G-Quadruplex Regulation of VEGFA mRNA Translation by RBM4

In eukaryotes, mRNAs translation is mainly mediated in a cap-dependent or cap-independent manner. The latter is primarily initiated at the internal ribosome entry site (IRES) in the 5′-UTR of mRNAs. It has been reported that the G-quadruplex structure (G4) in the IRES elements could regulate the IRES activity. We previously confirmed RBM4 (also known as LARK) as a G4-binding protein in human. In this study, to investigate whether RBM4 is involved in the regulation of the IRES activity by binding with the G4 structure within the IRES element, the IRES-A element in the 5′-UTR of vascular endothelial growth factor A (VEGFA) was constructed into a dicistronic reporter vector, psiCHECK2, and the effect of RBM4 on the IRES activity was tested in 293T cells. The results showed that the IRES insertion significantly increased the FLuc expression activity, indicating that this G4-containing IRES was active in 293T cells. When the G4 structure in the IRES was disrupted by base mutation, the IRES activity was significantly decreased. The IRES activity was notably increased when the cells were treated with G4 stabilizer PDS. EMSA results showed that RBM4 specifically bound the G4 structure in the IRES element. The knockdown of RBM4 substantially reduced the IRES activity, whereas over-expressing RBM4 increased the IRES activity. Taking all results together, we demonstrated that RBM4 promoted the mRNA translation of VEGFA gene by binding to the G4 structure in the IRES.

Genetic Polymorphisms Affecting Ranibizumab Response in High Myopia Patients

High myopia is an ophthalmic pathology that affects half of the young adults in the United States and Europe and it is predicted that a third of the world’s population could be nearsighted at the end of this decade. It is characterized by at least 6 diopters or axial length > 26 mm and, choroidal neovascularization (CNV) in 5 to 11% of cases. Ranibizumab is a recombinant humanized monoclonal antibody fragment. It is an anti-vascular endothelial growth factor (anti-VEGF) drug used in the treatment of CNV. Many genetic polymorphisms have been associated with interindividual differences in the response to ranibizumab, but these associations were not yet assessed among patients with high myopia and CNV. We performed a retrospective study assessing the association of genetic polymorphisms with response to ranibizumab in patients with CNV secondary to high myopia (mCNV). We included genetic polymorphisms previously associated with the response to drugs used in CNV patients (bevacizumab, ranibizumab, aflibercept, and photodynamic therapy (PDT)). We also included genetic variants in the VEGFA gene. Based on our results, ARMS2 (rs10490924) and CFH (rs1061170) are associated with response to ranibizumab in high myopia patients; and, included VEGFA genetic polymorphisms are not associated with ranibizumab response in our population but might be related to a higher risk of CNV.

Association of four gene polymorphisms in Chinese Guangxi population with diabetic retinopathy in type 2 diabetic patients

Abstracts Background Diabetic retinopathy (DR) is one of the most common chronic microvascular complications of diabetes. Many studies have suggested that genetic factors are important in the context of DR. This study evaluated the associations of GWAS (Genome-wide association study) -identified DR-associated SNPs in a Chinese population in Guangxi Province with type 2 diabetes mellitus (T2DM). Methods A total of 386 hospitalized T2DM patients without proliferative diabetic retinopathy (PDR) and 316 hospitalized T2DM patients with PDR were included in this case–control study. Four tag SNPs, including rs1800896 in the IL-10 gene, rs2010963 in the VEGFA gene, rs2070600 in the RAGE gene and rs2910164 in the miR-146a gene, were examined using KASP (kompetitive allele specific PCR) genotyping assays. Results There were no significant differences in the genotype or allele frequencies of the miR-146a polymorphism (rs2910164) between subjects with PDR and those without DR. The TC genotype of rs1800896 was determined to be associated with an increased risk of PDR (the odds ratio (OR) was 2.366, with a 95% confidence interval (CI) ranging from 1.144 to 4.894). The CG genotypes of rs2010963 was associated with an decreased risk of PDR (the OR was 0.588, with a 95% CI ranging from 0.366 to 0.946). Regarding rs2070600, 2 genotypes (TT and CT) were associated with a decreased risk of PDR (the OR of the TT genotype was 0.180, with a 95% CI ranging from 0.037 to 0.872, and the OR of the CT genotype was 0.448, with a 95% CI ranging from 0.266 to 0.753). Conclusions The rs1800896 polymorphisms in the IL-10 gene, rs2010963 in the VEGFA gene and rs2070600 in the RAGE gene are associated with the risk of PDR in the Han Chinese population of Guangxi Province. Our findings provide suggestive evidence that these polymorphisms may be involved in the pathogenesis of PDR and should be investigated further.

