Expression of the NUP153 and YWHAB genes from their canonical promoters and alternative promoters of the LINE-1 retrotransposon in the placenta of the first trimester of pregnancy

The placenta has a unique hypomethylated genome. Due to this feature of the placenta, there is a potential possibility of using regulatory elements derived from retroviruses and retrotransposons, which are suppressed by DNA methylation in the adult body. In addition, there is an abnormal increase in the level of methylation of the LINE-1 retrotransposon in the chorionic trophoblast in spontaneous abortions with both normal karyotype and aneuploidy on different chromosomes, which may be associated with impaired gene transcription using LINE-1 regulatory elements. To date, 988 genes that can be expressed from alternative LINE-1 promoters have been identified. Using the STRING tool, genes (NUP153 and YWHAB) were selected, the products of which have significant functional relationships with proteins highly expressed in the placenta and involved in trophoblast differentiation. This study aimed to analyze the expression of the NUP153 and YWHAB genes, highly active in the placenta, from canonical and alternative LINE-1 promoters in the germinal part of the placenta of spontaneous and induced abortions. Gene expression analysis was performed using real-time PCR in chorionic villi and extraembryonic mesoderm of induced abortions (n = 10), adult lymphocytes (n = 10), spontaneous abortions with normal karyotype (n = 10), and with the most frequent aneuploidies in the first trimester of pregnancy (trisomy 16 (n = 8) and monosomy X (n = 6)). The LINE-1 methylation index was assessed in the chorionic villi of spontaneous abortions using targeted bisulfite massive parallel sequencing. The level of expression of both genes from canonical promoters was higher in blood lymphocytes than in placental tissues (p < 0.05). However, the expression level of the NUP153 gene from the alternative LINE-1 promoter was 17 times higher in chorionic villi and 23 times higher in extraembryonic mesoderm than in lymphocytes (p < 0.05). The expression level of NUP153 and YWHAB from canonical promoters was higher in the group of spontaneous abortions with monosomy X compared to all other groups (p < 0.05). The LINE-1 methylation index negatively correlated with the level of gene expression from both canonical (NUP153 – R = –0.59, YWHAB – R = –0.52, p < 0.05) and alternative LINE-1 promoters (NUP153 – R = –0.46, YWHAB – R = –0.66, p < 0.05). Thus, the observed increase in the LINE-1 methylation index in the placenta of spontaneous abortions is associated with the level of expression of the NUP153 and YWHAB genes not only from alternative but also from canonical promoters, which can subsequently lead to negative consequences for normal embryogenesis

Метаболизм оксида азота и лейкотриена Е4 при бронхоспазме, вызванном физической нагрузкой, у лыжников и биатлонистов в различные периоды годового тренировочного цикла

