The extract based on the Kampo formula daikenchuto (Da Jian Zhong Tang) induces Bdnf expression and has neurotrophic effects in cultured cortical neurons.

Reductions in brain-derived neurotrophic factor (BDNF) expression levels have been reported in the brains of patients with neurological disorders such as Alzheimer's disease. Therefore, upregulating BDNF and preventing its decline in the diseased brain could help ameliorate neurological dysfunctions. Accordingly, we sought to discover agents that increase Bdnf expression in neurons. Here, we screened a library of 42 Kampo extracts to identify those with the ability to induce Bdnf expression in cultured cortical neurons. Among the active extracts identified in the screen, we focused on the extract based on the Kampo formula daikenchuto. The extract of daikenchuto in the library used in this study was prepared using the mixture of Zingiberis Rhizoma Processum (ZIN), Zanthoxyli Piperiti Pericarpium (ZAN), and Ginseng Radix (GIN) without Koi. In this study, we defined DKT as the mixture of ZIN, ZAN, and GIN without Koi (DKT extract means the extract prepared from the mixture of ZIN, ZAN, and GIN without Koi). DKT extract significantly increased endogenous Bdnf expression by mediated, at least in part, via Ca2+ signaling involving L-type voltage-dependent Ca2+ channels in cultured cortical neurons. Furthermore, DKT extract significantly improved the survival of cultured cortical neurons and increased neurite complexity in immature neurons. Taken together, our findings suggest that DKT extract induces Bdnf expression and has a neurotrophic effect in neurons. Because BDNF inducers are expected to have therapeutic potential for neurological disorders, re-positioning of Kampo formulations such as daikenchuto may lead to clinical application in diseases associated with reduced BDNF in the brain.

Impact of Goreisan components on rat mesenteric collecting lymphatic vessel pumping.

BACKGROUND: Goreisan is a traditional herbal formulation with diuretic properties tested as a clinical therapeutic to alleviate lymphedema in Japan. The present study aimed to determine how Goreisan and its five different components affect lymphatic pump function. METHODS: Mesenteric collecting lymphatics were isolated from anesthetized Sprague-Dawley rats and mounted on resistance-matched glass micropipettes in a 37°C physiological salt solution bath for studies. Diameter was continuously measured to obtain the following lymphatic pump parameters: contraction frequency (CF), end diastolic diameter (EDD), and end systolic diameter (ESD), contraction amplitude (AMP), ejection fraction (EF), and fractional pump flow (FPF). Goreisan and each of its components (Cinnamomi Cortex, Atractylodis Rhizoma, Alismatis Rhizoma, Polyporus, and Poria) were applied to the bath at concentrations of 1-30 µg/mL. RESULTS: The results show that while Goreisan causes no significant changes to lymphatic pumping, Alismatis Rhizoma and Polyporus each significantly reduce CF and FPF. In addition, rats that received oral administration of Goreisan and Alismatis Rhizoma for 1 week had elevated expression of VEGFR-3 in their mesenteric collecting lymphatics. CONCLUSIONS: Collectively, the results suggest that some components of Goreisan have a direct, rapid impact on lymphatic pumping. These findings provide new insights but also raise new questions about the therapeutic potential of Goreisan in patients with secondary lymphedema.

Kampo Formula-Pattern Models: The Development of 13 New Clinically Useful Standard Abdominal Pattern Models in the Fukushin Simulator.

Aim: In Kampo medicine, there exists an important system of diagnosis called Fukushin, or abdominal diagnosis or palpation. By applying pressure to the abdomen of the patient, the physician can gain important information on the patient's physical state and use those indications to choose a suitable Kampo formulation. We have previously developed a Fukushin simulator, a teaching tool that reproduces the important abdominal patterns that doctors will encounter in clinical practice and that has received favourable feedback for students and practitioners. In order to make diagnosis and prescription easier, it is desirable to have matched formula-pattern pairings. The present study aims to develop such pairings. Methods: With the previously developed models as a foundation, in the present study the production team (two members) used materials such as urethane foam and silicone rubber to build an additional 13 standard abdominal pattern models matched to Kampo herbal formulas commonly used by practitioners in Japan. Subsequently, the evaluation team (the remaining 10 authors) investigated the viability of these models. Results: The evaluation team determined that abdominal pattern models matched to the following typical Kampo formulas were created successfully: Dai-saiko-To (), Dai-joki-To (), Shigyaku-San (), Saiko-ka-ryukotsu-borei-To (), Keishi-bukuryo-Gan (), Hachimi-jio-Gan (), Hange-shashin-To (), Sho-saiko-To (), Hochu-ekki-To (), Sho-kenchu-To (), Toki-shakuyaku-San (), Ninjin-To (), and Dai-kenchu-To (). Conclusion: We suggest that these new formula-pattern models can make an important contribution to the standardization of abdominal diagnosis and prescription and to Kampo education.

