Association of the advanced lung cancer inflammation index (ALI) with immune checkpoint inhibitor efficacy in patients with advanced non-small-cell lung cancer.

BACKGROUND: The advanced lung cancer inflammation index [ALI: body mass index × serum albumin/neutrophil-to-lymphocyte ratio (NLR)] reflects systemic host inflammation, and is easily reproducible. We hypothesized that ALI could assist guidance of non-small-cell lung cancer (NSCLC) treatment with immune checkpoint inhibitors (ICIs). PATIENTS AND METHODS: This retrospective study included 672 stage IV NSCLC patients treated with programmed death-ligand 1 (PD-L1) inhibitors alone or in combination with chemotherapy in 25 centers in Greece and Germany, and a control cohort of 444 stage IV NSCLC patients treated with platinum-based chemotherapy without subsequent targeted or immunotherapy drugs. The association of clinical outcomes with biomarkers was analyzed with Cox regression models, including cross-validation by calculation of the Harrell's C-index. RESULTS: High ALI values (>18) were significantly associated with longer overall survival (OS) for patients receiving ICI monotherapy [hazard ratio (HR) = 0.402, P < 0.0001, n = 460], but not chemo-immunotherapy (HR = 0.624, P = 0.111, n = 212). Similar positive correlations for ALI were observed for objective response rate (36% versus 24%, P = 0.008) and time-on-treatment (HR = 0.52, P < 0.001), in case of ICI monotherapy only. In the control cohort of chemotherapy, the association between ALI and OS was weaker (HR = 0.694, P = 0.0002), and showed a significant interaction with the type of treatment (ICI monotherapy versus chemotherapy, P < 0.0001) upon combined analysis of the two cohorts. In multivariate analysis, ALI had a stronger predictive effect than NLR, PD-L1 tumor proportion score, lung immune prognostic index, and EPSILoN scores. Among patients with PD-L1 tumor proportion score ≥50% receiving first-line ICI monotherapy, a high ALI score >18 identified a subset with longer OS and time-on-treatment (median 35 and 16 months, respectively), similar to these under chemo-immunotherapy. CONCLUSIONS: The ALI score is a powerful prognostic and predictive biomarker for patients with advanced NSCLC treated with PD-L1 inhibitors alone, but not in combination with chemotherapy. Its association with outcomes appears to be stronger than that of other widely used parameters. For PD-L1-high patients, an ALI score >18 could assist the selection of cases that do not need addition of chemotherapy.

The role of socio-demographic factors in depression and anxiety of patients on hemodialysis: an observational cross-sectional study.

PURPOSE: Depression and anxiety have high prevalence in patients on hemodialysis and are strongly associated with socio-economic factors. The aim of this study was to evaluate the prevalence of depression and anxiety in hemodialyzed patients in Greece and its association with socio-demographic factors. METHODS: Four hundred and fourteen (414) patients on hemodialysis (262 males and 152 females) from 24 dialysis centers in Greece participated in this observational cross-sectional study. Mean age was 63.54 (54.06-72.41), and mean time of dialysis treatment was 36 (16-72) months. Depression and anxiety were assessed by the state-trait anxiety inventory (STAI), the beck depression inventory (BDI) and the hospital anxiety and depression scale (HADS). Multinomial logistic regression was performed to estimate the factors being independently associated with anxiety and depression levels (HADS scale). Multiple linear regression was performed to estimate the factors being independently associated with BDI and STAI. RESULTS: From a total of 414 participants, (29.4%, n = 122) had depression and 35.9% (n = 149) had anxiety. Depression and anxiety were significantly associated with females, low level of education, increased patients' age, retirement, poor financial situation, marital status and co-morbidities. CONCLUSION: The overall study findings indicated a significant correlation between the levels of anxiety and depression in patients on hemodialysis. Patients with high levels of anxiety had higher levels of depression and those with high depression scores had higher anxiety scores.

Cytoreductive surgery and HIPEC in recurrent epithelial ovarian cancer: a prospective randomized phase III study.

