Multiple myeloma (MM)-induced osteoclast (OC) formation occurs in close contact with MM cell infiltration into the bone marrow (BM) due to the imbalance of the receptor activator of NF-kappa-B ligand (RANKL)/osteoprotegerin (OPG) ratio in favor of RANKL in the micorenvironment. Soluble factors including CCL3/MIP-1?, IL7 and IL-3 also contribute to the increased OC formation in MM.The immunomodulatory drugs (IMiDs) directly inhibit OCs, however their effect on the mechanisms involved in MM-induced OC formation are not known and have been investigated in this study. We found that both Lenalidomide (LEN) and Pomalidomide (POM), at concentration ranging reached in vivo, significantly blunted RANKL up-regulation normalizing the RANKL/OPG ratio in human BM osteoprogenitor cells (PreOBs) co-cultured with MM cells and inhibited CCL3/MIP-1? production by MM cells. The reduction of CD49d expression on MM cells, a molecule critically involved in RANKL up-regulation in the micorenvironment, accompanied this effect. Consistently the pro-osteoclastogenic property of the conditioned medium of MM cells co-cultured with PreOBs was reduced in the presence of both IMiDs. By microarray analysis we further investigated the effect of POM and LEN on the transcriptional profile of both MM cells and PreOBs. We found a significant down-regulation in MM cells, in addition to CD49d, of genes belonging to the adhesion molecules family such as ITGA8 and ICAM2 (CD102) induced by both IMiDs compounds. In conclusion our data suggest that POM and LEN inhibits MM-induced OC formation through the inhibition of RANKL/OPG ratio targeting the expression of adhesion molecules by MM cells.
Immunomodulatory drugs lenalidomide and pomalidomide inhibit multiple myeloma-induced osteoclast formation and the RANKL/OPG ratio in the myeloma microenvironment targeting the expression of adhesion molecules.
Cell line, TreatmentView Samples
Myeloma bone disease is characterized by tremendous bone destruction with suppressed bone formation. IL-3 is a multifunctional cytokine that increases myeloma cell growth and osteoclast proliferation while inhibiting osteoblast differentiation. While IL-3 appears to be an attractive therapeutic target for myeloma, attempts at targeting IL-3 have been unsuccessful due to IL-3s effects on normal hematopoiesis. Thus identification of IL-3s downstream effects in MMBD is important for effective targeting of this cytokine in MM. Here we demonstrated that treatment of myeloma patient CD14+ bone marrow monocyte / macrophages with IL-3 induces high levels of Activin A (ActA), a pluripotent TGF- superfamily member that, like IL-3, modulates MMBD by enhancing osteoclastogenesis and inhibiting osteoblasts. We show that IL-3 induced osteoclastogenesis is mediated by ActA and is RANKL independent. Additionally, IL-3 induced ActA secretion is greatest early in osteoclastogenesis and ActA acts early in osteoclastogenesis. Therefore we suggest that therapies targeting ActA production should block IL-3s effects in myeloma bone disease.
Bone marrow monocyte-/macrophage-derived activin A mediates the osteoclastogenic effect of IL-3 in multiple myeloma.
Specimen part, Disease, Disease stage, TreatmentView Samples
In multiple myeloma (MM), hypoxia-inducible transcription factor-1 (HIF-1) is overexpressed in the MM cells of the hypoxic bone marrow (BM) microenvironment. Herein, we explored in MM cells the in vitro and in vivo effects of persistent HIF-1 inhibition by expression of a lentivirus shRNA pool on proliferation, survival and transcriptional and pro-angiogenic profiles. Among the significantly modulated genes (326 and 361 genes in hypoxic and normoxic condition, respectively), we found that HIF-1 inhibition in the human myeloma cell line JJN3 downregulates the pro-angiogenic molecules VEGF, IL8, IL10, CCL2, CCL5, and MMP9. Interestingly, several pro-osteoclastogenic cytokines were also inhibited, such as IL-7 and CCL3/MIP-1. The effect of HIF-1 inhibition was assessed in vivo in NOD/SCID mice both in subcutaneous and intratibial models, indicating in either case a dramatic reduction of weight and volume of the tumor burden as a consequence of HIF-1 knockdown. Moreover, a significant reduction of the number of vessels per field and VEGF immunostaining were observed. Finally, in the intra-tibial experiments, HIF-1 inhibition significantly blocks JJN3-induced bone destruction. Overall, our data indicate that HIF-1 suppression in MM cells significantly blocks MM-induced angiogenesis and reduces both tumor burden and bone destruction in vivo, strongly indicating HIF-1 as an emerging therapeutic target in MM.