Immunostimulatory properties of heat-resistant RNA in a decoction of Glycyrrhizae Radix.

Research on the bioactive components of herbal medicines have been conducted mainly on the secondary metabolites of herbal plants. Accordingly, limited information is available on primary metabolites (carbohydrates, amino acids, lipids, and nucleic acids) and their biological effects. Here, we focused on the heat-resistant RNA of a decoction of Glycyrrhizae Radix and showed its immunostimulatory effects. The RNA activated NF-κB/AP-1 and induced TNF-α production in murine macrophages. Further analysis revealed that the RNA was around 90 nucleotides long. RNA sequencing (RNA-Seq) by next generation sequencing (NGS) showed that approximately 30% of the NGS reads were mapped to the genome of Glycyrrhiza uralensis, which is plant material of Glycyrrhizae Radix. Further analysis of the other 70% of reads indicated that the RNA contained RNA sequences that could be mapped to various microorganisms. Together, these results propose nucleic acids as a new research field in the bioactive components of herbal medicines.

Corrigendum to "Suppression of Dynamical Network Biomarker Signals at the Predisease State (Mibyou) before Metabolic Syndrome in Mice by a Traditional Japanese Medicine (Kampo Formula) Bofutsushosan".

[This corrects the article DOI: 10.1155/2020/9129134.].

Suppression of Dynamical Network Biomarker Signals at the Predisease State (Mibyou) before Metabolic Syndrome in Mice by a Traditional Japanese Medicine (Kampo Formula) Bofutsushosan.

Due to the increasing incidence of metabolic syndrome, the development of new therapeutic strategies is urgently required. One promising approach is to focus on the predisease state (so-called Mibyou in traditional Japanese medicine) before metabolic syndrome as a preemptive medical target. We recently succeeded in detecting a predisease state before metabolic syndrome using a mathematical theory called the dynamical network biomarker (DNB) theory. The detected predisease state was characterized by 147 DNB genes among a total of 24,217 genes in TSOD (Tsumura-Suzuki Obese Diabetes) mice, a well-accepted model of metabolic syndrome, at 5 weeks of age. The timing of the predisease state was much earlier than the onset of metabolic syndrome in TSOD mice reported to be at approximately 8-12 weeks of age. In the present study, we investigated whether the predisease state in TSOD mice can be inhibited by the oral administration of a Kampo formula, bofutsushosan (BTS), which is usually used to treat obese patients with metabolic syndrome in Japan, from 3 to 7 weeks of age. We found the comprehensive suppression of the early warning signals of the DNB genes by BTS at 5 weeks of age and later. Specifically, the standard deviations of 134 genes among the 147 DNB genes decreased at 5 weeks of age as compared to the nontreatment control group, and 80 of them showed more than 50% reduction. In addition, at 7 weeks of age, the body weight and blood glucose level were significantly lower in the BTS-treated group than in the nontreatment control group. The results of our study suggest a novel mechanism of BTS; it suppressed fluctuations of the DNB genes at the predisease state before metabolic syndrome and thus prevented the subsequent transition to metabolic syndrome. In conclusion, this study demonstrated the preventive and preemptive effects of a Kampo formula on Mibyou before metabolic syndrome for the first time based on scientific evaluation.

Immunostimulatory effects of cell wall-based nanoparticles in boiled Glycyrrhizae radix water extracts involves TLR4.

