Cavin-1 modulates BMP/Smad signaling through the interaction of Caveolin-1 with BMPRII in pulmonary artery endothelial cells

Background

Pulmonary hypertension (PH) is a progressive disease associated with poor outcomes. Caveolin-1 (Cav1) and Cavin-1 are components of caveolae, and Cav1 is identified as a related gene of pulmonary arterial hypertension (PAH). Gene mutations of bone morphogenetic protein type II receptor (BMPRII) is the most common cause of PAH. BMPRII is localized in caveolae and associates with Cav1. However, the role of the Caveolin-Cavin system on the BMP/Smad signaling and the PAH progression has not been well-known.

Purpose

Our study aims to investigate the relationship between Caveolin-Cavin system and BMP/Smad signaling pathway in pulmonary artery endothelial cells (PAECs). [Methods] Cav1 knockout mice were used to assess PH, and caveolae in PAECs were observed by electron microscope. After knocking down Cav1 and/or Cavin-1 in human PAECs (hPAECs) using siRNA, we evaluated the phosphorylation of Smad by Western blotting. Apoptosis was explored by flow cytometry. To assess the interaction between Cav1 and BMPRII, and the effect of Cavin-1 for this interaction and BMP/Smad signaling, we performed immunoprecipitation, Co-immunostaining, Proximal Ligation Assay (PLA), GST pulldown assay, and Western blotting.

Results

As in previous reports, Cav1 knockout mice exhibited PH with pulmonary vascular remodeling and right ventricular hypertrophy and PAECs isolated from Cav1 knockout mice showed caveolae disappearance. Cav1 knockdown in hPAECs reduced BMPRII at the plasma membrane and Smad 1/5/9 phosphorylation. Cav1 knockdown also significantly increased hypoxia-induced apoptosis in hPAECs. Co-immunostaining revealed that Cav1 was associated with BMPRII at the membrane of hPAECs. Cavin-1 inhibited the interaction of BMPRII with Cav1 and reduced BMPRII localization on the membrane of hPAECs. GST pulldown assay revealed that Cavin-1 and BMPRII were associated with Cav1 through the scaffolding domain in Cav1. These findings suggest that Cavin-1 and BMPRII are competitively associated with Cav1. Cavin-1 knockdown improved the interaction between Cav1 and BMPRII and inhibited both BMPRII reduction at the plasma membrane and Smad 1/5/9 dephosphorylation.

Conclusions

Cavin-1 affects the interaction of Cav1 with BMPRII at the plasma membrane and modulates BMP/Smad signaling in PAECs. The binding of Cavin-1 to Cav1 enhances the interaction between BMPR2 and Cav1, resulting in stabilization of BMPRII localization at the plasma membrane in PAECs and prevention of BMP/Smad signaling attenuation, which is important for PAH development.

Funding Acknowledgement

Type of funding sources: None.

Relationship between the length of the forefoot bones and performance in male sprinters

Although recent studies have reported that the forefoot bones are longer in sprinters than in non-sprinters, these reports included a relatively small number of subjects. Moreover, while computer simulation suggested that longer forefoot bones may contribute to higher sprint performance by enhancing plantar flexor moment during sprinting, the correlation between forefoot bone length and sprint performance in humans has not been confirmed in observational studies. Thus, using a relatively large sample, we compared the length of the forefoot bones between sprinters and non-sprinters. We also examined the relationship between forefoot bone length and performance in sprinters. The length of forefoot bones of the big and second toes in 36 well-trained male sprinters and 36 male non-sprinters was measured using magnetic resonance imaging. The length of forefoot bones in the big and second toes was significantly longer in sprinters than in non-sprinters. After dividing the sprinters into faster and slower groups according to their personal best time in the 100-m sprint, it was found that the forefoot bone length of the second toe, but not that of the big toe, was significantly longer in faster group than in slower group. Furthermore, the forefoot bone length of the second toe correlated significantly with the personal best time in the 100-m sprint. This study supported evidence that the forefoot bones are longer in sprinters than in non-sprinters. In addition, this is the first study to show that longer forefoot bones may be advantageous for achieving superior sprint performance in humans.

Ischemic Preconditioning Enhances Muscle Endurance during Sustained Isometric Exercise

Ischemic preconditioning (IPC) enhances whole-body exercise endurance. However, it is poorly understood whether the beneficial effects originate from systemic (e. g., cardiovascular system) or peripheral (e. g., skeletal muscle) adaptations. The present study examined the effects of IPC on local muscle endurance during fatiguing isometric exercise. 12 male subjects performed sustained isometric unilateral knee-extension exercise at 20% of maximal voluntary contraction until failure. Prior to the exercise, subjects completed IPC or control (CON) treatments. During exercise trial, electromyography activity and near-infrared spectroscopy-derived deoxygenation in skeletal muscle were continuously recorded. Endurance time to task failure was significantly longer in IPC than in CON (mean±SE; 233±9 vs. 198±9 s, P<0.001). Quadriceps electromyography activity was not significantly different between IPC and CON. In contrast, deoxygenation dynamics in the quadriceps vastus lateralis muscle was significantly faster in IPC than in CON (27.1±3.4 vs. 35.0±3.6 s, P<0.01). The present study found that IPC can enhance muscular endurance during fatiguing isometric exercise. Moreover, IPC accelerated muscle deoxygenation dynamics during the exercise. Therefore, we suggest that the origin of beneficial effects of IPC on exercise performance may be the enhanced mitochondrial metabolism in skeletal muscle.

