometastasis. In 8 axillary dissection, 3 patients were positive for the presence of metastasis. We have analysed with the test "t-student" these data divided on age and the value of Ki-67. Then we calculated the predictive positive and negative value (patients with negative sentinel lymph node: Mean age (+/- sd) =61.93 +/- 13.8 years, ki-67=10.87 +/- 5.78; patients with positive sentinel lymph node: Age mean (+/- sd) = 64 +/- 12 36 years, ki-67=14.08 +/- 8.005). The study showed no statistically significant differences between the positive and negative sentinel lymphnodes about the age (p=0.58) and the Ki-67 (p=0.184). In the 29 cases in which the sentinel lymph node was negative at extemporaneous histological examination and in which were removed the perisentinel lymph nodes, resulted negative at definitive histological examination, the negative predictive value was equal to 1.The method of sentinel lymph node has demonstrated to be a reproducible, reliable and safe technique. The positivity of sentinel lymph node at final examination (micrometastasis, cells isolated) in case of extemporaneous examination negative for breast cancer cells, determines specifical considerations on surgical indication to axillary dissection. We think that in selected cases (age, biological characteristic of cancer) in which perisentinel lymph nodes were removed and free from breast cancer cells, may not be indicated in case of sentinel node positivity the axillary dissection.

Gastric metastases of breast cancer represent a not so rare event in patients affected. In fact, it occurs in 0.3% of cases. Although the introduction of new adjuvant therapies has given rise to an increase in disease free survival and overall survival rates, it has also led to more frequent occurrences of breast cancer metastatic lesions localized in bone, lung/pleura and liver, but above all in the stomach. The authors present three cases of patients suffering from breast cancer with secondary gastric neoplastic lesions from lobular and infiltrating ductal breast cancer. Lobular breast cancer is the histological type mostly involved in disseminated disease, with an incidence of 85% of cases. A review of the literature reveals that authors address the clinical and diagnostic problems of differentiating between a breast cancer metastasis to the stomach and a primary gastric cancer using recent diagnostic strategies to make an early diagnosis. Today practitioners have specific tests to detect early gastric cancer metastases of breast cancer such as endoscopic ultrasound, which provides a better endoscopic definition of the lesions, and immunohistochemical markers, able to distinguish the primary lobular histological type from ductal cancer. Besides, an early diagnosis associated with the latest adjuvant systemic therapies and hormonal treatment, alone or in combination, may grant affected patients a remission with a survival rate of 10-28 months, and a reasonable quality of life. At present the surgical approach should be reserved for selected cases and/or complications.

The lymph node sentinel method is today used for staging the axillary lymph node stations. Ultrasonography is widely available and inexpensive method to study axillary status.One hundred fourteen patients were studied consecutively using axillary ultrasonography and ultrasound guided fine needle aspiration of the lymph node. We used ATL Ultramark 9 with 5-7.5 MHz multiple frequency linear probe or Aloka SSDD-1400 with 7.5 MHz linear probe.One hundred fourteen patients were examined; six were excluded because of definitive histological diagnosis of non-infiltrating carcinoma. 106 had monofocal carcinomas, 2 had bifocal carcinoma in 104/108 ultrasonography was carried out successfully. The axillary cytological examination was positive in 18 cases (17.3%) who were subjected to axillary examination. 86 patients were subjected to sentinel lymph node biopsy: positive 13 cases (6 micrometastases). 31 cases/104 (29.8%) showed positive axilla. Sensitivity of ultrasonography was 58%, 100%specificity. Predictive positive value 100%, Negative value 84.9% for an accuracy of 87.5%.Ultrasonography is useful in all cases eligible to sentinel lymph node examination; the minimum cost of the procedure and of the human resources is amply rewarded by the direct indication for surgical axillary dissection in case of a positive result (17.3% in our experience).

