Histological and Immunohistochemical Features of Normal Histiocytes and Langerhans Cells, and Histiocytic Sarcomas in Four-Toed Hedgehogs (Atelerix albiventris).

Histiocytic sarcoma (HS) is a haematopoietic tumour of histiocyte origin that has been sporadically reported in four-toed hedgehogs (Atelerix albiventris). The present study aimed to investigate clinical, gross, histopathological and immunohistochemical features of HS in eight hedgehogs. Histological and immunohistochemical features of normal histiocytes and Langerhans cells (LCs) of hedgehogs were also investigated. HLA-DR-, Iba-1- and E-cadherin-positive LCs were observed in the epidermis, while Iba-1- and CD204-positive histiocytes were detected in the lymph nodes and spleen of normal hedgehogs. Localized HS (six cases) developed in the skin and spleen, while disseminated HS (two cases) occurred in the intestine. Tumour cells of disseminated HS were also distributed within the mesenteric lymph nodes, liver, kidney, spleen, lung and adrenal glands. Tumour cells of both localized and disseminated HS were composed of histiocytic cells, spindle to pleomorphic cells, multinucleated giant cells and erythrophagocytic cells. Most tumour cells were immunopositive for Iba-1, CD204 and lysozyme. A small number of tumour cells were positive for E-cadherin and CD208, and the tumour cells in one case were positive for HLA-DR. These results suggest that the tumour cells have variable features of histiocyte origin, including dendritic cells, LCs and macrophages. The behaviour of HS in the hedgehog was very aggressive, and 50% of cases died within 90 days of resection. The present study also highlighted the tendency for local tumour recurrence in localized cutaneous HS cases, suggesting a requirement for a long-term follow-up after excision.

Lachrymal Gland Basal Cell Adenocarcinoma in a Ferret (Mustela putorius furo).

A 1 cm diameter mass was detected in the caudal superotemporal area of the left eye of a 6-year-old neutered male ferret (Mustela putorius furo). The mass and the left eye were removed surgically. Microscopical examination revealed a tumour of the adnexal gland of the eye that had invaded the surrounding ocular muscle. The tumour was composed of basal-type epithelial cells arranged in a solid, or occasionally tubular, pattern. Immunohistochemically, the tumour cells expressed cytokeratin and p63, but not smooth muscle actin. Based on these findings, the tumour was diagnosed as a basal cell adenocarcinoma of the lachrymal gland. In addition to the tumour, the retina of the left eye was detached and folded at the centre of the globe. This is the first report of a non-human case of basal cell adenocarcinoma of the lachrymal gland.

Salivary Gland Epithelial-Myoepithelial Carcinoma with High-Grade Transformation in a Dog.

An 8-year-old male neutered standard dachshund was presented with a slowly growing mass in the left submandibular salivary gland. Histopathological examination revealed a tumour that was composed of bilayered duct-like structures with an inner layer of ductal cells and an outer layer of clear cells. Both inner and outer cells in the greater part of the tumour exhibited low to moderate atypia and low mitotic activity. However, a focal area towards the periphery showed enhanced cellular atypia and mitotic activity in tumour cells. Immunohistochemically, the outer layer of clear cells expressed myoepithelial markers, while the inner layer cells were positive for a luminal epithelial marker. No local recurrence or lymph node or distant metastasis was observed 18 months following surgery. Based on the morphology and immunohistochemical findings, a final diagnosis of epithelial-myoepithelial carcinoma with high-grade transformation was made.

Regulation of somatostatin receptor 4-mediated cytostatic effects by CD26 in malignant pleural mesothelioma.

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive neoplasm arising from mesothelial lining of pleura. CD26 molecules preferentially expressed on epithelioid type of MPM. This study investigates the molecular mechanisms of CD26 regulating MPM cells in vitro and in vivo. METHODS: Biochemical and cell biological approaches were used for identifying a novel molecular target of MPM. Its contribution to tumour expansion has been also assessed using animal models. The clinical samples of MPM were also assessed for its expression. RESULTS: We identify that cytostatic effects in MPM are mediated by somatostatin (SST) receptor 4 (SSTR4), being inhibited by the interaction of CD26 molecules. We also indicates that SSTR4-mediated cytostatic effects are regulated by SHP-2 PTP, and that this inhibitory effect by SST agonist is enhanced via lipid raft clustering of associated molecules following crosslinking of anti-CD26 antibody. Finally, using an in vivo xenograft model, we demonstrate that the anti-tumour effect of anti-CD26 mAb is enhanced when combined with SSTR4 agonist treatment, and that SSTR4 is highly coexpressed with CD26 on epithelioid or biphasic types of MPM tissues obtained from patients' surgical specimens. CONCLUSIONS: Combination therapy with humanised anti-CD26 mAb and SSTR4 agonist may therefore potentiate anti-tumour effect on MPM.

