A common polymorphism in the 5'-untranslated region of the VEGF gene is associated with diabetic retinopathy in type 2 diabetes

Factors Influencing Collateral Circulation Formation After Indirect Revascularization for Moyamoya Disease: a Narrative Review

Indirect revascularization is one of the main techniques for the treatment of Moyamoya disease. The formation of good collateral circulation is a key measure to improve cerebral blood perfusion and reduce the risk of secondary stroke, and is the main method for evaluating the effect of indirect revascularization. Therefore, how to predict and promote the formation of collateral circulation before and after surgery is important for improving the success rate of indirect revascularization in Moyamoya disease. Previous studies have shown that vascular endothelial growth factor, endothelial progenitor cells, Caveolin-1, and other factors observed in patients with Moyamoya disease may play a key role in the generation of collateral vessels after indirect revascularization through endothelial hyperplasia and smooth muscle migration. In addition, mutations in the genetic factor RNF213 have also been associated with this process. This study summarizes the factors and mechanisms influencing collateral circulation formation after indirect revascularization in Moyamoya disease.

New insights on genetic background of major diabetic vascular complications

BACKGROUND

By 2045, it is expected that 693 million individuals worldwide will have diabetes and with greater risk of morbidity, mortality, loss of vision, renal failure, and a decreased quality of life due to the devastating effects of macro- and microvascular complications. As such, clinical variables and glycemic control alone cannot predict the onset of vascular problems. An increasing body of research points to the importance of genetic predisposition in the onset of both diabetes and diabetic vascular complications.

OBJECTIVES

Purpose of this article is to review these approaches and narrow down genetic findings for Diabetic Mellitus and its consequences, highlighting the gaps in the literature necessary to further genomic discovery.

MATERIAL AND METHODS

In the past, studies looking for genetic risk factors for diabetes complications relied on methods such as candidate gene studies, which were rife with false positives, and underpowered genome-wide association studies, which were constrained by small sample sizes.

RESULTS

The number of genetic findings for diabetes and diabetic complications has over doubled due to the discovery of novel genomics data, including bioinformatics and the aggregation of global cohort studies. Using genetic analysis to determine whether diabetes individuals are at the most risk for developing diabetic vascular complications (DVC) might lead to the development of more accurate early diagnostic biomarkers and the customization of care plans.

CONCLUSIONS

A newer method that uses extensive evaluation of single nucleotide polymorphisms (SNP) in big datasets is Genome-Wide Association Studies (GWAS).

Genetic Background of Medication-Related Osteonecrosis of the Jaw: Current Evidence and Future Perspectives

Medication-related osteonecrosis of the jaw (MRONJ) is a rare side effect of antiresorptive drugs that significantly hinders the quality of life of affected patients. The disease develops in the presence of a combination of factors. Important pathogenetic factors include inflammation, inhibition of bone remodeling, or genetic predisposition. Since the first description of this rare side effect in 2003, a growing body of data has suggested a possible role for genetic factors in the disease. Several genes have been suggested to play an important role in the pathogenesis of MRONJ such as SIRT1, VEGFA, and CYP2C8. With the development of molecular biology, newer methods such as miRNA and gene expression studies have been introduced in MRONJ, in addition to methods that can examine the base sequence of the DNA. Describing the complex genetic background of MRONJ can help further understand its pathophysiology as well as identify new therapeutic targets to better manage this adverse drug reaction.

Genetic insights and emerging therapeutics in diabetic retinopathy: from molecular pathways to personalized medicine

Diabetic retinopathy (DR) is a major complication of diabetes worldwide, significantly causing vision loss and blindness in working-age adults, and imposing a substantial socioeconomic burden globally. This review examines the crucial role of genetic factors in the development of DR and highlights the shift toward personalized treatment approaches. Advances in genetic research have identified specific genes and variations involved in angiogenesis, inflammation, and oxidative stress that increase DR susceptibility. Understanding these genetic markers enables early identification of at-risk individuals and the creation of personalized treatment plans. Incorporating these genetic insights, healthcare providers can develop early intervention strategies and tailored treatment plans to improve patient outcomes and minimize side effects. This review emphasizes the transformative potential of integrating genetic information into clinical practice, marking a paradigm shift in DR management and advancing toward a more personalized and effective healthcare model.

Association Between Vascular Endothelial Growth Factor (VEGF) +936C/T Polymorphism (rs3025039) and Preeclampsia Among Myanmar Pregnant Women

Background: The vascular endothelial growth factor (VEGF) polymorphism is associated with preeclampsia since its abnormal expression plays an important role in vasculogenesis in placenta formation. Thus, this study is aimed at analyzing the association between VEGF +936C/T polymorphism and the risk of preeclampsia. Methods: To assess the causal relationship, a hospital-based cross-sectional analytical study was carried out among 204 Myanmar pregnant women during the period of January 2018-September 2020. For data collection, a pretested, structured questionnaire was used. Blood samples were collected after obtaining consent, and then we studied the extracted gene by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The Statistical Package for Social Sciences version 18.0 was used for data management and analysis. Results: The genotype CT variant among preeclamptic women was more than that of non-preeclamptic women (26.5% vs. 18.6%), but not significant (p = 0.180). The risk of preeclampsia among women with CT genotypes was 1.57 times higher than that of women with CC genotypes (OR (95%CI) = 1.57 (0.81, 3.06), p = 0.180). The minor allele frequency of the T allele was 15.2% in preeclamptic women and 9.3% in normal pregnant women. The risk of preeclampsia among T allele carriers is 1.49 times (95%CI = 0.80, 2.77) more than that of C allele carriers (p = 0.211). Among the preeclamptic pregnant women, the frequency of the CT genotype was 26.3% in the severe preeclamptic group and 26.9% in the mild preeclamptic group, while the frequency of the T allele was 13.2% and 13.5%, respectively. The frequency of either CT genotype or T allele was more or less the same in both groups, and there was no association between VEGF C/T polymorphism and the severity of preeclampsia. After logistic regression analysis on VEGF genotype and clinical parameters such as age, maternal body mass index (BMI), and neonatal birth weight, the risk of preeclampsia was 2.1 times higher in pregnant women with CT genotype compared to CC genotype (adjusted OR, 2.1; 95% CI, 0.9-4.5, p value -0.057). Conclusion: There was no significant association between VEGF +936C/T polymorphism (rs3025039) and preeclampsia among Myanmar pregnant women. However, the findings of this study highlighted that individuals carrying either the CT genotype or the T allele are at a heightened risk of developing preeclampsia. Furthermore, it suggests a potential impact of the gene on the occurrence of preeclampsia, yet the data lacks sufficient evidence to establish statistical significance.

Association of Vascular Endothelial Growth Factor (VEGF) and Mouse Model Minute 2 (MDM2) Polymorphisms With Diabetic Retinopathy in a Northwest Indian Population: A Case-Control Study

INTRODUCTION

Diabetic retinopathy (DR), a microvascular complication of type 2 diabetes (T2D), results from complex interactions of genetic and environmental factors. Vascular endothelial growth factor (VEGF) and mouse model minute 2 (MDM2)are upregulated in the retina due to diabetes, which increases the risk of DR. VEGFA and MDM2 genetic variations can influence DR risk. The present case-control study was conducted to evaluate the association of VEGFA and MDM2 promoter variants with DR in a population from Punjab, Northwest India.

METHODS

A total of 414 DR patients, 425 T2D patients without DR, and 402 healthy controls were screened for VEGFA -2578C/A (rs699947), VEGFA -2549I/D (rs35569394), VEGFA -7C/T (rs25648), and MDM2 rs3730485 polymorphisms using polymerase chain reaction (PCR)-based methods.

RESULTS

VEGFA -2549 I allele (OR = 1.35 (1.00-1.81), p = 0.043) and II genotype (OR = 1.78 (1.00-3.15), p = 0.047) were significantly associated with increased risk of DR. VEGFA -7 CT genotype conferred reduced risk of DR (OR = 0.28 (0.20-0.38); p = <0.001). VEGFA -2578 and MDM2 rs3730485 showed no significant association with DR. A-I-T (OR = 0.30 (0.20-0.44); p = <0.001) and C-D-T (OR = 0.33 (0.16-0.65); p = 0.002) haplotypes of rs699947-rs35569394-rs25648 polymorphisms showed decreased risk of DR.

CONCLUSIONS

I allele and II genotype of VEGFA -2549, CT genotype of VEGFA -7, and C-I-C and A-D-C haplotypes of rs699947-rs35569394-rs25648 polymorphisms were significantly associated with DR risk in a Northwest Indian population. This is the first study worldwide to report DR risk with VEGFA promoter variants together.

