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Background: Eosinophils appear to contribute to the efficacy of immunotherapy and their frequency was suggested as a predictive biomarker. Whether this observation could be transferred to patients treated with targeted therapy remains unknown. Methods: Blood and serum samples of healthy controls and 216 patients with advanced melanoma were prospectively and retrospectively collected. Freshly isolated eosinophils were phenotypically characterized by flow cytometry and co-cultured in vitro with melanoma cells to assess cytotoxicity. Soluble serum markers and peripheral blood counts were used for correlative studies. Results: Eosinophil-mediated cytotoxicity towards melanoma cells, as well as phenotypic characteristics, were similar when comparing healthy donors and patients. However, high relative pre-treatment eosinophil counts were significantly associated with response to MAPKi (p = 0.013). Eosinophil-mediated cytotoxicity towards melanoma cells is dose-dependent and requires proximity of eosinophils and their target in vitro. Treatment with targeted therapy in the presence of eosinophils results in an additive tumoricidal effect. Additionally, melanoma cells affected eosinophil phenotype upon co-culture. Conclusion: High pre-treatment eosinophil counts in advanced melanoma patients were associated with a significantly improved response to MAPKi. Functionally, eosinophils show potent cytotoxicity towards melanoma cells, which can be reinforced by MAPKi. Further studies are needed to unravel the molecular mechanisms of our observations.
Context
Cushing’s syndrome (CS) is a rare disease of endogenous hypercortisolism associated with high morbidity and mortality. Diagnosis and classification of CS is still challenging.
Objective
Circulating microRNAs (miRNAs) are minimally invasive diagnostic markers. Our aim was to characterize the circulating miRNA profiles of CS patients and to identify distinct profiles between the two major CS subtypes.
Methods
We included three groups of patients from the German Cushing’s registry: ACTH-independent CS (Cortisol-Producing-Adenoma; CPA), ACTH-dependent pituitary CS (Cushing’s Disease; CD), and patients in whom CS had been ruled out (controls). Profiling of miRNAs was performed by next-generation-sequencing (NGS) in serum samples of 15 CS patients (each before and after curative surgery) and 10 controls. Significant miRNAs were first validated by qPCR in the discovery cohort and then in an independent validation cohort of 20 CS patients and 11 controls.
Results
NGS identified 411 circulating miRNAs. Differential expression of 14 miRNAs were found in the pre- and postoperative groups. qPCR in the discovery cohort validated 5 of the significant miRNAs from the preoperative group analyses. Only, miR-182-5p was found to be significantly upregulated in the CD group of the validation cohort. Comparing all CS samples as a group with the controls did not reveal any significant differences in expression.
Outcome
In conclusion, our study identified miR-182-5p as a possible biomarker for CD, which has to be validated in a prospective cohort. Furthermore, our results suggest that presence or absence of ACTH might be at least as relevant for miRNA expression as hypercortisolism itself.
Conjugation of reactive intermediates of drugs with proteins or DNA may result in toxic effects such as hepatotoxicity, agranulocytosis, allergies, tumors, etc. From 1975 to 1999, 2.9% of drugs were withdrawn from the market due to such severe adverse drug reactions. Thus, formation of chemically reactive intermediates is a widely discussed problem in drug development processes. Early detection of potentially toxic compounds is required for drug discovery and drug development. Conjugation of such electrophilic compounds with glutathione (GSH) is one of the most important detoxifying reactions in vivo. Processing of these GSH-conjugates ultimately leads to the formation of renally cleared mercapturic acids, which may also be oxidized to sulfoxides. Thus, mercapturic acids may be generated and detected in vitro and non-invasively in vivo in urine to assess the reactivity of a compound in early stages of drug development processes. Therefore, the aim of this work was to develop and evaluate a HPLC-MS/MS screening method for simple and rapid detection and characterization of known and unknown mercapturic acids and application of the method to several different matrices. Based on the common constant neutral loss (CNL) of 129 Da of all