Topochemical conversion of a dense metal-organic framework from a crystalline insulator to an amorphous semiconductor

A dense, insulating metal–organic framework (MOF), is successfully converted into a semiconducting amorphous MOF via a topochemical route.

The topochemical conversion of a dense, insulating metal–organic framework (MOF) into a semiconducting amorphous MOF is described. Treatment of single crystals of copper(i) chloride trithiocyanurate, Cu^ICl(ttcH₃) (ttcH₃ = trithiocyanuric acid), 1, in aqueous ammonia solution yields monoliths of amorphous Cu^I_1.8(ttc)_0.6(ttcH₃)_0.4, 3. The treatment changes the transparent orange crystals of 1 into shiny black monoliths of 3 with retention of morphology, and moreover increases the electrical conductivity from insulating to semiconducting (conductivity of 3 ranges from 4.2 × 10^–11 S cm^–1 at 20 °C to 7.6 × 10^–9 S cm^–1 at 140 °C; activation energy = 0.59 eV; optical band gap = 0.6 eV). The structure and properties of the amorphous conductor are fully characterized by AC impedance spectroscopy, X-ray photoelectron spectroscopy, X-ray pair distribution function analysis, infrared spectroscopy, diffuse reflectance spectroscopy, electron spin resonance spectroscopy, elemental analysis, thermogravimetric analysis, and theoretical calculations.

Visualization of Flow Instabilities for High Density Polyethylene

Two typical flow instabilities of “Shark Skin” and “Melt Fracture” for high density polyethylene were investigated in this report. Experimental measurements were carried out methodically in a wide flow region from the reservoir (entry region) to the die land with a specific slit die. Especially the flow pattern was visualized with a high speed camera and the frequency of the flow instability was analyzed. Corresponding to the visualization analysis, the pressure fluctuation in the slit die and the surface roughness at the die exit were measured simultaneously and these frequency characteristics were analyzed with a FFT (Fast Fourier Transform) analyzer. As for “Shark Skin” region, the irregularity of the surface roughness in the broad frequency band was recognized at the die exit. In spite of this surface roughness, the pressure fluctuation and the fluctuation of the flow pattern at the wall vicinity in the die land were not observed. These results indicate that “Shark Skin” occurs at the die exit. As for “Melt Fracture” region, the periodical oscillation of the flow pattern and the periodical pressure fluctuation which corresponded to the periodical distortion of the extrudate was recognized in the die land. However the periodical oscillation of the flow pattern and the periodical pressure fluctuation could not be recognized in the reservoir (entry region of the die land). These results indicate that “Melt Fracture” is initiated at the die entry and occurs in the die land. Consequently it is clarified that “Shark Skin” occurs at the die exit and the flow instability which lead to “Melt Fracture” is initiated at the die entry and occurs in the die land.

Quantitative Analysis for Polymer Degradation in the Extrusion Process

Polymer degradation in the extrusion process decreases quality and productivity. For this reason, it is necessary to prevent polymer degradation. In the extrusion process, polymer degradation is caused by oxidation. It depends on the processing temperature and the amount of dissolved oxygen in the molten polymer. Therefore, a quantitative analysis of these factors is required.

As for the degradation characteristics of the material used in this study, temperature and oxygen concentration dependency of the oxidation rate could be quantitatively characterized with an apparatus to evaluate polymer degradation which utilized chemiluminescence generated by an oxidation reaction.

Moreover, an online measuring apparatus to analyze dissolved gas in the extruded molten polymer was developed. With this apparatus, the volume ratio of dissolved gases (N2, O2 etc.) to the extruded molten polymer could be quantitatively analyzed and the quality of the extruded molten polymer evaluated.

With this apparatus, dissolved nitrogen (an index of entrained air) was analyzed with a full-flight screw and a barrier screw. Furthermore, observation of cross sectional views in the screw channel obtained from the cooling experiment under the operating conditions was carried out for the full-flight screw and the barrier screw. With the full-flight screw, break up phenomenon (collapse of solid polymer) occurred in the screw channel and the amount of nitrogen increased. With the barrier screw, the amount of nitrogen decreased because of prevention of the break up phenomenon in the screw channel.

Consequently, it is shown that the use of the barrier screw is suitable for oxygen reduction in the molten polymer, which is a factor in causing polymer degradation.

[Provision for adverse effect of S-1 containing chemotherapy in patients with advanced digestive cancer--combination with superfine dispersed lentinan]

PURPOSE

Recently, in drug therapy for patients with advanced digestive cancer, S-1 (tegafur x gimeracil x oteracil potassium) alone or S-1 combined with other chemotherapeutic agents (S-1+alpha) is prescribed. However, many patients are often forced to give up long-term S-1 treatment owing to high incidence rates of adverse effects. The purpose of this study was to evaluate the efficacy of superfine dispersed lentinan (SDL) for the suppression of adverse effects of S-1 or S-1+alpha.

SUBJECTS AND METHOD

The subjects were 72 patients who had unresectable or recurrent advanced digestive cancer. The subject group consisted of 45 men and 27 women, with a median age of 64 (31-85) years; 29 gastric, 25 colorectal, 10 pancreatic and 8 other digestive cancer patients. Thirty -one patients were administered S-1 alone and 41 patients were administered S-1+alpha. SDL (15mg of lentinan/bag/day) was orally administered to all patients for 12 weeks. Adverse events and overall survival time were evaluated according to the CTCAE ver 3.0 and the Kaplan-Meier method, respectively.