The Role of Genetic Polymorphisms in Diabetic Retinopathy: Narrative Review

Diabetic retinopathy (DR) is renowned as a leading cause of visual loss in working-age populations with its etiopathology influenced by the disturbance of biochemical metabolic pathways and genetic factors, including gene polymorphism. Metabolic pathways considered to have an impact on the development of the disease, as well as genes and polymorphisms that can affect the gene expression, modify the quantity and quality of the encoded product (protein), and significantly alter the metabolic pathway and its control, and thus cause changes in the functioning of metabolic pathways. In this article, the screening of chromosomes and the most important genes involved in the etiology of diabetic retinopathy is presented. The common databases with manuscripts published from January 2000 to June 2023 have been taken into consideration and chosen. This article indicates the role of specific genes in the development of diabetic retinopathy, as well as polymorphic changes within the indicated genes that may have an impact on exacerbating the symptoms of the disease. The collected data will allow for a broader look at the disease and help to select candidate genes that can become markers of the disease.

Associations of VEGF Polymorphisms With Retinopathy of Prematurity

Purpose

This study investigated the associations between vascular endothelial growth factor (VEGF) polymorphisms and retinopathy of prematurity (ROP) risk.

Methods

Infants born prematurely at any time from 2009 to 2018 were included. Five single-nucleotide polymorphisms (SNPs) of VEGF were analyzed using real-time PCR in all infants. Multivariate logistic regression was applied to model the associations between VEGF polymorphisms and ROP susceptibility, severity, and premature clinicopathologic characteristics.

Results

A total of 334 patients were included and categorized into three groups: those without ROP, those with mild ROP (i.e., ROP not requiring treatment), and those with severe ROP (i.e., ROP for whom treatment was indicated). Among the female patients with ROP, those with VEGF rs3025035 CT (3.231-fold; 95% confidence interval [CI], 1.238-8.431) and a combination of CT and TT genotypes (2.643-fold; 95% CI, 1.056-6.619) exhibited significantly higher risks of severe ROP compared with those with wild-type genotypes. Female ROP infants with VEGF rs3025010 C (TC + CC) alleles had a lower risk of ROP stage ≥3 (odds ratio [OR] = 0.406; 95% CI, 0.165-0.999) than those with TT homozygotes. ROP patients with the VEGF rs10434 A allele (GA + AA) exhibited higher risks of necrotizing enterocolitis (OR = 2.750; 95% CI, 1.119-6.759) and lower risk of bronchopulmonary dysplasia (OR = 0.390; 95% CI, 0.173-0.877) than those with GG homozygotes did.

Conclusions

VEGF polymorphisms affect ROP risks differently in male and female infants. In female infants, VEGF rs3025035 with T alleles may predict ROP severity, and VEGF rs3025010 with C alleles may protect against severe ROP.

Preeclampsia association of placental nucleotide variations in eNOS, VEGFA, and FLT-1 genes in Latin American pregnant women

INTRODUCTION

Preeclampsia is a leading cause of maternal and fetal morbidity in low- and middle-income countries, including those in Latin America. Placental vascular alterations are crucial in the pathophysiology of preeclampsia and few studies have evaluated nucleotide variations on genes associated with vascular regulation in the human placenta. This study aimed to evaluate whether placental nucleotide variations on eNOS, VEGFA, and FLT-1 genes are more frequently associated with preeclampsia in the Latin American population.

METHODS

This case-control study included placental tissue from 88 controls and 82 cases that were genotyped through Taqman probes for eNOS, VEGFA, and FLT-1 genes. The intergroup comparisons were analyzed with the Mann-Whitney U test. Genotype and allele frequencies were compared by the X² test. The association between the nucleotide variants with preeclampsia was evaluated through logistic regression analysis.

RESULTS

A significant association was observed for VEGFA SNV rs2010963 (OR 1.95; CI 95% 1.13-3.37), after adjusting for population substructure. The allele combination T, G, G, C, C, C (rs2070744, rs1799983, rs2010963, rs3025039, rs699947 and rs4769613 respectively), showed a negative association with preeclampsia (OR 0.08; CI 95% 0.01-0.93).

RESULTS

DISCUSSION

Placental SNV rs2010963 in the VEGFA gene was a risk factor for preeclampsia, while the allele combination T, G, G, C, C, C may represent potential protective factors for preeclampsia within Latin American women.

Association between Common Variants in VEGFA Gene and the Susceptibility of Primary Knee Osteoarthritis

OBJECTIVES

This study aimed to analyze the relationship between vascular endothelial growth factor A (VEGFA) gene polymorphisms, plasma VEGFA, and the susceptibility of knee osteoarthritis (OA).

DESIGN

A total of 404 subjects, 202 knee OA subjects and 202 healthy volunteers, were enrolled into the study. Four distinct polymorphisms of the VEGFA gene were evaluated using polymerase chain reaction-restriction fragment length polymorphism: -2578C/A (rs699947), -1154G/A (rs1570360), -634C/G (rs2010963), and +936C/T (rs3025039). Plasma VEGFA levels were analyzed using enzyme-linked immunosorbent assay.

RESULTS

The most common nucleotides in both knee OA subjects and healthy controls were CC for -2578C/A, GG for -1154G/A, CG for -634C/G, and CC for +936C/T in the VEGFA gene. Genotype distribution and allele frequencies of VEGFA -2578C/A, -1154G/A, -634C/G, and +936C/T single nucleotide polymorphisms did not differ between OA patients and the controls. Plasma VEGFA levels showed no difference between OA patients and the controls. In contrast, plasma VEGFA levels of -634C/C genotype were significantly higher in OA patients than in the controls (P = 0.035). According to the -2578A/A genotype, patients with early stage OA had a higher odds ratio than those with advanced stage OA (P = 0.023).

CONCLUSIONS

VEGFA -2578C/A (rs699947), -1154G/A (rs1570360), -634C/G (rs2010963), and +936C/T (rs3025039) polymorphisms may not be responsible for OA susceptibility in the Thai population. However, the OA patients with A/A genotype at the -2578C/A seemed to have a lower potential risk of developing severe OA than those with the C/A and C/C genotypes. These findings would help elucidate and facilitate a better understanding of the genetic fundamentals of OA.

The filarial and the antibiotics: Single or combination therapy using antibiotics for filariasis

Filarial infections caused by nematodes are one of the major neglected tropical diseases with public health concern. Although there is significant decrease in microfilariae (mf) prevalence following mass drug administration (IVM/DEC/ALB administration), this is transient, in that there is reported microfilaria repopulation 6-12 months after treatment. Wolbachia bacteria have been recommended as a novel target presenting antibiotic-based treatment for filarial disease. Potency of antibiotics against filarial diseases is undoubtful, however, the duration for treatment remains a hurdle yet to be overcome in filarial disease treatment.

VEGF gene polymorphism in complicated infective endocarditis

Introduction. Infective endocarditis (IE) is a bacterial disease with frequent pathogen localization on the heart valve apparatus. IE is characterized by rapid development of heart failure and frequent thromboembolic complications (TEC). IE features are accounted for by foreign pathogen nature and state of human immune system (IS). The imbalanced IS in infective endocarditis is manifested by impaired cytokine-mediated interactions. This confirms the rationality of studying cytokines to advance understanding of the pathogenesis for various conditions. Most cytokine genes are characterized by polymorphism and existing isoforms underlying disease predisposition. Genetic polymorphism of vascular endothelial growth factor A (VEGF-A) plays an important role in the induction of vasculogenesis and angiogenesis. The pathogenetic VEGF role in IE has not been thoroughly studied. Research objective analysis of polymorphic nucleotide sequence variants in the vascular endothelial growth factor gene, taking into account a relation with its serum concentration in patients with infective endocarditis. Materials and methods. 86 patients treated with verified diagnosis of infective endocarditis at the Scientific Research Institute Regional Clinical Hospital No. 1 of Krasnodar were divided into two clinical groups in accordance with the IE course: Group 1 IE with TEC (n = 44), group 2 IE without TEC (n = 42), and the control group consisted of 20 apparently healthy individuals. The concentration of serum VEGF-A (pg/mL) was measured by ELISA on day 1 of hospitalization. Genomic DNA was isolated from whole blood leukocytes and used to determine the frequency of genotypes of VEGF gene polymorphic variants. Results. Significant differences in the frequency distribution of VEGF-rs2010963 genotypes between patients with infective endocarditis and control group were revealed: G/G (OR = 0.25; p = 0.012) and G/C (OR = 4.28; p = 0.022), as well as differences between VEGF concentrations for various SNP-rs2010963 genotypes (p = 0.0001). A study of VEGF genotype frequency distribution between patients of clinical groups showed a significantly decreased frequency of the genotype G/G (rs2010963) in the IE group with TEC (OR = 0.21; p = 0.014) and increased frequency of G/C (OR = 4.72; p = 0.024) compared with the control group, whereas in patients with IE without TEC, significant (p = 0.0003) differences in serum concentrations of VEGF-rs2010963 were found in accordance with genotypes GG/CC (p = 0.01) and GG/GC (p = 0.003). Conclusion. The relationship between the VEGF genotypes (G/G and G/C of rs2010963 polymorphism) and related serum concentration among patients with IE was revealed. Carriers of the minor C allele (rs2010963) had higher serum VEGF levels. The results obtained complement and systematize current scientific data on the disease pathogenesis, as well as focus on the genetic determinant of the developing complications.

