Genetic predictors of response to photodynamictherapy

Epigenetic role of LINE-1 methylation and key genes in pregnancy maintenance

Spontaneous abortion is a pregnancy complication characterized by complex and multifactorial etiology. About 5% of childbearing women are globally affected by early pregnancy loss (EPL) and most of them experience recurrence (RPL). Epigenetic mechanisms and controlled inflammation are crucial for pregnancy maintenance and genetic predispositions may increase the risk affecting the maternal-fetal crosstalk. Combined analyses of global methylation, inflammation and inherited predispositions may contribute to define pregnancy loss etiopathogenesis. LINE-1 epigenetic regulation plays crucial roles during embryo implantation, and its hypomethylation has been associated with senescence and several complex diseases. By analysing a group of 230 women who have gone through pregnancy interruption and comparing those experiencing spontaneous EPL (n = 123; RPL, 54.5%) with a group of normal pregnant who underwent to voluntary interruption (VPI, n = 107), the single statistical analysis revealed significant lower (P < 0.00001) LINE-1 methylation and higher (P < 0.0001) mean cytokine levels (CKs: IL6, IL10, IL17A, IL23) in EPL. Genotyping of the following SNPs accounted for different EPL/RPL risk odds ratio: F13A1 rs5985 (OR = 0.24; 0.06-0.90); F13B rs6003 (OR = 0.23; 0.047-1.1); FGA rs6050 (OR = 0.58; 0.33-1.0); CRP rs2808635/rs876538 (OR = 0.15; 0.014-0.81); ABO rs657152 (OR = 0.48; 0.22-1.08); TP53 rs1042522 (OR = 0.54; 0.32-0.92); MTHFR rs1801133/rs1801131 (OR = 2.03; 1.2-3.47) and FGB rs1800790 (OR = 1.97; 1.01-3.87), although Bonferroni correction did not reach significant outputs. Principal Component Analysis (PCA) and logistic regression disclosed further SNPs positive/negative associations (e.g. APOE rs7412/rs429358; FGB rs1800790; CFH rs1061170) differently arranged and sorted in four significant PCs: PC1 (F13A, methylation, CKs); PC3 (CRP, MTHFR, age, methylation); PC4 (F13B, FGA, FGB, APOE, TP53, age, methylation); PC6 (F13A, CFH, ABO, MTHFR, TP53, age), yielding further statistical power to the association models. In detail, positive EPL risk association was with PC1 (OR = 1.81; 1.33-2.45; P < 0.0001) and negative associations with PC3 (OR = 0.489; 0.37-0.66; P < 0.0001); PC4 (OR = 0.72; 0.55-0.94; P = 0.018) and PC6 (OR = 0.61; 0.46-0.81; P = 0.001). Moreover, significant inverse associations were detected between methylation and CKs levels in the whole group (rIL10 = - 0.22; rIL17A = - 0.25; rIL23 = - 0.19; rIL6 = - 0.22), and methylation with age in the whole group, EPL and RPL subgroups (r2TOT = 0.147; r2EPL = 0.136; r2 RPL = 0.248), while VPI controls lost significance (r2VPI = 0.011). This study provides a valuable multilayer approach for investigating epigenetic abnormalities in pregnancy loss suggesting genetic-driven dysregulations and anomalous epigenetic mechanisms potentially mediated by LINE-1 hypomethylation. Women with unexplained EPL might benefit of such investigations, providing new insights for predicting the pregnancy outcome and for treating at risk women with novel targeted epidrugs.

Host genetics impact on SARS-CoV-2 vaccine-induced immunoglobulin levels and dynamics: The role of TP53, ABO, APOE, ACE2, HLA-A, and CRP genes

