Milena Ugrin

Expression of TLR7 , TLR9 , JAK2 , and STAT3 genes in peripheral blood mononuclear cells from patients with systemic sclerosis

Systemic sclerosis (SSc) is a rare, chronic, multisystem autoimmune disease clinically characterized by progressive fibrosis of the skin and internal organs. The basic mechanism appears to involve endothelial cell injury, overproduction of extracellular matrix proteins, and aberrant immune activation. So far, there have been a few attempts to find genetic biomarkers for monitoring disease activity or for correlation with certain symptoms. In order to reveal reliable biomarkers, we analyzed the expression of four genes representing three important signaling pathways, TLR7, TLR9, and JAK2-STAT3. Using RT-qPCR technique, we analyzed the expression of TLR7, TLR9, JAK2, and STAT3 genes in peripheral blood mononuclear cells of 50 SSc patients and 13 healthy individuals. We detected significant upregulation of TLR7 gene expression in a group of SSc patients compared to non-SSc group. Receiver operating characteristic (ROC) analysis showed that TLR7 expression efficiently discriminates SSc cases from healthy individuals. High TLR7 expression positively correlated with the late form of disease, active SSc, and the presence of digital ulcers. Decreased levels of TLR9 and JAK2 mRNA were found in the patient’s cohort in comparison to non-SSc individuals, but showed no correlation with specific clinical outcomes. The expression level of the STAT3 gene did not differ between the analyzed groups. This is the first study on the expression of TLR7, TLR9, and STAT3 genes in SSc patients. Our results show that TLR7, TLR9, and JAK2 genes are potential biomarkers for SSc. The results obtained in this study could contribute to better classification, monitoring, and outcome prediction of patients with SSc based on genetics.

Genetic characterization of GSD I in Serbian population revealed unexpectedly high incidence of GSD Ib and 3 novel SLC37A4 variants: SKAKICet al.

Glycogen storage disease (GSD) type I is inborn metabolic disease characterized by accumulation of glycogen in multiple organs. We analyzed 38 patients with clinical suspicion of GSD I using Sanger and next‐generation sequencing (NGS). We identified 28 GSD Ib and 5 GSD Ia patients. In 5 patients, GSD III, VI, IX, cholesteryl‐ester storage disease and Shwachman‐Diamond syndrome diagnoses were set using NGS. Incidences for GSD Ia and GSD Ib were estimated at 1:172 746 and 1:60 461 live‐births, respectively. Two variants were identified in G6PC gene: c.247C>T (p.Arg83Cys) and c.518T>C (p.Leu173Pro). In SLC37A4 gene, 6 variants were detected. Three previously reported variants c.81T>A (p.Asn27Lys), c.162C>A (p.Ser54Arg) and c.1042_1043delCT (p.Leu348Valfs*53) accounted for 87% of all analyzed alleles. Computational, transcription studies and/or clinical presentation in patients confirmed pathogenic effect of 3 novel variants: c.248G>A (p.Gly83Glu), c.404G>A (p.Gly135Asp) and c.785G>A (p.Ser263Glyfs*33 or p.Gly262Asp). In the cohort, hepatomegaly, hypoglycemia and failure to thrive were the most frequent presenting signs of GSD Ia, while hepatomegaly and recurrent bacterial infections were clinical hallmarks of GSD Ib. All GSD Ib patients developed neutropenia while 20.6% developed inflammatory bowel disease. Our study revealed the highest worldwide incidence of GSD Ib. Furthermore, description of 3 novel variants will facilitate medical genetic practice.

Use of Wilms Tumor 1 Gene Expression as a Reliable Marker for Prognosis and Minimal Residual Disease Monitoring in Acute Myeloid Leukemia With Normal Karyotype Patients

Micro‐Abstract The aim of the present study was to test the possibility for the usage of the WT1 (Wilms tumor 1) expression level as an additional biomarker for prognosis and minimal residual disease (MRD) monitoring in patients with acute myeloid leukemia with normal karyotype (AML‐NK). We found that overexpression of WT1 had a negative effect on treatment outcome. It was a suitable marker for MRD monitoring and a marker for refined risk stratification of AML‐NK patients. Background: Acute myeloid leukemia with normal karyotype (AML‐NK) represents the largest group of AML patients classified with an intermediate prognosis. A constant need exists to introduce new molecular markers for more precise risk stratification and for minimal residual disease (MRD) monitoring. Patients and Methods: Quantitative assessment of Wilms tumor 1 (WT1) gene transcripts was performed using real‐time polymerase chain reaction. The bone marrow samples were collected at the diagnosis from 104 AML‐NK patients and from 34 of these patients during follow‐up or disease relapse. Results: We found that overexpression of the WT1 gene (WT1high status), present in 25.5% of patients, was an independent unfavorable factor for achieving complete remission. WT1high status was also associated with resistance to therapy and shorter disease‐free survival and overall survival. Assessment of the log reduction value of WT1 expression, measured in paired diagnosis/complete remission samples, revealed that patients with a log reduction of < 2 had a tendency toward shorter disease‐free survival and overall survival and a greater incidence of disease relapse. Combining WT1 gene expression status with NPM1 and FLT3‐ITD mutational status, we found that the tumor behavior of intermediate patients (FLT3‐ITD−/NPM1− double negative) with WT1high status is almost the same as the tumor behavior of the adverse risk group. Conclusion: WT1 expression status represents a good molecular marker of prognosis, response to treatment, and MRD monitoring. Above all, the usage of the WT1 expression level as an additional marker for more precise risk stratification of AML‐NK patients could lead to more adapted, personalized treatment protocols.

