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Functional alterations in irritable bowel syndrome have been associated with defects in bioenergetics and the mitochondrial network. Effects of high fat, adequate-protein, low carbohydrate ketogenic diet (KD) involve oxidative stress, inflammation, mitochondrial function, and biogenesis. The aim was to evaluate the KD efficacy in reducing the effects of stress on gut mitochondria. Newborn Wistar rats were exposed to maternal deprivation to induce IBS in adulthood. Intestinal inflammation (COX-2 and TRL-4), cellular redox status (SOD 1, SOD 2, PrxIII, mtDNA oxidatively modified purines), mitochondrial biogenesis (PPAR-γ, PGC-1α, COX-4, mtDNA content), and autophagy (Beclin-1, LC3 II) were evaluated in the colon of exposed rats fed with KD (IBD-KD) or standard diet (IBS-Std), and in unexposed controls (Ctrl). IBS-Std rats showed dysfunctional mitochondrial biogenesis (PPAR-γ, PGC-1α, COX-4, and mtDNA contents lower than in Ctrl) associated with inflammation and increased oxidative stress (higher levels of COX-2 and TLR-4, SOD 1, SOD 2, PrxIII, and oxidatively modified purines than in Ctrl). Loss of autophagy efficacy appeared from reduced levels of Beclin-1 and LC3 II. Feeding of animals with KD elicited compensatory mechanisms able to reduce inflammation, oxidative stress, restore mitochondrial function, and baseline autophagy, possibly via the upregulation of the PPAR-γ/PGC-1α axis.

Grapes contain many flavonoid and non-flavonoid compounds with anticancer effects. In this work we fully characterized the polyphenolic profile of two grape skin extracts (GSEs), Autumn Royal and Egnatia, and assessed their effects on Polyunsaturated Fatty Acid (PUFA) membrane levels of Caco2 and SW480 human colon cancer cell lines. Gene expression of 15-lipoxygenase-1 (15-LOX-1), and peroxisome proliferator-activated receptor gamma (PPAR-&gamma, ), as well as cell morphology, were evaluated. The polyphenolic composition was analyzed by Ultra-High-Performance Liquid Chromatography/Quadrupole-Time of Flight mass spectrometry (UHPLC/QTOF) analysis. PUFA levels were evaluated by gas chromatography, and gene expression levels of 15-LOX-1 and PPAR-&gamma, were analyzed by real-time Polymerase Chain Reaction (PCR). Morphological cell changes caused by GSEs were identified by field emission scanning electron microscope (FE-SEM) and photomicrograph examination. We detected a different profile of flavonoid and non-flavonoid compounds in Autumn Royal and Egnatia GSEs. Cultured cells showed an increase of total PUFA levels mainly after treatment with Autumn Royal grape, and were richer in flavonoids when compared with the Egnatia variety. Both GSEs were able to affect 15-LOX-1 and PPAR-&gamma, gene expression and cell morphology. Our results highlighted a new antitumor mechanism of GSEs that involves membrane PUFAs and their downstream pathways.

Background Inflammatory bowel disease (IBD), including Crohn disease (CD) and ulcerative colitis (UC), is a multifactorial disorder characterized by chronic inflammation and altered gut barrier function. Dysbiosis, a condition defined by dysregulation of the gut microbiome, has been reported in patients with IBD and in experimental models of colitis. Although several factors have been implicated in directly affecting gut microbial composition, the genetic determinants impacting intestinal dysbiosis in IBD remain relatively unknown. Methods We compared the microbiome of normal, uninflamed wild-type (WT) mice with that of a murine model of UC (ie, Winnie strain). Winnie mice possess a missense mutation in Muc2 that manifests in altered mucus production as early as 4 weeks of age, with ensuing colonic inflammation. To better address the potential role of mutant Muc2 in promoting dysbiosis in Winnie mice, we evaluated homozygous mutant mice (Winnie-/-) with their WT littermates that, after weaning from common mothers, were caged separately according to genotype. Histologic and inflammatory status were assessed over time, along with changes in their respective microbiome compositions. Results Dysbiosis in Winnie mice was already established at 4 weeks of age, before histologic evidence of gut inflammatory changes, in which microbial communities diverged from that derived from their mothers. Furthermore, dysbiosis persisted until 12 weeks of age, with peak differences in microbiome composition observed between Winnie and WT mice at 8 weeks of age. The relative abundance of Bacteroidetes was greater in Winnie compared with WT mice. Verrucomicrobia was detected at the highest relative levels in 4-week-old Winnie mice; in particular, Akkermansia muciniphila was among the most abundant species found at 4 weeks of age. Conclusions Our results demonstrate that mutant genetic determinants involved in the complex regulation of intestinal homeostasis, such as that observed in Winnie mice, are able to promote early gut dysbiosis that is independent from maternal microbial transfer, including breastfeeding. Our data provide evidence for intestinal dysbiosis attributed to a Muc2-driven mucus defect that leads to colonic inflammation and may represent an important target for the design of future interventional studies., With the present study, we demonstrate that siblings with different genotypes but the same mother and fed by the same milk develop a specific genotype-dependent intestinal microbiota at 4 weeks of age; differences between microbial communities persist and consolidate with age.

