Jornal de Biomarcadores Moleculares e Diagnóstico

Natriuretic peptides (NPs NP) are supposed to be important biomarkers as well as therapeutic medicines for cardiovascular diseases, however, there are still some controversies blocking the clinical application of NPs. Especially, natriuretic peptide receptors (NPRs) greatly interfere with the indicative efficiency, therapeutic effectiveness, clinical dosage, and medication time of NPs. Herein, we propose that the classification of cardiovascular patients will effectively promote the clinical utilization of NPs as either biomarkers or medicines. Generally, NPs bind to natriuretic peptide receptor A and B (NPRA and NPRB) to activate cellular signalings, but natriuretic peptide receptor C (NPRC) is mainly responsible for the clearance of NPs. So, it is expected that high NPs-sensitivity group includes individuals carrying the alleles that result in higher activity of NPRA and NPRB and lower activity of NPRC, while low NPs-sensitivity group is the opposite. Theoretically, the classification will improve the diagnostic accuracy of NPs for cardiovascular patients, and personalized administration of NPs-related medicines will benefit more individuals in order to achieve both of the maximum therapeutic efficacy and the minimum side effects.

The influence of smoking on the levels of several biomarkers of oxidative stress, antioxidant status and redox status have been investigated in 48 healthy men with a mean age of 25 y. The biomarkers of oxidative stress are the reactive oxygen metabolytes (ROM) and the total oxidant status (TOS). The biomarkers for the antioxidant activity are the biological antioxidant potential (BAP), the ferric reducing ability of plasma (FRAP), the total antioxidant status (TAS), the assay for the defense against the oxidation by hypochlorous acid (OXY) and uric acid (UA). The total thiol levels (TTL) have been measured as a biomarker for the redox status. The average concentration of ROM was 14% higher in smokers compared with non-smokers (p<0.05), whereas TOS was 4.9% higher (not statistically significant).The average concentrations of BAP, FRAP and TAS decreased with smoking with 3.6 (p<0.025), 3.6 (non-significant) and 6.1% (p<0.025), respectively. Alsouric acid, the main antioxidant in serum and a major contributor to the antioxidant status in serum, decreased by 10.6 % (p<0.025) in smokers. The biomarker of the redox status (TTL) was not influenced by smoking. From these results, it is concluded that in epidemiological studies the effect of smoking should be taken in account when using oxidative stress and antioxidant biomarkers.

Rheumatoid arthritis (RA) is characterized by progressive joint damage predominantly mediated by proinflammatory molecules including the tumor necrosis factor alpha (TNF-α). Several studies have addressed the relationship between diversity of TNF-α gene and susceptibility to RA and its clinical phenotypes but the results have been inconsistent. We conducted a case-control study to analyze the potential influence of three functionally relevant TNF-α promoter variants on RA incidence and disease phenotypes and serum TNF-α levels in a genetically homogeneous south Indian Tamil population. Genomic DNA from 269 RA patients and 233 healthy controls (HC) were analyzed by TaqMan 5’-nuclease assay for the distribution of the following SNPs: TNF-α -857 C>T (rs1799724), TNF-α -308 G>A (rs1800629) and TNF-α -238 G>A (rs 361525). We found that the frequency of the TNF-α -238 GG genotype and G allele was higher in patients as compared to controls [Pc: 0.004, OR: 2.01, CI 95%: 1.23-3.29 and Pc: 0.004, OR: 1.89, CI 95%: 1.22-2.97 respectively]. The genotype and allele frequency of TNF-α -857 C>T and -308 G>A polymorphisms did not differ between patients and controls. Haplotype analysis revealed that the frequency of ancestral TNF-α (-857,-308,-238) C-G-G haplotype was more in patients than in HC (80% vs 74%, P: 0.03, OR: 1.39, CI 95%: 1.02-1.89). The CGA haplotype was found at a higher frequency in HC than in patients (10.6% vs 7%, P: 0.03, OR: 0.61, CI 95%: 0.38-0.96). We also found that TNF-α-857T allele was associated with significantly high titers of circulating TNF-α. Our data suggest that TNF-α -238 G allele, -238 GG genotype and the TNF-α –C-G-G ancestral haplotype may be associated with susceptibility to RA. In addition, the TNF-α-857 C>T variant might influence the TNF-α production.