BACKGROUND: The current treatment of ovarian cancer consists of cytoreductive surgery (CRS) and systemic chemotherapy. The aim of this study was to examine if hyperthermic intraperitoneal chemotherapy (HIPEC) is an alternative modality to treat this category of patients along with a second attempt of surgical resection and second- or third-line systemic chemotherapy afterward. METHODS: In an 8-year period (2006-2013), 120 women with advanced ovarian cancer (International Federation of Gynecology and Obstetrics [FIGO] IIIc and IV) who experienced disease recurrence after initial treatment with conservative or debulking surgery and systemic chemotherapy were randomized into two groups. Group A comprised 60 patients treated with CRS followed by HIPEC and then systemic chemotherapy. Group B comprised 60 patients treated with CRS only and systemic chemotherapy. RESULTS: The mean survival for group A was 26.7 versus 13.4 months in group B (p < 0.006). Three-year survival was 75 % for group A versus 18 % for group B (p < 0.01). In the HIPEC group, the mean survival was not different between patients with platinum-resistant disease versus platinum-sensitive disease (26.6 vs. 26.8 months). On the other hand, in the non-HIPEC group, there was a statistically significant difference between platinum-sensitive versus platinum-resistant disease (15.2 vs. 10.2 months, p < 0.002). Complete cytoreduction was associated with longer survival. Patients with a peritoneal cancer index score of <15 appeared also to have longer survival. CONCLUSIONS: The use of HIPEC along with the extent of the disease and the extent of cytoreduction play an important role in the survival of patients with recurrence in an initially advanced ovarian cancer.

Expression of Ser729 phosphorylated PKCepsilon in experimental crescentic glomerulonephritis: an immunohistochemical study.

PKCε, a DAG-dependent, Ca2+- independent kinase attenuates extent of fibrosis following tissue injury, suppresses apoptosis and promotes cell quiescence. In crescentic glomerulonephritis (CGN), glomerular epithelial cells (GEC) contribute to fibro-cellular crescent formation while they also transdifferentiate to a mesenchymal phenotype. The aim of this study was to assess PKCε expression in CGN. Using an antibody against PKC-ε phosphorylated at Ser729, we assessed its localization in rat model of immune-mediated rapidly progressive CGN. In glomeruli of control animals, pPKCε was undetectable. In animals with CGN, pPKCε was expressed exclusively in glomerular epithelial cells (GEC) and in GEC comprising fibrocellular crescents that had acquired a myofibroblast-type phenotype. In non-immune GEC injury induced by puromycin aminonucleoside and resulting in proteinuria of similar magnitude as in CGN, pPKCε expression was absent. There was constitutive pPKCε expression in distal convoluted tubules, collecting ducts and thick segments of Henley's loops in both control and experimental animals. We propose that pPKCε expression occurring in GEC and in fibrocellular crescentic lesions in CGN may facilitate PKCε dependent pathologic processes.

Advances in thymic carcinoma diagnosis and treatment: a review of literature.

Thymomas account for up to 50 % of anterior mediastinal neoplasms with an incidence of 0.13 per 100,000 person-years in the USA. Thymic carcinoma is a rare malignancy of the thymus gland distinguished from thymomas as it has a more invasive and metastasizing potential conferring poor prognosis. Due to the rarity of thymic carcinoma and the great variety of its histological subtypes, there is no solid evidence on optimal staging, imaging and treatment guidelines. Herein, we systematically review the literature on current clinical practice with regard to diagnostic evaluation, histopathological assessment, management and treatment of squamous thymic carcinoma.

Adjuvant platinum-based chemotherapy in patients with epithelial ovarian cancer: prognostic factors and final outcome.

