956 resultados para interleukin-12 receptor


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BACKGROUND Cushing's disease is associated with high morbidity and mortality. Pasireotide, a potential therapy, has a unique, broad somatostatin-receptor-binding profile, with high binding affinity for somatostatin-receptor subtype 5. METHODS In this double-blind, phase 3 study, we randomly assigned 162 adults with Cushing's disease and a urinary free cortisol level of at least 1.5 times the upper limit of the normal range to receive subcutaneous pasireotide at a dose of 600 mu g (82 patients) or 900 mu g (80 patients) twice daily. Patients with urinary free cortisol not exceeding 2 times the upper limit of the normal range and not exceeding the baseline level at month 3 continued to receive their randomly assigned dose; all others received an additional 300 mu g twice daily. The primary end point was a urinary free cortisol level at or below the upper limit of the normal range at month 6 without an increased dose. Open-label treatment continued through month 12. RESULTS Twelve of the 82 patients in the 600-mu g group and 21 of the 80 patients in the 900-mu g group met the primary end point. The median urinary free cortisol level decreased by approximately 50% by month 2 and remained stable in both groups. A normal urinary free cortisol level was achieved more frequently in patients with baseline levels not exceeding 5 times the upper limit of the normal range than in patients with higher baseline levels. Serum and salivary cortisol and plasma corticotropin levels decreased, and clinical signs and symptoms of Cushing's disease diminished. Pasireotide was associated with hyperglycemia-related adverse events in 118 of 162 patients; other adverse events were similar to those associated with other somatostatin analogues. Despite declines in cortisol levels, blood glucose and glycated hemoglobin levels increased soon after treatment initiation and then stabilized; treatment with a glucose- lowering medication was initiated in 74 of 162 patients. CONCLUSIONS The significant decrease in cortisol levels in patients with Cushing's disease who received pasireotide supports its potential use as a targeted treatment for corticotropinsecreting pituitary adenomas. (Funded by Novartis Pharma; ClinicalTrials.gov number, NCT00434148.)

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The 18 kDa translocator protein (TSPO) also known as the peripheral benzodiazepine receptor (PBR), mediates the transportation of cholesterol and anions from the outer to the inner mitochondrial membrane in different cells types. Although recent evidences indicate a potential role for TSPO in the development of inflammatory processes, the mechanisms involved have not been elucidated. The present study investigated the ability of the specific TSPO ligands, the isoquinoline carboxamide PK11195 and benzodiazepine Ro5-4864, on neutrophil recruitment promoted by the N-formylmethionyl-leucyl-phenylalanine peptide (fMLP), an agonist of G-protein coupled receptor (GPCR). Pre-treatment with Ro5-4864 abrograted fMLP-induced leukocyte-endothelial interactions in mesenteric postcapillary venules in vivo. Moreover, in vitro Ro5-4864 treatment prevented fMLP-induced: (i) L-selectin shedding and overexpression of PECAM-1 on the neutrophil cell surface; (ii) neutrophil chemotaxis and (iii) enhancement of intracellular calcium cations (iCa(+2)). Intriguingly, the two latter effects were augmented by cell treatment with PK11195. An allosteric agonist/antagonist relation may be suggested, as the effects of Ro5-4864 on fMLP-stimulated neutrophils were reverted by simultaneous treatment with PK11195. Taken together, these data highlight TSPO as a modulator of pathways of neutrophil adhesion and locomotion induced by GPCR, connecting TSPO actions and the onset of an innate inflammatory response. (C) 2011 Elsevier Inc. All rights reserved.

