A comparison of thyroidal protection by iodine and perchlorate against radioiodine exposure in Caucasians and Japanese.

Radioactive iodine released in nuclear accidents may accumulate in the thyroid and by irradiation enhances the risk of cancer. Radioiodine uptake into the gland can be inhibited by large doses of stable iodine or perchlorate. Nutritional iodine daily intake may impact thyroid physiology, so that radiological doses absorbed by the thyroid as well as thyroid blocking efficacy may differ in Japanese with a very rich iodine diet compared to Caucasians. Based on established biokinetic-dosimetric models for the thyroid, we derived the parameters for Caucasians and Japanese to quantitatively compare the effects of radioiodine exposure and the protective efficacy of thyroid blocking by stable iodine at the officially recommended dosages (100 mg in Germany, 76 mg in Japan) or perchlorate. The maximum transport capacity for iodine uptake into the thyroid is lower in Japanese compared to Caucasians. For the same radioiodine exposure pattern, the radiological equivalent thyroid dose is substantially lower in Japanese in the absence of thyroid blocking treatments. In the case of acute radioiodine exposure, stable iodine is less potent in Japanese (ED50 = 41.6 mg) than in Caucasians (ED50 = 2.7 mg) and confers less thyroid protection at the recommended dosages because of a delayed responsiveness to iodine saturation of the gland (Wolff-Chaikoff effect). Perchlorate (ED50 = 10 mg in Caucasians) at a dose of 1000 mg has roughly the same thyroid blocking effect as 100 mg iodine in Caucasians, whereas it confers a much better protection than 76 mg iodine in Japanese. For prolonged exposures, a single dose of iodine offer substantially lower protection than after acute radioiodine exposure in both groups. Repetitive daily iodine administrations improve efficacy without reaching levels after acute radioiodine exposure and achieve only slightly better protection in Japanese than in Caucasians. However, in the case of continuous radioiodine exposure, daily doses of 1000 mg perchlorate achieve a high protective efficacy in Caucasians as well as Japanese (> 0.98). In Caucasians, iodine (100 mg) and perchlorate (1000 mg) at the recommended dosages seem alternatives in case of acute radioiodine exposure, whereas perchlorate has a higher protective efficacy in the case of longer lasting radioiodine exposures. In Japanese, considering protective efficacy, preference should be given to perchlorate in acute as well as prolonged radioiodine exposure scenarios.

High-temperature-required protein A2 as a predictive marker for response to chemotherapy and prognosis in patients with high-grade serous ovarian cancers.

BACKGROUND: High-temperature-required protein A2 (HtrA2), a protein relating with apoptosis in a caspases-dependent and non-dependent manner, has been reported to be associated with chemosensitivity in several human cancers. METHODS: Tissue microarrays made from 142 patients with high-grade serous ovarian adenocarcinoma were evaluated to assess whether HtrA2 expression was related with several clinical parameters. RESULTS: Negative HtrA2 expression was observed in 36 cases (25%) of the patients, and related with significantly lower response rates of primary chemotherapy than those with positive HtrA2 expression (56% vs 83%, P<0.01). In addition, negative HtrA2 expression was identified as an independent worse prognostic factor for progression-free survival and overall survival by multivariate analyses. Furthermore, HtrA2 downregulation modulated sensitivity to platinum in serous ovarian cancer cells in vitro. CONCLUSIONS: HtrA2 expression was a predictor for sensitivity to chemotherapy, and could be a candidate of molecular target in the treatment of high-grade serous ovarian cancers.

X-chromosome-linked inhibitor of apoptosis as a key factor for chemoresistance in clear cell carcinoma of the ovary.

BACKGROUND: X-chromosome-linked inhibitor of apoptosis (XIAP) is one of the anti-apoptotic proteins leading to chemoresistance in several cancers. The aim of this study is to evaluate the impact of XIAP expression upon ovarian clear cell carcinoma (CCC) that has a platinum-resistant phenotype. METHODS: Tissue microarrays made from 90 CCC patients were analysed for immunohistochemical expression levels of XIAP, c-Met, p-Akt and Bcl-XL. In addition, CCC cell lines were evaluated whether XIAP silencing could modulate sensitivity to platinum agent in vitro. RESULTS: High XIAP expression was observed in 30 (33%) of 90 CCC cases, and was associated with c-Met (<0.01) and Bcl-XL (<0.01) expression. Cases with high XIAP expression had lower response rate to primary platinum-based chemotherapy (10% vs 65%, P=0.02). In stages II-IV tumours, high XIAP expression was related with worse progression-free survival (PFS, P=0.02). Furthermore, high XIAP expression was identified as an independent worse prognostic factor for PFS and overall survival. Finally, downregulation of XIAP using XIAP-specific small interfering RNA increased sensitivity to cisplatin in human cancer cells derived from CCC. CONCLUSIONS: X-chromosome-linked inhibitor of apoptosis expression was correlated with chemoresistance of primary chemotherapy, and identified as a prognostic marker for CCC. X-chromosome-linked inhibitor of apoptosis could be a candidate for new therapeutic target in CCC.

