BACKGROUND: Azathioprine (AZA) pharmacogenetics are complex and much studied. Genetic polymorphism in TPMT is known to influence treatment outcome. Xanthine oxidase/dehydrogenase (XDH) and aldehyde oxidase (AO) compete with TPMT to inactivate AZA. AIM: To assess whether genetic polymorphism in AOX1, XDH and MOCOS (the product of which activates the essential cofactor for AO and XDH) is associated with AZA treatment outcome in IBD. METHODS: Real-time PCR was conducted for a panel of single nucleotide polymorphism (SNPs) in AOX1, XDH and MOCOS using TaqMan SNP genotyping assays in a prospective cohort of 192 patients receiving AZA for IBD. RESULTS: Single nucleotide polymorphism AOX1 c.3404A > G (Asn1135Ser, rs55754655) predicted lack of AZA response (P = 0.035, OR 2.54, 95%CI 1.06-6.13) and when combined with TPMT activity, this information allowed stratification of a patient's chance of AZA response, ranging from 86% in patients where both markers were favourable to 33% where they were unfavourable (P < 0.0001). We also demonstrated a weak protective effect against adverse drug reactions (ADRs) from SNPs XDH c.837C > T (P = 0.048, OR 0.23, 95% CI 0.05-1.05) and MOCOS c.2107A > C, (P = 0.058 in recessive model, OR 0.64, 95%CI 0.36-1.15), which was stronger where they coincided (P = 0.019). CONCLUSION: These findings have important implications for clinical practice and our understanding of AZA metabolism.
BACKGROUND:Azathioprine (AZA) pharmacogenetics are complex and much studied. Genetic polymorphism in TPMT is known to influence treatment outcome. Xanthine oxidase/dehydrogenase (XDH) and aldehyde oxidase (AO) compete with TPMT to inactivate AZA. AIM: To assess whether genetic polymorphism in AOX1, XDH and MOCOS (the product of which activates the essential cofactor for AO and XDH) is associated with AZA treatment outcome in IBD. METHODS: Real-time PCR was conducted for a panel of single nucleotide polymorphism (SNPs) in AOX1, XDH and MOCOS using TaqMan SNP genotyping assays in a prospective cohort of 192 patients receiving AZA for IBD. RESULTS: Single nucleotide polymorphism AOX1 c.3404A > G (Asn1135Ser, rs55754655) predicted lack of AZA response (P = 0.035, OR 2.54, 95%CI 1.06-6.13) and when combined with TPMT activity, this information allowed stratification of a patient's chance of AZA response, ranging from 86% in patients where both markers were favourable to 33% where they were unfavourable (P < 0.0001). We also demonstrated a weak protective effect against adverse drug reactions (ADRs) from SNPs XDH c.837C > T (P = 0.048, OR 0.23, 95% CI 0.05-1.05) and MOCOS c.2107A > C, (P = 0.058 in recessive model, OR 0.64, 95%CI 0.36-1.15), which was stronger where they coincided (P = 0.019). CONCLUSION: These findings have important implications for clinical practice and our understanding of AZA metabolism.
Authors: Katerina Wroblova; Michal Kolorz; Marian Batovsky; Vladimir Zboril; Jana Suchankova; Milan Bartos; Boris Ulicny; Igor Pav; Ladislava Bartosova Journal: Dig Dis Sci Date: 2012-04-26 Impact factor: 3.199
Authors: E G Quetglas; A Armuzzi; S Wigge; G Fiorino; L Barnscheid; M Froelich; Silvio Danese Journal: Eur J Clin Pharmacol Date: 2015-05-27 Impact factor: 2.953
Authors: Lisa K Stamp; Tony R Merriman; Murray L Barclay; Jasvinder A Singh; Rebecca L Roberts; Daniel F B Wright; Nicola Dalbeth Journal: Semin Arthritis Rheum Date: 2014-05-09 Impact factor: 5.532
Authors: Daniel F B Wright; Lisa K Stamp; Tony R Merriman; Murray L Barclay; Stephen B Duffull; Nicholas H G Holford Journal: Eur J Clin Pharmacol Date: 2013-03-10 Impact factor: 2.953
Authors: E W Chua; S Cree; M L Barclay; K Doudney; K Lehnert; A Aitchison; M A Kennedy Journal: Pharmacogenomics J Date: 2015-03-10 Impact factor: 3.550