Association between Polymorphisms in CFH, ARMS2, CFI, and C3 Genes and Response to Anti-VEGF Treatment in Neovascular Age-Related Macular Degeneration

Complement proteins and complement regulatory proteins are associated with age-related macular degeneration stage and treatment response

BACKGROUND

Dysregulation of the complement system is involved in development of age-related macular degeneration (AMD). The complement cascade is regulated by membrane bound complement regulatory proteins (Cregs) on mononuclear leukocytes among others. This study aims to investigate systemic complement proteins and Cregs in AMD stages and their association with treatment response in neovascular AMD (nAMD).

METHODS

In this clinical prospective study, treatment-naïve patients with nAMD, intermediate AMD (iAMD) and healthy controls were recruited and systemic complement proteins C3, C3a and C5a were investigated with electrochemiluminescence immunoassays, and Creg expression (CD35, CD46 and CD59) on T cells (CD4 + and CD8+) and monocytes (classical, intermediate and non-classical) investigated with flow cytometry. Treatment response in nAMD patients was evaluated after loading dose and after one year, and categorized as good, partial or poor. Complement proteins and Creg expression levels were compared between healthy controls, iAMD and nAMD, as well as between good, partial and poor nAMD treatment response groups. Polymorphisms in the CFH and ARMS2 genes were analyzed and compared to complement proteins and Creg expression levels in nAMD patients.

RESULTS

One hundred patients with nAMD, 34 patients with iAMD and 61 healthy controls were included. 94 nAMD patients completed the 1-year follow-up. Distribution of treatment response in nAMD was 61 (65%) good, 26 (28%) partial, and 7 (7%) poor responders. The distribution of 1-year treatment response was 50 (53%) good, 33 (36%) partial, and 11 (11%) poor responders. The concentrations of systemic C3, C3a, and the C3a/C3-ratio were significantly increased in patients with nAMD compared to healthy controls (P < 0.001, P = 0.002, and P = 0.035, respectively). Systemic C3 was also increased in iAMD compared to healthy controls (P = 0.031). The proportion of CD46 + CD4 + T cells and CD59 + intermediate monocytes were significantly decreased in patients with nAMD compared to healthy controls (P = 0.018 and P = 0.042, respectively). The post-loading dose partial treatment response group had significantly lower concentrations of C3a and C5a compared to the good response group (P = 0.005 and P = 0.042, respectively). The proportion of CD35 + monocytes was significantly lower in the 1-year partial response group compared to the 1-year good response group (P = 0.039). High-risk CFH genotypes in nAMD patients was associated with increased C3a, C3a/C3-ratio, and expression levels of CD35 + CD8 + T cells and CD46 + classical monocytes, while expression level of CD46 + non-classical monocytes was decreased.

CONCLUSION

Elevated concentrations of systemic complement proteins were found in patients with iAMD and nAMD. Decreased Creg expression levels were found in patients with nAMD. Partially responding nAMD patients had a dysregulated complement system and Cregs compared to good responders.

The interactions between ARMS2, CFH, VEGF-A and environmental factors on the risk of age-related macular degeneration

Background

Age related macular degeneration (AMD) is a multifactorial disease caused by a combination of environmental and genetic factors. The prevalence of allele and genotypeof AMD-related genes is varied throughout the world due to racial and ethnic differences. Number of previous studies have shown that the polymorphisms in the ARMS2, CFH and VEGF-A genes are associated with AMD. In Mongolia, there is a lack of sufficient data on AMD development in its population and thus needs more studies on the topic. Therefore, it needs more studies about AMD development in the population. For this reason, we have investigated several specified polymorphisms in CFH, VEGF-A and ARMS2 genes to reveal a relationship with AMD and determine the prevalence of alleles and genotypes of the genes in Mongolian population.

Methods

Totally 161 AMD patients and 223 controls were enrolled in this case-control study. The polymorphisms in CFH, ARMS2 and VEGF-A were detected by using the methods of allele-specific polymerase chain reaction (ASPCR) and PCR based restriction fragment length polymorphism (RFLP). Statistical analysis were performed by STATA 13.0, SNPAlyze 9.0 and MDR 3.0.2.

