Infection-Induced Rhabdomyolysis in a Pregnant Woman with Undiagnosed Myotonic Dystrophy: A Case Report.

A 34-year-old nulliparous gravid female presented with acute bilateral pyelonephritis at 29 + 5 weeks gestation. The patient was relatively well until two weeks ago when a slight increase in amniotic fluid was noted. Further investigation revealed myoglobinuria and significantly elevated levels of creatine phosphokinase. The patient was subsequently diagnosed with rhabdomyolysis. Twelve hours after admission, the patient noted reduced fetal movements. A non-stress test revealed fetal bradycardia and non-reassuring variability in fetal heart rate. An emergency cesarean section was performed, and a "floppy" female child was delivered. Genetic testing revealed congenital myotonic dystrophy, and the mother was also diagnosed with myotonic dystrophy. Rhabdomyolysis has a very low incidence in pregnancy. Herein, we report a rare case of myotonic dystrophy with rhabdomyolysis in a gravid female with no history of myotonic dystrophy. Acute pyelonephritis is a causative agent of rhabdomyolysis that results in preterm birth.

Perinatal Outcomes and Neurodevelopment 1 Year after Birth in Discordant Twins According to Chorionicity.

Background and Objectives: This study aimed to compare maternal complications, perinatal outcomes, and neurodevelopment 1 year after the birth between concordant and discordant twins in monochorionic and dichorionic twins. Materials and Methods: This retrospective study included twin pregnancies delivered between 24 + 1 and 38 + 2 weeks of gestation between January 2011 and September 2019. Chorionicity was confirmed by ultrasonography and was categorized into monochorionic and dichorionic. Each was then divided into two groups (concordant and discordant) according to birth weight discordancy. Maternal complications and neonatal outcomes, including neurodevelopmental delays, were compared between the two groups. Results: A total of 298 pairs of twin pregnancies were enrolled, of which 58 (19.26%) women were pregnant with monochorionic diamniotic twins and 240 (80.54%) with dichorionic diamniotic twins. In both monochorionic and dichorionic twins, the discordant twins had a greater incidence of emergency deliveries because of iatrogenic causes than the concordant twins. Among dichorionic twins, discordant twins had lower birth weight rates and higher hospitalization rates and morbidities than concordant twins. Among monochorionic twins, discordant twins had a lower birth weight and higher neonatal mortality than concordant twins. The neonatal size was not a predictor of neurodevelopment in this group. Based on the logistic regression analysis, male sex, respiratory distress syndrome, and bronchopulmonary dysplasia were risk factors for the neurodevelopmental delay; birth weight discordancy was significant only in dichorionic twins. Conclusions: Perinatal outcomes in discordant twins may be poor, and neurodevelopment 1 year after birth was worse in discordant twins than in concordant twins. Discordancy in twins can be a risk factor for neurodevelopmental delay.

Korean-english Bilingual Children's Stress Cue Sensitivity and its Relationship with Reading in English.

Lexical stress plays a critical role in multisyllabic word reading in English. However, assignment of English lexical stress, which is neither fixed nor marked in writing, can pose significant challenges for English learners and has not been well-understood. The present study aims to fill the research gap by studying sensitivity to lexical stress cues and its contribution to their word reading performance among young English-language learners whose first language is Korean. The fundamental differences in prosodic systems between Korean and English provide theoretical significance of studying how bilingual children having no lexical stress in their first language process English lexical stress. This study focuses on two major cues to English lexical stress: morphological and orthographic cues. Findings revealed that the participants are sensitive to the two stress cues, with better performance with orthographic cues to stress assignment. However, no statistically significant correlations were found among variables on stress cue sensitivity with those on reading.

Acute Twin-to-Twin Transfusion Syndrome Resulting in Fetal Bradycardia and Neonatal Death: A Case Report.

In monochorionic twins with no evidence of chronic twin-to-twin transfusion syndrome or twin anemia-polycythemia sequence, a sudden onset of fetal transfusion syndrome after the second trimester of pregnancy is defined as acute twin-to-twin transfusion syndrome. Labor pain, change in the fetal position, and birth order are known risk factors for this condition, and the hemoglobin level of the donor twin is usually reported to be <12 g/dL. We report a recent case of acute twin-to-twin transfusion syndrome without effective labor pain causing cervical changes, resulting in fetal bradycardia and neonatal death after birth; however, the anemia of the donor twin was not as severe as has been reported previously in twin-to-twin transfusion syndrome cases.