Analysis of Associative Relationship of Allelic and Genotypical Variants of Polymorphism Rs 2010963 of the VEGFA Gene with Formation and Development of Ronchopathy

It is interesting to note that the adverse effect of this genotype was observed exclusively in patients with ronchopathy, while in patients with ronchopathy, the frequency of this genotype did not differ in comparison with the control group, i.e. there is a significant tendency to an increase in the genotype with an increase in the severity of the pathology. Material and methods. To solve the set tasks, 208 patients with various diseases of the upper respiratory tract, with nasal breathing disorders, causing ronchopathy, who were hospitalized in the ENT department of the multidisciplinary clinic of the Tashkent Medical Academy for 2015 to 2021, were examined. The control group consisted of 50 apparently healthy people who agreed to participate in the study (students, masters, clinical residents). Among the sick men there were 144 (73%), women - 64 (27%). The age of the patients ranged from 18 to 70 years, averaging 44.5 ± 6.8 years. Molecular genetic studies were carried out in the Department of Molecular Medicine and Cell Technologies of the RSNPMC Hematology. This part of the work consisted of several stages: 1. Blood sampling. 2. Isolation of DNA from peripheral blood lymphocytes. 3. Carrying out PCR. 4. Conducting electrophoresis and visualizing the results (if necessary). The analysis of the TGFb1 gene polymorphism associations was carried out using a case-control model (casecontrol, comparison of two samples). The sample "case" was formed from 104 patients with ronchopathy. Conclusion. Since this work is one of the few works on the study of the relationship between rs 2010963 of the VEGFA gene and the risk of developing ronchopathy, our data may become the subject of further discussions.

Analysis of Associative Relationship of Allelic and Genotypical Variants of Polymorphism Rs 2010963 of the VEGFA Gene with Formation and Development of Ronchopathy

It is interesting to note that the adverse effect of this genotype was observed exclusively in patients with ronchopathy, while in patients with ronchopathy, the frequency of this genotype did not differ in comparison with the control group, i.e. there is a significant tendency to an increase in the genotype with an increase in the severity of the pathology. Material and methods. To solve the set tasks, 208 patients with various diseases of the upper respiratory tract, with nasal breathing disorders, causing ronchopathy, who were hospitalized in the ENT department of the multidisciplinary clinic of the Tashkent Medical Academy for 2015 to 2021, were examined. The control group consisted of 50 apparently healthy people who agreed to participate in the study (students, masters, clinical residents). Among the sick men there were 144 (73%), women – 64 (27%). The age of the patients ranged from 18 to 70 years, averaging 44.5 ± 6.8 years. Molecular genetic studies were carried out in the Department of Molecular Medicine and Cell Technologies of the RSNPMC Hematology. This part of the work consisted of several stages: 1. Blood sampling. 2. Isolation of DNA from peripheral blood lymphocytes. 3. Carrying out PCR. 4. Conducting electrophoresis and visualizing the results (if necessary). The analysis of the TGFb1 gene polymorphism associations was carried out using a case-control model (case-control, comparison of two samples). The sample “case” was formed from 104 patients with ronchopathy. Conclusion. Since this work is one of the few works on the study of the relationship between rs 2010963 of the VEGFA gene and the risk of developing ronchopathy, our data may become the subject of further discussions.

Association of four gene polymorphisms in Chinese Guangxi population with diabetic retinopathy in type 2 diabetic patients

Background: Diabetic retinopathy (DR) is one of the most common chronic microvascular complications of diabetes. Many studies have suggested that genetic factors are important in the context of DR. This study evaluated the associations of GWAS-identified DR-associated SNPs in a Chinese population in Guangxi Province with type 2 diabetes mellitus (T2DM).Methods: A total of 386 hospitalized T2DM patients without proliferative diabetic retinopathy (PDR) and 316 hospitalized T2DM patients with PDR were included in this case–control study. Four tag SNPs, rs1800896 in the IL-10 gene, rs2010963 in the VEGFA gene, rs2070600 in the RAGE gene and rs2910164 in the miR-146a gene, were examined using KASP (Kompetitive Allele Specific PCR) Genotyping Assays.Results: There were no significant differences in the genotype or allele frequencies of the miR-146a polymorphism (rs2910164) between subjects with DR and without DR. For rs1800896, the TT allele was determined to be associated with a decreased risk of PDR (P adjusted = 0.022). For rs2010963, 2 alleles (CC and GG) were associated with an increased risk of PDR (P adjusted-CC = 0.048, P adjusted-GG = 0.028). For rs2070600, 2 alleles (TT and CT) were associated with a decreased risk of PDR (P adjusted TT = 0.033, P adjusted CT = 0.002).Conclusions: The polymorphisms rs1800896 in the IL-10 gene, rs2010963 in the VEGFA gene and rs2070600 in the RAGE gene are associated with the risk of PDR in the Han Chinese population of Guangxi Province. Our findings provide suggestive evidence that these polymorphisms may be involved in the pathogenesis of PDR and should be investigated further.