Association of BARD1 and BRIP1 Gene Polymorphisms with the Risk of Uveal Melanoma

Considering the limited information about the role of hereditary predisposition to the development of uveal melanoma, we have performed an analysis of the frequencies of BARD1 (rs1048108, rs2229571, rs2070094) and BRIP1 (rs4986764) gene polymorphisms in patients with uveal melanoma and benign choroidal nevus in comparison with healthy volunteers (control). It has been found that the minor alleles of BRIP1 rs4986764 and BARD1 rs2070094 polymorphisms, as well as the homozygosity of T allele at the BARD1 rs1048108 locus are common genetic markers for the predisposition to uveal melanoma and benign choroidal nevus, while the homozygous genotype GG for the BARD1 rs2229571 polymorphism is a specific marker for the predisposition to uveal melanoma and progressive choroidal nevus. We have also found that the heterozygous genotype at BARD1 rs1048108 polymorphic locus is a specific marker for protection against uveal melanoma and progressive choroidal nevus. Thus, our results indicate the advisability of studying polymorphisms of the BARD1 gene (rs1048108, rs2229571, and rs2070094) and the BRIP1 gene (rs4986764) in patients with uveal melanoma and progressive choroidal nevus. The obtained findings can be used for forming risk groups, prevention of uveal melanoma, and differential diagnosis of intraocular neoplasms.

Methylation of the tumor associated genes in head and neck squamous cell carcinoma

Introduction. Head and neck cancer is a heterogenous group of malignant tumors of different etiologies, molecular mechanisms of which are still insufficiently studied.

Aim. Investigation of DNA methylation status of some tumor associated genes (RASSF1A, RASSF2, RASSF5, CDO1, MEST and WIF1) in patients with head and neck squamous cell carcinoma.

Materials and methods. The DNA methylation level of normal and tumor tissues was analyzed using bisulfite conversion and methylation-sensitive high-resolution melting in 25 patients (21 men and 4 women) diagnosed with neck squamous cell carcinoma.

Results. There were significant differences in levels of DNA methylation between tumor and normal tissues in the CDO1 and WIF1 genes in all groups and subgroups of patients (larynx and other cancers, squamous cell carcinoma keratinizing and non-keratinizing, primary and recurrent tumor, smokers and non-smokers). The methylation level in the CDO1 gene in tumor tissue was significantly increased in the T4 and T3 stage subgroups compared to T2.

Conclusion. The increased level of methylation of the CDO1 and WIF1 genes, as well as changes in their expression are among the molecular mechanisms involved in the neck squamous cell carcinoma development. They can be considered as prognostic and diagnostic markers for this pathology.

Assessment of the role of IL6 and IL10 gene polymorphisms as a risk factor for the development of restenosis in patients after implantation of drug-eluting stents

Relevance. Currently, the number of percutaneous coronary interventions continues to increase, which leads to an increase in the absolute number of restenosis cases, which is the main complication of the long-term postoperative period. The search for risk factors responsible for restenosis and artery re-narrowing mechanisms in order to prevent this complication is an important goal in interventional cardiology. Risk factors for the restenosis development include clinical, angiographic and genetic factors. An active search for biomolecular markers associated with the coronary artery restenosis is currently underway. Objective: to study the role of polymorphic variants C-174G of the IL6 gene and C-819T of the IL10 gene as a risk factor for the development of restenosis in patients after stent implantation. Materials and Methods : The study included 113 patients with stable coronary artery disease, who had previously undergone balloon angioplasty and implantation of drug-eluting stents, and 62 patients with intact arteries that were included to the control group. Statistical data processing was carried out using the R-language program and the SPSS Statistics 20 software package. Results: GG genotype for IL6 gene was associated with the development of coronary artery disease. In the subgroup of patients over 65 years of age and instent restenosis, the GG genotype was significantly less frequent. The homozygous CC genotype for IL10 gene was associated with rapid angiographic in-stent restenosis progression.

[Association of glutathione S-transferase gene polymorphism with risk of male infertility in Moscow region]

About 30% of male infertility is associated with genetic abnormalities. Genetic polymorphisms increase the level of individual susceptibility to adverse environmental factors and affect human reproductive function.

AIM

To study associations of glutathione S-transferase GSTP1(Ile/Val) gene polymorphisms (A313G; rs1695) with the risk of pathospermia in men of the Moscow region.

