Effect of over-expression of neuropathy target esterase on mammalian cell proliferation

Neuropathy target esterase (NTE), the human homologue of a protein required for brain development in Drosophila, is expressed primarily in neural cells but is also detected in non-neural cells. Although NTE has been proposed to play a role in neurite outgrowth and process elongation during neurodifferentiation, the function of NTE has not been defined in neural cells. In this study we have investigated the possible role of NTE in neuroblastoma cells and non-neural cells using an over-expression strategy. Over-expression of NTE in human neuroblastoma SH-SY5Y cells and monkey kidney COS7 cells led to an accumulation of NTE on the cytoplasmic surface of the endoplasmic reticulum and inhibition of cell proliferation. In particular, high levels of NTE arrested COS7 cells at G2/M stage yet was not associated with arrest at a particular phase of the cell cycle in SH-SY5Y cells. Moreover, over-expression of NTE did not induce apoptosis in two kinds of cell lines as assessed by flow cytometry. These results suggest that the role of NTE over-expression in cell proliferation is associated with different mechanisms in different cells.

Depot-specific messenger RNA expression of 11β-hydroxysteroid dehydrogenase type 1 and leptin in adipose tissue of children and adults

OBJECTIVE

To compare expression of messenger RNA (mRNA) coding for the cortisol regenerating enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), and the adipocytokines leptin and resistin in paired biopsies of subcutaneous adipose tissue (SC) and omental adipose tissue (OM) from children.

DESIGN

Paired biopsies (SC and OM) were obtained from 54 children (age 0.17-16 years, body mass index (BMI) 12.5-28.3 kg/m(2), BMI standard deviation score (SDS) -2.5-4.5) and 16 adults (age 27-79 years, BMI 19-46 kg/m(2)) undergoing open abdominal surgery. mRNA levels of 11beta-HSD1, leptin and resistin were measured using quantitative real-time polymerase chain reaction (PCR).

RESULTS

11beta-HSD1 mRNA level was higher in OM than in SC (P<0.05), whereas leptin mRNA was higher in SC than in OM (P<0.001). There was no difference in the resistin mRNA level between SC and OM. These results were consistent in children and adults. In children, 11beta-HSD1 mRNA in SC was positively associated with BMI SDS (P<0.05), whereas in OM it was positively associated with age (P<0.05). The association between 11beta-HSD1 expression and age remained significant after adjustment for BMI SDS and gender. Leptin mRNA was positively associated with BMI SDS (SC: P<0.001, OM: P<0.001) but not with age in children. In multiple regression analyses, including anthropometric variables and age, BMI SDS was independently associated with mRNA levels of 11beta-HSD1 (P<0.05) and leptin (P<0.001) in SC. When normal weight and overweight children were analyzed separately, 11beta-HSD1 mRNA levels were positively associated with leptin in OM in the overweight group (P<0.05).

CONCLUSION

There are depot-specific differences in mRNA levels of 11beta-HSD1 and leptin in children and adults. The positive association of 11beta-HSD1 mRNA in OM with age may reflect a causal role in visceral fat accumulation during growth. Increasing 11beta-HSD1 and leptin mRNA in SC with increasing BMI SDS could suggest that the risk of metabolic consequences of obesity may be established early in life.

Reduced semen quality in chronic prostatitis patients that induce the release of apoptotic protein Omi/HtrA2 from spermatozoa

The relationship between chronic prostatitis and fertility has been disputed for many years. Several groups have shown infection and autoimmune response against prostate antigens could have a deleterious effect on semen quality and fertility. This study was conducted to test the hypothesis that Omi/HtrA2-induced apoptosis in chronic prostatitis could be a mechanism underlying the observed clinical benefit. The Omi/HtrA2 serine protease is a nuclear-encoded mitochondrial protein, which can be released from mitochondria into the cytosol after apoptosis stimuli, inducing apoptosis in caspase-dependent and independent manners. Forty-one patients diagnosed as suffering from chronic prostatitis were included. Healthy normal individuals were included as controls. Human spermatozoa in the semen were purified by Percoll-gradient technique to separate the seminal plasma and other round cells. Measurements for sperm concentration, motility, morphology, proinflammatory cytokines, Omi/HtrA2 mRNA and protein levels in spermatozoa of chronic protatitis patients, were performed accordingly. Significantly increased levels of proinflammatory cytokines were detected in seminal plasma from these prostatitis patients. Omi/HtrA2 mRNA and protein levels were significantly higher in prostatitis men than in normal men. This study shows that chronic prostatitis patients present important alterations in their semen quality parameters, Omi/HtrA2 mRNA and protein levels of spermatozoa. We speculate that the inflammatory process involved may affect male fertility by release of proapoptotic protein Omi/HtrA2.