Dendritic cells are the most important antigen-presenting cells that link the innate and acquired immune system. In our previous study, we identified that the upregulation of miR-369-3p suppresses the LPS-induced inflammatory response, reducing C/EBP-β, TNFα and IL-6 production. With the aim of gaining further insight into the biological function of miR-369-3p during acute inflammatory response, in the present study we identified novel gene targets of miR-369-3p and demonstrated the suppressive ability of these genes on the inflammatory dendritic cells. Bioinformatic analyses revealed that iNOS is a potential target of miR-369-3p. We demonstrated that the ectopic induction of miR-369-3p markedly reduced iNOS mRNA and protein as well as NO production. Moreover, we found that the upregulation of miR-369-3p decreased the release of TNFα, IL-6, IL-12, IL-1α, IL-1β in response to LPS, and increased the production of anti-inflammatory cytokines such as IL-10 and IL-1RA. In addition, LPS-induced nuclear translocation of NF-kB was inhibited by miR-369-3p. Levels of miR-369-3p were decreased in human inflamed regions of human intestine obtained from IBD patients. Our results provide novel additional information on miR-369-3p as a potential core of the signaling regulating the inflammatory response. These findings suggest that miR-369-3p should be considered as a potential target for the future development of new molecular therapeutic approaches.

Background: Adherence to a healthy diet has been reported to be essential for the primary prevention of colorectal cancer, through a reduction of tissue inflammation, a low concentration of circulating lipoproteins and lower levels of serum cholesterol. Since an altered expression of the fatty acids pattern has been demonstrated to be a crucial event in colorectal carcinogenesis, lipidomic analysis is considered able to identify early diagnostic and prognostic biomarkers of complex diseases such as colorectal cancer. Methods: cell membrane fatty acid profile and serum lipoproteins pattern were evaluated by gas chromatography and electrophoresis method respectively. Results: There is a close association between diet and lipidomic profile in colorectal cancer, both in pre-clinical and clinical studies. A modified serum lipoproteins pattern has been demonstrated to be predominant in intestinal tumors. Conclusions: The study of fatty acids profile in cell membrane and the evaluation of serum lipoproteins subfractions could be useful to have an integrate vision on the interactions between lipids and the pathogenesis of colorectal cancer and to understand the mechanisms of action and the consequences of these interactions on human health status. (www.actabiomedica.it)

Multiple cytokines produced by immune cells induce remodeling and aid in maintaining bone homeostasis through differentiation of bone-forming osteoblasts and bone-resorbing osteoclasts. Here, we investigate bone remodeling controlled by the tumor necrosis factor (TNF) superfamily cytokine LIGHT. LIGHT-deficient mice (Tnfsf14-/- ) exhibit spine deformity and reduced femoral cancellous bone mass associated with an increase in the osteoclast number and a slight decrease of osteoblasts compared with WT mice. The effect of LIGHT in bone cells can be direct or indirect, mediated by both the low expression of the anti-osteoclastogenic osteoprotegerin (OPG) in B and T cells and reduced levels of the pro-osteoblastogenic Wnt10b in CD8+ T cells in Tnfsf14-/- mice. LIGHT stimulation increases OPG levels in B, CD8+ T, and osteoblastic cells, as well as Wnt10b expression in CD8+ T cells. The high bone mass in Light and T- and B-cell-deficient mice (Rag- /Tnfsf14- ) supports the cooperative role of the immune system in bone homeostasis. These results implicate LIGHT as a potential target in bone disease. © 2017 American Society for Bone and Mineral Research.