Background: Development and worldwide availability of safe and effective vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) to fight severe symptoms of coronavirus disease 2019 (COVID-19) and block the pandemic have been a great achievement and stimulated researchers on understanding the efficacy and duration of different vaccine types. Methods: We investigated the levels of anti-SARS-CoV-2 antibodies (IgG) and neutralizing antibodies (NAbs) in 195 healthy adult subjects belonging to the staff of the University-Hospital of Ferrara (Italy) starting from 15 days up to 190 days (about 6 months) after the second dose of the BNT162b2 (Pfizer-BioNTech) mRNA-based vaccine (n = 128) or ChAdOx1 (AstraZeneca) adenovirus-based vaccine (n = 67) using a combined approach of serological and genomics investigations. Results: A strong correlation between IgG and NAb levels was detected during the 190 days of follow-up (r 2 = 0.807; p < 0.0001) and was confirmed during the first 90 days (T1) after vaccination (r 2 = 0.789; p = 0.0001) and 91-190 days (T2) after vaccination (r 2 = 0.764; p = 0.0001) for both vaccine types (r 2 = 0.842; p = 0.0001 and r 2 = 0.780; p = 0.0001 for mRNA- and adenovirus-based vaccine, respectively). In addition to age (p < 0.01), sex (p = 0.03), and type of vaccine (p < 0.0001), which partially accounted for the remarkable individual differences observed in the antibody levels and dynamics, interesting genetic determinants appeared as significant modifiers of both IgG and NAb responses among the selected genes investigated (TP53, rs1042522; APOE, rs7412/rs429358; ABO, rs657152; ACE2, rs2285666; HLA-A rs2571381/rs2499; CRP, rs2808635/rs876538; LZTFL1, rs35044562; OAS3, rs10735079; SLC6A20, rs11385942; CFH, rs1061170; and ACE1, ins/del, rs4646994). In detail, regression analysis and mean antibody level comparison yielded appreciable differences after genotype stratification (P1 and P2, respectively, for IgG and NAb distribution) in the whole cohort and/or in the mRNA-based vaccine in the following genes: TP53, rs1042522 (P1 = 0.03; P2 = 0.04); ABO, rs657152 (P1 = 0.01; P2 = 0.03); APOE, rs7412/rs429358 (P1 = 0.0018; P2 = 0.0002); ACE2, rs2285666 (P1 = 0.014; P2 = 0.009); HLA-A, rs2571381/rs2499 (P1 = 0.02; P2 = 0.03); and CRP, rs2808635/rs876538 (P1 = 0.01 and P2 = 0.09). Conclusion: High- or low-responsive subjects can be identified among healthy adult vaccinated subjects after targeted genetic screening. This suggests that favorable genetic backgrounds may support the progression of an effective vaccine-induced immune response, though no definite conclusions can be drawn on the real effectiveness ascribed to a specific vaccine or to the different extent of a genotype-driven humoral response. The interplay between data from the polygenic predictive markers and serological screening stratified by demogeographic information can help to recognize the individual humoral response, accounting for ethnic and geographical differences, in both COVID-19 and anti-SARS-CoV-2 vaccinations.

Revisiting the role of factor H in age-related macular degeneration: Insights from complement-mediated renal disease and rare genetic variants

Ophthalmologists are long familiar with the eye showing signs of systemic disease, but the association between age-related macular degeneration and abnormal complement activation, common to several renal disorders, has only recently been elucidated. Although complement activation products were identified in drusen almost three decades ago, it was not until the early 21st century that a single-nucleotide polymorphism in the complement factor H gene was identified as a major heritable determinant of age-related macular degeneration, galvanizing global efforts to unravel the pathogenesis of this common disease. Advances in proteomic analyses and familial aggregation studies have revealed distinctive clinical phenotypes segregated by the functional effects of common and rare genetic variants on the mature protein and its splice variant, factor H-like protein 1. The predominance of loss-of-function, N-terminal mutations implicate age-related macular degeneration as a disease of general complement dysregulation, offering several therapeutic avenues for its modulation. Here, we explore the molecular impact of these mutations/polymorphisms on the ability of variant factor H/factor H-like protein 1 to localize to polyanions, pentraxins, proinflammatory triggers, and cell surfaces across ocular and renal tissues and exert its multimodal regulatory functions and their clinical implications. Finally, we critically evaluate key therapeutic and diagnostic efforts in this rapidly evolving field.