A 58-year-old woman underwent a curative total abdominal hysterectomy with bilateral salpingo-oophorectomy for a uterine carcinosarcoma. Fifteen months later, PET and CT scan revealed three pulmonary nodules and multiple lymphadenopathy. An atypical lung segmentectomy with dissection of the regional lymph nodes was performed. Two of the three nodules showed morphological and immunohistochemical profiles consistent with the diagnosis of large-cell neuroendocrine carcinoma (LCNEC). The third nodule, the surrounding pulmonary parenchyma and lymph nodes showed diffuse sarcoid granulomatosis. Re-review of the histology of the uterine carcinosarcoma revealed LCNEC morphology with immunohistochemical and genetic profiles identical to the lung cancers, finally deemed as metastatic deposits. Systemic sarcoidosis was ruled out. To our knowledge this is the first case of uterine carcinosarcoma with LCNEC features metastatic to the lung and occurring in association with sarcoid reaction.

The proteasome inhibitor bortezomib may increase osteoblast-related markers in multiple myeloma (MM) patients; however, its potential osteoblastic stimulatory effect is not known. In this study, we show that bortezomib significantly induced a stimulatory effect on osteoblast markers in human mesenchymal cells without affecting the number of osteoblast progenitors in bone marrow cultures or the viability of mature osteoblasts. Consistently we found that bortezomib significantly increased the transcription factor Runx2/Cbfa1 activity in human osteoblast progenitors and osteoblasts without affecting nuclear and cytoplasmatic active β-catenin levels. Consequently a stimulatory effect of bortezomib on bone nodule formation was also demonstrated in osteoblast progenitors. These in vitro observations were confirmed in vivo by the finding of a significant increase in the number of osteoblastic cells × mm2 of bone tissue and in the number of Runx2/Cbfa1-positive osteoblastic cells that was observed in MM patients who responded to bortezomib. Our in vitro and in vivo observations support the hypothesis that a direct stimulatory effect on bone formation process could occur during bortezomib treatment.

The malignant plasma cells (PC) dependence on the bone marrow (BM) microenvironment is a main feature of multiple myeloma (MM), mainly due to high expression of cell adhesion molecules including CD44, CD54 (ICAM1), CD56, CD49d and chemokines receptors such as CXCR4. At the end stage of the disease, a rare MM complication, that may occurs, is a secondary extramedullary involvement without a leukemic phase and, among the extramedullary localizations, the skin is one of the possible sites, due to the physiological homing of PCs. However, the mechanisms behind the extramedullary spread are not completely understood. In a patient with refractory resistant MM, who has developed a cutaneous localization after 16 months from the diagnosis under Bortezomib (BOR) treatment, we analyzed the gene expression profiles (GEPs) by GeneChip U133 Plus 2.0 (Affymetrix), the immunophenotypic and immunohistochemistry (IHC) profiles of MM cells, across the course of the disease. To confirm the results, IHC profiles on selected molecules were then analyzed in other six MM patients with secondary skin involvement without PC leukemia. On BM CD138+ PCs at diagnosis and BM relapse, by GEP analysis, 742 genes resulted differentially expressed. Moreover, a more stringent analysis identified 19 down-regulated and 42 up-regulated genes; data were confirmed by Real Time PCR on selected genes mainly involved in PC homing. At the BM relapse, we found that MM cells expressed CXCR4 and were negative for CD56; moreover, a significant down-regulation of ICAM1 (CD54) and ALCAM was observed together with the up-regulation of MAGE family genes, DKK1 and SEMA3A in the BM relapse sample compared to diagnosis one. At the cutaneous involvement development, 4 months after BM relapse, by IHC analysis, the MM cells localized in the skin showed the expression of both CD56 and CD54. On the other hand, the BM MM cells immunophenotype confirmed the presence of CD56 but showed the lack of CXCR4 expression. IHC for CD54, CD56 and CXCR4 expression was then performed on both skin and bone biopsies of the other patients analyzed. To go further inside on the role of CXCR4 we treated with BOR (5-10nM) for 24-48h human myeloma cell lines (HMCLs) RPMI-8226 and U266, known to be resistant to BOR, evaluating the CXCR4 expression at both mRNA and protein level, by real-time PCR and by cytofluorimetry, respectively. CXCR4 resulted downregulated after BOR treatment in BOR resistant HMCLs. Consistently, the loss of CXCR4 expression was recently associated to BOR resistance and extramedullary disease in a mouse model of MM suggesting that CXCR4 loss can be correlated with BOR resistance and PCs mobilization from BM, leading to an extramedullary disease. In conclusion, our data indicate that the loss of CXCR4 expression by MM cells across the disease progression, together with CD54 and CD56 down-regulation and their re-acquisition at the extramedullary site, are involved driving the escape of PCs from BM to the extramedullary localization in the skin in the context of Bortezomib resistance. Disclosures No relevant conflicts of interest to declare.