SCOPE The study aims to investigate the effects of fresh table grape consumption in healthy subjects on circulating levels of the most common human microRNAs (miRNAs). The regulatory network governed by these modulated miRNAs is also investigated. METHODS AND RESULTS Autumn Royal table grape, used in this study, is chosen for its high polyphenolic content and antioxidant properties. The study is a randomized controlled trial, in which 40 consecutive subjects are recruited on a voluntary basis and randomly assigned to two groups of the study, the control group, receiving only dietary recommendations and a grape group receiving a daily dose of 5 g of fresh table grape per kg of body weight for 21 days. All analyses are performed at baseline and after 21 days of dietary treatment. Circulating miRNAs levels are detected by Real-Time quantitative PCR (RT-qPCR) followed by bioinformatic functional analysis. The study identifies 20 circulating miRNAs differentially expressed in healthy subjects after grape intake, and in particular, 18 of 20 are down-regulated and 2 are up-regulated. CONCLUSION The dietary intake of table grape affects circulating miRNAs levels in healthy subjects, particularly the miRNAs related to pathways involved in counteracting cancer development, including gastrointestinal cancers.

Changes in the regulation of endocannabinoid production, together with an altered expression of their receptors are hallmarks of cancer, including colorectal cancer (CRC). Although several studies have been conducted to understand the biological role of the CB1 receptor in cancer, little is known about its involvement in the metastatic process of CRC. The aim of this study was to investigate the possible link between CB1 receptor expression and the presence of metastasis in patients with CRC, investigating the main signaling pathways elicited downstream of CB1 receptor in colon cancer. Fifty-nine consecutive patients, with histologically proven colorectal cancer, were enrolled in the study, of which 30 patients with synchronous metastasis, at first diagnosis and 29 without metastasis. A low expression of CB1 receptor were detected in primary tumor tissue of CRC patients with metastasis and consequently, we observed an alteration of CB1 receptor downstream signaling. These signaling routes were also altered in intestinal normal mucosa, suggesting that, normal mucosa surrounding the tumor provides a realistic picture of the molecules involved in tissue malignant transformation. These observations contribute to the idea that drugs able to induce CB1 receptor expression can be helpful in order to set new anticancer therapeutic strategies. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.

The administration of a ketogenic diet (KD) has been considered therapeutic in subjects with irritable bowel syndrome (IBS). This study aimed to investigate the molecular mechanisms by which a low-carbohydrate diet, such as KD, can improve gastrointestinal symptoms and functions in an animal model of IBS by evaluating possible changes in intestinal tissue expression of endocannabinoid receptors. In rats fed a KD, we detected a significant restoration of cell damage to the intestinal crypt base, a histological feature of IBS condition, and upregulation of CB1 and CB2 receptors. The diet also affected glucose metabolism and intestinal membrane permeability, with an overexpression of the glucose transporter GLUT1 and tight junction proteins in treated rats. The present data suggest that CB receptors represent one of the molecular pathways through which the KD works and support possible cannabinoid-mediated protection at the intestinal level in the IBS rats after dietary treatment.

In this study, we investigated the bone cell activity in patients with osteogenesis imperfecta (OI) treated and untreated with neridronate. We demonstrated the key role of Dickkopf-1 (DKK1), receptor activator of nuclear factor-κB ligand (RANKL), and tumor necrosis factor alpha (TNF-α) in regulating bone cell of untreated and treated OI subjects. These cytokines could represent new pharmacological targets for OI. Bisphosphonates are widely used in the treatment of children with osteogenesis imperfecta (OI) with the objective of reducing the risk of fractures. Although bisphosphonates increase bone mineral density in OI subjects, the effects on fracture incidence are conflicting. The aim of this study was to investigate the mechanisms underlying bone cell activity in subjects with mild untreated forms of OI and in a group of subjects with severe OI treated with cycles of intravenous neridronate. Sclerostin, DKK1, TNF-α, RANKL, osteoprotegerin (OPG), and bone turnover markers were quantified in serum of 18 OI patients (12 females, mean age 8.86 ± 3.90), 8 of which were receiving cyclic intravenous neridronate, and 21 sex- and age-matched controls. The effects on osteoblastogenesis and OPG expression of media conditioned by the serum of OI patients and anti-DKK1 neutralizing antibody were evaluated. Osteoclastogenesis was assessed in cultures from patients and controls. DKK1 and RANKL levels were significantly increased both in untreated and in treated OI subjects with respect to controls. The serum from patients with high DKK1 levels inhibited both osteoblast differentiation and OPG expression in vitro. High RANKL and low OPG messenger RNA (mRNA) levels were found in lymphomonocytes from patients. High amounts of TNF-α were expressed by monocytes, and an elevated percentage of circulating CD11b-CD51/CD61+ osteoclast precursors was observed in patients. Our study demonstrated the key role of DKK1, RANKL, and TNF-α in regulating bone cell activity of subjects with OI untreated and treated with bisphosphonates. These cytokines could represent new pharmacological targets for OI patients.