Gestational diabetes mellitus (GDM) is observed to be associated with increased perinatal morbidity and mortality. Screening for glucose intolerance during pregnancy provides an opportunity to offer management to those women diagnosed with gestational diabetes mellitus after first trimester. Elevated iron stores may induce diabetes through a variety of mechanisms, including oxidative damage to pancreatic beta cells, impairment of hepatic insulin extraction by the liver, and interference with insulin's ability to suppress hepatic glucose production. Raised Serum Ferritin could be related to the occurrence of long term complications of diabetes, both micro vascular and macro vascular. Iron affects glucose metabolism and glucose metabolism impinges on several iron metabolic processes. Iron overload decreases insulin sensitivity and cause earlier complications in diabetes mellitus. Iron plays a direct and causal role in diabetes pathogenesis mediated both by cell failure and insulin resistance. Iron also regulates metabolism in most tissues involved in fuel homeostasis, with the adipocyte in particular serving an iron-sensing role.

Epithelial cellular adhesion molecule (EpCAM) is a biomarker highly expressed on the surface of epithelial carcinoma cells. Consequently, it has been widely used for detection of carcinoma tumors and isolation of individual circulating cancer cells and EpCAM-targeting therapeutics are undergoing pre-clinical and clinical testing against several types of carcinomas. Aptamers are a new class of small oligonucleotide ligands that bind to their targets with high affinity and specificity, and are thus termed “chemical antibodies.” In comparison to protein antibodies, aptamers are smaller in size, which improves their tissue penetration potential, and elicit few to no immunogenic responses. Furthermore, our previous studies revealed that ssDNA, compared to RNA aptamers are significantly more stable in human serum and thus, are suitable for in vivo use. In this study, by using a hybrid cell-biomarker selection approach, we developed ssDNA-based aptamers specific for EpCAM. We identified a dominant aptamer sequence (58.7% of >0.5 million sequence reads) that contained both loop and stem structures, and specifically targeted EpCAM-expressing carcinoma cells with high binding affinity (Kd=12 nM). Validation studies indicated that the newly synthesized aptamer targeted a variety of cultured carcinoma cells, including pancreatic, breast, ovarian, prostate, and colon cancer cells, but did not react with cultured EpCAM-negative leukemia and lymphoma cells. In addition, the aptamer recognized EpCAM-expressing, patient-derived primary normal and carcinoma cells. Finally, the aptamer selectively targeted carcinoma cells in complex cell mixtures, and showed no reactivity to mononucleated or red blood cells, demonstrating its suitability for therapeutic in vivo use.

Aims/Introduction: Studies on the association between a deletion variant of the angiotensin-converting enzyme (ACE) gene and diabetic microalbuminuria and its impact on AGE/RAGE system remain inconclusive. Therefore, we aimed to study the association between ACE I/D polymorphism and the circulating levels of sRAGE (soluble receptor for advanced glycation end-products (sRAGE), pentosidine and advanced oxidation protein products (AOPPs) in type 2 diabetic patients with and without microalbuminuria.

Subjects and methods: ACE I/D polymorphism was analyzed using the amplified fragment length polymorphism Polymerase Chain Reaction method (AFLP). Circulating levels of sRAGE and pentosidine were assessed using enzyme linked immunosorbent assay, while AOPPs were assessed photometrically.