The role of S100A4 for bone metastasis in prostate cancer cells.

BACKGROUND: Prostate cancers frequently metastasize to bone, where the best microenvironment for distant colonization is provided. Since osteotropic metastasis of prostate cancer is a critical determinant of patients' survival, searches for preventive measures are ongoing in the field. Therefore, it is important to dissect the mechanisms of each step of bone metastasis, including the epithelial-mesenchymal transition (EMT) and cross-talk between metastatic niches and cancer cells. METHODS: In this study, we established a highly bone-metastatic subline of human prostate cancer cells by selecting bone-homing population of PC3 cells after cardiac injection of eight-week-old male BALB/c-nude mice. Then we assessed the proliferation, EMT characteristics, and migration properties of the subline (mtPC3) cells in comparison with the parental PC3 cells. To investigate the role of S100A4, we performed gene knock-down by lentiviral transduction, or treated cells with recombinant S100A4 protein or a S100A4-neutralizing antibody. The effect of cancer cells on osteoclastogenesis was evaluated after treatment of pre-osteoclasts with conditioned medium (CM) from cancer cells. RESULTS: The mtPC3 cells secreted a markedly high level of S100A4 protein and showed elevated cell proliferation and mesenchymal properties. The increased proliferation and EMT traits of mtPC3 cells was inhibited by S100A4 knock-down, but was not affected by exogenous S100A4. Furthermore, S100A4 released from mtPC3 cells stimulated osteoclast development via the cell surface receptor RAGE. Down-regulation or neutralization of S100A4 in the CM of mtPC3 cells attenuated cancer-induced osteoclastogenesis. CONCLUSION: Altogether, our results suggest that intracellular S100A4 promotes cell proliferation and EMT characteristics in tumor cells, and that secreted S100A4 activates osteoclastogenesis, contributing to osteolytic bone metastasis. Thus, S100A4 upregulation in cancer cells highly metastatic to bone might be a key element in regulating bone metastasis.

Gα12 regulates osteoclastogenesis by modulating NFATc1 expression.

The G12 family of G protein alpha subunits has been shown to participate in the regulation of various physiological processes. However, the role of Gα12 in bone physiology has not been well described. Here, by micro-CT analysis, we discovered that Gα12-knockout mice have an osteopetrotic phenotype. Histological examination showed lower osteoclast number in femoral tissue of Gα12-knockout mice compared to wild-type mice. Additionally, in vitro osteoclastic differentiation of precursor cells with receptor activator of nuclear factor-κB ligand (RANKL) showed that Gα12 deficiency decreased the number of osteoclast generated and the bone resorption activity. The induction of nuclear factor of activated T-cell c1 (NFATc1), the key transcription factor of osteoclastogenesis, and the activation of RhoA by RANKL was also significantly suppressed by Gα12 deficiency. We further found that the RANKL induction of NFATc1 was not dependent on RhoA signalling, while osteoclast precursor migration and bone resorption required RhoA in the Gα12-mediated regulation of osteoclasts. Therefore, Gα12 plays a role in differentiation through NFATc1 and in cell migration and resorption activity through RhoA during osteoclastogenesis.

A novel role for flotillin-1 in H-Ras-regulated breast cancer aggressiveness.

Elevated expression and aberrant activation of Ras have been implicated in breast cancer aggressiveness. H-Ras, but not N-Ras, induces breast cell invasion. A crucial link between lipid rafts and H-Ras function has been suggested. This study sought to identify the lipid raft protein(s) responsible for H-Ras-induced tumorigenicity and invasiveness of breast cancer. We conducted a comparative proteomic analysis of lipid raft proteins from invasive MCF10A human breast epithelial cells engineered to express active H-Ras and non-invasive cells expressing active N-Ras. Here, we identified a lipid raft protein flotillin-1 as an important regulator of H-Ras activation and breast cell invasion. Flotillin-1 was required for epidermal growth factor-induced activation of H-Ras, but not that of N-Ras, in MDA-MB-231 triple-negative breast cancer (TNBC) cells. Flotillin-1 knockdown inhibited the invasiveness of MDA-MB-231 and Hs578T TNBC cells in vitro and in vivo. In xenograft mouse tumor models of these TNBC cell lines, we showed that flotillin-1 played a critical role in tumor growth. Using human breast cancer samples, we provided clinical evidence for the metastatic potential of flotillin-1. Membrane staining of flotillin-1 was positively correlated with metastatic spread (p = 0.013) and inversely correlated with patient disease-free survival rates (p = 0.005). Expression of flotillin-1 was associated with H-Ras in breast cancer, especially in TNBC (p < 0.001). Our findings provide insight into the molecular basis of Ras isoform-specific interplay with flotillin-1, leading to tumorigenicity and aggressiveness of breast cancer.