The purpose of the study was to investigate respiratory metabolism of nitric oxide (NO) and urinary LT E4 excretion in exerciseinduced bronchoconstriction (EIB)positive and EIB-negative skiers and biathlonists in different periods of training season.Materials and methods. 92 athletes were examined in precompetitive period and 78 in competitive period of annual training cycle (mean age, 17.5 ± 2.3 years). A control group included 64 healthy non sporty individuals of similar age. EIB was diagnosed using an indirect exercise fieldtest at subfreezing ambient temperature (MasterScreen Pneumo, Jaeger). Pre and postexercise fractional exhaled NO level (FeNO), exjhaled breath condensate (EBC) levels of NO2/NO3 (R&D Systems, USA) and 3-nitrotyrosine (Hycult biotech, Netherlands) were studied. Urinary LT Е4 excretion (Assay Designs, USA) was investigated by ELISA.Results. NO2/NO3 and 3-nitrotyrosine levels in EBC were significantly different in athletes and control group. Skiers and biathlonists demonstrated significantly higher 3-nitrotyrosine level and lower NO2/NO3 level in the competitive period compared to the precompetitive period. EIB-positive athletes had lower baseline FeNO, higher levels of NO metabolites in the EBC. However, significant differences were found only in preexercise NO2 level. Urinary LT E4 was significantly higher in athletes than in controls and did not differ between EIB-positive and EIB-negative athletes. There was a negative relationship between pre and postexercise FEV1 and urinary cysLT E4 level.Conclusion. Repetitive intensive exercise in subfreezing ambient temperature could modify respiratory NO metabolism and cysLT production in athletes.Целью исследования явилось изучение метаболизма оксида азота (NO) и уровня экскреции лейкотриена (ЛТ) Е4 с мочой у лыжников и биатлонистов с бронхоспазмом, вызванным физической нагрузкой (БФН), в различные периоды годового тренировочного цикла. Обследованы спортсмены (средний возраст – 17,5 ± 2,3 года) в подготовительном (n = 92) и соревновательном (n = 78) периодах. Группу контроля составили здоровые добровольцы (n = 64) сходной возрастной группы, не занимающиеся спортом профессионально. Для выявления БФН использовался тест с физической нагрузкой (ФН) на открытом воздухе при низких температурах окружающей среды с динамической оценкой показателей функции внешнего дыхания, полученных с помощью спирографа MasterScreen Pneumo (Jaeger, Германия). Определение содержания фракции NO в выдыхаемом воздухе (FeNO), соотношения нитрит (NO2) и нитратанионов (NO3) производилось на оборудовании R&D Systems (США), 3-нитротирозина (3-NT) в конденсате выдыхаемого воздуха (КВВ) выполнялось до и после ФН с помощью набора реагентов Hycult biotech (Нидерланды). Также исследован уровень ЛТ Е4 в моче с помощью иммуноферментного анализа (Assay Designs, США) с коррекцией по уровню креатинина. Содержание NO2 / NO3, 3-NT в КВВ значимо различались у спортсменов и лиц, не занимающихся профессиональным спортом. Уровень 3-NT был значимо выше у спортсменов, обследованных в соревновательном периоде макроцикла. В этом периоде отмечена достоверно меньшая суммарная концентрация NO2 / NO3. У спортсменов с БФН определены значимо более низкий исходный уровень FeNO, более высокое содержание метаболитов NO в КВВ, однако достоверные различия зафиксированы только по исходному уровню NO2. Уровень ЛТ E4 был значимо выше у спортсменов в сравнении с контролем и не отличался в зависимости от наличия / отсутствия БФН. Выявлены отрицательные взаимосвязи исходного и постнагрузочного ОФВ1 и уровня cysЛТ в моче. Полученные результаты свидетельствуют о модификации респираторного метаболизма NO, а также увеличении продукции cysЛТ под действием интенсивной ФН в условиях низкой температуры окружающей среды у лыжников и биатлонистов

The Telomere Binding Protein TRF2 Induces Chromatin Compaction

Mammalian telomeres are specialized chromatin structures that require the telomere binding protein, TRF2, for maintaining chromosome stability. In addition to its ability to modulate DNA repair activities, TRF2 also has direct effects on DNA structure and topology. Given that mammalian telomeric chromatin includes nucleosomes, we investigated the effect of this protein on chromatin structure. TRF2 bound to reconstituted telomeric nucleosomal fibers through both its basic N-terminus and its C-terminal DNA binding domain. Analytical agarose gel electrophoresis (AAGE) studies showed that TRF2 promoted the folding of nucleosomal arrays into more compact structures by neutralizing negative surface charge. A construct containing the N-terminal and TRFH domains together altered the charge and radius of nucleosomal arrays similarly to full-length TRF2 suggesting that TRF2-driven changes in global chromatin structure were largely due to these regions. However, the most compact chromatin structures were induced by the isolated basic N-terminal region, as judged by both AAGE and atomic force microscopy. Although the N-terminal region condensed nucleosomal array fibers, the TRFH domain, known to alter DNA topology, was required for stimulation of a strand invasion-like reaction with nucleosomal arrays. Optimal strand invasion also required the C-terminal DNA binding domain. Furthermore, the reaction was not stimulated on linear histone-free DNA. Our data suggest that nucleosomal chromatin has the ability to facilitate this activity of TRF2 which is thought to be involved in stabilizing looped telomere structures