Looking at the formulation of national biosecurity education action plans.

In order for states to be assured of their compliance with the requirements of the Biological and Toxin Weapons Convention, it is necessary that all those science and policy stakeholders working within that state should be aware of their responsibilities under the Convention. This can only be achieved through a comprehensive national biosecurity education programme. We propose that each state should produce a national biosecurity action plan, with accompanying resources and materials to achieve this. A number of resources are already available online to support states in this challenge. We present a model for a national biosecurity action plan and propose a number of ways in which this may be achieved.

Identification of ABCG2 as an Exporter of Uremic Toxin Indoxyl Sulfate in Mice and as a Crucial Factor Influencing CKD Progression.

Chronic kidney disease (CKD) patients accumulate uremic toxins in the body, potentially require dialysis, and can eventually develop cardiovascular disease. CKD incidence has increased worldwide, and preventing CKD progression is one of the most important goals in clinical treatment. In this study, we conducted a series of in vitro and in vivo experiments and employed a metabolomics approach to investigate CKD. Our results demonstrated that ATP-binding cassette transporter subfamily G member 2 (ABCG2) is a major transporter of the uremic toxin indoxyl sulfate. ABCG2 regulates the pathophysiological excretion of indoxyl sulfate and strongly affects CKD survival rates. Our study is the first to report ABCG2 as a physiological exporter of indoxyl sulfate and identify ABCG2 as a crucial factor influencing CKD progression, consistent with the observed association between ABCG2 function and age of dialysis onset in humans. The above findings provided valuable knowledge on the complex regulatory mechanisms that regulate the transport of uremic toxins in our body and serve as a basis for preventive and individualized treatment of CKD.

Mice deficient in Vbeta8+NKT cells are resistant to experimental hepatitis but are partially susceptible to generalised Shwartzman reaction.

NKT cells are responsible for hepatitis induced either by concanavalin A (Con-A) or alpha-galactosylceramide (alpha-GalCer), and they are also profoundly involved in the generalised Shwartzman reaction (GSR) induced by consecutive injections of interleukin (IL)-12 and lipopolysaccharide (LPS). In the present study, using NC/Nga (NC) mice and SJL mice lacking the Vbeta(+)8 gene, we examined the role of Vbeta(+)8+NKT cells in hepatitis models and in the GSR. The absence of Vbeta(+)8+NKT cells in the liver mononuclear cells (MNC) was confirmed by the alpha-GalCer/CD1d/Ig dimer. Unexpectedly, other dimer+NKT cells including Vbeta7(+)NKT cells in these mice were found to decrease in comparison to that of C57BL/6 mice. No significant hepatocyte injury was observed after alpha-GalCer or Con-A administration in either mice. The serum interferon (IFN)-gamma, IL-4 and tumour necrosis factor (TNF) levels did not increase in these mice after alpha-GalCer injection, however these cytokines substantially increased after Con-A administration, thus suggesting that the roles of NKT cells differ between the two hepatitis models. However, in GSR, although neither mice showed lower IFN-gamma levels after a priming IL-12 injection, they showed TNF levels comparable to those in normal mice after LPS injection, and thus resulted in a decreased but substantial mortality. Although liver MNC from IL-12-injected SJL mice showed an impaired antitumour cytotoxicity, liver MNC of NC mice exhibited a greater antitumour cytotoxicity than that of C57BL/6 mice because liver NK cells proportionally increased in NC mice. These results confirm the critical role that Vbeta8(+)NKT cells play in both liver and multi-organ injury.

Photodynamic therapy mediates innate immune responses via fibroblast-macrophage interactions.