Colorectal cancer (CRC) is the third most common cancer worldwide. There is a need for the early diagnosis of CRC for a better prognostic outcome. It is, therefore, crucial to understand the CRC pathogenesis in all its aspects. In many cases, one of the main causes of cancer-related deaths is the presence of metastases. In this context, an often overlooked aspect is the metastatic tropism, since CRC, like other cancers, is more prone to metastasize some organs rather than others. Beyond the liver and lung, and differently from other types of cancers, a not usual site of CRC metastases is the bone. However, it may assume a crucial role in the development and the outcome of the disease. Therefore, this review aims to discuss the complex relations between bone markers and CRC pathogenesis, suggesting the use of these molecules as potential targets for therapeutic purposes. Different osteogenic molecules, some of whom are growth factors and are implicated in the different osteogenic pathways, have been proved to also be involved in CRC progression. Some of them are oncogenes, while others oncosuppressors, and in a future perspective, some of them may represent new potential CRC biomarkers.

Background/aim The expression of cannabinoid receptor-1 (CB1-R) seems to be modulated by bioactive natural components such as the flavonoid quercetin. The aim of this study was to determine in an animal model of induced-colon cancer, whether quercetin inhibits colon carcinogenesis through changes in the expression of CB1-R. Materials and methods C57BL/6J male mice were randomly assigned to standard diet or experimental diet supplemented with 0.5% quercetin. Azoxymethane (AOM) (10 mg/kg body weight) or saline solution (PBS) was intraperitoneally injected, once weekly for 6 weeks. Results The diet supplemented with quercetin induced CB1-R gene expression and protein, inhibiting the protein levels of STAT3 and p-STAT3 (both mediators of cell proliferation). Dietary quercetin also caused a significant increase in Bax/Bcl2 ratio protein expression. Conclusion The anti-proliferative and pro-apoptotic effects of quercetin in AOM-treated mice are mediated by induction of the protein and gene expression levels of CB1-R.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death in western countries. The major risk factors for HCC are hepatitis C or B viruses, alcohol and metabolic disorders. The increasing risk of HCC in patients with metabolic disorders (i.e. obesity, diabetes and non-alcoholic steatohepatitis/NASH) regardless of the presence of liver cirrhosis is becoming relevant. Nevertheless, molecular mechanisms linking these risk factors to liver oncogenesis are unclear. This review focuses on the pathogenic role of the lysophosphatidic acid (LPA) pathway in HCC, highlighting the implications of this bioactive phospholipid in liver cancer biology and metabolism and as potential therapeutic target.

Periodontal disease (PD), or periodontitis, is defined as a bacterially induced disease of the tooth-supporting (periodontal) tissues. It is characterized by inflammation and bone loss; therefore understanding how they are linked would help to address the most efficacious therapeutic approach. Bacterial infection is the primary etiology but is not sufficient to induce the disease initiation or progression. Indeed, bacteria-derived factors stimulate a local inflammatory reaction and activation of the innate immune system. The innate response involves the recognition of microbial components by host cells, and this event is mediated by toll-like receptors (TLRs) expressed by resident cells and leukocytes. Activation of these cells leads to the release of proinflammatory cytokines and recruitment of phagocytes and lymphocytes. Activation of T and B cells initiates the adaptive immunity with Th1 Th2 Th17 Treg response and antibodies production respectively. In this inflammatory scenario, cytokines involved in bone regulation and maintenance have considerable relevance because tissue destruction is believed to be the consequence of host inflammatory response to the bacterial challenge. In the present review, we summarize host factors including cell populations, cytokines, and mechanisms involved in the destruction of the supporting tissues of the tooth and discuss treatment perspectives based on this knowledge.

