MRP-1/CD9 and KAI1/CD82 expression in normal and various cancer tissues

As part of our evaluation of MRP-1/CD9 and KAI1/CD82 as prognostic predictors among patients with cancer, we have extended our studies to solid tumors of a variety of anatomical sites. Normal tissues were included for comparison. Immunohistochemical techniques were used throughout. Our results indicate that MRP-1/CD9 was strongly expressed by many normal tissues, including the epithelium of the gastrointestinal tract, alveolar epithelium of the lung, urothelium and smooth muscle. Expression was weak in the pituitary gland, spleen and hepatocytes, and absent in testes and spinal cord. KAI1/CD82 was also expressed by many normal tissues, but was absent in some MRP-1/CD9-positive tissues (e.g., smooth muscle, adrenal cortex, urothelium, myelin of peripheral nerves, epithelium of amnion). On the other hand, KAI1/CD82 was strongly expressed in spinal cord gray matter, which was MRP-1/CD9-negative. Expression of these glycoproteins was detected in almost all types of tumors examined. In certain cancers, MRP-1/CD9 and KAI1/CD82 positivity was inversely related to lymph node involvement. Whereas lymph node metastases were present in 22.2% of lung cancer patients whose tumors were MRP-1/CD9 and KAI1/CD82-positive, 65.5% of patients with MRP-1/CD9 and KAI1/CD82-reduced/negative tumors had lymph node metastases. A similar inverse relationship was seen in colon cancer and breast cancer patients with respect to MRP-1/CD9 expression. The present data, together with our previous results suggest that evaluating the MRP1/CD9 and KAI1/CD82 status of cancers of the lung, breast and colon may provide useful information on the metastatic potential of the tumors.

Chemokine receptor CXCR3 promotes colon cancer metastasis to lymph nodes

Chemokines and their receptors are essential for leukocyte trafficking, and also implicated in cancer metastasis to specific organs. We have recently demonstrated that CXCR3 plays a critical role in metastasis of mouse melanoma cells to lymph nodes. Here, we show that some human colon cancer cell lines express CXCR3 constitutively. We constructed cells that expressed CXCR3 cDNA ('DLD-1-CXCR3'), and compared with nonexpressing controls by rectal transplantation in nude mice. Although both cell lines disseminated to lymph nodes at similar frequencies at 2 weeks, DLD-1-CXCR3 expanded more rapidly than the control in 4 weeks. In 6 weeks, 59% of mice inoculated with DLD1-CXCR3 showed macroscopic metastasis in para-aortic lymph nodes, whereas only 14% of those with the control (P<0.05). In contrast, metastasis to the liver or lung was rare, and unaffected by CXCR3 expression. In clinical colon cancer samples, we found expression of CXCR3 in 34% cases, most of which had lymph node metastasis. Importantly, patients with CXCR3-positive cancer showed significantly poorer prognosis than those without CXCR3, or those expressing CXCR4 or CCR7. These results indicate that activation of CXCR3 with its ligands stimulates colon cancer metastasis preferentially to the draining lymph nodes with poorer prognosis.

Fish otolith asymmetry: Morphometry and modeling

Mathematical modeling suggests that relatively large values of otolith mass asymmetry in fishes can alter acoustic functionality and may be responsible for abnormal fish behavior when subjected to weightlessness during parabolic or space flight [D.V. Lychakov, Y.T. Rebane, Otolith mass asymmetry in 18 species of fish and pigeon, J. Grav. Physiol. 11 (3) (2004) 17-34; D.V. Lychakov, Y.T. Rebane, Fish otolith mass asymmetry: morphometry and influence on acoustic functionality, Hear. Res. 201 (2005) 55-69]. The results of morphometric studies of otolith mass asymmetry suppose that the absolute value and the sign of the otolith mass asymmetry can change many times during the growth of individual fish within the range +/-20% [D.V. Lychakov, Y.T. Rebane, Otolith mass asymmetry in 18 species of fish and pigeon, J. Grav. Physiol. 11 (3) (2004) 17-34; D.V. Lychakov, Y.T. Rebane, Fish otolith mass asymmetry: morphometry and influence on acoustic functionality, Hear. Res. 201 (2005) 55-69]. This implies that the adverse effects of otolith asymmetry on acoustic and vestibular functionality could change during the lifetime of an individual fish. The aims of the present article were to examine the nature of otolith mass asymmetry fluctuation and to quantify otolith mass asymmetry in a large number of teleost fishes to verify our previous measurements. A dimensionless measure of otolith mass asymmetry, chi, was calculated as the difference between the masses of the right and left paired otoliths divided by average otolith mass. Saccular otolith mass asymmetry was studied in 59 Mediterranean teleost species (395 otolith pairs), 14 Black Sea teleost species (42 otolith pairs), red drum (196 otolith pairs) and guppy (30 otolith pairs). Utricular otolith mass asymmetry was studied in carp (103 otolith pairs) and goldfish (45 otolith pairs). In accordance with our previous results the value of chi did not depend on fish size (length or mass), systematic or ecological position of the fish, or otolith growth rate. In the great majority of the fishes studied, the saccular otolith chi was small /chi/ <0.05 (or <5%). Mathematical modeling indicates that values of chi vary among individual fish, but that the value is probably stable during a fish's lifetime.