Emerging roles of growth factors in osteonecrosis of the femoral head

Osteonecrosis of the femoral head (ONFH) is a potentially disabling orthopedic condition that requires total hip arthroplasty in most late-stage cases. However, mechanisms underlying the development of ONFH remain unknown, and the therapeutic strategies remain limited. Growth factors play a crucial role in different physiological processes, including cell proliferation, invasion, metabolism, apoptosis, and stem cell differentiation. Recent studies have reported that polymorphisms of growth factor-related genes are involved in the pathogenesis of ONFH. Tissue and genetic engineering are attractive strategies for treating early-stage ONFH. In this review, we summarized dysregulated growth factor-related genes and their role in the occurrence and development of ONFH. In addition, we discussed their potential clinical applications in tissue and genetic engineering for the treatment of ONFH.

Molecular Polymorphisms of Vascular Endothelial Growth Factor Gene and Bronchopulmonary Dysplasia in Very Low Birth Weight Infants

Background

Bronchopulmonary dysplasia (BPD) is a chronic lung disease affecting primarily preterm and very low birth weight (VLBW) infants. Despite the advances in perinatal care, BPD remains a major clinical and costly complication in premature infants. The pathogenesis of BPD is complex and multifactorial. Prematurity, mechanical ventilation, oxidative stress, and inflammation are recognized as major interrelated contributing factors. Recently, some candidate genes involved in angiogenesis and alveolarization regulating mechanisms have been associated to BPD risk development. The aim of this study was to evaluate the role of vascular endothelial growth factor (VEGF) polymorphisms on BPD onset in VLBW newborns.

Methods

Eighty-two VLBW infants, without major anomalies, were consecutively enrolled: 33 developed BPD (BPD group) and 49 infants without BPD served as controls (control group). In all infants, two polymorphisms, respectively (VEGF receptor) VEGFR1-710 C/T and VEGF +936 C/T, were determined through salivary brush. Genomic DNA was extracted and purified from saliva samples by using the MasterAmp Buccal Swab DNA Extraction Kit (Tebu-bio, Milan, Italy).

Results

Significant statistic differences were found between BPD newborns and controls with regard to gestational age, birth weight, mechanical ventilation, duration of oxygen therapy, maternal preeclampsia, and chorioamnionitis. No differences were detected between genotypic and allelic levels regarding VEGFR1 and VEGF molecular polymorphisms.

Conclusions

Two single nucleotide polymorphisms within VEGF and VEGFR1 genes are not associated with BPD. Further researches are needed to reveal gene polymorphisms involved in vascular development as contributors to the onset of BPD.

Association study of HIF-1α rs11549465 and VEGF rs3025039 genetic variants with diabetic retinopathy in Egyptian patients: crosslinks with angiogenic, inflammatory, and anti-inflammatory markers

Background

Genetic factors are implicated in the progression of DR—a global cause of blindness. Hence, the current work investigated the association of HIF-1α rs11549465 and VEGF rs3025039 genetic variants with the different stages of retinopathy among T2DM Egyptian patients. The crosslinks of these variants were explored with angiogenesis (VEGF), inflammation (AGEP and VCAM-1), and anti-inflammation (CTRP3) markers. Two hundred eighty-eight subjects were recruited in this study: 72 served as controls and 216 were having T2DM and were divided into diabetics without retinopathy (DWR), diabetics with non-proliferative retinopathy (NPDR), and diabetics with proliferative retinopathy (PDR). The genetic variants were analyzed using PCR-RFLP and their associations with NPDR and PDR were statistically tested. The circulating levels of AGEP, VCAM-1, HIF-1α, VEGF, and CTRP3 were assayed followed by analyzing their associations statistically with the studied variants.

Results

Only HIF-1α rs11549465 genetic variant (recessive model) was significantly associated with the development of NPDR among T2DM patients (p < 0.025) with a significant correlation with the circulating HIF-1α level (p < 0.0001). However, this variant was not associated with PDR progression. Neither HIF-1α rs11549465 nor VEGF rs3025039 genetic variants were associated with the PDR progression. The circulating AGEP, VCAM-1, HIF-1α, and VEGF were significantly elevated (p < 0.0001) while the CTRP3 was significantly decreased (p < 0.0001) in NPDR and PDR groups. The HIF-1α rs11549465 CT and/or TT genotype carriers were significantly associated with AGEP and VCAM-1 levels in the NPDR group, while it showed a significant association with the CTRP3 level in the PDR group. The VEGF rs3025039 TT genotype carriers showed only a significant association with the CTRP3 level in the PDR group.

Conclusion

The significant association of HIF-1α rs11549465 other than VEGF rs3025039 with the initiation of NPDR in T2DM Egyptian patients might protect them from progression to the proliferative stage via elevating circulating HIF-1α. However, this protective role was not enough to prevent the development of NPDR because of enhancing angiogenesis and inflammation together with suppressing anti-inflammation. The non-significant association of HIF-1α rs11549465 with PDR among T2DM patients could not make this variant a risk factor for PDR progression.

Variants of SLC2A10 may be Linked to Poor Response to Metformin

Purpose

A study among Filipinos revealed that only 15% of patients with diabetes achieved glycemic control, and poor response to metformin could be one of the possible reasons. Recent studies demonstrate how genetic variations influence response to metformin. Hence, the present study aimed to determine genetic variants associated with poor response to metformin.

Methods

Using a candidate variant approach, 195 adult Filipino participants with newly diagnosed type 2 diabetes mellitus (T2DM) were enrolled in a case-control study. Genomic DNA from blood samples were collected. Allelic and genotypic associations of variants with poor response to metformin were determined using exact statistical methods.

Results

Several polymorphisms were nominally associated with poor response to metformin (P_uncorr < 0.05). The most notable is the association of multiple variants in the SLC2A10 gene—rs2425911, rs3092412, and rs2425904—with common additive genetic mode of inheritance. Other variants that have possible associations with poor drug response include rs340874 (PROX-AS1), rs815815 (CALM2), rs1333049 (CDKN2B-AS1), rs2010963 (VEGFA), rs1535435 and rs9494266 (AHI1), rs11128347 (PDZRN3), rs1805081 (NPC1), and rs13266634 (SLC30A8).

Conclusion

In Filipinos, a trend for the association for several variants was noted, with further observation that several mechanisms may be involved. The results may serve as pilot data for further validation of candidate variants for T2DM pharmacotherapy.

Investigation of multiple populations highlight VEGFA polymorphisms to modulate anterior cruciate ligament injury

Polymorphisms in VEGFA and KDR encoding proteins have been associated with anterior cruciate ligament (ACL) injury risk. We leveraged a collective sample from Sweden, Poland, and Australia to investigate the association of functional polymorphisms in VEGFA and KDR with susceptibility to ACL injury risk. Using a case-control genetic association approach, polymorphisms in VEGFA and KDR were genotyped and haplotypes inferred from 765 controls, and 912 cases clinically diagnosed with ACL rupture. For VEGFA, there was a significant overrepresentation of the rs2010963 CC genotype (p = 0.0001, false discovery rate [FDR]: p = 0.001, odds ratio [OR]: 2.16, 95% confidence interval [CI]: 1.47-3.19) in the combined ACL group (18%) compared to the combined control group (11%). The VEGFA (rs699947 C/A, rs1570360 G/A, rs2010963 G/C) A-A-G haplotype was significantly (p = 0.010, OR: 0.85, 95% CI: 0.69-1.05) underrepresented in the combined ACL group (23%) compared to the combined control group (28%). In addition, the A-G-G construct was significantly (p = 0.036, OR: 0.81, 95% CI: 0.64-1.02) underrepresented in the combined ACL group (12%) compared to the combined CON group (16%). Our findings support the association of the VEGFA rs2010963 CC genotype with increased risk and (ii) the VEGFA A-A-G haplotype with a reduced risk, and are in alignment with the a priori hypothesis. Collectively identifying a genetic interval within VEGFA to be implicated in ACL risk modulation and highlight further the importance of vascular regulation in ligament biology.

