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In the process of bone metastasis, tumor cells spread to the bones to activate osteoclasts, which cause pathological bone resorption and destruction. Bisphosphonates (BPs) inhibit osteoclast activation to resorb bone, reducing bone pain and fracture. We previously developed a nanocomposite for potential localized treatment of bone metastasis by loading a BP compound, ibandronate, onto oxidized carbon nanohorns (OxCNHs), a next-generation drug carrier, using calcium phosphates (CaPs) as mediators to generate OxCNH-CaP-BP nanocomposites. The objective of the present study was to determine nanocomposite formation and biological properties of nanocomposites constructed from two BPs, zoledronate and pamidronate.

Carbon nanohorns (CNHs), a type of nanocarbon, have been studied for the application of drug delivery systems (DDSs) because they are easily functionalized, support bone regeneration, can be used to perform photohyperthermia, have low toxicity, and are easily phagocytosed by macrophages. To take advantage of these features of CNHs, we developed a DDS for the local treatment of bone metastasis by loading the antibone resorption drug ibandronate (IBN) onto CNHs. The poor adsorption of IBN onto CNHs due to the weak hydrophilic-hydrophobic interaction was overcome by using calcium phosphates (CaPs) as mediators. In the fabrication process, we used oxidized CNH (OxCNH), which is less hydrophobic, onto which IBN was coprecipitated with CaP from a labile supersaturated CaP solution. OxCNH-CaP-IBN composite nanoparticles exerted stronger cell-suppressive effects than OxCNH and IBN in both murine macrophages (RAW264.7 cells) and osteoclasts (differentiated from RAW264.7 cells). OxCNH-CaP-IBN composite nanoparticles were efficiently phagocytosed by macrophage cells, where they specifically accumulated in lysosomes. The stronger cell-suppressive effects were likely due to intracellular delivery of IBN, i.e., the release of IBN from OxCNH-CaP-IBN composite nanoparticles via dissociation of CaP in the acidic environment of lysosomes. Our findings suggest that OxCNH-CaP-IBN composite nanoparticles are potentially useful for the local treatment of metastatic bone destruction.

Cribriform carcinoma in lymph nodes (LNs) is associated with distant metastasis, recurrence, and survival in node-positive colorectal cancer (CRC) patients. However, the clinical significance of lymph node metastasis histology remains to investigate. A total of 318 consecutive CRC patients who underwent a colectomy or anterior resection between January 2011 and June 2016 were enrolled, of whom 119 (37.4 %) had LN metastasis (LNM). Based on the LNM histology, patients with LNM were categorized into four groups: the group with tubular-type in all LNs (tub), with cribriform in at least one LN (cri), with mucinous-type in all LNs (muc), and with poorly differentiated-type carcinoma in at least one LN (por). We investigated the association among these histological types with the survival of these patients. The prognosis was good in order of muc, tub, cri, and por in node-positive CRC patients. Stage II and stage III tub groups did not have significantly different over-all survival times, but not recurrence-free survival times. Multivariate analyses revealed that all tubular-type carcinoma in LNs was independent predictive factor for longer survival times, clinical complete response and possible metastasectomy Diagnosis of lymph node metastatic histology is an important factor for patient stratification in node-positive CRC.

When cancer metastasizes to bone, the resulting pain and functional disorders due to bone destruction adversely affect the patient's quality of life. We have developed a new cancer metastasis control system consisting of anticancer agents conjugated to carbon fibers (CFs), which are nonbiodegradable, carriers of a wide variety of molecules with extremely high affinity for bone. In the evaluation of cancer suppression effects on Walker 256 cancer cells, cisplatin (CDDP)-conjugated CFs (CF-CDDP) were found to be as effective in cancer suppression as CDDP. In the evaluation of the cancer suppression effects of local injection in the rat model of tibial cancer bone metastasis, similar cancer suppression was noted in the CF-CDDP group and CDDP group; however, blood Pt concentrations were significantly lower in the CF-CDDP group. Experiments with CDDP and CF-CDDP injected into bone actually destroyed by cancer metastases revealed the presence of significantly more newly formed bone tissue with the administration of CF-CDDP. Local administration of CF-CDDP is expected to become the first therapy to suppress cancer growth with low prevalence of adverse reactions, and to repair bone damaged by metastasis.