Increased ratio of FoxP3+ regulatory T cells/CD3+ T cells in skin lesions in drug-induced hypersensitivity syndrome/drug rash with eosinophilia and systemic symptoms.

BACKGROUND: Drug-induced hypersensitivity syndrome/drug rash with eosinophilia with systemic symptoms (DIHS/DRESS) is a severe drug eruption accompanied by multiorgan disorders. Several unique aspects of DIHS/DRESS, including herpesvirus reactivation, liver dysfunction and hypogammaglobulinaemia, have similarities to graft-versus-host disease (GVHD). AIM: In this study, we focused on the dynamics of regulatory T cells (Tregs) infiltrating into the skin lesions of DIHS/DRESS and GVHD. METHODS: Skin biopsies were taken from patients with DIHS/DRESS, GVHD, or maculopapular drug eruption. Tregs were detected using immunostaining with anti-FoxP3. RESULTS: The ratio of FoxP3+ T cells to CD3+ T cells was significantly higher in the skin lesions of patients with DIHS/DRESS than in those of patients with GVHD, and was positively correlated with the number of days from disease onset in the acute phase. CONCLUSIONS: The dynamics of Tregs in skin lesions are different between DIHS/DRESS and GVHD, despite there being many similarities between these conditions.

Differences in indicators of malignancy between luminal epithelial cell type and myoepithelial cell type of simple solid carcinoma in the canine mammary gland.

Routinely diagnosed simple solid carcinoma (SSC) of the canine mammary gland comprises a heterogeneous group of tumors. Seventy-two cases that had been diagnosed as SSC based on hematoxylin and eosin-stained tissue sections were reclassified immunohistochemically on the basis of myoepithelial markers p63 and α-smooth muscle actin, as well as a luminal epithelial marker cytokeratin 8. Only 23 cases (32%) were true SSC, composed only of luminal epithelial cells, whereas 11 cases (15%) were malignant myoepithelioma (MM), composed predominantly of myoepithelial cells, and 38 cases (53%) were biphasic carcinoma (BC), characterized by biphasic proliferation of luminal epithelial and basal/myoepithelial components. As the pathological parameters were compared between the reclassified tumor types, infiltrative potential, vascular/lymphatic invasion, lymph node metastasis, and Ki-67 labeling index were higher in true SSC compared with MM and BC, suggesting that the former may exhibit a poorer prognosis compared with the latter two.

Condyloma acuminata induces focal intense FDG uptake mimicking vaginal stump recurrence from uterine cervical cancer: a case report.

The 2-deoxy-2-[18F] fluoro-D-glucose position emission tomography/computed tomography (FDG PET/CT) findings of condyloma acuminata in a patient with FIGO Stage IB1 cervical cancer who had previously been treated with radical hysterectomy, pelvic chemoradiotherapy, and consolidation chemotherapy is described in this article. This case highlights the importance of considering condyloma acuminata during the differential diagnosis of abnormal vaginal FDG uptake in patients who have been treated for gynecological cancer.

Clinical outcomes of endoscopic resection for nonampullary duodenal high-grade dysplasia and intramucosal carcinoma.

This study retrospectively analyzed the clinical outcomes of endoscopic resection of 26 sporadic (i. e., not associated with polyposis syndrome) nonampullary duodenal lesions representing high-grade dysplasia or intramucosal carcinoma (duodenal HGD/IMC) in 23 patients. No severe complications such as perforation were observed, but three cases of delayed bleeding were seen. The use of endoscopic clips significantly decreased the delayed bleeding rate (0/19, 0%) compared with cases in which clips were not used (3/7, 42.9%; P = 0.013, χ2 test). Eighteen lesions (69.2%) were removed by en bloc resection. The follow-up period after resection was 25.5 ± 23.3 months. Two lesions (7.7%) that recurred locally were detected at the first surveillance endoscopy 3 months after resection. These lesions were 22 and 15 mm in size respectively and were resected piecemeal. Endoscopic resection is an effective and safe procedure for treating duodenal HGD/IMC. En bloc resection and prophylactic clip usage are encouraged.