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We investigated whether interleukin-4 (IL-4) is present and capable of reducing inflammatory changes seen in ifosfamide-induced hemorrhagic cystitis. Male Swiss mice were treated with saline or ifosfamide alone or ifosfamide with the classical protocol with mesna and analyzed by changes in bladder wet weight (BWW), macroscopic and microscopic parameters, exudate, and hemoglobin quantification. In other groups, IL-4 was administered intraperitoneally 1 h before ifosfamide. In other experimental groups, C57BL/6 WT (wild type) and C57BL/6 WT IL-4 (-/-) knockout animals were treated with ifosfamide and analyzed for changes in BWW. Quantification of bladder IL-4 protein by ELISA in control, ifosfamide-, and mesna-treated groups was performed. Immunohistochemistry to tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) as well as protein identification by Western blot assay for inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was carried out on ifosfamide- and IL-4-treated animals. In other experimental groups, antiserum against IL-4 was given 30 min before ifosfamide. In IL-4-treated animals, the severity of hemorrhagic cystitis was significantly milder than in animals treated with ifosfamide only, an effect that was reverted with serum anti-IL-4. Moreover, knockout animals for IL-4 (-/-) exhibit a worse degree of inflammation when compared to C57BL/6 wild type. Exogenous IL-4 also attenuated TNF-alpha, IL-1 beta, iNOS, and COX-2 expressions in ifosfamide-treated bladders. IL-4, an anti-inflammatory cytokine, attenuates the inflammation seen in ifosfamide-induced hemorrhagic cystitis.

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Thiazolidinediones (TZDs) act through peroxisome proliferator activated receptor (PPAR) gamma to increase insulin sensitivity in type 2 diabetes (T2DM), but deleterious effects of these ligands mean that selective modulators with improved clinical profiles are needed. We obtained a crystal structure of PPAR gamma ligand binding domain (LBD) and found that the ligand binding pocket (LBP) is occupied by bacterial medium chain fatty acids (MCFAs). We verified that MCFAs (C8-C10) bind the PPAR gamma LBD in vitro and showed that they are low-potency partial agonists that display assay-specific actions relative to TZDs; they act as very weak partial agonists in transfections with PPAR gamma LBD, stronger partial agonists with full length PPAR gamma and exhibit full blockade of PPAR gamma phosphorylation by cyclin-dependent kinase 5 (cdk5), linked to reversal of adipose tissue insulin resistance. MCFAs that bind PPAR gamma also antagonize TZD-dependent adipogenesis in vitro. X-ray structure B-factor analysis and molecular dynamics (MD) simulations suggest that MCFAs weakly stabilize C-terminal activation helix (H) 12 relative to TZDs and this effect is highly dependent on chain length. By contrast, MCFAs preferentially stabilize the H2-H3/beta-sheet region and the helix (H) 11-H12 loop relative to TZDs and we propose that MCFA assay-specific actions are linked to their unique binding mode and suggest that it may be possible to identify selective PPAR gamma modulators with useful clinical profiles among natural products.

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The recent discovery that peroxisome proliferator-activated receptor gamma (PPAR gamma) targeted anti-diabetic drugs function by inhibiting Cdk5-mediated phosphorylation of the receptor has provided a new viewpoint to evaluate and perhaps develop improved insulin-sensitizing agents. Herein we report the development of a novel thiazolidinedione that retains similar anti-diabetic efficacy as rosiglitazone in mice yet does not elicit weight gain or edema, common side effects associated with full PPAR gamma activation. Further characterization of this compound shows GQ-16 to be an effective inhibitor of Cdk5-mediated phosphorylation of PPAR gamma. The structure of GQ-16 bound to PPAR gamma demonstrates that the compound utilizes a binding mode distinct from other reported PPAR gamma ligands, although it does share some structural features with other partial agonists, such as MRL-24 and PA-082, that have similarly been reported to dissociate insulin sensitization from weight gain. Hydrogen/deuterium exchange studies reveal that GQ-16 strongly stabilizes the beta-sheet region of the receptor, presumably explaining the compound's efficacy in inhibiting Cdk5-mediated phosphorylation of Ser-273. Molecular dynamics simulations suggest that the partial agonist activity of GQ-16 results from the compound's weak ability to stabilize helix 12 in its active conformation. Our results suggest that the emerging model, whereby "ideal" PPAR gamma-based therapeutics stabilize the beta-sheet/Ser-273 region and inhibit Cdk5-mediated phosphorylation while minimally invoking adipogenesis and classical agonism, is indeed a valid framework to develop improved PPAR gamma modulators that retain antidiabetic actions while minimizing untoward effects.