mercapturic acids tested (in negative ion mode), a CNL survey scan was performed using a linear ion trap instrument and was combined with two enhanced product ion (EPI) scans with different collision energies to characterize the detected signals. The CNL resulted from the cleavage between the sulfur and the carbon atom in the N-acetyl-L-cysteine moiety. After optimization of the experimental parameters, the detection limits of the reference substances in rat urine ranged from 0.3 to 15.5 pmol on column (i.e. 20 ng/ml to 800 ng/ml). For in vitro evaluation of the method, the model compounds acetaminophen, diclofenac, bifonazole, clozapine, troglitazone, carbamazepine, and bisphenol A were screened for formation of reactive intermediates and, hence, detection of the corresponding mercapturic acids. To determine possible species- and tissue-specific toxicities, the model compounds were incubated with stimulated neutrophils and with liver microsomes from rats and humans. Species-specific differences were observed in incubations of acetaminophen and diclofenac with rat and human hepatic microsomes. Tissue-specific differences in biotransformation of the model compounds in incubations with human neutrophils and human liver microsomes were observed for diclofenac, carbamazepine, clozapine, and bifonazole. The developed HPLC-MS/MS method was also evaluated in vivo by analysis of rat and human urine. Drug-related mercapturic acids were detected in urine of rats orally treated with acetaminophen (20 mg/kg and 640 mg/kg b.w.) or diclofenac (10 mg/kg and 20 mg/kg b.w.). Human urine samples were analyzed before and after oral administration of a clinically used dose of 500 mg and 50 mg of acetaminophen. Besides detection of the mercapturic acid of N-acetylbenzoquinoneimine (AAP-MA), a second mercapturic acid with m/z 327 occurred dose-dependently in rat and human urine samples after administration of acetaminophen. Further investigations on identification of this metabolite using authentic compounds and comparing their MS/MS mass spectra demonstrated oxidation of AAP-MA to stereoisomeric sulfoxides in vivo. For diclofenac, a novel mercapturic acid with m/z 441 was detected in rat urine samples that was identical to a metabolite obtained in incubations with human neutrophils before. The in vivo formation of this diclofenac metabolite is described here for the first time. In addition, three endogenously formed mercapturic acids were detected and identified. In conclusion, the results of the in vitro and in vivo evaluation demonstrate the advantages of the rapid and generic HPLC-MS/MS screening method for the detection of mercapturic acids, that can be obtained with a minimum of sample preparation and a high throughput in diverse matrices.
High-Sensitivity Troponin: A Clinical Blood Biomarker for Staging Cardiomyopathy in Fabry Disease
(2016)
Background
High‐sensitivity troponin (hs‐TNT), a biomarker of myocardial damage, might be useful for assessing fibrosis in Fabry cardiomyopathy. We performed a prospective analysis of hs‐TNT as a biomarker for myocardial changes in Fabry patients and a retrospective longitudinal follow‐up study to assess longitudinal hs‐TNT changes relative to fibrosis and cardiomyopathy progression.
Methods and Results
For the prospective analysis, hs‐TNT from 75 consecutive patients with genetically confirmed Fabry disease was analyzed relative to typical Fabry‐associated echocardiographic findings and total myocardial fibrosis as measured by late gadolinium enhancement (LE) on magnetic resonance imaging. Longitudinal data (3.9±2.0 years), including hs‐TNT, LE, and echocardiographic findings from 58 Fabry patients, were retrospectively collected. Hs‐TNT level positively correlated with LE (linear correlation coefficient, 0.72; odds ratio, 32.81 [95% CI, 3.56–302.59]; P=0.002); patients with elevated baseline hs‐TNT (>14 ng/L) showed significantly increased LE (median: baseline, 1.9 [1.1–3.3] %; follow‐up, 3.2 [2.3–4.9] %; P<0.001) and slightly elevated hs‐TNT (baseline, 44.7 [30.1–65.3] ng/L; follow‐up, 49.1 [27.6–69.5] ng/L; P=0.116) during follow‐up. Left ventricular wall thickness and EF of patients with elevated hs‐TNT were decreased during follow‐up, indicating potential cardiomyopathy progression.
Conclusions
hs‐TNT is an accurate, easily accessible clinical blood biomarker for detecting replacement fibrosis in patients with Fabry disease and a qualified predictor of cardiomyopathy progression. Thus, hs‐TNT could be helpful for staging and follow‐up of Fabry patients.