Clinical significance of transmembrane 4 superfamily in colon cancer

Cell motility is an important cellular function closely related to the processes of tumour progression and metastasis. Several members of transmembrane 4 superfamily (TM4SF) have been reported to be associated with cell motility and metastatic potential of solid tumour. The aim of this study is to clarify the clinical significance of the member of TM4SF (MRP-1/CD9, KAI1/CD82 and CD151) in human colon cancer. We studied 146 colon cancer patients who underwent curative surgery and studied the expression of MRP-1/CD9, KAI1/CD82 and CD151 using reverse transcriptase - polymerase chain reaction and immunohistochemistry. We found that 64 patients (43.8%) had MRP-1/CD9-positive tumours and that the overall survival rate of patients with MRP-1/CD9-positive tumours was much higher than that of patients with MRP-1/CD9-negative tumours (89.8 vs 50.8%, P<0.001). In contrast, 63 patients (43.2%) had KAI1/CD82-positive tumours and the overall survival rate of patients with KAI1/CD82-positive tumours was also higher than that of patients with KAI1/CD82-negative tumours (84.8 vs 54.9%, P=0.002). On the other hand, positive CD151 expression had a bad effect on the overall survival rate of patients with colon cancer (61.2 vs 74.9%, P=0.022). In a multivariate analysis, MRP-1/CD9 status was a good indicator of the overall survival (P=0.007). We have shown that the reduction of MRP-1/CD9 and KAI1/CD82 expression, and the increasing CD151 expression are indicators for a poor prognosis in patients with colon cancer. This is a first report describing about the relation between CD151 and colon cancer.

Changes of vertical eye movements of goldfish for different otolith stimulation by linear acceleration

Eye movements serves to hold the gaze steady or to shift the gaze to an object of interest. On Earth, signals from otoliths can be interpreted either as linear motion or as tilt with respect to gravity. In microgravity, static tilt will no longer give rise to changes in otolith activity. However, linear acceleration as well as angular acceleration stimulate the otolith organ. Therefore, during adaptation to microgravity, otolith-mediated response such as eye movements alter. In this study, we analyzed the eye movements of goldfish during linear acceleration. The eye movements during rectangular linear acceleration along the different body axis were video-recorded. The vertical eye rotations were analyzed frame by frame. In normal fish, leftward lateral acceleration induced downward eye rotation in the left eye and upward eye rotation in the right eye. Acceleration from caudal to rostral evoked downward eye rotation in both eyes. When the direction of acceleration was shifted 15 degrees left, the responses in the left eye disappeared. These results suggested that otolith organs in each side were stimulated differently.

Modulation of intracellular glutathione concentration alters dehydropyrimidine dehydrogenase activity in peripheral blood mononuclear cells

Dehydropyrimidine dehydrogenase (DPD) is the initial key enzyme in the regulation of 5-fluorouracil catabolism and thus controls availability of 5-fluorouracil for anabolism. Modulation of DPD activity may increase the antitumor effect and avoid toxic side effects in 5-fluo-rouracil-based chemotherapy. We measured DPD activity in peripheral blood mononuclear cells from cancer patients and simultaneously monitored intracellular glutathione (GSH) and plasma GSH levels. There was a significant linear relationship between DPD activity and intracellular GSH levels in peripheral blood mononuclear cells obtained from cancer patients. Suppression of intracellular GSH level by buthionine sulfoximine decreased DPD activity, while enhancement of intracellular GSH level by 2-mercaptoethanol increased DPD activity. This study indicated that alteration of intracellular GSH concentration may modulate DPD activity.

Relationship between head orientation and torsional eye movements in goldfish during linear acceleration

We analyzed torsional eye movements of normal goldfish during sinusoidal linear acceleration, altering the orientation of the fish on the linear accelerator in the yaw plane over a range of 90 degrees and in the pitch plane up to 30 degrees. We video-recorded changes of torsional eye movements associated with a body rotation in the yaw and pitch plane and analyzed them frame by frame. In normal fish, we observed clear torsional eye movements for stimuli of 0.1 G linear accelerations along the body axis in the horizontal position. Torsion occurred in the opposite direction of resultant force produced by linear acceleration and gravity. Though the amplitude of these compensatory responses increased with increasing magnitude of acceleration up to 0.5 G, the torsion angle did not fully compensate the angle calculated from gravity and linear acceleration. Furthermore, the torsion angle decreased as the longitudinal body axis deviated from the direction of linear acceleration. For the body axis perpendicular to the direction of acceleration, torsional eye movement was still observed. When we tilted the fish in the pitch plane, compensatory eye torsion occurred. The response amplitude to acceleration decreased for both head-up and head-down up to 30 degrees. These results suggested the existence of specific connections between the otolith organ and ocular muscles.

[Total removal of infected pacemaker lead under cardiopulmonary bypass in a case of endocarditis, bacteremia and lung abscess]

A 60-year-old man, who had undergone implantation of a transvenous pacemaker system on the left chest wall for sick sinus syndrome 19 years ago, was admitted because of endocarditis with septicemia and lung abscess 2 months after reimplantation of the generator. His blood culture revealed Staphylococcus aureus. Following debridement of the infected pacemaker pocket and antibiotics therapy, we tried to remove the pacemaker system under cardiopulmonary bypass 1 month after admission. In intraoperative inspection, the electrodes had become firmly encased with fibrous tissue within the tricuspid valve and the right ventricle. After the operation, antibiotic therapy was performed for 4 weeks. His postoperative course was uneventful. Patients with pacemaker infection should undergo aggressive total removal of the pacemaker system, particularly incase with endocarditis and bacteremia.

Compartmentalization of Peyer's patch anlagen before lymphocyte entry

We have shown that Peyer's patch (PP) first develops as a simple and even cell aggregation during embryogenesis. To investigate when and how such a simple cell aggregation forms the complex PP architecture, we analyzed the distribution of cells expressing IL-7R alpha (PP inducer cells), VCAM-1 (mesenchymal cells), CD11c (dendritic cells), and mature lymphocytes by whole-mount immunostaining of 17.5 days post coitus to 2 days postpartum mouse gut. Our results show that compartmentalization of PP anlagen commences at day 18.5 of gestation by clustering and subsequent follicle formation of IL-7R alpha(+), VCAM-1(+), and CD11c(+) cells. This process adds the primitive architecture of PP anlage with several follicles in which IL-7R alpha(+) cells localize in the center, while VCAM-1(+) and CD11c(+) cells localize at the fringe. This follicle formation is accompanied by the establishment of PP-specific vascular network expressing mucosal addressin cellular adhesion molecule-1. Mature B and T lymphocytes entering in the PP anlage are distributed promptly to their own target zones; B cells to the follicle and T cells to nonfollicular zones. Our analysis of scid/scid mouse indicate that the initial processes including formation of PP-specific vascular network occur in the absence of lymphocytes. These observations indicate that the basic architecture of PP is formed by a set of cell lineages assembled during the initial phase of induction of PP anlagen before entry of mature lymphocytes.