Burkholderia cenocepacia ZmpB is a broad-specificity zinc metalloprotease involved in virulence

In previous studies we characterized the Burkholderia cenocepacia ZmpA zinc metalloprotease. In this study, we determined that B. cenocepacia has an additional metalloprotease, which we designated ZmpB. The zmpB gene is present in the same species as zmpA and was detected in B. cepacia, B. cenocepacia, B. stabilis, B. ambifaria, and B. pyrrocinia but was absent from B. multivorans, B. vietnamiensis, B. dolosa, and B. anthina. The zmpB gene was expressed, and ZmpB was purified from Escherichia coli by using the pPROEXHTa His(6) Tag expression system. ZmpB has a predicted preproenzyme structure typical of thermolysin-like proteases and is distantly related to Bacillus cereus bacillolysin. ZmpB was expressed as a 63-kDa preproenzyme precursor that was autocatalytically cleaved into mature ZmpB (35 kDa) and a 27-kDa prepropeptide. EDTA, 1,10-phenanthroline, and Zn(2+) cations inhibited ZmpB enzyme activity, indicating that it is a metalloprotease. ZmpB had proteolytic activity against alpha-1 proteinase inhibitor, alpha(2)-macrogobulin, type IV collagen, fibronectin, lactoferrin, transferrin, and immunoglobulins. B. cenocepacia zmpB and zmpA zmpB mutants had no proteolytic activity against casein and were less virulent in a rat agar bead chronic infection model, indicating that zmpB is involved in B. cenocepacia virulence. Expression of zmpB was regulated by both the CepIR and CciIR quorum-sensing systems.

Effects of a Single Nucleotide Polymorphism on the Expression of Human Tumor Necrosis Factor-alpha

Tumor necrosis factor (TNF)-alpha plays a prominent role in inflammations and is a proinflammatory cytokine that has been implicated in the pathogenesis of autoimmune and infectious diseases. Recent association studies have found that the TNF-alpha-857T allele was associated with several disorders. Here we demonstrate, with reporter genes under the control of the two allelic TNF-alpha promoters, that the minor allele -857T is a much stronger transcriptional activator than the major allele -857C in RAW264.7 cell line in response to lipopolysaccharide stimulation. However, the result was not consistent in HeLa cell line. Furthermore, for the quantitative analysis of TNF-alpha synthesis between the -857C/C genotype from healthy subjects and the -857C/T genotype from AS patients, the quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay were performed separately. There was no significant difference between the two groups at the level of mRNA and protein. These results show that this polymorphism may have a direct effect on TNF-alpha regulation in a tissue-specific manner, and apart from the polymorphism at -857 in the TNF-alpha promoter, there may be other factors affecting the expression of TNF-alpha.

Differentiating sex chromosomes of the dioecious Spinacia oleracea L. (spinach) by FISH of 45S rDNA

Spinacia oleracea L. (spinach) is a dioecious species with both male and female plants having 2n = 2x = 12 chromosomes, consisting of two large metacentrics, two long subtelocentrics, two short subtelocentrics, two acrocentrics, and four submetacentrics. The location of 45S rDNA was investigated on metaphase chromosomes using fluorescence in situ hybridization (FISH). The numbers of 45S rDNA foci in diploid sets of chromosomes from females was six and from males was five. All the fluorescent foci lay in secondary constrictions and the satellites. Our results indicate that an XY-type sex chromosome system could be present in spinach where the Y chromosome lacks a 45S RNA focus.