Hypoxia-inducible factor (HIF)-1α suppression in myeloma cells blocks tumoral growth in vivo inhibiting angiogenesis and bone destruction.
Specimen part, Cell lineView Samples
Bone marrow monocytes are primarily committed to osteoclast formation. It is, however, unknown whether potential primary alterations are specifically present in bone marrow monocytes from patients with multiple myeloma, smoldering myeloma or monoclonal gammopathy of undetermined significance. We analyzed the immunophenotypic and transcriptional profiles of bone marrow CD14+ monocytes in a cohort of patients with different types of monoclonal gammopathies to identify alterations involved in myeloma-enhanced osteoclastogenesis. The number of bone marrow CD14+CD16+ cells was higher in patients with active myeloma than in those with smoldering myeloma or monoclonal gammopathy of undetermined significance. Interestingly, sorted bone marrow CD14+CD16+ cells from myeloma patients were more pro-osteoclastogenic than CD14+CD16-cells in cultures ex vivo Moreover, transcriptional analysis demonstrated that bone marrow CD14+ cells from patients with multiple myeloma (but neither monoclonal gammopathy of undetermined significance nor smoldering myeloma) significantly upregulated genes involved in osteoclast formation, including IL21RIL21R mRNA over-expression by bone marrow CD14+ cells was independent of the presence of interleukin-21. Consistently, interleukin-21 production by T cells as well as levels of interleukin-21 in the bone marrow were not significantly different among monoclonal gammopathies. Thereafter, we showed that IL21R over-expression in CD14+ cells increased osteoclast formation. Consistently, interleukin-21 receptor signaling inhibition by Janex 1 suppressed osteoclast differentiation from bone marrow CD14+ cells of myeloma patients. Our results indicate that bone marrow monocytes from multiple myeloma patients show distinct features compared to those from patients with indolent monoclonal gammopathies, supporting the role of IL21R over-expression by bone marrow CD14+ cells in enhanced osteoclast formation.
<i>IL21R</i> expressing CD14<sup>+</sup>CD16<sup>+</sup> monocytes expand in multiple myeloma patients leading to increased osteoclasts.
Age, Specimen partView Samples
Galectin-1 (Gal-1) is a lectin, involved in several processes related to cancer, including immunosuppression, angiogenesis, hypoxia, and metastases. Actually, the Gal-1 expression profile in multiple myeloma (MM) and its pathophysiological role in MMinduced angiogenesis and tumoral growth is unknown. Firstly, we found that Gal-1 was expressed by malignant plasma cells in MM patients and that its expression was up-regulated upon hypoxic treatment (1% of O2). Moreover the stable knock-down of Hypoxia Inducible Factor-1 (HIF-1) in MM cells significantly downregulated Gal-1 expression. Thereafter, we performed Gal-1 inhibition by lentivirus shRNA anti-Gal-1 in human myeloma cell lines (HMCLs) showing that its suppression did not affect cell proliferation and survival but modified their transcriptional profiles either in hypoxia or hypoxia condition. Interestingly pro-angiogenic genes including MMP9 and CCL2 were downregulated and those anti-angiogenic SEMA3A and CXCL10 were up-regulated by Gal-1 inhibition in MM cells. Data were also validated by Real time PCR and at protein level. Consistently we found that Gal-1 suppression in MM cells significantly decreased their pro-angiogenic proprieties by an in vitro assay. These evidences were confirmed in mice injected either subcutaneously or intratibially with HMCLs carrying a stable infection with shRNA anti-inhibition of Gal-1 or with the control vector cell line. Gal-1 suppression in both models showed a significant reduction in the tumoral burden and microvascular density compared to the control mice. Moreover, Gal-1 suppression induced smaller lytic lesions on x-ray in the intratibially model. Overall, our data indicate that Gal-1 is a new potential therapeutic target in MM.
Galectin-1 suppression delineates a new strategy to inhibit myeloma-induced angiogenesis and tumoral growth in vivo.
