Impact of the genetic variants of <italic>GLCCI1</italic> on clinical features of asthmatic patients.

Abstract: Background: Several gene variants are associated with a response to an inhaled corticosteroids (ICSs) treatment in patients with bronchial asthma. A variant of the <italic>glucocorticoid‐induced transcript 1</italic> (<italic>GLCCI1</italic>) genes has previously been associated with decreased lung function improvement upon treatment with ICSs in patients with bronchial asthma. Another report has also demonstrated that this genetic biomarker did not influence the change in flow volume in 1 second. However, no studies have considered the treatment content and the <italic>GLCCI1</italic> variants. We were able to determine the relationship between the pulmonary function and clinical features and the variant of the <italic>GLCCI1</italic> in Japanese asthmatic patients receiving long‐term ICS treatment. Materials and methods: In this study, 405 patients with bronchial asthma, who were receiving ICS and living in Japan, were recruited, genotyped and underwent pulmonary function tests. To identify the GLCCI1 protein expression cells, endobronchial biopsy specimens were examined. Results: We found that the pulmonary function was not significantly different in the homozygotes compared to the wild types. Also, the homozygotes increased the risk of a sustained step‐up of the asthma treatment when compared to the wild type and heterozygotes. GLCCI1‐positive cells were localized to the bronchial epithelial cells. The amount of GLCCI1 protein that cultured epithelial cells harboring <italic>GLCCI1</italic> variants produced was less than the <italic>GLCCI1</italic> wild type in the presence of a corticosteroid. Conclusions: A worsening of pulmonary function caused by <italic>GLCCI1</italic> variants could be prevented due to recently used medications based on new action mechanisms. [ABSTRACT FROM AUTHOR]