PURPOSE: epithelial ovarian cancer (OVCA) prognosis depends on the clinical stage, histological grade and surgical cytoreduction. Our goal was to retrospectively analyze several prognostic factors in relation with the final outcome in patients with OVCA subjected to adjuvant platinum (PL)- based chemotherapy (CT). METHODS: three hundred OVCA patients were treated at the Department of Medical Oncology A', "Metaxa" Cancer Hospital, between 11/1989-3/2010. Of those, analyzed were patients with R0 debulking operation, treated with adjuvant PL-based CT. Their clinico/imaging/pathological findings and serum tumor marker CA 125 levels were analyzed and related to relapse rate (RR), progression-free survival (PFS) and overall survival (OS). RESULTS: out of 53 R0 OVCA patients 35 (66%) experienced long-term PFS (median follow up time 63 months, range 5-195(+)) and 18 (34%) relapsed after a median of 19 months. Fifteen of the 18 relapsing patients were treated with first-line CT. Twelve (80%) of them were PL-sensitive and 3 (20%) PL-resistant. Their median PFS was 9 and 3 months in PL-sensitive and PL-resistant cases, respectively (p=0.073). Statistical analysis of prognostic factors demonstrated FIGO stage and abnormal postoperative CA 125 values as significant. Patients with FIGO stage III had significantly shorter PFS (p=0.002) and OS (p=0.078) than those in earlier stages, and patients with abnormal postoperative CA 125 values had significantly worse PFS (p=0.017) but not OS (p=0.386) than those with normal values. Age, histological subtype and grade did not affect PFS and OS. CONCLUSION: FIGO stage and abnormal postoperative CA 125 have prognostic significance in OVCA patients after R0 surgical therapy and adjuvant PL-based CT. Patients with PL-sensitive disease achieved better results during therapy for relapse.

Clinicopathological features of primary fallopian tube carcinoma: a single institution experience.

PURPOSE OF INVESTIGATION: Primary fallopian tube carcinoma (PFTC) is a rare malignancy with only few data existing on the impact of prognostic factors. METHODS: We retrospectively analyzed 26 patients. Tissue blocks were reviewed and sections were stained for vascular endothelial growth factor (VEGF), matrix metalloproteinases 2 and 9 (MMP-2, MMP-9), tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1, TIMP-2), c-erbB-2, estrogen (ER), and progesterone receptors (PgR). RESULTS: Reactivity for VEGF, ER, PgR, MMP-2, MMP-9, TIMP-1, TIMP-2 and c-erbB-2 was observed in 85%, 46%, 27%, 11.5%, 58%, 0%, 23% and 8% of specimens, respectively. None of the markers studied displayed prognostic significance. Regarding clinical prognostic factors, the hazard ratio (HR) for progression and death for patients with tumor residuum > 2 cm was 5.24 (p < 0.01) and 11.19 (p < 0.005), respectively. Patients with advanced stage disease had a HR of 12.55 (p < 0.05) for progression, while the HR for death was not found to be statistically significant. CONCLUSION: None of the biomarkers studied seems to influence survival. Early-stage disease and optimal debulking are associated with improved outcome.

Cisplatin-based chemotherapy for merkel cell carcinoma of the skin.

PURPOSE: Merkel cell carcinoma (MCC), a rare tumor of the skin with aggressive behavior, is usually fatal when advanced disease is present. The role of chemotherapy (CT) in the treatment of patients with MCC is unclear. METHODS: Over 15 years, 9 patients with locally advanced or metastatic disease were treated with carboplatin (CBDCA) (300 mg/m(2) of AUC 5 on Day 1) and etoposide (VP-16) (100 mg/m(2) on Days 1-3) every 3 weeks. As second-line CT, cisplatin (CDDP) (60-100 mg/m(2)), ifosfamide (IFO) (3-5 g/m(2)) and epirubicin (EPI) (30-50 mg/m(2)) were utilized. RESULTS: Of the 3 patients who received adjuvant therapy, one achieved complete response after 108+ months with second-line chemotherapy and radiotherapy, despite a brief relapse; 2 patients remain disease-free after 84+ and 108+ months. Of the 6 patients with locally advanced or metastatic disease who were treated with first-line chemotherapy, one (16.6 percent) achieved a complete response and 3 (50 percent) achieved partial response, for an overall response rate of 66.6 percent. Two patients (one with complete and one with partial response) received subsequent radiotherapy, following which complete response was achieved. Of the 2 complete responders, one patient remains disease-free after 56+ months. The median overall survival from the time of initial diagnosis for the whole group was 56 months (range 15-114 months); the median overall survival from the initiation of chemotherapy was 18 months (range 6-108+). Local recurrences and soft tissue metastases responded better than visceral metastases. Patients with partial response and no response had rapid disease progression and fatality, despite second-line chemotherapy and/or radiotherapy. CONCLUSION: MCC appears to be chemosensitive but can progress rapidly with fatal outcomes. Although the rarity of these tumors precludes randomized trials, a common treatment plan should be utilized by those treating MCC. This may allow some conclusions regarding the optimum treatment of patients with MCC to be drawn in the future.