The relationship between multiple myeloma (MM) cells and osteoblast (OB)s and osteoclast (OCL)s into the bone marrow (BM) niche has a critical role in the pathophysiology of MM and in the development of bone disease in MM patients. Recently, Daratumumab (DARA), a human anti-CD38 monoclonal antibody has been developed with broad-spectrum killing activity including complement-dependent cytotoxicity (CDC), antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and, at least in part, modulation of CD38 enzymatic activity. In pre-clinical studies, DARA has been shown to effectively kill MM cells and clinical trials are ongoing. However, the effects of DARA in the context of the MM bone niche and on MM-induced bone remodeling alterations are unknown. In this study, we have firstly evaluated the expression profile of CD38 and its related ectoenzymes by bone niche cells and, thereafter, we investigated the effect of DARA on OCL and OB formation and bone remodeling. The study design included immunohistochemistry for CD38, CD73, CD39, CD203a (PC-1), CD157 and CD31 on bone biopsies in a cohort of 38 patients with newly diagnosed MM and 14 patients with monoclonal gammopathy of uncertain significance (MGUS). Moreover, the expression profile of these antigens was performed by flow cytometry on primary BM CD138+ cells (sample number=16), mesenchymal stromal cells, OBs, monocytes and OCLs and on the related human cell lines. As expected, we found that CD38 was highly expressed by MM cells that were also positive for CD203a and for CD39 and CD31 at variable level but not for CD157 and CD73. CD38 was also expressed by BM monocytes but not by OBs, OCLs and BM stromal cells. Interestingly, we found that OBs expressed CD73 and CD203a. Any significant difference was not observed in the expression of CD38 and related ectoenzymes between MM and MGUS patients. In line with CD38 expression profile by MM cells and the niche, we further demonstrated that DARA binds both MM cells and monocytes, but not OBs and OCLs. Consistently, we lack to find any significant effect of DARA on OB formation from BM stromal cells or OBs proliferation and survival. Thus, we investigated the effect of DARA (1-25 ug/ml) as compared to human IgG isotype control on OCL formation and activity in the presence of RANKL and M-CSF, using either CD138- cell fraction or purified CD14+ cells from MM BM samples. OCLs were evaluated by both TRAP staining and a fluorimetric osteolysis assay. We found that DARA, between 10 and 25 ug/ml, with a dose dependent effect, significantly inhibited OCL formation and activity from BM mononuclear cells and from the CD138- cell fraction, but not from purified CD14+ cells. The inhibitory effect on OCL formation by DARA was observed when the antibody was present for all the culture period (21-28 days). On the other hand DARA did not show any effect on late OCL progenitors and mature OCLs. Accordingly CD38 expression by monocytes cultured in a pro-osteoclastogenic medium disappeared after 7 days. In conclusion, our data indicate that DARA inhibit osteoclastogenesis, likely mediated by ADCC, targeting monocytes and early OCL progenitors. This evidence supports the use of an anti-CD38 based approach as a treatment for MM bone disease. Disclosures Malavasi: Janssen: Honoraria, Research Funding. Giuliani:Celgene Italy: Other: Research Grant; Janssen Pharamceutical: Other: Research Grant.