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Objective: Some previous studies have shown that gingipains, trypsin-like proteases produced by Porphyromonas gingivalis, up-regulate human beta defensin-2 (HBD-2) mRNA expression through protease-activated receptor-2 (PAR(2)) in gingival epithelial cells. This study aimed at investigating salivary HBD-2 levels and crevicular PAR(2) mRNA expression in human chronic periodontitis and evaluating whether periodontal treatment affected this process. Methods: Salivary and gingival crevicular fluid (GCF) samples were collected from periodontally healthy (control) and chronic periodontitis patients at baseline and 50 days after nonsurgical periodontal treatment. Salivary HBD-2, and GCF TNF-alpha levels were analysed by ELISA, and PAR(2) mRNA at the GCF was evaluated by RT-PCR. Results: P. gingivalis was significantly (p < 0.05) more prevalent in patients with chronic periodontitis when compared to controls. This prevalence decreased after periodontal therapy (p < 0.0001). The control group showed statistically significant lower levels of HBD-2, TNF-alpha, and PAR(2) expression when compared to the chronic periodontitis group. In addition, periodontal treatment significantly reduced PAR(2) expression and HBD-2 levels in chronic periodontitis patients (p < 0.001). Conclusions: Our results suggest that salivary HBD-2 levels and PAR(2) mRNA expression from GCF are higher in subjects with chronic periodontitis than in healthy subjects, and that periodontal treatment decreases both HBD-2 levels and PAR(2) expression. (C) 2012 Elsevier Ltd. All rights reserved.

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Evidences have suggested that the endocannabinoid system is overactive in obesity, resulting in enhanced endocannabinoid levels in both circulation and visceral adipose tissue. The blockade of cannabinoid receptor type 1 (CB1) has been proposed for the treatment of obesity. Besides loss of body weight, CB1 antagonism improves insulin sensitivity, in which the glucose transporter type 4 (GLUT4) plays a key role. The aim of this study was to investigate the modulation of GLUT4-encoded gene (Slc2a4 gene) expression by CB1 receptor. For this, 3T3-L1 adipocytes were incubated in the presence of a highly selective CB1 receptor agonist (1 mu M arachidonyl-2'-chloroethylamide) and/or a CB1 receptor antagonist/inverse agonist (0.1, 0.5, or 1 mu M AM251, 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide). After acute (2 and 4 h) and chronic (24 h) treatments, cells were harvested to evaluate: i) Slc2a4, Cnr1 (CB1 receptor-encoded gene), and Srebf1 type a (SREBP-1a type-encoded gene) mRNAs (real-time PCR); ii) GLUT4 protein (western blotting); and iii) binding activity of nuclear factor (NF)-kappa B and sterol regulatory element-binding protein (SREBP)-1 specifically in the promoter of Slc2a4 gene (electrophoretic mobility shift assay). Results revealed that both acute and chronic CB1 receptor antagonism greatly increased (similar to 2.5-fold) Slc2a4 mRNA and protein content. Additionally, CB1-induced upregulation of Slc2a4 was accompanied by decreased binding activity of NF-kappa B at 2 and 24 h, and by increased binding activity of the SREBP-1 at 24 h. In conclusion, these findings reveal that the blockade of CB1 receptor markedly increases Slc2a4/GLUT4 expression in adipocytes, a feature that involves NF-kappa B and SREBP-1 transcriptional regulation. Journal of Molecular Endocrinology (2012) 49, 97-106