A transcriptome-wide association study among 97,898 women to identify candidate susceptibility genes for epithelial ovarian cancer risk

Large-scale genome-wide association studies (GWAS) have identified approximately 35 loci associated with epithelial ovarian cancer (EOC) risk. The majority of GWAS-identified disease susceptibility variants are located in non-coding regions, and causal genes underlying these associations remain largely unknown. Here we performed a transcriptome-wide association study to search for novel genetic loci and plausible causal genes at known GWAS loci. We used RNA sequencing data (68 normal ovarian-tissue samples from 68 individuals and 6,124 cross-tissue samples from 369 individuals) and high-density genotyping data from European descendants of the Genotype-Tissue Expression (GTEx V6) project to build ovarian and cross-tissue models of genetically regulated expression using elastic net methods. We evaluated 17,121 genes for their cis-predicted gene expression in relation to EOC risk using summary statistics data from GWAS of 97,898 women, including 29,396 EOC cases. With a Bonferroni-corrected significance level of P<2.2×10-6, we identified 35 genes including FZD4 at 11q14.2 (Z=5.08, P=3.83×10-7, the cross-tissue model; 1 Mb away from any GWAS-identified EOC risk variant), a potential novel locus for EOC risk. All other 34 significantly-associated genes were located within 1 Mb of known GWAS-identified loci, including 23 genes at 6 loci not previously linked to EOC risk. Upon conditioning on nearby known EOC GWAS-identified variants, the associations for 31 genes disappeared and 3 genes remained (P<1.47 x 10-3). These data identify one novel locus (FZD4) and 34 genes at 13 known EOC risk loci associated with EOC risk, providing new insights into EOC carcinogenesis

Polygenic risk modeling for prediction of epithelial ovarian cancer risk

Polygenic risk scores (PRS) for epithelial ovarian cancer (EOC) have the potential to improve risk stratification. Joint estimation of Single Nucleotide Polymorphism (SNP) effects in models could improve predictive performance over standard approaches of PRS construction. Here, we implemented computationally efficient, penalized, logistic regression models (lasso, elastic net, stepwise) to individual level genotype data and a Bayesian framework with continuous shrinkage, "select and shrink for summary statistics" (S4), to summary level data for epithelial non-mucinous ovarian cancer risk prediction. We developed the models in a dataset consisting of 23,564 non-mucinous EOC cases and 40,138 controls participating in the Ovarian Cancer Association Consortium (OCAC) and validated the best models in three populations of different ancestries: prospective data from 198,101 women of European ancestries; 7,669 women of East Asian ancestries; 1,072 women of African ancestries, and in 18,915 BRCA1 and 12,337 BRCA2 pathogenic variant carriers of European ancestries. In the external validation data, the model with the strongest association for non-mucinous EOC risk derived from the OCAC model development data was the S4 model (27,240 SNPs) with odds ratios (OR) of 1.38 (95% CI: 1.28-1.48, AUC: 0.588) per unit standard deviation, in women of European ancestries; 1.14 (95% CI: 1.08-1.19, AUC: 0.538) in women of East Asian ancestries; 1.38 (95% CI: 1.21-1.58, AUC: 0.593) in women of African ancestries; hazard ratios of 1.36 (95% CI: 1.29-1.43, AUC: 0.592) in BRCA1 pathogenic variant carriers and 1.49 (95% CI: 1.35-1.64, AUC: 0.624) in BRCA2 pathogenic variant carriers. Incorporation of the S4 PRS in risk prediction models for ovarian cancer may have clinical utility in ovarian cancer prevention programs

Association of genomic domains in BRCA1 and BRCA2 with prostate cancer risk and aggressiveness