MATERIALS AND METHODS

We examined 138 men in the Moscow region (n=70 - proven pathospermia, n=68 - fertile men). We obtained genomic DNA from blood leukocytes and studied the gene polymorphisms of glutathione-S-transferase GSTP1 (Ile/Val) (A313G; rs1695) in real time.

RESULTS

In the analysis of the distribution frequencies of polymorphisms GSTP1 (Ile/Val) (A>G rs1695), we revealed the predominance of the AA genotype in fertile men and the predominance of the GG genotype (homozygous minor allele) in men with pathospermia. However, we found no significant difference in these parameters between the compared groups of patients (p=0.344). For GSTP1 (Ile/Val) polymorphism (A313G, rs1695), significant differences in the distribution of genotype frequencies in the subgroup of men with teratospermia (2=7.00; p=0.03) were revealed. The frequency of allele G in the subgroup of men with teratospermia is statistically significantly different from the frequencies of alleles in the control group: 52% versus 30% (2=10,004; p=0.0015). In subgroups of men with azoospermia and asthenospermia, we did not find significant differences in the distribution of genotypes of GSTP1 polymorphism (rs1695) (p>0.05).

DISCUSSION

Glutathione-S-transferase (GSTP1) is a multifunctional protein that protects sperm cells from the damaging effects of reactive oxygen species and xenobiotics. The Association of GSTP1 polymorphism (Ile/Val) (A313G, rs1695) with teratospermia explains the main stages of the pathogenesis of male infertility in this category of patients.

CONCLUSION

Gene polymorphism GSTP1 (A313G, rs1695) can be considered a genetic marker of susceptibility to pathospermia in men.

Vitamin D insufficiency as a risk factor for reproductive losses in miscarriage

OBJECTIVE

To study the relationship between vitamin D deficiency, VDR gene polymorphism rs10735810 (A > G), and a missed abortion in the first trimester of gestation; to determine the predictors of its risk.

RESEARCH METHODS

178 women aged between 18 and 41 were surveyed. The main group consisted of patients with miscarriage (n = 101), verified at the hospital stage (O02.0; O02.1), which were stratified by I group (n = 58, patients with the first miscarriage) and II groups (n = 43, patients with repeated miscarriage). The control group (n = 77) consisted of women with a successful pregnancy (Z34.0), which subsequently ended in delivery at term with a live fetus. Patients were surveyed and data was extracted from primary medical records. The level of 25(OH)D in the blood serum was investigated by mass spectrometry (n = 99). Genotyping for the vitamin D receptor gene polymorphism rs10735810 (VDR A > G) was performed for 177 patients. Statistical data analysis was performed via Statistica 10 and SAS JMP 11 application packages, using single-factor prediction for quantitative and binary factors, ROC analysis, and CHAID decision tree construction.

RESULTS OF THE STUDY

WE found that patients with miscarriage in the first trimester of gestation (n = 60) more frequently than those in the control group (n = 39) had vitamin D insufficiency (93.3% versus 76.9%, p = .0183) including its deficiency, occurring at 25(OH)D of blood <20 ng/ml (71.7% versus 51.3%, p = .0392). This pattern was found in patients with the first miscarriage, where significant differences in the frequency of vitamin D deficiency were also detected in comparison with the control group (80.0% versus 51.3%, p = .0026). No direct correlation was found between the frequency of miscarriages in the first trimester and the variant of the polymorphism of the vitamin D receptor gene (VDR A > G [rs10735810]); the GG genotype in patients with repeated miscarriages was even less frequent compared to the control group (14.0% versus 23.7%, p = .3344). However, the decision tree has identified four risk classes and has determined that the highest risk of missed abortion in the cohort studied is formed by three predicates: smoking, serum level 25(OH)D < 6.5 ng/ml and VDR AA and GG genotypes.

CONCLUSION

The data obtained show that vitamin D insufficiency plays a pathogenetically significant role in early reproductive losses associated with miscarriages, both first and recurrent.