Purpose Multiwalled carbon nanotubes (MWCNTs) have been known to enter the circulatory system via the lungs from inhalation exposure; however, its carcinogenicity and subsequent accumulation in other organs have not been adequately reported in the literature. Moreover, the safety of MWCNTs as a biomaterial has remained a matter of debate, particularly when the material enters the circulatory system. To address these problems, we used carcinogenic rasH2 transgenic mice to intravenously administer highly dispersed MWCNTs and to evaluate their carcinogenicity and accumulation in the organs. Methods Two types of MWCNTs (thin- and thick-MWCNTs) were intravenously administered at a high dose (approximately 0.7 mg per kg body weight) and low dose (approximately 0.07 mg per kg body weight). Results MWCNTs showed pancreatic accumulation in 3.2% of mice administered with MWCNTs, but there was no accumulation in other organs. In addition, there was no significant difference in the incidence of tumor among the four MWCNTs-administered groups compared to the vehicle group without MWCNTs administration. Blood tests revealed elevated levels in mean red blood cell volume and mean red blood cell hemoglobin level for the MWCNTs-administered group, in addition to an increase in eotaxin. Conclusion The present study demonstrated that the use of current technology to sufficiently disperse MWCNTs resulted in minimal organ accumulation with no evidence of carcinogenicity.

Purpose Although both anti-PD-1 antibody and treatments using anti-PD-L1 antibody are currently in clinical use, their therapeutic effects vary according to cancer type. One of the factors accounting for this variability is the expression level of the immune checkpoint molecule that differs between cancer types; thus, it is important to clarify the relationship between clinical outcomes and immune checkpoint molecules for all types of human cancer. The purpose of this study is to evaluate the clinical outcome of osteosarcoma in relation to PD-L1, PRF, GZMB, and IFNγ expression. Methods Using 19 clinical specimens of osteosarcoma, we examined the expression of PD-L1, PRF, GZMB, and IFNγ in relation to their clinical outcomes. Results PD-L1 expression correlated with early metastatic formation in clinical specimens of osteosarcoma, and the group with highly expressed functional markers for T cells such as PRF and GZMB resulted in a long overall survival time. Conclusion This is the first study to elucidate the clinical outcomes of osteosarcoma in relation to PD-L1, PRF, GZMB, and IFNγ expression. This study provides valuable information regarding the clinical indication and prediction of effect for anti-PD-1 antibody in osteosarcoma.

One of the greatest challenges to overcome in the pursuit of the medical application of carbon nanomaterials (CNMs) is safety. Particularly, when considering the use of CNMs in drug delivery systems (DDSs), evaluation of safety at the accumulation site is an essential step. In this study, we evaluated the toxicity of carbon nanohorns (CNHs), which are potential DDSs, using human lymph node endothelial cells that have been reported to accumulate CNMs, as a comparison to fibrous, multi-walled carbon nanotubes (MWCNTs) and particulate carbon black (CB). The effect of different surface characteristics was also evaluated using two types of CNHs (untreated and oxidized). In the fibrous MWCNT, cell growth suppression, as well as expression of inflammatory cytokine genes was observed, as in previous reports. In contrast, no significant toxicity was observed for particulate CB and CNHs, which was different from the report of CB cytotoxicity in vascular endothelial cells. These results show that (1) lymph endothelial cells need to be tested separately from other endothelial cells for safety evaluation of nanomaterials, and (2) the potential of CNHs as DDSs., Article, NANOMATERIALS. 10(7):1374 (2020)

Introduction: Carbon nanotubes (CNTs) have various shapes, including needle-like shapes and curled shapes, and the cytotoxicity and carcinogenicity of CNTs differ depending on their shapes and surface modifications. However, the biological responses induced by CNTs and related mechanisms according to the dispersion state of CNTs have not been extensively studied.Materials and methods: We prepared multiwalled CNTs (MWCNTs) showing different dispersions and evaluated these MWCNTs in RAW264 cells to determine cytotoxicity, cellular uptake, and immune responses. Furthermore, RAW264 cells were also used to compare the cellular uptake and cytotoxicity of fibrous MWCNTs and spherical carbon nanohorns (CNHs) exhibiting the same degree of dispersion.Results: Our analysis showed that the cellular uptake, localization, and inflammatory responses of MWCNTs differed depending on the dispersion state. Moreover, there were differences in uptake between MWCNTs and CNHs, even showing the same degree of dispersion. These findings suggested that receptors related to cytotoxicity and immune responses differed depending on the aggregated state of MWCNTs and surface modification with a dispersant. Furthermore, our results suggested that the receptors recognized by the cells differed depending on the particle shape.Conclusion: Therefore, to apply MWCNTs as a biomaterial, it is important to determine the carcinogenicity and toxicity of the CNTs and to examine different biological responses induced by varying shapes, dispersion states, and surface modifications of particles., Article, INTERNATIONAL JOURNAL OF NANOMEDICINE. 13:6079-6088(2018)

