Nuclear Factor kappa B (NF-κB) is a transcription factor family critical in the activation of pro- inflammatory responses. The NF-κB pathway is regulated by oxidant-induced post-translational ...modifications. Protein S-glutathionylation, or the conjugation of the antioxidant molecule, glutathione to reactive cysteines inhibits the activity of inhibitory kappa B kinase beta (IKKβ), among other NF-κB proteins. Glutathione S-transferase Pi (GSTP) is an enzyme that has been shown to catalyze protein S-glutathionylation (PSSG) under conditions of oxidative stress. The objective of the present study was to determine whether GSTP regulates NF-κB signaling, S-glutathionylation of IKK, and subsequent pro-inflammatory signaling. We demonstrated that, in unstimulated cells, GSTP associated with the inhibitor of NF-κB, IκBα. However, exposure to LPS resulted in a rapid loss of association between IκBα and GSTP, and instead led to a protracted association between IKKβ and GSTP. LPS exposure also led to increases in the S-glutathionylation of IKKβ. SiRNA-mediated knockdown of GSTP decreased IKKβ-SSG, and enhanced NF-κB nuclear translocation, transcriptional activity, and pro-inflammatory cytokine production in response to lipopolysaccharide (LPS). TLK117, an isotype-selective inhibitor of GSTP, also enhanced LPS-induced NF-κB transcriptional activity and pro-inflammatory cytokine production, suggesting that the catalytic activity of GSTP is important in repressing NF-κB activation. Expression of both wild-type and catalytically-inactive Y7F mutant GSTP significantly attenuated LPS- or IKKβ-induced production of GM-CSF. These studies indicate a complex role for GSTP in modulating NF-κB, which may involve S-glutathionylation of IKK proteins, and interaction with NF-κB family members. Our findings suggest that targeting GSTP is a potential avenue for regulating the activity of this prominent pro-inflammatory and immunomodulatory transcription factor.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Glutathione transferases (GSTs) are often overexpressed in tumors and frequently correlated to bad prognosis and resistance against a number of different anticancer drugs. To selectively target these ...cells and to overcome this resistance we previously have developed prodrugs that are derivatives of existing anticancer drugs (e.g., doxorubicin) incorporating a sulfonamide moiety. When cleaved by GSTs, the prodrug releases the cytostatic moiety predominantly in GST overexpressing cells, thus sparing normal cells with moderate enzyme levels. By modifying the sulfonamide it is possible to control the rate of drug release and specifically target different GSTs. Here we show that the newly synthesized compounds, 4-acetyl-2-nitro-benzenesulfonyl etoposide (ANS–etoposide) and 4-acetyl-2-nitro-benzenesulfonyl doxorubicin (ANS–DOX), function as prodrugs for GSTA1 and MGST1 overexpressing cell lines. ANS–DOX, in particular, showed a desirable cytotoxic profile by inducing toxicity and DNA damage in a GST-dependent manner compared to control cells. Its moderate conversion of 500 nmol/min/mg, as catalyzed by GSTA1, seems hereby essential since the more reactive 2,4-dinitrobenzenesulfonyl doxorubicin (DNS–DOX) (14000 nmol/min/mg) did not display a preference for GSTA1 overexpressing cells. DNS–DOX, however, effectively killed GSTP1 (20 nmol/min/mg) and MGST1 (450 nmol/min/mg) overexpressing cells as did the less reactive 4-mononitrobenzenesulfonyl doxorubicin (MNS–DOX) in a MGST1-dependent manner (1.5 nmol/min/mg) as shown previously. Furthermore, we show that the mechanism of these prodrugs involves a reduction in GSH levels as well as inhibition of the redox regulatory enzyme thioredoxin reductase 1 (TrxR1) by virtue of their electrophilic sulfonamide moiety. TrxR1 is upregulated in many tumors and associated with resistance to chemotherapy and poor patient prognosis. Additionally, the prodrugs potentially acted as a general shuttle system for DOX, by overcoming resistance mechanisms in cells. Here we propose that GST-dependent prodrugs require a conversion rate “window” in order to selectively target GST overexpressing cells, while limiting their effects on normal cells. Prodrugs are furthermore a suitable system to specifically target GSTs and to overcome various drug resistance mechanisms that apply to the parental drug.