Heat Shock Protein HSP60 in Left Ventricular Cardiomyocytes of Hypertensive Rats with and without Insulin-Dependent Diabetes Mellitus

In cardiomyocytes, high molecular ATP-dependent HSP70 and HSP90 play an important role in protecting the myocardium from abnormal proteins that appear, in particular, due to activation of oxidative stress. Molecular chaperone HSP60 is of particular importance for cardiomyocytes as it is responsible for assembly of mitochondrial matrix proteins. We studied the peculiarities of expression of HSP60 in left ventricular cardiomyocytes in hypertension, insulin-dependent diabetes mellitus, and their combination. The experiment was performed on 38-week-old male Wistar-Kyoto and SHR (spontaneously hypertensive) rats aged 38-57 weeks. Insulin-dependent diabetes mellitus was modeled by a single parenteral administration of 65 mg/kg streptozotocin. Expression of HSP60 in left ventricular cardiomyocytes was evaluated by immunohistochemical methods. It was found that hypertension, diabetes mellitus, and their combination are associated with a significant decrease in the content of HSP60 in left ventricular cardiomyocytes in comparison with the control. This finding can be considered as a pathogenetic mechanism of myocardial damage induced by hypertension and diabetes mellitus.

[Genetic aspects of primary hyperoxaluria: epidemiology, ethiology, pathogenesis, and clinical signs of the disorder]

Primary hyperoxaluria is a group of rare inherited diseases characterized by impaired oxalate metabolism with the early manifestation of urolithiasis and the development of the chronic kidney disease. The mutations in the AGXT, GRHPR, HOGA1 genes are attributable for different types of primary hyperoxaluria leading to the dysfunction of specific enzymes involved in the oxalate metabolism. The article summary the current data on the epidemiology, genetic and biochemical aspects of pathogenesis of the primary hyperoxaluria types 1-3. The variety of clinical signs and disease severity depend on the type of hyperoxaluria.

Prevalence of Some Gene Polymorphisms Related to Early Pregnancy Loss among Russian Women

Background. A variety of biological processes regulated by differential gene expression are required to maintain a normal gestation and accordingly, the mutations and polymorphisms in such genes may cause miscellaneous biological disorders that eventually result in early pregnancy loss. Many studies reported that aberrant fetal DNA methylation as well as embryonic chromosome abnormalities may lead to impairment of fetal early growth and development. Therefore, we have aimed to genotype several gene polymorphisms might be involved in the above-mentioned biological disorders to screen their prevalence in Russian population. Materials and methods. 81 Russian women without previous history of normal pregnancy or early abortion were recruited into this population study to determine the genotype and allele frequencies through genotyping using RFLP-PCR method for DNMT3B rs2424913, DNMT3B rs1569686, DNMT3A rs7590760, DNMT1 rs2228611, DNMT1 rs8101626, DNMT3L rs2276248, and DNMT3L rs2070565, allele-specific PCR for SYCP3 T657C, and real-time PCR for MTHFR rs1801133, MTHFR rs1801131, MTR rs1805087, and MTRR rs1801394. Results. Minor homozygous genotypes and minor alleles of the polymorphisms DNMT3B rs2424913 (TT: 11.1%, T: 37.05%), DNMT1 rs2228611 (GG: 18.5%, G: 40.75%), and DNMT1 rs8101626 (GG: 16.0%, G: 40.1%) were quite prevalent in Russian women and as frequent as those of the well-studied polymorphisms: MTRR rs1801394 (GG: 27.2%, G: 50.65%), MTHFR rs1801131 (CC: 17.3%, C: 40.15%), and MTHFR rs1801133 (TT: 11.1%, T: 29.0%).The heterozygous genotype of SYCP3 T657C (CT: 12.3%, T: 6.15%) was also quite frequent. Conclusion. Based on our study and literature data, we suggest that DNMT3B rs2424913, DNMT1 rs2228611, DNMT1 rs8101626, and SYCP3 T657C polymorphisms along with the common folate cycle gene polymorphisms can be potential genetic predictors for early pregnancy loss in Russian women.

[Genetic aspects of primary hyperoxaluria: diagnostics and treatment]

Primary hyperoxaluria is a group of inherited metabolic diseases characterized by increased formation of calcium-oxalate stones in kidneys with development of nephrolithiasis and chronic kidney disease. The article summarizes the modern information on the diagnostics and treatment of the disorder depending on genotype of the patient (AGXT, GRHPR, HOGA1 genes). The evaluation of the molecular genetic aetiology of the kidney stone disease contributes to the personalized treatment and prevention of the pathology in the patients and their relatives.

Association of DNMT3B and DNMN3L Gene Polymorphisms with Early Pregnancy Loss

A total of 100 women with early pregnancy loss were recruited and further classified into two subgroups: sporadic pregnancy loss and recurrent pregnancy loss; each subgroup consisted of 50 women. The control group included 56 women with normal pregnancies. Genotyping was performed by PCR with restriction fragment length polymorphism analysis. A statistically significant increase in the frequencies of TT genotype and T allele for DNMT3B rs2424913 polymorphism was found in the total patient group and in both patient subgroups in comparison with the control. Moreover, homozygous TT genotype was associated with increased risk of early pregnancy loss (both sporadic and recurrent). DNMT3B rs2424913 gene polymorphism in women can be used a marker of predisposition to early pregnancy loss and recurrent pregnancy loss.