Background Maternal smoking during pregnancy is a major risk for adverse perinatal outcomes, as well as children's health status. Thus, it is important to describe maternal smoking status during pregnancy and child-rearing to devise better intervention strategies. However, there have been no longitudinal studies to describe the status. Thus, in this study, we aimed to describe maternal smoking status during pregnancy and child-rearing based on population-based maternal and child health information. Moreover, we explored the factors associated with maternal smoking relapse after delivery. Methods We performed a survey of 1,220 mothers in a Japanese rural area who responded to a questionnaire upon registration of their pregnancies. When their children received health checkups at 4, 18, and 36 months of age, maternal smoking status was also surveyed. We then performed multiple logistic regression analysis to explore factors associated with maternal smoking relapse after delivery. Results Ultimately, the total number of mothers with data available for longitudinal analysis was 727 (59.6%). At the time of pregnancy registration, there were 74 current smokers (10.2%) and 176 former smokers (24.2%). Among them, 59 (33.5%) relapsed after delivery. Under 28 years of maternal age at pregnancy registration (OR 2.6; 95% CI, 1.2-5.4) was associated with maternal smoking relapse after delivery. Conclusions Longitudinal analyses showed that about 60% of mothers who smoked before and after delivery failed smoking cessation. In addition, younger mothers were significantly likely to relapse smoking after delivery.

Background There are many types of therapies for cancer. In these days, immunotherapies, especially immune checkpoint inhibitors, are focused on. Though many types of immune checkpoint inhibitors are there, the difference of effect and its mechanism are unclear. Some reports suggest the response rate of anti-PD-1 antibody is superior to that of anti-PD-L1 antibody and could potentially produce different mechanisms of action. On the other hand, Treg also express PD-1; however, their relationship remains unclear. Methods In this study, we used osteosarcoma cell lines in vitro and osteosarcoma mouse model in vivo. In vitro, we analyzed the effect of IFN gamma for expression of PD-L1 on the surface of cell lines by flowcytometry. In vivo, murine osteosarcoma cell line LM8 was subcutaneously transplanted into the dorsum of mice. Mouse anti-PD-1 antibody was intraperitoneally administered. we analysed the effect for survival of anti-PD-1 antibody and proportion of T cells in the tumour by flowcytometry. Results We discovered that IFN gamma increased PD-L1 expression on the surface of osteosarcoma cell lines. In assessing the relationship between anti-PD-1 antibody and Treg, we discovered the administration of anti-PD-1 antibody suppresses increases in tumour volume and prolongs overall survival time. In the tumour microenvironment, we found that the administration of anti-PD-1 antibody decreased Treg within the tumour and increased tumour-infiltrating lymphocytes. Conclusions Here we clarify for the first time an additional mechanism of anti-tumour effect-as exerted by anti-PD-1 antibody decreasing Treg- we anticipate that our findings will lead to the development of new methods for cancer treatment., Article, BMC CANCER. 20(1):25 (2020)

We evaluated starfish-derived &beta, tricalcium phosphate (Sf-TCP) obtained by phosphatization of starfish-bone-derived porous calcium carbonate as a potential bone substitute material. The Sf-TCP had a communicating pore structure with a pore size of approximately 10 &mu, m. Although the porosity of Sf-TCP was similar to that of Cerasorb M (CM)&mdash, a commercially available &beta, TCP bone filler&mdash, the specific surface area was roughly three times larger than that of CM. Observation by scanning electron microscopy showed that pores communicated to the inside of the Sf-TCP. Cell growth tests showed that Sf-TCP improved cell proliferation compared with CM. Cells grown on Sf-TCP showed stretched filopodia and adhered, cells migrated both to the surface and into pores. In vivo, vigorous tissue invasion into pores was observed in Sf-TCP, and more fibrous tissue was observed for Sf-TCP than CM. Moreover, capillary formation into pores was observed for Sf-TCP. Thus, Sf-TCP showed excellent biocompatibility in vitro and more vigorous bone formation in vivo, indicating the possible applications of this material as a bone substitute. In addition, our findings suggested that mimicking the microstructure derived from whole organisms may facilitate the development of superior artificial bone.