Novel method for predicting chemoresistance to paclitaxel in epithelial ovarian cancer patients

15007

Background: No available test exists to guide the selection of effective chemotherapeutic regimen in recurrent ovarian cancer. Preliminary studies in our lab have identified a protein, MyD88, a major component in the inflammatory pathway, to be highly expressed in epithelial ovarian cancer cells that exhibit primary or acquired Paclitaxel chemoresistance. The objective of this study was to develop a sensitive approach that can detect expression of MyD88 in ovarian cancer tissue. We report the development of a test based on Laser capture microdissection that allows detection of MyD88 in a 6000 cell sample. Methods: Tumor tissue was obtained at surgery from epithelial ovarian cancer patients and snap-frozen in liquid nitrogen. Eight micron sections were prepared on polyethylene covered glass slides and tumor cells were dissected with a Laser capture microdissection system. Protein expression was detected by Western blot analysis. Results: Protein expression was detected by Western blot analysis in 1000 microdissected cells. An inverse correlation was observed between MyD88 expression in tumor cells and clinical response to Paclitaxel. Furthermore, this method allows the isolation of CD-45 positive cells from the tumor and analysis of their protein expression. Conclusions: We describe for the first time a method that will allow us to predict chemoresistance. Laser capture microdissection is a powerful technique that can be used to study the protein profile of each of the cellular components present in the tumor microenvironment. This technique will facilitate our understanding of the proteins necessary for tumor growth and may help to identify novel markers or potential protein targets.

No significant financial relationships to disclose.

Efficacy and safety of pemetrexed (P) in elderly cancer patients (pts)

8544

Background: P, a novel multitargeted antifolate, has demonstrated antitumor activity in a broad range of tumor types. Approximately 60% of all new cases of cancer and 70% of all cancer-related deaths occur in the elderly population. However, few studies have specifically analyzed the utility of chemotherapy in this population. The objective of this posthoc analysis was to understand the efficacy and tolerability of pemetrexed (alone or in combination) when used in the elderly cancer population. Methods: Data from three pemetrexed registration trials conducted between April 1999 and February 2003 were pooled together. Pts in these studies were diagnosed with malignant pleural mesothelioma, NSCLC, or advanced pancreatic cancer. Pts receiving P as monotherapy or in combination with another drug (gemcitabine or cisplatin) who received at least one cycle of therapy were included in this analysis (n=764). In all studies, P 500 mg/m2 was administered every 21 days. Demographics, efficacy, and safety data from pts receiving P were stratified by age ± 65 years. Kaplan-Meier method was used to estimate survival and time to PD. Cox regression model was also used to test the survival effect of pemetrexed on age after adjusting for disease stage, performance status, gender, and type of tumors, the prognostic factors considered to influence survival. Results: * P<.05 from fisher’s exact test. The adjusted hazard ratio of elderly patients over younger patients was 1.074 with p-value 0.42. Conclusions: P produced similar treatment effects in older and younger patients and appeared to be well tolerated in the elderly population. CTC grade 3/4 Lab and Non-Lab toxicity between two age groups were similar except, as expected, the elderly group had modestly higher myelosuppression. Non-hematologic toxicities were similar between the two age groups.

[Table: see text]

[Table: see text]

Gemcitabine (G) plus carboplatin (C) at AUC 5 demonstrates reduced grade 4 thrombocytopenia rate compared to AUC 5.5 in first line therapy of patients with advanced stage NSCLC

7130

Background: GC is a commonly used regimen in first-line therapy of advanced stage NSCLC. Various dosing of carboplatin in the GC regimen produces different toxicity profiles. This report summarizes three recent large clinical trials, including the Coalition Trial, using GC regimens that had comparable efficacy to other modern doublets. Methods: Three trials using GC as first-line treatment for advanced NSCLC with recent best response and toxicity data were selected. Pt populations were similarly defined, including measurable or evaluable Stage IIIB (with pleural effusion) or IV disease. All utilized similar 21-d regimens of G 1000 mg/m2 d 1,8 and C AUC 5.5 or 5.0 d1. Results: Despite a grade 4-thrombocytopenia rate of 12% in Trial 1 (Coalition) there was no difference in serious bleeding events compared to the other arms (paclitaxel/carboplatin and paclitaxel/gemcitabine). Discussion: In these three trials, 1126 pts with advanced NSCLC were treated with first-line GC. This database of 743 patients assessed for safety suggests that GC AUC 5 results in a 4.7% (95% CI: 3.3–6.5%) grade 4-thrombocytopenia rate with similar anti-tumor efficacy. The regimen of G 1000 mg/m2 on d1, 8 with C AUC 5 on d1 of a 21-d cycle may be optimal for treatment of advanced NSCLC.