RESULTS

Seventy-two patients were enrolled in this study. Adverse events which had an undeniable causal relationship to SDL were observed in 2 patients (2.7 %, constipation [Grade 2] and nausea [Grade 1]) out of 72 patients; all of the events were not severe and disappeared when the SDL administration was discontinued. Adverse events associated with S-1 or S-1+ alpha were observed in 9 patients (12.5% ) (11 events) out of 72 patients. Grade 3 adverse events were observed in 3 patients (4.2% ) (leukopenia, 2; thrombocytopenia, 1). Incidence rates of both hematological and nonhematological adverse events were very low. In no gastrointestinal toxicity associated with S-1 or S-1+alpha was observed, which was estimated to be an effect of SDL combination. Mean survival times in gastric cancer and colorectal cancer patients were 9. 5 months (95%confidential interval [CI], 7.0-22.4 months) and 18.4 months (95% CI, 13.2 -28.5 months), respectively.

CONCLUSIONS

From the results of the present study, SDL is considered completely free of anything harmful to advanced digestive cancer patients and is effective for the suppression of adverse effects of S-1 or S-1+alpha therapy. It is suggested that SDL can prolong the administration period of S-1 and, as a result, contribute to prolongation of survival in patients with advanced digestive cancer.

Improvement of QOL and prognosis by treatment of superfine dispersed lentinan in patients with advanced gastric cancer

BACKGROUND/AIMS

Intravenous lentinan administration has life prolongation effect for gastric cancer patients when combined with chemotherapy. Recently, superfine dispersed lentinan--an oral formulation--has become clinically available. In order to evaluate the efficacy of superfine dispersed lentinan, was conducted multicenter clinical study.

METHODOLOGY

Twenty-seven patients with unresectable or recurrent gastric cancer were enrolled and answered the quality of life questionnaire before and 4, 8, and 12 weeks after the initiation of superfine dispersed lentinan administration. Survival times were evaluated according to results of 3-year follow-up survey.

RESULTS

There was no adverse event with causal relation to superfine dispersed lentinan. Median survival time was 17.1 months (95% confidence interval: 6.9-25.9 months) in 26 eligible patients. Six (23%) out of 26 patients were alive longer than 3 years. There was a significant correlation between the quality of life scores at 12 weeks of superfine dispersed lentinan treatment and survival times.

CONCLUSIONS

Superfine dispersed lentinan is deemed free of anything harmful. Quality of life status at 12 weeks of superfine dispersed lentinan treatment appears to be a promising prognostic predictor.

Efficacy of orally administered superfine dispersed lentinan (beta-1,3-glucan) for the treatment of advanced colorectal cancer

BACKGROUND

Lentinan (LNT) is an immune adjuvant medicine for advanced gastric cancer in Japan. Recently, an oral formulation of superfine dispersed lentinan (SDL) has become clinically available. To investigate the safety and effectiveness of SDL, a multi center clinical study in patients with advanced colorectal cancer was conducted.

PATIENTS AND METHODS

Adverse events were assessed and the patients' quality of life (QOL) and the binding ability of peripheral blood monocytes (PBM) to LNT were also evaluated.

RESULTS

Four grade 2 adverse events associated with SDL treatment were observed among the 80 patients. Adverse events associated with chemotherapy were observed in 9 out of the 64 chemotherapy-treated patients. Among the 48 patients assessed for QOL, the patients with low QOL scores before SDL treatment (n=23) reported a significant improvement in their QOL scores after 12 weeks of SDL administration. The rates of LNT-binding PBM in the QOL-improved group were significantly higher than those in the QOL-not-improved group (p<0.05).

CONCLUSION

SDL was safe and effective for suppressing the adverse effects of chemotherapy as well as improving QOL. The binding ability of PBM to LNT appears to be a promising predictor of QOL improvement after SDL administration.

Clinical efficacy of superfine dispersed lentinan (beta-1,3-glucan) in patients with hepatocellular carcinoma

BACKGROUND/AIMS

Recently, complementary alternative medicine is actively performed for cancer therapy. We investigated the effectiveness of supplementary food containing superfine dispersed lentinan (beta-1,3-glucan) in patients with unresectable or recurrent hepatocellular carcinoma in a multi-center study.

METHODOLOGY

Peripheral blood was collected prior to the test food ingestion and was incubated with fluorescein-labeled lentinan. The rates of lentinan-binding CD14+ monocytes were determined by flow cytometry. Patient survival times were followed up for 3 years.

RESULTS

Thirty-six patients were eligible among 40 enrolled patients. Median survival time of eligible patients was 13.6 months (95% confidence interval, 8.7-18.9 months). Survival times of patients who ingested test food for a mean period of 47 weeks (range, 26 to 145 weeks) were significantly longer than that of patients who ingested for 7 to 12 weeks (p < 0.05). The rates of lentinan-binding cells in CD14+ monocytes showed individual variations (0.1-19.7%; Median, 1.6%). Survival times (median survival time, 16.3 months) of lentinan-high-binding group were significantly longer than those (median survival time, 12.5 months) of lentinan-low-binding group (p < 0.05).

CONCLUSIONS

A superfine dispersed lentinan-containing supplementary food is effective for hepatocellular carcinoma patients' survival. Long-time ingestion is preferable. Assessment of lentinan-binding CD14+ monocytes is a promising prognostic predictor.

Efficacy of oral administered superfine dispersed lentinan for advanced pancreatic cancer

BACKGROUND/AIMS

Recently, complementary alternative medicine is actively performed for cancer therapy. Superfine dispersed lentinan (beta-1,3-glucan)--an oral effective form--was recently developed and available. We investigated the effectiveness of superfine dispersed lentinan in advanced pancreatic cancer patients in a multi-center study.