A number of immunostimulant effects of herbal medicines have been reported; however, the underlying mechanisms of their immunostimulatory effects have not been elucidated in detail. Our previous study showed that sugar-based nanoparticles derived from cell walls acted as the immunostimulatory component of boiled Glycyrrhizae radix water extracts. Therefore, the aim of the present study was to clarify the molecular mechanisms by which these cell wall-based nanoparticles functioned as immunostimulants. Mouse macrophage RAW-blue cells were stimulated by these nanoparticles and several immunological effects were investigated. When phosphorylation of nuclear factor-κB (NF)-κB p65 subunit was increased, the expression of the inflammatory cytokines interleukin-6 and tumor necrosis factor-α were induced via NF-κB. On the other hand, Toll-like receptor 4 recognizes cell wall components of bacteria and fungi. In the present study, it was also shown that these cell wall-based nanoparticles serve an immunostimulatory role as ligands of Toll-like receptor 4 by RNA interference experiments. The results of the present study suggested that the signaling pathway of nanoparticles obtained from boiled Glycyrrhizae radix water extracts, at least partially involved TLR4 and downstream signaling from this receptor, resulting in the immunostimulatory effects of these nanoparticles in RAW-blue cells.

[Pharmacological Effects of Yokukansankachimpihange on Urinary Catecholamine in Restraint-stressed Mice].

Herbal medicines, acupuncture and moxibustion are often used for unidentified complaints. It is well known that catecholamine secreted by the sympatho-adrenal medullary system primarily functions to increase cardiac output and raise glucose levels in the blood during acute stress. In the present study, the effects of yokukansankachimpihange (YKSKCH, a Kampo medicine) on urinary catecholamine in mice that were repeatedly stressed by restraining were examined. Restraint stress (240 min/d×3 d×3 cycles, daytime: 12:00-16:00) induced a marked increase in noradrenaline (NA) and adrenaline (A) levels in the urine. Oral administration of YKSKCH (750 mg/kg of body weight) significantly inhibited the increase in urinary NA and A levels in mice after repeated restraint stress. In addition, the NA/dopamine (physical stress) and A/dopamine (mental stress) ratios were lower in the 750 mg/kg YKSKCH-treated group than in the control group. The tail suspension test was also performed and locomotor activity was investigated. Oral administration of YKSKCH at 750 mg/kg significantly reduced the immobility time, which was longer in mice after repeated restraint stress. Furthermore, oral administration of YKSKCH at 750 mg/kg increased locomotor activity, which was lower in mice after repeated restraint stress. These results suggest that YKSKCH has positive effects on mental and physical stress after repeated restraint stress, without reducing locomotor activity.

Screening inducers of neuronal BDNF gene transcription using primary cortical cell cultures from BDNF-luciferase transgenic mice.

Brain-derived neurotrophic factor (BDNF) is a key player in synaptic plasticity, and consequently, learning and memory. Because of its fundamental role in numerous neurological functions in the central nervous system, BDNF has utility as a biomarker and drug target for neurodegenerative and neuropsychiatric disorders. Here, we generated a screening assay to mine inducers of Bdnf transcription in neuronal cells, using primary cultures of cortical cells prepared from a transgenic mouse strain, specifically, Bdnf-Luciferase transgenic (Bdnf-Luc) mice. We identified several active extracts from a library consisting of 120 herbal extracts. In particular, we focused on an active extract prepared from Ginseng Radix (GIN), and found that GIN activated endogenous Bdnf expression via cAMP-response element-binding protein-dependent transcription. Taken together, our current screening assay can be used for validating herbal extracts, food-derived agents, and chemical compounds for their ability to induce Bdnf expression in neurons. This method will be beneficial for screening of candidate drugs for ameliorating symptoms of neurological diseases associated with reduced Bdnf expression in the brain, as well as candidate inhibitors of aging-related cognitive decline.

Identifying pre-disease signals before metabolic syndrome in mice by dynamical network biomarkers.

The establishment of new therapeutic strategies for metabolic syndrome is urgently needed because metabolic syndrome, which is characterized by several disorders, such as hypertension, increases the risk of lifestyle-related diseases. One approach is to focus on the pre-disease state, a state with high susceptibility before the disease onset, which is considered as the best period for preventive treatment. In order to detect the pre-disease state, we recently proposed mathematical theory called the dynamical network biomarker (DNB) theory based on the critical transition paradigm. Here, we investigated time-course gene expression profiles of a mouse model of metabolic syndrome using 64 whole-genome microarrays based on the DNB theory, and showed the detection of a pre-disease state before metabolic syndrome defined by characteristic behavior of 147 DNB genes. The results of our study demonstrating the existence of a notable pre-disease state before metabolic syndrome may help to design novel and effective therapeutic strategies for preventing metabolic syndrome, enabling just-in-time preemptive interventions.

