Research progress of targeted therapy regulating Th17/Treg balance in bone immune diseases.

Rheumatoid arthritis (RA) and postmenopausal osteoporosis (PMOP) are common bone-immune diseases. The imbalance between helper (Th17) and regulatory T cells (Tregs) produced during differentiation of CD4+ T cells plays a key regulatory role in bone remodelling disorders in RA and PMOP. However, the specific regulatory mechanism of this imbalance in bone remodelling in RA and PMOP has not been clarified. Identifying the regulatory mechanism underlying the Th17/Treg imbalance in RA and PMOP during bone remodelling represents a key factor in the research and development of new drugs for bone immune diseases. In this review, the potential roles of Th17, Treg, and Th17/Treg imbalance in regulating bone remodelling in RA and PMOP have been summarised, and the potential mechanisms by which probiotics, traditional Chinese medicine compounds, and monomers maintain bone remodelling by regulating the Th17/Treg balance are expounded. The maintenance of Th17/Treg balance could be considered as an therapeutic alternative for the treatment of RA and PMOP. This study also summarizes the advantages and disadvantages of conventional treatments and the quality of life and rehabilitation of patients with RA and PMOP. The findings presented her will provide a better understanding of the close relationship between bone immunity and bone remodelling in chronic bone diseases and new ideas for future research, prevention, and treatment of bone immune diseases.

The effect of immunomodulatory drugs on bone metabolism of patients with multiple myeloma.

INTRODUCTION: Immunomodulatory drugs (IMiDs) are widely used in the management of newly diagnosed and relapsed/refractory multiple myeloma patients. These agents show their potential effect on myeloma bone disease (MBD), including inhibition of osteoclasts activity and effects on osteoblasts differentiation. It is unclear whether these effects are direct, which may have an impact on bone formation markers when combined with proteasome inhibitors. AREAS COVERED: This review summarizes the available evidence on the role of IMiDs in microenvironment regulation and their potential effects on bone metabolism. The literature search methodology consisted of searching PubMed for basic and clinical trials using medical subject terms. Included articles were screened and evaluated by the coauthors of this review. EXPERT OPINION: As a therapeutic option, IMiDs directly affect preosteoblast/osteoclast differentiation. The combination of proteasome inhibitors may counteract the short-term up-regulation of osteogenic activity markers, and therefore intravenous zoledronic acid is recommended, however, obtaining a more significant myeloma response will have a long-term positive impact on myeloma bone disease.

Effect of Loratadine for Pegfilgrastim-Induced Bone Pain.

AIMS: Breast cancer patients on chemotherapy who receive pegfilgrastim to prevent neutropenia may experience severe bone pain as a side effect. Traditional treatment recommendations include nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids, and/or antihistamine use. However, little research was found comparing these interventions. The study aim was to address the gaps in literature and to explore the use of and perceived effectiveness of loratadine versus acetaminophen or NSAIDs in women with breast cancer treated with pegfilgrastim. This study also sought to understand how patients became aware of loratadine or other treatments for management of bone pain. DESIGN/METHODS: This cross-sectional study used survey methods to collect data from 66 adult female breast cancer patients receiving chemotherapy with pegfilgrastim. RESULTS: The incidence of bone pain was 45% (n = 30) in our sample, but more than half (n = 45; 69%) of the women took either acetaminophen, NSAIDs, or loratadine alone or in combination to prevent bone pain. All medication were rated as effective by patients, with acetaminophen slightly more effective than loratadine, and loratadine more effective than NSAIDs. CONCLUSIONS: Acetaminophen, NSAIDs, and loratadine are easily available and inexpensive. However, unlike acetaminophen and NSAIDs, loratadine is dosed once a day and well tolerated with minimal adverse effects. CLINICAL IMPLICATIONS: Randomized controlled trials are needed to adequately assess the effectiveness of all three medication options. Because little is known about optimal use of any of these medications for pegfilgrastim-induced bone pain, it is also important to identify the optimal time to initiate treatment and ideal treatment duration.

Opiate use after total hip arthroplasty for metastatic bone disease.