Dermatomyositis associated with breast cancer.

An increased risk of underlying malignancy has been found in patients with dermatomyositis (DM). The risk is increased even in patients with DM aged 45 or younger and remains high for many years after diagnosis. Breast carcinoma does not represent the most common solid tumor associated with this autoimmune disorder. In the present report, two new cases of DM associated with breast cancer are described, together with an extensive literature review.

Finasteride: a long-term follow-up in the treatment of recurrent hematuria associated with benign prostatic hyperplasia.

OBJECTIVES: To assess the effectiveness and long-term results after finasteride treatment of recurrent hematuria associated with benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: The study comprised 80 patients, aged 62-86 (mean 74) years, of whom 50 received finasteride 5 mg once daily for 4 years and 30 were used as controls. Patients with malignancy, severe hepatic or renal failure and hematologic disorders were excluded. Patients were divided into 3 groups according to the severity of hematuria (minor, moderate, severe). All patients were followed up at 3, 12, 24 and 48 months. RESULTS: The follow-up ranged from 8 to 48 (mean 22) months in the finasteride group and 3-42 (mean 23) months in the control group. Hematuria recurrence rates were 6/50 (12%) and 23/30 (77%) in the finasteride and control groups, respectively. Surgical treatment was needed in 6 patients of the finasteride group and 19 of the control group. Patients with minor hematuria experienced no recurrence of symptoms in the finasteride group in contrast to 13 of 17 patients in the control group. For the patients with moderate hematuria, recurrence of symptoms was observed in 3 of 13 in the finasteride group and 3 of 5 in the control group. Three of six patients with severe hematuria had a recurrence of symptoms after finasteride treatment in contrast to 7 of 8 in the control group. CONCLUSION: Finasteride has proved to be a safe, well tolerable and effective medication in reducing or preventing recurrent hematuria related to BPH.

Regulation of human P2X1 promoter activity by beta helix-loop-helix factors in smooth muscle cells.

We isolated and characterized genomic clones of the human P2X1 receptor (hP2X1) gene in an effort to understand its tissue specific expression. The hP2X1 gene contains 12 exons spanning 20 kb, with exon sizes ranging from 59 to 143 bp. A 385 bp upstream fragment promoted hP2X1 gene expression in smooth muscle (A7R5 and primary trachealis) and fibroblast (NIH3T3) cell lines, and mutation of a consensus E box sequence (CACCTG) within this fragment (-340 to -345) did not alter basal promoter activity. However, co-transfected bHLH factors regulated activity of the 385 bp minimal P2X1 promoter in a tissue-specific manner. E12 expression inhibited and ITF2b augmented activity in A7R5 cells, but had no effect in NIH3T3 cells. ITF2a, Myo-D, and Id1 proteins had no effect on either cell line, but co-expression of ITF2a blocked E12 inhibition in A7R5 cells, while ITF2b failed to reverse the inhibition. Northern analysis of A7R5 RNA identified high levels of E12 and ITF2b transcripts, and gel shift assays using A7R5 and NIH3T3 nuclear extracts indicated the formation of a protein-DNA complex with an oligonucleotide corresponding to -330 and -348, which was abolished by base substitutions within the E box motif. Our results identify a critical E box response element in the hP2X1 promoter that binds bHLH factors and demonstrate smooth muscle specific transcriptional regulation by E proteins.

Induction of heme oxygenase 1 in radiation nephropathy: role of angiotensin II.