Results: within the diabetic normoalbuminuric group, DD and DI ACE genotypes were associated with significantly higher levels of sRAGE, Pentosidine and AOPPs (3280 ± 155 pg/mL, 289 ± 65 ng/ml and 192 ± 4.9 μmol/l ) respectively than those with the II genotype (2985 ± 310 pg/mL, 231 ± 66 ng/ml and 169 ± 7.5 μmol/l respectively, p<0.05). Also the microalbuminuric group exhibited a significant association between DD and DI ACE genotypes and higher levels of sRAGE, Pentosidine and AOPPs (10.2 ± 2.5%, 4975 ± 256 pg/mL, 305 ± 24 ng/ml and 207 ± 5.4 μmol/l ) respectively than those with the II genotype (4566 ± 219 pg/mL, 277 ± 15 ng/ml and 199 ± 7.6 μmol/l respectively, p<0.05).

Conclusions: Both ID and DD ACE genotypes might represent a risk factor for diabetic renal complications being associated with significantly higher levels of sRAGE, pentosidine and AOPPs.

Background: High incidences of respiratory ailments have been long attributed to rapid industrialization and fast economic growth in developing nations within Asia. Urbanization in particular has led to a significant increase in outdoor and indoor air pollution in Asian countries, affecting lung health for different population groups. Air pollutants enter the human systems via the inhalation pathway, and their measurement in exhaled breath has been suggested as a non-invasive alternative for early diagnosis of asthma and lung cancer. Routine monitoring of selected volatile organic compounds (VOCs) in breath often requires the use of robust analytical techniques with standardized sample collection procedures for reliable risk assessment. Currently, such analytical data are relatively sparse in the literature for Asian population groups due to lack of quantitative analysis of VOCs in exhaled breath. To fill the knowledge gap, a present pilot study was initiated to evaluate the suitability of an in situ instrumental technique for breath measurements among a small group of diverse Asian volunteers.

Methods: The study was conducted to explore the use of PTR-MS (Proton Transfer Reaction- Mass Spectrometry) with BET (Buffered End Tidal) breath sampling for real-time measurements of selected VOCs in healthy Asian volunteers (35 healthy subjects from different ethnic groups). Breath samples were analyzed for eight VOCs (well-known biomarkers) using BET-PTRMS, namely, acetone, isoprene, ethanol, acetaldehyde, acetonitrile, acrolein, benzene and toluene. The eight VOCs were confirmed independently using a complementary analytical technique (SPME-GCMS (Solid Phase Micro-Extraction-Gas Chromatography Mass Spectrometry)).

Results: Acetone (58% abundance) was found to be the predominant VOC, followed by isoprene (27%) and acetaldehyde (9%) in the breath samples of 35 healthy Asian healthy volunteers from diverse ethnic groups. Results obtained from the present study have been compared to those available in literature for different population groups.

Conclusion: Overall, BET-PTRMS is a promising real-time monitoring tool for measurements of suitable VOCs that can be used as breath signatures (“smell prints”) in Asian population groups as it demonstrated a high sensitivity and versatility required for successful practical applications. Further in-depth investigations with more number of subjects under clinical and sub-clinical settings are warranted to evaluate the potential of using BETPTRMS as a routine early diagnostic tool for Asian population groups at-risk of developing COPD, lung cancer or serious respiratory illnesses.

Introduction: Gilbert syndrome (GS) is due to a defect in uridine diphosphate glucuronosyl transferase (UGT1A1) gene and belongs to the group of the most common human metabolic disorders and is characterized by an elevated level of bilirubin in blood serum. Genotyping functional polymorphisms in UGT1A1 gene is an important step in the determination of the etiology of free hyperbilirubinemia of unknown origin. Herein, we aimed to explain the genetic profile and the clinical variability of this disease in Tunisian patients.

Material and methods: We explored a total of 30 subjects including 7 unrelated isolated cases and 23 subjects distributed to 7 families. The exploration of these subjects included the genotyping of two Functional polymorphisms of UGT1A1 gene associated with GS namely: A(TA)nTAA and G71R, the bilirubin level, the hematological parameters, the determination of glucose-6-phosphate dehydrogenase activity (G6PD) and echo dense images within the gall bladder with acoustic shadowing or gravitational change in position.