OBJECTIVES: To investigate post-operative opioid use following a total hip arthroplasty (THA) in metastatic bone disease (MBD) patients and identify factors associated with post-operative opioid use at 6 weeks and 90 days. BACKGROUND: MBD commonly affects the hip, and surgical intervention including THA may be indicated for pain relief or to improve function. Following THA, patients are often prescribed short courses of opioids for post-operative pain relief. No study has evaluated opiate use following THA in patients for MBD. METHODS: This was a retrospective review of patients using opioids preoperatively who underwent primary THA for MBD at two institutions between 2009 and 2022. Preoperative and post-operative opioid usages, respectively, at 6 weeks and 90 days were quantified through calculating daily morphine milligram equivalents (MMEs) and compared using the sign test. Factors associated with post-operative opioid use at 6 weeks and 90 days were compared using χ2 test or Fisher's exact test as appropriate. RESULTS: Nineteen THA and 11 THA with complex acetabular reconstruction were included. At 6 weeks, 26 (86.7 percent) patients were utilizing opiates, and at 90 days, 23 (76.7 percent) patients were utilizing opiates. There was a statistically significant difference between median daily preoperative MME compared to daily MME at 90 days (p < 0.001). The only statistically significant association with opioid use at 90 days was opioid use at 6 weeks. CONCLUSION: To our knowledge, this is the first paper evaluating post-operative opioid use following primary THA in MBD patients. After THA in the setting of MBD, patients exhibit decreased post-operative opioid use. Future studies with larger cohorts should be conducted to characterize post-operative opioid use following joint arthroplasty in MBD patients.

Nrf2: A promising therapeutic target in bone-related diseases.

Nuclear factor erythroid-2-related factor 2 (Nrf2) plays an important role in maintaining cellular homeostasis, as it suppresses cell damage caused by external stimuli by regulating the transcription of intracellular defense-related genes. Accumulating evidence has highlighted the crucial role of reduction-oxidation (REDOX) imbalance in the development of bone-related diseases. Nrf2, a transcription factor linked to nuclear factor-erythrocyte 2, plays a pivotal role in the regulation of oxidative stress and induction of antioxidant defenses. Therefore, further investigation of the mechanism and function of Nrf2 in bone-related diseases is essential. Considerable evidence suggests that increased nuclear transcription of Nrf2 in response to external stimuli promotes the expression of intracellular antioxidant-related genes, which in turn leads to the inhibition of bone remodeling imbalance, improved fracture recovery, reduced occurrence of osteoarthritis, and greater tumor resistance. Certain natural extracts can selectively target Nrf2, potentially offering therapeutic benefits for osteogenic arthropathy. In this article, the biological characteristics of Nrf2 are reviewed, the intricate interplay between Nrf2-regulated REDOX imbalance and bone-related diseases is explored, and the potential preventive and protective effects of natural products targeting Nrf2 in these diseases are elucidated. A comprehensive understanding of the role of Nrf2 in the development of bone-related diseases provides valuable insights into clinical interventions and can facilitate the discovery of novel Nrf2-targeting drugs.

Advances in microneedle-based therapy for bone disorders.

Bone-related disorders treatment is a serious public health concern, imposing a significant social and economic burden on patients and healthcare systems. Although conventional drug delivery systems have made advances in bone diseases prevention and management, the limited delivery efficiency and convoluted focal environment lead to inadequate drug absorption and lack of specificity to achieve the intended therapeutic impact. Microneedle-based therapy represents an extraordinarily safe and well-tolerable therapeutic approach for treating bone disorders, providing improved efficacy by breaking down the barriers and delivery of therapeutic components to the target sites with programable release profiles in a less invasive manner. Over the past decades, numerous significant achievements in the development of various types of drug-carried microneedles have been made to address the obstacles encountered in the bone-treating procedure, enabling the microneedle-based therapy to take an important step in practical applications. In this light, this review summarizes these remarkable researches in terms of microneedles types and drug delivery strategies, with the goal of demonstrating the benefits of exploiting microneedle-based therapy as a novel strategy for treating bone-related disorders. The remaining challenges and future perspectives are also discussed in the hope of inspiring more efficient and intelligent bone treatment strategies.

Palliative Treatment for the Management of Advanced Pelvic Hydatid Bone Disease.