The immunomodulatory drugs (IMiDs®) exert an anti-myeloma effect by cereblon-dependent destruction of IKZF proteinseither through a direct action on multiple myeloma (MM) cells or through indirect immunomodulatory and anti-angiogenic effects.Previous data indicated that MM cells overexpress hypoxia inducible factor (HIF)-1α and that HIF-1α suppression significantly blocks MM-induced angiogenesis and reduces in vivo tumoral burden in MM mouse models. Interestingly, it has been recently reported that HIF-1α knock-down in MM cells potentiates the in vitro effect of Lenalidomide (LEN) on cell proliferation without changing cell viability and that LEN is not able to suppress HIF-1α expression in MM cells. These evidences give the rationale design to investigate the in vivo effect of HIF-1α stable suppression in MM cells on LEN sensitivity. Thus, in this study, we assessed the effect of LEN in vivo in combination with HIF-1α inhibition in a non-obese diabetic/severe combined immunodeficiency (NOD/SCID) subcutaneous mouse model using JJN3, a cell line known to be resistant to the cytotoxic effect of LEN. Different groups of animals were injected with JJN3-pLKO.1 (empty vector) or JJN3-anti-HIF1α, obtained by anti-HIF1α lentiviral shRNA pool. When tumors became palpable, mice were treated with LEN (5mg/kg), using the intraperitoneal route. After three weeks, we evaluated tumor volume and weight. Moreover, by immunohistochemistry on ex vivo plasmacytomas, we evaluated the expression of p27 and the microvascular density (MVD), checked by CD34 immunostaining. In addition, the expression of a p27 inhibitor, the S-phase kinase-associated protein 2 (SKP2), the expression of the HIF-1α target key mediator of glycolysis and tumoral growth, Hexokinase II (HK2), and the levels of pERK 1/2, and total Caspase-3 (Casp-3) were evaluated in the ex vivo plasmacytomas lysates by western blot. We found that LEN treatment induced a significant weight and volume reduction of the tumor burden in mice injected with JJN3 anti-HIF1α as compared to JJN3-pLKO.1. The p27 nuclear expression was significantly increased by LEN treatment in JJN3-anti-HIF1α as compared to JJN3 pLKO.1 mice and compared to JJN3-anti-HIF1α mice treated with vehicle. In addition, we demonstrated that LEN in combination with HIF-1α inhibition significantly reduced in vivo the expression of p-ERK1/2, total Casp-3, HK2 and the p27 inhibitor, SKP2. Because it is known that LEN exerts its anti-MM effect targeting the IKZF proteins, we further checked in vitro whether the effect of HIF-1α suppression and LEN treatment combination could be mediated by IKZF proteins modulation. Interestingly, after LEN (2-10µM) treatment we found that both IKZF1 and IKZF3 were not differentially expressed, whereas IRF4 was down regulated, in JJN3-anti-HIF1α as compared to JJN3 pLKO.1. Finally, regarding a possible combinatory effect on the in vivo angiogenesis, we found that both the number of CD34 positive vessels and the MVD were reduced in mice colonized by JJN3-anti-HIF1α as compared to JJN3-pLKO.1. On the other hand, LEN treatment did not further significantly reduce the number of CD34 positive vessels and the MVD. Accordingly, we did not find any significant inhibitory effect by LEN treatment on the main pro-angiogenic molecules in JJN3 anti-HIF1α as compared to JJN3 pLKO.1 even after 72 hours. Overall, our data indicate that HIF-1α suppression in MM cells significantly increases the anti-MM effect of LEN in vivo, mainly through the inhibition of proliferation signaling including the modulation of p27 pathway and the IKZF target protein IRF4, rather than to an anti-angiogenic effect. These data suggest that the combination of LEN and HIF-1α inhibition has a therapeutic rationale in MM. Disclosures No relevant conflicts of interest to declare.

594 Background: Outcomes for women with pT1aN0M0 breast cancers (BC) may vary by biologic subtype. A higher proportion of HER2-positive BCs diagnosed in the interval between scheduled screening rou...