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The peroxisome proliferator-activated receptor gamma (PPAR gamma) is a target for treatment of type II diabetes and other conditions. PPAR gamma full agonists, such as thiazolidinediones (TZDs), are effective insulin sensitizers and anti-inflammatory agents, but their use is limited by adverse side effects. Luteolin is a flavonoid with anti-inflammatory actions that binds PPAR gamma but, unlike TZDs, does not promote adipocyte differentiation. However, previous reports suggested variously that luteolin is a PPAR gamma agonist or an antagonist. We show that luteolin exhibits weak partial agonist/antagonist activity in transfections, inhibits several PPAR gamma target genes in 3T3-L1 cells (LPL, ORL1, and CEBP alpha) and PPAR gamma-dependent adipogenesis, but activates GLUT4 to a similar degree as rosiglitazone, implying gene-specific partial agonism. The crystal structure of the PPAR gamma ligand-binding domain (LBD) reveals that luteolin occupies a buried ligand-binding pocket (LBP) but binds an inactive PPAR gamma LBD conformer and occupies a space near the beta-sheet region far from the activation helix (H12), consistent with partial agonist/antagonist actions. A single myristic acid molecule simultaneously binds the LBP, suggesting that luteolin may cooperate with other ligands to bind PPAR gamma, and molecular dynamics simulations show that luteolin and myristic acid cooperate to stabilize the Omega-loop among H2', H3, and the beta-sheet region. It is noteworthy that luteolin strongly suppresses hypertonicity-induced release of the pro-inflammatory interleukin-8 from human corneal epithelial cells and reverses reductions in transepithelial electrical resistance. This effect is PPAR gamma-dependent. We propose that activities of luteolin are related to its singular binding mode, that anti-inflammatory activity does not require H12 stabilization, and that our structure can be useful in developing safe selective PPAR gamma modulators.

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Hypertension is the most common medical disorder in pregnancy, and a leading cause of maternal and neonatal morbidity and mortality. Vitamin D endocrine system has important influence on immune modulation and endothelial function, which play a role in preeclampsia (PE) and gestational hypertension (GH). Vitamin D receptor (VDR) is present in a large variety of cell types, including placental cells. We examined whether there is an association between VDR polymorphisms (FokI, ApaI and BsmI) with PE or with GH. Restriction fragment length polymorphism techniques were used to genotype 529 pregnant (154 with GH, 162 with PE, and 213 healthy pregnant-HP). VDR haplotype frequencies were inferred using the PHASE 2.1 program. We found similar genotype distributions for the three VDR polymorphisms in both PE and GH groups compared with the HP group (all P > 0.05). In parallel with these findings, the VDR haplotype frequency distribution was similar in both PE and GH groups compared with the HP group (all P > 0.05). Our results showing no significant association between VDR polymorphisms or haplotypes with PE or GH suggest that genetic variations in VDR do not predispose to hypertensive disorders of pregnancy.

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Background: Despite advances in supportive care, sepsis-related mortality remains high, especially in patients with acute kidney injury (AKI). Erythropoietin can protect organs against ischemia and sepsis. This effect has been linked to activation of intracellular survival pathways, although the mechanism remains unclear. Continuous erythropoietin receptor activator (CERA) is an erythropoietin with a unique pharmacologic profile and long half-life. We hypothesized that pretreatment with CERA would be renoprotective in the cecal ligation and puncture (CLP) model of sepsis-induced AKI. Methods: Rats were randomized into three groups: control; CLP; and CLP+CERA (5 mu g/kg body weight, i.p. administered 24 h before CLP). At 24 hours after CLP, we measured creatinine clearance, biochemical variables, and hemodynamic parameters. In kidney tissue, we performed immunoblotting-to quantify expression of the Na-K-2Cl cotransporter (NKCC2), aquaporin 2 (AQP2), Toll-like receptor 4 (TLR4), erythropoietin receptor (EpoR), and nuclear factor kappa B (NF-kappa B)-and immunohistochemical staining for CD68 (macrophage infiltration). Plasma interleukin (IL)-2, IL-1 beta, IL-6, IL-10, interferon gamma, and tumor necrosis factor alpha were measured by multiplex detection. Results: Pretreatment with CERA preserved creatinine clearance and tubular function, as well as the expression of NKCC2 and AQP2. In addition, CERA maintained plasma lactate at normal levels, as well as preserving plasma levels of transaminases and lactate dehydrogenase. Renal expression of TLR4 and NF-kappa B was lower in CLP+CERA rats than in CLP rats (p<0.05 and p<0.01, respectively), as were CD68-positive cell counts (p<0.01), whereas renal EpoR expression was higher (p<0.05). Plasma levels of all measured cytokines were lower in CLP+CERA rats than in CLP rats. Conclusion: CERA protects against sepsis-induced AKI. This protective effect is, in part, attributable to suppression of the inflammatory response.