Purpose Although both anti-PD-1 antibody and treatments using anti-PD-L1 antibody are currently in clinical use, their therapeutic effects vary according to cancer type. One of the factors accounting for this variability is the expression level of the immune checkpoint molecule that differs between cancer types; thus, it is important to clarify the relationship between clinical outcomes and immune checkpoint molecules for all types of human cancer. The purpose of this study is to evaluate the clinical outcome of osteosarcoma in relation to PD-L1, PRF, GZMB, and IFNγ expression. Methods Using 19 clinical specimens of osteosarcoma, we examined the expression of PD-L1, PRF, GZMB, and IFNγ in relation to their clinical outcomes. Results PD-L1 expression correlated with early metastatic formation in clinical specimens of osteosarcoma, and the group with highly expressed functional markers for T cells such as PRF and GZMB resulted in a long overall survival time. Conclusion This is the first study to elucidate the clinical outcomes of osteosarcoma in relation to PD-L1, PRF, GZMB, and IFNγ expression. This study provides valuable information regarding the clinical indication and prediction of effect for anti-PD-1 antibody in osteosarcoma.

Purpose Multiwalled carbon nanotubes (MWCNTs) have been known to enter the circulatory system via the lungs from inhalation exposure; however, its carcinogenicity and subsequent accumulation in other organs have not been adequately reported in the literature. Moreover, the safety of MWCNTs as a biomaterial has remained a matter of debate, particularly when the material enters the circulatory system. To address these problems, we used carcinogenic rasH2 transgenic mice to intravenously administer highly dispersed MWCNTs and to evaluate their carcinogenicity and accumulation in the organs. Methods Two types of MWCNTs (thin- and thick-MWCNTs) were intravenously administered at a high dose (approximately 0.7 mg per kg body weight) and low dose (approximately 0.07 mg per kg body weight). Results MWCNTs showed pancreatic accumulation in 3.2% of mice administered with MWCNTs, but there was no accumulation in other organs. In addition, there was no significant difference in the incidence of tumor among the four MWCNTs-administered groups compared to the vehicle group without MWCNTs administration. Blood tests revealed elevated levels in mean red blood cell volume and mean red blood cell hemoglobin level for the MWCNTs-administered group, in addition to an increase in eotaxin. Conclusion The present study demonstrated that the use of current technology to sufficiently disperse MWCNTs resulted in minimal organ accumulation with no evidence of carcinogenicity.

Many biomaterials have been evaluated using cultured cells. In particular, osteoblast-like cells are often used to evaluate the osteocompatibility, hard-tissue-regeneration, osteoconductive, and osteoinductive characteristics of biomaterials. However, the evaluation of biomaterial osteogenesis-inducing capacity using osteoblast-like cells is not standardized; instead, it is performed under laboratory-specific culture conditions with different culture media. However, the effect of different media conditions on bone formation has not been investigated. Here, we aimed to evaluate the osteogenesis of MC3T3-E1 cells, one of the most commonly used osteoblast-like cell lines for osteogenesis evaluation, and assayed cell proliferation, alkaline phosphatase activity, expression of osteoblast markers, and calcification under varying culture media conditions. Furthermore, the various media conditions were tested in uncoated plates and plates coated with collagen type I and poly-L-lysine, highly biocompatible molecules commonly used as pseudobiomaterials. We found that the type of base medium, the presence or absence of vitamin C, and the freshness of the medium may affect biomaterial regeneration. We posit that an in vitro model that recapitulates in vivo bone formation should be established before evaluating biomaterials., Article, International Journal of Molecular Sciences. 22(14):7752 (2021)

A design of novel synthetic polymers possessing metallic properties is studied on the basis of the one-dimensional tight-binding self consistent field-crystal orbital (SCF-CO) method. The idea presented here is to utilize crossing π bands of polyperylene (PP) and poly(p-phenylene) (PPP) by controlling the number of π electrons in the polymer skeletons. It is suggested that nitrogen-substituted PP, nitrogen-substituted PPP and boron-substituted PPP can be candidates for showing intrinsic metallic properties.

The electronic structures of polyacenacene (PAA) and its geometrical isomer, polyphenanthrophenanthrene (PPhP) have been studied using the tight-binding SCF-CO (self consistent field-crystal orbital) method with respect to a design of one-dimensional (1D) graphite. The geometry of each polymer is optimized from the energetic point of view. It has been found that from the analysis of the electronic structure of its optimized geometry, PAA favours the structure without the carbon-carbon bond alternations, yielding no band gap. In this sense, PAA is a typical 1D-graphite. On the other hand, it is predicted that the magnitude of the band gap of PPhP in its optimized geometry is almost equal to that of trans -polyacetylene.