Association of IFN-gamma and IFN regulatory factor 1 polymorphisms with childhood atopic asthma

BACKGROUND

IFN-gamma and related molecules play important roles in the differentiation and function of TH2 cells.

OBJECTIVE

We sought to determine whether IFNG and related genes contribute to any susceptibility to atopic asthma, a representative TH2-dominant disorder.

METHODS

We investigated the association of IFNG (CA repeat polymorphism within the first intron), IRF1 (GT repeat polymorphism within the intron 7), IFNGR1 (Val 14 Met), and IFNGR2 (Gln 64 Arg) gene polymorphisms with atopic asthma in the Japanese child population.

RESULTS

A significant association (P =.0018) was observed between IFNG gene polymorphism and atopic asthma. The tendency was more prominent in patients with age of onset of 3 years or younger (P =.0004) or patients with a family history of allergic diseases (P =.0038). Furthermore, there was a significant association between IRF1 gene whole-allele distribution and atopic asthma (P =.044). The tendency was more prominent in patients with onset at 3 years of age or less (P =.0058). On the other hand, IFNGR1 and IFNGR2 gene polymorphisms showed no association with atopic asthma.

CONCLUSION

These results suggested that among IFNG and related genes, IFNG and IRF1 genes confer genetic susceptibility to atopic asthma in Japanese children.

Lack of association between CD28/CTLA-4 gene polymorphisms and atopic asthma in the Japanese population

Atopic asthma occurs in genetically susceptible individuals in the presence of environmental factors. Recently, the costimulation signal from CD80-CD86 to CD28/CTLA-4 has been suggested to play an important role in the development of atopic asthma. In the present study, we analyzed three polymorphic regions within the CTLA-4 gene, an A/G substitution in exon 1 position 49, a C/T base exchange in the promoter position -318 and an (AT)n repeat polymorphism in the 3'-untranslated region of exon 4, and a CD28 gene polymorphism with a T/C substitution in intron 3 position +17 in 120 patients with atopic asthma and 200 normal controls. The polymorphism frequencies of CTLA-4/CD28 genes in patients did not differ from those in normal controls. Thus, the present study was unable to reveal any association between CTLA-4/CD28 gene polymorphisms and atopic asthma in the Japanese population.

The novel monoclonal antibody MH8-4 inhibiting cell motility recognizes integrin alpha 3: inverse of its expression withmetastases in colon cancer

The molecular basis of cell motility is obviously highly complex and is considered to be controlled by a number of molecular systems including cell adhesion molecules, their receptors, cytoskeletal components, a junctional unit connecting cytoskeletal components and membrane receptors, and various peptide growth factors. The possible involvement of proteins at the cell surface in controlling cell motility has been systematically investigated. Previously, we have addressed this question using functional monoclonal antibodies (MAbs), which inhibit cell motility as probes. In order to further identify cell surface molecules involved in metastasis of gastrointestinal tumors, the present study utilized an approach based on the selection of a colon cancer cell line RPMI4788, which showed high motility out of a large number of human gastrointestinal tumor cell lines. MAb MH8-4 was established after immunization of mice with RPMI4788 and selected on the basis of inhibition of RPMI4788 cell migration in a transwell penetration assay. MH8-4 inhibited the phagokinetic tract motility of various cancer cell lines. A cDNA cloning revealed that MH8-4 recognized a specific protein structure, integrin alpha 3. In order to determine whether these experimental results are of relevance with respect to actual human gastrointestinal tumors, we investigated integrin alpha 3 expression in 40 colon cancers with distant metastases. Our immunohistochemical study showed that in almost 27.5% of the cases, the metastatic tumors had lower integrin alpha 3 levels than their corresponding primary tumors. Moreover, there were no primary tumors with lower integrin alpha 3 expression than their corresponding metastatic tumors. Our data suggest that low integrin alpha 3 expression may be associated with the metastatic potential of certain colon cancers.

Dihydropyrimidine dehydrogenase activity and mRNA expression in advanced gastric cancer analyzed in relation to effectiveness of preoperative 5-fluorouracil-based chemotherapy

Dihydroxypyrimidine dehydrogenase (DPD) is an enzyme involved in degradation and inactivation of 5-fluorouracil (5-FU). The amount of its expression in a tumor is thought to be a factor determining the response of the tumor to 5-FU therapy. We compared DPD activity and DPD mRNA expression in resected tumors between two groups of patients, i.e., a group of 14 patients with advanced gastric cancer who received preoperative chemotherapy (neoadjuvant chemotherapy; NAC) and surgery and a group of 24 patients with advanced gastric cancer who underwent surgery without preoperative chemotherapy. Tumor DPD activity was found to correlate well with tumor DPD mRNA expression. In the surgery alone group, DPD activity decreased significantly as the tumor stage advanced. This change was not observed in the NAC plus surgery group. Neither tumor depth (T factor) nor lymph node metastasis was found to correlate with DPD activity. Patients who responded to preoperative chemotherapy had lower DPD mRNA levels. Based on these results, we anticipate that measurement of DPD expression in clinical specimens may be clinically useful in managing advanced gastric cancer.

Childhood atopic asthma: positive association with a polymorphism of IL-4 receptor alpha gene but not with that of IL-4 promoter or Fc epsilon receptor I beta gene

We examined the relative contributions of three representative candidate genes for atopy (Fc epsilon receptor I beta, IL-4, and IL-4 receptor alpha) to the development of atopic asthma. Four polymorphisms of the three candidate genes including Ile50Val and Gln551Arg of IL-4 receptor alpha, -590C/T of IL-4 promoter and Glu237Gly of Fc epsilon receptor I beta were studied in 100 patients with atopic asthma and 100 nonatopic controls in the northern Kyushu area in Japan. Among the four polymorphisms of the three candidate genes, the Ile50 allele of the IL-4 receptor alpha chain gene demonstrated an association with atopic asthma subjects (p = 0.044), especially in patients with onset at 2 years of age or earlier (p = 0.034) and in patients with moderate to severe atopic asthma (p = 0. 031). Gln551Arg of IL-4 receptor alpha, -590C/T of IL-4 promoter and Glu237Gly of Fc epsilon receptor I beta showed no association with atopic asthma. A slight linkage disequilibrium between Ile50Val and Gln551Arg polymorphisms of the IL-4 receptor alpha chain gene was observed in both patients and nonatopic controls. The identification of additional atopy genes in areas with a certain genetic background is essential for genetic diagnosis and to establish new therapeutic modalities for atopic asthma.