The gene encoding the LIM and SH3 domain protein (LASP1) was cloned two decades ago from a cDNA library of breast cancer metastases. As the first protein of a class comprising one N-terminal LIM and one C-terminal SH3 domain, LASP1 founded a new LIM-protein subfamily of the nebulin group. Since its discovery LASP1 proved to be an extremely versatile protein because of its exceptional structure allowing interaction with various binding partners, its ubiquitous expression in normal tissues, albeit with distinct expression patterns, and its ability to transmit signals from the cytoplasm into the nucleus. As a result, LASP1 plays key roles in cell structure, physiological processes, and cell signaling. Furthermore, LASP1 overexpression contributes to cancer aggressiveness hinting to a potential value of LASP1 as a cancer biomarker. In this review we summarize published data on structure, regulation, function, and expression pattern of LASP1, with a focus on its role in human cancer and as a biomarker protein. In addition, we provide a comprehensive transcriptome analysis of published microarrays (n=2,780) that illustrates the expression profile of LASP1 in normal tissues and its overexpression in a broad range of human cancer entities.
We have previously identified serum miR-483-5p as a preoperative diagnosis and prognosis biomarker for adrenocortical cancer (ACC). Here, we aimed to determine whether circulating miR-483-5p levels measured 3 months post-operatively distinguished patients with good prognosis (no recurrence for at least 3 years; NR3yrs) from patients with poor prognosis (recurrence or death within 3 years after surgery; R < 3yrs). We conducted a single-center retrospective analysis using sera from 48 patients with ACC that were initially non-metastatic and treated by surgery. Sera sampled within 3 months after surgery were available in 26 patients. MiR-483-5p absolute circulating levels were measured using quantitative PCR. Thirteen patients showed a recurrence before 3 years (=R < 3yrs). Thirteen patients showed no recurrence within 3 years, including 11 patients with a follow-up longer than 3 years (=NR3yrs). Serum miR-483-5p levels were higher in R < 3yrs than in NR3yrs: 1,541,990 ± 428,377 copies/mL vs. 388,457 ± 62,169 copies/mL (p = 0.002). Receiver operating characteristic analysis showed that a value of 752,898 copies/mL distinguished R < 3yrs from NR3yrs with 61.5% sensitivity (CI 31.6–86.1) and 100% specificity (CI 71.5–100) with an area under the curve of 0.853. Patients with a value below this threshold had a significantly longer recurrence-free and overall survival. In multivariate analysis, miR-483-5p provided the single best prognostic value for recurrence-free survival (RFS) (hazard ratio (HR) for recurrence 5.98, p < 0.011) but not for overall survival. Our study suggests that serum miR-483-5p is a potent early post-operative biomarker for ACC prognosis that might be a better predictor of RFS than currently used markers.
Major depressive disorder (MDD) is a very common stress-related mental disorder that carries a huge burden for affected patients and the society. It is associated with a high mortality that derives from suicidality and the development of serious medical conditions such as heart diseases, diabetes, and stroke. Although a range of effective antidepressants are available, more than 50% of the patients do not respond to the first treatment they are prescribed and around 30% fail to respond even after several treatment attempts. The heterogeneous condition of MDD, the lack of biomarkers matching patients with the right treatments and the situation that almost all available drugs are only targeting the serotonin, norepinephrine, or dopamine signaling, without regulating other potentially dysregulated systems may explain the insufficient treatment status. The hypothalamic-pituitary-adrenal (HPA) axis is one of these other systems, there is numerous and robust evidence that it is implicated in MDD and other stress-related conditions, but up to date there is no specific drug targeting HPA axis components that is approved and no test that is routinely used in the clinical setting identifying patients for such a specific treatment. Is there still hope after these many years for a breakthrough of agents targeting the HPA axis? This review will cover tests detecting altered HPA axis function and the specific treatment options such as glucocorticoid receptor (GR) antagonists, corticotropin-releasing hormone 1 (CRH1) receptor antagonists, tryptophan 2,3-dioxygenase (TDO) inhibitors and FK506 binding protein 5 (FKBP5) receptor antagonists.