Background. The TNF superfamily member LIGHT, known to play a major role in T-cell homeostasis, has been reported in erosive bone disease associated with rheumatoid arthritis. Herein, we investigated whether LIGHT is implicated in the mechanisms leading to Multiple Myeloma (MM)-bone disease. Methods. Peripheral blood (PB) and bone marrow (BM) aspirates were obtained from 40 patients (23M/17F, median age: 64 years), newly diagnosed as having symptomatic MM with or without bone disease, smoldering MM (sMM) or M.G.U.S. Bone disease assessment was performed by skeleton x-Ray, and spine and pelvis NMR or CT. The control group included PB and BM aspirates from 15 patients with non-neoplastic disease without any skeletal involvement, and PB from 25 healthy-donors matching for age and sex with the MM group. Patients and controls gave their written informed consent to the study, approved by Ethical Committee of University Hospital of Bari, and performed according to Declaration of Helsinki. By means of flow cytometry, western blotting, and real-time PCR, LIGHT expression was assessed in freshly purified CD14+ monocytes, CD2+ T-cells and neutrophils from PB and BM aspirates of patients and controls. Osteoclasts (OCs) were obtained from unfractionated PBMC cultures treated or not with an anti-LIGHT neutralizing monoclonal antibody (mAb). Mature OCs were identified as multinucleated tartrate-resistant acid phosphatase (TRAP) positive cells. In cultures from BM mononuclear cells (BMNCs), the formation of CFU-F and CFU-OB was evaluated in the presence or absence of anti-LIGHT neutralizing mAb. CFU-F and CFU-OB were identified with alkaline phosphatase (ALP) or Von Kossa staining, respectively. Further, in CFU-F and CFU-OB cultures, the expression of OB differentiation markers was analyzed by real-time PCR. Results. We found overexpression of LIGHT on CD14+ monocytes, CD8+ T-cells and neutrophils of PB and BM from MM-bone disease patients, in whom LIGHT induced osteoclastogenesis and inhibited osteoblastogenesis, as we demonstrated by culture treatment with an anti-LIGHT antibody. Moreover, in cultures from healthy-donors, we found that LIGHT induced osteoclastogenesis in RANKL-dependent and –independent manners. In particular, in the presence of a sub-optimal RANKL concentration, LIGHT and RANKL showed synergic effects on osteoclast formation, associated to early and sustained activation of Akt, NFκB and JNK pathways. Otherwise in cultures of BM samples from patients without bone disease, LIGHT treatment inhibited the formation of CFU-F and CFU-OB, and the expression of osteoblastic markers such as collagen-I, osteocalcin and bone sialoprotein-II, supporting a LIGHT indirect inhibition of osteoblastogenesis, possibly and to some extent, through sclerostin expression by monocytes. Conclusions. Our findings, for the first time, provide evidence that LIGHT plays a role in MM-bone disease development by increasing osteoclastogenesis and decreasing osteoblastogenesis. Disclosures No relevant conflicts of interest to declare.