Investigation of Vascular Endothelial Growth Factor Polymorphisms on Risk, Metastasis, Laterality, and Prognosis of Colorectal Cancer in Turkish Subjects

Objectives: Tumor angiogenesis is known to support the spread and invasion of tumor cells, allow distant organ metastasis, resulting in worse prognosis and mortality. Since vascular endothelial growth factor-A (VEGF-A) is the major regulator of angiogenesis, in the present study, the associations of VEGF-A +405G>C and -460C>T polymorphisms with risk, primary tumor location, prognosis, and metastasis of colorectal cancer (CRC) were investigated in Turkish subjects. Material and Methods: A total of 153 subjects consisting of 74 controls and 79 CRC diagnosed patients were included in the study. VEGF-A +405G>C and -460C>T polymorphisms were analyzed using Agena MassARRAY platform. Results: VEGF +405GC+CC genotypes were found to be significantly associated with left colon cancer (unadjusted odds ratio [OR] = 5.208 confidence interval [95% CI]: 1.064-25.496, p = 0.04). VEGF -460TT and CT+TT genotypes were associated with reduced liver metastasis risk (OR = 0.080 95% CI: 0.009-0.689 p = 0.02 and OR = 0.191 95% CI: 0.039-0.925, p = 0.04, respectively). Patients with VEGF +405GG genotype showed longer progression-free survival as a response to bevacizumab treatment (Log rank = 6.92, p = 0.03). Conclusion: According to our results, VEGF +405G>C and -460C>T polymorphisms were found to be associated with CRC prognosis, sidedness, and metastasis. Our findings should be conducted in further studies.

A microRNA binding site polymorphism in the 3' UTR region of VEGF-A gene modifies colorectal cancer risk based on ethnicity: a meta-analysis

BACKGROUND

Vascular endothelial growth factor A (VEGF-A) plays an integral role in angiogenesis by contributing to growth, development, and metastasis of solid tumors. Recently, a single-nucleotide polymorphism +936C/T located in the VEGF-A 3' untranslated region (UTR) facilitated the susceptibility of colorectal cancer. The association between VEGF-A gene polymorphism +936C/T and colorectal cancer risk has been widely studied in the last decade, but presently, the results furnished remain enigmatic. Hence, the study aimed to investigate the association between VEGF-A +936C/T miRNA binding site polymorphism and the risk of developing colorectal cancer.

METHODS

This meta-analysis included 13 published case-control studies covering 3465 cases (colorectal cancer) and 3476 healthy controls. Publication bias was examined by means of Begg's funnel plots and Egger's regression tests. The quality of the studies included was evaluated using Newcastle-Ottawa scale. Subgroup analyses were performed in accordance to the various ethnicities of the study subjects and the study quality.

RESULTS

From the data obtained, it is implied that VEGF-A +936C/T polymorphism did not correlate with elevated colorectal cancer risk in all genetic models. But the results acquired from the subgroup analysis in over dominant model (CT vs. CC + TT: OR = 1.5047, 95% CI = 1.19-1.90) suggest that VEGF-A +936C/T polymorphism leads to the raise in the risk of developing CRC among the East Asian population. No association was observed in Caucasian and South Asian population.

CONCLUSIONS

Our results indicate that VEGF-A +936C/T polymorphism is not a risk factor for developing CRC in Caucasian and South Asian population. However, the East Asian population was related to an increased risk of developing colorectal cancer due to the presence of the minor allele.

Genetic Variants and Their Associations to Type 2 Diabetes Mellitus Complications in the United Arab Emirates

Aim

Type 2 Diabetes Mellitus (T2DM) is associated with microvascular complications, including diabetic retinopathy (DR), diabetic nephropathy (DNp), and diabetic peripheral neuropathy (DPN). In this study, we investigated genetic variations and Single Nucleotide Polymorphisms (SNPs) associated with DR, DNp, DPN and their combinations among T2DM patients of Arab origin from the United Arab Emirates, to establish the role of genes in the progression of microvascular diabetes complications.

Methods

A total of 158 Emirati patients with T2DM were recruited in this study. The study population was divided into 8 groups based on the presence of single, dual, or all three complications. SNPs were selected for association analyses through a search of publicly available databases, specifically genome-wide association study (GWAS) catalog, infinome genome interpretation platform, and GWAS Central database. A multivariate logistic regression analysis and association test were performed to evaluate the association between 83 SNPs and DR, DNp, DPN, and their combinations.

Results

Eighty-three SNPs were identified as being associated with T2DM and 18 SNPs had significant associations to one or more diabetes complications. The most strongly significant association for DR was rs3024997 SNP in the VEGFA gene. The top-ranked SNP for DPN was rs4496877 in the NOS3 gene. A trend towards association was detected at rs833068 and rs3024998 in the VEGFA gene with DR and rs743507 and rs1808593 in the NOS3 gene with DNp. For dual complications, the rs833061, rs833068 and rs3024997 in the VEGFA gene and the rs4149263 SNP in the ABCA1 gene were also with borderline association with DR/DNp and DPN/DNp, respectively. Diabetic with all of the complications was significantly associated with rs2230806 in the ABCA1 gene. In addition, the highly associated SNPs rs3024997 of the VEGFA gene and rs4496877 of the NOS3 gene were linked to DR and DPN after adjusting for the effects of other associated markers, respectively.

Conclusions

The present study reports associations of different genetic polymorphisms with microvascular complications and their combinations in Emirati T2DM patients, reporting new associations, and corroborating previous findings. Of interest is that some SNPs/genes were only present if multiple comorbidities were present and not associated with any single complication.

A novel personalised treatment approach for psoriasis: anti-VEGF-A therapy

Chronic plaque psoriasis is an inflammatory skin disease in which genetic predisposition along with environmental factors lead to the development of the disease, which affects 2% of the UK’s population and is associated with extracutaneous morbidities and a reduced quality of life. A complex crosstalk between innate and adaptive immunity, the epithelia and the vasculature maintain the inflammatory milieu in psoriasis. Despite the development of promising treatment strategies, mostly targeting the immune system, treatments fail to fulfil every patient’s goals. Vascular endothelial growth factor‐A (VEGF‐A) mediates angiogenesis and is upregulated in the plaques and plasma of patients with psoriasis. Transgenic expression of VEGF‐A in experimental models led to the development of skin lesions that share many psoriasis features. Targeting VEGF‐A in in vivo models of psoriasis‐like inflammation resulted in disease clearance. Anti‐angiogenesis treatments are widely used for cancer and eye disease and there are clinical reports of patients treated with VEGF‐A inhibitors who have experienced Psoriasis Area and Severity Index improvement. Existing psoriasis treatments downregulate VEGF‐A and angiogenesis as part of their therapeutic effect. Pharmacogenetics studies suggest the existence of different genetic signatures within patients with psoriasis that correspond with different treatment responsiveness and disease severity. There is a subset of patients with psoriasis with an increased predisposition to produce high levels of VEGF‐A, who may be most likely to benefit from anti‐VEGF‐A therapy, offering an opportunity to personalize treatment in psoriasis. Anti‐VEGF‐A therapies may offer an alternative to existing anticytokine strategies or be complementary to standard treatments for the management of psoriasis.

Clinical Implications of MiR128, Angiotensin I Converting Enzyme and Vascular Endothelial Growth Factor Gene Abnormalities and Their Association with T2D

Type 2 DM (T2D) results from the interaction of the genetic and environmental risk factors. Vascular endothelial growth factor (VEGF), angiotensin I-converting enzyme (ACE), and MicroRNAs (MiRNAs) are involved in important physiological processes. Gene variations in VEGF, ACE and MiRNA genes are associated with diseases. In this study we investigated the associations of the VEGF-2578 C/A (rs699947), VEGF-2549 insertion/deletion (I/D), and ACE I/D rs4646994 and Mir128a (rs11888095) gene variations with T2D using the amplification refractory mutation system PCR (ARMS-PCR) and mutation specific PCR (MSP). We screened 122 T2D cases and 126 healthy controls (HCs) for the rs699947, and 133 T2D cases and 133 HCs for the VEGF I/D polymorphism. For the ACE I/D we screened 152 cases and 150 HCs, and we screened 129 cases and 112 HCs for the Mir128a (rs11888095). The results showed that the CA genotype of the VEGF rs699947 and D allele of the VEGF I/D polymorphisms were associated with T2D with OR =2.01, p-value = 0.011, and OR = 2.42, p-value = 0.010, respectively. The result indicated the D allele of the ACE ID was protective against T2D with OR = 0.10, p-value = 0.0001, whereas the TC genotype and the T allele of the Mir128a (rs11888095) were associated with increased risk to T2D with OR = 3.16, p-value = 0.0001, and OR = 1.68, p-value = 0.01, respectively. We conclude that the VEGF (rs699947), VEGF I/D and Mir128a (rs11888095) are potential risk loci for T2D, and that the D allele of the ACE ID polymorphism may be protective against T2D. These results help in identification and stratification for the individuals that at risk for T2D. However, future well-designed studies in different populations and with larger sample sizes are required. Moreover, studies to examine the effects of these polymorphisms on VEGF and ACE proteins are recommended.

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 (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.