Involvement of vascular endothelial growth factor receptor-3 in maintenance of integrity of endothelial cell lining during tumor angiogenesis

Vascular endothelial growth factor (VEGF) plays a major role in tumor angiogenesis. VEGF-C, however, is thought to stimulate the growth of lymphatic vessels because an expression of its specific receptor, VEGF receptor-3 (VEGFR-3), was demonstrated to be restricted to lymphatic vessels. Here we demonstrate that the inactivation of VEGFR-3 by a novel blocking monoclonal antibody (mAb) suppresses tumor growth by inhibiting the neo-angiogenesis of tumor-bearing tissues. Although VEGFR-3 is not expressed in adult blood vessels, it is induced in vascular endothelial cells of the tumor-bearing tissues. Hence, VEGFR-3 is another receptor tyrosine kinase involved in tumor-induced angiogenesis. Micro-hemorrhage in the tumor-bearing tissue was the most conspicuous histologic finding specific to AFL4 mAb-treated mice. Scanning microscopy demonstrated disruptions of the endothelial lining of the postcapillary venule, probably the cause of micro-hemorrhage and the subsequent collapse of the proximal vessels. These findings suggest the involvement of VEGFR-3 in maintaining the integrity of the endothelial lining during angiogenesis. Moreover, our results suggest that the VEGF-C/VEGFR-3 pathway may serve another candidate target for cancer therapy. (Blood. 2000;96:546-553)

Expression of thioredoxin and glutaredoxin, redox-regulating proteins, in pancreatic cancer

Pancreatic cancer (pancreatic ductal carcinoma) is one of the most malignant solid tumors with poor prognosis. There is accumulating evidence that cellular reduction/oxidation (redox) status is deeply involved in the growth promotion and drug resistance of cancer cells. We therefore investigated the expression of redox-regulating proteins, such as thioredoxin (TRX) and glutaredoxin (GRX) in surgically resected pancreatic tissues and cis-diamminedichloroplatinum (CDDP)-resistant cells. Plasma levels of TRX were also measured in subjects with pancreatic diseases. Pancreatic ductal carcinoma tissues were immunohistochemically more positive for TRX (24/32 cases) and GRX (29/32 cases) than pancreatic cystadenocarcinoma or normal pancreas tissues. Plasma levels of TRX (mean +/- SD) measured by ELISA were significantly higher in patients with pancreatic ductal carcinoma (54.8 +/- 37.6 ng/ml, n = 60) than in healthy controls (24.4 +/- 12.9 ng/ml, n = 81). CDDP-resistant subclones of HeLa cells, HeLa-CP5 cells, had higher expression of TRX (1.5 fold) and GRX (1.6 fold) compared with parental HeLa cells by immunoblotting. These results indicate the possible association of TRX and GRX with malignant potential of pancreatic ductal carcinoma.

Nitric oxide induces a decrease in the mitochondrial membrane potential of peripheral blood lymphocytes, especially in natural killer cells

Increased levels of nitric oxide (NO) at an inflammatory site may affect the biological activity of lymphoid cells. To investigate the effects of NO on the immune system, we measured the mitochondrial membrane potential (delta psi m) of the peripheral blood lymphocytes (PBL) cultured with a chemical NO donor. PBL from healthy volunteers were cultured with NOC18, a NO-generating compound, at various concentrations. The delta psi m of the PBL was measured by flow-cytometry using 3,3-dihexyloxacarbocyanine iodide (DiOC6(3)). NOC18 induced a decrease in the delta psi m of the PBL in a dose-dependent fashion, induced an increase in the levels of reactive oxygen species (ROS), and caused these cells to undergo apoptosis. Dual-color staining of the delta psi m and lymphocyte surface markers demonstrated that CD3-CD56+ natural killer (NK) cells were responsive to NO. Trolox, a vitamin E analog, partially reversed the NO-induced decrease in the delta psi m of the PBL. We showed that the delta psi m of peripheral NK cells were decreased by NO, which suggests that abundant NO at an inflammatory site may impair NK cell function.

Secretion of thioredoxin enhances cellular resistance to cis-diamminedichloroplatinum (II)

Thioredoxin (TRX) is a redox-active protein induced by a variety of stress and secreted from cells. Collecting evidence revealed that extracellular TRX shows cytokine- and chemokine-like activities. In the present study, we studied the role of secreted TRX on cellular resistance to cis-diamminedichloroplatinum (II) (CDDP). The CDDP-resistant variants of HeLa cells not only have enhanced expression of intracellular TRX, but also show increased secretion of TRX into the culture medium, compared to the parental cells. The CDDP-resistant cells also exhibit an enhanced L-cystine uptake capability, which results in a significant increase in the intracellular sulfhydryl content, including glutathione (GSH). Exogenous administration of recombinant TRX (rTRX) increases cellular resistance to CDDP and augments the L-cystine uptake in the parental HeLa cells. Moreover, depletion of L-cystine from the culture medium or combined treatment with L-cystine uptake inhibitors increases cellular sensitivity to CDDP in the CDDP-resistant cells. These findings suggest that secreted TRX may play an important role in the acquisition of cellular CDDP resistance through enhancement of the L-cystine uptake activity, and that the L-cystine transport system, as well as the TRX system, may be a novel therapeutic target in CDDP-resistant cancer cells.