OBJECTIVES The value of HER-2/neu status as a predictor of response to anthracycline-based chemotherapy is still a matter of debate. We evaluated the contribution of HER-2/neu gene amplification and other biologic markers in predicting response to different doses of neoadjuvant anthracycline-based chemotherapy. METHODS Clinical and pathologic records of 115 primary breast cancer patients were reviewed. Forty-eight and 67 patients received high (doxorubicin > or =20 mg/m2/wk; epirubicin > or =30 mg/m2/wk) and moderate-low anthracycline dose intensity regimens, respectively. Pathologic diagnosis, hormonal receptor status (HR), Ki67, and HER-2/neu status were assessed on tumor samples before neoadjuvant chemotherapy. HER-2/neu was determined by fluorescence in situ hybridization (FISH). RESULTS HER-2/neu amplification was observed in 29/115 (25%) tumors, 18 from moderate-low-dose and 11 from high-dose group. In the univariate analysis, a high Ki67 index (> or =20%) and positive clinical axillary nodes were predictive of an objective tumor response (P = 0.033 and 0.001, respectively). In the multivariate analysis, Ki67 was the only factor predictive of response (OR = 3.08, 95% CI = 1.1-8.5, P = 0.03). HER-2/neu status was not a factor in predicting objective response to different anthracycline dose intensities. The same finding was observed with regards to HR and Ki67. CONCLUSIONS In our series, no significant dose-response relationship was found according to HER-2/neu status.

Galectin-1 (Gal-1) is a lectin, involved in several processes related to cancer, including immunosuppression, angiogenesis, hypoxia, and metastases. However, the expression profiles of Gal-1 and its pathophysiological role in multiple myeloma (MM) cell growth, in the relationship between MM cells and the bone marrow (BM) microenvironment and in the MM-induced angiogenesis are unknown and were investigated in this study. Firstly we evaluatedGal-1 expression by CD138+ cells of a dataset of 133 MM patients at diagnosis (GSE16122) and 23 human myeloma cell lines (HMCLs) (GSE6205) or on a proprietary? dataset of primary mesenchymal stromal cells (MSCs) and osteoblasts (OBs) of 16 MM and 4 MGUS. CD138+ cells and HMCLs were positive for LGALS1 with no statistically significant differences. LGALS1 mRNA expression was positively correlated with 154 genes and negatively with 109 genes including ERG1 and SPARC. MSCs cells showed a higher expression of LGALS1 compared to the OBs and MM-OBs showed a higher expression of LGALS1 mRNA than that obtained from healthy subjects. Gene expression profiling (GEP) data were then validated by Real-Time PCR and western blot in freshly purified primary CD138+ and BM MSCs samples as well as in 6 HMCLs and in both human MSC (HS-5 and hMSC-Tert) and osteoblastic cell lines (HOBIT and HOB-01). Moreover, immunohistochemistry analyses on bone biopsies obtained from 12 MM, 9 smoldering MM, 9 MGUS and 3 plasma cell leukemia samples revealed an high level of Gal-1 protein expression by MM cells, OBs and vessels in all the patients tested. Secondly, we evaluated whether Gal-1 expression was regulated by hypoxia and by Hypoxia Inducible Factor-1a (HIF-1a) checking the effect of hypoxic treatment (1% of O2) and HIF-1α inhibition by shRNA lentivirus. We found that Gal-1 was upregulated in HMCLs upon hypoxic treatment and consistently the re-oxygenation process significantly restored the expression level of Gal-1. Interestingly the stable knock-down of HIF-1a significantly down-regulated Gal-1 expression in HMCLs both in normoxic and hypoxic conditions. Thereafter, we explored the effect of persistent Gal-1 inhibition in MM cells and BM microenvironment cells on cell proliferation, survival and the transcriptional and pro-angiogenic profiles. An anti-Gal-1 Lentivirus shRNA was used for Gal-1 stable knock-down in HMCLs (JJN3-anti-Gal-1 and OPM-2-anti-Gal-1) and MSC cell lines (HS-5 and HMSC-Tert) and the Scramble lentiviral vector (JJN3-Scramble and OPM-2-Scramble) was used as the empty control vector. The stable inhibition of Gal-1 did not affect the proliferation rate and viability of both HMCLs