Correction to: Impact of different post-harvest processing methods on the chemical compositions of peony root.

The article Impact of different post­harvest processing methods on the chemical compositions of peony root.

Shikonin induces an anti­tumor effect on murine mammary cancer via p38­dependent apoptosis.

Breast cancer is the most common malignancy in women. Apoptosis is important for tumor suppression and may delay cancer progression. It was found that shikonin induced apoptosis in 4T1 murine mammary cancer cells and MDA­MB­231 human breast cancer cells in vitro. Total p38 and c­Jun N­terminal kinase (JNK) levels were maintained in 4T1 cells, and p38 phosphorylation, but not JNK phosphorylation, was significantly increased. Caspase­3/7 activity was detected, which suggested that the p38 pathway, but not the JNK signaling pathway, induced apoptosis in 4T1 cells. The anti­tumor effects of shikonin on orthotopic mouse models were also examined. On day 7 after inoculation of 4T1 cells into mice, tumor volumes in the shikonin­treated and the control groups began to differ. On day 13, tumors were weighed, and shikonin was revealed to suppress tumor growth in the orthotopic 4T1 model in vivo. In conclusion, shikonin is a potential anti­tumor drug for breast cancer.

Discovery of a sugar-based nanoparticle universally existing in boiling herbal water extracts and their immunostimulant effect.

Herbal medicine is mainly prepared from boiling herbal water extracts. Many epoch-making immunosuppressant drugs, such as glycyrrhizic acid (old example) and FTY720 (current example), were developed from herbal secondary metabolites in the boiling water extract by partition with organic solvents. However, few immunostimulants have been discovered by this method. Instead of the usual method, we aimed to find a novel immunostimulant component by two unique methods in the research of herbal medicine: ultracentrifugation and electron microscopy. The immunostimulant was not a secondary metabolite, as expected, but the structure was a nanoparticle formed by a polysaccharide. In addition, we clarified the immune effect of the nanoparticle. Intake of the nanoparticle by phagocytosis resulted in immunostimulant effects by increasing the genes and proteins of inflammatory cytokines in macrophage cells. The immunostimulant effects were inhibited by a phagocytosis inhibitor, cytochalasin D. To the best of our knowledge, this study is the first to describe the discovery of a nanoparticle in boiling herbal water extracts and its immunostimulant properties. This study will provide additional understanding of the efficacy of herbal medicine, in that the immunostimulant nanoparticle universally exists in boiling herbal water extracts. Thus, traditional herbal medicine may be an oldest known nanomedicine. Furthermore, this study suggests that the immunostimulant nanoparticle simply can be obtained from herbal medicine only by ultracentrifugation. We hope that this simple strategy will substantially contribute to drug development, including vaccine adjuvant, in the future.

Partial depletion of CD206-positive M2-like macrophages induces proliferation of beige progenitors and enhances browning after cold stimulation.

Beige adipocytes are an inducible form of thermogenic adipocytes that become interspersed within white adipose tissue (WAT) depots in response to cold exposure. Previous studies have shown that type 2 cytokines and M2 macrophages induce cold-induced browning in inguinal WAT (ingWAT) by producing catecholamines. Exactly how the conditional and partial depletion of CD206+ M2-like macrophages regulates the cold-induced browning of ingWAT, however, remains unknown. We examined the role of CD206+ M2-like macrophages in the cold-induced browning of WAT using genetically engineered CD206DTR mice, in which CD206+ M2-like macrophages were conditionally depleted. The partial depletion of CD206+ M2-like enhanced UCP1 expression in ingWAT, as shown by immunostaining, and also upregulated the expression of Ucp1 and other browning-related marker genes in ingWAT after cold exposure. A flow cytometry analysis showed that the partial depletion of CD206+ M2-like macrophages caused an increase in the number of beige progenitors in ingWAT in response to cold. Thus, we concluded that CD206+ M2-like macrophages inhibit the proliferation of beige progenitors and that the partial depletion of CD206+ M2-like macrophages releases this inhibition, thereby enhancing browning and insulin sensitivity.

Impact of different post-harvest processing methods on the chemical compositions of peony root.