Turn motif phosphorylation negatively regulates activation loop phosphorylation in Akt.

Akt, also known as protein kinase B, has a central role in various signaling pathways that regulate cellular processes such as metabolism, proliferation and survival. On stimulation, phosphorylation of the activation loop (A-loop) and hydrophobic motif (HM) of Akt by the kinase phosphoinositide-dependent kinase 1 (PDK1) and the mammalian target of rapamycin complex 2 (mTORC2), respectively, results in Akt activation. A well-conserved threonine in the turn motif (TM) is also constitutively phosphorylated by mTORC2 and contributes to the stability of Akt. The role of TM phosphorylation in HM and A-loop phosphorylation has not been sufficiently evaluated. Using starfish oocytes as a model system, this study provides the first evidence that TM phosphorylation has a negative role in A-loop phosphorylation. In this system, the maturation-inducing hormone, 1-methyladenine, stimulates Akt to reinitiate meiosis through activation of cyclin B-Cdc2. The phosphorylation status of Akt was monitored via introduction of exogenous human Akt (hAkt) in starfish oocytes. TM and HM phosphorylation was inhibited by microinjection of an anti-starfish TOR antibody, but not by rapamycin treatment, suggesting that both phosphorylation events depend on TORC2, as reported in mammalian cells. A single or double alanine substitution at each of three phosphorylation residues revealed that TM phosphorylation renders Akt susceptible to dephosphorylation on the A-loop. When A-loop phosphatase was inhibited by okadaic acid (OA), TM phosphorylation still reduced A-loop phosphorylation, suggesting that the effect is caused at least partially through reduction of sensitivity to PDK1. Negative regulation by TM phosphorylation was also observed in constitutively active Akt and was functionally reflected in meiosis resumption. By contrast, HM phosphorylation enhanced A-loop phosphorylation and achieved full activation of Akt via a mechanism at least partially independent of TM phosphorylation. These observations provide new insight into the mechanism controlling Akt phosphorylation in the cell.

Membrane-bound CD40 ligand on T cells from mice injected with lipopolysaccharide accelerates lipopolysaccharide-induced osteoclastogenesis.

BACKGROUND AND OBJECTIVE: T cells infiltrate the inflammatory site of periodontitis and consequently stimulate the loss of periodontal bone. We previously reported that T cells from lipopolysaccharide (LPS)-injected mice (LPS-T cells) accelerated osteoclastogenesis in the presence of LPS. Ηowever, the detailed mechanism of this acceleration is still unclear. In this study, we analyzed the mechanism of osteoclastogenesis accelerated by LPS-T cells. MATERIAL AND METHODS: We examined the mechanism of osteoclastogenesis acceleration. First, to determine the effect of cell-to-cell contact, we co-cultured T cells and bone marrow macrophages, prestimulated with RANKL for 48 h (R-BMMs), in the presence of LPS for 24 h, in a Transwell. Second, to determine the effect of CD40 ligand (CD40L), we co-cultured T cells and R-BMMs in the presence of LPS and anti-CD40L immunoglobulin. Third, we examined the effect of recombinant mouse CD40L (rCD40L) in the presence of LPS in vitro and in vivo. Lastly, we examined the expression of membrane-bound CD40L (mCD40L) by fluorescence-activated cell sorting (FACS). RESULTS: Blocking cell-to-cell contact between LPS-T cells and R-BMMs completely inhibited the acceleration of osteoclastogenesis. Anti-CD40L immunoglobulin also completely inhibited the acceleration of osteoclastogenesis. Moreover, rCD40L accelerated osteoclastogenesis in the presence of LPS in vitro and in vivo. Finally, the expression of mCD40L on LPS-T cells was higher than that on T cells isolated from mice not injected with LPS. CONCLUSION: The results demonstrate that CD40L accelerates osteoclastogenesis in the presence of RANKL and LPS. The results also suggest that mCD40L on LPS-T cells accelerates osteoclastogenesis.

Locally administered interferon-γ accelerates lipopolysaccharide-induced osteoclastogenesis independent of immunohistological RANKL upregulation.