Hydatid bone disease is a zoonotic parasitic infection that is caused primarily by the tapeworm Echinococcus granulosus, and it continues to be a major public health concern in pastoral regions. The reconstruction of limb function after limb salvage surgery remains a challenge for clinicians. The purpose of this study was to determine the clinical efficacy of palliative treatment of the management of advanced pelvic hydatid bone disease. From March 2005 to December 2018, medical records and images of patients with advanced pelvic hydatid bone disease treated with surgery combined with antiparasitic chemotherapy were evaluated retrospectively. The Enneking classification was applied to determine the location of the lesion, and the Musculoskeletal Tumor Society score system was used for outcome evaluation. Fifteen patients who met the criteria were included in this study, with a mean follow-up of 4.40 ± 1.76 years. All patients received treatment with surgery combined with antiparasitic chemotherapy. The mean number of surgical interventions per patient for pelvic cystic echinococcosis was 5.3 (range, 2-9 interventions per patient). Recurrence of pelvic hydatid bone disease occurred in 5 patients and was managed successfully through repeated debridement procedures. Palliative treatment with limb salvage surgery was an effective and practical approach to the management of advanced pelvic hydatid bone disease. Standard antiparasitic chemotherapy, which included albendazole at a dose of 10 mg/kg/day administered in two daily doses for 3 to 6 months, was also considered an essential part of the overall treatment strategy.

Layered Double Hydroxides: A Novel Promising 2D Nanomaterial for Bone Diseases Treatment.

Bone diseases including bone defects, bone infections, osteoarthritis, and bone tumors seriously affect life quality of the patient and bring serious economic burdens to social health management, for which the current clinical treatments bear dissatisfactory therapeutic effects. Biomaterial-based strategies have been widely applied in the treatment of orthopedic diseases but are still plagued by deficient bioreactivity. With the development of nanotechnology, layered double hydroxides (LDHs) with adjustable metal ion composition and alterable interlayer structure possessing charming physicochemical characteristics, versatile bioactive properties, and excellent drug loading and delivery capabilities arise widespread attention and have achieved considerable achievements for bone disease treatment in the last decade. However, to the authors' best knowledge, no review has comprehensively summarized the advances of LDHs in treating bone disease so far. Herein, the advantages of LDHs for orthopedic disorders treatment are outlined and the corresponding state-of-the-art achievements are summarized for the first time. The potential of LDHs-based nanocomposites for extended therapeutics for bone diseases is highlighted and perspectives for LDHs-based scaffold design are proposed for facilitated clinical translation.

Maresin1: A multifunctional regulator in inflammatory bone diseases.

Inflammation plays a crucial role in the physical response to danger signals, the elimination of toxic stimuli, and the restoration of homeostasis. However, dysregulated inflammatory responses lead to tissue damage, and chronic inflammation can disrupt osteogenic-osteoclastic homeostasis, ultimately leading to bone loss. Maresin1 (MaR1), a member of the specialized pro-resolving mediators (SPMs) family, has been found to possess significant anti-inflammatory, anti-allergic, pro-hemolytic, pro-healing, and pain-relieving properties. MaR1 is synthesized by macrophages (Mφs) and omega-3 fatty acids, and it may have the potential to promote bone homeostasis and treat inflammatory bone diseases. MaR1 has been found to stimulate osteoblast proliferation through leucine-rich repeat G protein-coupled receptor 6 (LGR6). It also activates Mφ phagocytosis and M2-type polarization, which helps to control the immune system. MaR1 can regulate T cells to exert anti-inflammatory effects and inhibit neutrophil infiltration and recruitment. In addition, MaR1 is involved in antioxidant signaling, including nuclear factor erythroid 2-related factor 2 (NRF2). It has also been found to promote the autophagic behavior of periodontal ligament stem cells, stimulate Mφs against pathogenic bacteria, and regulate tissue regeneration and repair. In summary, this review provides new information and a comprehensive overview of the critical roles of MaR1 in inflammatory bone diseases, indicating its potential as a therapeutic approach for managing skeletal metabolism and inflammatory bone diseases.

Targeting strategies for bone diseases: signaling pathways and clinical studies.