Antibacterial photodynamic therapy (PDT) has come to attract attention as an alternative therapy for drug-resistant bacteria. Recent reports revealed that antibacterial PDT induces innate immune response and stimulates abundant cytokine secretion as a part of inflammatory responses. However, the underlying mechanism how antibacterial PDT interacts with immune cells responsible for cytokine secretion has not been well outlined. In this study, we aimed to clarify the difference in gene expression and cytokine secretion between combined culture of fibroblasts and macrophages and their independent cultures. SCRC-1008, mouse fibroblast cell line and J774, mouse macrophage-like cell line were co-cultured and PDT treatments with different parameters were carried out. After various incubation periods (1-24 h), cells and culture medium were collected, and mRNA and protein levels for cytokines were measured using real-time PCR and ELISA, respectively. Our results showed that fibroblasts and macrophages interact with each other to mediate the immune response. We propose that fibroblasts initially respond to PDT by expressing Hspa1b, which regulates the NF-κB pathway via Tlr2 and Tlr4. Activation of the NF-κB pathway then results in an enhanced secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1ß) and neutrophil chemoattractant MIP-2 and KC from macrophages.

Different mechanisms between premitotic apoptosis and postmitotic apoptosis in X-irradiated U937 cells.

PURPOSE: Apoptosis is currently being evaluated for its importance as a pathway of radiation-induced cell death. However, the difference in the mechanisms between premitotic and postmitotic apoptosis following X-irradiation remains not well understood. We show here that the human monoblastoid cell line U937 can be induced to undergo these two different types of apoptosis. METHODS AND MATERIALS: U937 cells were irradiated at a dose of 5 or 20 Gy, and the DNA fragmentation rate was measured by both flow cytometric analysis and gel electrophoresis. Activation of caspase-3 was detected by Western blot analysis and fluorogenic assay using acetyl-Asp-Glu-Val-Asp-7-amino-4-methyl-coumarin (Ac-DEVD-AMC). Detection of mitochondrial transmembrane potential (DeltaPsi) was performed by using Rho123. Chasing of S-phase fraction following X-irradiation was performed after labeling with 5-bromo-2'-deoxyuridine (BrdU). Thymidine was used for synchronization of the cells. Inhibition of caspase-3 activity was achieved by Acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO). RESULTS: Time courses of the apoptotic rates, caspase activation, and DeltaPsi indicated that two different types of cell death were induced by the different X-ray doses. High-dose X-ray (20 Gy) induced a rapid and strong apoptosis, whereas low-dose X-ray (5 Gy) induced a slow and mild apoptosis. Cell-cycle analyses revealed that there was cell death before cell division in the former apoptosis but the cells must be dying after cell division in the latter apoptosis. By means of cell-cycle synchronization, the S-phase cells proved to be the most sensitive fraction to premitotic apoptosis, but an obvious difference in the susceptibility to cell death among the cell-cycle phases was not observed in postmitotic apoptosis. Ac-DEVD-CHO treatment effectively blocked caspase activity and premitotic apoptosis, but it failed to block postmitotic apoptosis. CONCLUSIONS: Irradiation of U937 cells at different X-ray doses induced two different types of apoptotic cell death, premitotic apoptosis and postmitotic apoptosis, which are characterized by the time course and cell-cycle specificity. Decision concerning these two types of apoptotic cell death may be made by the difference in the magnitude of cell damage following X-irradiation.

Simplified method for isolation of white cells from whole blood suitable for direct polymerase chain reaction.

A simple method for isolating mononuclear cells from whole blood is described. The procedure utilizes phytohemagglutinin to agglutinate the erythrocytes, separating white cells from whole blood in a very brief handling time. The isolated cells are readily subjected to DNA isolation simply by boiling, and the released DNA can be directly employed for the polymerase chain reaction analysis. The efficiency of this method is similar to other conventional methods, but less costly and less time-consuming. This method is particularly useful in analyzing DNA samples from the peripheral blood cells when the simplicity and low cost of the assay are preferable.

Maternal germinal mosaicism of X-linked agammaglobulinemia.

X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by abnormalities in tyrosine kinase (BTK), and is characterized by a deficiency of peripheral blood B cells. We studied cytoplasmic expression of BTK protein and analyzed the BTK gene (BTK) in peripheral blood mononuclear cells from two siblings with XLA and additional family members. Cytoplasmic expression of BTK protein in monocytes was not detected in either patient with XLA. A single base deletion (C563) in BTK-exon 6, which encodes the TH domain, was identified in both XLA patients. However, normal cytoplasmic expression of BTK protein in monocytes was detected in their mother without any BTK mutation. These results strongly suggest germinal mosaicism in the mother.

Urokinase type plasminogen activator and its receptor regulate the invasive potential of gastric cancer cell lines.