METHODOLOGY

Twenty-nine patients with unresectable and recurrent pancreatic cancer were enrolled, and adverse events and quality of life scores were assessed. Survival times were evaluated according to results of a 3-year follow-up survey.

RESULTS

Although a diarrhea of grade-1 adverse event dependent on the test article (3.4%) was observed, the symptom was remitted without any treatment. This indicates that test article was free of anything harmful. Median survival time was 12.1 months (95% confidence interval: 7.3-25.7 months) in 25 eligible patients. Five (20%) out of 25 patients were alive for 3 years. There was a significant correlation between the quality of life scores after the superfine dispersed lentinan treatment and survival times.

CONCLUSIONS

A superfine dispersed lentinan is deemed safe and effective for advanced pancreatic patients' survival and improvement of quality of life. And the assessment of quality of life status after the administration of superfine dispersed lentinan is a promising prognostic predictor.

Intratesticular localization of the organic solute carrier protein, OSCP1, in spermatogenic cells in mice

Organic solute carrier protein 1 (OSCP1) is a recently described human gene that facilitates the transport of various organic solutes into the cell, when expressed in frog eggs. In this study, we cloned a mouse ortholog of OSCP1 encoding 379 amino acid protein, with 94% homology to the human counterpart. The mouse OSCP1 mRNA was predominantly expressed in the testis, in which it was attributed to the spermatogenic cells, except the spermatogonia. Immunohistochemistry confirmed that OSCP1 protein is continuously expressed during spermatogenesis in a stage- and cell type-specific manner, in the leptotene spermatocytes at stage IX through step 15 spermatids. Subcellular fractionation of mouse testis homogenates indicated that OSCP1 is a 45-kDa cytosolic protein. Moreover, when green fluorescent protein-OSCP1 fusion constructs were transfected into cultured cells, the fluorescence localized evenly in the cytoplasm. These results suggest that mouse testis OSCP1 may indirectly mediate substrate uptake into meiotic and spermiogenic germ cells, within the cytosol.

Potentiation of intestinal immunity by micellary mushroom extracts

Mushroom (shiitake) extracts were dispersed with lecithin micelles to prepare superfine particles (0.05 to 0.2 microm in diameter) of beta-1,3-glucan (micellary mushroom extracts). When mice were fed with these micelles of beta-glucan (0.75 mg/day/mouse, smaller amounts of beta-glucan), the number of lymphocytes yielded by the small intestine increased by up to 40%. More interestingly, the ratio of CD8alphabeta(+)TCRalphabeta(+) cells/CD8alphaalpha(+)TCRalphabeta(+) cells increased prominently. In parallel with this deviation in the distribution of lymphocyte subsets, tumor cytotoxicity against P815 cells and cytokine productions were also augmented. In other words, phylogenetically developed lymphocytes (CD8alphabeta(+), TCRalphabeta(+)) were much more effectively activated by the oral administration of micellary beta-glucan. These results suggest that smaller amounts of micellary beta-glucan might be useful for the potentiation of intestinal immunity.

Molecular cloning of a structural homolog of YY1AP, a coactivator of the multifunctional transcription factor YY1

YY1 is a multifunctional transcription factor that activates or represses gene transcription depending on interactions with other regulatory proteins that include coactivator YY1AP. Here, we describe the cloning of a novel homolog of YY1AP, referred to as YARP, from the human neuroblastoma cell line SK-N-SH. The cloned cDNA encoded a 2240 amino acid protein that contained a domain which was 97% homologous to an entire YY1AP sequence of 739 amino acids. Two splice variants, YARP2 and YARP3, were also cloned. Northern blotting demonstrated the YARP mRNA (approximately 10 kb), which was increased 1.7-fold after dibutyryl cAMP-induced neural differentiation of the cells. Presence of YARP mRNA was also confirmed in human tissues such as the heart, brain and placenta. Bioinformatic analysis predicted various functional motifs in the YARP structure, including nuclear localization signals and domains associated with protein-protein interactions (PAH2), DNA-binding (SANT), and chromatin assembly (nucleoplasmin-like), outside the YY1AP-homology domain. Thus, we propose that YARP is multifunctional and plays not only a role analogous to YY1AP, but also its own specific roles in DNA-utilizing processes such as transcription.

Cloning and expression analysis of YY1AP-related protein in the rat brain

YY1AP-related protein (YARP) is a structural homolog of YY1AP, a transcriptional coactivator of the multifunctional transcription factor YY1. We cloned a rat YARP cDNA that encoded a 2256 amino acid protein with 93% homology to the human counterpart. Northern blots revealed significant expression of the YARP gene in the rat brain. In situ hybridization demonstrated its expression in neurons throughout the brain, including pyramidal cells in the cerebral cortex and hippocampus and granule cells in the dentate gyrus. YARP was coexpressed with YY1 in these same neuronal cells. However, there was no evidence of YARP expression in glia. In the developing rat brain, the level of YARP mRNA ( approximately 10 kb) peaked at embryonic day 18 and promptly declined thereafter to reach the steady-state level found in adulthood, by 14 days after birth. These results suggest that YARP functions at a late stage of neurogenesis during perinatal development of the rat brain, as well as in mature neurons.