Introduction Multiple myeloma (MM)-bone disease occurs in 70% to 80% of patients at MM diagnosis, and up to 90% at relapse; skeletal related events cause high morbidity and mortality. MM-bone disease is mostly consisting of lytic lesions arising as a consequence of an unbalanced bone remodelling due to activation of osteoclasts (OCs), and inactivation of osteoblasts. Osteoclastogenesis may be under immunoregulation by T-cells through the production of receptor activator of NF-kB ligand (RANKL), that is the OC differentiating molecule. Aim By means of an in vitro osteoclastogenesis model derived from peripheral blood mononuclear cells (PBMCs) of patients with MM-lytic bone disease, we purposed to evaluate OC formation and T-cell RANKL expression at diagnosis, and in the setting of frontline therapy. Methods PB was taken by venipuncture from 18 patients (7 men and 11 women), aged from 63 to 84, diagnosed as having symptomatic MM by International Myeloma Working Group (IMWG) criteria. In all of them, lytic lesions were demonstrated by skeleton standard radiography, and in some cases by nuclear magnetic resonance (NMR) too. On the basis of patients’ age and fitness, initial standard therapy consisting of proteasome inhibitor (Bortezomib) associated with Melphalan and Prednisone (VMP) was administered for nine cycles. The therapy response was assessed according to IMWG criteria. The controls included PB collected from 20 healthy donors, matched for age and sex with the patients. Controls and patients gave their written informed consent to the study, that was approved by the local Ethical Committee and performed according to the Declaration of Helsinki. PB was taken from the patients at diagnosis, and following the fourth and the ninth VMP cycles, respectively. OCs were obtained from unfractionated PBMC cultures either stimulated or not with the exogenous pro-osteoclastogenic cytokines [macrophage-colony stimulating factor (M-CSF) and RANKL]. Mature OCs were identified as multinucleated tartrate-resistant acid phosphatase (TRAP) positive cells. Freshly isolated T-cells from patients’ and controls’ PBMCs were lysed and analyzed by Western Blotting to evaluate RANKL expression. Results Spontaneous osteoclastogenesis was demonstrated in the cultures derived from PBMCs isolated at diagnosis. With particular regard to the patients achieving a deep treatment response, at the end of the culture period we found that PBMCs formed few small-sized OCs, when cultured in the absence of M-CSF and RANKL. Moreover, fresh T-cells purified after four and nine VMP cycles expressed progressively lower RANKL levels than fresh T-cells purified at diagnosis. Otherwise the cultures derived from non-responsive patients’ PBMCs, collected during and after treatment respectively, showed in vitro spontaneous formation of numerous and large OCs, overlapping the results at diagnosis. Fresh T-cells purified during or after treatment expressed comparable or even higher RANKL levels respect to diagnosis. Conclusions These findings show that in vitro spontaneous osteoclastogenesis and T-cell RANKL expression may be correlated with the response to treatment in patients with MM-lytic bone disease. However, further studies will be necessary to confirm these data, and to better translate them from a biologic to a clinical point of view. Disclosures: No relevant conflicts of interest to declare.

// Giacomina Brunetti 1, * , Rita Rizzi 2, * , Angela Oranger 1 , Isabella Gigante 1 , Giorgio Mori 3 , Grazia Taurino 1 , Teresa Mongelli 1 , Graziana Colaianni 1 , Adriana Di Benedetto 1 , Roberto Tamma 1 , Giuseppe Ingravallo 4 , Anna Napoli 4 , Maria Felicia Faienza 5 , Anna Mestice 2 , Paola Curci 2 , Giorgina Specchia 2 , Silvia Colucci 1, * , Maria Grano 1, * 1 Department of Basic and Medical Sciences, Neurosciences and Sense Organs, section of Human Anatomy and Histology, University of Bari, Bari, Italy 2 Department of Emergency and Organ Transplantation, Section of Hematology with Transplantation, University of Bari, Bari, Italy 3 Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy 4 Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy 5 Department of Biomedical Sciences and Human Oncology, University of Bari, Bari, Italy * These authors contributed equally to this work Correspondence to: Brunetti Giacomina, e-mail: giacomina.brunetti@uniba.it Keywords: LIGHT/TNFSF14, multiple myeloma, bone disease, osteoclast, osteoblast Received: August 08, 2014 Accepted: October 23, 2014 Published: November 12, 2014 ABSTRACT LIGHT, a TNF superfamily member, is involved in T-cell homeostasis and erosive bone disease associated with rheumatoid arthritis. Herein, we investigated whether LIGHT has a role in Multiple Myeloma (MM)-bone disease. We found that LIGHT was overproduced by CD14+ monocytes, CD8+ T-cells and neutrophils of peripheral blood and bone marrow (BM) from MM-bone disease patients. We also found that LIGHT induced osteoclastogenesis and inhibited osteoblastogenesis. In cultures from healthy-donors, LIGHT induced osteoclastogenesis in RANKL-dependent and -independent manners. In the presence of a sub-optimal RANKL concentration, LIGHT and RANKL synergically stimulated osteoclast formation, through the phosphorylation of Akt, NFκB and JNK pathways. In cultures of BM samples from patients with bone disease, LIGHT inhibited the formation of CFU-F and CFU-OB as well as the expression of osteoblastic markers including collagen-I, osteocalcin and bone sialoprotein-II. LIGHT indirectly inhibited osteoblastogenesis in part through sclerostin expressed by monocytes. In conclusion, our findings for the first time provide evidence for a role of LIGHT in MM-bone disease development.