To assess the role of urokinase-type plasminogen activator (uPA) and uPA receptor (uPAR) on the invasive potential of cancer cells, in vitro experiments were performed using two human gastric cancer cell lines, NUGC-3 and MKN-28. NUGC-3 cells secreted a higher level of uPA than MKN-28 cells, while the uPAR expression of NUGC-3 cells was lower than that of MKN-28 cells. Both cancer cell lines expressed Met protein and did not express hepatocyte growth factor (HGF). In Matrigel invasion assay, MKN-28 cells demonstrated significantly lower invasion index than NUGC-3 cells. The addition of exogenous uPA significantly increased the invasive activity of MKN-28 cells. The uPA expression in NUGC-3 cells was enhanced by adding conditioned media of fibroblast cells or HGF. These results suggest that uPA promotes the invasive capacity of the uPAR-positive cancer cells, and that stromal cells may play an important role in cancer cell invasion by supplying uPA and/or promoting uPA production.

Telomerase activity and expression of human telomerase RNA component and human telomerase reverse transcriptase in lung carcinomas.

The aim of this study was to evaluate the usefulness of determination of telomerase activity and expression of human telomerase RNA component (hTERC) and human telomerase reverse transcriptase (hTERT) for the diagnosis of lung carcinomas. The tissues studied consisted of 115 carcinomas and adjacent nonneoplastic lung, which were removed surgically without previous chemotherapy or radiotherapy. Telomerase activity was determined using a semiquantitative polymerase chain reaction-based telomeric repeat amplification protocol (TRAP) assay. The results obtained were classified into high and low telomerase groups. Localization of expression was examined by using in situ hybridization and immunohistochemistry. The correlation between telomerase activity in lung carcinoma and clinicopathologic features, including prognosis, was investigated. Telomerase activity in lung carcinomas was detected in 107 of 115 (93%) lung carcinomas, but not in any adjacent noncancerous tissues, and was significantly higher in small cell carcinoma than in any other histologic type. This activity also was significantly higher in poorly differentiated than in well-differentiated squamous cell carcinomas and adenocarcinomas. The overall survival rate (P =.020) was significantly lower in the high telomerase group. Messenger RNAs for hTERC and hTERT were mainly detected in the cytoplasm of cancer cells by in situ hybridization, and TERT protein was localized in the nuclei of these cells by immunohistochemical staining. Determinations of telomerase activity by in situ hybridization, immunohistochemistry, and TRAP assay are useful for evaluating the diagnosis and prognosis of lung carcinomas.

Long-term cultivation of colorectal carcinoma cells with anti-cancer drugs induces drug resistance and telomere elongation: an in vitro study.

BACKGROUND: The role of telomerase activation in the expression and/or maintenance of drug resistance is not clearly understood. Therefore, we investigated the relationships, among the telomerase activity, telomere length and the expression of multidrug resistance genes in colorectal cancer cell lines cultivated with anti-cancer drugs. METHODS: LoVo and DLD-1 cells were continuously grown in the presence of both CDDP and 5-FU for up to 100 days. Cell proliferation, telomerase activity, telomere length and the expression of multidrug resistance genes were serially monitored as the PDL increased. RESULTS: The expression of multidrug resistance genes tended to increase as the PDL increased. However, an abnormal aneuploid clone was not detected as far as the cells were monitored by a DNA histogram analysis. Tumor cells showing resistance to anti-cancer drugs revealed a higher cell proliferation rate. The telomere length gradually increased with a progressive PDL. The telomerase activity reached a maximum level at 15 PDL in LoVo cells and at 27 PDL in DLD-1 cells. An increase in the mRNA expression of the telomerase components, especially in hTERT and in hTR, was observed at the same PDLs. CONCLUSIONS: These results suggest that a high telomerase activity and an elongation of telomeres both appear to help maintain and/or increase drug resistance in colorectal cancer cells. Cancer cells with long telomeres and a high proliferative activity may thus be able to better survive exposure to anti-cancer drugs. This is presumably due to an increased chromosome stability and a strong expression of both mdr-1 and MRP genes.

Acute myeloblastic leukemia associated with trisomy 8 and translocation 8;21 in a child with Down syndrome.

The present study examined an 11-year-old girl with Down syndrome who suffered from acute myeloblastic leukemia (AML) preceded by preleukemic pancytopenia. Chromosomal analysis of leukemic cells revealed a chromosome change at t(8;21) and trisomy 8 associated with constitutional trisomy 21. Treatment with antineoplastic agents led to complete remission.