Tetrahydrobiopterin deficiency among Serbian patients presenting with hyperphenylalaninemia

Abstract Hyperphenylalaninemia (HPA) [phenylketonuria (PKU) and tetrahydrobiopterin (BH4) deficiencies] is rare inborn metabolic disease characterized by elevated phenylalanine level in body fluids. In Serbia, 62 HPA patients have been identified through newborn screening since 1983. However, pterin pattern analysis is not performed. We present a patient initially diagnosed and treated as classical PKU. At 3 years of age, during infection with H1N1 influenza A virus, the patient first developed a neurologic crisis with encephalopathy and dystonic movements. We suspected that the patient is the first case of BH4 deficiency identified in Serbia. Genetic analyses showed that the patient does not have disease-causing variants of the PAH gene and carries a p.Asp136Val mutation in homozygous state in the PTS gene. For patients with treatable rare diseases, like PKU and BH4 deficiencies, correct diagnosis is crucial for the implementation of optimal treatment. If biochemical tests needed for differential diagnosis are not available, our experience emphasizes the necessity of immediate genetic testing after newborn screening.

Using Genetics for Enhancement (Liberal Eugenics)

Abstract The fascinating progress of genetics has led to great achievements in the modern, medical, and nonmedical sciences. Genetic engineering is used in many fields, among which human enhancement is one of the most controversial. Most bioethicists agree on the definition of human enhancement as a physical, cognitive, or moral improvement. Genetic enhancement refers to the introduction of the changes into a genome or epigenome intended to improve nonpathological human traits. It is expected that implementation of genetic enhancement will be reached through the discovery of markers in enhancement related genes, such as athletic performance- or aging-related genes, but also through the development of approaches characteristic for personalized medicine, such as gene enhancement, molecular-targeted enhancement, and cellular enhancement. However, we should be aware that genetic enhancement creates significant ethical and regulatory challenges. Prompt and thorough discussion between liberal eugenicists and bioconservatives is indispensable, because genetics is moving extremely fast toward human genetic enhancement.

Functional Analysis of an (A)γ-Globin Gene Promoter Variant (HBG1: g.-225_-222delAGCA) Underlines Its Role in Increasing Fetal Hemoglobin Levels Under Erythropoietic Stress.

Abstract Hereditary persistence of fetal hemoglobin (HPFH) is a condition characterized by persistent γ-globin gene expression and synthesis of high levels of fetal hemoglobin (Hb F; α2γ2) during adult life. It is usually caused by promoter variants or large deletions affecting the human fetal globin (HBG1 and HBG2) genes. Some of these HPFH-causing variants, such as HBG2: g.-158 C > T, exert their effect only under conditions of erythropoietic stress, typical for β-thalassemia (β-thal) patients. Namely, the presence of HBG2: g.-158 C > T favors a higher Hb F response, while it has little effect in healthy individuals. We analyzed a previously reported deletion residing in the promoter region of the HBG1 gene (HBG1: g.-225_-222delAGCA), both in normal conditions and under conditions of erythropoietic stress. Our results indicate that this deletion is responsible for decreased HBG1 gene expression. Specifically, this deletion was shown to result in drastically reduced reporter gene expression in K562 cells, compared to the wild-type sequence but only under conditions of erythropoietic stress, mimicked by introduction of erythropoietin (EPO) into the cell culture. Also, electrophoretic mobility shift analysis showed that the HBG1: g.-225_-222delAGCA deletion creates additional transcriptional factors’ binding sites, which, we propose, bind a transcriptional repressor, thus decreasing the HBG1 gene promoter activity. These results are consistent with in silico analysis, which indicated that this deletion creates a binding site for GATA1, known to be a repressor of the γ-globin gene expression. These data confirm the regulatory role of the HBG1: g.-225_-222 region that exerts its effect under conditions of erythropoietic stress characteristic for β-thal patients.

Novel Therapy Approaches in β-Thalassemia Syndromes — A Role of Genetic Modifiers

The β-thalassemia syndromes are heterogeneous autosomal recessive hereditary disorders, caused by alterations in the HBB gene and characterized by absent or reduced β-globin chain synthesis. The β-thalassemia phenotypes are variable, ranging from severe, transfusion-dependent thalassemia major to mild, asymptomatic thalassemia trait. This interpatient clinical variability has swayed researchers toward identifying genetic modifiers for these disorders. Primary modifiers refer to type of alterations affecting β-globin gene. Secondary modifiers include variations in genes affecting α/β-globin chain equilibrium, such as genes involved in the γ-globin gene expression and genes affecting the amount and stability of α-globin chains. Tertiary modifiers are gene variations affecting the phenotype with regard to the complications caused by β-thalassemia syndromes. A role of secondary genetic modifiers in ameliorating the clinical phenotype has been observed. Secondary genetic modifiers are the most common targets for modern therapy and could be located within αand γ-globin genes or outside globin gene cluster. The most potent secondary modifier genes are γ-globin genes. Production of fetal hemoglobin (HbF) trough adulthood ameliorates the severity of β-thalassemia phenotype. Large family and genome-wide association studies have shown that regions outside of the β-globin gene cluster are also implicated in γ-globin gene expression regulation. HBS1-MYB intragenic region and BCL11A gene have been particularly studied. Variants within these loci, along with γ-globin gene variants, account for approximately 50% of the HbF level variation, suggesting that additional factors are involved (transcription regulators (KLF1), regulators of α-globin chain stability (AHSP), epigenetic regulators (FoP)). Until recently a definitive cure for β-thalassemia could be achieved with bone marrow transplantation. However, it is available for less than 30% of the patients and bears a significant risk of morbidity and mortality. Alternative strategies, such as gene