Deeper understanding of mold-induced cytokine signatures could promote advances in the diagnosis and treatment of invasive mycoses and mold-associated hypersensitivity syndromes. Currently, most T-cellular immunoassays in medical mycology require the isolation of mononuclear cells and have limited robustness and practicability, hampering their broader applicability in clinical practice. Therefore, we developed a simple, cost-efficient whole blood (WB) assay with dual α-CD28 and α-CD49d co-stimulation to quantify cytokine secretion in response to Aspergillus fumigatus antigens. Dual co-stimulation strongly enhanced A. fumigatus-induced release of T-cellular signature cytokines detectable by enzyme-linked immunosorbent assay (ELISA) or a multiplex cytokine assay. Furthermore, T-cell-dependent activation and cytokine response of innate immune cells was captured by the assay. The protocol consistently showed little technical variation and high robustness to pre-analytic delays of up to 8 h. Stimulation with an A. fumigatus lysate elicited at least 7-fold greater median concentrations of key T-helper cell signature cytokines, including IL-17 and the type 2 T-helper cell cytokines IL-4 and IL-5 in WB samples from patients with Aspergillus-associated lung pathologies versus patients with non-mold-related lung diseases, suggesting high discriminatory power of the assay. These results position WB-ELISA with dual co-stimulation as a simple, accurate, and robust immunoassay for translational applications, encouraging further evaluation as a platform to monitor host immunity to opportunistic pathogens.
Occupational mold exposure can lead to Aspergillus-associated allergic diseases including asthma and hypersensitivity pneumonitis. Elevated IL-17 levels or disbalanced T-helper (Th) cell expansion were previously linked to Aspergillus-associated allergic diseases, whereas alterations to the Th cell repertoire in healthy occupationally exposed subjects are scarcely studied. Therefore, we employed functional immunoassays to compare Th cell responses to A. fumigatus antigens in organic farmers, a cohort frequently exposed to environmental molds, and non-occupationally exposed controls. Organic farmers harbored significantly higher A. fumigatus-specific Th-cell frequencies than controls, with comparable expansion of Th1- and Th2-cell frequencies but only slightly elevated Th17-cell frequencies. Accordingly, Aspergillus antigen-induced Th1 and Th2 cytokine levels were strongly elevated, whereas induction of IL-17A was minimal. Additionally, increased levels of some innate immune cell-derived cytokines were found in samples from organic farmers. Antigen-induced cytokine release combined with Aspergillus-specific Th-cell frequencies resulted in high classification accuracy between organic farmers and controls. Aspf22, CatB, and CipC elicited the strongest differences in Th1 and Th2 responses between the two cohorts, suggesting these antigens as potential candidates for future bio-effect monitoring approaches. Overall, we found that occupationally exposed agricultural workers display a largely balanced co-expansion of Th1 and Th2 immunity with only minor changes in Th17 responses.
Lewy bodies and Lewy neurites are neuropathological hallmarks of Parkinson’s disease (PD). These depositions in the brain mostly consist of aggregated α-synuclein (α-syn) phosphorylated at Ser129. A number of studies reported detection of phosphorylated α-syn (p-α-syn) in the dermal nerve fibers in Parkinson’s disease. The objective of this study was to investigate whether pathological α-syn accumulations detected in the skin represent aggregated protein. A number of methods aimed at detecting α-syn oligomers and aggregates were first tested and optimized on the brain samples in PD and normal control. These methods included proximity ligation assay (PLA), PET-blot, immunohistochemical (IHC) stains with α-syn aggregate (5G4) or oligomer specific (ASyO5) antibodies and a stain against native α-syn (syn211) after proteinase K (PK) digestion. Subsequently, the most specific methods (stains with 5G4, ASyO5 and syn211 after PK digestion) were studied in two separate patient and control cohorts. Anti-p-α-syn stain was performed in parallel.
Single sections from at least 2 biopsy sites from 44 patients and 22 controls (cohort 1) as well as serial sections of 4 biopsy sites from 27 patients and 5 controls (cohort 2) were systematically studied for presence of aggregated and oligomeric α-syn. In total, 5G4 positive deposits were found in 24% (cohort 1) and 37% (cohort 2), ASyO5 positive lesions in 17,7% (cohort 1) and 33% (cohort 2), syn211 positive lesions after PK digestion in 38,7% (cohort 1) and 48% (cohort 2) of cases. There was a major overlap among positivity for a particular staining on the patient level and in most cases, the same nerve fiber was found to be positive for all 4 markers in neighboring sections. Among the skin biopsies which contained p-α-syn accumulation, 59% were also PK resistant, 41% were 5G4 positive and 45% were ASyO5 positive. The samples belonging to normal controls did not show any positive signal in either of the newly established stainings or in the anti-p-α-syn staining.
Using 3 distinct IHC methods, α-syn oligomers and aggregates were detectable in the majority of p-α-syn positive skin biopsies. This finding supports the hypothesis that α-syn aggregation occurs in the peripheral (i.e. dermal) nerves and can be specifically detected using skin biopsy.