Phase II study of the efficacy of gefitinib in patients with non-small cell lung cancer with the EGFR mutations

7183

Purpose: Recent studies have indicated that the mutations of epidermal growth factor receptor (EGFR) were associated with sensitivity of non-small cell lung cancer (NSCLC) to gefitinib, an EGFR tyrosine kinase inhibitor. The clinical objective of this study was to prospectively evaluate the efficacy of gefitinib in patients with stageIII/IV NSCLC that had the EGFR mutations. Methods: Genomic DNA was extracted from tumor specimens and EGFR mutations in exon 19 and 21 were analyzed by direct sequencing. Patients with stageIII/IV NSCLC who had the EGFR mutations were treated with gefitinib (250mg) orally. Response, survival data and toxicity were assessed. Results: From Nov. 2004 to Dec 2005, 14 patients with the EGFR mutations received gefitinib (median age: 67 years; 2 males, 12 females; 1 smokers, 13 non-smokers; all adenocarcinomas). Two patients discontinued gefitinib and came off study because of interstitial pneumonitis (grade 3) and acne (grade 3), respectively. Response data are available for 12 patients. Two achieved a complete response (CR), seven exhibited a partial response (PR) and three had stable disease (SD). Response rate and disease control rate were 75% and 100%, respectively. There were no grade 3/4 toxicities in these 12 patients. All patients were alive during median follow-up period of 8 months (range 1–13 months). Conclusions: The EGFR mutations could be an excellent predictor of response to gefitinib in NSCLC.

No significant financial relationships to disclose.

Sterol Regulatory Element-Binding Protein-2 modulates human brain acyl-CoA hydrolase gene transcription

The brain shows high catalyzing activity during hydrolysis of long-chain acyl-CoAs into fatty acids and CoA-SH. Brain acyl-CoA hydrolase (BACH) is responsible for most of the long-chain acyl-CoA hydrolyzing activity in the brain and is localized exclusively in neurons. We analyzed the human BACH gene promoter, focusing on transcriptional regulation by Sterol Regulatory Element-Binding Protein-2 (SREBP-2), which is a transcription factor that activates genes involved in cholesterol biosynthesis and uptake. When the nuclear form of SREBP-2 gene was transfected into human neuroblastoma cells, transcription of a BACH gene promoter-luciferase reporter gene was activated through a sterol regulatory element (SRE) motif. Moreover, a gel shift assay demonstrated that SREBP-2 specifically bound to the SRE motif. These results suggest that transcription of the BACH gene is activated by SREBP-2. This study also provides insights into BACH function in the interaction between the metabolism of acyl-CoAs and cholesterol in neurons.

Localization of a long-chain acyl-CoA hydrolase in spermatogenic cells in mice

Brain acyl-CoA hydrolase (BACH) hydrolyzes long-chain acyl-CoAs to free fatty acids and CoA-SH. BACH is highly distributed in brain and is localized in neurons, but not glial cells. This suggests that BACH plays a specific role in neurons. BACH is also detected in testis, although the expression profile of BACH is unknown in testis. In this study, developmental changes and cellular distribution of BACH were examined in mouse testis. Before postnatal day (P) 10, BACH was detected at very low levels by Western blotting. Then, BACH content rapidly increased from P14 and reached maximum levels at P21, remaining high until at least P70. The increase in BACH content corresponded to the appearance of pachytene spermatocytes, which was confirmed by immunohistochemistry. BACH was also detectable in spermatids, but not in spermatogonia, mature spermatozoa. These results suggest that BACH is expressed in a cell-specific manner and plays a role in spermatogenesis.

Tumour matrilysin expression predicts metastatic potential of stage I (pT1) colon and rectal cancers

BACKGROUND AND AIMS

Nodal metastases are indisputable determinants of prognosis for colon and rectal cancer. Using classical histological criteria, many attempts to predict nodal metastasis have failed, preventing the adequate management of stage I (pT1) cancer. We investigated the role of tumour matrilysin in predicting metastatic potential, and discuss its potential use in individualising treatment of pT1 colon and rectal cancer.

METHODS

The gene signature associated with nodal metastasis was investigated by cDNA array in 24 colon and rectal cancers. We studied 494 colon and rectal cancer patients to identify risk factors for nodal metastasis and evaluated the potential to predict nodal metastasis by either the logistic regression model or the Bayesian neural network model with built-in matrilysin. We then inferred possible causality of nodal metastasis from structural equation modelling.

RESULTS

cDNA array revealed that matrilysin was maximally upregulated in the metastasis signature identified. Tumour matrilysin expression emerged as a stage independent risk factor for nodal metastasis, resulting in a similar predictive performance in receiver operating characteristic curve analysis in the two models. A Bayesian approach called automatic relevance determination identified matrilysin as one of the most relevant predictors examined. Structural equation modelling suggested possible direct causality between matrilysin and nodal metastasis.

CONCLUSIONS

We have provided evidence that tumour matrilysin expression is a promising biomarker predicting nodal metastasis of colon and rectal cancer. Analysis of tumour matrilysin expression would help clinicians achieve the goal of individualised cancer treatment based on the metastatic potential of pT1 colon and rectal cancer.