BACKGROUND AND OBJECTIVE: Interferon-γ (IFN-γ) potently inhibits RANKL-induced osteoclastogenesis in vitro. In contrast, previous studies have shown that an increase in IFN-γ expression is correlated with an increase in lipopolysaccharide (LPS)-induced bone loss in vivo. However, it is not clear whether local IFN-γ accelerates osteoclastogenesis or not in vivo. Therefore, the aim of this study was to clarify the role of local IFN-γ in LPS-induced osteoclastogenesis. MATERIALS AND METHODS: We induced bone loss in calvaria by injecting LPS. One group of mice received an IFN-γ injection together with LPS injection, while another group received IFN-γ 2 d after LPS injection. Bone resorption was observed histologically. Next, we stimulated murine bone marrow macrophages with macrophage-colony stimulating factor and RANKL in vitro. We added different doses of IFN-γ and/or LPS at 0 or 48 h time points. Cells were stained with tartrate-resistant acid phosphatase at 72 h. RESULTS: Local administration of IFN-γ together with LPS injection did not affect osteoclast formation. However, IFN-γ injected after LPS injection accelerated osteoclast formation. Also, we confirmed that IFN-γ added at 0 h inhibited RANKL-induced osteoclastogenesis in vitro. However, inhibition by IFN-γ added at 48 h was reduced compared with that by IFN-γ added at 0 h. Interestingly, IFN-γ together with a low concentration of LPS accelerated osteoclast formation when both were added at 48 h compared with no addition of IFN-γ. CONCLUSION: The results suggest that local IFN-γ accelerates osteoclastogenesis in certain conditions of LPS-induced inflammatory bone loss.

The intracellular accumulation of phagocytic and epithelial cells and the inhibitory effect on Chlamydophila (Chlamydia) pneumoniae of telithromycin and comparator antimicrobials.

The intracellular accumulation of telithromycin was measured and compared with ciprofloxacin, clarithromycin, minocycline and erythromycin. The activities of telithromycin, clarithromycin and minocycline against Chlamydophila (Chlamydia) pneumoniae were compared in an intracellular killing assay. Maximal telithromycin accumulation (mean intracellular/extracellular concentration ratio) ranged from 6.7 (A549 lung epithelial cells) to 11.8 (THP-1 monocytic cells). This ratio was similar to that of clarithromycin, but less than for minocycline. Minimum inhibitory and minimum lethal telithromycin concentrations against six clinical strains of C. pneumoniae were <0.015-0.03 mg/L and 0.03-0.06 mg/L, respectively, which were lower than those found for minocycline. These results show that telithromycin accumulates rapidly into epithelial cells, similar to previously reported results for phagocytic cells. Intracellular accumulation of telithromycin was lower than that observed for minocycline, but telithromycin demonstrated substantially more potent antichlamydial activity.

Expression and localization of ATP binding cassette (ABC) family of drug transporters in gastric hepatoid adenocarcinomas.

AIMS: Hepatoid adenocarcinomas are clinically chemoresistant; however, data concerning the mechanisms of chemoresistance are lacking. ATP-binding cassette (ABC) transporters play a role in the ATP-dependent outward efflux of drugs, and their function renders tumour cells multidrug resistant. We assumed that the expression of ABC transporters may be accompanied by hepatic differentiation because most ABC transporters are dominantly expressed in hepatocytes. The aim of this study was to investigate the expression of ABC transporters in hepatoid adenocarcinomas. METHODS AND RESULTS: The expression of P-glycoprotein, multidrug resistant-associated protein (MRP) 1, MRP2, MRP3 and MRP6 was investigated using immunohistochemistry in 13 cases of gastric hepatoid adenocarcinoma and 32 cases of control adenocarcinoma. P-glycoprotein was expressed in all cases examined. The positive rates of MRP1 (84.6% versus 21.9%), MRP2 (100% versus 43.8%) and MRP6 (61.5% versus 15.6%) were significantly higher in hepatoid than in control adenocarcinoma. MRP3 was negative in all hepatoid adenocarcinomas. Immunohistochemistry by polyclonal anti-carcinoembryonic antigen antibody, which detects bile canaliculi, suggested that MRP2 and MRP6 are located on bile canalicular-like structures in sheet or trabecular nests. CONCLUSIONS: These results support the hypothesis that ABC transporters participate in the mechanisms of multidrug resistance in hepatoid adenocarcinomas.

Humanized antihuman IL-6 receptor antibody, tocilizumab.