Datta, P. K., Moulder, J. E., Fish, B. L., Cohen, E. P. and Lianos, E. A. Induction of Heme Oxygenase 1 in Radiation Nephropathy: Role of Angiotensin II. Radiat. Res. 155, 734-739 (2001). In a rat model of radiation-induced nephropathy, we investigated changes in expression of heme oxygenase 1 (Hmox1, also known as HO-1), an enzyme that catalyzes conversion of heme into biliverdin, carbon monoxide and iron. The study explored whether radiation induces Hmox1 expression in the irradiated kidney and whether angiotensin II (AII) mediates Hmox1 expression in glomeruli isolated from irradiated kidneys. To assess the effects of radiation on Hmox1 expression, rats received 20 Gy bilateral renal irradiation and were randomized to groups receiving an AII type 1 (AT(1)) receptor antagonist (L-158,809) or no treatment. Drug treatment began 9 days prior to bilateral renal irradiation and continued for the duration of the study. Estimation of Hmox1 levels in glomerular protein lysates assessed by Western blot analysis revealed a significant increase in Hmox1 protein at 50 and 65 days postirradiation. In animals treated with the AT(1) receptor antagonist, there was no induction of Hmox1, suggesting that AII may be a mediator of Hmox1 induction. To confirm that AII stimulates Hmox1 expression, animals were infused with 200, 400 or 800 ng/kg min(-1) of AII for 18-19 days, and Hmox1 protein levels in glomeruli were assessed. There was a significant induction of Hmox1 in glomeruli of animals infused with 800 ng/kg min(-1) of AII. These studies demonstrate that glomerular Hmox1 expression is elevated in the middle phase of radiation nephropathy and that AII can increase glomerular Hmox1 levels.

Heme oxygenase isoform-specific expression and distribution in the rat kidney.

BACKGROUND: The heme oxygenase (HO) genes, HO-1 and HO-2, are the limiting steps in heme degradation and in the regulation of renal heme-dependent enzymes. Previously we reported that selective overexpression of renal HO-1 resulted in a decrease of microsomal heme and the cytochrome P450-dependent arachidonic acid metabolite, 20 HETE, a vasoconstrictor. The present study was undertaken to explore the relative expression and contribution of each of the HO isoforms to HO activity in the rat kidney. METHODS AND RESULTS. Renal HO activity increased above control levels after an injection of the inducers of HO activity, heme or SnCl2. Stannous Mesoporphyrin (SnMP), a nonselective inhibitor of HO, when used alone or in combination with heme or SnCl2, decreased HO activity. Heme alone and combined with SnCl2 decreased the levels of heme content by 13 and 35%, respectively. Western blot analysis showed that both SnCl2 and heme readily induced HO-1 protein, whereas HO-2 was constitutively expressed. Immunohistochemistry showed the distribution of the HO-1 isoform primarily in proximal convoluted tubules. Western blot analysis exhibited relatively higher levels of HO-1 in isolated proximal tubules and relatively higher HO-2 levels in the thick ascending limbs of the loop of Henle and preglomerular arterioles. In vivo administration of HO-1 and HO-2 antisense oligodeoxynucleotides further confirmed that HO-2, but not HO-1, contributed to the basal HO activity; however, following induction of HO with heme, antisense to HO-1, but not to HO-2, inhibited the induced levels of HO activity. CONCLUSION: These results suggest that HO-2 is constitutively expressed in the rat kidney mainly within tubular and arteriolar structures, and its activity may modulate physiological function under basal conditions. On the other hand, the basal levels of expression of HO-1 in the rat kidney are relatively low, and its contribution to HO activity and the regulation of hemoproteins such as cytochrome P450 become apparent only under pathophysiological conditions causing HO induction.

Effects of all-trans-retinoic acid (atRA) on inducible nitric oxide synthase (iNOS) activity and transforming growth factor beta-1 production in experimental anti-GBM antibody-mediated glomerulonephritis.

Sustained high output release of Nitric oxide (NO) as result of activation of inducible nitric oxide synthase (iNOS), and increased production of the antiproliferative/profibrotic cytokine transforming growth factor-beta1 (TGF-beta1) are well documented in glomerulonephritis. Modulation of iNOS activity and of TGF-beta1 production can therefore be viewed as anti-inflammatory strategies. The present study employed all-trans retinoic acid (atRA) which is known to have anti-inflammatory effects and to modulate expression of iNOS and TGF-beta1, in order to explore its effect on iNOS enzyme activity and TGF-beta1 production in anti-GBM antibody induced glomerulonephritis. Glomerulonephritis was induced in Lewis rats by injection of anti-GBM antibody. A group of nephritic rats were given daily administration of atRA for 14-16 days. Extent of proteinuria was assessed by measuring urine protein and creatinine excretion. iNOS enzyme activity was measured by calculating conversion of L[14C]arginine to L-[14C]citrulline in glomerular protein lysates. Levels of TGF-beta1 in glomerular protein lysates were measured by quantitative ELISA. Levels of proliferating nuclear antigen (PCNA), TGF-beta receptor II (TGFbeta-RII), and fibronectin were assessed by Western blot analysis. Glomerular iNOS activity in atRA treated nephritic animals was attenuated in comparison to that in nephritic controls that were not. Glomerular expression of PCNA was also reduced. Levels of TGF-beta1 were increased in glomeruli of atRA treated nephritic animals. In these animals, there was no change in glomerular levels of TGF-beta receptor II (TGFbeta-RII) or fibronectin. and there was no reduction in urine protein excretion. These results suggest that atRA attenuates iNOS activity and proliferation in glomeruli of nephritic animals. The failure of atRA treatment to reduce proteinuria could be due to the increase in TGF-beta1 levels and to inhibition of iNOS-driven NO production.

