Objective: To evaluate expression of cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LO) associated with interleukin (IL)-4 promoter polymorphism -590 in nasal polyp tissues.
Study design and setting: A prospective controlled study. A venous blood sample was taken to determine the genotype in 61 nasal polyp subjects. The C-590T variant was determined by the polymerase chain reaction-restriction fragment length polymorphism method. The expression of 5-LO and COX-2 was determined with immunohistochemical staining in 37 nasal polyp tissues associated with genotype.
Results: The genotype frequencies at position -590 of the IL-4 gene in the patients with nasal polyp were C/C (8.20%), C/T (40.98%), and T/T (50.82%). There was no significantly increased expression of COX-2 among genotypes. The 5-LO expression was significantly increased in C/C compared with C/T and T/T.
Conclusion: We suggested that the IL-4 promoter polymorphism -590 C/C is associated with the expression of 5-LO in the patients with nasal polyp.