The clinical phenotype of dermatomyositis (DM) is uniquely influenced by specific autoantibodies. DM patients with anti-TIF1γ autoantibodies are at an increased risk of cancer. Using the PhiP-Seq (Phage Immuno-Precipitation Sequencing) technique, this study showed that anti-TIF1γ-positive DM patients with co-existing anti-Sp4 autoantibodies had significantly fewer malignancies or showed effective tumor eradication. Therefore, anti-Sp4 autoantibody could be used as biomarker in identifying anti-TIF1γ-positive DM patients who do not require aggressive cancer screening.
What is exciting about this article?
Dermatomyositis (DM) is a debilitating autoimmune muscle disease causing muscle weakness and skin rash. Approximately 70% of people with DM have a myositis-specific autoantibody that is associated with a distinct clinical phenotype. This study found that the presence of novel anti-Sp4 autoantibodies among DM patients who are positive for anti-TIF1γ autoantibodies appeared to mitigate cancer risk. This report warrants future research to determine specific biomarkers that reduce cancer risk in DM patients.
How does this fit into the larger NIAMS portfolio?
Dr. Mammen’s research focuses on human muscle disease as well as the basic biology of skeletal muscle regeneration. This study is an example of a productive collaboration between the Mammen lab and the Johns Hopkins Myositis Center that specializes in treating this rare family of autoimmune diseases affecting healthy muscles of the body. In the future, identifying new biomarkers to screen patients with DM for other associated clinical phenotypes will help manage this autoimmune disease better.
Research reported in this publication was supported by the Intramural Research Program of the NIHʼs National Institute of Arthritis and Musculoskeletal and Skin Diseases.