Impact of methylenetetrahydrofolate reductase C677T polymorphism on the efficacy of photodynamic therapy in patients with neovascular age-related macular degeneration

The most severe visual impairments due to age-related macular degeneration (AMD) are frequently caused by the occurrence of choroidal neovascularization (CNV). Although photodynamic therapy with verteporfin (PDT-V) is currently a second-line treatment for neovascular AMD, it can be conveniently combined with drugs acting against vascular endothelial growth factor (anti-VEGF) to reduce the healthcare burden associated with the growing necessity of anti-VEGF intravitreal re-injection. Because the common 677 C > T polymorphism of the methylenetetrahydrofolate reductase gene (MTHFR-C677T; rs1801133) has been described as predictor of satisfactory short-term responsiveness of AMD-related CNV to PDT-V, we retrospectively examined the outcomes of 371 Caucasian patients treated with standardized, pro-re-nata, photodynamic regimen for 24 months. Responder (R) and non-responder (NR) patients were distinguished on the basis of the total number of scheduled PDT-V (TN-PDT-V) and change of best-corrected visual acuity (∆-BCVA). The risk for both TN-PDT-V and ∆-BCVA to pass from R to NR group was strongly correlated with CT and TT genotypes of MTHFR-C677T variant resulting, respectively, in odd ratios of 0.19 [95% CI, 0.12-0.32] and 0.09 [95% CI, 0.04-0.21] (P < 0.001), and odd ratios of 0.24 [95% CI, 0.15-0.39] and 0.03 [95% CI, 0.01-0.11] (P < 0.001). These pharmacogenetic findings indicate a rational basis to optimize the future clinical application of PDT-V during the combined treatments of AMD-related CNV, highlighting the role of thrombophilia to be aware of the efficacy profile of photodynamic therapy.

Inherited genetic predispositions in F13A1 and F13B genes predict abdominal adhesion formation: identification of gender prognostic indicators

Abdominal adhesions (AA) account for the most common complication of peritoneal surgery with bowel obstruction being the severest problem in the absence of effective predicting biomarkers. Anti-AA-barriers or adhesiolysis did not completely prevent bowel obstruction, although there is evidence they might reduce related complications requiring reoperation. In addition, gender-related predispositions have not been adequately investigated. We explored the role of coagulation Factor XIII (F13A1 and F13B subunit-genes) in patients following laparotomy, mostly median/lower median incision line. Globally, 426 patients (54%,♀), were PCR-SNP-genotyped for FXIIIA V34L (rs5985), FXIIIA P564L (rs5982), FXIIIA Y204F (rs3024477) and FXIIIB H95R (rs6003). Patients' clinical phenotypes were: Group-A (n = 212), those who developed AA, and 55.2% of them developed bowel obstruction (subgroup-A1), the remaining were subgroup-A2; Group B (n = 214) were those who did not develop AA (subgroup-B1; 53.3%) or symptoms/complications (subgroup-B2). Among different laparotomy, colon surgery associated with AA at a major extent (OR = 5.1; 3.24-7.8; P < 0.0001) with different gender scores (♀OR = 5.33; 2.32-12.23; P < 0.0001 and ♂OR = 3.44; 1.58-7.49; P < 0.0001). Among SNPs, P564L (OR = 4.42; 1.45-13.4; P = 0.008) and Y204F (OR = 7.78; 1.62-37.3; P = 0.01) significantly predicted bowel obstruction and survival-analyses yielded interesting gender distinctions (♀HR = 5.28; 2.36-11.8; P = 0.00005; ♂HR = 2.22; 1.31-3.85; P = 0.0034). Active compounds preventing AA belong to the anticoagulant/fibrinolysis areas, suggesting them candidate investigation targets. We identified novel prognostic markers to predict AA/bowel obstruction giving insights to design novel therapeutic and gender prevention programs.