Heme oxygenase-1 induction attenuates inducible nitric oxide synthase expression and proteinuria in glomerulonephritis.

In glomerulonephritis, there is intraglomerular activation of inducible nitric oxide synthase (iNOS) leading to high output production of nitric oxide (NO). This can result in supraphysiologic amounts of NO and cause oxidative injury. It is unknown whether mechanisms of cellular defense against NO-mediated injury exist. Induction of the heme catabolizing enzyme heme oxygenase-1 (HO-1), which generates biliverdin, carbon monoxide (CO), and iron (Fe), may provide such a mechanism, as CO and Fe are two negative modulators of iNOS activity and expression. This study assessed whether upregulation of HO-1 by a specific inducer, hemin, negatively modulates iNOS expression and activity in anti-glomerular basement membrane antibody-mediated glomerulonephritis. Glomerular HO-1 expression in nephritic animals was upregulated by treatment with hemin (30 micromol/kg body wt). iNOS and HO-1 mRNA expression were assessed by reverse transcription-PCR of glomerular total RNA from nephritic animals or nephritic animals pretreated with hemin. iNOS activity in glomeruli was measured by assessing conversion of [14C] L-arginine to [14C] L-citrulline. HO-1 protein levels in glomeruli were assessed by Western blot analysis. The effect of hemin treatment on monocyte/macrophage infiltration was assessed by enumeration of ED-1-positive cells in nephritic glomeruli. iNOS and HO-1 were coinduced in nephritic glomeruli. Hemin treatment of nephritic animals resulted in upregulation of glomerular HO-1 levels and a two- to threefold reduction in glomerular iNOS mRNA levels. iNOS activity in glomeruli was significantly reduced in hemin-treated nephritic animals in which proteinuria was also attenuated without a change in monocyte/macrophage infiltration. Hemin (100 to 200 microM) also reduced iNOS protein levels and enzyme activity in cultured mesangial cells stimulated with cytokines. These studies demonstrate that in glomerular immune injury, hemin treatment upregulates glomerular HO-1 with an attendant downregulation of iNOS expression, and thus points to regulatory interaction between the two systems. The beneficial effect of hemin treatment on proteinuria could be linked to downregulation of iNOS.

Effect of thromboxane A2 inhibition and antagonism on prostaglandin and leukotriene synthesis in glomerular immune injury.

In glomerulonephritis there is co-activation of the arachidonic acid cyclooxygenase pathway toward synthesis of prostaglandins (PG) and thromboxane (Tx) and of lipoxypenase pathways toward synthesis of hydroxyeicosatetraenoic acids (HETEs) and leukotrienes (LTs). Cyclooxygenase inhibition with non-steroidal anti-inflammatory drugs results in enhanced glomerular LT synthesis with potentially adverse effects on the severity of the inflammation. The effect of Tx inhibition or antagonism on LT synthesis is unknown. Because TxA2 is the most abundant eicosanoid synthesized in nephritic glomeruli, and because TxA2 synthase inhibitors and receptor antagonists are now available for the treatment of glomerulonephritis, it becomes important to address this question. In this study we assessed the effect of a TxA2 synthase inhibitor, Dazmegrel, and a TxA2 receptor antagonist, SQ-29 548, on glomerular PGE2, LTB4, and 12-HETE synthesis in a model of mesangial nephritis induced in the rat by the administration of a monoclonal antibody against the Thy 1.1 antigen of rat mesangial cells. Dazmegrel, in doses sufficient to effectively block glomerular TxA2 synthesis, significantly increased 12-HETE and PGE2 synthesis without an effect on the synthesis of LTB4. SQ-29 548 had no effect on glomerular PGE2, LTB4, or 12-HETE production. Because PGE2 preserves kidney function in glomerulonephritis, and because 12-HETE inhibits 5-lipoxygenase, the enhanced PGE2 and 12-HETE production within nephritic glomeruli after TxA2 synthase inhibition may be a superior anti-inflammatory strategy when compared with TxA2 receptor antagonism.