Novel polymorphism in the 5'-untranslated region of the interleukin-4 gene

We found a novel polymorphism C/T change at position -34 counting from the first ATG codon, of the interleukin-4 (IL-4) gene, located between the TATA box and the first ATG on exon 1. The allelic frequency of this C/T polymorphism in 64 independent Japanese samples was 0.37:0.63. In addition, PCR-restriction fragment length polymorphism analysis revealed that the -34T/T polymorphism was always associated with -590T/T, a known polymorphism that increases IL-4 transcriptional activity.

Possible involvement of thioredoxin reductase as well as thioredoxin in cellular sensitivity to cis-diamminedichloroplatinum (II)

The thioredoxin (TRX) system, composed of nicotinamide adenine dinucleotide phosphate (reduced form), TRX, and TRX reductase (TRXR), has multiple biologic functions via thiol-mediated redox control. In this study, we investigated the relationship between intracellular TRXR levels and cellular sensitivity to cis-diamminedichloroplatinum (II) (CDDP). HeLa, a human cervical carcinoma cell line, cultured with CDDP showed a time- and dose-dependent reduction of intracellular TRXR activity, which was well correlated with the decrease in cell viability after exposure to CDDP. In a cell-free system, CDDP was found to directly inactivate the reduced form of purified human TRXR. The CDDP-resistant variants of HeLa cells, established by continuous exposure to CDDP, exhibited an increased expression and activity of TRXR as well as TRX compared with the parental cells. In addition, sodium selenate, an inhibitor of TRXR, was found to increase the susceptibility to CDDP in the CDDP-resistant cells. Moreover, the HeLa cells transfected with an antisense TRXR RNA expression vector to reduce the intracellular enzyme activity displayed an enhanced sensitivity to CDDP. Taken together with previous reports on TRX, these results indicate the possible involvement of TRXR as well as TRX in the cellular sensitivity and resistance to CDDP.

The role of chloroplastic NAD(P)H dehydrogenase in photoprotection

After a brief exposure to supra-saturating light, leaves of a tobacco transformant, in which chloroplastic NAD(P)H dehydrogenase (NDH) was defective, showed more severe photoinhibition than the wild-type, when judged by the parameter of chlorophyll fluorescence Fv/Fm. Repeated application of supra-saturating light eventually resulted in chlorosis in the NDH-defective mutant, while the wild-type sustained less photodamage and was able to recover from it. The mechanism of the phenomena is discussed with respect to the potential role of NDH in photosynthesis.

Induction of smooth muscle cells in the fibrous capsule of human hepatocellular carcinoma but not in the septa of hepatic cirrhosis

We examined the expression of smooth muscle cytoskeleton in spindle-shaped cells in the capsule of hepatocellular carcinoma (HCC) and the septa of liver cirrhosis (LC). Serial sections of livers resected from 11 patients were stained with monoclonal antibodies against vimentin, desmin, smooth muscle actin (1A4, HHF35, CGA7) and smooth muscle myosin heavy chain isoforms (SM1, SM2). Capsular spindle-shaped cells exhibited a cytoskeletal feature indicative of intermediately differentiated smooth muscle cells. Computer-assisted morphometry revealed that the proportions of 1A4-, HHF35-, CGA7- and SM1- positive areas to vimentin-positive area were 88.0+/-11.0%, 50.8+/-17.4%, 25.3+/-16.4% and 19.4+/-12.4% (n=11) in main tumours and 86.6+/-9.4%, 50.9+/-18.7%, 21.1+/-12.3% and 17.6+/-9.7% (n=12) in daughter tumours, indicating that spindle-shaped cells are heterogeneous in cytoskeletal expression. Septal spindle-shaped cells in LC lacked the cytoskeletal proteins specific to differentiated smooth muscle cells (CGA7, SM1, SM2 and desmin). Electron microscopically, capsular spindle-shaped cells contained more microfilaments and less rough endoplasmic reticulum than do septal cells. Intermediately differentiated smooth muscle cells are induced in the capsule of HCC but not in the septa of LC, suggesting a role for stromal interaction by tumour cells in the induction of smooth muscle cells.

Effects of linear acceleration on fish behavior and eye movements

Behavioral responses and eye movements of fish during linear acceleration were reviewed. It is known that displacement of otoliths in the inner ear leads to body movements and/or eye movements. On the ground, the utriculus of the vestibular system is stimulated by otolith displacement caused by gravitational and inertial forces during horizontal acceleration of whole body. When the acceleration is imposed on the fish's longitudinal axis, the fish showed nose-down and nose-up posture for tailward and noseward displacement of otolith respectively. These responses were understood that the fish aligned his longitudinal body axis in a plane perpendicular to the direction of resultant force vector acting on the otoliths. When the acceleration was sideward, the fish rolled around his longitudinal body axis so that his back was tilted against the direction in which the inertial force acted on the otoliths. Linear acceleration applied to fish's longitudinal body axis evoked torsional eye movement. Direction of torsion coincided with the direction of acceleration, which compensate the change of resultant force vector produced by linear acceleration and gravity. Torsional movement of left and right eye coordinated with each other. In normal fish, both sinusoidal and rectangular acceleration of 0.1G could evoke clear eye torsion. Though the amplitude of response increased with increasing magnitude of acceleration up to 0.5 G, the torsion angle did not fully compensate the angle calculated from gravity and linear acceleration. Removal of the otolith on one side reduced the response amplitude of both eyes. The torsion angle evoked by rectangular acceleration was smaller than that evoked by sinusoidal acceleration in both normal and unilaterally labyrinthectomized fish. These results suggest that eye torsion of fish include both static and dynamic components.