The impact of key processing steps such as boiling, peeling, drying and storing on chemical compositions and morphologic features of the produced peony root was investigated in detail by applying 15 processing methods to fresh roots of Paeonia lactiflora and then monitoring contents of eight main components, as well as internal root color. The results showed that low temperature (4 °C) storage of fresh roots for approximately 1 month after harvest resulted in slightly increased and stable content of paeoniflorin, which might be due to suppression of enzymatic degradation. This storage also prevented roots from discoloring, facilitating production of favorable bright color roots. Boiling process triggered decomposition of polygalloylglucoses, thereby leading to a significant increase in contents of pentagalloylglucose and gallic acid. Peeling process resulted in a decrease of albiflorin and catechin contents. As a result, an optimized and practicable processing method ensuring high contents of the main active components in the produced root was developed.

Diosgenin-Rich Yam Extract Enhances Cognitive Function: A Placebo-Controlled, Randomized, Double-Blind, Crossover Study of Healthy Adults.

Diosgenin, a yam-derived compound, was found to facilitate the repair of axonal atrophy and synaptic degeneration and improve memory dysfunction in a transgenic mouse model of Alzheimer's disease (AD). It was also found to enhance neuronal excitation and memory function even in normal mice. We hypothesized that diosgenin, either isolated or in an extract, may represent a new category of cognitive enhancers with essential activities that morphologically and functionally reinforce neuronal networks. This study aimed to investigate the effects of a diosgenin-rich yam extract on cognitive enhancement in healthy volunteers. For this placebo-controlled, randomized, double-blind, crossover study, 28 healthy volunteers (age: 20-81 years) were recruited from Toyama Prefecture, Japan, and was randomly assigned to receive either a yam extract or placebo. Preliminary functional animal experiments indicated that an oil solvent mediated the most efficient distribution of diosgenin into the blood and brain after oral administration, and was a critical factor in the cognitive benefits. Therefore, test samples (placebo and yam extract) were prepared with olive oil and formulated as soft capsules. The intake period was 12 weeks, and a 6-week washout period separated the two crossover intake periods. The Japanese version of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) test was used for neurocognitive assessment, and the adverse effects were monitored through blood testing. Diosgenin-rich yam extract consumption for 12 weeks yielded significant increases in total RBANS score. Among the 12 individual standard cognitive subtests, diosgenin-rich yam extract use significantly improved the semantic fluency. No adverse effects were reported. The diosgenin-rich yam extract treatment appeared to safely enhance cognitive function in healthy adults.

Efficient Use of a Crude Drug/Herb Library Reveals Ephedra Herb As a Specific Antagonist for TH2-Specific Chemokine Receptors CCR3, CCR4, and CCR8.

Chemokine receptors CCR3 and CCR4 are preferentially expressed by TH2 cells, mast cells, and/or eosinophils, all of which are involved in the pathogenesis of allergic diseases. Therefore, CCR3 and CCR4 have long been highlighted as potent therapeutic targets for allergic diseases. Japanese traditional herbal medicine Kampo consists of multiple crude drugs/herbs, which further consist of numerous chemical substances. Recent studies have demonstrated that such chemical substances appear to promising sources in the development of novel therapeutic agents. Based on these findings, we hypothesize that Kampo-related crude drugs/herbs would contain chemical substances that inhibit the cell migration mediated by CCR3 and/or CCR4. To test this hypothesis, we screened 80 crude drugs/herbs to identify candidate substances using chemotaxis assay. Among those tested, Ephedra Herb inhibited the chemotaxis mediated by both CCR3 and CCR4, Cornus Fruit inhibited that mediated by CCR3, and Rhubarb inhibited that mediated by CCR4. Furthermore, Ephedra Herb specifically inhibited the chemotaxis mediated by not only CCR3 and CCR4 but CCR8, all of which are selectively expressed by TH2 cells. This result led us to speculate that ephedrine, a major component of Ephedra Herb, would play a central role in the inhibitory effects on the chemotaxis mediated by CCR3, CCR4, and CCR8. However, ephedrine exhibited little effects on the chemotaxis. Therefore, we fractionated Ephedra Herb into four subfractions and examined the inhibitory effects of each subfraction. As the results, ethyl acetate-insoluble fraction exhibited the inhibitory effects on chemotaxis and calcium mobilization mediated by CCR3 and CCR4 most significantly. In contrast, chloroform-soluble fraction exhibited a weak inhibitory effect on the chemotaxis mediated by CCR8. Furthermore, maoto, one of the Kampo formulations containing Ephedra Herb, exhibited the inhibitory effects on the chemotaxis mediated by CCR3, CCR4, and CCR8. Taken together, our data suggest that these crude drugs/herbs might be useful sources to develop new drugs targeting TH2-mediated allergic diseases.