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Under many circumstances, the host constituents that are found in the tumor microenvironment support a malignancy network and provide the cancer cells with advantages in proliferation, invasiveness and metastasis establishment at remote organs. It is known that Toll like receptors (TLRs) are expressed not only on immune cells but also on cancer cells and it has suggested a deleterious role for TLR3 in inflammatory disease. Hypothesizing that altered IFN gamma signaling may be a key mechanism of immune dysfunction common to cancer as well CXCR4 is overexpressed among breast cancer patients, the mRNA expression of TLR3, CXCR4 and IFN gamma in breast cancer tumor tissues was investigated. No statistically significant differences in the expression of CXCR4 mRNA, IFN gamma and TLR3 between healthy and tumor tissues was observed, however, it was verified a positive correlation between mRNA relative expression of TLR3 and CXCR4 (p < 0.001), and mRNA relative expression of TLR3 was significantly increased in breast cancer tumor tissue when compared to healthy mammary gland tissue among patients expressing high IFN gamma (p = 0.001). Since the tumor microenvironment plays important roles in cancer initiation, growth, progression, invasion and metastasis, it is possible to propose that an overexpression of IFN gamma mRNA due to the pro-inflammatory microenvironment can lead to an up-regulation of CXCR4 mRNA and consequently to an increased TLR3 mRNA expression even among nodal negative patients. In the future, a comprehensive study of TLR3, CXCR4 and IFN gamma axis in primary breast tumors and corresponding healthy tissues will be crucial to further understanding of the cancer network.

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Adiponectin and interleukin 10 (IL-10) are adipokines that are predominantly secreted by differentiated adipocytes and are involved in energy homeostasis, insulin sensitivity, and the anti-inflammatory response. These two adipokines are reduced in obese subjects, which favors increased activation of nuclear factor kappa B (NF-kappa B) and leads to elevation of pro-inflammatory adipokines. However, the effects of adiponectin and IL-10 on NF-kappa B DNA binding activity (NF-kappa Bp50 and NF-kappa Bp65) and proteins involved with the toll-like receptor (TLR-2 and TLR-4) pathway, such as MYD88 and TRAF6 expression, in lipopolysaccharide-treated 3T3-L1 adipocytes are unknown. Stimulation of lipopolysaccharide-treated 3T3-L1 adipocytes for 24 h elevated IL-6 levels; activated the NF-kappa B pathway cascade; increased protein expression of IL-6R, TLR-4, MYD88, and TRAF6; and increased the nuclear activity of NF-kappa B (p50 and p65) DNA binding. Adiponectin and IL-10 inhibited the elevation of IL-6 levels and activated NF-kappa B (p50 and p65) DNA binding. Taken together, the present results provide evidence that adiponectin and IL-10 have an important role in the anti-inflammatory response in adipocytes. In addition, inhibition of NF-kappa B signaling pathways may be an excellent strategy for the treatment of inflammation in obese individuals. (C) 2011 Elsevier Ltd. All rights reserved.