Tetraspanin 7 regulates sealing zone formation and the bone-resorbing activity of osteoclasts.

Tetraspanin family proteins regulate morphology, motility, fusion, and signaling in various cell types. We investigated the role of the tetraspanin 7 (Tspan7) isoform in the differentiation and function of osteoclasts. Tspan7 was up-regulated during osteoclastogenesis. When Tspan7 expression was reduced in primary precursor cells by siRNA-mediated gene knock-down, the generation of multinuclear osteoclasts was not affected. However, a striking cytoskeletal abnormality was observed: the formation of the podosome belt structure was inhibited and the microtubular network were disrupted by Tspan7 knock-down. Decreases in acetylated microtubules and levels of phosphorylated Src and Pyk2 in Tspan7 knock-down cells supported the involvement of Tspan7 in cytoskeletal rearrangement signaling in osteoclasts. This cytoskeletal defect interfered with sealing zone formation and subsequently the bone-resorbing activity of mature osteoclasts on dentin surfaces. Our results suggest that Tspan7 plays an important role in cytoskeletal organization required for the bone-resorbing function of osteoclasts by regulating signaling to Src, Pyk2, and microtubules.

Thermal therapeutic method for selective treatment of deep-lying tissue by combining laser and high-intensity focused ultrasound energy.

Photothermal therapy is performed by delivering laser radiation into the target lesion containing tissue chromophores so as to induce localized heating. For high treatment efficacy, the laser wavelength should be selected to maximize the absorption of incident laser radiation in the tissue chromophores. However, even with the optimal laser wavelength, both the absorption and the scattering of laser energy in tissue openly hamper treatment efficacy in deep-lying lesions. To overcome the limitation, we propose a dual thermal therapeutic method in which both laser and acoustic energies are transmitted to increase therapeutic depth while maintaining high target selectivity of photothermal therapy. Through skin-mimicking phantom experiments, it was verified that the two different energies are complementary in elevation of tissue temperature, and the treatment depth using laser radiation is increased along with acoustic energy.

SREBP2 restricts osteoclast differentiation and activity by regulating IRF7 and limits inflammatory bone erosion.

Osteoclasts are multinucleated bone-resorbing cells, and their formation is tightly regulated to prevent excessive bone loss. However, the mechanisms by which osteoclast formation is restricted remain incompletely determined. Here, we found that sterol regulatory element binding protein 2 (SREBP2) functions as a negative regulator of osteoclast formation and inflammatory bone loss. Cholesterols and SREBP2, a key transcription factor for cholesterol biosynthesis, increased in the late phase of osteoclastogenesis. The ablation of SREBP2 in myeloid cells resulted in increased in vivo and in vitro osteoclastogenesis, leading to low bone mass. Moreover, deletion of SREBP2 accelerated inflammatory bone destruction in murine inflammatory osteolysis and arthritis models. SREBP2-mediated regulation of osteoclastogenesis is independent of its canonical function in cholesterol biosynthesis but is mediated, in part, by its downstream target, interferon regulatory factor 7 (IRF7). Taken together, our study highlights a previously undescribed role of the SREBP2-IRF7 regulatory circuit as a negative feedback loop in osteoclast differentiation and represents a novel mechanism to restrain pathological bone destruction.

Impact of vaccination and the omicron variant on COVID-19 severity in pregnant women.

We compared the clinical course of pregnant women with coronavirus disease 2019 (COVID-19) before and after the emergence of the omicron variant and based on vaccination status. We retrospectively reviewed the electronic medical charts of 224 patients and 82 deliveries from November 1, 2020, to March 7, 2022; of these, 42% were diagnosed during the omicron dominance period. Disease severity and morbidity of COVID-19 were significantly decreased during the omicron era. The vaccination rates among the patients were higher after omicron emergence (31.9%) than before (6.9%). Overall, 4.1% and 25% of patients had severe symptoms, and 2.6% and 16.2% required oxygen therapy in the vaccination and non-vaccination groups, respectively. Overall, patients had a more favorable clinical course in the omicron era; moreover, vaccinated patients were better protected than non-vaccinated patients, indicating the importance of vaccination against COVID-19.