[Table: see text]

[Table: see text]

Upregulation of osteopontin gene expression in diabetic rat proximal tubular cells revealed by microarray profiling

Progression of diabetic nephropathy appears directly related to renal tubulointerstitial injury, but the involved genes are incompletely delineated. To identify such genes, DNA microarray analysis was performed with RNA from renal proximal tubules (RPTs) of streptozotocin-induced diabetic Wistar rats, spontaneously diabetic BioBreeding rats, and rat immortalized renal proximal tubular cells (IRPTCs) exposed to high glucose (25 mM) medium for 2 weeks. Osteopontin (OPN) mRNA expression was quantified by real time-quantitative polymerase chain reaction (RT-qPCR) or conventional reverse transcriptase-polymerase chain reaction (RT-PCR). OPN mRNA expression was upregulated (5-70-fold increase) in diabetic rat RPTs and in IRPTCs chronically exposed to high glucose compared to control RPTs and IRPTCs. High glucose, angiotensin II, phorbol 12-myristate 13-acetate and transforming growth factor-beta 1 (TGF-beta1) stimulated OPN mRNA expression in IRPTCs in a dose- and time-dependent manner. This effect was inhibited by tiron, taurine, diphenylene iodinium, losartan, perindopril, calphostin C, or LY 379196 but not PD123319. IRPTCs overexpressing dominant-negative protein kinase C-beta 1 (PKC-beta1) cDNA or antisense TGF-beta1 cDNA prevented the high glucose effect on OPN mRNA expression. We concluded that high glucose-mediated increases in OPN gene expression in diabetic rat RPTs and IRPTCs are mediated, at least in part, via reactive oxygen species generation, intrarenal rennin-angiotensin system activation, TGF-beta1 expression, and PKC-beta1 signaling.

Case Report: A Left Donor Lung Implanted in the Recipient’s Right Thorax for the Therapy of Pulmonary Fibrosis

A 68-year patient suffering from pulmonary fibrosis underwent single lung transplantation on April 4, 2005. Because the ipsilateral donor lung was severely damaged, we had to implant the contralateral lung--the left lung--to the right thorax, and finally this patient recovered.

Effects of L-malate on physical stamina and activities of enzymes related to the malate-aspartate shuttle in liver of mice

L-malate, a tricarboxylic acid cycle (TCA) intermediate, plays an important role in transporting NADH from cytosol to mitochondria for energy production and may be involved in the beneficial effects of improving physical stamina. In the present study, we investigated the effects of L-malate on the performance of forced swimming time and blood biochemical parameters related to fatigue - blood urea nitrogen (BUN), glucose (Glc), creatine kinase (CK),total protein (TP) and lactic acid (LA). To investigate the effects of L-malate on the malate-aspartate shuttle and energy metabolism in mice, the activities of enzymes related to the malate-aspartate shuttle were measured. L-malate was orally administered to mice continuously for 30 days using a feeding atraumatic needle. The swimming time was increased by 26.1 % and 28.5 %, respectively, in the 0.210 g/kg and 0.630 g/kg L-malate-treated group compared with the control group. There were no differences in the concentrations of Glc, BUN and TP between the L-malate-treated groups and the control groups. However, the levels of CK were significantly decreased in the L-malate-treated groups. The results predict a potential benefit of L-malate for improving physical stamina and minimizing muscle damage during swimming exercise. The activities of cytosolic and mitochondrial malate dehydrogenase were significantly elevated in the L-malate-treated group compared with the control group. These enzymatic activities may be useful indicators for evaluating changes affecting the malate-aspartate shuttle and energy metabolism in the liver of mice.

Multiwalled Carbon Nanotube Supported PtRu for the Anode of Direct Methanol Fuel Cells

The activity of the methanol oxidation reaction of a multiwalled carbon nanotube (MWCNT)-supported PtRu catalyst was investigated and compared with the Vulcan XC-72 carbon-supported catalyst. The PtRu nanoparticles with 1:1 and 7:3 atomic ratios (with similar PtRu loadings and morphological structures) were deposited both on the MWCNTs and on the carbon. Cyclicvoltammetry results demonstrated that the MWCNT-supported PtRu catalyst exhibited a higher mass activity (mA mg(-1) of PtRu) for the methanol oxidation reaction than the carbon-supported PtRu under the condition that both catalysts possess more or less the same PtRu loadings, particle sizes, dispersions, and electrochemical surface area. The direct methanol fuel cell performance test data showed that MWCNT-supported PtRu catalysts yielded about 35-39% higher power densities than the carbon-supported PtRu.