Pathogenic sequence variants (PSV) in BRCA1 or BRCA2 (BRCA1/2) are associated with increased risk and severity of prostate cancer. Weevaluated whether PSVs inBRCA1/2 were associated with risk of overall prostate cancer or high grade (Gleason 8+) prostate cancer using an international sample of 65 BRCA1 and 171 BRCA2 male PSV carriers with prostate cancer, and 3,388 BRCA1 and 2,880 BRCA2 male PSV carriers without prostate cancer. PSVs in the 30 region of BRCA2 (c.7914+) were significantly associated with elevated risk of prostate cancer compared with reference bin c.1001c.7913 [HR = 1.78; 95% confidence interval (CI), 1.25-2.52; P = 0.001], as well as elevated risk of Gleason 8+ prostate cancer (HR = 3.11; 95% CI, 1.63-5.95; P = 0.001). c.756-c.1000 was also associated with elevated prostate cancer risk (HR = 2.83; 95% CI, 1.71-4.68; P = 0.00004) and elevated risk of Gleason 8+prostate cancer (HR = 4.95; 95% CI, 2.12-11.54; P = 0.0002). No genotype-phenotype associations were detected for PSVs in BRCA1. These results demonstrate that specific BRCA2 PSVs may be associated with elevated risk of developing aggressive prostate cancer. Significance: Aggressive prostate cancer risk in BRCA2 mutation carriers may vary according to the specific BRCA2 mutation inherited by the at-risk individual.Peer reviewe

ЭФФЕКТИВНОСТЬ ПОДДЕРЖИВАЮЩЕЙ ТЕРАПИИ ПОСЛЕ ОКОНЧАНИЯ ПЕРВОЙ ЛИНИИ ЛЕЧЕНИЯ БОЛЬНЫХ МЕТАСТАТИЧЕСКИМ РАКОМ ТОЛСТОЙ КИШКИ – РЕЗУЛЬТАТЫ ПОПУЛЯЦИОННОГО ИССЛЕДОВАНИЯ

Aim. To evaluate the effectiveness of different regimens of maintenance chemotherapy after the first line of treatment for patients with metastatic colorectal cancer.Materials and methods. We performed retrospective analyses of the data from 432 patients from 17 clinics in 14 regions of the Russian Federation who started systemic therapy for metastatic cancer in 2013. The main inclusion criterion was objective response or stabilization after the first 16 weeks of first-line therapy. Four groups of patients were compared, depending on the nature of maintenance therapy: those receiving fluoropyrimidines, a combination of fluoropyrimidines with bevacizumab, monotherapy of bevacizumab and monotherapy of anti-EGFR antibodies. The main criteria for assesment of the effectiveness of treatment were progression-free survival and overall survival. The statistical analysis was performed with the SPSS 20.0 sof tware package.Results. Maintenance therapy after completion of the first 16 weeks of the 1st line of chemotherapy was administered in 126 patients, most of them were treated with fluoropyrimidines (53.1 %). The median overall survival in the maintenance group was 27 versus 21 months in the observation group, p=0.01, HR=0.78 (95 % CI 0.6–1.02) Median progression-free survival in the maintenance group was 11 vs 7 months in the observation group (p&lt;0.001, HR=0.6, 95 % CI 0.5–0.8). The worst results of progression-free survival were observed in the group with monotherapy of bevacizumab – median was 10 months versus 12 months in the fluoropyrimidine monotherapy group, 10 months for the combination of fluoropyrimidine with bevacizumab and 14 months for monotherapy of the anti-EGFR (p=0,9, HR=1.0, 95 % CI 0.9–1.2).Conclusions. There were no statistical differences in survival with different regimens of maintenance therapy. Monotherapy of bevacizumab in maintenance treatment was associated with the worst sur vival rates.Цель. Оценить эффективность различных режимов поддерживающей терапии после окончания первой линии лечения больных метастатическим раком толстой кишки.Материалы и методы. Проведен анализ индивидуальных карт 432 пациентов 17 клиник 14 регионов РФ, которые начали терапию по поводу метастатического рака в 2013 г. Основным критерием отбора в исследование являлось отсутствие прогрессирования в течение первых 16 нед. терапии первой линии. Проведено сравнение четырех групп пациентов в зависимости от характера поддерживающей терапии: получавших фторпиримидины, комбинацию фторпиримидинов с бевацизумабом, бевацизумаб в монорежиме и анти-EGFR антитела. Основными критериями оценки эффективности лечения считались выживаемость без прогрессирования и общая выживаемость. Статистический анализ проводился в пакете программ SPSS 20.0.Результаты. Поддерживающая терапия после завершения первой линии лечения была назначена 126 пациентам, большинству проводилась терапия фторпиримидинами (53,1 %). Медиана продолжительности жизни в группе поддерживающей терапии составила 27 мес. против 21 мес. в группе наблюдения (р=0,01, ОР=0,78, 95 % ДИ 0,6–1,02). Медиана выживаемости без прогрессирования – 11 против 7 мес. (p&lt;0,001, ОР=0,6, 95 % ДИ 0,5–0,8). Наихудшие результаты выживаемости без прогрессирования наблюдались в группе поддерживающего лечения мототерапии бевацизумабом: медиана 10 мес. против 12 мес. в группе монотерапии фторпиримидинами, 10 мес. в группе комбинации фторпиримидинов с бевацизумабом и 14 мес. в группе монотерапии анти-EGFR антителами (р=0,9, ОР=1,0, 95 % ДИ 0,9–1,2).Выводы. Не получено статистических различий в выживаемости при применении различных режимов поддерживающей терапии. Монотерапия бевацизумабом в поддерживающем лечении была ассоциирована с наименьшими показателями выживаемости пациентов