The association of VEGF rs833061 and rs2010963 polymorphisms with susceptibility to colorectal cancer in an Iranian population

Vascular endothelial growth factor (VEGF) is one of the most important regulators of angiogenesis. Several single nucleotide polymorphisms (SNPs) are associated with the VEGF overexpression and tumor progression in several cancers. This study aimed to determine the association of VEGF rs833061 and rs2010963 polymorphism and their haplotypes with susceptibility to colorectal cancer (CRC) in the Iranian population. A total of 284 colorectal cancer patients (37.3% women, 62.7% men) were enrolled in this study. Healthy controls without evidence of cancer history or family cancer predispositions were frequency-matched to the cases by sex and age (± 5 years). Genotyping was performed by the Sequenom mass ARRAY method and the genotype distribution and risk estimate were analyzed by SPSS software. The correlation between the genotypes and clinicopathological parameters (Dukes stage, phenotype, location, differentiation, and tumor size) among colorectal cancer patients were investigated. We found a significant relationship, between rs833061T/C genotype and their TG haplotype with the age of diagnosis < 60; (p = 0.012, p = 0.014) and rs2010963G/C genotype with female gender and TG haplotype with third and fourth tumor stage and tumor location (p = 0.04and p = 0.047). This study showed that rs833061T/C genotype and TG haplotype increase the susceptibility to colon cancer in the Iranian population. This susceptibility has a significant relationship with the age of diagnosis and different stages of the tumor.

Association of VEGF haplotypes with breast cancer risk in North-West Indians

BACKGROUND

Angiogenesis is a complex and coordinated process regulated by different growth factors and is one of the hallmark features of cancer. VEGF is one of the most important endothelial cell mitogen and has a critical role in normal physiological and tumor angiogenesis. The objective of this study was to investigate the potential association of haplotypes of six VEGF polymorphisms with breast cancer risk in North-West Indians.

METHODS

Samples of 250 breast cancer patients and 250 age and sex matched controls were genotyped for VEGF -2578C/A, -2549I/D, -460T/C, +405C/G, -7C/T and +936C/T polymorphisms. Haplotypes were generated to determine the better contribution of VEGF polymorphisms to breast cancer risk.

RESULTS

Haplotypes CDTCCC (OR = 0.56, 95%CI, 0.38-0.81; p = 0.003) and CDTGCC (OR = 0.63, 95%CI, 0.44-0.92; p = 0.018) of VEGF -2578C/A, -2549I/D, -460T/C, +405C/G, -7C/T and +936C/T polymorphisms were significantly associated with decreased risk of breast cancer. CDTCCC haplotype was also significantly associated with reduced risk of breast cancer in pre and post menopausal as well as both obese and non obese patients. Haplotype CDTGCC was marginally associated (p = 0.07) with reduced risk of breast cancer in non-obese patients as compared with non-obese controls where as haplotype AICGTC was marginally associated (p = 0.09) with reduced risk of breast cancer in obese patients when compared with non-obese patients. The CDTGCC haplotype was significantly associated with increased risk of breast cancer in premenopausal obese patients (OR = 1.98, 95%CI, 1.10-3.56; p = 0.02).

CONCLUSIONS

Our data indicated that CDTCCC and CDTGCC haplotypes of VEGF -2578C/A, -2549I/D, -460T/C, +405C/G, -7C/T and +936C/T polymorphisms were significantly associated with breast cancer risk in North-West Indians. Further studies on multiethnic groups with larger sample size are required to confirm our results.

Implications of VEGF gene sequence variations and its expression in recurrent pregnancy loss

RESEARCH QUESTION

What is the association between VEGF gene sequence variants and its mRNA expression in recurrent pregnancy loss (RPL)? Vascular endothelial growth factor (VEGF) has a prominent role in pregnancy and affects pregnancy outcome. The association of VEGF gene 1154G>A, 634G>C and 583C>T polymorphic variations with cases of RPL and full-term fertile women as controls was investigated.

DESIGN

Two hundred women with RPL and 240 women healthy controls were included. The restriction fragment length polymorphism method was used for genotyping and quantitative real-time polymerase chain reaction was used for analysis of mRNA expression.

RESULTS

In VEGF 1154G>A, significant differences were found in homozygous AA genotype between case and control participants. The variant allele A frequency was significantly more abundant in RPL cases (0.41) than controls (0.19) (P < 0.0001). Only RPL cases with the multi-generation family history of miscarriages and those without any history showed significant differences of combined genotype GA+AA (P < 0.0001). In VEGF 634 G>C, CC genotype and allele C showed significantly increased frequency in RPL cases compared with healthy controls (P < 0.0001). The association between VEGF-1154 G>A SNP and VEGF-A mRNA expression levels was significant in RPL cases (P = 0.004). The heterozygous genotype GA was significantly (P = 0.03) associated with upregulation and downregulation of VEGF mRNA, whereas the homozygous variant genotype AA only leads to low expression levels of VEGF mRNA in patients with RPL.

CONCLUSIONS

All the variants of VEGF play a vital role in an increased susceptibility to RPL. Also, VEGF-1154, AA genotypes are associated with its altered low mRNA expression in women with RPL and seem to affect pregnancy outcome.

An Investigation of the Association Between Vascular Endothelial Growth Factor +405 G/C Polymorphism and Acute Liver Transplant Rejection in Iranian Liver Transplant Recipients

OBJECTIVES

Vascular endothelial growth factor is an endothelial-specific growth factor that promotes endothelial cell proliferation, differentiation, and survival; mediates endothelium-dependent vasodilatation; induces microvascular hyperpermeability; and participates in interstitial matrix remodeling. The aim of the present study was to investigate the association between +405 G/C polymorphism of vascular endothelial growth factor and the risk of liver rejection in liver transplant recipients.

MATERIALS AND METHODS

The present study included 124 patients with liver disease that led to liver transplant. There were 22 patients who experienced histologically proven acute liver rejection, and the other 102 patients showed no rejection. Both groups were matched for sex and age. The VEGF+405 G/C polymorphism was evaluated by the polymerase chain reaction-restriction fragment-length polymorphism method.

RESULTS

Our analyses showed no significant relationships between genotypes and alleles of +405 G/C and risk of acute liver transplant rejection.

CONCLUSIONS

Our report indicated that there was no association between the carrier states of +405 G/C gene polymorphism of vascular endothelial growth factor and acute rejection or nonrejection of liver transplant.

Polymorphisms of vascular endothelial growth factor and recurrent implantation failure: a systematic review and meta-analysis

PURPOSE

To investigate the associations between polymorphisms of vascular endothelial growth factor (VEGF) with recurrent implantation failure (RIF).

METHODS

We performed the systematic review and meta-analysis by searching databases of PubMed, EMBASE, OVID, and CNKI (China National Knowledge Infrastructure) for studies that evaluated the associations between VEGF polymorphisms with RIF. Meta-analysis was performed if the polymorphism was studied by more than two case-control studies. Data were analyzed using R software. Odds ratios (ORs) with 95% confidence intervals (CIs) were reported to assess the associations.

RESULTS

Nine VEGF polymorphisms (-1154G > A, -460T > C, +405G > C, -7C > T, -634C > G, -2578C > A, +936C > T, 5C > T, -583C > T) were systematically reviewed. Meta-analysis was performed on VEGF -1154 G > A polymorphism. Three case-control studies consisted of 683 women were included in the quantitative meta-analysis (305 RIF patients and 378 controls). Results showed that VEGF -1154A allele was significantly associated with RIF (OR 1.39, 95% CI 1.08-1.78, P-value = 0.01). The dominant genetic model showed that VEGF 1154AA plus VEGF 1154AG genotypes were more frequent in RIF patients than VEGF 1154GG genotype (OR 1.56, 95% CI 1.10-2.20, P-value = 0.01). However, the result under the recessive genetic model showed no significant difference (OR 1.67, 95% CI 0.92-3.03, P-value = 0.09).

CONCLUSION

VEGF -1154A allele may serve as one of the predisposing factors of RIF. Women with VEGF 1154 AA/GA genotypes were at higher risk of RIF. However, we should consider the haplotype effect of VEGF polymorphisms in future studies.

FINDER: an automated software package to annotate eukaryotic genes from RNA-Seq data and associated protein sequences

BACKGROUND

Gene annotation in eukaryotes is a non-trivial task that requires meticulous analysis of accumulated transcript data. Challenges include transcriptionally active regions of the genome that contain overlapping genes, genes that produce numerous transcripts, transposable elements and numerous diverse sequence repeats. Currently available gene annotation software applications depend on pre-constructed full-length gene sequence assemblies which are not guaranteed to be error-free. The origins of these sequences are often uncertain, making it difficult to identify and rectify errors in them. This hinders the creation of an accurate and holistic representation of the transcriptomic landscape across multiple tissue types and experimental conditions. Therefore, to gauge the extent of diversity in gene structures, a comprehensive analysis of genome-wide expression data is imperative.