Specific Features of Electrolyte Excretion at the Early Stages of Arterial Hypertension in SHR Rats

Daytime and nighttime systolic and diastolic BP was recorded in 23-week-old SHR and Wistar rats by telemetric monitoring. Urine concentrations of sodium, potassium, and calcium were determined in SHR rats during of light (07.00-19.00 h) and dark hours (19.00-07.00 h) at the age of 18, 19, 20, 21, 22, and 23 week; 23-week-old Wistar rats were used as the control. At early stages of the experiment, urine sodium concentration was elevated in SHR rats both at daytime and at night. Thereafter, this value declined and by 22-23 week was significantly lower than in normotensive Wistar rats, but only during daytime. Daytime potassium concentration significantly surpassed the control level during weeks 18-19 of the experiment, but later, a tendency to a decrease in this parameter was observed. Daytime calcium content in SHR rats did not significantly differ from the control throughout the experiment. At night, this value exceeded the control level by more than 2 times during weeks 18-19, but then returned to the level observed in normotensive animals.

Expression of Bax Protein and Morphological Changes in the Myocardium in Experimental Acute Pressure Overload of the Left Ventricle

The expression of Bax protein, marker of intracellular pathway of apoptosis initiation, in viable left ventricular cardiomyocytes and morphological changes in the myocardium in acute pressure overload of the left ventricle were studied in experiment on male rabbits. The content of Bax protein in the cardiomyocyte cytoplasm decreased, this indicating that the mitochondrial pathway was not involved in the realization of the apoptotic program. This decrease was associated with manifest destructive changes in the left ventricular myocardium.

Features of the Structure of the Circadian Rhythm of Blood Pressure and Heart Rate under Genetically Determined Hypertension in the Experiment

In SHR rats of different ages (22, 26, 30, 34, and 38 weeks), continuous 24-h telemetric monitoring of BP and HR was performed. The amplitude and power of oscillations of diastolic BP significantly decreased at the later stages of arterial hypertension (38 weeks), which was considered as a poor prognostic marker. We also observed a significant decrease in the mean daytime, nighttime, and maximum HR and mesor on weeks 30 and 34, but not on week 38, which can reflect triggering of the adaptive response followed by its exhaustion.

Effect of phosphocreatine and ethylmethylhydroxypyridine succinate on the expression of Bax and Bcl-2 proteins in left-ventricular cardiomyocytes of spontaneously hypertensive rats

We studied the effect of phosphocreatine and ethylmethylhydroxypyridine succinate on the expression of Bax and Bcl-2 proteins in left-ventricular cardiomyocytes of spontaneously hypertensive rats (SHR). Both drugs have no effect on the expression of Bcl-2, but significantly reduce the level of Bax protein (phosphocreatine produces more pronounced effect). These data attest to an important role of energy deficit and oxidative stress in the induction of cardiomyocyte apoptosis in genetically determined arterial hypertension.

Activities of some caspase cascade enzymes and myocardial contractility in experimental left ventricular focal ischemia

Focal left ventricular ischemia was modeled in male Chinchilla rabbits. Activities of caspase-3 and caspase-8 in the left and right ventricular myocardium and myocardial contractility were studied after 1, 3, and 5 days. Caspase-3 activity increased significantly in the left ventricular peri-infarction zone and right ventricular myocardium, while caspase-8 activity did not differ from the control. Left ventricular contractility decreased significantly and the hemodynamic load of the right ventricle sharply increased. These results attest to induction of the internal (mitochondrial) pathway of apoptosis in myocardial cells most likely caused by left ventricular hypoxia and right ventricular overload.

[The effect of ETA receptor blockade on cardiomyocyte apoptosis and myocardial hypertrophy development in genetically hypertensive rats]

Cardiomyocyte apoptosis and hypertrophy have been studied in the left and right ventricular myocardium of spontaneously hypertensive rats without treatment and after 10-day administration of the ETA-receptor antagonist BQ-123. It is established that BQ-123 prevents the activation of cardiomyocyte apoptosis and significantly decreases the extent of hypertrophy development in the left ventricular myocardium, but does not influence the same mechanisms in the right ventricular myocardium.