Actinobacillus actinomycetemcomitans Y4 capsular polysaccharide induces IL-1beta mRNA expression through the JNK pathway in differentiated THP-1 cells

Capsular polysaccharide from Actinobacillus actinomycetemcomitans Y4 (Y4 CP) induces bone resorption in a mouse organ culture system and osteoclast formation in mouse bone marrow cultures, as reported in previous studies. We also found that Y4 CP inhibits the release of interleukin (IL)-6 and IL-8 from human gingival fibroblast (HGF). Thus Y4 CP induces various responses in localized tissue and leads to the secretion of several cytokines. However, the effects of Y4 CP on human monocytes/macrophages are still unclear. In this study, THP-1 cells, which are a human monocytic cell line, were stimulated with Y4 CP, and we measured gene expression in inflammatory cytokine and signal transduction pathways. IL-1beta and tumour necrosis factor (TNF)-alpha mRNA were induced from Y4 CP-treated THP-1 cells. IL-1beta mRNA expression was increased according to the dose of Y4 CP, and in a time-dependent manner. IL-1beta mRNA expression induced by Y4 CP (100 microg/ml) was approximately 7- to 10-fold greater than that in the control by real-time PCR analysis. Furthermore, neither PD98059, a specific inhibitor of extracellular signal-regulated kinase nor SB203580, a specific inhibitor of p38 kinase prevented the IL-1beta expression induced by Y4 CP. However, JNK Inhibitor II, a specific inhibitor of c-Jun N-terminal kinase (JNK) prevented the IL-1beta mRNA expression induced by Y4 CP in a concentration-dependent manner. These results indicate that Y4 CP-mediated JNK pathways play an important role in the regulation of IL-1beta mRNA. Therefore, Y4 CP-transduced signals for IL-1beta induction in the antibacterial action of macrophages may provide a therapeutic strategy for periodontitis.

Detection of tryptase-, chymase+ cells in human CD34+ bone marrow progenitors

BACKGROUND

Mast cells (MCs) arise from haematopoietic stem cells. We have recently reported that CD34(+) progenitors derived from human bone marrow (BM) develop into tryptase+, chymase+ MCs when cultured in the presence of recombinant human stem cell factor (rhSCF) and recombinant human IL-6 (rhIL-6). In an experiment for the expression of chymase during differentiation, chymase+ cells were detected in human BM, but tryptase+ cells were not found.

OBJECTIVE

The purpose of this study was to show the appearance of chymase+ cells in CD34(+) cells with an origin different from MC differentiation.

METHODS

CD34(+) cells from human BM were sorted with anti-CD117 monoclonal antibody (mAb), and cytospins of CD34(+), CD34(+)CD117(+), or CD34(+)CD117(-) were prepared. These cells were cultured with rhSCF+rhIL-6 for 12 weeks. Some of the cells were subjected to either histological stain with Wright-Giemsa or immunocytochemistry with anti-chymase mAb. Real-time RT-PCR was also performed to compare the transcriptional level of chymase from each cell preparation.

RESULTS

Chymase was expressed in CD34(+) cells as well as human MCs by immunocytochemistry. Substantial CD34(+)CD117(-) cells, but not CD34(+)CD117(+) cells, were stained immunocytochemically with anti-chymase mAb. For 1 week culture with rhSCF+rhIL-6, no cells expressed chymase in any preparation. Real-time RT-PCR revealed positivity for chymase mRNA in CD34(+) cells, but it reduced at 1 week of culture, and increased as cells developed into MCs. Chymase mRNA in CD34(+)CD117(+) cells was negligible compared with that in CD34(+)CD117(-). Tryptase mRNA was below the detectable level in CD34(+) cells, and increased along with MC differentiation. After 12 weeks of culture, CD34(+)CD117(+) developed predominantly into MCs, whereas CD34(+)CD117(-) developed into monocytes/macrophages.

CONCLUSION

Our findings suggested that chymase is present not only in MCs but also in CD34(+)CD117(-) BM progenitors, but that its origin is different from the MC lineage.

A 50-kDa isoform of mouse brain acyl-CoA hydrolase: expression and molecular properties

Brain acyl-CoA hydrolase (BACH) is responsible for most of the long-chain acyl-CoA hydrolyzing activity in the brain and is localized exclusively in neurons. There are two BACH isoforms: the major isoform, a 43-kDa BACH, and a lesser isoform, a 50-kDa BACH. In our previous work [Brain Res. Mol. Brain Res. 98 (2002) 81], a possibility was raised that these BACH isoforms might be generated from a single mRNA species via a mechanism of alternative use of translation start sites. However, the results obtained in the current study indicated that the 43-kDa BACH and 50-kDa BACH are not generated from a single mRNA species, but from distinct mRNA species transcribed by alternative use of transcription start sites. The molecular properties of the 50-kDa BACH were compared to those of the 43-kDa BACH. Palmitoyl-CoA hydrolase activity and protein stability were almost the same between both BACH isoforms. In addition, both 43-kDa BACH and 50-kDa BACH that were fused to green fluorescent protein showed cytosolic distribution. These results suggest that the 50-kDa BACH plays a similar role as the 43-kDa BACH. Therefore, since the 43-kDa BACH is expressed at higher levels than 50-kDa BACH, the 43-kDa BACH should largely contribute to understanding the physiological functions of the BACH gene in neurons.

High glucose augments arginase activity and nitric oxide production in the renal cortex

To clarify the interaction between arginase and nitric oxide (NO) production in the kidney with normal and high glucose levels, renal cortical slices from male Sprague-Dawley rats were incubated in Hank's solution containing various concentrations of L-norvaline (Nval; an arginase inhibitor), 500 U/mL superoxide dismutase, and either 5 mmol/L (normal) or 20 mmol/L (high) glucose (n = 5 per group). Incubation with Nval increased renal cortical NOX (nitrite + nitrate) production dose-dependently, indicating competition between arginase and NO synthase (NOS) for the substrate (L-arginine). In the basal condition without Nval, high glucose also increased NO(X) production to a rate 3 times that observed during incubation with normal glucose (P < .01). This effect of high glucose was not altered by Nval. Rather, the effects of high glucose and Nval were additive, indicating that the activity of NOS per se is enhanced by high glucose. Direct assay of arginase and NOS activities confirmed stimulation of both enzymes under the high glucose condition (P < .05, P < .01, v normal glucose, respectively). However, high glucose did not change the amount of L-arginine present in renal cortical slices. These data reveal that arginase competes with NOS for L-arginine in the renal cortex, and that high glucose increases the activity of both enzymes without affecting the amount of substrate. These results suggest that increased NOS activity, rather than altered substrate availability, may be the principal factor underlying increased NO synthesis in diabetic kidneys.