Enhanced expression of the cytoskeleton-associated proteins paxillin and focal adhesion kinase in glomerular immune injury.

In a rat model of glomerular immune injury induced by antibody against the glomerular basement membrane (GBM), we assessed changes in the levels and in the extent of tyrosine phosphorylation of two cytoskeleton-associated proteins, focal adhesion kinase (FAK) and paxillin. Glomeruli were isolated 2, 7, and 14 days after the administration of a rabbit anti-rat GBM antibody that induced proliferative nephritis and proteinuria. FAK and paxillin levels in glomerular protein lysates were assessed by immunoprecipitation followed by Western blot analysis. Changes in the tyrosine phosphorylation of immunoprecipitated paxillin and FAK were assessed by Western blot analysis with antiphosphotyrosine antibodies. Glomerular levels of FAK and paxillin were increased in nephritic glomeruli as compared with non-nephritic controls at all time points. There was a discordant increase in the tyrosine phosphorylation levels of paxillin and FAK; the increase in the tyrosine phosphorylation of FAK was sustained and peaked on day 7 of immune injury, whereas that of paxillin was short-lived and peaked on day 2 of injury. We propose that these changes in FAK and paxillin expression and tyrosine phosphorylation reflect interactions between glomerular cells and accumulating extracellular matrix proteins in the course of immune injury, or they constitute parts of wider signaling events within the nephritic glomerulus that involve the cytoskeleton.

Retinoic acids inhibit inducible nitric oxide synthase expression in mesangial cells.

BACKGROUND: Nitric oxide (NO) release as a result of cytokine-mediated activation of inducible nitric oxide synthase (iNOS) in mesangial cells can be sustained and lead to oxidative injury in various forms of glomerular inflammation. Inhibition of iNOS expression and/or activity could therefore be an effective anti-inflammatory strategy. The present study was undertaken to explore whether retinoids, which are known to have anti-inflammatory and immuno-modulatory actions, can attenuate cytokine-stimulated iNOS expression and enzyme activity in murine mesangial cells. METHODS: Expression of iNOS was evaluated by NO production (nitrite analysis), protein (Western blot analysis) and mRNA (RT-PCR analysis) levels in mesangial cells stimulated by a combination of lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) in the presence and absence of all-trans-retinoic acid (ATRA) or its active metabolite, 13-cis-retinoic acid (13-cis-RA). Changes in iNOS enzyme activity were assessed by calculating conversion of L-[14C]arginine to L-[14C]citrulline. The levels of transcription factors nuclear factor-kappaB (NF-kappaB) and activated protein-1 (AP-1) in nuclear extracts prepared from mesangial cells stimulated by a combination of LPS and IFN-gamma in the presence and absence of ATRA was assessed by immunoblot analysis. The effect of both retinoids on transforming growth factor-beta1 (TGF-beta1) levels was also assessed by a quantitative enzyme immunoassay method. RESULTS: The combination of LPS/IFN-gamma stimulated NO production, induced iNOS expression (mRNA and protein) and increased iNOS enzyme activity. ATRA and 13-cis-RA dose-dependently attenuated NO production. This effect was most pronounced at ATRA concentration of 10 microM. At this concentration, ATRA attenuated iNOS expression (mRNA and protein levels) and enzyme activity. ATRA also reduced nuclear levels of both subunits (p50 and p65) of NF-kappaB. TGF-beta1 levels in mesangial cells stimulated with LPS/IFN-gamma in presence of ATRA or 13-cis-RA were also reduced indicating that TGF-beta1 did not mediate the suppressive effect of retinoids on iNOS. CONCLUSIONS: Our studies demonstrate that the retinoids ATRA and 13-cis-RA attenuate iNOS expression and activity in cytokine-stimulated murine mesangial cells. These retinoids may emerge as naturally occurring compounds for treatment of inflammatory glomerular diseases.