Induction of apoptosis by JTE-522, a specific cyclooxygenase-2 inhibitor, in human gastric cancer cell lines.

An increased expression of cyclooxygenase (COX)-2 has been observed in various cancers including gastric cancer. Although specific COX-2 inhibitors have a chemopreventive effect on colon cancer, their molecular mechanisms remain unclear. To clarify these mechanisms, we investigated the effects of JTE-522, a newly developed COX-2-specific inhibitor, on gastric cancer cell lines (MKN28 and MKN45). The baseline levels of COX-2 expression were higher in MKN45 than in MKN28. JTE-522 obviously suppressed the levels of COX-2 mRNA, COX-2 protein and PGE2 at a dose of 250 microM in both cancer cells. Apoptosis was induced at 24 hours after treatment with JTE-522 (250 microM) in both cancer cells. To determine the mechanisms of apoptosis induction by JTE-522, the time course of the cell cycle and the apoptosis-related protein levels were examined. An increase in the G1 phase and a decrease in the S phase were observed prior to apoptosis. Moreover, an increase of c-myc protein and a decrease of bcl-2 protein were observed in both cells treated with JTE-522. These findings suggested that JTE-522 could induce apoptosis by blocking the cell cycle, enhancing c-myc expression and diminishing bcl-2 expression. JTE-522 also suppressed proliferation activity in both cell lines. These effects of JTE-522 were more dramatic in MKN45 than in MKN28. Since JTE-522 strongly suppresses cell growth by inducing apoptosis in gastric cancer cell lines, it may therefore serve as a chemopreventive agent.

Effects of neurosurgical treatment on diffuse slow spike and wave complex: a case of left frontal mass lesion with diffuse slow spike and wave complex (DSSW).

A 10-year-old girl with a mass lesion in the left deep frontal lobe was reported. Clinically, seizures occurred at 3 years and 8 months and became intractable around the age of 5.5 years. EEG initially showed focal spikes on the left fronto-central area and later developed into diffuse slow spike and wave complexes (DSSW). Her seizures were clinically different from those in Lennox-Gastaut syndrome. After a left frontal lobectomy, her intractable seizures completely disappeared with marked EEG improvement and without any neurological deficit. Radiological findings before the operation suggested that the expanding effects extended to the deep temporal structures, adjacent to the frontal lobe. These structures, deep frontal and temporal lobes, both or either, were assumed to be involved in generating DSSW in this case.

[Establishment and characterization of a human undifferentiated carcinoma cell line (HMG)].

The undifferentiated carcinoma cell line (HMG) was established from a nude mouse tumor which had been produced by transplantation of a intraperitoneal tumor of 27-year-old woman. The HMG cell line has the following biological properties. 1. The HMG cells are round to oval in shape and grow as floating cell aggregates like a rouleau or a cluster of grapes. 2. 100 passages have been carried out over a year, and the population doubling time is about 17 hrs. 3. In the original tumor, keratin and vimentin were expressed simultaneously, in HMG cells, however, only localization of vimentin was confirmed. 4. By chromosomal analysis, over 90% of the cells revealed 46, XX, with no karyological abnormalities, at passage 82. 5. When heterotransplanted into the subcutis of a nude mouse, HMG cells produced a undifferentiated carcinoma resembling the original tumor.

Telomerase activation and MAPK pathways in regenerating hepatocytes.

Although there have been many reports on the relationship between the activation of telomerase and carcinogenesis, the role of telomerase in normal cellular growth is still unclear. Recently, the telomerase upregulation during the process of liver regeneration has been reported, but the precise time course of its activity and factors contributing to the activation of telomerase have not yet been fully elucidated. In the present review, we demonstrate the relationship between the activation of the telomerase, the cell cycle progression and the growth-related signaling during the liver regeneration process using an in vivo mouse partial hepatectomy model. Moreover, the importance of the role of the MAPK pathways on the telomerase activity in regenerating hepatocytes is also displayed by using an in vitro culture model. In conclusion, the telomerase activity is upregulated before hepatocytes enter the S phase, and some growth factors such as EGF and HGF contribute to this process. The activation of the growth-related signaling pathways seems to play essential roles in the upregulation of the telomerase activity.

Adsorption and preparation of human viruses using hydroxyapatite column.

The adsorption and chromatographic properties of hydroxyapatite sorbents for application to different viruses have been investigated. The strong adsorption of viruses was observed on macroporous hydroxyapatite with hydrophilic properties of the sorbent surface. The viruses were purified on this sorbent without loss of biological activity. The column can be used for virus vaccine production.