Review of combination of peritoneal dialysis and hemodialysis as a modality of treatment for end-stage renal disease

Because the contribution of residual renal function (RRF) to total solute clearance is often significant in continuous ambulatory peritoneal dialysis (CAPD), loss of RRF over time can lead to inadequate dialysis if appropriate prescription management strategies are not pursued. Additionally, declines in ultrafiltration caused by increases in peritoneal permeability may limit continuation of CAPD therapy. Peritoneal dialysis and hemodialysis (PD + HD) combination therapy (complementary dialysis therapy) is an alternative method. This therapy allows the patient to maintain daily activities, as with CAPD, while undergoing once-a-week HD supplements for the insufficient removal of solutes and water. This therapy allows for the continuation of PD without shifting to total HD in PD patients who continue to have uremic symptoms even after individualization of the PD prescription. This treatment option is psychologically more acceptable to patients and may be expected to provide such accompanying beneficial effects as peritoneal resting, improvement of QOL and reduction in medical cost.

Inducible expression of long-chain acyl-CoA hydrolase gene in cell cultures

A long-chain acyl-CoA hydrolase, BACH, is markedly distributed in the brain and localized in neurons. However, the physiological significance of BACH is unclear. To study the gene function, we expressed the mouse BACH gene in C3H 10T1/2 fibroblastic cells using a mifepristone (RU486)-inducible gene expression system. A cell clone, 10T-S6/44, was generated by stable transfection of two plasmids encoding a mifepristone-dependent transactivator and an inducible transgene product, BACH with a C-terminal MYC-tag (BACH-MYC). The transgene expression in the 10T-S6/44 cells was tightly regulated by mifepristone. Induction of BACH-MYC and an increase in palmitoyl-CoA hydrolase activity were observed in the cells treated with 3 x 10(-11) M mifepristone and reached maximal levels at a concentration of 1 x 10(-9) M for 48 h. The growth rate of cells showing the maximal induction of BACH-MYC was reduced, whereas phospholipid synthesis was unchanged. These results suggested that BACH affects specific cellular systems and functions, but not all acyl-CoA-utilizing processes.

Functional expression of high-affinity receptor for immunoglobulin E on mast cells precedes that of tryptase during differentiation from human bone marrow-derived CD34 progenitors cultured in the presence of stem cell factor and interleukin-6

BACKGROUND

CD34(+) progenitor cells develop into tryptase(+), CD117(+) mast cells when cultured in the presence of recombinant human stem cell factor (rhSCF). However, spontaneous IgE receptor (FcepsilonRI) expression during human mast cell development is not well examined.

OBJECTIVE

Here, the expression and function of FcepsilonRI in and on human bone marrow-derived mast cells (HBMMCs) during development were investigated.

METHODS AND RESULTS

At 4 weeks of culture, predominant cells expressed high-affinity IgE receptor alpha chain (FcepsilonRIalpha) on the cell surface determined by flow cytometry, but CD117 was less expressed. Immunocytochemistry with antitryptase mAb and anti-FcepsilonRIalpha mAb revealed intracellular and surface expression of FcepsilonRIalpha at 2 weeks of culture, but tryptase was less expressed. FcepsilonRIalpha mRNA transcript preceded that of tryptase mRNA at 2 weeks of culture determined by real-time RT-PCR, and FcepsilonRIalpha, FcepsilonRIbeta, FcepsilonRIgamma, and tryptase mRNA increased along with differentiation. FcepsilonRIalpha cross-link on HBMMC and 4-week-old mast cells/mast cell precursors induced the release of IL-5 and granulocyte macrophage-colony stimulating factor, which was enhanced by rhSCF.

CONCLUSION

These data indicated that HBMMC constitutively and spontaneously expressed functional FcepsilonRI subunits at the early stage of differentiation, probably because of the differences in the ability and functional property of progenitors.

HEPATOCARCINOGENESIS BY PEROXISOME PROLIFERATORS

It is well known that various kinds of hypolipidemic drugs induce marked changes in the livers of rats and mice. The initial hepatic responses in rodents are marked hepatomegaly, proliferation of peroxisomes in association with changes in peroxisome structure and enzyme composition. Furthermore, since many of hypolipidemic peroxisome proliferators induce hepatocellular carcinomas in both rats and mice, the relationship between peroxisome proliferation and hepatocarcinogenicity of these drugs has become extremely important. However, it has not yet been established whether there are any direct relationships among pharmacological action, peroxisome proliferation and carcinogenicity of these drugs. In order to clarify this task, we have studied the involvement of HGF in hepatocarcinogenesis caused by peroxisome proliferators. After male F-344 rats were orally given Wy-14,643, hepatocarcinomas and (pre) neoplastic nodules were observed in the livers. At that time, the content of HGF and the expression of HGF mRNA were significantly decreased in the liver tumors. These findings may indicate that decreases in hepatic HGF levels are specific events induced by peroxisome proliferators but not by genotoxic carcinogenesis, and that those changes play an important role in the promotion of neoplastic or preneoplastic cell growth induced by peroxisome proliferators. Decrease in HGF induced by peroxisome proliferators such as Wy-14,643 would inhibit the growth of normal hepatocytes and then lend an advantageous circumstance for the selective growth of neoplastic or preneoplastic cells, resulting in the development of growth of tumors.