Chrysin Inhibits Lymphangiogenesis in Vitro.

The induction of lymphangiogenesis is an important process to promote cancer growth and cancer metastasis via the lymphatic system. Identifying the compounds that can prevent lymphangiogenesis for cancer therapy is urgently required. Chrysin, 5,7-dihydroxyflavone, a natural flavone extracted from Thai propolis, was used to investigate the effect on the lymphangiogenesis process of TR-LE, rat lymphatic endothelial cells. In this study, maximal nontoxic doses of chrysin on TR-LE cells were selected by performing a proliferation assay. The process of lymphangiogenesis in vitro was determined by cord formation assay, adhesion assay and migration assay. Chrysin at a nontoxic dose (25 µM) significantly inhibited cord formation, cell adhesion and migration of TR-LE cells when compared with the control group. We also found that chrysin significantly induced vascular endothelial growth factor C (VEGF-C) mRNA expression and nitric oxide (NO) production in TR-LE cells which was involved in decreasing the cord formation of TR-LE cells. In conclusion, we report for the first time that chrysin inhibited the process of lymphangiogenesis in an in vitro model. This finding may prove to be a natural compound for anti-lymphangiogenesis that could be developed for use in cancer therapy.

Immune adjuvant effect of Juzentaihoto, a Japanese traditional herbal medicine, on tumor vaccine therapy in a mouse model.

Japanese traditional herbal medicine (Kampo) have been used to improve the general physical condition after surgery and to mitigate the side effects of radiation and chemotherapy in tumor patients. Juzentaihoto (JTT) consists of ten medical herbs, and is also called Shi-Quan-Da-Bu-Tang in Chinese herbal medicine. Among Kampo medicines, JTT has especially gained attention as a biological response modifier. Currently, clinical trials of various tumor vaccine therapies are being performed world-wide. However, tumor antigens that are inoculated as vaccines do not have high immunogenicity; thus, it is difficult to obtain an effective therapeutic effect. Thus, it is necessary to develop a tumor vaccine adjuvant that is more potent and very safe. In the present study, we examined the efficacy of JTT as an oral adjuvant when given together with tumor vaccines. As a result, JTT enhanced the phagocytic ability of OVA antigen and the presentation ability of OVA antigen in dendritic cells in vitro. Furthermore, tumor growth was markedly decreased, and the survival period was significantly prolonged in mice inoculated with mouse lymphoma, which is expressed with tumor model antigen. In conclusion, these findings suggest that JTT can be used with tumor vaccines as an immune adjuvant.

Role of chemokine CX3CL1 in progression of multiple myeloma via CX3CR1 in bone microenvironments.

Several chemokines/chemokine receptors such as CXCL12, CCL3, CXCR4 and CCR1 attract multiple myelomas to specific microenvironments. In the present study, we investigated whether the CX3CL1/CX3CR1 axis is involved in the interaction of the multiple myeloma cells with their microenvironment. The expression of CX3CR1 (also known as fractalkine) was detected in three of the seven human myeloma cell lines. CX3CL1-induced phosphorylation of Akt and ERK1/2 was detected in the CX3CR1-positive cell lines, but not in the CX3CR1-negative cell lines. In addition, CX3CL1-induced cell adhesion to fibronectin and vascular cell adhesion molecule-1 (VCAM-1) in the human myeloma RPMI-8226 cell line. We also investigated whether a relationship existed between myeloma cells and osteoclasts that may function via the CX3CL1/CX3CR1 axis. Conditioned medium from CX3CL1-stimulated RPMI-8226 cells drastically increased the osteoclast differentiation. Collectively, the results from the present study support the concept of the CX3CL1-mediated activation of the progression of the multiple myeloma via CX3CR1. Thus, CX3CR1 may represent a potential therapeutic target for the treatment of multiple myeloma in a bone microenvironment.