Since the proposal of Paul Ehrlich's magic bullet concept over 100 years ago, tremendous advances have occurred in targeted therapy. From the initial selective antibody, antitoxin to targeted drug delivery that emerged in the past decades, more precise therapeutic efficacy is realized in specific pathological sites of clinical diseases. As a highly pyknotic mineralized tissue with lessened blood flow, bone is characterized by a complex remodeling and homeostatic regulation mechanism, which makes drug therapy for skeletal diseases more challenging than other tissues. Bone-targeted therapy has been considered a promising therapeutic approach for handling such drawbacks. With the deepening understanding of bone biology, improvements in some established bone-targeted drugs and novel therapeutic targets for drugs and deliveries have emerged on the horizon. In this review, we provide a panoramic summary of recent advances in therapeutic strategies based on bone targeting. We highlight targeting strategies based on bone structure and remodeling biology. For bone-targeted therapeutic agents, in addition to improvements of the classic denosumab, romosozumab, and PTH1R ligands, potential regulation of the remodeling process targeting other key membrane expressions, cellular crosstalk, and gene expression, of all bone cells has been exploited. For bone-targeted drug delivery, different delivery strategies targeting bone matrix, bone marrow, and specific bone cells are summarized with a comparison between different targeting ligands. Ultimately, this review will summarize recent advances in the clinical translation of bone-targeted therapies and provide a perspective on the challenges for the application of bone-targeted therapy in the clinic and future trends in this area.

Extracellular adenosine signaling in bone health and disease.

Purinergic signaling is a key molecular pathway in the maintenance of bone health and regeneration. P1 receptor signaling, which is activated by extracellular adenosine, has emerged as a key metabolic pathway that regulates bone tissue formation, function, and homeostasis. Extracellular adenosine is mainly produced by ectonucleotidases, and alterations in the function of these enzymes or compromised adenosine generation can result in bone disorders, such as osteoporosis and impaired fracture healing. This mini review discusses the key role played by adenosine in bone health and how its alterations contribute to bone diseases, as well as potential therapeutic applications of exogenous adenosine to combat bone diseases like osteoporosis and injury.

Myeloma bone disease: pathogenesis and management in the era of new anti-myeloma agents.

INTRODUCTION: Multiple myeloma (MM) is a malignancy of plasma cells with characteristic bone disease. Despite recent great strides achieved in MM treatment owing to the implementation of new anti-MM agents, MM is still incurable and bone destruction remains a serious unmet issue in patients with MM. APPROACH: In this review, we will summarize and discuss the mechanisms of the formation of bone disease in MM and the available preclinical and clinical evidence on the treatment for MM bone disease. CONCLUSIONS: MM cells produce a variety of cytokines to stimulate receptor activator of nuclear factor-κB ligand-mediated osteoclastogenesis and suppress osteoblastic differentiation from bone marrow stromal cells, leading to extensive bone destruction with rapid loss of bone. MM cells alter the microenvironment through bone destruction where they colonize, which in turn favors tumor growth and survival, thereby forming a vicious cycle between tumor progression and bone destruction. Denosumab or zoledronic acid is currently recommended to be administered at the start of treatment in newly diagnosed patients with MM with bone disease. Proteasome inhibitors and the anti-CD38 monoclonal antibody daratumumab have been demonstrated to exert bone-modifying activity in responders. Besides their anti-tumor activity, the effects of new anti-MM agents on bone metabolism should be more precisely analyzed in patients with MM. Because prognosis in patients with MM has been significantly improved owing to the implementation of new agents, the therapeutic impact of bone-modifying agents should be re-estimated in the era of these new agents.

Targeting Agents in Biomaterial-Mediated Bone Regeneration.

Bone diseases are a global public concern that affect millions of people. Even though current treatments present high efficacy, they also show several side effects. In this sense, the development of biocompatible nanoparticles and macroscopic scaffolds has been shown to improve bone regeneration while diminishing side effects. In this review, we present a new trend in these materials, reporting several examples of materials that specifically recognize several agents of the bone microenvironment. Briefly, we provide a subtle introduction to the bone microenvironment. Then, the different targeting agents are exposed. Afterward, several examples of nanoparticles and scaffolds modified with these agents are shown. Finally, we provide some future perspectives and conclusions. Overall, this topic presents high potential to create promising translational strategies for the treatment of bone-related diseases. We expect this review to provide a comprehensive description of the incipient state-of-the-art of bone-targeting agents in bone regeneration.