RANKL-responsive epigenetic mechanism reprograms macrophages into bone-resorbing osteoclasts.

Monocyte/macrophage lineage cells are highly plastic and can differentiate into various cells under different environmental stimuli. Bone-resorbing osteoclasts are derived from the monocyte/macrophage lineage in response to receptor activator of NF-κB ligand (RANKL). However, the epigenetic signature contributing to the fate commitment of monocyte/macrophage lineage differentiation into human osteoclasts is largely unknown. In this study, we identified RANKL-responsive human osteoclast-specific superenhancers (SEs) and SE-associated enhancer RNAs (SE-eRNAs) by integrating data obtained from ChIP-seq, ATAC-seq, nuclear RNA-seq and PRO-seq analyses. RANKL induced the formation of 200 SEs, which are large clusters of enhancers, while suppressing 148 SEs in macrophages. RANKL-responsive SEs were strongly correlated with genes in the osteoclastogenic program and were selectively increased in human osteoclasts but marginally presented in osteoblasts, CD4+ T cells, and CD34+ cells. In addition to the major transcription factors identified in osteoclasts, we found that BATF binding motifs were highly enriched in RANKL-responsive SEs. The depletion of BATF1/3 inhibited RANKL-induced osteoclast differentiation. Furthermore, we found increased chromatin accessibility in SE regions, where RNA polymerase II was significantly recruited to induce the extragenic transcription of SE-eRNAs, in human osteoclasts. Knocking down SE-eRNAs in the vicinity of the NFATc1 gene diminished the expression of NFATc1, a major regulator of osteoclasts, and osteoclast differentiation. Inhibiting BET proteins suppressed the formation of some RANKL-responsive SEs and NFATc1-associated SEs, and the expression of SE-eRNA:NFATc1. Moreover, SE-eRNA:NFATc1 was highly expressed in the synovial macrophages of rheumatoid arthritis patients exhibiting high-osteoclastogenic potential. Our genome-wide analysis revealed RANKL-inducible SEs and SE-eRNAs as osteoclast-specific signatures, which may contribute to the development of osteoclast-specific therapeutic interventions.

Regulation of Osteoclast Differentiation and Activity by Lipid Metabolism.

Bone is a dynamic tissue and is constantly being remodeled by bone cells. Metabolic reprogramming plays a critical role in the activation of these bone cells and skeletal metabolism, which fulfills the energy demand for bone remodeling. Among various metabolic pathways, the importance of lipid metabolism in bone cells has long been appreciated. More recent studies also establish the link between bone loss and lipid-altering conditions-such as atherosclerotic vascular disease, hyperlipidemia, and obesity-and uncover the detrimental effect of fat accumulation on skeletal homeostasis and increased risk of fracture. Targeting lipid metabolism with statin, a lipid-lowering drug, has been shown to improve bone density and quality in metabolic bone diseases. However, the molecular mechanisms of lipid-mediated regulation in osteoclasts are not completely understood. Thus, a better understanding of lipid metabolism in osteoclasts can be used to harness bone cell activity to treat pathological bone disorders. This review summarizes the recent developments of the contribution of lipid metabolism to the function and phenotype of osteoclasts.

Elimination of Nontargeted Photoacoustic Signals for Combined Photoacoustic and Ultrasound Imaging.

As a molecular imaging modality, photoacoustic (PA) imaging has been in the spotlight because it can provide an optical contrast image of physiological information and a relatively deep imaging depth. However, its sensitivity is limited despite the use of exogenous contrast agents due to the background PA signals generated from nontargeted absorbers, such as blood and boundaries between different biological tissues. In addition, clutter artifacts generated in both in-plane and out-of-plane imaging region degrade the sensitivity of PA imaging. We propose a method to eliminate the nontargeted PA signals. For this study, we used a dual-modal ultrasound (US)-PA contrast agent that is capable of generating both the backscattered US and PA signals in response to the transmitted US and irradiated light, respectively. The US images of the contrast agents are used to construct a masking image that contains the location information about the target site and is applied to the PA image acquired after contrast agent injection. In vitro and in vivo experimental results demonstrated that the masking image constructed using the US images makes it possible to completely remove nontargeted PA signals. The proposed method can be used to enhance the clear visualization of the target area in PA images.