Prognostic significance of angiogenesis in human pancreatic cancer

To evaluate whether angiogenic factors are of clinical relevance to actual human pancreatic cancers, we studied the intratumoral microvessel density (IMD), and PD-ECGF, VEGF protein expression in 40 pancreatic cancers using immunohistochemistry. We also investigated PD-ECGF and VEGF gene expression using reverse transcriptase-PCR (RT-PCR). Of the 40 pancreatic cancers studied, 30 carcinomas (75.0%) were evaluated to be PD-ECGF-positive and 10 carcinomas (25.0%) were determined to be PD-ECGF-negative. In contrast, 27 carcinomas (67.5%) were evaluated to be VEGF-positive, whereas 13 carcinomas (32.5%) were VEGF-negative. VEGF gene expression was moderately associated with an increase in the IMD (r2 = 0.181, P = 0.006), but no significant relationship was found between PD-ECGF gene expression and the IMD (r2 = 0.093, P = 0.059). However, tumours with positive expression for both PD-ECGF and VEGF had a higher IMD (P = 0.027). The results of the immunohistochemistry agreed well with the results of the quantitative RT-PCR. The median survival time of the hypervascular group was significantly shorter than that of the hypovascular group (P < 0.0001). In comparing the survival according to PD-ECGF and VEGF gene expression, the median survival time of the patients with positive PD-ECGF expression was significantly shorter than those with negative PD-ECGF expression (P = 0.040). Furthermore, the median survival time of the patients with positive VEGF expression was significantly shorter than those with negative VEGF expression (P = 0.048). However, the Cox multivariate analysis indicated that the IMD and VEGF expression were independent prognostic factors of the various clinicopathologic variables in pancreatic cancer patients (P = 0.0021 and P = 0.0443, respectively).

Cutting edge: dominant effect of Ile50Val variant of the human IL-4 receptor alpha-chain in IgE synthesis

Two variants of the IL-4R alpha-chain (IL-4Ralpha) gene have been recently identified in association with different atopic disorders. To clarify the etiological relationship between the two variants, we analyzed responsiveness to IL-4 of transfectants with four kinds of IL-4Ralpha carrying either Val or Ile at 50 and either Gln or Arg at 551. The substitution of Ile for Val augmented STAT6 activation, proliferation, and transcription activity of the Iepsilon promoter by IL-4, whereas that of Arg for Gln did not change these IL-4 signals. Arg551 was not associated with atopic asthma in the Japanese population. CD23 expression and IgE synthesis by IL-4 were augmented in Ile50-bearing PBMC, compared with those bearing Val50. Taken together, substitution of Arg551 does not enhance the IL-4 signal for generation of germline epsilon transcript, whereas the substitution of Ile50 contributes to enhancement of IgE synthesis.

Redox regulation of caspase-3(-like) protease activity: regulatory roles of thioredoxin and cytochrome c

Oxidative stress induces a variety of cellular responses, including apoptosis, and caspase family proteases are known to be involved in apoptosis. Caspase-3(-like) protease activity was examined in Jurkat T cells to investigate the mechanism of apoptosis induced by a thioloxidant, diamide. Caspase-3 was activated when cells were cultured with 200 microM diamide that induced apoptosis, whereas no caspase-3 activation was detected with 500 microM diamide that induced necrosis. When apoptosis was induced in cells with exposure to 200 microM diamide, the intracellular thioredoxin (TRX) levels were maintained and the intracellular generation of reactive oxygen intermediates was marginal. The cytosolic fractions of cytochrome c were increased earlier than the activation of caspase-3. In contrast, when cells were exposed to 500 microM diamide, intracellular reactive oxygen intermediate generation was increased and processing of caspase-3 was not detected despite cytochrome c release, resulting in necrosis. Caspase-3 activity in cell lysate precultured with anti-Fas Ab was suppressed dose dependently by diamide and restored by thiol-reducing agents, DTT or TRX. When cells were precultured with 5 mM of buthionine sulfoximine, an inhibitor of glutathione synthesis, intracellular TRX levels were maintained, and as low as 20 microM diamide could induce apoptosis associated with the increase of cytosolic cytochrome c and the activation of caspase-3. These results indicate that the activation of caspase-3 in diamide-induced apoptosis is mediated, at least partly, by cytochrome c release from mitochondria, and the cellular reducing environment maintained by TRX, as well as glutathione, is required for caspase-3 activity to induce apoptosis.

Accumulation of stress protein 72 (HSP72) in muscle and spleen of goldfish taken into space

Using Western blot analysis, here, we report the levels of HSP72 in several organs from goldfish which were taken into space on the NASA space shuttle. A remarkable accumulation of HSP72 was detected in muscle and spleen of those fish taken into space as compared with controls. These results suggested that the HSP72 induction is a kind of stress response at the molecular level introduced by the space environment consisting of microgravity and/or cosmic radiation as stressors.

Mechanism of vestibular adaptation of fish under microgravity

In a space experiment, the adaptation of goldfish behavior during flight and readaptation after landing were investigated. Six goldfish (1 normal, 1 with otoliths removed on both sides, 4 with otoliths removed on one side) were flown in a fish package (F/P) of Aquatic Animal Experiment Unit (AAEU). The dorsal light responses (DLRs) of fish with otoliths removed were recorded after operation until launch and after landing. The behaviors of the fish were recorded with a video camera on Mission Elapsed Time (MET) Day-00, 02, 05, 08, 12. On MET Day-00, two fish with otoliths removed on one side showed flexion of body toward the operated side. These fish also showed rolling behavior toward the operated side. However, the body flexion disappeared on MET Day-05 or MET Day-08. No rolling behaviors were observed after that time. Five fish showed backward looping behaviors during the mission. Although the frequency of looping episodes decreased after MET Day-08, five fish still showed looping behavior on MET Day-12, that was the last day of video recording on orbit. In microgravity, visual system of fish did not seem to provide sufficient cues to prevent them from looping or rolling. After landing, no looping and rolling behavior was observed. However, the tilt angle of the DLR increased in the fish with otolith removed 5 month before launch but not in normal fish and those with otoliths removed 2 weeks before launch. These results suggest that the behavioral dysfunction and the adaptational process in space are dependent on vestibular inputs.