Colocación de implantes en paciente con antecedentes de toma de bifosfonatos / Placement of implants in a patient with a history of bisphosphonates taken

El uso de bifosfonatos es un excelente tratamiento para pacientes con artritis reumatoide y enfermedades óseas, por ejemplo, osteoporosis. Se realiza un reporte de caso de paciente femenino, quien estuvo bajo consumo de este fármaco por prescripción de su médico para la prevención de artritis reumatoide postmenopausia. La paciente acude a consulta para la colocación de implantes en zona desdentada y comenta haber terminado el tratamiento de bifosfonatos hace un año. Se tomaron pruebas de diagnóstico y se realizó la colocación de implantes sin ninguna complicación. Sus citas de control fueron más frecuentes en cuatro meses, sobre todo por el detalle de consumo de bifosfonatos, pero en ninguna cita hubo algún detalle alarmante, la cicatrización iba en forma. Se dio de alta a la paciente después de sus citas periódicas y de asegurar su buena cicatrización a un implante bien situado (AU))

The use of bisphosphonates is an excellent treatment for patients with rheumatoid arthritis and bone diseases such as osteoporosis. Here is a case report of a female patient, who was under consumption of this drug by prescription of her doctor for the prevention of post-menopausal rheumatoid arthritis. The patient went to the consultation for the placement of implants in the edentulous area and comments having finished the bisphosphonate treatment one year ago. The diagnostic tests were taken, and the implant placement was performed well without any complications. The control appointments were more frequent in four months, especially due to the detail of bisphosphonate consumption, but in no appointment, there were any alarming details, the healing was in good shape. The patient discharged after her regular appointments and to ensure that she was healing well and that implant was well placed (AU)

Management of bone diseases: looking at scaffold-based strategies for drug delivery.

The bone tissue can regenerate itself completely and continuously; however, large-scale bone defects may overpower this self-regenerative process. Furthermore, the aging population, the increment in obesity incidence, and the sedentary lifestyles are serious risk factors for bone diseases' development which are associated with the self-regenerative process's failure, high morbidity, and mortality rates. Thus, there is an ever-growing need for strategic approaches targeting bone replacement, its remodelling, and its regeneration. Bone scaffolds have successfully been used as synthetic bone grafts for many years, yet recent bone tissue engineering strategies attempt to explore their multifunctionality by investigating them as drug delivery systems. Bone diseases' treatments can be substantially difficult due to the avascular nature of the surrounding cartilage; thus, targeted drug delivery to the bone can be advantageous: it provides local high drug concentrations and minimizes adverse effects while securing a space for new, healthy tissue growth. Despite the promising scientific progress, studies underlining bone scaffolds' use as local drug delivery systems are not abundant. Hence, this work reviews bone scaffolds' therapeutic interest for local drug delivery in five distinct bone disorders-osteomyelitis, osteoporosis, osteoarthritis, osteosarcoma, and cancer bone metastasis. Additionally, it presents the challenges of this possible therapeutic approach and its future perspectives. Albeit bone scaffolds present therapeutic benefits by acting as drug delivery systems, further pre-clinical and clinical assessments are needed to strengthen their understanding and enable research evidence translation into clinical practice. The mismatch between scientific evolution and regulatory frameworks remains one of the major future challenges.

Long-term bone outcomes in Italian patients with Gaucher disease type 1 or type 3 treated with imiglucerase: A sub-study from the International Collaborative Gaucher Group (ICGG) Gaucher Registry.

BACKGROUND: Gaucher disease (GD) is a lysosomal storage disorder. We evaluated the "real-world" effectiveness of first-line imiglucerase on long-term bone outcomes in Italian patients in the International Collaborative Gaucher Group (ICGG) Gaucher Registry. METHODS: Patients treated with imiglucerase for ≥2 years and with bone assessments at baseline and during follow-up were selected. Data on bone pain, bone crises, marrow infiltration, avascular necrosis, infarction, lytic lesions, Erlenmeyer flask deformity, bone fractures, mineral density, and imiglucerase dosage were evaluated. RESULTS: Data on bone manifestations were available for 73 of 229 patients (31.9 %). Bone crises frequency decreased significantly from baseline to the most recent follow-up (p < 0.001), with some improvement observed in bone pain prevalence. Bone pain and bone crises prevalence decreased significantly from baseline at 2 to <4 and 4 to <6 years (all p < 0.05). A low median (25th, 75th percentile) baseline imiglucerase dosage was identified in patients reporting bone pain or bone crises (15.0 [13.7, 30.0] and 22.8 [17.5, 36.0] U/kg once every 2 weeks, respectively). CONCLUSION: Our study suggests that the management of GD in Italy, with regards to imiglucerase dosage, is suboptimal and confirms the need for clinicians to monitor and correctly treat bone disease according to best practice guidelines.