Expression of acyl-CoA hydrolase in the developing mouse brain

Brain acyl-CoA hydrolase (BACH) is a cytosolic enzyme responsible for the brain long-chain acyl-CoA thioesterase activity, that is the highest in the body. BACH was detected in the mouse brain as early as embryonic day (E) 11.5 by immunoblotting. The level of the major isoform (43-kDa) was low until E12.5, but promptly elevated to a peak 7 days after birth. Thereafter, it declined somewhat and reached a steady-state level in adulthood. These changes in BACH expression were approximately reflected in the palmitoyl-CoA hydrolyzing activity in the developing mouse brain, and the time course was quite similar to that of microtubule-associated protein 2 (MAP2) expression. In immunohistochemistry of E14.5 embryo brains, cells expressing BACH almost coincided with the cells committed to the neuronal lineage, which expressed MAP2 but not nestin. These results indicate that BACH expression is induced during embryogenesis in association with neuronal differentiation, and persists after terminal differentiation into neurons in postnatal stages, resulting in the constitutive high expression of BACH in the adult brain in a neuron-specific manner.

Hepatic induction of mitochondrial and cytosolic acyl-coenzyme a hydrolases/thioesterases in rats under conditions of diabetes and fasting

Acyl-coenzyme A (CoA) hydrolases/thioesterases are a group of enzymes that catalyze the hydrolysis of acyl-CoA thioesters to free fatty acids and CoA-SH. The potency of these enzymes may serve to modulate intracellular concentrations of acyl-CoAs, free fatty acids, and CoA to affect various cellular functions, including lipid metabolism. In this study, we investigated the effect of diabetes and fasting on the protein levels of mitochondrial (MTE-I) and cytosolic acyl-CoA thioesterases (CTE-I), multigene family members of this class of enzymes, in adult rat liver. Rats were treated with alloxan to induce diabetes or fasted for 72 hours. Western blot analysis with the liver homogenates revealed 2.8-fold and 3.8-fold increases in MTE-I and 8.5-fold and 9.2-fold increases in CTE-I under the diabetic and fasting conditions, respectively, compared with the control in which the level of MTE-I was 4.3-fold higher than CTE-I. Serum level of free fatty acids was elevated 5-fold and 2.5-fold in diabetic and fasted rats, respectively. These results confirm the adaptive induction of MTE-I and CTE-I in response to fatty acid overload in the liver, being consistent with their auxiliary role in fatty acid degradation.

Drug Metabolism in Peroxisomes: Involvement of Peroxisomal β-Oxidation System in the Oxidative Chain-shortening of Xenobiotic Acyl Compounds

There are two kinds of beta-oxidation systems of fatty acids in mitochondria and peroxisomes in animal liver cells. These beta-oxidation systems may play different physiological roles in the cell. Peroxisomal beta-oxidation system has been demonstrated to participate in the catabolism of intarcellular acyl compounds such as very long chain fatty acids, long chain dicarboxylic acids and bile acid precursors in addition to fatty acids. The difference of functions between mitochondrial and peroxisomal beta-oxidation systems is mainly due to the difference of characteristics of enzymes participating in the beta-oxidation in both organella. We have studied the beta-oxidation of xenobiotic acyl compounds and found that the peroxisomal beta-oxidation is involved in the chain-shortening of acyl side chains of several compounds. In the present review, the author describes the comparison between peroxisomal and mitochondrial beta-oxidation of phenylfatty acids (PFAs), oxidative chain shortening of N-(alpha-methylbenzyl)azelaamic acid (C(9)) as a specific substrate for the peroxisomal beta-oxidation system, application of C(9) which is a specific substrate for peroxisomal beta-oxidation system for diagnosis of peroxisome disorders and participation of peroxisomal beta-oxidation system in the metabolic activation of prodrugs, YNK-01, by peroxisomal beta-oxidation system.

Human brain acyl-CoA hydrolase isoforms encoded by a single gene

Acyl-CoA hydrolases are a group of enzymes that catalyze the hydrolysis of acyl-CoA thioesters to free fatty acids and CoA-SH. The human brain acyl-CoA hydrolase (BACH) gene comprises 13 exons, generating several isoforms through the alternative use of exons. Four first exons (1a-1d) can be used, and three patterns of splicing occur at exon X located between exons 7 and 8 that contains an internal 3(')-splice acceptor site and creates premature stop codons. When examined with green fluorescent protein-fusion constructs expressed in Neuro-2a cells, the nuclear localization signal encoded by exon 9 was functional by itself, whereas the whole structure was cytosolic, suggesting nuclear translocation of the enzyme. This was consistent with dual staining of the cytosol and nucleus in certain neurons by immunohistochemistry using anti-BACH antibody. The mitochondrial targeting signals encoded by exons 1b and 1c were also functional and directed mitochondrial localization of BACH isoforms with the signals. Although BACH mRNA containing the sequence derived from exon 1a, but not exon X, was exclusively expressed in human brain, these results suggest that the human BACH gene can express long-chain acyl-CoA hydrolase activity in multiple intracellular compartments by generating BACH isoforms with differential localization signals to affect various cellular functions that involve acyl-CoAs.