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Acute lung injury is an inflammatory condition for which treatment is mainly supportive because effective therapies have not been developed. Cannabidiol, a non-psychotropic cannabinoid component of marijuana (Cannabis sativa), has potent immunosuppressive and anti-inflammatory properties. Therefore, we investigated the possible anti-inflammatory effect of cannabidiol in a murine model of acute lung injury. Analysis of total inflammatory cells and differential in bronchoalveolar lavage fluid was used to characterize leukocyte migration into the lungs; myeloperoxidase activity of lung tissue and albumin concentration in the bronchoalveolar lavage fluid were analyzed by colorimetric assays; cytokine/chemokine production in the bronchoalveolar lavage fluid was also analyzed by Cytometric Bead Arrays and Enzyme-Linked Immunosorbent Assay (ELISA). A single dose of cannabidiol (20 mg/kg) administered prior to the induction of LPS (lipopolysaccharide)-induced acute lung injury decreases leukocyte (specifically neutrophil) migration into the lungs, albumin concentration in the bronchoalveolar lavage fluid, myeloperoxidase activity in the lung tissue, and production of pro-inflammatory cytokines (TNF and IL-6) and chemokines (MCP-1 and MIP-2) 1, 2, and 4 days after the induction of LPS-induced acute lung injury. Additionally, adenosine A(2A) receptor is involved in the anti-inflammatory effects of cannabidiol on LPS-induced acute lung injury because ZM241385 (4-(2[7-Amino-2-(2-furyl)[1,2,4] triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl) phenol) (a highly selective antagonist of adenosine A(2A) receptor) abrogated all of the anti-inflammatory effects of cannabidiol previously described. Thus, we show that cannabidiol has anti-inflammatory effects in a murine model of acute lung injury and that this effect is most likely associated with an increase in the extracellular adenosine offer and signaling through adenosine A(2A) receptor. (C) 2012 Elsevier B. V. All rights reserved.

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Abstract Background Preconception allergen immunization prevents neonatal allergen sensitization in mice by a complex interaction between regulatory cells/factors and antibodies. The present study assessed the influence of maternal immunization with ovalbumin (OVA) on the immune response of 3 day-old and 3 week-old offspring immunized or non-immunized with OVA and evaluated the effect of IgG treatment during fetal development or neonatal period. Results Maternal immunization with OVA showed increased levels of FcγRIIb expression in splenic B cells of neonates, which were maintained for up to 3 weeks and not affected by additional postnatal OVA immunization. Maternal immunization also exerted a down-modulatory effect on both IL-4 and IFN-γ-secreting T cells and IL-4 and IL-12- secreting B cells. Furthermore, immunized neonates from immunized mothers showed a marked inhibition of antigen-specifc IgE Ab production and lowered Th2/Th1 cytokine levels, whereas displaying enhanced FcγRIIb expression on B cells. These offspring also showed reduced antigen-specific proliferative response and lowered B cell responsiveness. Moreover, in vitro evaluation revealed an impairment of B cell activation upon engagement of B cell antigen receptor by IgG from OVA-immunized mice. Finally, in vivo IgG transference during pregnancy or breastfeeding revealed that maternal Ab transference was able to increase regulatory cytokines, such as IL-10, in the prenatal stage; yet only the postnatal treatment prevented neonatal sensitization. None of the IgG treatments induced immunological changes in the offspring, as it was observed for those from OVA-immunized mothers. Conclusion Maternal immunization upregulates the inhibitory FcγRIIb expression on offspring B cells, avoiding skewed Th2 response and development of allergy. These findings contribute to the advancement of prophylactic strategies to prevent allergic diseases in early life.

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Abstract Background The expression of glucocorticoid-receptor (GR) seems to be a key mechanism in the regulation of glucocorticoid (GC) sensitivity and is potentially involved in cases of GC resistance or hypersensitivity. The aim of this study is to describe a method for quantitation of GR alpha isoform (GRα) expression using real-time PCR (qrt-PCR) with analytical capabilities to monitor patients, offering standard-curve reproducibility as well as intra- and inter-assay precision. Results Standard-curves were constructed by employing standardized Jurkat cell culture procedures, both for GRα and BCR (breakpoint cluster region), as a normalizing gene. We evaluated standard-curves using five different sets of cell culture passages, RNA extraction, reverse transcription, and qrt-PCR quantification. Intra-assay precision was evaluated using 12 replicates of each gene, for 2 patients, in a single experiment. Inter-assay precision was evaluated on 8 experiments, using duplicate tests of each gene for two patients. Standard-curves were reproducible, with CV (coefficient of variation) of less than 11%, and Pearson correlation coefficients above 0,990 for most comparisons. Intra-assay and inter-assay were 2% and 7%, respectively. Conclusion This is the first method for quantitation of GRα expression with technical characteristics that permit patient monitoring, in a fast, simple and robust way.