Exosome-based photoacoustic imaging guided photodynamic and immunotherapy for the treatment of pancreatic cancer.

Exosomes, which are released from all cells and take part in cell-to-cell communication, have been utilized as drug delivery vehicles in many recent studies. Immunotherapy is an emerging technology which uses patients' innate immune systems. In immunotherapy, immune cells are stimulated through antibodies, the other immune cells and genetic modifications for the purposes of, for instance, cancer therapy. In this study, tumor-derived re-assembled exosome (R-Exo) was simultaneously utilized as both a drug delivery carrier and an immunostimulatory agent. A chlorin e6 photosensitizer was loaded into tumor-derived exosomes during exosomal re-assembly. After this modification, R-Exo retains its original average size and has the same membrane proteins, which allows for targeting of tumor cells. Chlorin e6-loaded R-Exo (Ce6-R-Exo) can be visualized by photoacoustic imaging and can efficiently generate reactive oxygen species inside tumor cells under laser irradiation. In addition, Ce6-R-Exo increased the release of cytokines from immune cells, which indicates that these modified exosomes can be used as an immunotherapeutic agent. In conclusion, we developed a novel strategy that enables photoacoustic imaging-guided photodynamic and immune-combination therapy for the treatment of cancer with tumor-derived Ce6-R-Exo.

Machine Learning-Based Three-Month Outcome Prediction in Acute Ischemic Stroke: A Single Cerebrovascular-Specialty Hospital Study in South Korea.

BACKGROUND: Functional outcomes after acute ischemic stroke are of great concern to patients and their families, as well as physicians and surgeons who make the clinical decisions. We developed machine learning (ML)-based functional outcome prediction models in acute ischemic stroke. METHODS: This retrospective study used a prospective cohort database. A total of 1066 patients with acute ischemic stroke between January 2019 and March 2021 were included. Variables such as demographic factors, stroke-related factors, laboratory findings, and comorbidities were utilized at the time of admission. Five ML algorithms were applied to predict a favorable functional outcome (modified Rankin Scale 0 or 1) at 3 months after stroke onset. RESULTS: Regularized logistic regression showed the best performance with an area under the receiver operating characteristic curve (AUC) of 0.86. Support vector machines represented the second-highest AUC of 0.85 with the highest F1-score of 0.86, and finally, all ML models applied achieved an AUC > 0.8. The National Institute of Health Stroke Scale at admission and age were consistently the top two important variables for generalized logistic regression, random forest, and extreme gradient boosting models. CONCLUSIONS: ML-based functional outcome prediction models for acute ischemic stroke were validated and proven to be readily applicable and useful.

Augmenting MNK1/2 activation by c-FMS proteolysis promotes osteoclastogenesis and arthritic bone erosion.

Osteoclasts are bone-resorbing cells that play an essential role in homeostatic bone remodeling and pathological bone erosion. Macrophage colony stimulating factor (M-CSF) is abundant in rheumatoid arthritis (RA). However, the role of M-CSF in arthritic bone erosion is not completely understood. Here, we show that M-CSF can promote osteoclastogenesis by triggering the proteolysis of c-FMS, a receptor for M-CSF, leading to the generation of FMS intracellular domain (FICD) fragments. Increased levels of FICD fragments positively regulated osteoclastogenesis but had no effect on inflammatory responses. Moreover, myeloid cell-specific FICD expression in mice resulted in significantly increased osteoclast-mediated bone resorption in an inflammatory arthritis model. The FICD formed a complex with DAP5, and the FICD/DAP5 axis promoted osteoclast differentiation by activating the MNK1/2/EIF4E pathway and enhancing NFATc1 protein expression. Moreover, targeting the MNK1/2 pathway diminished arthritic bone erosion. These results identified a novel role of c-FMS proteolysis in osteoclastogenesis and the pathogenesis of arthritic bone erosion.

Age-adjusted quick Sequential Organ Failure Assessment score for predicting mortality and disease severity in children with infection: a systematic review and meta-analysis.