Results

According to the study result, the characteristics of hypertension, constant-wearing sunglasses and anticoagulant medications in AMD group were significantly different from those in the control group. As for the dominant model, T allele of ARMS2 rs10490924 (cOR=4.45; 95% CI, 2.44-8.13, p<0.001, aOR=5.08; 95% CI, 2.70-9.59, p<0.001) was more frequent among patients with AMD in comparison with the control group. Also, G/G genotype of CFH rs800292 (cOR=11.61; 95% CI, 3.41-39.51, p<0.001, aOR=12.49; 95% CI, 3.47-44.91, p<0.001) and G/G genotype of CFH rs1065489 (cOR=4.19; 95% CI, 2.53-6.93, p<0.001, aOR=4.67; 95% CI, 2.71-8.05, p<0.001) were significantly higher in AMD group after Bonferroni correction. This result suggests that people who carrying the risk genotypes of these polymorphisms had an increased risk for AMD development. As for the models of three or more SNP interactions, the participants with any combinations of risk genotypes have 6 to 106-fold higher risk for AMD development. This result suggests that there is some positive-additive interaction existing between the genetic variants of ARMS2, CFH and VEGF-A genes for AMD development. Our study also revealed that the participants with hypertension and carrying G/G for rs1065489 in CFH gene or non G/G for rs10490924 in ARMS2 gene genotypes had 9 to 14 times higher risk for AMD development (cOR=9.05; 95% CI, 4.38-18.68, p<0.001, RERI=4.546; AP=0.502, S=2.298, cOR=13.98; 95% CI, 3.19-61.1, p<0.001, RERI=5.85; AP=0.419, S=1.821) with high level of significance. Moreover, it was found that the participants who avoided wearing sunglasses and had the G/G genotype of ARMS2 rs10490924 or G/G genotype of CFH rs800292 had an extremely higher risk for AMD development (p<.001).

Conclusions

In conclusion, it was observed that the combination of SNPs in ARMS2, CFH and VEGF-A genes increase the risk for AMD with 6 to 106-fold. Moreover, we found that the participants with hypertension and carrying the non G/G genotype of ARMS2 rs10490924 or the G/G genotype of CFH rs800292 had an extremely higher risk of AMD development.

ANO2 Genetic Variants and Anti-VEGF Treatment Response in Neovascular AMD: A Pharmacogenetic Substudy of VIEW 1 and VIEW 2

Purpose

This analysis investigated potential associations between gene variants and clinical end points in the VIEW 1 and 2 randomized clinical trials of intravitreal aflibercept and ranibizumab in neovascular age-related macular degeneration (AMD).

Methods

A genome-wide association analysis was conducted in a subgroup of patients from VIEW 1 and 2 consenting to the optional pharmacogenetic analysis.

Results

Data were pooled from 780 samples from patients representative of the overall VIEW 1 and 2 populations. After Bonferroni correction for multiplicity and statistical adjustment for baseline risk factors, no significant associations were found between previously identified prognostic AMD gene variants and treatment response according to key prespecified VIEW 1 and 2 end points. Genome-wide, there were no significant genetic associations in patients experiencing gains of ≥15 Early Treatment of Diabetic Retinopathy Study letters after 1 or 2 years of treatment. A cluster of variants in ANO2 (encoding anoctamin 2, a calcium-activated chloride channel expressed on photoreceptor cells) on chromosome 12 reached the level of significance for loss of ≥5 letters after 1 year of treatment (P < 5 × 10-8), with the ANO2 rs2110166 SNP demonstrating highly significant association (P = 1.99 × 10-8). Carriers of the ANO2 rs2110166 TT genotype showed a robust increase in visual acuity versus baseline compared with a small decrease in those with the TC genotype.

Conclusions

None of the potential prognostic candidate genes were associated with the clinical end points for treated patients. Preliminary analyses suggest an association of ANO2 with retinal function, with a potential impact on vision of approximately one line over at least the first year. Further investigation of the function of ANO2 in retinal pathophysiology is merited.

Pharmacogenetic Association between Allelic Variants of the Autophagy-Related Genes and Anti-Vascular Endothelial Growth Factor Treatment Response in Neovascular Age-Related Macular Degeneration

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of late-onset blindness in elderly. The occurrence and development of AMD is a multifactorial complex process where autophagy plays an important role. The first-line drugs for neovascular AMD (nAMD) are inhibitors of VEGF, with up to 30% of patients having an incomplete response to treatment. Genetic factors may influence the response to anti-VEGF therapy and explain treatment outcome variability. We aimed to estimate the role of polymorphic markers of the MTOR (rs1064261, rs1057079, rs11121704, rs2295080), SQSTM1 (rs10277), ULK1 (rs11246867, rs3088051), MAP1LC3A (rs73105013) and ATG5 (rs573775) genes in the development of nAMD and the efficacy of anti-VEGF therapy response.

METHODS

Genotyping by allele-specific PCR was performed in 317 controls and 315 nAMD patients in the Russian population. Of them, 196 treatment-naive nAMD patients underwent three monthly intravitreal injections (IVIs) of aflibercept. Genotypic frequencies were compared with OCT markers of therapy effectiveness and best-corrected visual acuity (BCVA) measures. The main outcomes were the BCVA gain and decrease in central retinal thickness (CRT).