Specimen part, Cell lineView Samples
Genes are up and down regualted in DRG and spinal dorsal cord after peripheral nerve injury Overall design: WT male adult with sciatic and femoral nerve transection 7 days, RNA was purified from ipilateral or contralateral L4-L6 DRGs or lumbar spinal dorsal cords
Injured sensory neuron-derived CSF1 induces microglial proliferation and DAP12-dependent pain.
No sample metadata fieldsView Samples
Adipose tissue plays an important role in storing excess nutrients and preventing ectopic lipid accumulation in other organs. Obesity leads to excess lipid storage in adipocytes, resulting in the generation of stress signals and the derangement of metabolic functions. SIRT1 is an important regulatory sensor of nutrient availability in many metabolic tissues. Here we report that SIRT1 functions in adipose tissue to protect from the development of inflammation and obesity under normal feeding conditions, and the progression to metabolic dysfunction under dietary stress. Genetic ablation of SIRT1 from adipose tissue leads to gene expression changes that highly overlap with changes induced by high fat diet in wild type mice, suggesting that dietary stress signals inhibit the activity of SIRT1. Indeed, we show that high fat diet induces the cleavage of SIRT1 in adipose tissue by the inflammation-activated caspase-1, providing a link between dietary stress and predisposition to metabolic dysfunction.
High-fat diet triggers inflammation-induced cleavage of SIRT1 in adipose tissue to promote metabolic dysfunction.
No sample metadata fieldsView Samples
We report the application of low cell number sequencing of identifiable Drosophila melanogaster neurons following behavior. We demonstate the feasibility of identifying the transcriptome of 5 Mushroom Body output Neurons and 2 classes of Kenyon Cells. We find these neurons display a diverse repertoire of receptors and signaling transcripts. This information alone seems to be enough to identify each class of neurons in the study. In additional we show that aversive long-term memory induces changes in gene transcript levels in a subset of these neurons. This study provides a framework for identifying neuronal classes in Drosophila melanogaster and gaining insight into the interplay between behavior and gene regulation. Overall design: 5 Mushroom Body output neurons and 2 classes of kenyon cells are used to look at general gene expression and changes following aversive long term memory. Paired control and trained animals were used and a minimum of 4 pairs up to 6 pairs. Animals were of the same background (w1118). Animals were aged and parental matched. Cells were harvested at the same chronological time for the animals across all experiments. All animals were exposed to 1 minute of each odor and 1 minute of a series of 12 5second 60V shocks. This was considered one block and then the animals had spaced training of each block so there was a 10 minute break between 8 blocks of training. Trained animals had an odor paired with a shock, control animals received the shock then the odor stimulus. All cells were harvested usign a patch pipet from living animals on an electrophysiology rig within a half hour of the end of training. Cells were amplified using the Clontech SMARTer Ultra Low Input RNA version 2 High Volume kit. 2 Brain samples were also collected and 3-4 whole fly samples for each genotype were collected to account for background differences across flies.
Cell-Type-Specific Transcriptome Analysis in the Drosophila Mushroom Body Reveals Memory-Related Changes in Gene Expression.
We analyzed gene expression profiles of myeloma cells belonging to the group of bas prognosis RPMI 8226 and LP1 expressing either the GFP protein or a cyclin D1-GFP fusion protein
Cyclin D1 sensitizes myeloma cells to endoplasmic reticulum stress-mediated apoptosis by activating the unfolded protein response pathway.
Specimen part, Cell lineView Samples
In this study we showed that rat XEN cells grown in the presence of a GSK3 inhibitor exhibited enhanced formation of cell contacts and decreased motility. In contrast, treatment with forskolin induced the PE formation and epithelial-mesenchymal transition (EMT) in rat XEN cells. Using microarray and real-time PCR assays, we found that VE versus PE formation of rat XEN cells was correlated with change in expression levels of VE or PE marker genes. Similar to forskolin, EMT was prompted upon treatment of rat XEN cells with recombinant parathyroid hormone related peptide (PTHRP), an activator of the cAMP pathway in vivo. Taken together, our data suggest that rat XEN cells are PrE-like cells. The activation of Wnt pathway in rat XEN cells leads to the acquisition of VE characteristics, whereas the activation of the PTHRP/cAMP pathway leads to EMT and the formation of PE.
Activation of the PTHRP/adenylate cyclase pathway promotes differentiation of rat XEN cells into parietal endoderm, whereas Wnt/β-catenin signaling promotes differentiation into visceral endoderm.
Specimen partView Samples