Role of glucocorticoid receptor beta in the development of steroid resistance

Glucocorticoids (GCs) are the most commonly used anti-inflammatory drugs for the treatment of inflammatory diseases, despite the fact that the resistance to them is increasing due to various circumstances. GC insensitivity is an important clinical issue that is associated with life-threatening disease progression. Currently, there is no reliable biomarker that can be used to define steroid resistance. According to several studies, increased expression of the glucocorticoid receptor beta (GR-β) isoform is associated with steroid resistance. The purpose of this review is to analyse the correlation between GR-β expression and the occurrence of steroid therapy-resistant diseases and to determine its potential as a biomarker. This review summarizes studies that point out increased GR-β expression in steroid-resistant groups of patients compared to steroid-sensitive groups. Articles included in the review focus on asthma, nasal polyposis, ulcerative colitis, and other chronic inflammatory diseases in which resistance to steroid therapy is observed. GR-β levels have also been shown to be elevated in patients with allergic rhinitis, Crohn's disease and rheumatoid arthritis. In most studies, higher levels of GR-β were detected in peripheral blood mononuclear cells (PBMC) by reverse transcription polymerase chain reaction (RT-PCR). Increased expression of GR-β is mostly associated with steroid resistance. Thus, it can potentially be used as a biomarker of steroid resistance-related disorders.