Interleukin-6 (IL-6) is a pleiotropic cytokine that regulates immune responses and inflammatory reactions. Overproduction of IL-6 has been shown to play a role in inflammatory autoimmune diseases such as rheumatoid arthritis (RA), and juvenile idiopathic arthritis (JIA) and, therefore, an agent blocking IL-6 actions can be a therapy of these diseases. IL-6 belongs to a cytokine family, which shares the cytokine receptor subunit glycoprotein (gp) 130. This family also includes IL-11, oncostatin-M, and leukemia inhibitory factor (LIF). In the IL-6 receptor (IL-6R) system, both a membrane-bound IL-6R and a soluble form of IL-6R are able to mediate IL-6 signals into the cells through the interaction of gp130. Tocilizumab is a humanized antihuman IL-6 receptor antibody designed using genetic engineering technology. Tocilizumab recognizes both the membrane-bound and the soluble form IL-6R and specifically blocks IL-6 actions. Tocilizumab is expected to ameliorate the autoimmune inflammatory diseases with IL-6 overproduction and has been clinically developed as a therapeutic agent for RA, systemic-onset and articular types of JIA, Crohn's disease, etc. Tocilizumab has been shown to be effective not only for improving signs and symptoms but also for preventing joint destruction of RA. Immunopharmacology and clinical benefit of tocilizumab in RA is addressed.

Adolescent smoking behaviour and cigarette brand preference in Japan.

OBJECTIVES: As part of efforts to develop a smoking control strategy for Japanese adolescents, the results of two nationwide surveys on adolescent smoking behaviour were compared. DESIGN: Descriptive study on smoking behaviour among high school students was conducted. Self-reporting anonymous questionnaires were administered to 115,814 students in 1996 and 106,297 in 2000 through randomly sampled junior and senior high schools throughout Japan. MAIN OUTCOME MEASURES: Smoking prevalence, proportion of smokers by usual sources of cigarettes, national estimated cigarettes consumed by minors, share of cigarette brands smoked by high school students. RESULTS: The experiment rate among junior high school boys decreased in 2000 compared with that in 1996, whereas current and daily smoking rates did not. Although prevalence among Japanese girls was much lower than that among boys, prevalence among girls increased in 2000. The main source of cigarettes among high school smokers was vending machines. The proportion of smokers who usually purchased cigarettes from vending machines increased in 2000, in spite of the 1998 introduction of restrictions on night-time operations. Japanese adolescents were more likely than adults to smoke American cigarette brands, and the adolescent market share of American brands has increased rapidly, especially for menthol brands. CONCLUSIONS: This survey revealed the seriousness of the problem of smoking behaviour among Japanese high school students, and suggested that this behaviour may be influenced by social environmental factors, including the marketing strategies of the tobacco industry. Action should be taken to reduce the prevalence and impact of pro-tobacco marketing messages and to abolish cigarette vending machines.

Suppressor of cytokine signaling-1 expression by infectivity-enhanced adenoviral vector inhibits IL-6-dependent proliferation of multiple myeloma cells.

Multiple myeloma (MM) accounts for 10% of hematological malignant disorders. Its refractory nature indicates the necessity of developing novel therapeutic modalities. Since interleukin 6 (IL-6) is one of the major growth factors for MM cells, we expressed suppressor of cytokine signaling-1 (SOCS-1), one of the blockades of IL-6 receptor downstream signaling, to suppress the proliferation of MM cells. Because MM cells are resistant to conventional adenoviral vector infection, we utilized infectivity-enhanced adenoviral vectors with an RGD4C motif in the adenoviral fiber-knob region (RGD-modified vector). In infectivity analysis, RGD-modified vectors were superior to unmodified controls in the majority of the MM cell lines tested. The overexpression of SOCS-1 using infectivity-enhanced adenoviral vectors achieved growth suppression in IL-6-dependent MM cells, but not in the IL-6-independent cells. IL-6-induced STAT3 phosphorylation was suppressed in IL-6-dependent cells, indicating that the signal transduction cascade of the IL-6 receptor signaling was blocked. In aggregate, SOCS-1 overexpression with RGD-modified adenoviral vectors achieved the antiproliferative effect in IL-6-dependent MM cells. These results provide an initial proof-of-principle of the anticancer effect of SOCS-1 expression vector as well as a promise for the future development of therapeutic modality for MM based on this vector.