11β-hydroxysteroid dehydrogenase type 1 as a predictive biomarker for glucocorticoid treatment response in...

Glucocorticoid therapy is commonly used in inflammatory myopathies (IMs); however, patients' responses are variable, and predictive biomarkers remain unavailable. 11  -hydroxysteroid dehydrogenase type 1 (11  -HSD1), a key enzyme regulating intracellular glucocorticoid activation, may influence treatment response. This study evaluated the relationship between muscle 11  -HSD1 expression and clinical response to glucocorticoid therapy.

This study included 32 patients with biopsy-confirmed IMs, of whom 25 received post-biopsy prednisolone (0.5-1 mg/kg/day) for approximately 8 months without glucocorticoid-sparing agents. Clinical response was evaluated based on muscle strength, symptom improvement, and creatinine kinase (CK) reduction. Muscle 11  -HSD1 expression was assessed and categorized as low-medium or high. Associations between enzyme expression and response to glucocorticoid were analyzed. Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive performance of 11  -HSD1 expression.

Among the 25 treated patients with glucocorticoid therapy, 21 (84.0%) demonstrated clinical improvement, while 4 (16.0%) showed no clinical response. Baseline diagnostic subtypes and MHC class I expression were not significantly associated with treatment outcome (p = 0.37 and p = 0.59, respectively). In contrast, high 11  -HSD1 expression was significantly associated with clinical improvement (66.7% vs. 0% in non-responders; p = 0.026). High 11  -HSD1 expression was associated with increased odds of response (OR = 17.4, 95% CI: 0.77-392). ROC analysis demonstrated good predictive performance (AUC = 0.83).

Elevated muscle 11  -HSD1 expression before glucocorticoid therapy was associated with an improved clinical response after therapy in IMs. These findings support the potential role of 11  -HSD1 as a predictive biomarker.