Clinical features of post-COVID-19 period. Results of the international register “Dynamic analysis of comorbidities in SARS-CoV-2 survivors (AKTIV SARS-CoV-2)”. Data from 6-month follow-up

Aim. To study the clinical course specifics of coronavirus disease 2019 (COVID-19) and comorbid conditions in COVID-19 survivors 3, 6, 12 months after recovery in the Eurasian region according to the AKTIV register. Material and methods.The AKTIV register was created at the initiative of the Eurasian Association of Therapists. The AKTIV register is divided into 2 parts: AKTIV 1 and AKTIV 2. The AKTIV 1 register currently includes 6300 patients, while in AKTIV 2 — 2770. Patients diagnosed with COVID-19 receiving in- and outpatient treatment have been anonymously included on the registry. The following 7 countries participated in the register: Russian Federation, Republic of Armenia, Republic of Belarus, Republic of Kazakhstan, Kyrgyz Republic, Republic of Moldova, Republic of Uzbekistan. This closed multicenter register with two nonoverlapping branches (in- and outpatient branch) provides 6 visits: 3 in-person visits during the acute period and 3 telephone calls after 3, 6, 12 months. Subject recruitment lasted from June 29, 2020 to October 29, 2020. Register will end on October 29, 2022. A total of 9 fragmentary analyzes of the registry data are planned. This fragment of the study presents the results of the post-hospitalization period in COVID-19 survivors after 3 and 6 months. Results. According to the AKTIV register, patients after COVID-19 are characterized by long-term persistent symptoms and frequent seeking for unscheduled medical care, including rehospitalizations. The most common causes of unplanned medical care are uncontrolled hypertension (HTN) and chronic coronary artery disease (CAD) and/or decompensated type 2 diabetes (T2D). During 3- and 6-month follow-up after hospitalization, 5,6% and 6,4% of patients were diagnosed with other diseases, which were more often presented by HTN, T2D, and CAD. The mortality rate of patients in the post-hospitalization period was 1,9% in the first 3 months and 0,2% for 4-6 months. The highest mortality rate was observed in the first 3 months in the group of patients with class II-IV heart failure, as well as in patients with cardiovascular diseases and cancer. In the pattern of death causes in the post-hospitalization period, following cardiovascular causes prevailed (31,8%): acute coronary syndrome, stroke, acute heart failure. Conclusion. According to the AKTIV register, the health status of patients after COVID-19 in a serious challenge for healthcare system, which requires planning adequate health system capacity to provide care to patients with COVID-19 in both acute and post-hospitalization period