The use of bone-modifying agents in multiple myeloma.

Multiple myeloma is a hematological neoplasm characterized by abnormal proliferation of plasma cells in the bone marrow and is usually associated with increased bone pain and skeletal-related events such as pathological fracture and/or spinal cord compression. Myeloma bone disease results in changes in the bone-marrow microenvironment evidenced by increased osteoclastic activity and/or decreased osteoblastic activity, which negatively affect quality of life. Treatment of myeloma bone disease includes bisphosphonates or denosumab (bone-modifying agents). These agents do not induce the formation of new bone or repair existing bone damage, but they can decrease bone pain and the risk of pathological fracture. While these agents improve quality of life, it is not known whether they improve overall survival. This review focuses on different classes of bone-modifying agents, their mechanisms of action, time of initiation, duration of therapy, and potential survival benefits.

Aggressive Diffuse Intraosseous Hemangioma: Case Report / Hemangioma intraósseo difuso agressivo: Relato de caso

Abstract Vertebral hemangioma is a benign vascular tumor that is usually asymptomatic and is discovered incidentally on imaging. When symptomatic, the most frequent presentation occursinthe formofvague back painofinsidiousonset and,inrare cases, maybeassociated with root or spinal compression, causing sensory and motor deficits. The authors report the case of a 33-year-old man, previously healthy, with a diagnosis of thoracic spine hemangio-ma at multiple levels, in the sternum, in the scapula and in the costal arches; all lesions were symptomatic,and surgicalinterventionwas required; oneof thelesionsatthe thoracicspine level evolved with spinal compression and acute neurological deficit, requiring urgent surgical intervention. Intraosseoushemangiomas represent<1%ofall bonetumors, having few reports of multifocal presentation in the axial and appendicular skeleton. In the literature review, no other case of aggressive multifocal intraosseous hemangioma with this presentation was found, including associated neurological symptoms in the same case.

Resumo O hemangioma vertebral, um tumor vascular benigno, geralmente é assintomático e descoberto incidentalmente em exames de imagem. Quando sintomático, a apresentação mais frequente ocorre sob a forma de dorsalgia vaga de início insidioso e, em raros casos, pode estar associadoa compressão radicularoumedular, causando déficit sensitivo emotor. Osautores relatamocasodeumhomemde33anos, previamentehígido, com diagnósticos de hemangioma na coluna torácica em múltiplos níveis, no esterno, na escápula e nos arcos costais; todas as lesões eram sintomáticas e houve necessidade de intervenção cirúrgica, sendo que uma das lesões ao nível da coluna torácica evoluiu com compressão medular e déficit neurológico agudo, com necessidade de intervenção cirúrgica de urgência. Os hemangiomas intraósseos representam<1% detodosostumores ósseos,eaapresentação multifocal no esqueleto axial e apendicular apresenta poucos relatos. Na revisão bibliográfica, não foi encontrado outro caso dehemangioma intraósseo multifocal agressivo com tal apresentação, inclusive com sintomas neurológicos associados em um mesmo caso.

Modulating glycosphingolipid metabolism and autophagy improves outcomes in pre-clinical models of myeloma bone disease.

Patients with multiple myeloma, an incurable malignancy of plasma cells, frequently develop osteolytic bone lesions that severely impact quality of life and clinical outcomes. Eliglustat, a U.S. Food and Drug Administration-approved glucosylceramide synthase inhibitor, reduced osteoclast-driven bone loss in preclinical in vivo models of myeloma. In combination with zoledronic acid, a bisphosphonate that treats myeloma bone disease, eliglustat provided further protection from bone loss. Autophagic degradation of TRAF3, a key step for osteoclast differentiation, was inhibited by eliglustat as evidenced by TRAF3 lysosomal and cytoplasmic accumulation. Eliglustat blocked autophagy by altering glycosphingolipid composition whilst restoration of missing glycosphingolipids rescued autophagy markers and TRAF3 degradation thus restoring osteoclastogenesis in bone marrow cells from myeloma patients. This work delineates both the mechanism by which glucosylceramide synthase inhibition prevents autophagic degradation of TRAF3 to reduce osteoclastogenesis as well as highlighting the clinical translational potential of eliglustat for the treatment of myeloma bone disease.