Diverse molecular signatures observed in patients with cutaneous lupus erythematosus

Linked Article: Zhu et al . Br J Dermatol 2021; 185:563–572. Cutaneous lupus erythematosus (CLE) is an autoimmune connective tissue disease affecting the skin. It has been estimated there are approximately 4·0 patients with the condition per 100,000 people. It affects more women than men and more African Americans than other ethnicities. CLE is a clinically diverse disease and can be divided into several subtypes including subacute CLE, discoid lupus erythematosus and lupus erythematosus tumidus. Although CLE can have different clinical presentations, patients largely receive the same initial treatments. This study was conducted in Dallas, Texas, USA and aimed to assess the molecular diversity found in patients with CLE. Blood samples were collected from a racially and ethnically diverse group of patients with CLE ( n = 62) and gene expression was then studied using RNA sequencing. Analysis of data revealed that there were six unique subsets or groups of patients with CLE. The demographics and clinical features of these subsets were compared. It was found that two mostly non‐African American and subacute CLE groups had inflammation and neutrophil signatures. Three clusters of predominantly African American patients and patients with discoid lupus erythematosus had increased expression of genes that related to T cells. This study shows that the molecular diversity of patients with CLE may reveal greater variation in CLE than previously recognized from just the clinical presentation of the disease. Future studies to better understand this molecular diversity in CLE can aid in the development of more targeted treatments for these different subsets of patients with CLE.