RESULTS

We present FINDER, a fully automated computational tool that optimizes the entire process of annotating genes and transcript structures. Unlike current state-of-the-art pipelines, FINDER automates the RNA-Seq pre-processing step by working directly with raw sequence reads and optimizes gene prediction from BRAKER2 by supplementing these reads with associated proteins. The FINDER pipeline (1) reports transcripts and recognizes genes that are expressed under specific conditions, (2) generates all possible alternatively spliced transcripts from expressed RNA-Seq data, (3) analyzes read coverage patterns to modify existing transcript models and create new ones, and (4) scores genes as high- or low-confidence based on the available evidence across multiple datasets. We demonstrate the ability of FINDER to automatically annotate a diverse pool of genomes from eight species.

CONCLUSIONS

FINDER takes a completely automated approach to annotate genes directly from raw expression data. It is capable of processing eukaryotic genomes of all sizes and requires no manual supervision-ideal for bench researchers with limited experience in handling computational tools.

Effect of X-rays on transcript expression of rat brain microvascular endothelial cells: role of calcium signaling in X-ray-induced endothelium damage

Radiation-induced brain edema is a serious adverse effect of radiotherapy. Although there are many causes of radiation-induced brain edema, the pathogenesis is not clear and clinical treatment is not ideal. Therefore, knowing the differential expression of the brain microvascular endothelial cell (BMEC) transcriptome after brain radiotherapy may shed light on the pathogenesis of radiation-induced brain edema. The present study used RNA-Seq technique to identify 383 BMEC transcripts differentially expressed (many 2-fold or higher; P < 0.05) between control and X-ray–treated primary cultured rat BMECs. Compared with controls, X-ray–treated BMECs had 183 significantly up-regulated transcripts and 200 significantly down-regulated transcripts. The differentially expressed genes were associated with the biological processes of the cell cycle, apoptosis, vascular permeability, and extracellular junctions. The functional changes identified in the X-ray–treated BMECs included Ca²⁺ signaling, phosphoinositide 3-kinase–Akt signaling, and methionine degradation. These results indicated that transcript expression was substantially affected by radiation exposure and the proteins encoded by these differentially expressed genes may play a significant role in radiotherapy-induced brain edema. Our findings provide additional insight into the molecular mechanisms of radiation-induced brain edema and may be helpful in the development of clinical treatment of this adverse reaction to radiotherapy.

Associations between Vascular Endothelial Growth Factor Gene Polymorphisms and Different Types of Diabetic Retinopathy Susceptibility: A Systematic Review and Meta-Analysis

BACKGROUND

Vascular endothelial growth factor (VEGF) gene polymorphisms have been shown to be associated with the risk of diabetic retinopathy (DR), but the results were inconsistent. The aim of this study was to systematically assess the associations between VEGF gene polymorphisms and different types of DR (nonproliferative DR and proliferative DR).

METHODS

Electronic databases PubMed, Embase, Web of Science, CNKI, and WANFANG DATA were searched for articles on the associations between VEGF gene polymorphisms and different types of DR up to November 6, 2019. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and subgroup analyses were conducted by ethnicity. Sensitivity analysis was conducted to assess the stability of the results. Publication bias was assessed by using the Egger regression asymmetry test and visualization of funnel plots. A systematic review was conducted for polymorphisms with a high degree of heterogeneity (I ² > 75%) or studied in only one study.

RESULTS

A total of 13 and 18 studies analyzed the associations between VEGF SNPs and nonproliferative DR (NPDR) as well as proliferative DR (PDR), respectively. There were significant associations between rs2010963 and NPDR in Asian (dominant model: OR = 1.29, 95%CI = 1.04 - 1.60); and rs2010963 is associated with PDR in total population (dominant model: OR = 1.20, 95%CI = 1.03 - 1.41), either Asian (recessive model: OR = 1.57, 95%CI = 1.04 - 2.35) or Caucasian (recessive model: OR = 1.83, 95%CI = 1.28 - 2.63). Rs833061 is associated with PDR in Asian (recessive model: OR = 1.58, 95%CI = 1.11 - 2.26). Rs699947 is associated with NPDR in the total population (dominant model: OR = 2.04, 95%CI = 1.30 - 3.21) and associated with PDR in Asian (dominant model: OR = 1.72, 95%CI = 1.05 - 2.84).

CONCLUSIONS

Rs2010963, rs833061, and rs699947 are associated with NPDR or PDR, which may be involved in the occurrence and development of DR.

The 100 Most Cited Articles in Ophthalmology in Asia

PURPOSE

The aim of this study was to review the top 100 most-cited articles in ophthalmology in Asia since 1970.

METHODS

The Scopus database was used to identify the top 100 most-cited ophthalmology articles published in ophthalmology (T100-Eye) and nonophthalmology (T100-General) journals.

RESULTS

The T100-Eye articles were published between 1982 and 2015, and T100-General from 1982 to 2017. T100-Eye had higher citations [median (range) = 317 (249-1326)] than T100-General [158 (105-2628)], but T100-General were published in journals with higher impact factor (IF) than T100-Eye (median IF= 5.5 vs 4.4) and produced more landmark papers (3 vs 1 articles that were cited >1000 times). Fifty-five % of T100-Eye were published in 3 journals: Ophthalmology (n = 22), Investigative Ophthalmology and Visual Science (n = 17), and American Journal of Ophthalmology (n = 16). T100-Eye had 88 original research articles and 12 reviews, whereas T100-General had 84 original research and 16 reviews. The most-frequent studied disease categories were myopia (n = 16) and age-related macular degeneration (n = 15) in T100-Eye and diabetic retinopathy (n = 24) and glaucoma (n = 16) in T100-General. Japan and Singapore contributed most to T100-Eye (n = 42, n = 17) and T100-General (n = 36, n = 26) articles. More than 80% and 95% of first and last authors were male in both lists. Emerging research topics were optical coherence tomography in T100-Eye and artificial intelligence in T100-General.

CONCLUSIONS

Our citation analysis reveals differences in the focus of research topics of top-cited ophthalmology articles published in ophthalmology and nonophthalmology journals in Asia. It highlights that certain eye diseases are studied more in Asia and shows the contribution of specific countries to highly cited publications in ophthalmology research in Asia.

100 most-cited articles on diabetic retinopathy

Diabetic retinopathy (DR) research has had significant advancements over the past decades. We analysed the impact and characteristics of the top 100 (T100) most-cited articles in DR research. The Scopus database was searched for articles published from 1960 to June 2020 by two independent investigators. The T100 DR articles were published between 1961 and 2017 with median citations of 503 (range: 306-20 100); 84% were published after 1990. More than half (59%) were published in general medical/diabetes journals while 37% in ophthalmology journals. The top six journals contributed to 56% of the T100: Ophthalmology (n=13), Archives of Ophthalmology (n=12), Diabetes (n=9), New England Journal of Medicine (n=8), Journal of the American Medical Association (n=7) and The Lancet (n=7). Although observational studies were most popular (33%), randomised controlled trials (RCTs, 24%) published in journals with higher impact factor (IF) and citations (median IF and citations=7.113, 503 vs 21.437, 696.5, both p-value<0.05). 33 of the T100 were cited by several international DR clinical guidelines. The USA contributed to 63% of T100, but 18% of articles published after 2000 came from Asia. More than 80% of both first and last authors were men. Artificial intelligence (AI) to screen for DR ranked 14th and 99th despite recent publications in 2016 and 2017, respectively. To conclude, our T100 analysis showed that RCTs were most-cited and more articles were published in non-ophthalmology than ophthalmology journals. It highlights the impact the T100 DR has in shaping guidelines used to date in DR management, identifies AI for DR screening as an emerging area and shows a contemporary rise of Asian contribution in DR research.

Association of VEGF Gene Family Variants with Central Macular Thickness and Visual Acuity after Aflibercept Short-Term Treatment in Diabetic Patients: A Pilot Study

INTRODUCTION

Diabetic retinopathy (DR) is one of the major vision-threatening causes worldwide. Searching for an individualized therapeutic strategy to prevent its progress is challenging.

OBJECTIVE

This work aimed to investigate the association of angiogenesis-inducer vascular endothelial growth factor (VEGF) gene family and related receptor variants (rs833069, rs12366035, rs7664413, rs7993418, and rs2305948) with susceptibility of DR and the response to 1 dose of aflibercept treatment in type 2 diabetes mellitus (T2DM).

METHODS

Consecutive eligible patients with T2DM (n = 125) and 110 unrelated controls were enrolled in this preliminary prospective case-controlled study. Genotyping was identified using TaqMan real-time PCR. Adjusted odds ratio (OR) with 95% confidence interval (CI) was applied to assess the strength of the association with the clinical/ophthalmological characteristics and early response to intravitreal aflibercept treatment in terms of improved visual acuity (BCVA) and central macular thickness (CMT).