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IJS, KILJ, NUK, PNG, UL, UM
Abstract Background After orchidectomy, the standard management options available for stage I seminoma are surveillance, adjuvant radiotherapy, or adjuvant chemotherapy. The optimal follow-up ...protocol for surveillance is yet to be determined but includes frequent chest radiography (CXR) and computed tomography (CT) scan of the abdomen and pelvis (CT-AP). Objective The purpose of this study was to identify the modality that first detected relapse and to assess the value of the CXR in this setting. Design, setting, and participants Five hundred twenty-seven patients with histologically confirmed stage I testicular seminoma were managed with surveillance at our institution between 1982 and 2005. Routine CXRs were performed with each CT-AP and were done every 4–6 mo for 7 yr and annually thereafter. The median follow-up was 72 mo (range: 1–193). Measurements Measurements included the 5-yr relapse rate, overall survival, and disease-free survival to determine the modality that first detected relapse disease. Results and limitations The 5-yr actuarial relapse rate for the 527 patients was 14%. The 5-yr disease-free survival and overall survival were 85.7% and 98.6%, respectively. Seventy-three patients (97.3%) had an abnormal CT-AP and a normal CXR at relapse. One patient (1.3%) had an abnormal CT-AP with pulmonary metastasis on CXR and CT chest scan, and one patient (1.3%) had a biopsy-proven inguinal node metastasis with a normal CXR. No patient had a normal CT-AP or physical examination with an abnormal CXR at relapse. This is a single-center retrospective study based on a relatively small number of relapses and may be subject to bias. Confirmation of these results from other studies would be useful for wider clinical applicability. Conclusions All except one relapse were detected by CT-AP with no relapses detected on CXR alone; therefore, CXR may be omitted as routine imaging in surveillance protocols.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
5.
Spermatocytic seminoma: A review CHUNG, Peter W. M; BAYLEY, Andrew J. S; SWEET, Joan ...
European urology,
04/2004, Volume:
45, Issue:
4
Journal Article
Peer reviewed
Spermatocytic seminoma is a rare testicular tumour that has an extremely low rate of metastasis. We present a review of the management of this malignancy at our institution.
Between 1981 and 1999, ...771 patients were treated at our institution for testicular seminoma. Of these, 13 had spermatocytic seminoma; one was excluded as he had treatment elsewhere. All patients were initially diagnosed at other hospitals and subsequently referred for management and had their pathology reviewed locally prior to any treatment.
All patients had stage I disease, 5 patients received radiotherapy to the para-aortic and pelvic nodes, the other 7 were followed on a surveillance program. The median age was 62 years. With a median follow-up of 8.5 years no relapses were observed. Some patients exhibited adverse histological features associated with increased risk of relapse in seminoma including rete testis invasion and large primary tumour size.
Spermatocytic seminoma may occur in younger patients and may not be restricted to the older population as commonly reported. Surveillance following orchidectomy is the preferred management option.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Summary Background Etrolizumab is a humanised monoclonal antibody that selectively binds the β7 subunit of the heterodimeric integrins α4β7 and αEβ7. We aimed to assess etrolizumab in patients with ...moderately-to-severely active ulcerative colitis. Methods In this double-blind, placebo-controlled, randomised, phase 2 study, patients with moderately-to-severely active ulcerative colitis who had not responded to conventional therapy were recruited from 40 referral centres in 11 countries. Eligible patients (aged 18–75 years; Mayo Clinic Score MCS of 5 of higher or ≥6 in USA; and disease extending 25 cm or more from anal verge) were randomised (1:1:1) to one of two dose levels of subcutaneous etrolizumab (100 mg at weeks 0, 4, and 8, with placebo at week 2; or 420 mg loading dose LD at week 0 followed by 300 mg at weeks 2, 4, and 8), or matching placebo. The primary endpoint was clinical remission at week 10, defined as MCS of 2 or less (with no individual subscore of >1), analysed in the modified intention-to-treat population (mITT; all randomly assigned patients who had received at least one dose of study drug, had at least one post-baseline disease-activity assessment, and had a centrally read screening endoscopic subscore of ≥2). This study is registered with ClinicalTrials.gov , number NCT01336465. Findings Between Sept 2, 2011, and July 11, 2012, 124 patients were randomly assigned, of whom five had a endoscopic subscore of 0 or 1 and were excluded from the mITT population, leaving 39 patients in the etrolizumab 100 mg group, 39 in the etrolizumab 300 mg plus LD group, and 41 in the placebo group for the primary analyses. No patients in the placebo group had clinical remission at week 10, compared with eight (21% 95% CI 7–36) patients in the etrolizumab 100 mg group (p=0·0040) and four (10% 0·2–24) patients in the 300 mg plus LD group (p=0·048). Adverse events occurred in 25 (61%) of 41 patients in the etrolizumab 100 mg group (five 12% of which were regarded as serious), 19 (48%) of 40 patients in the etrolizumab 300 mg plus LD group (two 5% serious), and 31 (72%) of 43 patients in the placebo group (five 12% serious). Interpretation Etrolizumab was more likely to lead to clinical remission at week 10 than was placebo. Therefore, blockade of both α4β7 and αEβ7 might provide a unique therapeutic approach for the treatment of ulcerative colitis, and phase 3 studies have been planned. Funding Genentech.