Results: The exploration of the hematological parameters showed that all subjects enrolled in this study are out of hemolytic disease with the exception of two individuals, it is a father and his son who have a profile of a β thalassemia minor. The exploration of G6PD activity showed that all patients presented normal values. All patients presented hyperbilirubinemia among whom some patients presented benign asymptomatic jaundice, two patients presented kernicterus and 4 patients presented cholelithiasis. The genetic profile studied of UGT1A1 revealed that the mutant allele A of the G71R polymorphism was absent for all subjects and that the genotype (TA)7/(TA)7 was associated with hyperbilirubinemia and with GS.

Spontaneous Bacterial Peritonitis (SBP) is an ascitic fluid infection without a definitive, surgically treatable, intraabdominal source, accounting for 10 to 30% of cirrhotic patients with ascites. To explore new methods of diagnosing Spontaneous Bacterial Peritonitis (SBP), we prospectively studied 19 Acute-on-Chronic Hepatitis B Liver Failure (ACHBLF) patients with or without Spontaneous Bacterial Peritonitis and 17 Hepatitis B Virus (HBV)-related Liver Decompensated Cirrhosis patients with or without Spontaneous Bacterial Peritonitis. Patients were separated into two groups: SBP group (n=14), non SBP group (n=22). A paracentesis of ascetic fluid was performed. The levels of 40 cytokines in ascetic fluid were measured by using RayBio® Human Cytokine Antibody Array. The results indicated that the levels of RANTES, EOTAXIN EOTAXIN-2, IL-1βand MIP-1αwere higher in the ascitic fluid of the SBP group. An increase in cytokine production in the ascitic fluid of patients with SBP may provide new markers to diagnose SBP more easily and accurately.

Background: Prostate Cancer (PCa) is a frequent malignancy worldwide. Prognosis of prostate cancer (PCa) is diverse with 80% not life-threatening even if untreated. In contrast, 20% are aggressive with short course of the disease. Hence the need for prognostic markers to predict aggressiveness, patients’ outcome, and efficacy of treatment is increasing.

Methods: We retrospectively analyzed serum and demographic data from 38 PCa-patients. Serum growth differentiation factor 15 (GDF15), hepcidin and interleukin-6 (IL-6) were measured.

Results: Serum GDF15 levels were higher in metastatic castration-resistant PCa patients with rapid disease progression than in metastatic PCa patients with slow disease progression. There was a trend to higher serum hepcidin - but not IL-6 - serum levels in patients with rapid disease progression than in slow disease progression. Prostate-specific antigen (PSA) correlated with serum GDF15 and hepcidin levels. Serum GDF15 levels correlated with serum hepcidin levels. The height of serum GDF15 and hepcidin levels correlated with survival of patients in months. Increase of 25 ng/ml serum hepcidin predicted an increase in mortality by 10%.

Conclusion: In conclusion, the current manuscript supports the use of serum GDF15 and serum hepcidin measurements as prognostic markers in PCa.

Background: Neuromyelitisoptica spectrum disorder (NMOSD) is a series of central nervous system diseases with positive aquaporin-4 antibody. And neurosyphilis is a manifestation of the late syphilis. Although Neuromyelitisoptica (NMO) following syphilis has been previously reported, transverse myelitis and neurosyphilis in the same patient with positive aquaporin-4 antibody has never been mentioned.

Method: We presented the coexistence of NMOSD and syphilis in a 72-year-oldChinese woman and analyzed the relationship of these two diseases. The pertinent literatures were also reviewed.

Result: Previous studies showed that syphilitic myelitis might be more frequent in male than in female and it tended to be asymptomatic. However our case was a woman who experienced acute attack, with positive AQP4 antibody. Therefore, her myelitis occurrence mainly associated with AQP4 antibodies autoimmunity, and neurosyphilis might be an asymptomatic episode in our case. Although there was no evidence that treponema pallidum subspecies pallidum involved in the pathogenesis of NMO, it seemed that anti-syphilitic treatment was helpful to attenuate disability in our present case.

Conclusion: Anti-NMO and anti-syphilitic treatment should be used together to treat the patient with both NMOSD and neurosyphilis.