Breast milk is not a significant source for early Epstein-Barr virus or human herpesvirus 6 infection in infants: a seroepidemiologic study in 2 endemic areas of human T-cell lymphotropic virus type I in Japan

In order to evaluate the possibility of Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6) transmission via breast milk, a total of 331 serum specimens collected from bottle-fed and breast-fed children and their mothers, in 2 endemic areas of human T-cell lymphotropic virus type I (HTLV-I) in Japan, were assayed for antibodies to EBV and HHV-6. The seroprevalences of EBV and HHV-6 were over 95% both in the mothers of bottle-fed children and in those of breast-fed children. The seroprevalence of EBV at 12-23 months of age was 54.5% (36/66) and 55.8% (24/43) in breast-fed children and bottle-fed children, respectively. The seroprevalence of HHV-6 at 12-23 months of age was 90.9% (60/66) and 93.0% (40/43) in breast-fed children and bottle-fed children, respectively. No difference was observed between the seroprevalences of EBV and HHV-6 in breast-fed and bottle-fed children at 12-23 months of age. Our seroepidemiologic data indicate that breast milk is not a significant source of early EBV or HHV-6 infection in infancy.

Redox control of resistance to cis-diamminedichloroplatinum (II) (CDDP): protective effect of human thioredoxin against CDDP-induced cytotoxicity

Thioredoxin is a small ubiquitous protein with multiple biological functions, including cellular defense mechanisms against oxidative stress. In the present study, we investigated the role of human thioredoxin (hTRX) in the acquisition of cellular resistance to cis-diamminedichloroplatinum (II) (CDDP). The expression and activity of hTRX in Jurkat T cells was dose-dependently enhanced by exposure to CDDP, as determined by immunoblot analysis and insulin reducing assay. Furthermore, chloramphenicol acetyltransferase analysis using the hTRX promoter-reporter gene construct revealed that treatment of Jurkat cells with CDDP caused transcriptional activation of the hTRX gene, which might be mediated through increased generation of intracellular reactive oxygen intermediates. To examine the biological significance of hTRX induction, we established hTRX-overexpressing derivatives of L929 fibrosarcoma cells by stable transfection with the hTRX cDNA. The clones, which constitutively expressed the exogenous hTRX, displayed increased resistance to CDDP-induced cytotoxicity, compared with the control clones. After exposure to CDDP, the control cells showed a significant increase in the intracellular accumulation of peroxides, whereas the hTRX-transfected cells did not. Taken together, these results suggest that overexpressed hTRX is responsible for the development of cellular resistance to CDDP, possibly by scavenging intracellular toxic oxidants generated by this anticancer agent.

Evidence of sensory conflict and recovery in carp exposed to prolonged weightlessness

BACKGROUND

Evidence in support of the sensory conflict hypothesis for space motion sickness (SMS) is still needed.

HYPOTHESIS

We hypothesized that sensory conflict and recovery processes should be demonstrated in intact fish during initial days of microgravity exposure, as a disturbance and restoration of the dorsal light response (DLR; a functional model of visual-graviceptor interaction), respectively. We also expected that this would be true in an otolith-removed fish if it had been fully compensated for dysfunction before the exposure.

METHODS

The DLR of carp (Cyprinus carpio) was examined intermittently during the 8-d mission of Spacelab-J. Two carp, normal and labyrinthectomized (LB), made the flight.

RESULTS

In the normal carp, the DLR was unstable for the first 3 d inflight but gradually recovered thereafter. The recovery was characterized by gradual restoration of the DLR tilt speed. The LB fish whose otoliths had been removed 2 mo before the flight maintained DLR at the first inflight test session (22 h after launch), but DLR was disrupted at 2 d as in normal fish. The recovery process could not be evaluated in this fish, because the EEG cable which was attached to the fish for supplementary study became tightly twisted and thus immobilized the fish for the remainder of the experiment.

CONCLUSION

These findings provided additional evidence in fish for sensory-motor disorder and readjustment during the early phase of microgravity, thus supporting the sensory conflict hypothesis for SMS.

The looping behavior of fish in microgravity

Fish subjected to microgravity during space flight were monitored for their swimming behavior, particularly the looping response. Experiments were performed on normal fish, unilaterally labyrinthectomized fish, and bilaterally labyrinthectomized fish. Observation were compared against the behavior of other species which had been evaluated in microgravity during parabolic flight.

Biliary haptoglobin, a potent promoter of cholesterol crystallization at physiological concentrations

BACKGROUND/AIMS

Several proteins present in human bile have been reported to promote cholesterol crystallization and thus are potentially important in the formation of cholesterol crystals as the initial stage in gallstone pathogenesis. To be physiologically relevant, such proteins must either be present in high concentration in bile or have a potent promoting activity. The current study explored several of the more abundant but unexamined biliary proteins based upon their also having sufficiently high serum concentrations that antibodies were available for both their isolation and quantitation.

METHODS

Protein purification was accomplished by immunoaffinity chromatography of bile followed by delipidation. Con A affinity chromatography of bile was used to obtain the bound fraction, a portion of which was delipidated. Crystallization-promoting activity of both the purified proteins and Con A-bound glycoprotein fractions (CABG) was measured by a photometric crystal growth assay. A competitive antibody-capture ELISA assay was developed to measure concentrations of alpha 1-antitrypsin, transferrin, and haptoglobin in native bile.

RESULTS

At their relevant physiological concentrations, biliary haptoglobin (15 micrograms/ml) had a crystallization-promoting activity twice that of the biliary IgM (75 micrograms/ml) used as a reference standard (P < 0.05). Biliary transferrin (20 micrograms/ml) had only modest promoting activity (P < 0.05). Biliary alpha 1-antitrypsin (50 micrograms/ml), by contrast, showed no promoting activity. Delipidation of the CABG fraction decreased its promoting activity by 75%. Biliary haptoglobin accounts for about 30% of delipidated total CABG-promoting activity.