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Idiopathic pulmonary fibrosis (IPF) is a debilitating lung disease characterized by excessive collagen production and fibrogenesis. Apoptosis in lung epithelial cells is critical in IPF pathogenesis, ...as heightened loss of these cells promotes fibroblast activation and remodeling. Changes in glutathione redox status have been reported in IPF patients. S-glutathionylation, the conjugation of glutathione to reactive cysteines, is catalyzed in part by glutathione-
-transferase π (GSTP). To date, no published information exists linking GSTP and IPF to our knowledge. We hypothesized that GSTP mediates lung fibrogenesis in part through FAS S-glutathionylation, a critical event in epithelial cell apoptosis. Our results demonstrate that GSTP immunoreactivity is increased in the lungs of IPF patients, notably within type II epithelial cells. The FAS-GSTP interaction was also increased in IPF lungs. Bleomycin- and AdTGFβ-induced increases in collagen content, α-SMA, FAS S-glutathionylation, and total protein S-glutathionylation were strongly attenuated in
mice. Oropharyngeal administration of the GSTP inhibitor, TLK117, at a time when fibrosis was already apparent, attenuated bleomycin- and AdTGFβ-induced remodeling, α-SMA, caspase activation, FAS S-glutathionylation, and total protein S-glutathionylation. GSTP is an important driver of protein S-glutathionylation and lung fibrosis, and GSTP inhibition via the airways may be a novel therapeutic strategy for the treatment of IPF.
Heterotopic ossification is a frequently encountered clinical and radiographic entity. There are no previous reports in the English literature of heterotopic ossification after arthroscopically ...assisted ligament reconstructions for knee dislocations. Further, a link between the PCL reconstruction and posterior capsular ossification has not been heretofore recognized. Our three cases should raise the clinical awareness of such an entity.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
The synthesis, in vitro activities, and pharmacokinetics of a series of azepanone-based inhibitors of the cysteine protease cathepsin K (EC 3.4.22.38) are described. These compounds show improved ...configurational stability of the C-4 diastereomeric center relative to the previously published five- and six-membered ring ketone-based inhibitor series. Studies in this series have led to the identification of 20, a potent, selective inhibitor of human cathepsin K (K i = 0.16 nM) as well as 24, a potent inhibitor of both human (K i = 0.0048 nM) and rat (K i,app = 4.8 nM) cathepsin K. Small-molecule X-ray crystallographic analysis of 20 established the C-4 S stereochemistry as being critical for potent inhibition and that unbound 20 adopted the expected equatorial conformation for the C-4 substituent. Molecular modeling studies predicted the higher energy axial orientation at C-4 of 20 when bound within the active site of cathepsin K, a feature subsequently confirmed by X-ray crystallography. Pharmacokinetic studies in the rat show 20 to be 42% orally bioavailable. Comparison of the transport of the cyclic and acyclic analogues through CaCo-2 cells suggests that oral bioavailability of the acyclic derivatives is limited by a P-glycoprotein-mediated efflux mechanism. It is concluded that the introduction of a conformational constraint has served the dual purpose of increasing inhibitor potency by locking in a bioactive conformation as well as locking out available conformations which may serve as substrates for enzyme systems that limit oral bioavailability.
In situ X-ray absorption spectroscopy at the Pd L3 edge was applied to determine the particle size effect on the formation of palladium hydride and on surface hydrogen adsorption at room temperature. ...Pd L3 edge XANES spectra allow direct detection of hydride formation via a characteristic spectral feature caused by the formation of a Pd-H anti-bonding state. This feature showed strong particle size dependence. The L3 edge spectra were reproduced using full multiple scattering analysis and density of states calculations and the contributions of bulk-dissolved and surface hydrogen to the XANES spectra could be distinguished. The ratio of hydrogen on the surface versus that in the bulk increased with decreasing particle size, and smaller particles dissolved less hydrogen.
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