and MSC cell lines. On the other hand Gal-1 inhibition by shRNA lentivirus significantly modified the transcriptional profiles of HMCLs and HS-5, evaluated by U133 Plus2.0 Arrays (Affymetrix®) either in normoxic or hypoxic or re-oxygenation conditions. Among the genes significantly modulated by Gal-1 inhibition in HMCLs, we found that pro-angiogenic (eg. CCL2, MMP9) and adhesion molecules (eg. MCAM and STEAP1) were down-regulated by Gal-1 suppression in both normoxic and hypoxic conditions as well as some putative anti-tumoral genes, including EGR1, SPARC and TGFBI, and anti-angiogenic ones, including SEMA3A, were up-regulated by Gal-1 inhibition. In line with these observations, we found that Gal-1 suppression by shRNA significantly decreased the pro-angiogenic proprieties of HMCLs by an in vitro angiogenesis assay. Finally, we found that mice, injected subcutaneously with JJN3-anti-Gal-1 and OPM-2-anti-Gal-1, showed a reduction in the weight and volume of the tumor burden compared to mice inoculated with the JJN3-Scramble and OPM-2-Scramble. Moreover, a significant reduction in the number of CD34 positive vessels X field was observed. In an intratibial mouse model, JJN3-anti-Gal-1, JJN3-Scramble and JJN3 wild type were injected: in the anti-Gal-1 group tumors grew in reduced number and size compared to the Scramble group, moreover JJN3 anti-Gal-1 mice developed fewer and smaller lytic lesions on x-ray compared to the controls. Overall our data indicate that Gal-1 is highly expressed by MM cells and those of the BM microenvironment and that its expression is regulated by hypoxia. Gal-1 shows a role in MM-induced angiogenesis and its inhibition in MM cells significantly reduced tumor growth in vivo, suggesting that Gal-1 is a potential new therapeutic target in MM. Disclosures Giuliani: Celgene Italy: Research Funding.

Osteocytes are critical in the maintenance of bone integrity regulating bone remodeling through the cell death and autophagy, a cellular process stress-induced to prolong cell survival but when induced excessively can cause cell death. Recently we have demonstrated that an increased osteocyte death is involved in multiple myeloma (MM)-induced osteolysis. However the mechanisms involved in this process as well as the effect of the proteasome inhibitors able to stimulate bone formation are not known and have been investigated in this study. Firstly the effect of the proteasome inhibitors BOR and MG262 on osteocyte viability was evaluated in vitro in murine osteocytic cell line MLO-Y4 and in the human pre-osteocytic one HOB-01. Both cell lines were co-coltured for 48 hours in the presence or absence of the human myeloma cell lines (HMCLs) RPMI8226 and JJN3, placed in a traswell insert. The treatment for 12-24 hours with (BOR) (2nM) and MG262 (10nM) significantly blunted MLO-Y4 and HOB-01 cell death. In addition, dexamethasone (DEX)-induced MLO-Y4 apoptosis, obtained at high doses (10-5-10-6 M), was reduced by the treatment with proteasome inhibitors. Interestingly, we found that PTH short-term treatment potentiated the in vitro effects of proteasome inhibitors on DEX-induced osteocyte death. To evaluate the presence of autophagy in osteocytes, we checked the expression of the autophagic marker LC3 both by confocal microscopy and western blot analysis in the co-colture system with MLO-Y4 and RPMI-8226. Prevalence of autophagic cell death and in a lesser extent apoptosis was observed in this system. BOR increased the basal level of LC3 indicating a pro-survival and protective function of autophagy against the BOR-induce stress. On the contrary, when cells undergo to a stronger stress such as in the presence of HMCLs or by treatment with high dose of DEX we found that both proteasome inhibitors BOR and MG262 blocked autophagic cell death in osteocytes. To translate our in vitro evidence in a clinical perspective, thereafter we performed a histological evaluation on bone biopsies of a cohort of 37 newly diagnosis MM patients 31 of them with symptomatic MM and 6 with smoldering MM (SMM). The 55% of patients with MM have evidence of osteolytic lesions at the X-rays