Influence of promoter polymorphisms of the TNF-α (-308G/A) and IL-6 (-174G/C) genes on therapeutic response to etanercept in rheumatoid arthritis

Uvod: Genetički faktori su značajni za predviđanje ishoda lečenja bolesnika sa reumatoidnim artritisom (RA). Cilj studije bio je da se ispita uticaj-308G/A TNF-α (rs 1800629) i -174G/C IL-6 (rs1800795) promotorskih polimorfizama na terapijski odgovor na etanercept. Metode: U studiju su bila uključena 73 pacijenta sa aktivnim RA. Terapijski odgovor je procenjivan posle 6 i 12 meseci terapije po kriterijumima Evropske lige protiv reumatizma. Genotipizacija pacijenata za polimorfizme -308G/A TNF-α i -174G/C IL-6 urađena je PCR-RFLP metodom i procenjivan je uticaj genotipova na odgovor na etanercept. Rezultati: Nije bilo razlike u procentu respondera (pacijenti kod kojih se DAS28 popravio gt 1,2) između pacijenata sa TNF-α -308GG, GA i AA genotipom ni posle 6 ni posle 12 meseci tretmana. Posle 12 meseci lečenja procenat respondera je bio značajno veći kod pacijenata sa IL-6 -174GG u odnosu na pacijente sa GC ili CC genotipom (p= 0,006, x2 test). Poređenje pacijenata prema kombinovanim IL-6/TNF-α genotipovima pokazalo je da je IL-6 -174GG / TNF-α -308GG genotip učestaliji kod respondera u odnosu na druge kombinovane genotipove (p= 0.022, x2 test). Tačnije, svi pacijenti sa kombinovanim IL-6 -174GG / TNF-α -308GG genotipom bili su responderi posle 12 meseci terapije etanerceptom. Zaključak: Studija pokazuje da bolesnici sa genotipovima koji se povezuju sa manjom produkcijom TNF-α i IL-6 najbolje odgovaraju na terapiju etanerceptom.Background: The study was undertaken to assess the influence of functional -308G /A TNF-α (rs 1800629) and -174G/C IL-6 (rs1800795) promoter polymorphisms on the therapeutic response to etanercept, a TNF-α blocker, in patients with rheumatoid arthritis (RA). Methods: Seventy-three patients suffering from active RA were studied, at baseline and 6 and 12 months after therapy. The therapeutic response was estimated according to the European League Against Rheumatism response criteria. Patients were genotyped for -308G /A TNF-α and -174G/C IL-6 polymorphisms by the PCR-RFLP method, and the influence of genotype on etanercept response was assessed. Results: No difference in the percentage of responders (patients who had DAS28 improvement gt 1.2) between patients with the TNF-α -308GG and GA and AA genotype was detected after 6 and 12 months of treatment. After 12 months of treatment the percentage of responders was significantly increased in patients with the IL-6 -174GG genotype compared with those with the GC or CC genotype (p=0.006 by Chi-square test). Evaluation of the patients according to their combined IL-6/TNF-α genotypes showed that patients with the IL-6 -174GG / TNF-α -308GG genotype were more frequent among the responders compared to those with other combined genotypes (p=0.022 by Chisquare test). More precisely, all patients with the combined IL-6 -174GG / TNF-α -308GG genotype were responders after 12 months of etanercept treatment. Conclusions: The study suggests that patients who are genetically low TNF-α and IL-6 producers are the best responders to etanercept therapy

Influence of Promoter Polymorphisms of the Tnf-α (-308g/A) and IL-6 (-174g/C) Genes on Therapeutic Response to Etanercept in Rheumatoid Arthritis