We assessed the diagnostic accuracy of the age-adjusted quick Sequential Organ Failure Assessment score (qSOFA) for predicting mortality and disease severity in pediatric patients with suspected or confirmed infection. We conducted a systematic search of PubMed, EMBASE, the Cochrane Library, and Web of Science. Eleven studies with a total of 172,569 patients were included in the meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio of the age-adjusted qSOFA for predicting mortality and disease severity were 0.69 (95% confidence interval [CI] 0.53-0.81), 0.71 (95% CI 0.36-0.91), and 6.57 (95% CI 4.46-9.67), respectively. The area under the summary receiver-operating characteristic curve was 0.733. The pooled sensitivity and specificity for predicting mortality were 0.73 (95% CI 0.66-0.79) and 0.63 (95% CI 0.21-0.92), respectively. The pooled sensitivity and specificity for predicting disease severity were 0.73 (95% CI 0.21-0.97) and 0.72 (95% CI 0.11-0.98), respectively. The performance of the age-adjusted qSOFA for predicting mortality and disease severity was better in emergency department patients than in intensive care unit patients. The age-adjusted qSOFA has moderate predictive power and can help in rapidly identifying at-risk children, but its utility may be limited by its insufficient sensitivity.

NRF2 Is an Upstream Regulator of MYC-Mediated Osteoclastogenesis and Pathological Bone Erosion.

Osteoclasts are the sole bone-resorbing cells that play an essential role in homeostatic bone remodeling and pathogenic bone destruction such as inflammatory arthritis. Pharmacologically targeting osteoclasts has been a promising approach to alleviating bone disease, but there remains room for improvement in mitigating drug side effects and enhancing cell specificity. Recently, we demonstrated the crucial role of MYC and its downstream effectors in driving osteoclast differentiation. Despite these advances, upstream regulators of MYC have not been well defined. In this study, we identify nuclear factor erythroid 2-related factor 2 (NRF2), a transcription factor known to regulate the expression of phase II antioxidant enzymes, as a novel upstream regulator of MYC. NRF2 negatively regulates receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis through the ERK and p38 signaling-mediated suppression of MYC transcription. Furthermore, the ablation of MYC in osteoclasts reverses the enhanced osteoclast differentiation and activity in NRF2 deficiency in vivo and in vitro in addition to protecting NRF2-deficient mice from pathological bone loss in a murine model of inflammatory arthritis. Our findings indicate that this novel NRF2-MYC axis could be instrumental for the fine-tuning of osteoclast formation and provides additional ways in which osteoclasts could be therapeutically targeted to prevent pathological bone erosion.

A CTGF-RUNX2-RANKL Axis in Breast and Prostate Cancer Cells Promotes Tumor Progression in Bone.

Metastasis to bone is a frequent occurrence in patients with breast and prostate cancers and inevitably threatens the patient's quality of life and survival. Identification of cancer-derived mediators of bone metastasis and osteolysis may lead to novel therapeutic strategies. In this study, we established highly bone-metastatic PC3 prostate and MDA-MB-231 (MDA) breast cancer cell sublines by in vivo selection in mice. In bone-metastatic cancer cells, the expression and secretion of connective tissue growth factor (CTGF) were highly upregulated. CTGF knockdown in bone-metastatic cells decreased invasion activity and MMP expression. RUNX2 overexpression in the CTGF knockdown cells restored the invasion activity and MMP expression. In addition, CTGF increased RUNX2 protein stability by inducing its acetylation via p300 acetyl transferase. The integrin αvß3 receptor mediated these effects of CTGF. Furthermore, CTGF promoted RUNX2 recruitment to the RANKL promoter, resulting in increased RANKL production from the tumor cells and subsequent stimulation of osteoclastogenesis from precursor cells. In addition, animal model with injection of CTGF knocked-down prostate cancer cells into 6-week old BALB/c male mice showed reduced osteolytic lesions. More importantly, the expression levels of CTGF and RANKL showed a strong positive correlation in human primary breast tumor tissues and were higher in bone metastases than in other site metastases. These findings indicate that CTGF plays crucial roles for osteolytic bone metastasis both by enhancing invasiveness of tumor cells and by producing RANKL for osteoclastogenesis. Targeting CTGF may lead to the development of effective preventive and therapeutic strategies for osteolytic metastasis. © 2019 American Society for Bone and Mineral Research.