CONCLUSIONS

Biliary haptoglobin at its physiological concentration has a highly potent crystallization-promoting activity and thus becomes a candidate for major attention in understanding gallstone pathogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)

The ratio of reduced glutathione/oxidized glutathione is maintained in the liver during short-term hepatic hypoxia

Controversy persists as to whether reperfusion-induced injuries actually occur in the hepatocyte. The liver is the major source of glutathione, a scavenger of hydrogen peroxide. The aim of this study was to evaluate the sensitivity of the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) [GSH:GSSG] as an index of hepatic metabolic stress. A total of 121 rats were studied. The superior mesenteric vein (SMV) was occluded for 30 min, and this was followed by 0, 10, or 120 min of reperfusion. Total glutathione and GSSG levels in the liver, bile, and plasma were quantified, using glutathione reductase-coupled enzymatic assays. Results indicated that the hepatic GSH/GSSG ratio was maintained after an occlusion of the SMV, despite a decrease in adenosine triphosphate (ATP) level and energy charge potential. However, plasma levels of total glutathione and GSSG in the inferior vena cava increased after SMV occlusion and continued to increase after reperfusion. Biliary GSSG efflux decreased during 30-min occlusion of the SMV, and remained low even after reperfusion. The liver maintains homeostasis despite a decrease in biliary GSSG efflux, probably by secreting excess GSSG into the hepatic vein when the SMV is occluded. We conclude that the total amount of glutathione and GSSG in the plasma is directly correlated with oxidative stress in the liver.

Recurrent splenic artery aneurysms developing after aneurysmectomy without splenectomy: report of a case

We report herein the case of a 47-year-old man who developed a huge splenic artery aneurysm (SAA) with splenomegaly, for which ligation of the splenic artery and partial aneurysmectomy was performed. A celiac arteriogram taken 2 months postoperatively revealed that two small aneurysms had developed in the collateral vessels, indicating that increased blood flow through the collateral circulation could be responsible for the formation of secondary aneurysms. This postoperative change suggests that the etiology is related to the SAA and thus, the possibility that aneurysms may develop in the collateral vessels following spleen-preserving procedures for SAA must be borne in mind and careful follow-up performed at regular intervals.

Complete obstruction of the inferior vena cava due to chronic relapsing pancreatitis: a case report

A woman aged 62 with long history of chronic relapsing pancreatitis presented with swelling and ulcer in the lower limbs and occasional gastrointestinal bleeding. The radiological imaging showed complete obstruction of Inferior Vena Cava (IVC) at the level of the pancreas and well developed collateral vessels. Portal vein and splenic vein were also obstructed and superior mesenteric venous blood drained into the liver via coronary vein. She was originally found to have pancreas head tumor, which was not resectable. A palliative operation was performed, but histological examination of pancreatic specimen suggested only chronic inflammation and no evidence of malignancy. She was diagnosed as tumor-forming type chronic pancreatitis. Although SPV or SMV-PV obstruction has been recognized as a complication of chronic pancreatitis, IVC obstruction can occur by the same mechanism. This is the only case but one ever reported. Not only splenoportography but IVC-graphy will contribute to more precise understanding of patient's condition with chronic pancreatitis.

Space experiment using large-sized fish: in case of carp in Spacelab-J mission

Two carp of 26 cm in size, intact and otolith-removed (LB), were flown on the Spacelab-J for 8 days in September 12-20, 1992. Light-dependent reaction to alternating direction of illumination was recorded for 10 min twice a day together with the cerebellar EEG activity, on 2 days before the launch, during the flight and for 4 days after the landing, in same fish chamber. Reproducing the video image, it was revealed that both carp were healthy during the mission, but the LB fish was almost immobilized from the 3rd test session (48 hours in flight) by tight twisting of the EEG cable. Both fish after landing tended to stay still on the bottom of the fish chamber. Findings that the body weight reduced remarkably in both fish and that nitrite and nitrate levels of the fish water were usually high, suggested that the fish metabolism might have been enhanced during the flight.

Isolation of a human biliary glycoprotein inhibitor of cholesterol crystallization

BACKGROUND

About 50% of populations in developed countries have bile supersaturated with cholesterol, which is a major risk factor for cholesterol gallstone formation. Despite the prevalence of supersaturated bile, only about 10% of these populations develop gallstones. The existence of a biliary protein that inhibits cholesterol crystallization was hypothesized to explain this discrepancy. This report outlines the purification and characterization of such a human biliary glycoprotein.

METHODS

Chromatographic methods were used for separation and characterization. Additional steps included activity analysis by crystal growth assay, electrophoresis, and deglycosylation.

RESULTS

The glycoprotein consists of a heterodimer, M(r) of 120 kilodalton, with subunits of M(r) of 63 kilodalton and 58 kilodalton. Each of the subunits is characterized by an isoelectric point of 6.6 and shows comparable inhibitory activity. Deglycosylation of the subunits show that they share a similar polypeptide backbone (M(r) of 35 kilodalton) based upon a highly similar amino acid profile. This suggests that differential subunit glycosylation alone may account for the apparent heterodimeric structure.

CONCLUSIONS

No other human biliary glycoprotein has been found thus far that shows cholesterol crystal growth-inhibiting activity. Thus, it may be of importance in preventing gallstone formation in healthy populations.

Postural control of fish related to gravity input

The disappearance of gravity input during space flight causes many functional disorders in animal and human postural control system. On the other hand, it has been shown that these functional deficits reduce or disappear with time and adapt to weightlessness. Unusual fish behavior was reported during the first few days of orbit flight and also during postflight recovery in Skylab 3 experiment. Similar fish behavior was observed in microgravity obtained during the parabolic flight of airplane. These results suggest that fish might provide a good model for investigating adaptation of sensory-motor interaction in microgravity. The fish generally show a "dorsal light response (DLR)" indicating how these postural mechanisms concern with the environment. That is, when a light is presented laterally, a fish rolls its dorsal surface toward the light an equilibrium point between the gravity vector and the light source vector. In addition, the DLR after bilaterally labyrinthectomy or changes of the DLR in microgravity show the involvement of other factors related to the changes of gravity. In this investigation, the behavioral changes of bilaterally labyrinthectomized (BL) and unilaterally labyrinthectomized (UL) fish adapted for more than 3 months on the ground postoperatively were used to analyze whether buoyancy was affected by injecting of a contrast medium into the swimming bladder.