RESULTS

We found that both VEGFB rs12366035 and VEGFC rs7664413 conferred higher risk for DR progression under allelic (OR [95% CI]: 1.71 [1.07-2.74]), homozygote comparison (3.55 [1.32-9.57]), and recessive (3.77 [1.43-9.93]) models for the former and under allelic (2.09 [1.25-3.490, homozygote comparison (2.76 [1.02-7.45]), and recessive (2.62 [0.98-6.98] models for the latter. In contrast, VEGFR1 rs7993418 conferred protection against DR under heterozygote comparison and dominant models. The rs12366035*T/T genotype showed the worst pretreatment BCVA score (0.35 ± 0.24) compared to other corresponding genotypes (0.66 ± 0.26 in C/T and 0.54 ± 0.25 in C/C carriers) (p = 0.008). Meanwhile, patients with rs7993418*G/G of VEGFR1 exhibited a significant reduction in CMT after aflibercept injection (12.26 ± 35.43 µ in G/G vs. 3.57 ± 8.74 µ in A/A) (p = 0.037).

CONCLUSIONS

Polymorphisms of the studied VEGF/receptors could be considered as genetic risk factors of DM/DR development and could play an important role in aflibercept early response for DR patients in the study population.

Association of Genetic Variants in ANGPT/TEK and VEGF/VEGFR with Progression and Survival in Head and Neck Squamous Cell Carcinoma Treated with Radiotherapy or Radiochemotherapy

Angiogenesis is essential for growth, progression, and metastasis of solid tumors. Vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) and angiopoietin (ANGPT)/ tyrosine kinase endothelial (TEK) signaling plays an important role in regulating angiogenesis. Very little is known about the effects of single-nucleotide polymorphisms (SNPs) in angiogenesis-related genes on treatment outcome in head and neck squamous cell carcinoma (HNSCC). Therefore, we evaluated the association between SNPs in ANGPT1, ANGPT2, TEK, VEGF, VEGFR1, and VEGFR2 genes and five clinical endpoints in 422 HNSCC patients receiving radiotherapy alone or combined with chemotherapy. Multivariate analysis showed an association of ANGPT2 rs3739391, rs3020221 and TEK rs639225 with overall survival, and VEGF rs2010963 with overall and metastasis-free survival. VEGFR2 rs1870377 and VEGF rs699947 affected local recurrence-free survival in all patients. In the combination treatment subgroup, rs699947 predicted local, nodal, and loco-regional recurrence-free survival, whereas VEGFR2 rs2071559 showed an association with nodal recurrence-free survival. However, these associations were not statistically significant after multiple testing correction. Moreover, a strong cumulative effect of SNPs was observed that survived this adjustment. These SNPs and their combinations were independent risk factors for specific endpoints. Our data suggest that certain germline variants in ANGPT2/TEK and VEGF/VEGFR2 axes may have predictive and prognostic potential in HNSCC treated with radiation or chemoradiation.

Epigenome-wide association study in healthy individuals identifies significant associations with DNA methylation and PBMC extract VEGF-A concentration

INTRODUCTION

Vascular endothelial growth factor A (VEGF-A) is a chemokine that induces proliferation and migration of vascular endothelial cells and is essential for both physiological and pathological angiogenesis. It is known for its high heritability (> 60%) and involvement in most common morbidities, which makes it a potentially interesting biomarker. Large GWAS studies have already assessed polymorphisms related to VEGF-A. However, no previous research has provided epigenome-wide insight in regulation of VEGF-A.

METHODS

VEGF-A concentrations of healthy participants from the STANISLAS Family Study (n = 201) were comprehensively assessed for association with DNA methylation. Genome-wide DNA methylation profiles were determined in whole blood DNA using the 450K Infinium BeadChip Array (Illumina). VEGF-A concentration in PBMC extracts was detected using a high-sensitivity multiplex Cytokine Array (Randox Laboratories, UK).

RESULTS

Epigenome-wide association analysis identified 41 methylation sites significantly associated with VEGF-A concentrations derived from PBMC extracts. Twenty CpG sites within 13 chromosomes reached Holm-Bonferroni significance. Significant values ranged from P = 1.08 × 10-7 to P = 5.64 × 10-15.

CONCLUSION

This study exposed twenty significant CpG sites linking DNA methylation to VEGF-A concentration. Methylation detected in promoter regions, such as TPX2 and HAS-1, could explain previously reported associations with the VEGFA gene. Methylation may also help in the understanding of the regulatory mechanisms of other genes located in the vicinity of detected CpG sites.

Gene polymorphisms of VEGF and VEGFR2 are associated with the severity of Hashimoto's disease and the intractability of Graves' disease, respectively

Vascular endothelial growth factor (VEGF) is one of main regulators of angiogenesis that functions by binding to its receptors, including VEGF receptor (VEGFR) 2. There are few data available regarding the association between VEGF and VEGFR polymorphisms and the susceptibility to and prognosis of autoimmune thyroid diseases (AITDs). To elucidate this association, we genotyped four functional VEGF and two VEGFR2 polymorphisms and measured serum VEGF levels. In the four functional VEGF polymorphisms, the frequencies of the I carrier and I allele of VEGF -2549 I/D, which has lower activity, were higher in patients with severe HD than in those with mild HD. In the two functional VEGFR2 polymorphisms, the frequency of the rs2071559 CC genotype, which has higher activity, was higher in patients with intractable GD than in controls, and the proportion of GD patients with larger goiters was higher in those with the CC genotype. Moreover, the frequency of the rs1870377 TT genotype with higher activity was higher in patients with intractable GD than in those with GD in remission. Combinations of VEGF and VEGFR2 polymorphisms with stronger interactions were associated with the intractability of GD. Serum VEGF levels were higher in HD and AITD patients than those in controls. In conclusion, VEGF polymorphisms with lower activity were associated with the severity of HD, while VEGFR2 polymorphisms and the combinations of VEGF and VEGFR2 polymorphisms, which have stronger interactions, were associated with the intractability of GD. VEGF and VEGFR2 polymorphisms were associated with HD severity and GD intractability, respectively.

Diabetic Retinopathy and BDNF: A Review on Its Molecular Basis and Clinical Applications

Impairment of neuroprotection and vasculopathy are the main reasons for the progression of diabetic retinopathy. In this review, we decided to illustrate the molecular and clinical aspects of diabetic retinal neuro-vasculopathy. We searched the Web of Science, PubMed, and Scopus databases with these keywords: “brain-derived neurotrophic factor” and “vascular endothelial growth factor” and/or “diabetic retinopathy.” The most relevant in vitro and clinical trial studies were then extracted for final interpretation. Brain-derived neurotrophic factor and the vascular endothelial growth factor have pivotal roles in the pathogenesis of diabetic retinopathy. They have neuroprotective effects on the retina. However, there are controversial results on the relation between these two factors. Reviewing available articles, we have concluded that various concentrations of these molecules at different stages of retinopathy may exert different effects. Optimal doses of the brain-derived neurotrophic factor at the early stages of retinopathy may have a neuroprotective effect. In contrast, higher concentrations of brain-derived neurotrophic factor might induce inflammatory responses. Damage to the retinal cells due to metabolic alterations associated with diabetes and its consequence vasculopathy may also lead to changes in the ocular microenvironment and cytokines. Changes in cytokines result in the modification of neural cell receptors and the overproduction of vascular endothelial growth factor. It seems that controlling the optimal levels of neuroprotective molecules in the retinal tissue is the main step to halter diabetic retinopathy.

Pharmacogenetics of medication-related osteonecrosis of the jaw: a systematic review and meta-analysis

Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication that can develop in patients treated with anti-resorptive drugs. Although the pathogenesis of MRONJ is still unclear, genetic factors have a demonstrated important role. Thus, the aim of this study was to perform a systematic review on the pharmacogenetics of MRONJ. Studies published until March 2019 were retrieved from eight databases and were selected by two independent reviewers. Evidence on several genetic polymorphisms was summarized and a meta-analysis was conducted when possible. Fourteen studies involving 1515 participants were eligible for systematic review. For CYP2C8 rs1934951, no significant difference was observed between the MRONJ and non-MRONJ groups (odds ratio (OR) 2.04, 95% confidence interval (CI) 0.88-4.73, P=0.09). However, a subgroup analysis based on only multiple myeloma status showed a positive association (OR 3.64, 95% CI 1.29-10.30, P=0.01). PPARG rs1152003 was not differently distributed between groups (OR 0.25, 95% CI 0.01-9.92, P=0.46). Also, VEGF rs3025039 was found to be correlated with the occurrence of MRONJ (OR 0.35, 95% CI 0.15-0.82, P=0.02). CYP2C8 rs1934951 (in multiple myeloma patients) and VEGF rs3025039 are associated with the development of MRONJ in patients treated with bisphosphonates. The results are promising and call for new trials with a larger sample to further explore this growing field.