Background: The study was undertaken to assess the influence of functional -308G/A TNF-alpha (rs 1800629) and -174G/C IL-6 (rs1800795) promoter polymorphisms on the therapeutic response to etanercept, a TNF-alpha. blocker, in patients with rheumatoid arthritis (RA). Methods: Seventy-three patients suffering from active RA were studied, at baseline and 6 and 12 months after therapy. The therapeutic response was estimated according to the European League Against Rheumatism response criteria. Patients were genotyped for -308G/A TNF-alpha and -174G/C IL-6 polymorphisms by the PCR-RFLP method, and the influence of genotype on etanercept response was assessed. Results: No difference in the percentage of responders (patients who had DAS28 improvement > 1.2) between patients with the TNF-alpha -308GG and GA and AA genotype was detected after 6 and 12 months of treatment. After 12 months of treatment the percentage of responders was significantly increased in patients with the IL-6 -174GG genotype compared with those with the GC or CC genotype (p=0.006 by Chi-square test). Evaluation of the patients according to their combined IL-6/INF-alpha genotypes showed that patients with the IL-6 -174GG / TNF-alpha -308GG genotype were more frequent among the responders compared to those with other combined genotypes (p=0.022 by Chi-square test). More precisely, all patients with the combined IL-6 -174GG / TNF-alpha -308GG genotype were responders after 12 months of etanercept treatment. Conclusions: The study suggests that patients who are genetically low TNF-alpha and IL-6 producers are the best responders to etanercept therapy

-174G/C interleukin-6 gene promoter polymorphism predicts therapeutic response to etanercept in rheumatoid arthritis

To examine whether -174G/C interleukin-6 (IL-6) gene polymorphism, previously reported to correlate with IL-6 level, influences response to etanercept therapy in patients with rheumatoid arthritis. Seventy-seven patients with active RA were studied, at baseline and 6- and 12-month follow-up after etanercept therapy. Treatment response was estimated according to the European League Against Rheumatism response criteria. RA patients were genotyped for -174G/C IL-6 gene polymorphism by the PCR-RFLP method, and influence of genotype at this polymorphism to clinical response to etanercept was assessed. After 12 months of treatment, the percentage of responders (patients who had DAS28 improvement > 1.2) was significantly increased in patients carrying the IL-6 -174G/G genotype (95.7 %) compared with those with the G/C (75.6 %) or CC (44.4 %) genotype (p = 0.006 by Chi-square test). No significant difference in the mean values of DAS28 improvement was observed between groups with different genotype. RA patients with an IL-6 -174GG genotype respond to etanercept better than patients with GC or CC genotype. This finding, if confirmed in future studies, suggests that the -174G/C IL-6 polymorphism may be a genetic marker of responsiveness to tumor necrosis factor-alpha (TNF-alpha) blockers in RA

-174G/C interleukin-6 gene promoter polymorphism predicts therapeutic response to etanercept in rheumatoid arthritis

To examine whether -174G/C interleukin-6 (IL-6) gene polymorphism, previously reported to correlate with IL-6 level, influences response to etanercept therapy in patients with rheumatoid arthritis. Seventy-seven patients with active RA were studied, at baseline and 6- and 12-month follow-up after etanercept therapy. Treatment response was estimated according to the European League Against Rheumatism response criteria. RA patients were genotyped for -174G/C IL-6 gene polymorphism by the PCR-RFLP method, and influence of genotype at this polymorphism to clinical response to etanercept was assessed. After 12 months of treatment, the percentage of responders (patients who had DAS28 improvement gt 1.2) was significantly increased in patients carrying the IL-6 -174G/G genotype (95.7 %) compared with those with the G/C (75.6 %) or CC (44.4 %) genotype (p = 0.006 by Chi-square test). No significant difference in the mean values of DAS28 improvement was observed between groups with different genotype. RA patients with an IL-6 -174GG genotype respond to etanercept better than patients with GC or CC genotype. This finding, if confirmed in future studies, suggests that the -174G/C IL-6 polymorphism may be a genetic marker of responsiveness to tumor necrosis factor-alpha (TNF-alpha) blockers in RA