survey. Bone biopsies were obtained at the diagnosis and after an average time of 12 months of treatment or observation. Osteocyte viability was evaluated in a total of 500 lacunae per histological sections. A significant increase of the number of viable osteocytes was demonstrated in MM patients treated with BOR-based regimen as compared to those treated without BOR (% median increase: +6% vs. +1.30%; p=0.017). Patients treated with BOR alone showed the highest increase of osteocyte viability, as compared to those either treated without BOR (+11.6% vs. +1.3%, p=0.0019) or treated with BOR plus DEX (+11.6% vs. +4.4%, p=0.01). A reduction of both osteocyte apoptosis and autophagy was demonstrated by TUNEL assays and confocal microscopy. On the other hand, any significant difference was not observed in patients treated with Thalidomide (THAL) or Immunomodulatory drugs (IMiDs) than in those untreated with these drugs (p= 0.7). A multiple regression non-parametric analysis showed that BOR had a significant positive impact on osteocyte viability (p=0.042) whereas THAL/IMiDs as well as Zoledronic acid (ZOL) treatments have not (p=0.2). BOR also counterbalanced the negative effect of DEX treatment (p=0.035). Our data suggest that proteasome inhibitors blunted osteocyte cell death induced by MM cells and DEX through the modulation of the autophagy supporting their use to improve bone integrity in MM patients. Disclosures: Giuliani: Celgene Italy: Research Funding.

Abstract 2947 It has been previously reported that bone marrow (BM) microenvironment is hypoxic in multiple myeloma (MM) patients and that hypoxia inducible factor (HIF)-1α is overexpressed by MM cells. However, the potential role of HIF-1α as a therapeutic target in MM is not known and is currently under investigation. In this study we explored the effect of persistent HIF-1α inhibition by expression of a lentivirus shRNA pool in MM cells on proliferation, survival and transcriptional and pro-angiogenic profiles of MM cells either in vitro or in vivo in mouse models. A HIF-1α Lentivirus shRNA pool was used for HIF-1α stable knock-down in human myeloma cell lines (HMCL)s and the pKLO.1 lentiviral vector was used as the empty control vector. HMCLs were infected and then selected with puromycin. Selected clones were screened for HIF-1α, HIF-1β, HIF-2α and HIF-3α. The transcriptional profiles were evaluated in the HMCL JJN3 cells transduced with shRNA forHIF-1α (JJN3-anti-HIF-1α) and on those infected with the control vector pKLO.1 (JJN3-pKLO.1) by U133 Plus2.0 Arrays (Affymetrix®) either in hypoxic or normoxic conditions. Microarray data were further validated by quantitative real time PCR and by ELISA assays for protein levels. Finally the effect of HIF-1α inhibition in MM cells was assessed in vivo in NOD/SCID mice both in subcutaneous and intratibial models. Together with tumor volume and weight, microvascular density was evaluated by CD34 immunostaining. Cortical bone thickness was determined by microQcT in the intratibial mouse model. Among the genes significantly modulated by HIF-1α inhibition (327 and 361 genes in hypoxic and normoxic condition, respectively), we found that the pro-angiogenic molecules VEGF, IL8, IL10, CCL2, CCL5, MMP9 were down-regulated by HIF-1α inhibition. Interestingly some pro-osteoclastogenic cytokines were also inhibited including IL-7 and CCL3/MIP-1α. In the in vivo mouse models, we found that mice, injected either subcutaneously or intratibially with JJN3-anti-HIF-1α, showed a dramatic reduction in the weight and volume of the tumor burden compared to mice inoculated with the JJN3-pKLO.1. A significant reduction in the number of vessels X field and VEGF immunostaining were observed in both mouse models. Moreover in the intratibial experiments HIF-1α inhibition significantly blocked MM-induced bone destruction. Overall our data indicate that HIF-1α suppression in myeloma cells significantly blocks MM-induced angiogenesis and reduces the MM tumor burden and bone destruction in vivo suggesting that HIF-1α is a potential therapeutic target in MM. Disclosures: No relevant conflicts of interest to declare.