Association of rs699947 (-2578 C/A) and rs2010963 (-634 G/C) Single Nucleotide Polymorphisms of the VEGF Gene, VEGF-A and Leptin Serum Level, and Cardiovascular Risk in Patients with Excess Body Mass: A Case-Control Study

Background: Two single nucleotide polymorphisms (SNPs) of the VEGF gene, rs699947 and rs2010963, are responsible for differentiated gene expression. A mutual dependence between VEGF and leptin serum level has been observed. This study investigated the associations between the rs699947 and rs2010963 SNPs of VEGF gene, VEGF-A, and leptin serum concentrations, and cardiometabolic risk of body mass excess. Methods: In this case–control study, 212 subjects with excess body mass and 145 normal-weight controls gave blood samples and underwent anthropometric and pulse wave analysis. Genotyping of VEGF gene was carried out to analyze the rs699947 (−2578 C/A) and rs2010963 (−634 G/C) SNPs. (ClinicalTrials.gov ID: NCT04077554). Results: This study showed a significant positive correlation between serum levels of VEGF-A and leptin in individuals with excess body mass possessing the CC genotype of the rs699947 variant of the VEGF gene. It has been registered that an increase in VEGF-A serum level correlates with an increase in arterial stiffness in excess body mass patients harboring AA genotype of the rs699947 (−2578 C/A) variant of the VEGF gene. No differences in VEGF-A and leptin serum concentrations were noted between particular genotypes. Conclusions: The CC genotype of the rs699947 variant of the VEGF gene promotes a positive interdependency between leptin and VEGF-A serum levels in subjects with excess body mass.

Association of vascular endothelial growth factor A polymorphisms and aberrant expression of connexin 43 and VEGFA with idiopathic recurrent spontaneous miscarriage

AIM

Idiopathic recurrent spontaneous miscarriage (IRSM) is one of the pregnancy outcomes that affects 1-2% of women trying to conceive. Specific genotype or aberrant expression of vascular endothelial growth factor A (VEGFA) and connexin 43 (Cx43) as two important genes for embryonic development are deemed to increase the risk of IRSM.

METHODS

To investigate any possible association of VEGFA polymorphisms and aberrant expression of Cx43 and VEGFA with IRSM, we carried out a case-control study including embryo chorionic villus tissues of 100 pregnant women with IRSM and 100 embryo chorionic villus tissues of healthy pregnant women without history of miscarriage. Restriction fragment length polymorphism was used for genotyping of rs699947 (-2578C/A) and rs2010963 (-634G/C) polymorphisms in VEGFA. Besides, quantitative real-time PCR was performed for VEGFA and Cx43 expression analysis.

RESULTS

The results showed that the frequency of -634G/C and C/C genotypes was significantly higher in aborted fetuses (P = 0.001 and P < 0.001, respectively) compared to the control group's. However, the frequency of -2578C/A genotypes was not significantly different between the cases and controls. Moreover, a significant higher expression of VEGF (P = 0.0005) and Cx43 (P = 0.0011) was observed in chorionic villus tissues of women with IRSM.

CONCLUSION

The finding demonstrated that IRSM frequency may depend on GC and CC genotypes of rs2010963 VEGF polymorphism and expression level of VEGF and Cx43 in IRSM patients was increased.

The effect of prednisolone on endometrial VGEF concentrations, Gene polymorphisms and pregnancy outcome in women with polycystic ovary syndrome: A retrospective cohort study

PCOS (Polycystic Ovary Syndrome) occurs due to hyperandrogenism, excessive androgen, abnormal growth, steroidogenesis and seems to be associated with abnormal Vascular endothelial growth factor (VEGF) level in serum. The treatment is provided on the basis of body symptoms to mute the excess production of hormone. The study assessed the effect of prednisolone treatment on the concentration of VEGF, pregnancy outcomes and variants of VEGF SNPs. In the current retrospective study, the samples were collected from PCOS female patients who received prednisolone and those who did not received it, were compared along with control, in terms of pregnancy results and the association complications. The results inferred that the prednisolone made the concentration of VEGF significantly to normal levels along with other pregnancy-related and growth-related hormones. But the reduced normal limits were achieved only among few patients whereas no significant improvement found in the women who received prednisolone and control, in terms of pregnancy outcomes or complications. Further, there were no relations between the impact of treatment and the variants of VEGF SNPs. To conclude, there is no solid evidence found in the current study with regards to notable beneficial effect when the patients were treated with prednisolone, either in pregnancy outcomes or VEGF SNPs. The current study results should be considered only as a preliminary one since the genetic polymorphisms tend to exhibit different results based on population, ethnic groups etc. The results yielded may not be generalized due to differences in genetic background.

Identifying Genetic Risk Factors for Diabetic Macular Edema and the Response to Treatment

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes mellitus (DM). DR is complex and the term encompasses several clinical subtypes of diabetic eye disease, including diabetic macular edema (DME), the most frequent cause of central vision loss in DR patients. Both genetic and environmental factors contribute to the pathophysiology of DR and its subtypes. While numerous studies have identified several susceptibility genes for DR, few have investigated the impact of genetics on DME susceptibility. This review will focus on the current literature surrounding genetic risk factors associated with DME. We will also highlight the small number of studies investigating the genetics of response to antivascular endothelial growth factor (anti-VEGF) injection, which is used to treat DME.

CACNB2 Is a Novel Susceptibility Gene for Diabetic Retinopathy in Type 1 Diabetes

Diabetic retinopathy is a common diabetes complication that threatens the eyesight and may eventually lead to acquired visual impairment or blindness. While a substantial heritability has been reported for proliferative diabetic retinopathy (PDR), only a few genetic risk factors have been identified. Using genome-wide sib pair linkage analysis including 361 individuals with type 1 diabetes, we found suggestive evidence of linkage with PDR at chromosome 10p12 overlapping the CACNB2 gene (logarithm of odds = 2.73). Evidence of association between variants in CACNB2 and PDR was also found in association analysis of 4,005 individuals with type 1 diabetes with an odds ratio of 0.83 and P value of 8.6 × 10^-4 for rs11014284. Sequencing of CACNB2 revealed two coding variants, R476C/rs202152674 and S502L/rs137886839. CACNB2 is abundantly expressed in retinal cells and encodes the β2 subunit of the L-type calcium channel. Blocking vascular endothelial growth factor (VEGF) by intravitreous anti-VEGF injections is a promising clinical therapy to treat PDR. Our data show that L-type calcium channels regulate VEGF expression and secretion from retinal pigment epithelial cells (ARPE19) and support the role of CACNB2 via regulation of VEGF in the pathogenesis of PDR. However, further genetic and functional studies are necessary to consolidate the findings.

Inhibition of Receptor for Advanced Glycation End Products as New Promising Strategy Treatment in Diabetic Retinopathy

BACKGROUND

Extensive intracellular and extracellular formation of advanced glycation end-products (AGEs) is considered a causative factor for vascular injury triggered by hyperglycemia in diabetes. The hyperglycemia will cause accumulation of AGEs, damage to pericytes, nerve growth factor (NGF), glial acid fibrillary protein (GFAP) and increase in vascular endothelial growth factor (VEGF).

AIM

This study aimed to assess the efficacy of RAGE inhibition in suppressing the development and progression of diabetic retinopathy through modulation of the inflammatory pathway involving NGF, GFAP, and VEGF.

METHODS

The design was in vivo experimental study. Thirty white rats were induced with Alloxan monohydrate. Rats were divided into 5 groups, normal, negative control, groups with an anti-RAGE dose of 1 μg/uL, the dose of 10 μg/uL and 100 μg/uL. After 4 weeks of treatment, HbA1c, NGF, and GFAP levels were measured using ELISA. Quantification of VEGF expression was done using the ImageJ® application. Data was expressed with mean ± SD. Independent T-test with ANOVA and Tukey's post hoc was done.

RESULTS

RAGE inhibitors yielded a significant decrease in blood glucose and HbA1c levels. VEGF and RAGE expression were reduced in anti-RAGE groups in various doses. Inhibition of RAGE reduced the damage of retinal pericytes, by reducing GFAP and increasing NGF, and reduced the formation of new blood vessels, by decreasing VEGF expression, in diabetic retinopathy.

CONCLUSION

Inhibition of receptor for advanced glycation end-products (RAGE) was effective in suppressing the development and progression of diabetic retinopathy.

Imaging and Biomarkers in Diabetic Macular Edema and Diabetic Retinopathy

PURPOSE OF REVIEW

Diabetic retinopathy (DR) is the leading cause of acquired vision loss in adults across the globe. Early identification and treatment of patients with DR is paramount for vision preservation. The aim of this review paper is to outline current and new imaging techniques and biomarkers that are valuable for clinical diagnosis and management of DR.

RECENT FINDINGS

Ultrawide field imaging and automated deep learning algorithms are recent advancements on traditional fundus photography and fluorescein angiography. Optical coherence tomography (OCT) and OCT angiography are techniques that image retinal anatomy and vasculature and OCT is routinely used to monitor response to treatment. Many circulating, vitreous, and genetic biomarkers have been studied to facilitate disease detection and development of new treatments. Recent advancements in retinal imaging and identification of promising new biomarkers for DR have the potential to increase detection, risk stratification, and treatment for patients with DR.