Effect of Factor XIII-A G185T Polymorphism on Visual Prognosis after Photodynamic Therapy for Neovascular Macular Degeneration

Macular degenerations represent leading causes of central blindness or low vision in developed countries. Most of these severe visual disabilities are due to age-related macular degeneration (AMD) and pathologic myopia (PM), both of which are frequently complicated by subfoveal choroidal neovascularization (CNV). Photodynamic therapy with verteporfin (PDT-V) is still employed for CNV treatment in selected cases or in combined regimen. In Caucasian patients, the common polymorphism G185T of factor XIII-A gene (FXIII-A-G185T; rs5985) has been described as predictor of poor angiographic CNV responsiveness to PDT-V. Nevertheless, the prognostic implications of this pharmacogenetic determinant on long-term visual outcome after a PDT-V regimen have not been evaluated. We retrospectively selected Caucasian patients presenting with treatment-naive CNV and receiving standardized PDT-V protocol for two years. The study population included patients affected by subfoveal CNV secondary to AMD or PM. We assessed the correlations between the polymorphic allele T of FXIII-A-G185T and: (1) total number of photodynamic treatments; and (2) change in visual acuity from baseline to the end of the follow-up period. Considering a total study population of 412 patients with neovascular AMD or PM, the carriers of 185 T-allele of FXIII-A (GT or TT genotype) received a higher number of photodynamic treatments than patients without it (GG wild-type genotype) (p < 0.01; mean number of PDT-V: 5.51 vs. 3.76, respectively). Moreover, patients with 185 T-allele of FXIII-A had a more marked worsening of visual acuity at 24 months than those with the GG-185 wild genotype (p < 0.01; mean difference in logMAR visual acuity: 0.22 vs. 0.08, respectively). The present findings show that the G185T polymorphism of the FXIII-A gene is associated with significant differences in the long-term therapeutic outcomes of patients treated with standardized PDT-V protocol. The comprehensive appraisal of both anti-thrombophilic effects due to FXIII-A G185T variant and photo-thrombotic action of PDT-V toward CNV provides several clues about the rationale of this intriguing pharmacogenetic correlation. Further investigations are warranted to outline the appropriate paradigm for guiding PDT-V utilization in the course of the combined therapeutic protocol for neovascular macular degeneration.

Genetic predictive biomarkers of anti-VEGF treatment response in patients with neovascular age-related macular degeneration

Anti-vascular endothelial growth factor (anti-VEGF) therapies for neovascular age-related macular degeneration (nAMD) have proven efficacy at a study-population level, although individual patient responses vary, with most of the patients responding well to anti-VEGF therapies, while a few respond poorly. The pathogenesis of AMD is known to have a genetic component, but it is unclear if any particular genotype can predict response to anti-VEGF therapy. With the advent of less expensive genotyping technology, there have been numerous studies within this area. Here we analyze potential biomarker candidates identified that could be used in a clinical setting to predict response to anti-VEGF treatment of nAMD. We analyze single nucleotide polymorphisms (SNPs) identified from 39 publications. The SNPs that appeared to be of most importance fell into two main groups: those previously associated with AMD pathogenesis and those within the signaling pathway targeted by anti-VEGF therapies. A number of small studies found evidence supporting an association between anti-VEGF treatment response and two SNPs, CFH rs1061170 and VEGFA rs699947, but results from randomized controlled trials found no such association. It is possible that, in the future, the cumulative effect of several high-risk SNPs may prove useful in a clinical setting and that other genetic biomarkers may emerge.

Mechanism of inflammation in age-related macular degeneration

Age-related macular degeneration (AMD) is a multifactorial disease that represents the most common cause of irreversible visual impairment among people over the age of 50 in Europe, the United States, and Australia, accounting for up to 50% of all cases of central blindness. Risk factors of AMD are heterogeneous, mainly including increasing age and different genetic predispositions, together with several environmental/epigenetic factors, that is, cigarette smoking, dietary habits, and phototoxic exposure. In the aging retina, free radicals and oxidized lipoproteins are considered to be major causes of tissue stress resulting in local triggers for parainflammation, a chronic status which contributes to initiation and/or progression of many human neurodegenerative diseases such as AMD. Experimental and clinical evidences strongly indicate the pathogenetic role of immunologic processes in AMD occurrence, consisting of production of inflammatory related molecules, recruitment of macrophages, complement activation, microglial activation and accumulation within those structures that compose an essential area of the retina known as macula lutea. This paper reviews some attractive aspects of the literature about the mechanisms of inflammation in AMD, especially focusing on those findings or arguments more directly translatable to improve the clinical management of patients with AMD and to prevent the severe vision loss caused by this disease.