RESULTS

MTOR-rs1057079-C, MTOR-rs11121704-C and MTOR-rs2295080-G alleles were associated with an increased risk of nAMD. The BCVA was increased in 117 (59.7%) patients by 10 [5-20] letters, did not changed in 59 (30.1%), and was decreased in 20 (10.2%) patients. ULK1-rs3088051 was associated with BCVA change. Among patients with the TT and CT genotypes for ULK1-rs3088051, an improvement in visual acuity was noted in 67.6% and 53.8% of cases, while in patients with the CC genotype, an increase in BCVA was recorded in 37.5% of cases (p = 0.01). The decrease in CRT was associated with SQSTM1-rs10277 (p = 0.001): it was significantly higher in TT (93 [58-122] mkm) and CT (66 [30-105] mkm) carriers compared to the CC genotype (47 [24-68] mkm). Other SNPs did not show significant associations with the outcome of anti-VEGF treatment.

CONCLUSIONS

MTOR gene polymorphisms are moderately associated with the risk of nAMD. SQSTM1-rs10277 and ULK1-rs3088051 may influence short-term response to intravitreal anti-VEGF treatment. The results suggest that autophagy could be a target for future drugs to overcome resistance to anti-VEGF therapy.

Overview on the Link Between the Complement System and Auto-Immune Articular and Pulmonary Disease

Complement system (CS) dysregulation is a key factor in the pathogenesis of different autoimmune diseases playing a central role in many immune innate and adaptive processes. Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by ta breach of self-tolerance leading to a synovitis and extra-articular manifestations. The CS is activated in RA and seems not only to mediate direct tissue damage but also play a role in the initiation of RA pathogenetic mechanisms through interactions with citrullinated proteins. Interstitial lung disease (ILD) represents the most common extra-articular manifestation that can lead to progressive fibrosis. In this review, we focused on the evidence of CS dysregulation in RA and in ILD, and highlighted the role of the CS in both the innate and adaptive immune responses in the development of diseases, by using idiopathic pulmonary fibrosis as a model of lung disease. As a proof of concept, we dissected the evidence that several treatments used to treat RA and ILD such as glucocorticoids, pirfenidone, disease modifying antirheumatic drugs, targeted biologics such as tumor necrosis factor (TNF)-inhibitors, rituximab, tocilizumab, and nintedanib may act indirectly on the CS, suggesting that the CS might represent a potential therapeutic target in these complex diseases.

Emerging therapeutic strategies for unmet need in neovascular age-related macular degeneration

Neovascular age-related macular degeneration (nAMD) is a major cause of visual impairment and blindness. Anti-vascular endothelial growth factor (VEGF) agents, such as ranibizumab, bevacizumab, aflibercept, brolucizumab and faricimab have revolutionized the clinical management of nAMD. However, there remains an unmet clinical need for new and improved therapies for nAMD, since many patients do not respond optimally, may lose response over time or exhibit sub-optimal durability, impacting on real world effectiveness. Evidence is emerging that targeting VEGF-A alone, as most agents have done until recently, may be insufficient and agents that target multiple pathways (e.g., aflibercept, faricimab and others in development) may be more efficacious. This article reviews issues and limitations that have arisen from the use of existing anti-VEGF agents, and argues that the future may lie in multi-targeted therapies including alternative agents and modalities that target both the VEGF ligand/receptor system as well as other pathways.

Genetic Aspects of Age-Related Macular Degeneration and Their Therapeutic Potential

Age-related macular degeneration (AMD) is a complex and multifactorial disease, resulting from the interaction of environmental and genetic factors. The continuous discovery of associations between genetic polymorphisms and AMD gives reason for the pivotal role attributed to the genetic component to its development. In that light, genetic tests and polygenic scores have been created to predict the risk of development and response to therapy. Still, none of them have yet been validated. Furthermore, there is no evidence from a clinical trial that the determination of the individual genetic structure can improve treatment outcomes. In this comprehensive review, we summarize the polymorphisms of the main pathogenetic ways involved in AMD development to identify which of them constitutes a potential therapeutic target. As complement overactivation plays a major role, the modulation of targeted complement proteins seems to be a promising therapeutic approach. Herein, we summarize the complement-modulating molecules now undergoing clinical trials, enlightening those in an advanced phase of trial. Gene therapy is a potential innovative one-time treatment, and its relevance is quickly evolving in the field of retinal diseases. We describe the state of the art of gene therapies now undergoing clinical trials both in the field of complement-suppressors and that of anti-VEGF.